xref: /freebsd-10.1-release/sys/dev/ath/if_ath.c

/*-
 * Copyright (c) 2002-2009 Sam Leffler, Errno Consulting
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer,
 *    without modification.
 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 *    similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any
 *    redistribution must be conditioned upon including a substantially
 *    similar Disclaimer requirement for further binary redistribution.
 *
 * NO WARRANTY
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY
 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
 * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY,
 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGES.
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD: head/sys/dev/ath/if_ath.c 190571 2009-03-30 19:23:49Z sam $");

/*
 * Driver for the Atheros Wireless LAN controller.
 *
 * This software is derived from work of Atsushi Onoe; his contribution
 * is greatly appreciated.
 */

#include "opt_inet.h"
#include "opt_ath.h"
#include "opt_wlan.h"

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/sysctl.h>
#include <sys/mbuf.h>
#include <sys/malloc.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/kernel.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/errno.h>
#include <sys/callout.h>
#include <sys/bus.h>
#include <sys/endian.h>
#include <sys/kthread.h>
#include <sys/taskqueue.h>
#include <sys/priv.h>

#include <machine/bus.h>

#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_media.h>
#include <net/if_types.h>
#include <net/if_arp.h>
#include <net/ethernet.h>
#include <net/if_llc.h>

#include <net80211/ieee80211_var.h>
#include <net80211/ieee80211_regdomain.h>
#ifdef IEEE80211_SUPPORT_TDMA
#include <net80211/ieee80211_tdma.h>
#endif

#include <net/bpf.h>

#ifdef INET
#include <netinet/in.h>
#include <netinet/if_ether.h>
#endif

#include <dev/ath/if_athvar.h>
#include <dev/ath/ath_hal/ah_devid.h>		/* XXX for softled */

#ifdef ATH_TX99_DIAG
#include <dev/ath/ath_tx99/ath_tx99.h>
#endif

/*
 * ATH_BCBUF determines the number of vap's that can transmit
 * beacons and also (currently) the number of vap's that can
 * have unique mac addresses/bssid.  When staggering beacons
 * 4 is probably a good max as otherwise the beacons become
 * very closely spaced and there is limited time for cab q traffic
 * to go out.  You can burst beacons instead but that is not good
 * for stations in power save and at some point you really want
 * another radio (and channel).
 *
 * The limit on the number of mac addresses is tied to our use of
 * the U/L bit and tracking addresses in a byte; it would be
 * worthwhile to allow more for applications like proxy sta.
 */
CTASSERT(ATH_BCBUF <= 8);

/* unaligned little endian access */
#define LE_READ_2(p)							\
	((u_int16_t)							\
	 ((((u_int8_t *)(p))[0]      ) | (((u_int8_t *)(p))[1] <<  8)))
#define LE_READ_4(p)							\
	((u_int32_t)							\
	 ((((u_int8_t *)(p))[0]      ) | (((u_int8_t *)(p))[1] <<  8) |	\
	  (((u_int8_t *)(p))[2] << 16) | (((u_int8_t *)(p))[3] << 24)))

static struct ieee80211vap *ath_vap_create(struct ieee80211com *,
		    const char name[IFNAMSIZ], int unit, int opmode,
		    int flags, const uint8_t bssid[IEEE80211_ADDR_LEN],
		    const uint8_t mac[IEEE80211_ADDR_LEN]);
static void	ath_vap_delete(struct ieee80211vap *);
static void	ath_init(void *);
static void	ath_stop_locked(struct ifnet *);
static void	ath_stop(struct ifnet *);
static void	ath_start(struct ifnet *);
static int	ath_reset(struct ifnet *);
static int	ath_reset_vap(struct ieee80211vap *, u_long);
static int	ath_media_change(struct ifnet *);
static void	ath_watchdog(void *);
static int	ath_ioctl(struct ifnet *, u_long, caddr_t);
static void	ath_fatal_proc(void *, int);
static void	ath_bmiss_vap(struct ieee80211vap *);
static void	ath_bmiss_proc(void *, int);
static int	ath_keyset(struct ath_softc *, const struct ieee80211_key *,
			struct ieee80211_node *);
static int	ath_key_alloc(struct ieee80211vap *,
			struct ieee80211_key *,
			ieee80211_keyix *, ieee80211_keyix *);
static int	ath_key_delete(struct ieee80211vap *,
			const struct ieee80211_key *);
static int	ath_key_set(struct ieee80211vap *, const struct ieee80211_key *,
			const u_int8_t mac[IEEE80211_ADDR_LEN]);
static void	ath_key_update_begin(struct ieee80211vap *);
static void	ath_key_update_end(struct ieee80211vap *);
static void	ath_update_mcast(struct ifnet *);
static void	ath_update_promisc(struct ifnet *);
static void	ath_mode_init(struct ath_softc *);
static void	ath_setslottime(struct ath_softc *);
static void	ath_updateslot(struct ifnet *);
static int	ath_beaconq_setup(struct ath_hal *);
static int	ath_beacon_alloc(struct ath_softc *, struct ieee80211_node *);
static void	ath_beacon_update(struct ieee80211vap *, int item);
static void	ath_beacon_setup(struct ath_softc *, struct ath_buf *);
static void	ath_beacon_proc(void *, int);
static struct ath_buf *ath_beacon_generate(struct ath_softc *,
			struct ieee80211vap *);
static void	ath_bstuck_proc(void *, int);
static void	ath_beacon_return(struct ath_softc *, struct ath_buf *);
static void	ath_beacon_free(struct ath_softc *);
static void	ath_beacon_config(struct ath_softc *, struct ieee80211vap *);
static void	ath_descdma_cleanup(struct ath_softc *sc,
			struct ath_descdma *, ath_bufhead *);
static int	ath_desc_alloc(struct ath_softc *);
static void	ath_desc_free(struct ath_softc *);
static struct ieee80211_node *ath_node_alloc(struct ieee80211vap *,
			const uint8_t [IEEE80211_ADDR_LEN]);
static void	ath_node_free(struct ieee80211_node *);
static void	ath_node_getsignal(const struct ieee80211_node *,
			int8_t *, int8_t *);
static int	ath_rxbuf_init(struct ath_softc *, struct ath_buf *);
static void	ath_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m,
			int subtype, int rssi, int noise, u_int32_t rstamp);
static void	ath_setdefantenna(struct ath_softc *, u_int);
static void	ath_rx_proc(void *, int);
static void	ath_txq_init(struct ath_softc *sc, struct ath_txq *, int);
static struct ath_txq *ath_txq_setup(struct ath_softc*, int qtype, int subtype);
static int	ath_tx_setup(struct ath_softc *, int, int);
static int	ath_wme_update(struct ieee80211com *);
static void	ath_tx_cleanupq(struct ath_softc *, struct ath_txq *);
static void	ath_tx_cleanup(struct ath_softc *);
static void	ath_freetx(struct mbuf *);
static int	ath_tx_start(struct ath_softc *, struct ieee80211_node *,
			     struct ath_buf *, struct mbuf *);
static void	ath_tx_proc_q0(void *, int);
static void	ath_tx_proc_q0123(void *, int);
static void	ath_tx_proc(void *, int);
static void	ath_tx_draintxq(struct ath_softc *, struct ath_txq *);
static int	ath_chan_set(struct ath_softc *, struct ieee80211_channel *);
static void	ath_draintxq(struct ath_softc *);
static void	ath_stoprecv(struct ath_softc *);
static int	ath_startrecv(struct ath_softc *);
static void	ath_chan_change(struct ath_softc *, struct ieee80211_channel *);
static void	ath_scan_start(struct ieee80211com *);
static void	ath_scan_end(struct ieee80211com *);
static void	ath_set_channel(struct ieee80211com *);
static void	ath_calibrate(void *);
static int	ath_newstate(struct ieee80211vap *, enum ieee80211_state, int);
static void	ath_setup_stationkey(struct ieee80211_node *);
static void	ath_newassoc(struct ieee80211_node *, int);
static int	ath_setregdomain(struct ieee80211com *,
		    struct ieee80211_regdomain *, int,
		    struct ieee80211_channel []);
static void	ath_getradiocaps(struct ieee80211com *, int, int *,
		    struct ieee80211_channel []);
static int	ath_getchannels(struct ath_softc *);
static void	ath_led_event(struct ath_softc *, int);

static int	ath_rate_setup(struct ath_softc *, u_int mode);
static void	ath_setcurmode(struct ath_softc *, enum ieee80211_phymode);

static void	ath_sysctlattach(struct ath_softc *);
static int	ath_raw_xmit(struct ieee80211_node *,
			struct mbuf *, const struct ieee80211_bpf_params *);
static void	ath_bpfattach(struct ath_softc *);
static void	ath_announce(struct ath_softc *);

#ifdef IEEE80211_SUPPORT_TDMA
static void	ath_tdma_settimers(struct ath_softc *sc, u_int32_t nexttbtt,
		    u_int32_t bintval);
static void	ath_tdma_bintvalsetup(struct ath_softc *sc,
		    const struct ieee80211_tdma_state *tdma);
static void	ath_tdma_config(struct ath_softc *sc, struct ieee80211vap *vap);
static void	ath_tdma_update(struct ieee80211_node *ni,
		    const struct ieee80211_tdma_param *tdma, int);
static void	ath_tdma_beacon_send(struct ath_softc *sc,
		    struct ieee80211vap *vap);

static __inline void
ath_hal_setcca(struct ath_hal *ah, int ena)
{
	/*
	 * NB: fill me in; this is not provided by default because disabling
	 *     CCA in most locales violates regulatory.
	 */
}

static __inline int
ath_hal_getcca(struct ath_hal *ah)
{
	u_int32_t diag;
	if (ath_hal_getcapability(ah, HAL_CAP_DIAG, 0, &diag) != HAL_OK)
		return 1;
	return ((diag & 0x500000) == 0);
}

#define	TDMA_EP_MULTIPLIER	(1<<10) /* pow2 to optimize out * and / */
#define	TDMA_LPF_LEN		6
#define	TDMA_DUMMY_MARKER	0x127
#define	TDMA_EP_MUL(x, mul)	((x) * (mul))
#define	TDMA_IN(x)		(TDMA_EP_MUL((x), TDMA_EP_MULTIPLIER))
#define	TDMA_LPF(x, y, len) \
    ((x != TDMA_DUMMY_MARKER) ? (((x) * ((len)-1) + (y)) / (len)) : (y))
#define	TDMA_SAMPLE(x, y) do {					\
	x = TDMA_LPF((x), TDMA_IN(y), TDMA_LPF_LEN);		\
} while (0)
#define	TDMA_EP_RND(x,mul) \
	((((x)%(mul)) >= ((mul)/2)) ? ((x) + ((mul) - 1)) / (mul) : (x)/(mul))
#define	TDMA_AVG(x)		TDMA_EP_RND(x, TDMA_EP_MULTIPLIER)
#endif /* IEEE80211_SUPPORT_TDMA */

SYSCTL_DECL(_hw_ath);

/* XXX validate sysctl values */
static	int ath_longcalinterval = 30;		/* long cals every 30 secs */
SYSCTL_INT(_hw_ath, OID_AUTO, longcal, CTLFLAG_RW, &ath_longcalinterval,
	    0, "long chip calibration interval (secs)");
static	int ath_shortcalinterval = 100;		/* short cals every 100 ms */
SYSCTL_INT(_hw_ath, OID_AUTO, shortcal, CTLFLAG_RW, &ath_shortcalinterval,
	    0, "short chip calibration interval (msecs)");
static	int ath_resetcalinterval = 20*60;	/* reset cal state 20 mins */
SYSCTL_INT(_hw_ath, OID_AUTO, resetcal, CTLFLAG_RW, &ath_resetcalinterval,
	    0, "reset chip calibration results (secs)");

static	int ath_rxbuf = ATH_RXBUF;		/* # rx buffers to allocate */
SYSCTL_INT(_hw_ath, OID_AUTO, rxbuf, CTLFLAG_RW, &ath_rxbuf,
	    0, "rx buffers allocated");
TUNABLE_INT("hw.ath.rxbuf", &ath_rxbuf);
static	int ath_txbuf = ATH_TXBUF;		/* # tx buffers to allocate */
SYSCTL_INT(_hw_ath, OID_AUTO, txbuf, CTLFLAG_RW, &ath_txbuf,
	    0, "tx buffers allocated");
TUNABLE_INT("hw.ath.txbuf", &ath_txbuf);

static	int ath_bstuck_threshold = 4;		/* max missed beacons */
SYSCTL_INT(_hw_ath, OID_AUTO, bstuck, CTLFLAG_RW, &ath_bstuck_threshold,
	    0, "max missed beacon xmits before chip reset");

#ifdef ATH_DEBUG
enum {
	ATH_DEBUG_XMIT		= 0x00000001,	/* basic xmit operation */
	ATH_DEBUG_XMIT_DESC	= 0x00000002,	/* xmit descriptors */
	ATH_DEBUG_RECV		= 0x00000004,	/* basic recv operation */
	ATH_DEBUG_RECV_DESC	= 0x00000008,	/* recv descriptors */
	ATH_DEBUG_RATE		= 0x00000010,	/* rate control */
	ATH_DEBUG_RESET		= 0x00000020,	/* reset processing */
	ATH_DEBUG_MODE		= 0x00000040,	/* mode init/setup */
	ATH_DEBUG_BEACON 	= 0x00000080,	/* beacon handling */
	ATH_DEBUG_WATCHDOG 	= 0x00000100,	/* watchdog timeout */
	ATH_DEBUG_INTR		= 0x00001000,	/* ISR */
	ATH_DEBUG_TX_PROC	= 0x00002000,	/* tx ISR proc */
	ATH_DEBUG_RX_PROC	= 0x00004000,	/* rx ISR proc */
	ATH_DEBUG_BEACON_PROC	= 0x00008000,	/* beacon ISR proc */
	ATH_DEBUG_CALIBRATE	= 0x00010000,	/* periodic calibration */
	ATH_DEBUG_KEYCACHE	= 0x00020000,	/* key cache management */
	ATH_DEBUG_STATE		= 0x00040000,	/* 802.11 state transitions */
	ATH_DEBUG_NODE		= 0x00080000,	/* node management */
	ATH_DEBUG_LED		= 0x00100000,	/* led management */
	ATH_DEBUG_FF		= 0x00200000,	/* fast frames */
	ATH_DEBUG_DFS		= 0x00400000,	/* DFS processing */
	ATH_DEBUG_TDMA		= 0x00800000,	/* TDMA processing */
	ATH_DEBUG_TDMA_TIMER	= 0x01000000,	/* TDMA timer processing */
	ATH_DEBUG_REGDOMAIN	= 0x02000000,	/* regulatory processing */
	ATH_DEBUG_FATAL		= 0x80000000,	/* fatal errors */
	ATH_DEBUG_ANY		= 0xffffffff
};
static	int ath_debug = 0;
SYSCTL_INT(_hw_ath, OID_AUTO, debug, CTLFLAG_RW, &ath_debug,
	    0, "control debugging printfs");
TUNABLE_INT("hw.ath.debug", &ath_debug);

#define	IFF_DUMPPKTS(sc, m) \
	((sc->sc_debug & (m)) || \
	    (sc->sc_ifp->if_flags & (IFF_DEBUG|IFF_LINK2)) == (IFF_DEBUG|IFF_LINK2))
#define	DPRINTF(sc, m, fmt, ...) do {				\
	if (sc->sc_debug & (m))					\
		printf(fmt, __VA_ARGS__);			\
} while (0)
#define	KEYPRINTF(sc, ix, hk, mac) do {				\
	if (sc->sc_debug & ATH_DEBUG_KEYCACHE)			\
		ath_keyprint(sc, __func__, ix, hk, mac);	\
} while (0)
static	void ath_printrxbuf(struct ath_softc *, const struct ath_buf *bf,
	u_int ix, int);
static	void ath_printtxbuf(struct ath_softc *, const struct ath_buf *bf,
	u_int qnum, u_int ix, int done);
#else
#define	IFF_DUMPPKTS(sc, m) \
	((sc->sc_ifp->if_flags & (IFF_DEBUG|IFF_LINK2)) == (IFF_DEBUG|IFF_LINK2))
#define	DPRINTF(sc, m, fmt, ...) do {				\
	(void) sc;						\
} while (0)
#define	KEYPRINTF(sc, k, ix, mac) do {				\
	(void) sc;						\
} while (0)
#endif

MALLOC_DEFINE(M_ATHDEV, "athdev", "ath driver dma buffers");

int
ath_attach(u_int16_t devid, struct ath_softc *sc)
{
	struct ifnet *ifp;
	struct ieee80211com *ic;
	struct ath_hal *ah = NULL;
	HAL_STATUS status;
	int error = 0, i;
	u_int wmodes;
	uint8_t macaddr[IEEE80211_ADDR_LEN];

	DPRINTF(sc, ATH_DEBUG_ANY, "%s: devid 0x%x\n", __func__, devid);

	ifp = sc->sc_ifp = if_alloc(IFT_IEEE80211);
	if (ifp == NULL) {
		device_printf(sc->sc_dev, "can not if_alloc()\n");
		error = ENOSPC;
		goto bad;
	}
	ic = ifp->if_l2com;

	/* set these up early for if_printf use */
	if_initname(ifp, device_get_name(sc->sc_dev),
		device_get_unit(sc->sc_dev));

	ah = ath_hal_attach(devid, sc, sc->sc_st, sc->sc_sh, &status);
	if (ah == NULL) {
		if_printf(ifp, "unable to attach hardware; HAL status %u\n",
			status);
		error = ENXIO;
		goto bad;
	}
	sc->sc_ah = ah;
	sc->sc_invalid = 0;	/* ready to go, enable interrupt handling */
#ifdef	ATH_DEBUG
	sc->sc_debug = ath_debug;
#endif

	/*
	 * Check if the MAC has multi-rate retry support.
	 * We do this by trying to setup a fake extended
	 * descriptor.  MAC's that don't have support will
	 * return false w/o doing anything.  MAC's that do
	 * support it will return true w/o doing anything.
	 */
	sc->sc_mrretry = ath_hal_setupxtxdesc(ah, NULL, 0,0, 0,0, 0,0);

	/*
	 * Check if the device has hardware counters for PHY
	 * errors.  If so we need to enable the MIB interrupt
	 * so we can act on stat triggers.
	 */
	if (ath_hal_hwphycounters(ah))
		sc->sc_needmib = 1;

	/*
	 * Get the hardware key cache size.
	 */
	sc->sc_keymax = ath_hal_keycachesize(ah);
	if (sc->sc_keymax > ATH_KEYMAX) {
		if_printf(ifp, "Warning, using only %u of %u key cache slots\n",
			ATH_KEYMAX, sc->sc_keymax);
		sc->sc_keymax = ATH_KEYMAX;
	}
	/*
	 * Reset the key cache since some parts do not
	 * reset the contents on initial power up.
	 */
	for (i = 0; i < sc->sc_keymax; i++)
		ath_hal_keyreset(ah, i);

	/*
	 * Collect the default channel list.
	 */
	error = ath_getchannels(sc);
	if (error != 0)
		goto bad;

	/*
	 * Setup rate tables for all potential media types.
	 */
	ath_rate_setup(sc, IEEE80211_MODE_11A);
	ath_rate_setup(sc, IEEE80211_MODE_11B);
	ath_rate_setup(sc, IEEE80211_MODE_11G);
	ath_rate_setup(sc, IEEE80211_MODE_TURBO_A);
	ath_rate_setup(sc, IEEE80211_MODE_TURBO_G);
	ath_rate_setup(sc, IEEE80211_MODE_STURBO_A);
	ath_rate_setup(sc, IEEE80211_MODE_11NA);
	ath_rate_setup(sc, IEEE80211_MODE_11NG);
	ath_rate_setup(sc, IEEE80211_MODE_HALF);
	ath_rate_setup(sc, IEEE80211_MODE_QUARTER);

	/* NB: setup here so ath_rate_update is happy */
	ath_setcurmode(sc, IEEE80211_MODE_11A);

	/*
	 * Allocate tx+rx descriptors and populate the lists.
	 */
	error = ath_desc_alloc(sc);
	if (error != 0) {
		if_printf(ifp, "failed to allocate descriptors: %d\n", error);
		goto bad;
	}
	callout_init_mtx(&sc->sc_cal_ch, &sc->sc_mtx, 0);
	callout_init_mtx(&sc->sc_wd_ch, &sc->sc_mtx, 0);

	ATH_TXBUF_LOCK_INIT(sc);

	sc->sc_tq = taskqueue_create("ath_taskq", M_NOWAIT,
		taskqueue_thread_enqueue, &sc->sc_tq);
	taskqueue_start_threads(&sc->sc_tq, 1, PI_NET,
		"%s taskq", ifp->if_xname);

	TASK_INIT(&sc->sc_rxtask, 0, ath_rx_proc, sc);
	TASK_INIT(&sc->sc_bmisstask, 0, ath_bmiss_proc, sc);
	TASK_INIT(&sc->sc_bstucktask,0, ath_bstuck_proc, sc);

	/*
	 * Allocate hardware transmit queues: one queue for
	 * beacon frames and one data queue for each QoS
	 * priority.  Note that the hal handles reseting
	 * these queues at the needed time.
	 *
	 * XXX PS-Poll
	 */
	sc->sc_bhalq = ath_beaconq_setup(ah);
	if (sc->sc_bhalq == (u_int) -1) {
		if_printf(ifp, "unable to setup a beacon xmit queue!\n");
		error = EIO;
		goto bad2;
	}
	sc->sc_cabq = ath_txq_setup(sc, HAL_TX_QUEUE_CAB, 0);
	if (sc->sc_cabq == NULL) {
		if_printf(ifp, "unable to setup CAB xmit queue!\n");
		error = EIO;
		goto bad2;
	}
	/* NB: insure BK queue is the lowest priority h/w queue */
	if (!ath_tx_setup(sc, WME_AC_BK, HAL_WME_AC_BK)) {
		if_printf(ifp, "unable to setup xmit queue for %s traffic!\n",
			ieee80211_wme_acnames[WME_AC_BK]);
		error = EIO;
		goto bad2;
	}
	if (!ath_tx_setup(sc, WME_AC_BE, HAL_WME_AC_BE) ||
	    !ath_tx_setup(sc, WME_AC_VI, HAL_WME_AC_VI) ||
	    !ath_tx_setup(sc, WME_AC_VO, HAL_WME_AC_VO)) {
		/*
		 * Not enough hardware tx queues to properly do WME;
		 * just punt and assign them all to the same h/w queue.
		 * We could do a better job of this if, for example,
		 * we allocate queues when we switch from station to
		 * AP mode.
		 */
		if (sc->sc_ac2q[WME_AC_VI] != NULL)
			ath_tx_cleanupq(sc, sc->sc_ac2q[WME_AC_VI]);
		if (sc->sc_ac2q[WME_AC_BE] != NULL)
			ath_tx_cleanupq(sc, sc->sc_ac2q[WME_AC_BE]);
		sc->sc_ac2q[WME_AC_BE] = sc->sc_ac2q[WME_AC_BK];
		sc->sc_ac2q[WME_AC_VI] = sc->sc_ac2q[WME_AC_BK];
		sc->sc_ac2q[WME_AC_VO] = sc->sc_ac2q[WME_AC_BK];
	}

	/*
	 * Special case certain configurations.  Note the
	 * CAB queue is handled by these specially so don't
	 * include them when checking the txq setup mask.
	 */
	switch (sc->sc_txqsetup &~ (1<<sc->sc_cabq->axq_qnum)) {
	case 0x01:
		TASK_INIT(&sc->sc_txtask, 0, ath_tx_proc_q0, sc);
		break;
	case 0x0f:
		TASK_INIT(&sc->sc_txtask, 0, ath_tx_proc_q0123, sc);
		break;
	default:
		TASK_INIT(&sc->sc_txtask, 0, ath_tx_proc, sc);
		break;
	}

	/*
	 * Setup rate control.  Some rate control modules
	 * call back to change the anntena state so expose
	 * the necessary entry points.
	 * XXX maybe belongs in struct ath_ratectrl?
	 */
	sc->sc_setdefantenna = ath_setdefantenna;
	sc->sc_rc = ath_rate_attach(sc);
	if (sc->sc_rc == NULL) {
		error = EIO;
		goto bad2;
	}

	sc->sc_blinking = 0;
	sc->sc_ledstate = 1;
	sc->sc_ledon = 0;			/* low true */
	sc->sc_ledidle = (2700*hz)/1000;	/* 2.7sec */
	callout_init(&sc->sc_ledtimer, CALLOUT_MPSAFE);
	/*
	 * Auto-enable soft led processing for IBM cards and for
	 * 5211 minipci cards.  Users can also manually enable/disable
	 * support with a sysctl.
	 */
	sc->sc_softled = (devid == AR5212_DEVID_IBM || devid == AR5211_DEVID);
	if (sc->sc_softled) {
		ath_hal_gpioCfgOutput(ah, sc->sc_ledpin,
		    HAL_GPIO_MUX_MAC_NETWORK_LED);
		ath_hal_gpioset(ah, sc->sc_ledpin, !sc->sc_ledon);
	}

	ifp->if_softc = sc;
	ifp->if_flags = IFF_SIMPLEX | IFF_BROADCAST | IFF_MULTICAST;
	ifp->if_start = ath_start;
	ifp->if_watchdog = NULL;
	ifp->if_ioctl = ath_ioctl;
	ifp->if_init = ath_init;
	IFQ_SET_MAXLEN(&ifp->if_snd, IFQ_MAXLEN);
	ifp->if_snd.ifq_drv_maxlen = IFQ_MAXLEN;
	IFQ_SET_READY(&ifp->if_snd);

	ic->ic_ifp = ifp;
	/* XXX not right but it's not used anywhere important */
	ic->ic_phytype = IEEE80211_T_OFDM;
	ic->ic_opmode = IEEE80211_M_STA;
	ic->ic_caps =
		  IEEE80211_C_STA		/* station mode */
		| IEEE80211_C_IBSS		/* ibss, nee adhoc, mode */
		| IEEE80211_C_HOSTAP		/* hostap mode */
		| IEEE80211_C_MONITOR		/* monitor mode */
		| IEEE80211_C_AHDEMO		/* adhoc demo mode */
		| IEEE80211_C_WDS		/* 4-address traffic works */
		| IEEE80211_C_SHPREAMBLE	/* short preamble supported */
		| IEEE80211_C_SHSLOT		/* short slot time supported */
		| IEEE80211_C_WPA		/* capable of WPA1+WPA2 */
		| IEEE80211_C_BGSCAN		/* capable of bg scanning */
		| IEEE80211_C_TXFRAG		/* handle tx frags */
		;
	/*
	 * Query the hal to figure out h/w crypto support.
	 */
	if (ath_hal_ciphersupported(ah, HAL_CIPHER_WEP))
		ic->ic_cryptocaps |= IEEE80211_CRYPTO_WEP;
	if (ath_hal_ciphersupported(ah, HAL_CIPHER_AES_OCB))
		ic->ic_cryptocaps |= IEEE80211_CRYPTO_AES_OCB;
	if (ath_hal_ciphersupported(ah, HAL_CIPHER_AES_CCM))
		ic->ic_cryptocaps |= IEEE80211_CRYPTO_AES_CCM;
	if (ath_hal_ciphersupported(ah, HAL_CIPHER_CKIP))
		ic->ic_cryptocaps |= IEEE80211_CRYPTO_CKIP;
	if (ath_hal_ciphersupported(ah, HAL_CIPHER_TKIP)) {
		ic->ic_cryptocaps |= IEEE80211_CRYPTO_TKIP;
		/*
		 * Check if h/w does the MIC and/or whether the
		 * separate key cache entries are required to
		 * handle both tx+rx MIC keys.
		 */
		if (ath_hal_ciphersupported(ah, HAL_CIPHER_MIC))
			ic->ic_cryptocaps |= IEEE80211_CRYPTO_TKIPMIC;
		/*
		 * If the h/w supports storing tx+rx MIC keys
		 * in one cache slot automatically enable use.
		 */
		if (ath_hal_hastkipsplit(ah) ||
		    !ath_hal_settkipsplit(ah, AH_FALSE))
			sc->sc_splitmic = 1;
		/*
		 * If the h/w can do TKIP MIC together with WME then
		 * we use it; otherwise we force the MIC to be done
		 * in software by the net80211 layer.
		 */
		if (ath_hal_haswmetkipmic(ah))
			sc->sc_wmetkipmic = 1;
	}
	sc->sc_hasclrkey = ath_hal_ciphersupported(ah, HAL_CIPHER_CLR);
	sc->sc_mcastkey = ath_hal_getmcastkeysearch(ah);
	/*
	 * Mark key cache slots associated with global keys
	 * as in use.  If we knew TKIP was not to be used we
	 * could leave the +32, +64, and +32+64 slots free.
	 */
	for (i = 0; i < IEEE80211_WEP_NKID; i++) {
		setbit(sc->sc_keymap, i);
		setbit(sc->sc_keymap, i+64);
		if (sc->sc_splitmic) {
			setbit(sc->sc_keymap, i+32);
			setbit(sc->sc_keymap, i+32+64);
		}
	}
	/*
	 * TPC support can be done either with a global cap or
	 * per-packet support.  The latter is not available on
	 * all parts.  We're a bit pedantic here as all parts
	 * support a global cap.
	 */
	if (ath_hal_hastpc(ah) || ath_hal_hastxpowlimit(ah))
		ic->ic_caps |= IEEE80211_C_TXPMGT;

	/*
	 * Mark WME capability only if we have sufficient
	 * hardware queues to do proper priority scheduling.
	 */
	if (sc->sc_ac2q[WME_AC_BE] != sc->sc_ac2q[WME_AC_BK])
		ic->ic_caps |= IEEE80211_C_WME;
	/*
	 * Check for misc other capabilities.
	 */
	if (ath_hal_hasbursting(ah))
		ic->ic_caps |= IEEE80211_C_BURST;
	sc->sc_hasbmask = ath_hal_hasbssidmask(ah);
	sc->sc_hastsfadd = ath_hal_hastsfadjust(ah);
	if (ath_hal_hasfastframes(ah))
		ic->ic_caps |= IEEE80211_C_FF;
	wmodes = ath_hal_getwirelessmodes(ah);
	if (wmodes & (HAL_MODE_108G|HAL_MODE_TURBO))
		ic->ic_caps |= IEEE80211_C_TURBOP;
#ifdef IEEE80211_SUPPORT_TDMA
	if (ath_hal_macversion(ah) > 0x78) {
		ic->ic_caps |= IEEE80211_C_TDMA; /* capable of TDMA */
		ic->ic_tdma_update = ath_tdma_update;
	}
#endif
	/*
	 * Indicate we need the 802.11 header padded to a
	 * 32-bit boundary for 4-address and QoS frames.
	 */
	ic->ic_flags |= IEEE80211_F_DATAPAD;

	/*
	 * Query the hal about antenna support.
	 */
	sc->sc_defant = ath_hal_getdefantenna(ah);

	/*
	 * Not all chips have the VEOL support we want to
	 * use with IBSS beacons; check here for it.
	 */
	sc->sc_hasveol = ath_hal_hasveol(ah);

	/* get mac address from hardware */
	ath_hal_getmac(ah, macaddr);
	if (sc->sc_hasbmask)
		ath_hal_getbssidmask(ah, sc->sc_hwbssidmask);

	/* NB: used to size node table key mapping array */
	ic->ic_max_keyix = sc->sc_keymax;
	/* call MI attach routine. */
	ieee80211_ifattach(ic, macaddr);
	ic->ic_setregdomain = ath_setregdomain;
	ic->ic_getradiocaps = ath_getradiocaps;
	sc->sc_opmode = HAL_M_STA;

	/* override default methods */
	ic->ic_newassoc = ath_newassoc;
	ic->ic_updateslot = ath_updateslot;
	ic->ic_wme.wme_update = ath_wme_update;
	ic->ic_vap_create = ath_vap_create;
	ic->ic_vap_delete = ath_vap_delete;
	ic->ic_raw_xmit = ath_raw_xmit;
	ic->ic_update_mcast = ath_update_mcast;
	ic->ic_update_promisc = ath_update_promisc;
	ic->ic_node_alloc = ath_node_alloc;
	sc->sc_node_free = ic->ic_node_free;
	ic->ic_node_free = ath_node_free;
	ic->ic_node_getsignal = ath_node_getsignal;
	ic->ic_scan_start = ath_scan_start;
	ic->ic_scan_end = ath_scan_end;
	ic->ic_set_channel = ath_set_channel;

	ath_bpfattach(sc);
	/*
	 * Setup dynamic sysctl's now that country code and
	 * regdomain are available from the hal.
	 */
	ath_sysctlattach(sc);

	if (bootverbose)
		ieee80211_announce(ic);
	ath_announce(sc);
	return 0;
bad2:
	ath_tx_cleanup(sc);
	ath_desc_free(sc);
bad:
	if (ah)
		ath_hal_detach(ah);
	if (ifp != NULL)
		if_free(ifp);
	sc->sc_invalid = 1;
	return error;
}

int
ath_detach(struct ath_softc *sc)
{
	struct ifnet *ifp = sc->sc_ifp;

	DPRINTF(sc, ATH_DEBUG_ANY, "%s: if_flags %x\n",
		__func__, ifp->if_flags);

	/*
	 * NB: the order of these is important:
	 * o stop the chip so no more interrupts will fire
	 * o call the 802.11 layer before detaching the hal to
	 *   insure callbacks into the driver to delete global
	 *   key cache entries can be handled
	 * o free the taskqueue which drains any pending tasks
	 * o reclaim the bpf tap now that we know nothing will use
	 *   it (e.g. rx processing from the task q thread)
	 * o reclaim the tx queue data structures after calling
	 *   the 802.11 layer as we'll get called back to reclaim
	 *   node state and potentially want to use them
	 * o to cleanup the tx queues the hal is called, so detach
	 *   it last
	 * Other than that, it's straightforward...
	 */
	ath_stop(ifp);
	ieee80211_ifdetach(ifp->if_l2com);
	taskqueue_free(sc->sc_tq);
	bpfdetach(ifp);
#ifdef ATH_TX99_DIAG
	if (sc->sc_tx99 != NULL)
		sc->sc_tx99->detach(sc->sc_tx99);
#endif
	ath_rate_detach(sc->sc_rc);
	ath_desc_free(sc);
	ath_tx_cleanup(sc);
	ath_hal_detach(sc->sc_ah);	/* NB: sets chip in full sleep */
	if_free(ifp);

	return 0;
}

/*
 * MAC address handling for multiple BSS on the same radio.
 * The first vap uses the MAC address from the EEPROM.  For
 * subsequent vap's we set the U/L bit (bit 1) in the MAC
 * address and use the next six bits as an index.
 */
static void
assign_address(struct ath_softc *sc, uint8_t mac[IEEE80211_ADDR_LEN], int clone)
{
	int i;

	if (clone && sc->sc_hasbmask) {
		/* NB: we only do this if h/w supports multiple bssid */
		for (i = 0; i < 8; i++)
			if ((sc->sc_bssidmask & (1<<i)) == 0)
				break;
		if (i != 0)
			mac[0] |= (i << 2)|0x2;
	} else
		i = 0;
	sc->sc_bssidmask |= 1<<i;
	sc->sc_hwbssidmask[0] &= ~mac[0];
	if (i == 0)
		sc->sc_nbssid0++;
}

static void
reclaim_address(struct ath_softc *sc, const uint8_t mac[IEEE80211_ADDR_LEN])
{
	int i = mac[0] >> 2;
	uint8_t mask;

	if (i != 0 || --sc->sc_nbssid0 == 0) {
		sc->sc_bssidmask &= ~(1<<i);
		/* recalculate bssid mask from remaining addresses */
		mask = 0xff;
		for (i = 1; i < 8; i++)
			if (sc->sc_bssidmask & (1<<i))
				mask &= ~((i<<2)|0x2);
		sc->sc_hwbssidmask[0] |= mask;
	}
}

/*
 * Assign a beacon xmit slot.  We try to space out
 * assignments so when beacons are staggered the
 * traffic coming out of the cab q has maximal time
 * to go out before the next beacon is scheduled.
 */
static int
assign_bslot(struct ath_softc *sc)
{
	u_int slot, free;

	free = 0;
	for (slot = 0; slot < ATH_BCBUF; slot++)
		if (sc->sc_bslot[slot] == NULL) {
			if (sc->sc_bslot[(slot+1)%ATH_BCBUF] == NULL &&
			    sc->sc_bslot[(slot-1)%ATH_BCBUF] == NULL)
				return slot;
			free = slot;
			/* NB: keep looking for a double slot */
		}
	return free;
}

static struct ieee80211vap *
ath_vap_create(struct ieee80211com *ic,
	const char name[IFNAMSIZ], int unit, int opmode, int flags,
	const uint8_t bssid[IEEE80211_ADDR_LEN],
	const uint8_t mac0[IEEE80211_ADDR_LEN])
{
	struct ath_softc *sc = ic->ic_ifp->if_softc;
	struct ath_vap *avp;
	struct ieee80211vap *vap;
	uint8_t mac[IEEE80211_ADDR_LEN];
	int ic_opmode, needbeacon, error;

	avp = (struct ath_vap *) malloc(sizeof(struct ath_vap),
	    M_80211_VAP, M_WAITOK | M_ZERO);
	needbeacon = 0;
	IEEE80211_ADDR_COPY(mac, mac0);

	ATH_LOCK(sc);
	switch (opmode) {
	case IEEE80211_M_STA:
		if (sc->sc_nstavaps != 0) {	/* XXX only 1 sta for now */
			device_printf(sc->sc_dev, "only 1 sta vap supported\n");
			goto bad;
		}
		if (sc->sc_nvaps) {
			/*
			 * When there are multiple vaps we must fall
			 * back to s/w beacon miss handling.
			 */
			flags |= IEEE80211_CLONE_NOBEACONS;
		}
		if (flags & IEEE80211_CLONE_NOBEACONS)
			ic_opmode = IEEE80211_M_HOSTAP;
		else
			ic_opmode = opmode;
		break;
	case IEEE80211_M_IBSS:
		if (sc->sc_nvaps != 0) {	/* XXX only 1 for now */
			device_printf(sc->sc_dev,
			    "only 1 ibss vap supported\n");
			goto bad;
		}
		ic_opmode = opmode;
		needbeacon = 1;
		break;
	case IEEE80211_M_AHDEMO:
#ifdef IEEE80211_SUPPORT_TDMA
		if (flags & IEEE80211_CLONE_TDMA) {
			needbeacon = 1;
			flags |= IEEE80211_CLONE_NOBEACONS;
		}
		/* fall thru... */
#endif
	case IEEE80211_M_MONITOR:
		if (sc->sc_nvaps != 0 && ic->ic_opmode != opmode) {
			/* XXX not right for monitor mode */
			ic_opmode = ic->ic_opmode;
		} else
			ic_opmode = opmode;
		break;
	case IEEE80211_M_HOSTAP:
		needbeacon = 1;
		/* fall thru... */
	case IEEE80211_M_WDS:
		if (sc->sc_nvaps && ic->ic_opmode == IEEE80211_M_STA) {
			device_printf(sc->sc_dev,
			    "wds not supported in sta mode\n");
			goto bad;
		}
		if (opmode == IEEE80211_M_WDS) {
			/*
			 * Silently remove any request for a unique
			 * bssid; WDS vap's always share the local
			 * mac address.
			 */
			flags &= ~IEEE80211_CLONE_BSSID;
		}
		ic_opmode = IEEE80211_M_HOSTAP;
		break;
	default:
		device_printf(sc->sc_dev, "unknown opmode %d\n", opmode);
		goto bad;
	}
	/*
	 * Check that a beacon buffer is available; the code below assumes it.
	 */
	if (needbeacon & STAILQ_EMPTY(&sc->sc_bbuf)) {
		device_printf(sc->sc_dev, "no beacon buffer available\n");
		goto bad;
	}

	/* STA, AHDEMO? */
	if (opmode == IEEE80211_M_HOSTAP) {
		assign_address(sc, mac, flags & IEEE80211_CLONE_BSSID);
		ath_hal_setbssidmask(sc->sc_ah, sc->sc_hwbssidmask);
	}

	vap = &avp->av_vap;
	/* XXX can't hold mutex across if_alloc */
	ATH_UNLOCK(sc);
	error = ieee80211_vap_setup(ic, vap, name, unit, opmode, flags,
	    bssid, mac);
	ATH_LOCK(sc);
	if (error != 0) {
		device_printf(sc->sc_dev, "%s: error %d creating vap\n",
		    __func__, error);
		goto bad2;
	}

	/* h/w crypto support */
	vap->iv_key_alloc = ath_key_alloc;
	vap->iv_key_delete = ath_key_delete;
	vap->iv_key_set = ath_key_set;
	vap->iv_key_update_begin = ath_key_update_begin;
	vap->iv_key_update_end = ath_key_update_end;

	/* override various methods */
	avp->av_recv_mgmt = vap->iv_recv_mgmt;
	vap->iv_recv_mgmt = ath_recv_mgmt;
	vap->iv_reset = ath_reset_vap;
	vap->iv_update_beacon = ath_beacon_update;
	avp->av_newstate = vap->iv_newstate;
	vap->iv_newstate = ath_newstate;
	avp->av_bmiss = vap->iv_bmiss;
	vap->iv_bmiss = ath_bmiss_vap;

	avp->av_bslot = -1;
	if (needbeacon) {
		/*
		 * Allocate beacon state and setup the q for buffered
		 * multicast frames.  We know a beacon buffer is
		 * available because we checked above.
		 */
		avp->av_bcbuf = STAILQ_FIRST(&sc->sc_bbuf);
		STAILQ_REMOVE_HEAD(&sc->sc_bbuf, bf_list);
		if (opmode != IEEE80211_M_IBSS || !sc->sc_hasveol) {
			/*
			 * Assign the vap to a beacon xmit slot.  As above
			 * this cannot fail to find a free one.
			 */
			avp->av_bslot = assign_bslot(sc);
			KASSERT(sc->sc_bslot[avp->av_bslot] == NULL,
			    ("beacon slot %u not empty", avp->av_bslot));
			sc->sc_bslot[avp->av_bslot] = vap;
			sc->sc_nbcnvaps++;
		}
		if (sc->sc_hastsfadd && sc->sc_nbcnvaps > 0) {
			/*
			 * Multple vaps are to transmit beacons and we
			 * have h/w support for TSF adjusting; enable
			 * use of staggered beacons.
			 */
			sc->sc_stagbeacons = 1;
		}
		ath_txq_init(sc, &avp->av_mcastq, ATH_TXQ_SWQ);
	}

	ic->ic_opmode = ic_opmode;
	if (opmode != IEEE80211_M_WDS) {
		sc->sc_nvaps++;
		if (opmode == IEEE80211_M_STA)
			sc->sc_nstavaps++;
	}
	switch (ic_opmode) {
	case IEEE80211_M_IBSS:
		sc->sc_opmode = HAL_M_IBSS;
		break;
	case IEEE80211_M_STA:
		sc->sc_opmode = HAL_M_STA;
		break;
	case IEEE80211_M_AHDEMO:
#ifdef IEEE80211_SUPPORT_TDMA
		if (vap->iv_caps & IEEE80211_C_TDMA) {
			sc->sc_tdma = 1;
			/* NB: disable tsf adjust */
			sc->sc_stagbeacons = 0;
		}
		/*
		 * NB: adhoc demo mode is a pseudo mode; to the hal it's
		 * just ap mode.
		 */
		/* fall thru... */
#endif
	case IEEE80211_M_HOSTAP:
		sc->sc_opmode = HAL_M_HOSTAP;
		break;
	case IEEE80211_M_MONITOR:
		sc->sc_opmode = HAL_M_MONITOR;
		break;
	default:
		/* XXX should not happen */
		break;
	}
	if (sc->sc_hastsfadd) {
		/*
		 * Configure whether or not TSF adjust should be done.
		 */
		ath_hal_settsfadjust(sc->sc_ah, sc->sc_stagbeacons);
	}
	if (flags & IEEE80211_CLONE_NOBEACONS) {
		/*
		 * Enable s/w beacon miss handling.
		 */
		sc->sc_swbmiss = 1;
	}
	ATH_UNLOCK(sc);

	/* complete setup */
	ieee80211_vap_attach(vap, ath_media_change, ieee80211_media_status);
	return vap;
bad2:
	reclaim_address(sc, mac);
	ath_hal_setbssidmask(sc->sc_ah, sc->sc_hwbssidmask);
bad:
	free(avp, M_80211_VAP);
	ATH_UNLOCK(sc);
	return NULL;
}

static void
ath_vap_delete(struct ieee80211vap *vap)
{
	struct ieee80211com *ic = vap->iv_ic;
	struct ifnet *ifp = ic->ic_ifp;
	struct ath_softc *sc = ifp->if_softc;
	struct ath_hal *ah = sc->sc_ah;
	struct ath_vap *avp = ATH_VAP(vap);

	if (ifp->if_drv_flags & IFF_DRV_RUNNING) {
		/*
		 * Quiesce the hardware while we remove the vap.  In
		 * particular we need to reclaim all references to
		 * the vap state by any frames pending on the tx queues.
		 */
		ath_hal_intrset(ah, 0);		/* disable interrupts */
		ath_draintxq(sc);		/* stop xmit side */
		ath_stoprecv(sc);		/* stop recv side */
	}

	ieee80211_vap_detach(vap);
	ATH_LOCK(sc);
	/*
	 * Reclaim beacon state.  Note this must be done before
	 * the vap instance is reclaimed as we may have a reference
	 * to it in the buffer for the beacon frame.
	 */
	if (avp->av_bcbuf != NULL) {
		if (avp->av_bslot != -1) {
			sc->sc_bslot[avp->av_bslot] = NULL;
			sc->sc_nbcnvaps--;
		}
		ath_beacon_return(sc, avp->av_bcbuf);
		avp->av_bcbuf = NULL;
		if (sc->sc_nbcnvaps == 0) {
			sc->sc_stagbeacons = 0;
			if (sc->sc_hastsfadd)
				ath_hal_settsfadjust(sc->sc_ah, 0);
		}
		/*
		 * Reclaim any pending mcast frames for the vap.
		 */
		ath_tx_draintxq(sc, &avp->av_mcastq);
		ATH_TXQ_LOCK_DESTROY(&avp->av_mcastq);
	}
	/*
	 * Update bookkeeping.
	 */
	if (vap->iv_opmode == IEEE80211_M_STA) {
		sc->sc_nstavaps--;
		if (sc->sc_nstavaps == 0 && sc->sc_swbmiss)
			sc->sc_swbmiss = 0;
	} else if (vap->iv_opmode == IEEE80211_M_HOSTAP) {
		reclaim_address(sc, vap->iv_myaddr);
		ath_hal_setbssidmask(ah, sc->sc_hwbssidmask);
	}
	if (vap->iv_opmode != IEEE80211_M_WDS)
		sc->sc_nvaps--;
#ifdef IEEE80211_SUPPORT_TDMA
	/* TDMA operation ceases when the last vap is destroyed */
	if (sc->sc_tdma && sc->sc_nvaps == 0) {
		sc->sc_tdma = 0;
		sc->sc_swbmiss = 0;
	}
#endif
	ATH_UNLOCK(sc);
	free(avp, M_80211_VAP);

	if (ifp->if_drv_flags & IFF_DRV_RUNNING) {
		/*
		 * Restart rx+tx machines if still running (RUNNING will
		 * be reset if we just destroyed the last vap).
		 */
		if (ath_startrecv(sc) != 0)
			if_printf(ifp, "%s: unable to restart recv logic\n",
			    __func__);
		if (sc->sc_beacons)
			ath_beacon_config(sc, NULL);
		ath_hal_intrset(ah, sc->sc_imask);
	}
}

void
ath_suspend(struct ath_softc *sc)
{
	struct ifnet *ifp = sc->sc_ifp;
	struct ieee80211com *ic = ifp->if_l2com;

	DPRINTF(sc, ATH_DEBUG_ANY, "%s: if_flags %x\n",
		__func__, ifp->if_flags);

	sc->sc_resume_up = (ifp->if_flags & IFF_UP) != 0;
	if (ic->ic_opmode == IEEE80211_M_STA)
		ath_stop(ifp);
	else
		ieee80211_suspend_all(ic);
	/*
	 * NB: don't worry about putting the chip in low power
	 * mode; pci will power off our socket on suspend and
	 * cardbus detaches the device.
	 */
}

/*
 * Reset the key cache since some parts do not reset the
 * contents on resume.  First we clear all entries, then
 * re-load keys that the 802.11 layer assumes are setup
 * in h/w.
 */
static void
ath_reset_keycache(struct ath_softc *sc)
{
	struct ifnet *ifp = sc->sc_ifp;
	struct ieee80211com *ic = ifp->if_l2com;
	struct ath_hal *ah = sc->sc_ah;
	int i;

	for (i = 0; i < sc->sc_keymax; i++)
		ath_hal_keyreset(ah, i);
	ieee80211_crypto_reload_keys(ic);
}

void
ath_resume(struct ath_softc *sc)
{
	struct ifnet *ifp = sc->sc_ifp;
	struct ieee80211com *ic = ifp->if_l2com;
	struct ath_hal *ah = sc->sc_ah;
	HAL_STATUS status;

	DPRINTF(sc, ATH_DEBUG_ANY, "%s: if_flags %x\n",
		__func__, ifp->if_flags);

	/*
	 * Must reset the chip before we reload the
	 * keycache as we were powered down on suspend.
	 */
	ath_hal_reset(ah, sc->sc_opmode,
	    sc->sc_curchan != NULL ? sc->sc_curchan : ic->ic_curchan,
	    AH_FALSE, &status);
	ath_reset_keycache(sc);
	if (sc->sc_resume_up) {
		if (ic->ic_opmode == IEEE80211_M_STA) {
			ath_init(sc);
			ieee80211_beacon_miss(ic);
		} else
			ieee80211_resume_all(ic);
	}
	if (sc->sc_softled) {
		ath_hal_gpioCfgOutput(ah, sc->sc_ledpin,
		    HAL_GPIO_MUX_MAC_NETWORK_LED);
		ath_hal_gpioset(ah, sc->sc_ledpin, !sc->sc_ledon);
	}
}

void
ath_shutdown(struct ath_softc *sc)
{
	struct ifnet *ifp = sc->sc_ifp;

	DPRINTF(sc, ATH_DEBUG_ANY, "%s: if_flags %x\n",
		__func__, ifp->if_flags);

	ath_stop(ifp);
	/* NB: no point powering down chip as we're about to reboot */
}

/*
 * Interrupt handler.  Most of the actual processing is deferred.
 */
void
ath_intr(void *arg)
{
	struct ath_softc *sc = arg;
	struct ifnet *ifp = sc->sc_ifp;
	struct ath_hal *ah = sc->sc_ah;
	HAL_INT status;

	if (sc->sc_invalid) {
		/*
		 * The hardware is not ready/present, don't touch anything.
		 * Note this can happen early on if the IRQ is shared.
		 */
		DPRINTF(sc, ATH_DEBUG_ANY, "%s: invalid; ignored\n", __func__);
		return;
	}
	if (!ath_hal_intrpend(ah))		/* shared irq, not for us */
		return;
	if ((ifp->if_flags & IFF_UP) == 0 ||
	    (ifp->if_drv_flags & IFF_DRV_RUNNING) == 0) {
		HAL_INT status;

		DPRINTF(sc, ATH_DEBUG_ANY, "%s: if_flags 0x%x\n",
			__func__, ifp->if_flags);
		ath_hal_getisr(ah, &status);	/* clear ISR */
		ath_hal_intrset(ah, 0);		/* disable further intr's */
		return;
	}
	/*
	 * Figure out the reason(s) for the interrupt.  Note
	 * that the hal returns a pseudo-ISR that may include
	 * bits we haven't explicitly enabled so we mask the
	 * value to insure we only process bits we requested.
	 */
	ath_hal_getisr(ah, &status);		/* NB: clears ISR too */
	DPRINTF(sc, ATH_DEBUG_INTR, "%s: status 0x%x\n", __func__, status);
	status &= sc->sc_imask;			/* discard unasked for bits */
	if (status & HAL_INT_FATAL) {
		sc->sc_stats.ast_hardware++;
		ath_hal_intrset(ah, 0);		/* disable intr's until reset */
		ath_fatal_proc(sc, 0);
	} else {
		if (status & HAL_INT_SWBA) {
			/*
			 * Software beacon alert--time to send a beacon.
			 * Handle beacon transmission directly; deferring
			 * this is too slow to meet timing constraints
			 * under load.
			 */
#ifdef IEEE80211_SUPPORT_TDMA
			if (sc->sc_tdma) {
				if (sc->sc_tdmaswba == 0) {
					struct ieee80211com *ic = ifp->if_l2com;
					struct ieee80211vap *vap =
					    TAILQ_FIRST(&ic->ic_vaps);
					ath_tdma_beacon_send(sc, vap);
					sc->sc_tdmaswba =
					    vap->iv_tdma->tdma_bintval;
				} else
					sc->sc_tdmaswba--;
			} else
#endif
				ath_beacon_proc(sc, 0);
		}
		if (status & HAL_INT_RXEOL) {
			/*
			 * NB: the hardware should re-read the link when
			 *     RXE bit is written, but it doesn't work at
			 *     least on older hardware revs.
			 */
			sc->sc_stats.ast_rxeol++;
			sc->sc_rxlink = NULL;
		}
		if (status & HAL_INT_TXURN) {
			sc->sc_stats.ast_txurn++;
			/* bump tx trigger level */
			ath_hal_updatetxtriglevel(ah, AH_TRUE);
		}
		if (status & HAL_INT_RX)
			taskqueue_enqueue(sc->sc_tq, &sc->sc_rxtask);
		if (status & HAL_INT_TX)
			taskqueue_enqueue(sc->sc_tq, &sc->sc_txtask);
		if (status & HAL_INT_BMISS) {
			sc->sc_stats.ast_bmiss++;
			taskqueue_enqueue(sc->sc_tq, &sc->sc_bmisstask);
		}
		if (status & HAL_INT_MIB) {
			sc->sc_stats.ast_mib++;
			/*
			 * Disable interrupts until we service the MIB
			 * interrupt; otherwise it will continue to fire.
			 */
			ath_hal_intrset(ah, 0);
			/*
			 * Let the hal handle the event.  We assume it will
			 * clear whatever condition caused the interrupt.
			 */
			ath_hal_mibevent(ah, &sc->sc_halstats);
			ath_hal_intrset(ah, sc->sc_imask);
		}
		if (status & HAL_INT_RXORN) {
			/* NB: hal marks HAL_INT_FATAL when RXORN is fatal */
			sc->sc_stats.ast_rxorn++;
		}
	}
}

static void
ath_fatal_proc(void *arg, int pending)
{
	struct ath_softc *sc = arg;
	struct ifnet *ifp = sc->sc_ifp;
	u_int32_t *state;
	u_int32_t len;
	void *sp;

	if_printf(ifp, "hardware error; resetting\n");
	/*
	 * Fatal errors are unrecoverable.  Typically these
	 * are caused by DMA errors.  Collect h/w state from
	 * the hal so we can diagnose what's going on.
	 */
	if (ath_hal_getfatalstate(sc->sc_ah, &sp, &len)) {
		KASSERT(len >= 6*sizeof(u_int32_t), ("len %u bytes", len));
		state = sp;
		if_printf(ifp, "0x%08x 0x%08x 0x%08x, 0x%08x 0x%08x 0x%08x\n",
		    state[0], state[1] , state[2], state[3],
		    state[4], state[5]);
	}
	ath_reset(ifp);
}

static void
ath_bmiss_vap(struct ieee80211vap *vap)
{
	/*
	 * Workaround phantom bmiss interrupts by sanity-checking
	 * the time of our last rx'd frame.  If it is within the
	 * beacon miss interval then ignore the interrupt.  If it's
	 * truly a bmiss we'll get another interrupt soon and that'll
	 * be dispatched up for processing.  Note this applies only
	 * for h/w beacon miss events.
	 */
	if ((vap->iv_flags_ext & IEEE80211_FEXT_SWBMISS) == 0) {
		struct ifnet *ifp = vap->iv_ic->ic_ifp;
		struct ath_softc *sc = ifp->if_softc;
		u_int64_t lastrx = sc->sc_lastrx;
		u_int64_t tsf = ath_hal_gettsf64(sc->sc_ah);
		u_int bmisstimeout =
			vap->iv_bmissthreshold * vap->iv_bss->ni_intval * 1024;

		DPRINTF(sc, ATH_DEBUG_BEACON,
		    "%s: tsf %llu lastrx %lld (%llu) bmiss %u\n",
		    __func__, (unsigned long long) tsf,
		    (unsigned long long)(tsf - lastrx),
		    (unsigned long long) lastrx, bmisstimeout);

		if (tsf - lastrx <= bmisstimeout) {
			sc->sc_stats.ast_bmiss_phantom++;
			return;
		}
	}
	ATH_VAP(vap)->av_bmiss(vap);
}

static int
ath_hal_gethangstate(struct ath_hal *ah, uint32_t mask, uint32_t *hangs)
{
	uint32_t rsize;
	void *sp;

	if (!ath_hal_getdiagstate(ah, 32, &mask, sizeof(&mask), &sp, &rsize))
		return 0;
	KASSERT(rsize == sizeof(uint32_t), ("resultsize %u", rsize));
	*hangs = *(uint32_t *)sp;
	return 1;
}

static void
ath_bmiss_proc(void *arg, int pending)
{
	struct ath_softc *sc = arg;
	struct ifnet *ifp = sc->sc_ifp;
	uint32_t hangs;

	DPRINTF(sc, ATH_DEBUG_ANY, "%s: pending %u\n", __func__, pending);

	if (ath_hal_gethangstate(sc->sc_ah, 0xff, &hangs) && hangs != 0) {
		if_printf(ifp, "bb hang detected (0x%x), reseting\n", hangs);
		ath_reset(ifp);
	} else
		ieee80211_beacon_miss(ifp->if_l2com);
}

/*
 * Handle TKIP MIC setup to deal hardware that doesn't do MIC
 * calcs together with WME.  If necessary disable the crypto
 * hardware and mark the 802.11 state so keys will be setup
 * with the MIC work done in software.
 */
static void
ath_settkipmic(struct ath_softc *sc)
{
	struct ifnet *ifp = sc->sc_ifp;
	struct ieee80211com *ic = ifp->if_l2com;

	if ((ic->ic_cryptocaps & IEEE80211_CRYPTO_TKIP) && !sc->sc_wmetkipmic) {
		if (ic->ic_flags & IEEE80211_F_WME) {
			ath_hal_settkipmic(sc->sc_ah, AH_FALSE);
			ic->ic_cryptocaps &= ~IEEE80211_CRYPTO_TKIPMIC;
		} else {
			ath_hal_settkipmic(sc->sc_ah, AH_TRUE);
			ic->ic_cryptocaps |= IEEE80211_CRYPTO_TKIPMIC;
		}
	}
}

static void
ath_init(void *arg)
{
	struct ath_softc *sc = (struct ath_softc *) arg;
	struct ifnet *ifp = sc->sc_ifp;
	struct ieee80211com *ic = ifp->if_l2com;
	struct ath_hal *ah = sc->sc_ah;
	HAL_STATUS status;

	DPRINTF(sc, ATH_DEBUG_ANY, "%s: if_flags 0x%x\n",
		__func__, ifp->if_flags);

	ATH_LOCK(sc);
	/*
	 * Stop anything previously setup.  This is safe
	 * whether this is the first time through or not.
	 */
	ath_stop_locked(ifp);

	/*
	 * The basic interface to setting the hardware in a good
	 * state is ``reset''.  On return the hardware is known to
	 * be powered up and with interrupts disabled.  This must
	 * be followed by initialization of the appropriate bits
	 * and then setup of the interrupt mask.
	 */
	ath_settkipmic(sc);
	if (!ath_hal_reset(ah, sc->sc_opmode, ic->ic_curchan, AH_FALSE, &status)) {
		if_printf(ifp, "unable to reset hardware; hal status %u\n",
			status);
		ATH_UNLOCK(sc);
		return;
	}
	ath_chan_change(sc, ic->ic_curchan);

	/*
	 * Likewise this is set during reset so update
	 * state cached in the driver.
	 */
	sc->sc_diversity = ath_hal_getdiversity(ah);
	sc->sc_lastlongcal = 0;
	sc->sc_resetcal = 1;
	sc->sc_lastcalreset = 0;

	/*
	 * Setup the hardware after reset: the key cache
	 * is filled as needed and the receive engine is
	 * set going.  Frame transmit is handled entirely
	 * in the frame output path; there's nothing to do
	 * here except setup the interrupt mask.
	 */
	if (ath_startrecv(sc) != 0) {
		if_printf(ifp, "unable to start recv logic\n");
		ATH_UNLOCK(sc);
		return;
	}

	/*
	 * Enable interrupts.
	 */
	sc->sc_imask = HAL_INT_RX | HAL_INT_TX
		  | HAL_INT_RXEOL | HAL_INT_RXORN
		  | HAL_INT_FATAL | HAL_INT_GLOBAL;
	/*
	 * Enable MIB interrupts when there are hardware phy counters.
	 * Note we only do this (at the moment) for station mode.
	 */
	if (sc->sc_needmib && ic->ic_opmode == IEEE80211_M_STA)
		sc->sc_imask |= HAL_INT_MIB;

	ifp->if_drv_flags |= IFF_DRV_RUNNING;
	callout_reset(&sc->sc_wd_ch, hz, ath_watchdog, sc);
	ath_hal_intrset(ah, sc->sc_imask);

	ATH_UNLOCK(sc);

#ifdef ATH_TX99_DIAG
	if (sc->sc_tx99 != NULL)
		sc->sc_tx99->start(sc->sc_tx99);
	else
#endif
	ieee80211_start_all(ic);		/* start all vap's */
}

static void
ath_stop_locked(struct ifnet *ifp)
{
	struct ath_softc *sc = ifp->if_softc;
	struct ath_hal *ah = sc->sc_ah;

	DPRINTF(sc, ATH_DEBUG_ANY, "%s: invalid %u if_flags 0x%x\n",
		__func__, sc->sc_invalid, ifp->if_flags);

	ATH_LOCK_ASSERT(sc);
	if (ifp->if_drv_flags & IFF_DRV_RUNNING) {
		/*
		 * Shutdown the hardware and driver:
		 *    reset 802.11 state machine
		 *    turn off timers
		 *    disable interrupts
		 *    turn off the radio
		 *    clear transmit machinery
		 *    clear receive machinery
		 *    drain and release tx queues
		 *    reclaim beacon resources
		 *    power down hardware
		 *
		 * Note that some of this work is not possible if the
		 * hardware is gone (invalid).
		 */
#ifdef ATH_TX99_DIAG
		if (sc->sc_tx99 != NULL)
			sc->sc_tx99->stop(sc->sc_tx99);
#endif
		callout_stop(&sc->sc_wd_ch);
		sc->sc_wd_timer = 0;
		ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
		if (!sc->sc_invalid) {
			if (sc->sc_softled) {
				callout_stop(&sc->sc_ledtimer);
				ath_hal_gpioset(ah, sc->sc_ledpin,
					!sc->sc_ledon);
				sc->sc_blinking = 0;
			}
			ath_hal_intrset(ah, 0);
		}
		ath_draintxq(sc);
		if (!sc->sc_invalid) {
			ath_stoprecv(sc);
			ath_hal_phydisable(ah);
		} else
			sc->sc_rxlink = NULL;
		ath_beacon_free(sc);	/* XXX not needed */
	}
}

static void
ath_stop(struct ifnet *ifp)
{
	struct ath_softc *sc = ifp->if_softc;

	ATH_LOCK(sc);
	ath_stop_locked(ifp);
	ATH_UNLOCK(sc);
}

/*
 * Reset the hardware w/o losing operational state.  This is
 * basically a more efficient way of doing ath_stop, ath_init,
 * followed by state transitions to the current 802.11
 * operational state.  Used to recover from various errors and
 * to reset or reload hardware state.
 */
static int
ath_reset(struct ifnet *ifp)
{
	struct ath_softc *sc = ifp->if_softc;
	struct ieee80211com *ic = ifp->if_l2com;
	struct ath_hal *ah = sc->sc_ah;
	HAL_STATUS status;

	ath_hal_intrset(ah, 0);		/* disable interrupts */
	ath_draintxq(sc);		/* stop xmit side */
	ath_stoprecv(sc);		/* stop recv side */
	ath_settkipmic(sc);		/* configure TKIP MIC handling */
	/* NB: indicate channel change so we do a full reset */
	if (!ath_hal_reset(ah, sc->sc_opmode, ic->ic_curchan, AH_TRUE, &status))
		if_printf(ifp, "%s: unable to reset hardware; hal status %u\n",
			__func__, status);
	sc->sc_diversity = ath_hal_getdiversity(ah);
	if (ath_startrecv(sc) != 0)	/* restart recv */
		if_printf(ifp, "%s: unable to start recv logic\n", __func__);
	/*
	 * We may be doing a reset in response to an ioctl
	 * that changes the channel so update any state that
	 * might change as a result.
	 */
	ath_chan_change(sc, ic->ic_curchan);
	if (sc->sc_beacons) {
#ifdef IEEE80211_SUPPORT_TDMA
		if (sc->sc_tdma)
			ath_tdma_config(sc, NULL);
		else
#endif
			ath_beacon_config(sc, NULL);	/* restart beacons */
	}
	ath_hal_intrset(ah, sc->sc_imask);

	ath_start(ifp);			/* restart xmit */
	return 0;
}

static int
ath_reset_vap(struct ieee80211vap *vap, u_long cmd)
{
	struct ieee80211com *ic = vap->iv_ic;
	struct ifnet *ifp = ic->ic_ifp;
	struct ath_softc *sc = ifp->if_softc;
	struct ath_hal *ah = sc->sc_ah;

	switch (cmd) {
	case IEEE80211_IOC_TXPOWER:
		/*
		 * If per-packet TPC is enabled, then we have nothing
		 * to do; otherwise we need to force the global limit.
		 * All this can happen directly; no need to reset.
		 */
		if (!ath_hal_gettpc(ah))
			ath_hal_settxpowlimit(ah, ic->ic_txpowlimit);
		return 0;
	}
	return ath_reset(ifp);
}

static int
ath_ff_always(struct ath_txq *txq, struct ath_buf *bf)
{
	return 0;
}

#if 0
static int
ath_ff_ageflushtestdone(struct ath_txq *txq, struct ath_buf *bf)
{
	return (txq->axq_curage - bf->bf_age) < ATH_FF_STAGEMAX;
}
#endif

/*
 * Flush FF staging queue.
 */
static void
ath_ff_stageq_flush(struct ath_softc *sc, struct ath_txq *txq,
	int (*ath_ff_flushdonetest)(struct ath_txq *txq, struct ath_buf *bf))
{
	struct ath_buf *bf;
	struct ieee80211_node *ni;
	int pktlen, pri;

	for (;;) {
		ATH_TXQ_LOCK(txq);
		/*
		 * Go from the back (oldest) to front so we can
		 * stop early based on the age of the entry.
		 */
		bf = TAILQ_LAST(&txq->axq_stageq, axq_headtype);
		if (bf == NULL || ath_ff_flushdonetest(txq, bf)) {
			ATH_TXQ_UNLOCK(txq);
			break;
		}

		ni = bf->bf_node;
		pri = M_WME_GETAC(bf->bf_m);
		KASSERT(ATH_NODE(ni)->an_ff_buf[pri],
			("no bf on staging queue %p", bf));
		ATH_NODE(ni)->an_ff_buf[pri] = NULL;
		TAILQ_REMOVE(&txq->axq_stageq, bf, bf_stagelist);

		ATH_TXQ_UNLOCK(txq);

		DPRINTF(sc, ATH_DEBUG_FF, "%s: flush frame, age %u\n",
			__func__, bf->bf_age);

		sc->sc_stats.ast_ff_flush++;

		/* encap and xmit */
		bf->bf_m = ieee80211_encap(ni, bf->bf_m);
		if (bf->bf_m == NULL) {
			DPRINTF(sc, ATH_DEBUG_XMIT | ATH_DEBUG_FF,
				"%s: discard, encapsulation failure\n",
				__func__);
			sc->sc_stats.ast_tx_encap++;
			goto bad;
		}
		pktlen = bf->bf_m->m_pkthdr.len; /* NB: don't reference below */
		if (ath_tx_start(sc, ni, bf, bf->bf_m) == 0) {
#if 0 /*XXX*/
			ifp->if_opackets++;
#endif
			continue;
		}
	bad:
		if (ni != NULL)
			ieee80211_free_node(ni);
		bf->bf_node = NULL;
		if (bf->bf_m != NULL) {
			m_freem(bf->bf_m);
			bf->bf_m = NULL;
		}

		ATH_TXBUF_LOCK(sc);
		STAILQ_INSERT_HEAD(&sc->sc_txbuf, bf, bf_list);
		ATH_TXBUF_UNLOCK(sc);
	}
}

static __inline u_int32_t
ath_ff_approx_txtime(struct ath_softc *sc, struct ath_node *an, struct mbuf *m)
{
	struct ieee80211com *ic = sc->sc_ifp->if_l2com;
	u_int32_t framelen;
	struct ath_buf *bf;

	/*
	 * Approximate the frame length to be transmitted. A swag to add
	 * the following maximal values to the skb payload:
	 *   - 32: 802.11 encap + CRC
	 *   - 24: encryption overhead (if wep bit)
	 *   - 4 + 6: fast-frame header and padding
	 *   - 16: 2 LLC FF tunnel headers
	 *   - 14: 1 802.3 FF tunnel header (skb already accounts for 2nd)
	 */
	framelen = m->m_pkthdr.len + 32 + 4 + 6 + 16 + 14;
	if (ic->ic_flags & IEEE80211_F_PRIVACY)
		framelen += 24;
	bf = an->an_ff_buf[M_WME_GETAC(m)];
	if (bf != NULL)
		framelen += bf->bf_m->m_pkthdr.len;
	return ath_hal_computetxtime(sc->sc_ah, sc->sc_currates, framelen,
			sc->sc_lastdatarix, AH_FALSE);
}

/*
 * Determine if a data frame may be aggregated via ff tunnelling.
 * Note the caller is responsible for checking if the destination
 * supports fast frames.
 *
 *  NB: allowing EAPOL frames to be aggregated with other unicast traffic.
 *      Do 802.1x EAPOL frames proceed in the clear? Then they couldn't
 *      be aggregated with other types of frames when encryption is on?
 *
 *  NB: assumes lock on an_ff_buf effectively held by txq lock mechanism.
 */
static __inline int
ath_ff_can_aggregate(struct ath_softc *sc,
	struct ath_node *an, struct mbuf *m, int *flushq)
{
	struct ieee80211com *ic = sc->sc_ifp->if_l2com;
	struct ath_txq *txq;
	u_int32_t txoplimit;
	u_int pri;

	*flushq = 0;

	/*
	 * If there is no frame to combine with and the txq has
	 * fewer frames than the minimum required; then do not
	 * attempt to aggregate this frame.
	 */
	pri = M_WME_GETAC(m);
	txq = sc->sc_ac2q[pri];
	if (an->an_ff_buf[pri] == NULL && txq->axq_depth < sc->sc_fftxqmin)
		return 0;
	/*
	 * When not in station mode never aggregate a multicast
	 * frame; this insures, for example, that a combined frame
	 * does not require multiple encryption keys when using
	 * 802.1x/WPA.
	 */
	if (ic->ic_opmode != IEEE80211_M_STA &&
	    ETHER_IS_MULTICAST(mtod(m, struct ether_header *)->ether_dhost))
		return 0;
	/*
	 * Consult the max bursting interval to insure a combined
	 * frame fits within the TxOp window.
	 */
	txoplimit = IEEE80211_TXOP_TO_US(
		ic->ic_wme.wme_chanParams.cap_wmeParams[pri].wmep_txopLimit);
	if (txoplimit != 0 && ath_ff_approx_txtime(sc, an, m) > txoplimit) {
		DPRINTF(sc, ATH_DEBUG_XMIT | ATH_DEBUG_FF,
			"%s: FF TxOp violation\n", __func__);
		if (an->an_ff_buf[pri] != NULL)
			*flushq = 1;
		return 0;
	}
	return 1;		/* try to aggregate */
}

/*
 * Check if the supplied frame can be partnered with an existing
 * or pending frame.  Return a reference to any frame that should be
 * sent on return; otherwise return NULL.
 */
static struct mbuf *
ath_ff_check(struct ath_softc *sc, struct ath_txq *txq,
	struct ath_buf *bf, struct mbuf *m, struct ieee80211_node *ni)
{
	struct ath_node *an = ATH_NODE(ni);
	struct ath_buf *bfstaged;
	int ff_flush, pri;

	/*
	 * Check if the supplied frame can be aggregated.
	 *
	 * NB: we use the txq lock to protect references to
	 *     an->an_ff_txbuf in ath_ff_can_aggregate().
	 */
	ATH_TXQ_LOCK(txq);
	pri = M_WME_GETAC(m);
	if (ath_ff_can_aggregate(sc, an, m, &ff_flush)) {
		struct ath_buf *bfstaged = an->an_ff_buf[pri];
		if (bfstaged != NULL) {
			/*
			 * A frame is available for partnering; remove
			 * it, chain it to this one, and encapsulate.
			 */
			an->an_ff_buf[pri] = NULL;
			TAILQ_REMOVE(&txq->axq_stageq, bfstaged, bf_stagelist);
			ATH_TXQ_UNLOCK(txq);

			/*
			 * Chain mbufs and add FF magic.
			 */
			DPRINTF(sc, ATH_DEBUG_FF,
				"[%s] aggregate fast-frame, age %u\n",
				ether_sprintf(ni->ni_macaddr), txq->axq_curage);
			m->m_nextpkt = NULL;
			bfstaged->bf_m->m_nextpkt = m;
			m = bfstaged->bf_m;
			bfstaged->bf_m = NULL;
			m->m_flags |= M_FF;
			/*
			 * Release the node reference held while
			 * the packet sat on an_ff_buf[]
			 */
			bfstaged->bf_node = NULL;
			ieee80211_free_node(ni);

			/*
			 * Return bfstaged to the free list.
			 */
			ATH_TXBUF_LOCK(sc);
			STAILQ_INSERT_HEAD(&sc->sc_txbuf, bfstaged, bf_list);
			ATH_TXBUF_UNLOCK(sc);

			return m;		/* ready to go */
		} else {
			/*
			 * No frame available, queue this frame to wait
			 * for a partner.  Note that we hold the buffer
			 * and a reference to the node; we need the
			 * buffer in particular so we're certain we
			 * can flush the frame at a later time.
			 */
			DPRINTF(sc, ATH_DEBUG_FF,
				"[%s] stage fast-frame, age %u\n",
				ether_sprintf(ni->ni_macaddr), txq->axq_curage);

			bf->bf_m = m;
			bf->bf_node = ni;	/* NB: held reference */
			bf->bf_age = txq->axq_curage;
			an->an_ff_buf[pri] = bf;
			TAILQ_INSERT_HEAD(&txq->axq_stageq, bf, bf_stagelist);
			ATH_TXQ_UNLOCK(txq);

			return NULL;		/* consumed */
		}
	}
	/*
	 * Frame could not be aggregated, it needs to be returned
	 * to the caller for immediate transmission.  In addition
	 * we check if we should first flush a frame from the
	 * staging queue before sending this one.
	 *
	 * NB: ath_ff_can_aggregate only marks ff_flush if a frame
	 *     is present to flush.
	 */
	if (ff_flush) {
		int pktlen;

		bfstaged = an->an_ff_buf[pri];
		an->an_ff_buf[pri] = NULL;
		TAILQ_REMOVE(&txq->axq_stageq, bfstaged, bf_stagelist);
		ATH_TXQ_UNLOCK(txq);

		DPRINTF(sc, ATH_DEBUG_FF, "[%s] flush staged frame\n",
			ether_sprintf(an->an_node.ni_macaddr));

		/* encap and xmit */
		bfstaged->bf_m = ieee80211_encap(ni, bfstaged->bf_m);
		if (bfstaged->bf_m == NULL) {
			DPRINTF(sc, ATH_DEBUG_XMIT | ATH_DEBUG_FF,
				"%s: discard, encap failure\n", __func__);
			sc->sc_stats.ast_tx_encap++;
			goto ff_flushbad;
		}
		pktlen = bfstaged->bf_m->m_pkthdr.len;
		if (ath_tx_start(sc, ni, bfstaged, bfstaged->bf_m)) {
			DPRINTF(sc, ATH_DEBUG_XMIT,
				"%s: discard, xmit failure\n", __func__);
	ff_flushbad:
			/*
			 * Unable to transmit frame that was on the staging
			 * queue.  Reclaim the node reference and other
			 * resources.
			 */
			if (ni != NULL)
				ieee80211_free_node(ni);
			bfstaged->bf_node = NULL;
			if (bfstaged->bf_m != NULL) {
				m_freem(bfstaged->bf_m);
				bfstaged->bf_m = NULL;
			}

			ATH_TXBUF_LOCK(sc);
			STAILQ_INSERT_HEAD(&sc->sc_txbuf, bfstaged, bf_list);
			ATH_TXBUF_UNLOCK(sc);
		} else {
#if 0
			ifp->if_opackets++;
#endif
		}
	} else {
		if (an->an_ff_buf[pri] != NULL) {
			/*
			 * XXX: out-of-order condition only occurs for AP
			 * mode and multicast.  There may be no valid way
			 * to get this condition.
			 */
			DPRINTF(sc, ATH_DEBUG_FF, "[%s] out-of-order frame\n",
				ether_sprintf(an->an_node.ni_macaddr));
			/* XXX stat */
		}
		ATH_TXQ_UNLOCK(txq);
	}
	return m;
}

static struct ath_buf *
_ath_getbuf_locked(struct ath_softc *sc)
{
	struct ath_buf *bf;

	ATH_TXBUF_LOCK_ASSERT(sc);

	bf = STAILQ_FIRST(&sc->sc_txbuf);
	if (bf != NULL && (bf->bf_flags & ATH_BUF_BUSY) == 0)
		STAILQ_REMOVE_HEAD(&sc->sc_txbuf, bf_list);
	else
		bf = NULL;
	if (bf == NULL) {
		DPRINTF(sc, ATH_DEBUG_XMIT, "%s: %s\n", __func__,
		    STAILQ_FIRST(&sc->sc_txbuf) == NULL ?
			"out of xmit buffers" : "xmit buffer busy");
		sc->sc_stats.ast_tx_nobuf++;
	}
	return bf;
}

static struct ath_buf *
ath_getbuf(struct ath_softc *sc)
{
	struct ath_buf *bf;

	ATH_TXBUF_LOCK(sc);
	bf = _ath_getbuf_locked(sc);
	if (bf == NULL) {
		struct ifnet *ifp = sc->sc_ifp;

		DPRINTF(sc, ATH_DEBUG_XMIT, "%s: stop queue\n", __func__);
		sc->sc_stats.ast_tx_qstop++;
		ifp->if_drv_flags |= IFF_DRV_OACTIVE;
	}
	ATH_TXBUF_UNLOCK(sc);
	return bf;
}

/*
 * Cleanup driver resources when we run out of buffers
 * while processing fragments; return the tx buffers
 * allocated and drop node references.
 */
static void
ath_txfrag_cleanup(struct ath_softc *sc,
	ath_bufhead *frags, struct ieee80211_node *ni)
{
	struct ath_buf *bf, *next;

	ATH_TXBUF_LOCK_ASSERT(sc);

	STAILQ_FOREACH_SAFE(bf, frags, bf_list, next) {
		/* NB: bf assumed clean */
		STAILQ_REMOVE_HEAD(frags, bf_list);
		STAILQ_INSERT_HEAD(&sc->sc_txbuf, bf, bf_list);
		ieee80211_node_decref(ni);
	}
}

/*
 * Setup xmit of a fragmented frame.  Allocate a buffer
 * for each frag and bump the node reference count to
 * reflect the held reference to be setup by ath_tx_start.
 */
static int
ath_txfrag_setup(struct ath_softc *sc, ath_bufhead *frags,
	struct mbuf *m0, struct ieee80211_node *ni)
{
	struct mbuf *m;
	struct ath_buf *bf;

	ATH_TXBUF_LOCK(sc);
	for (m = m0->m_nextpkt; m != NULL; m = m->m_nextpkt) {
		bf = _ath_getbuf_locked(sc);
		if (bf == NULL) {	/* out of buffers, cleanup */
			ath_txfrag_cleanup(sc, frags, ni);
			break;
		}
		ieee80211_node_incref(ni);
		STAILQ_INSERT_TAIL(frags, bf, bf_list);
	}
	ATH_TXBUF_UNLOCK(sc);

	return !STAILQ_EMPTY(frags);
}

static void
ath_start(struct ifnet *ifp)
{
	struct ath_softc *sc = ifp->if_softc;
	struct ieee80211_node *ni;
	struct ath_buf *bf;
	struct mbuf *m, *next;
	struct ath_txq *txq;
	ath_bufhead frags;
	int pri;

	if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0 || sc->sc_invalid)
		return;
	for (;;) {
		/*
		 * Grab a TX buffer and associated resources.
		 */
		bf = ath_getbuf(sc);
		if (bf == NULL)
			break;

		IFQ_DEQUEUE(&ifp->if_snd, m);
		if (m == NULL) {
			ATH_TXBUF_LOCK(sc);
			STAILQ_INSERT_HEAD(&sc->sc_txbuf, bf, bf_list);
			ATH_TXBUF_UNLOCK(sc);
			break;
		}
		STAILQ_INIT(&frags);
		ni = (struct ieee80211_node *) m->m_pkthdr.rcvif;
		pri = M_WME_GETAC(m);
		txq = sc->sc_ac2q[pri];
		if (IEEE80211_ATH_CAP(ni->ni_vap, ni, IEEE80211_NODE_FF)) {
			/*
			 * Check queue length; if too deep drop this
			 * frame (tail drop considered good).
			 */
			if (txq->axq_depth >= sc->sc_fftxqmax) {
				DPRINTF(sc, ATH_DEBUG_FF,
				    "[%s] tail drop on q %u depth %u\n",
				    ether_sprintf(ni->ni_macaddr),
				    txq->axq_qnum, txq->axq_depth);
				sc->sc_stats.ast_tx_qfull++;
				m_freem(m);
				goto reclaim;
			}
			m = ath_ff_check(sc, txq, bf, m, ni);
			if (m == NULL) {
				/* NB: ni ref & bf held on stageq */
				continue;
			}
		}
		ifp->if_opackets++;
		/*
		 * Encapsulate the packet in prep for transmission.
		 */
		m = ieee80211_encap(ni, m);
		if (m == NULL) {
			DPRINTF(sc, ATH_DEBUG_XMIT,
			    "%s: encapsulation failure\n", __func__);
			sc->sc_stats.ast_tx_encap++;
			goto bad;
		}
		/*
		 * Check for fragmentation.  If this frame
		 * has been broken up verify we have enough
		 * buffers to send all the fragments so all
		 * go out or none...
		 */
		if ((m->m_flags & M_FRAG) &&
		    !ath_txfrag_setup(sc, &frags, m, ni)) {
			DPRINTF(sc, ATH_DEBUG_XMIT,
			    "%s: out of txfrag buffers\n", __func__);
			sc->sc_stats.ast_tx_nofrag++;
			ath_freetx(m);
			goto bad;
		}
	nextfrag:
		/*
		 * Pass the frame to the h/w for transmission.
		 * Fragmented frames have each frag chained together
		 * with m_nextpkt.  We know there are sufficient ath_buf's
		 * to send all the frags because of work done by
		 * ath_txfrag_setup.  We leave m_nextpkt set while
		 * calling ath_tx_start so it can use it to extend the
		 * the tx duration to cover the subsequent frag and
		 * so it can reclaim all the mbufs in case of an error;
		 * ath_tx_start clears m_nextpkt once it commits to
		 * handing the frame to the hardware.
		 */
		next = m->m_nextpkt;
		if (ath_tx_start(sc, ni, bf, m)) {
	bad:
			ifp->if_oerrors++;
	reclaim:
			bf->bf_m = NULL;
			bf->bf_node = NULL;
			ATH_TXBUF_LOCK(sc);
			STAILQ_INSERT_HEAD(&sc->sc_txbuf, bf, bf_list);
			ath_txfrag_cleanup(sc, &frags, ni);
			ATH_TXBUF_UNLOCK(sc);
			if (ni != NULL)
				ieee80211_free_node(ni);
			continue;
		}
		if (next != NULL) {
			/*
			 * Beware of state changing between frags.
			 * XXX check sta power-save state?
			 */
			if (ni->ni_vap->iv_state != IEEE80211_S_RUN) {
				DPRINTF(sc, ATH_DEBUG_XMIT,
				    "%s: flush fragmented packet, state %s\n",
				    __func__,
				    ieee80211_state_name[ni->ni_vap->iv_state]);
				ath_freetx(next);
				goto reclaim;
			}
			m = next;
			bf = STAILQ_FIRST(&frags);
			KASSERT(bf != NULL, ("no buf for txfrag"));
			STAILQ_REMOVE_HEAD(&frags, bf_list);
			goto nextfrag;
		}

		sc->sc_wd_timer = 5;
#if 0
		/*
		 * Flush stale frames from the fast-frame staging queue.
		 */
		if (ic->ic_opmode != IEEE80211_M_STA)
			ath_ff_stageq_flush(sc, txq, ath_ff_ageflushtestdone);
#endif
	}
}

static int
ath_media_change(struct ifnet *ifp)
{
	int error = ieee80211_media_change(ifp);
	/* NB: only the fixed rate can change and that doesn't need a reset */
	return (error == ENETRESET ? 0 : error);
}

#ifdef ATH_DEBUG
static void
ath_keyprint(struct ath_softc *sc, const char *tag, u_int ix,
	const HAL_KEYVAL *hk, const u_int8_t mac[IEEE80211_ADDR_LEN])
{
	static const char *ciphers[] = {
		"WEP",
		"AES-OCB",
		"AES-CCM",
		"CKIP",
		"TKIP",
		"CLR",
	};
	int i, n;

	printf("%s: [%02u] %-7s ", tag, ix, ciphers[hk->kv_type]);
	for (i = 0, n = hk->kv_len; i < n; i++)
		printf("%02x", hk->kv_val[i]);
	printf(" mac %s", ether_sprintf(mac));
	if (hk->kv_type == HAL_CIPHER_TKIP) {
		printf(" %s ", sc->sc_splitmic ? "mic" : "rxmic");
		for (i = 0; i < sizeof(hk->kv_mic); i++)
			printf("%02x", hk->kv_mic[i]);
		if (!sc->sc_splitmic) {
			printf(" txmic ");
			for (i = 0; i < sizeof(hk->kv_txmic); i++)
				printf("%02x", hk->kv_txmic[i]);
		}
	}
	printf("\n");
}
#endif

/*
 * Set a TKIP key into the hardware.  This handles the
 * potential distribution of key state to multiple key
 * cache slots for TKIP.
 */
static int
ath_keyset_tkip(struct ath_softc *sc, const struct ieee80211_key *k,
	HAL_KEYVAL *hk, const u_int8_t mac[IEEE80211_ADDR_LEN])
{
#define	IEEE80211_KEY_XR	(IEEE80211_KEY_XMIT | IEEE80211_KEY_RECV)
	static const u_int8_t zerobssid[IEEE80211_ADDR_LEN];
	struct ath_hal *ah = sc->sc_ah;

	KASSERT(k->wk_cipher->ic_cipher == IEEE80211_CIPHER_TKIP,
		("got a non-TKIP key, cipher %u", k->wk_cipher->ic_cipher));
	if ((k->wk_flags & IEEE80211_KEY_XR) == IEEE80211_KEY_XR) {
		if (sc->sc_splitmic) {
			/*
			 * TX key goes at first index, RX key at the rx index.
			 * The hal handles the MIC keys at index+64.
			 */
			memcpy(hk->kv_mic, k->wk_txmic, sizeof(hk->kv_mic));
			KEYPRINTF(sc, k->wk_keyix, hk, zerobssid);
			if (!ath_hal_keyset(ah, k->wk_keyix, hk, zerobssid))
				return 0;

			memcpy(hk->kv_mic, k->wk_rxmic, sizeof(hk->kv_mic));
			KEYPRINTF(sc, k->wk_keyix+32, hk, mac);
			/* XXX delete tx key on failure? */
			return ath_hal_keyset(ah, k->wk_keyix+32, hk, mac);
		} else {
			/*
			 * Room for both TX+RX MIC keys in one key cache
			 * slot, just set key at the first index; the hal
			 * will handle the rest.
			 */
			memcpy(hk->kv_mic, k->wk_rxmic, sizeof(hk->kv_mic));
			memcpy(hk->kv_txmic, k->wk_txmic, sizeof(hk->kv_txmic));
			KEYPRINTF(sc, k->wk_keyix, hk, mac);
			return ath_hal_keyset(ah, k->wk_keyix, hk, mac);
		}
	} else if (k->wk_flags & IEEE80211_KEY_XMIT) {
		if (sc->sc_splitmic) {
			/*
			 * NB: must pass MIC key in expected location when
			 * the keycache only holds one MIC key per entry.
			 */
			memcpy(hk->kv_mic, k->wk_txmic, sizeof(hk->kv_txmic));
		} else
			memcpy(hk->kv_txmic, k->wk_txmic, sizeof(hk->kv_txmic));
		KEYPRINTF(sc, k->wk_keyix, hk, mac);
		return ath_hal_keyset(ah, k->wk_keyix, hk, mac);
	} else if (k->wk_flags & IEEE80211_KEY_RECV) {
		memcpy(hk->kv_mic, k->wk_rxmic, sizeof(hk->kv_mic));
		KEYPRINTF(sc, k->wk_keyix, hk, mac);
		return ath_hal_keyset(ah, k->wk_keyix, hk, mac);
	}
	return 0;
#undef IEEE80211_KEY_XR
}

/*
 * Set a net80211 key into the hardware.  This handles the
 * potential distribution of key state to multiple key
 * cache slots for TKIP with hardware MIC support.
 */
static int
ath_keyset(struct ath_softc *sc, const struct ieee80211_key *k,
	struct ieee80211_node *bss)
{
#define	N(a)	(sizeof(a)/sizeof(a[0]))
	static const u_int8_t ciphermap[] = {
		HAL_CIPHER_WEP,		/* IEEE80211_CIPHER_WEP */
		HAL_CIPHER_TKIP,	/* IEEE80211_CIPHER_TKIP */
		HAL_CIPHER_AES_OCB,	/* IEEE80211_CIPHER_AES_OCB */
		HAL_CIPHER_AES_CCM,	/* IEEE80211_CIPHER_AES_CCM */
		(u_int8_t) -1,		/* 4 is not allocated */
		HAL_CIPHER_CKIP,	/* IEEE80211_CIPHER_CKIP */
		HAL_CIPHER_CLR,		/* IEEE80211_CIPHER_NONE */
	};
	struct ath_hal *ah = sc->sc_ah;
	const struct ieee80211_cipher *cip = k->wk_cipher;
	u_int8_t gmac[IEEE80211_ADDR_LEN];
	const u_int8_t *mac;
	HAL_KEYVAL hk;

	memset(&hk, 0, sizeof(hk));
	/*
	 * Software crypto uses a "clear key" so non-crypto
	 * state kept in the key cache are maintained and
	 * so that rx frames have an entry to match.
	 */
	if ((k->wk_flags & IEEE80211_KEY_SWCRYPT) == 0) {
		KASSERT(cip->ic_cipher < N(ciphermap),
			("invalid cipher type %u", cip->ic_cipher));
		hk.kv_type = ciphermap[cip->ic_cipher];
		hk.kv_len = k->wk_keylen;
		memcpy(hk.kv_val, k->wk_key, k->wk_keylen);
	} else
		hk.kv_type = HAL_CIPHER_CLR;

	if ((k->wk_flags & IEEE80211_KEY_GROUP) && sc->sc_mcastkey) {
		/*
		 * Group keys on hardware that supports multicast frame
		 * key search use a mac that is the sender's address with
		 * the high bit set instead of the app-specified address.
		 */
		IEEE80211_ADDR_COPY(gmac, bss->ni_macaddr);
		gmac[0] |= 0x80;
		mac = gmac;
	} else
		mac = k->wk_macaddr;

	if (hk.kv_type == HAL_CIPHER_TKIP &&
	    (k->wk_flags & IEEE80211_KEY_SWMIC) == 0) {
		return ath_keyset_tkip(sc, k, &hk, mac);
	} else {
		KEYPRINTF(sc, k->wk_keyix, &hk, mac);
		return ath_hal_keyset(ah, k->wk_keyix, &hk, mac);
	}
#undef N
}

/*
 * Allocate tx/rx key slots for TKIP.  We allocate two slots for
 * each key, one for decrypt/encrypt and the other for the MIC.
 */
static u_int16_t
key_alloc_2pair(struct ath_softc *sc,
	ieee80211_keyix *txkeyix, ieee80211_keyix *rxkeyix)
{
#define	N(a)	(sizeof(a)/sizeof(a[0]))
	u_int i, keyix;

	KASSERT(sc->sc_splitmic, ("key cache !split"));
	/* XXX could optimize */
	for (i = 0; i < N(sc->sc_keymap)/4; i++) {
		u_int8_t b = sc->sc_keymap[i];
		if (b != 0xff) {
			/*
			 * One or more slots in this byte are free.
			 */
			keyix = i*NBBY;
			while (b & 1) {
		again:
				keyix++;
				b >>= 1;
			}
			/* XXX IEEE80211_KEY_XMIT | IEEE80211_KEY_RECV */
			if (isset(sc->sc_keymap, keyix+32) ||
			    isset(sc->sc_keymap, keyix+64) ||
			    isset(sc->sc_keymap, keyix+32+64)) {
				/* full pair unavailable */
				/* XXX statistic */
				if (keyix == (i+1)*NBBY) {
					/* no slots were appropriate, advance */
					continue;
				}
				goto again;
			}
			setbit(sc->sc_keymap, keyix);
			setbit(sc->sc_keymap, keyix+64);
			setbit(sc->sc_keymap, keyix+32);
			setbit(sc->sc_keymap, keyix+32+64);
			DPRINTF(sc, ATH_DEBUG_KEYCACHE,
				"%s: key pair %u,%u %u,%u\n",
				__func__, keyix, keyix+64,
				keyix+32, keyix+32+64);
			*txkeyix = keyix;
			*rxkeyix = keyix+32;
			return 1;
		}
	}
	DPRINTF(sc, ATH_DEBUG_KEYCACHE, "%s: out of pair space\n", __func__);
	return 0;
#undef N
}

/*
 * Allocate tx/rx key slots for TKIP.  We allocate two slots for
 * each key, one for decrypt/encrypt and the other for the MIC.
 */
static u_int16_t
key_alloc_pair(struct ath_softc *sc,
	ieee80211_keyix *txkeyix, ieee80211_keyix *rxkeyix)
{
#define	N(a)	(sizeof(a)/sizeof(a[0]))
	u_int i, keyix;

	KASSERT(!sc->sc_splitmic, ("key cache split"));
	/* XXX could optimize */
	for (i = 0; i < N(sc->sc_keymap)/4; i++) {
		u_int8_t b = sc->sc_keymap[i];
		if (b != 0xff) {
			/*
			 * One or more slots in this byte are free.
			 */
			keyix = i*NBBY;
			while (b & 1) {
		again:
				keyix++;
				b >>= 1;
			}
			if (isset(sc->sc_keymap, keyix+64)) {
				/* full pair unavailable */
				/* XXX statistic */
				if (keyix == (i+1)*NBBY) {
					/* no slots were appropriate, advance */
					continue;
				}
				goto again;
			}
			setbit(sc->sc_keymap, keyix);
			setbit(sc->sc_keymap, keyix+64);
			DPRINTF(sc, ATH_DEBUG_KEYCACHE,
				"%s: key pair %u,%u\n",
				__func__, keyix, keyix+64);
			*txkeyix = *rxkeyix = keyix;
			return 1;
		}
	}
	DPRINTF(sc, ATH_DEBUG_KEYCACHE, "%s: out of pair space\n", __func__);
	return 0;
#undef N
}

/*
 * Allocate a single key cache slot.
 */
static int
key_alloc_single(struct ath_softc *sc,
	ieee80211_keyix *txkeyix, ieee80211_keyix *rxkeyix)
{
#define	N(a)	(sizeof(a)/sizeof(a[0]))
	u_int i, keyix;

	/* XXX try i,i+32,i+64,i+32+64 to minimize key pair conflicts */
	for (i = 0; i < N(sc->sc_keymap); i++) {
		u_int8_t b = sc->sc_keymap[i];
		if (b != 0xff) {
			/*
			 * One or more slots are free.
			 */
			keyix = i*NBBY;
			while (b & 1)
				keyix++, b >>= 1;
			setbit(sc->sc_keymap, keyix);
			DPRINTF(sc, ATH_DEBUG_KEYCACHE, "%s: key %u\n",
				__func__, keyix);
			*txkeyix = *rxkeyix = keyix;
			return 1;
		}
	}
	DPRINTF(sc, ATH_DEBUG_KEYCACHE, "%s: out of space\n", __func__);
	return 0;
#undef N
}

/*
 * Allocate one or more key cache slots for a uniacst key.  The
 * key itself is needed only to identify the cipher.  For hardware
 * TKIP with split cipher+MIC keys we allocate two key cache slot
 * pairs so that we can setup separate TX and RX MIC keys.  Note
 * that the MIC key for a TKIP key at slot i is assumed by the
 * hardware to be at slot i+64.  This limits TKIP keys to the first
 * 64 entries.
 */
static int
ath_key_alloc(struct ieee80211vap *vap, struct ieee80211_key *k,
	ieee80211_keyix *keyix, ieee80211_keyix *rxkeyix)
{
	struct ath_softc *sc = vap->iv_ic->ic_ifp->if_softc;

	/*
	 * Group key allocation must be handled specially for
	 * parts that do not support multicast key cache search
	 * functionality.  For those parts the key id must match
	 * the h/w key index so lookups find the right key.  On
	 * parts w/ the key search facility we install the sender's
	 * mac address (with the high bit set) and let the hardware
	 * find the key w/o using the key id.  This is preferred as
	 * it permits us to support multiple users for adhoc and/or
	 * multi-station operation.
	 */
	if (k->wk_keyix != IEEE80211_KEYIX_NONE ||	/* global key */
	    ((k->wk_flags & IEEE80211_KEY_GROUP) && !sc->sc_mcastkey)) {
		if (!(&vap->iv_nw_keys[0] <= k &&
		      k < &vap->iv_nw_keys[IEEE80211_WEP_NKID])) {
			/* should not happen */
			DPRINTF(sc, ATH_DEBUG_KEYCACHE,
				"%s: bogus group key\n", __func__);
			return 0;
		}
		/*
		 * XXX we pre-allocate the global keys so
		 * have no way to check if they've already been allocated.
		 */
		*keyix = *rxkeyix = k - vap->iv_nw_keys;
		return 1;
	}

	/*
	 * We allocate two pair for TKIP when using the h/w to do
	 * the MIC.  For everything else, including software crypto,
	 * we allocate a single entry.  Note that s/w crypto requires
	 * a pass-through slot on the 5211 and 5212.  The 5210 does
	 * not support pass-through cache entries and we map all
	 * those requests to slot 0.
	 */
	if (k->wk_flags & IEEE80211_KEY_SWCRYPT) {
		return key_alloc_single(sc, keyix, rxkeyix);
	} else if (k->wk_cipher->ic_cipher == IEEE80211_CIPHER_TKIP &&
	    (k->wk_flags & IEEE80211_KEY_SWMIC) == 0) {
		if (sc->sc_splitmic)
			return key_alloc_2pair(sc, keyix, rxkeyix);
		else
			return key_alloc_pair(sc, keyix, rxkeyix);
	} else {
		return key_alloc_single(sc, keyix, rxkeyix);
	}
}

/*
 * Delete an entry in the key cache allocated by ath_key_alloc.
 */
static int
ath_key_delete(struct ieee80211vap *vap, const struct ieee80211_key *k)
{
	struct ath_softc *sc = vap->iv_ic->ic_ifp->if_softc;
	struct ath_hal *ah = sc->sc_ah;
	const struct ieee80211_cipher *cip = k->wk_cipher;
	u_int keyix = k->wk_keyix;

	DPRINTF(sc, ATH_DEBUG_KEYCACHE, "%s: delete key %u\n", __func__, keyix);

	ath_hal_keyreset(ah, keyix);
	/*
	 * Handle split tx/rx keying required for TKIP with h/w MIC.
	 */
	if (cip->ic_cipher == IEEE80211_CIPHER_TKIP &&
	    (k->wk_flags & IEEE80211_KEY_SWMIC) == 0 && sc->sc_splitmic)
		ath_hal_keyreset(ah, keyix+32);		/* RX key */
	if (keyix >= IEEE80211_WEP_NKID) {
		/*
		 * Don't touch keymap entries for global keys so
		 * they are never considered for dynamic allocation.
		 */
		clrbit(sc->sc_keymap, keyix);
		if (cip->ic_cipher == IEEE80211_CIPHER_TKIP &&
		    (k->wk_flags & IEEE80211_KEY_SWMIC) == 0) {
			clrbit(sc->sc_keymap, keyix+64);	/* TX key MIC */
			if (sc->sc_splitmic) {
				/* +32 for RX key, +32+64 for RX key MIC */
				clrbit(sc->sc_keymap, keyix+32);
				clrbit(sc->sc_keymap, keyix+32+64);
			}
		}
	}
	return 1;
}

/*
 * Set the key cache contents for the specified key.  Key cache
 * slot(s) must already have been allocated by ath_key_alloc.
 */
static int
ath_key_set(struct ieee80211vap *vap, const struct ieee80211_key *k,
	const u_int8_t mac[IEEE80211_ADDR_LEN])
{
	struct ath_softc *sc = vap->iv_ic->ic_ifp->if_softc;

	return ath_keyset(sc, k, vap->iv_bss);
}

/*
 * Block/unblock tx+rx processing while a key change is done.
 * We assume the caller serializes key management operations
 * so we only need to worry about synchronization with other
 * uses that originate in the driver.
 */
static void
ath_key_update_begin(struct ieee80211vap *vap)
{
	struct ifnet *ifp = vap->iv_ic->ic_ifp;
	struct ath_softc *sc = ifp->if_softc;

	DPRINTF(sc, ATH_DEBUG_KEYCACHE, "%s:\n", __func__);
	taskqueue_block(sc->sc_tq);
	IF_LOCK(&ifp->if_snd);		/* NB: doesn't block mgmt frames */
}

static void
ath_key_update_end(struct ieee80211vap *vap)
{
	struct ifnet *ifp = vap->iv_ic->ic_ifp;
	struct ath_softc *sc = ifp->if_softc;

	DPRINTF(sc, ATH_DEBUG_KEYCACHE, "%s:\n", __func__);
	IF_UNLOCK(&ifp->if_snd);
	taskqueue_unblock(sc->sc_tq);
}

/*
 * Calculate the receive filter according to the
 * operating mode and state:
 *
 * o always accept unicast, broadcast, and multicast traffic
 * o accept PHY error frames when hardware doesn't have MIB support
 *   to count and we need them for ANI (sta mode only until recently)
 *   and we are not scanning (ANI is disabled)
 *   NB: older hal's add rx filter bits out of sight and we need to
 *	 blindly preserve them
 * o probe request frames are accepted only when operating in
 *   hostap, adhoc, or monitor modes
 * o enable promiscuous mode
 *   - when in monitor mode
 *   - if interface marked PROMISC (assumes bridge setting is filtered)
 * o accept beacons:
 *   - when operating in station mode for collecting rssi data when
 *     the station is otherwise quiet, or
 *   - when operating in adhoc mode so the 802.11 layer creates
 *     node table entries for peers,
 *   - when scanning
 *   - when doing s/w beacon miss (e.g. for ap+sta)
 *   - when operating in ap mode in 11g to detect overlapping bss that
 *     require protection
 * o accept control frames:
 *   - when in monitor mode
 * XXX BAR frames for 11n
 * XXX HT protection for 11n
 */
static u_int32_t
ath_calcrxfilter(struct ath_softc *sc)
{
	struct ifnet *ifp = sc->sc_ifp;
	struct ieee80211com *ic = ifp->if_l2com;
	u_int32_t rfilt;

	rfilt = HAL_RX_FILTER_UCAST | HAL_RX_FILTER_BCAST | HAL_RX_FILTER_MCAST;
	if (!sc->sc_needmib && !sc->sc_scanning)
		rfilt |= HAL_RX_FILTER_PHYERR;
	if (ic->ic_opmode != IEEE80211_M_STA)
		rfilt |= HAL_RX_FILTER_PROBEREQ;
	if (ic->ic_opmode == IEEE80211_M_MONITOR || (ifp->if_flags & IFF_PROMISC))
		rfilt |= HAL_RX_FILTER_PROM;
	if (ic->ic_opmode == IEEE80211_M_STA ||
	    ic->ic_opmode == IEEE80211_M_IBSS ||
	    sc->sc_swbmiss || sc->sc_scanning)
		rfilt |= HAL_RX_FILTER_BEACON;
	/*
	 * NB: We don't recalculate the rx filter when
	 * ic_protmode changes; otherwise we could do
	 * this only when ic_protmode != NONE.
	 */
	if (ic->ic_opmode == IEEE80211_M_HOSTAP &&
	    IEEE80211_IS_CHAN_ANYG(ic->ic_curchan))
		rfilt |= HAL_RX_FILTER_BEACON;
	if (ic->ic_opmode == IEEE80211_M_MONITOR)
		rfilt |= HAL_RX_FILTER_CONTROL;
	DPRINTF(sc, ATH_DEBUG_MODE, "%s: RX filter 0x%x, %s if_flags 0x%x\n",
	    __func__, rfilt, ieee80211_opmode_name[ic->ic_opmode], ifp->if_flags);
	return rfilt;
}

static void
ath_update_promisc(struct ifnet *ifp)
{
	struct ath_softc *sc = ifp->if_softc;
	u_int32_t rfilt;

	/* configure rx filter */
	rfilt = ath_calcrxfilter(sc);
	ath_hal_setrxfilter(sc->sc_ah, rfilt);

	DPRINTF(sc, ATH_DEBUG_MODE, "%s: RX filter 0x%x\n", __func__, rfilt);
}

static void
ath_update_mcast(struct ifnet *ifp)
{
	struct ath_softc *sc = ifp->if_softc;
	u_int32_t mfilt[2];

	/* calculate and install multicast filter */
	if ((ifp->if_flags & IFF_ALLMULTI) == 0) {
		struct ifmultiaddr *ifma;
		/*
		 * Merge multicast addresses to form the hardware filter.
		 */
		mfilt[0] = mfilt[1] = 0;
		IF_ADDR_LOCK(ifp);	/* XXX need some fiddling to remove? */
		TAILQ_FOREACH(ifma, &ifp->if_multiaddrs, ifma_link) {
			caddr_t dl;
			u_int32_t val;
			u_int8_t pos;

			/* calculate XOR of eight 6bit values */
			dl = LLADDR((struct sockaddr_dl *) ifma->ifma_addr);
			val = LE_READ_4(dl + 0);
			pos = (val >> 18) ^ (val >> 12) ^ (val >> 6) ^ val;
			val = LE_READ_4(dl + 3);
			pos ^= (val >> 18) ^ (val >> 12) ^ (val >> 6) ^ val;
			pos &= 0x3f;
			mfilt[pos / 32] |= (1 << (pos % 32));
		}
		IF_ADDR_UNLOCK(ifp);
	} else
		mfilt[0] = mfilt[1] = ~0;
	ath_hal_setmcastfilter(sc->sc_ah, mfilt[0], mfilt[1]);
	DPRINTF(sc, ATH_DEBUG_MODE, "%s: MC filter %08x:%08x\n",
		__func__, mfilt[0], mfilt[1]);
}

static void
ath_mode_init(struct ath_softc *sc)
{
	struct ifnet *ifp = sc->sc_ifp;
	struct ath_hal *ah = sc->sc_ah;
	u_int32_t rfilt;

	/* configure rx filter */
	rfilt = ath_calcrxfilter(sc);
	ath_hal_setrxfilter(ah, rfilt);

	/* configure operational mode */
	ath_hal_setopmode(ah);

	/* handle any link-level address change */
	ath_hal_setmac(ah, IF_LLADDR(ifp));

	/* calculate and install multicast filter */
	ath_update_mcast(ifp);
}

/*
 * Set the slot time based on the current setting.
 */
static void
ath_setslottime(struct ath_softc *sc)
{
	struct ieee80211com *ic = sc->sc_ifp->if_l2com;
	struct ath_hal *ah = sc->sc_ah;
	u_int usec;

	if (IEEE80211_IS_CHAN_HALF(ic->ic_curchan))
		usec = 13;
	else if (IEEE80211_IS_CHAN_QUARTER(ic->ic_curchan))
		usec = 21;
	else if (IEEE80211_IS_CHAN_ANYG(ic->ic_curchan)) {
		/* honor short/long slot time only in 11g */
		/* XXX shouldn't honor on pure g or turbo g channel */
		if (ic->ic_flags & IEEE80211_F_SHSLOT)
			usec = HAL_SLOT_TIME_9;
		else
			usec = HAL_SLOT_TIME_20;
	} else
		usec = HAL_SLOT_TIME_9;

	DPRINTF(sc, ATH_DEBUG_RESET,
	    "%s: chan %u MHz flags 0x%x %s slot, %u usec\n",
	    __func__, ic->ic_curchan->ic_freq, ic->ic_curchan->ic_flags,
	    ic->ic_flags & IEEE80211_F_SHSLOT ? "short" : "long", usec);

	ath_hal_setslottime(ah, usec);
	sc->sc_updateslot = OK;
}

/*
 * Callback from the 802.11 layer to update the
 * slot time based on the current setting.
 */
static void
ath_updateslot(struct ifnet *ifp)
{
	struct ath_softc *sc = ifp->if_softc;
	struct ieee80211com *ic = ifp->if_l2com;

	/*
	 * When not coordinating the BSS, change the hardware
	 * immediately.  For other operation we defer the change
	 * until beacon updates have propagated to the stations.
	 */
	if (ic->ic_opmode == IEEE80211_M_HOSTAP)
		sc->sc_updateslot = UPDATE;
	else
		ath_setslottime(sc);
}

/*
 * Setup a h/w transmit queue for beacons.
 */
static int
ath_beaconq_setup(struct ath_hal *ah)
{
	HAL_TXQ_INFO qi;

	memset(&qi, 0, sizeof(qi));
	qi.tqi_aifs = HAL_TXQ_USEDEFAULT;
	qi.tqi_cwmin = HAL_TXQ_USEDEFAULT;
	qi.tqi_cwmax = HAL_TXQ_USEDEFAULT;
	/* NB: for dynamic turbo, don't enable any other interrupts */
	qi.tqi_qflags = HAL_TXQ_TXDESCINT_ENABLE;
	return ath_hal_setuptxqueue(ah, HAL_TX_QUEUE_BEACON, &qi);
}

/*
 * Setup the transmit queue parameters for the beacon queue.
 */
static int
ath_beaconq_config(struct ath_softc *sc)
{
#define	ATH_EXPONENT_TO_VALUE(v)	((1<<(v))-1)
	struct ieee80211com *ic = sc->sc_ifp->if_l2com;
	struct ath_hal *ah = sc->sc_ah;
	HAL_TXQ_INFO qi;

	ath_hal_gettxqueueprops(ah, sc->sc_bhalq, &qi);
	if (ic->ic_opmode == IEEE80211_M_HOSTAP) {
		/*
		 * Always burst out beacon and CAB traffic.
		 */
		qi.tqi_aifs = ATH_BEACON_AIFS_DEFAULT;
		qi.tqi_cwmin = ATH_BEACON_CWMIN_DEFAULT;
		qi.tqi_cwmax = ATH_BEACON_CWMAX_DEFAULT;
	} else {
		struct wmeParams *wmep =
			&ic->ic_wme.wme_chanParams.cap_wmeParams[WME_AC_BE];
		/*
		 * Adhoc mode; important thing is to use 2x cwmin.
		 */
		qi.tqi_aifs = wmep->wmep_aifsn;
		qi.tqi_cwmin = 2*ATH_EXPONENT_TO_VALUE(wmep->wmep_logcwmin);
		qi.tqi_cwmax = ATH_EXPONENT_TO_VALUE(wmep->wmep_logcwmax);
	}

	if (!ath_hal_settxqueueprops(ah, sc->sc_bhalq, &qi)) {
		device_printf(sc->sc_dev, "unable to update parameters for "
			"beacon hardware queue!\n");
		return 0;
	} else {
		ath_hal_resettxqueue(ah, sc->sc_bhalq); /* push to h/w */
		return 1;
	}
#undef ATH_EXPONENT_TO_VALUE
}

/*
 * Allocate and setup an initial beacon frame.
 */
static int
ath_beacon_alloc(struct ath_softc *sc, struct ieee80211_node *ni)
{
	struct ieee80211vap *vap = ni->ni_vap;
	struct ath_vap *avp = ATH_VAP(vap);
	struct ath_buf *bf;
	struct mbuf *m;
	int error;

	bf = avp->av_bcbuf;
	if (bf->bf_m != NULL) {
		bus_dmamap_unload(sc->sc_dmat, bf->bf_dmamap);
		m_freem(bf->bf_m);
		bf->bf_m = NULL;
	}
	if (bf->bf_node != NULL) {
		ieee80211_free_node(bf->bf_node);
		bf->bf_node = NULL;
	}

	/*
	 * NB: the beacon data buffer must be 32-bit aligned;
	 * we assume the mbuf routines will return us something
	 * with this alignment (perhaps should assert).
	 */
	m = ieee80211_beacon_alloc(ni, &avp->av_boff);
	if (m == NULL) {
		device_printf(sc->sc_dev, "%s: cannot get mbuf\n", __func__);
		sc->sc_stats.ast_be_nombuf++;
		return ENOMEM;
	}
	error = bus_dmamap_load_mbuf_sg(sc->sc_dmat, bf->bf_dmamap, m,
				     bf->bf_segs, &bf->bf_nseg,
				     BUS_DMA_NOWAIT);
	if (error != 0) {
		device_printf(sc->sc_dev,
		    "%s: cannot map mbuf, bus_dmamap_load_mbuf_sg returns %d\n",
		    __func__, error);
		m_freem(m);
		return error;
	}

	/*
	 * Calculate a TSF adjustment factor required for staggered
	 * beacons.  Note that we assume the format of the beacon
	 * frame leaves the tstamp field immediately following the
	 * header.
	 */
	if (sc->sc_stagbeacons && avp->av_bslot > 0) {
		uint64_t tsfadjust;
		struct ieee80211_frame *wh;

		/*
		 * The beacon interval is in TU's; the TSF is in usecs.
		 * We figure out how many TU's to add to align the timestamp
		 * then convert to TSF units and handle byte swapping before
		 * inserting it in the frame.  The hardware will then add this
		 * each time a beacon frame is sent.  Note that we align vap's
		 * 1..N and leave vap 0 untouched.  This means vap 0 has a
		 * timestamp in one beacon interval while the others get a
		 * timstamp aligned to the next interval.
		 */
		tsfadjust = ni->ni_intval *
		    (ATH_BCBUF - avp->av_bslot) / ATH_BCBUF;
		tsfadjust = htole64(tsfadjust << 10);	/* TU -> TSF */

		DPRINTF(sc, ATH_DEBUG_BEACON,
		    "%s: %s beacons bslot %d intval %u tsfadjust %llu\n",
		    __func__, sc->sc_stagbeacons ? "stagger" : "burst",
		    avp->av_bslot, ni->ni_intval,
		    (long long unsigned) le64toh(tsfadjust));

		wh = mtod(m, struct ieee80211_frame *);
		memcpy(&wh[1], &tsfadjust, sizeof(tsfadjust));
	}
	bf->bf_m = m;
	bf->bf_node = ieee80211_ref_node(ni);

	return 0;
}

/*
 * Setup the beacon frame for transmit.
 */
static void
ath_beacon_setup(struct ath_softc *sc, struct ath_buf *bf)
{
#define	USE_SHPREAMBLE(_ic) \
	(((_ic)->ic_flags & (IEEE80211_F_SHPREAMBLE | IEEE80211_F_USEBARKER))\
		== IEEE80211_F_SHPREAMBLE)
	struct ieee80211_node *ni = bf->bf_node;
	struct ieee80211com *ic = ni->ni_ic;
	struct mbuf *m = bf->bf_m;
	struct ath_hal *ah = sc->sc_ah;
	struct ath_desc *ds;
	int flags, antenna;
	const HAL_RATE_TABLE *rt;
	u_int8_t rix, rate;

	DPRINTF(sc, ATH_DEBUG_BEACON_PROC, "%s: m %p len %u\n",
		__func__, m, m->m_len);

	/* setup descriptors */
	ds = bf->bf_desc;

	flags = HAL_TXDESC_NOACK;
	if (ic->ic_opmode == IEEE80211_M_IBSS && sc->sc_hasveol) {
		ds->ds_link = bf->bf_daddr;	/* self-linked */
		flags |= HAL_TXDESC_VEOL;
		/*
		 * Let hardware handle antenna switching.
		 */
		antenna = sc->sc_txantenna;
	} else {
		ds->ds_link = 0;
		/*
		 * Switch antenna every 4 beacons.
		 * XXX assumes two antenna
		 */
		if (sc->sc_txantenna != 0)
			antenna = sc->sc_txantenna;
		else if (sc->sc_stagbeacons && sc->sc_nbcnvaps != 0)
			antenna = ((sc->sc_stats.ast_be_xmit / sc->sc_nbcnvaps) & 4 ? 2 : 1);
		else
			antenna = (sc->sc_stats.ast_be_xmit & 4 ? 2 : 1);
	}

	KASSERT(bf->bf_nseg == 1,
		("multi-segment beacon frame; nseg %u", bf->bf_nseg));
	ds->ds_data = bf->bf_segs[0].ds_addr;
	/*
	 * Calculate rate code.
	 * XXX everything at min xmit rate
	 */
	rix = 0;
	rt = sc->sc_currates;
	rate = rt->info[rix].rateCode;
	if (USE_SHPREAMBLE(ic))
		rate |= rt->info[rix].shortPreamble;
	ath_hal_setuptxdesc(ah, ds
		, m->m_len + IEEE80211_CRC_LEN	/* frame length */
		, sizeof(struct ieee80211_frame)/* header length */
		, HAL_PKT_TYPE_BEACON		/* Atheros packet type */
		, ni->ni_txpower		/* txpower XXX */
		, rate, 1			/* series 0 rate/tries */
		, HAL_TXKEYIX_INVALID		/* no encryption */
		, antenna			/* antenna mode */
		, flags				/* no ack, veol for beacons */
		, 0				/* rts/cts rate */
		, 0				/* rts/cts duration */
	);
	/* NB: beacon's BufLen must be a multiple of 4 bytes */
	ath_hal_filltxdesc(ah, ds
		, roundup(m->m_len, 4)		/* buffer length */
		, AH_TRUE			/* first segment */
		, AH_TRUE			/* last segment */
		, ds				/* first descriptor */
	);
#if 0
	ath_desc_swap(ds);
#endif
#undef USE_SHPREAMBLE
}

static void
ath_beacon_update(struct ieee80211vap *vap, int item)
{
	struct ieee80211_beacon_offsets *bo = &ATH_VAP(vap)->av_boff;

	setbit(bo->bo_flags, item);
}

/*
 * Append the contents of src to dst; both queues
 * are assumed to be locked.
 */
static void
ath_txqmove(struct ath_txq *dst, struct ath_txq *src)
{
	STAILQ_CONCAT(&dst->axq_q, &src->axq_q);
	dst->axq_link = src->axq_link;
	src->axq_link = NULL;
	dst->axq_depth += src->axq_depth;
	src->axq_depth = 0;
}

/*
 * Transmit a beacon frame at SWBA.  Dynamic updates to the
 * frame contents are done as needed and the slot time is
 * also adjusted based on current state.
 */
static void
ath_beacon_proc(void *arg, int pending)
{
	struct ath_softc *sc = arg;
	struct ath_hal *ah = sc->sc_ah;
	struct ieee80211vap *vap;
	struct ath_buf *bf;
	int slot, otherant;
	uint32_t bfaddr;

	DPRINTF(sc, ATH_DEBUG_BEACON_PROC, "%s: pending %u\n",
		__func__, pending);
	/*
	 * Check if the previous beacon has gone out.  If
	 * not don't try to post another, skip this period
	 * and wait for the next.  Missed beacons indicate
	 * a problem and should not occur.  If we miss too
	 * many consecutive beacons reset the device.
	 */
	if (ath_hal_numtxpending(ah, sc->sc_bhalq) != 0) {
		sc->sc_bmisscount++;
		DPRINTF(sc, ATH_DEBUG_BEACON,
			"%s: missed %u consecutive beacons\n",
			__func__, sc->sc_bmisscount);
		if (sc->sc_bmisscount >= ath_bstuck_threshold)
			taskqueue_enqueue(sc->sc_tq, &sc->sc_bstucktask);
		return;
	}
	if (sc->sc_bmisscount != 0) {
		DPRINTF(sc, ATH_DEBUG_BEACON,
			"%s: resume beacon xmit after %u misses\n",
			__func__, sc->sc_bmisscount);
		sc->sc_bmisscount = 0;
	}

	if (sc->sc_stagbeacons) {			/* staggered beacons */
		struct ieee80211com *ic = sc->sc_ifp->if_l2com;
		uint32_t tsftu;

		tsftu = ath_hal_gettsf32(ah) >> 10;
		/* XXX lintval */
		slot = ((tsftu % ic->ic_lintval) * ATH_BCBUF) / ic->ic_lintval;
		vap = sc->sc_bslot[(slot+1) % ATH_BCBUF];
		bfaddr = 0;
		if (vap != NULL && vap->iv_state == IEEE80211_S_RUN) {
			bf = ath_beacon_generate(sc, vap);
			if (bf != NULL)
				bfaddr = bf->bf_daddr;
		}
	} else {					/* burst'd beacons */
		uint32_t *bflink = &bfaddr;

		for (slot = 0; slot < ATH_BCBUF; slot++) {
			vap = sc->sc_bslot[slot];
			if (vap != NULL && vap->iv_state == IEEE80211_S_RUN) {
				bf = ath_beacon_generate(sc, vap);
				if (bf != NULL) {
					*bflink = bf->bf_daddr;
					bflink = &bf->bf_desc->ds_link;
				}
			}
		}
		*bflink = 0;				/* terminate list */
	}

	/*
	 * Handle slot time change when a non-ERP station joins/leaves
	 * an 11g network.  The 802.11 layer notifies us via callback,
	 * we mark updateslot, then wait one beacon before effecting
	 * the change.  This gives associated stations at least one
	 * beacon interval to note the state change.
	 */
	/* XXX locking */
	if (sc->sc_updateslot == UPDATE) {
		sc->sc_updateslot = COMMIT;	/* commit next beacon */
		sc->sc_slotupdate = slot;
	} else if (sc->sc_updateslot == COMMIT && sc->sc_slotupdate == slot)
		ath_setslottime(sc);		/* commit change to h/w */

	/*
	 * Check recent per-antenna transmit statistics and flip
	 * the default antenna if noticeably more frames went out
	 * on the non-default antenna.
	 * XXX assumes 2 anntenae
	 */
	if (!sc->sc_diversity && (!sc->sc_stagbeacons || slot == 0)) {
		otherant = sc->sc_defant & 1 ? 2 : 1;
		if (sc->sc_ant_tx[otherant] > sc->sc_ant_tx[sc->sc_defant] + 2)
			ath_setdefantenna(sc, otherant);
		sc->sc_ant_tx[1] = sc->sc_ant_tx[2] = 0;
	}

	if (bfaddr != 0) {
		/*
		 * Stop any current dma and put the new frame on the queue.
		 * This should never fail since we check above that no frames
		 * are still pending on the queue.
		 */
		if (!ath_hal_stoptxdma(ah, sc->sc_bhalq)) {
			DPRINTF(sc, ATH_DEBUG_ANY,
				"%s: beacon queue %u did not stop?\n",
				__func__, sc->sc_bhalq);
		}
		/* NB: cabq traffic should already be queued and primed */
		ath_hal_puttxbuf(ah, sc->sc_bhalq, bfaddr);
		ath_hal_txstart(ah, sc->sc_bhalq);

		sc->sc_stats.ast_be_xmit++;
	}
}

static struct ath_buf *
ath_beacon_generate(struct ath_softc *sc, struct ieee80211vap *vap)
{
	struct ath_vap *avp = ATH_VAP(vap);
	struct ath_txq *cabq = sc->sc_cabq;
	struct ath_buf *bf;
	struct mbuf *m;
	int nmcastq, error;

	KASSERT(vap->iv_state == IEEE80211_S_RUN,
	    ("not running, state %d", vap->iv_state));
	KASSERT(avp->av_bcbuf != NULL, ("no beacon buffer"));

	/*
	 * Update dynamic beacon contents.  If this returns
	 * non-zero then we need to remap the memory because
	 * the beacon frame changed size (probably because
	 * of the TIM bitmap).
	 */
	bf = avp->av_bcbuf;
	m = bf->bf_m;
	nmcastq = avp->av_mcastq.axq_depth;
	if (ieee80211_beacon_update(bf->bf_node, &avp->av_boff, m, nmcastq)) {
		/* XXX too conservative? */
		bus_dmamap_unload(sc->sc_dmat, bf->bf_dmamap);
		error = bus_dmamap_load_mbuf_sg(sc->sc_dmat, bf->bf_dmamap, m,
					     bf->bf_segs, &bf->bf_nseg,
					     BUS_DMA_NOWAIT);
		if (error != 0) {
			if_printf(vap->iv_ifp,
			    "%s: bus_dmamap_load_mbuf_sg failed, error %u\n",
			    __func__, error);
			return NULL;
		}
	}
	if ((avp->av_boff.bo_tim[4] & 1) && cabq->axq_depth) {
		DPRINTF(sc, ATH_DEBUG_BEACON,
		    "%s: cabq did not drain, mcastq %u cabq %u\n",
		    __func__, nmcastq, cabq->axq_depth);
		sc->sc_stats.ast_cabq_busy++;
		if (sc->sc_nvaps > 1 && sc->sc_stagbeacons) {
			/*
			 * CABQ traffic from a previous vap is still pending.
			 * We must drain the q before this beacon frame goes
			 * out as otherwise this vap's stations will get cab
			 * frames from a different vap.
			 * XXX could be slow causing us to miss DBA
			 */
			ath_tx_draintxq(sc, cabq);
		}
	}
	ath_beacon_setup(sc, bf);
	bus_dmamap_sync(sc->sc_dmat, bf->bf_dmamap, BUS_DMASYNC_PREWRITE);

	/*
	 * Enable the CAB queue before the beacon queue to
	 * insure cab frames are triggered by this beacon.
	 */
	if (avp->av_boff.bo_tim[4] & 1) {
		struct ath_hal *ah = sc->sc_ah;

		/* NB: only at DTIM */
		ATH_TXQ_LOCK(cabq);
		ATH_TXQ_LOCK(&avp->av_mcastq);
		if (nmcastq) {
			struct ath_buf *bfm;

			/*
			 * Move frames from the s/w mcast q to the h/w cab q.
			 * XXX MORE_DATA bit
			 */
			bfm = STAILQ_FIRST(&avp->av_mcastq.axq_q);
			if (cabq->axq_link != NULL) {
				*cabq->axq_link = bfm->bf_daddr;
			} else
				ath_hal_puttxbuf(ah, cabq->axq_qnum,
					bfm->bf_daddr);
			ath_txqmove(cabq, &avp->av_mcastq);

			sc->sc_stats.ast_cabq_xmit += nmcastq;
		}
		/* NB: gated by beacon so safe to start here */
		ath_hal_txstart(ah, cabq->axq_qnum);
		ATH_TXQ_UNLOCK(cabq);
		ATH_TXQ_UNLOCK(&avp->av_mcastq);
	}
	return bf;
}

static void
ath_beacon_start_adhoc(struct ath_softc *sc, struct ieee80211vap *vap)
{
	struct ath_vap *avp = ATH_VAP(vap);
	struct ath_hal *ah = sc->sc_ah;
	struct ath_buf *bf;
	struct mbuf *m;
	int error;

	KASSERT(avp->av_bcbuf != NULL, ("no beacon buffer"));

	/*
	 * Update dynamic beacon contents.  If this returns
	 * non-zero then we need to remap the memory because
	 * the beacon frame changed size (probably because
	 * of the TIM bitmap).
	 */
	bf = avp->av_bcbuf;
	m = bf->bf_m;
	if (ieee80211_beacon_update(bf->bf_node, &avp->av_boff, m, 0)) {
		/* XXX too conservative? */
		bus_dmamap_unload(sc->sc_dmat, bf->bf_dmamap);
		error = bus_dmamap_load_mbuf_sg(sc->sc_dmat, bf->bf_dmamap, m,
					     bf->bf_segs, &bf->bf_nseg,
					     BUS_DMA_NOWAIT);
		if (error != 0) {
			if_printf(vap->iv_ifp,
			    "%s: bus_dmamap_load_mbuf_sg failed, error %u\n",
			    __func__, error);
			return;
		}
	}
	ath_beacon_setup(sc, bf);
	bus_dmamap_sync(sc->sc_dmat, bf->bf_dmamap, BUS_DMASYNC_PREWRITE);

	/* NB: caller is known to have already stopped tx dma */
	ath_hal_puttxbuf(ah, sc->sc_bhalq, bf->bf_daddr);
	ath_hal_txstart(ah, sc->sc_bhalq);
}

/*
 * Reset the hardware after detecting beacons have stopped.
 */
static void
ath_bstuck_proc(void *arg, int pending)
{
	struct ath_softc *sc = arg;
	struct ifnet *ifp = sc->sc_ifp;

	if_printf(ifp, "stuck beacon; resetting (bmiss count %u)\n",
		sc->sc_bmisscount);
	sc->sc_stats.ast_bstuck++;
	ath_reset(ifp);
}

/*
 * Reclaim beacon resources and return buffer to the pool.
 */
static void
ath_beacon_return(struct ath_softc *sc, struct ath_buf *bf)
{

	if (bf->bf_m != NULL) {
		bus_dmamap_unload(sc->sc_dmat, bf->bf_dmamap);
		m_freem(bf->bf_m);
		bf->bf_m = NULL;
	}
	if (bf->bf_node != NULL) {
		ieee80211_free_node(bf->bf_node);
		bf->bf_node = NULL;
	}
	STAILQ_INSERT_TAIL(&sc->sc_bbuf, bf, bf_list);
}

/*
 * Reclaim beacon resources.
 */
static void
ath_beacon_free(struct ath_softc *sc)
{
	struct ath_buf *bf;

	STAILQ_FOREACH(bf, &sc->sc_bbuf, bf_list) {
		if (bf->bf_m != NULL) {
			bus_dmamap_unload(sc->sc_dmat, bf->bf_dmamap);
			m_freem(bf->bf_m);
			bf->bf_m = NULL;
		}
		if (bf->bf_node != NULL) {
			ieee80211_free_node(bf->bf_node);
			bf->bf_node = NULL;
		}
	}
}

/*
 * Configure the beacon and sleep timers.
 *
 * When operating as an AP this resets the TSF and sets
 * up the hardware to notify us when we need to issue beacons.
 *
 * When operating in station mode this sets up the beacon
 * timers according to the timestamp of the last received
 * beacon and the current TSF, configures PCF and DTIM
 * handling, programs the sleep registers so the hardware
 * will wakeup in time to receive beacons, and configures
 * the beacon miss handling so we'll receive a BMISS
 * interrupt when we stop seeing beacons from the AP
 * we've associated with.
 */
static void
ath_beacon_config(struct ath_softc *sc, struct ieee80211vap *vap)
{
#define	TSF_TO_TU(_h,_l) \
	((((u_int32_t)(_h)) << 22) | (((u_int32_t)(_l)) >> 10))
#define	FUDGE	2
	struct ath_hal *ah = sc->sc_ah;
	struct ieee80211com *ic = sc->sc_ifp->if_l2com;
	struct ieee80211_node *ni;
	u_int32_t nexttbtt, intval, tsftu;
	u_int64_t tsf;

	if (vap == NULL)
		vap = TAILQ_FIRST(&ic->ic_vaps);	/* XXX */
	ni = vap->iv_bss;

	/* extract tstamp from last beacon and convert to TU */
	nexttbtt = TSF_TO_TU(LE_READ_4(ni->ni_tstamp.data + 4),
			     LE_READ_4(ni->ni_tstamp.data));
	if (ic->ic_opmode == IEEE80211_M_HOSTAP) {
		/*
		 * For multi-bss ap support beacons are either staggered
		 * evenly over N slots or burst together.  For the former
		 * arrange for the SWBA to be delivered for each slot.
		 * Slots that are not occupied will generate nothing.
		 */
		/* NB: the beacon interval is kept internally in TU's */
		intval = ni->ni_intval & HAL_BEACON_PERIOD;
		if (sc->sc_stagbeacons)
			intval /= ATH_BCBUF;
	} else {
		/* NB: the beacon interval is kept internally in TU's */
		intval = ni->ni_intval & HAL_BEACON_PERIOD;
	}
	if (nexttbtt == 0)		/* e.g. for ap mode */
		nexttbtt = intval;
	else if (intval)		/* NB: can be 0 for monitor mode */
		nexttbtt = roundup(nexttbtt, intval);
	DPRINTF(sc, ATH_DEBUG_BEACON, "%s: nexttbtt %u intval %u (%u)\n",
		__func__, nexttbtt, intval, ni->ni_intval);
	if (ic->ic_opmode == IEEE80211_M_STA && !sc->sc_swbmiss) {
		HAL_BEACON_STATE bs;
		int dtimperiod, dtimcount;
		int cfpperiod, cfpcount;

		/*
		 * Setup dtim and cfp parameters according to
		 * last beacon we received (which may be none).
		 */
		dtimperiod = ni->ni_dtim_period;
		if (dtimperiod <= 0)		/* NB: 0 if not known */
			dtimperiod = 1;
		dtimcount = ni->ni_dtim_count;
		if (dtimcount >= dtimperiod)	/* NB: sanity check */
			dtimcount = 0;		/* XXX? */
		cfpperiod = 1;			/* NB: no PCF support yet */
		cfpcount = 0;
		/*
		 * Pull nexttbtt forward to reflect the current
		 * TSF and calculate dtim+cfp state for the result.
		 */
		tsf = ath_hal_gettsf64(ah);
		tsftu = TSF_TO_TU(tsf>>32, tsf) + FUDGE;
		do {
			nexttbtt += intval;
			if (--dtimcount < 0) {
				dtimcount = dtimperiod - 1;
				if (--cfpcount < 0)
					cfpcount = cfpperiod - 1;
			}
		} while (nexttbtt < tsftu);
		memset(&bs, 0, sizeof(bs));
		bs.bs_intval = intval;
		bs.bs_nexttbtt = nexttbtt;
		bs.bs_dtimperiod = dtimperiod*intval;
		bs.bs_nextdtim = bs.bs_nexttbtt + dtimcount*intval;
		bs.bs_cfpperiod = cfpperiod*bs.bs_dtimperiod;
		bs.bs_cfpnext = bs.bs_nextdtim + cfpcount*bs.bs_dtimperiod;
		bs.bs_cfpmaxduration = 0;
#if 0
		/*
		 * The 802.11 layer records the offset to the DTIM
		 * bitmap while receiving beacons; use it here to
		 * enable h/w detection of our AID being marked in
		 * the bitmap vector (to indicate frames for us are
		 * pending at the AP).
		 * XXX do DTIM handling in s/w to WAR old h/w bugs
		 * XXX enable based on h/w rev for newer chips
		 */
		bs.bs_timoffset = ni->ni_timoff;
#endif
		/*
		 * Calculate the number of consecutive beacons to miss
		 * before taking a BMISS interrupt.
		 * Note that we clamp the result to at most 10 beacons.
		 */
		bs.bs_bmissthreshold = vap->iv_bmissthreshold;
		if (bs.bs_bmissthreshold > 10)
			bs.bs_bmissthreshold = 10;
		else if (bs.bs_bmissthreshold <= 0)
			bs.bs_bmissthreshold = 1;

		/*
		 * Calculate sleep duration.  The configuration is
		 * given in ms.  We insure a multiple of the beacon
		 * period is used.  Also, if the sleep duration is
		 * greater than the DTIM period then it makes senses
		 * to make it a multiple of that.
		 *
		 * XXX fixed at 100ms
		 */
		bs.bs_sleepduration =
			roundup(IEEE80211_MS_TO_TU(100), bs.bs_intval);
		if (bs.bs_sleepduration > bs.bs_dtimperiod)
			bs.bs_sleepduration = roundup(bs.bs_sleepduration, bs.bs_dtimperiod);

		DPRINTF(sc, ATH_DEBUG_BEACON,
			"%s: tsf %ju tsf:tu %u intval %u nexttbtt %u dtim %u nextdtim %u bmiss %u sleep %u cfp:period %u maxdur %u next %u timoffset %u\n"
			, __func__
			, tsf, tsftu
			, bs.bs_intval
			, bs.bs_nexttbtt
			, bs.bs_dtimperiod
			, bs.bs_nextdtim
			, bs.bs_bmissthreshold
			, bs.bs_sleepduration
			, bs.bs_cfpperiod
			, bs.bs_cfpmaxduration
			, bs.bs_cfpnext
			, bs.bs_timoffset
		);
		ath_hal_intrset(ah, 0);
		ath_hal_beacontimers(ah, &bs);
		sc->sc_imask |= HAL_INT_BMISS;
		ath_hal_intrset(ah, sc->sc_imask);
	} else {
		ath_hal_intrset(ah, 0);
		if (nexttbtt == intval)
			intval |= HAL_BEACON_RESET_TSF;
		if (ic->ic_opmode == IEEE80211_M_IBSS) {
			/*
			 * In IBSS mode enable the beacon timers but only
			 * enable SWBA interrupts if we need to manually
			 * prepare beacon frames.  Otherwise we use a
			 * self-linked tx descriptor and let the hardware
			 * deal with things.
			 */
			intval |= HAL_BEACON_ENA;
			if (!sc->sc_hasveol)
				sc->sc_imask |= HAL_INT_SWBA;
			if ((intval & HAL_BEACON_RESET_TSF) == 0) {
				/*
				 * Pull nexttbtt forward to reflect
				 * the current TSF.
				 */
				tsf = ath_hal_gettsf64(ah);
				tsftu = TSF_TO_TU(tsf>>32, tsf) + FUDGE;
				do {
					nexttbtt += intval;
				} while (nexttbtt < tsftu);
			}
			ath_beaconq_config(sc);
		} else if (ic->ic_opmode == IEEE80211_M_HOSTAP) {
			/*
			 * In AP mode we enable the beacon timers and
			 * SWBA interrupts to prepare beacon frames.
			 */
			intval |= HAL_BEACON_ENA;
			sc->sc_imask |= HAL_INT_SWBA;	/* beacon prepare */
			ath_beaconq_config(sc);
		}
		ath_hal_beaconinit(ah, nexttbtt, intval);
		sc->sc_bmisscount = 0;
		ath_hal_intrset(ah, sc->sc_imask);
		/*
		 * When using a self-linked beacon descriptor in
		 * ibss mode load it once here.
		 */
		if (ic->ic_opmode == IEEE80211_M_IBSS && sc->sc_hasveol)
			ath_beacon_start_adhoc(sc, vap);
	}
	sc->sc_syncbeacon = 0;
#undef FUDGE
#undef TSF_TO_TU
}

static void
ath_load_cb(void *arg, bus_dma_segment_t *segs, int nsegs, int error)
{
	bus_addr_t *paddr = (bus_addr_t*) arg;
	KASSERT(error == 0, ("error %u on bus_dma callback", error));
	*paddr = segs->ds_addr;
}

static int
ath_descdma_setup(struct ath_softc *sc,
	struct ath_descdma *dd, ath_bufhead *head,
	const char *name, int nbuf, int ndesc)
{
#define	DS2PHYS(_dd, _ds) \
	((_dd)->dd_desc_paddr + ((caddr_t)(_ds) - (caddr_t)(_dd)->dd_desc))
	struct ifnet *ifp = sc->sc_ifp;
	struct ath_desc *ds;
	struct ath_buf *bf;
	int i, bsize, error;

	DPRINTF(sc, ATH_DEBUG_RESET, "%s: %s DMA: %u buffers %u desc/buf\n",
	    __func__, name, nbuf, ndesc);

	dd->dd_name = name;
	dd->dd_desc_len = sizeof(struct ath_desc) * nbuf * ndesc;

	/*
	 * Setup DMA descriptor area.
	 */
	error = bus_dma_tag_create(bus_get_dma_tag(sc->sc_dev),	/* parent */
		       PAGE_SIZE, 0,		/* alignment, bounds */
		       BUS_SPACE_MAXADDR_32BIT,	/* lowaddr */
		       BUS_SPACE_MAXADDR,	/* highaddr */
		       NULL, NULL,		/* filter, filterarg */
		       dd->dd_desc_len,		/* maxsize */
		       1,			/* nsegments */
		       dd->dd_desc_len,		/* maxsegsize */
		       BUS_DMA_ALLOCNOW,	/* flags */
		       NULL,			/* lockfunc */
		       NULL,			/* lockarg */
		       &dd->dd_dmat);
	if (error != 0) {
		if_printf(ifp, "cannot allocate %s DMA tag\n", dd->dd_name);
		return error;
	}

	/* allocate descriptors */
	error = bus_dmamap_create(dd->dd_dmat, BUS_DMA_NOWAIT, &dd->dd_dmamap);
	if (error != 0) {
		if_printf(ifp, "unable to create dmamap for %s descriptors, "
			"error %u\n", dd->dd_name, error);
		goto fail0;
	}

	error = bus_dmamem_alloc(dd->dd_dmat, (void**) &dd->dd_desc,
				 BUS_DMA_NOWAIT | BUS_DMA_COHERENT,
				 &dd->dd_dmamap);
	if (error != 0) {
		if_printf(ifp, "unable to alloc memory for %u %s descriptors, "
			"error %u\n", nbuf * ndesc, dd->dd_name, error);
		goto fail1;
	}

	error = bus_dmamap_load(dd->dd_dmat, dd->dd_dmamap,
				dd->dd_desc, dd->dd_desc_len,
				ath_load_cb, &dd->dd_desc_paddr,
				BUS_DMA_NOWAIT);
	if (error != 0) {
		if_printf(ifp, "unable to map %s descriptors, error %u\n",
			dd->dd_name, error);
		goto fail2;
	}

	ds = dd->dd_desc;
	DPRINTF(sc, ATH_DEBUG_RESET, "%s: %s DMA map: %p (%lu) -> %p (%lu)\n",
	    __func__, dd->dd_name, ds, (u_long) dd->dd_desc_len,
	    (caddr_t) dd->dd_desc_paddr, /*XXX*/ (u_long) dd->dd_desc_len);

	/* allocate rx buffers */
	bsize = sizeof(struct ath_buf) * nbuf;
	bf = malloc(bsize, M_ATHDEV, M_NOWAIT | M_ZERO);
	if (bf == NULL) {
		if_printf(ifp, "malloc of %s buffers failed, size %u\n",
			dd->dd_name, bsize);
		goto fail3;
	}
	dd->dd_bufptr = bf;

	STAILQ_INIT(head);
	for (i = 0; i < nbuf; i++, bf++, ds += ndesc) {
		bf->bf_desc = ds;
		bf->bf_daddr = DS2PHYS(dd, ds);
		error = bus_dmamap_create(sc->sc_dmat, BUS_DMA_NOWAIT,
				&bf->bf_dmamap);
		if (error != 0) {
			if_printf(ifp, "unable to create dmamap for %s "
				"buffer %u, error %u\n", dd->dd_name, i, error);
			ath_descdma_cleanup(sc, dd, head);
			return error;
		}
		STAILQ_INSERT_TAIL(head, bf, bf_list);
	}
	return 0;
fail3:
	bus_dmamap_unload(dd->dd_dmat, dd->dd_dmamap);
fail2:
	bus_dmamem_free(dd->dd_dmat, dd->dd_desc, dd->dd_dmamap);
fail1:
	bus_dmamap_destroy(dd->dd_dmat, dd->dd_dmamap);
fail0:
	bus_dma_tag_destroy(dd->dd_dmat);
	memset(dd, 0, sizeof(*dd));
	return error;
#undef DS2PHYS
}

static void
ath_descdma_cleanup(struct ath_softc *sc,
	struct ath_descdma *dd, ath_bufhead *head)
{
	struct ath_buf *bf;
	struct ieee80211_node *ni;

	bus_dmamap_unload(dd->dd_dmat, dd->dd_dmamap);
	bus_dmamem_free(dd->dd_dmat, dd->dd_desc, dd->dd_dmamap);
	bus_dmamap_destroy(dd->dd_dmat, dd->dd_dmamap);
	bus_dma_tag_destroy(dd->dd_dmat);

	STAILQ_FOREACH(bf, head, bf_list) {
		if (bf->bf_m) {
			m_freem(bf->bf_m);
			bf->bf_m = NULL;
		}
		if (bf->bf_dmamap != NULL) {
			bus_dmamap_destroy(sc->sc_dmat, bf->bf_dmamap);
			bf->bf_dmamap = NULL;
		}
		ni = bf->bf_node;
		bf->bf_node = NULL;
		if (ni != NULL) {
			/*
			 * Reclaim node reference.
			 */
			ieee80211_free_node(ni);
		}
	}

	STAILQ_INIT(head);
	free(dd->dd_bufptr, M_ATHDEV);
	memset(dd, 0, sizeof(*dd));
}

static int
ath_desc_alloc(struct ath_softc *sc)
{
	int error;

	error = ath_descdma_setup(sc, &sc->sc_rxdma, &sc->sc_rxbuf,
			"rx", ath_rxbuf, 1);
	if (error != 0)
		return error;

	error = ath_descdma_setup(sc, &sc->sc_txdma, &sc->sc_txbuf,
			"tx", ath_txbuf, ATH_TXDESC);
	if (error != 0) {
		ath_descdma_cleanup(sc, &sc->sc_rxdma, &sc->sc_rxbuf);
		return error;
	}

	error = ath_descdma_setup(sc, &sc->sc_bdma, &sc->sc_bbuf,
			"beacon", ATH_BCBUF, 1);
	if (error != 0) {
		ath_descdma_cleanup(sc, &sc->sc_txdma, &sc->sc_txbuf);
		ath_descdma_cleanup(sc, &sc->sc_rxdma, &sc->sc_rxbuf);
		return error;
	}
	return 0;
}

static void
ath_desc_free(struct ath_softc *sc)
{

	if (sc->sc_bdma.dd_desc_len != 0)
		ath_descdma_cleanup(sc, &sc->sc_bdma, &sc->sc_bbuf);
	if (sc->sc_txdma.dd_desc_len != 0)
		ath_descdma_cleanup(sc, &sc->sc_txdma, &sc->sc_txbuf);
	if (sc->sc_rxdma.dd_desc_len != 0)
		ath_descdma_cleanup(sc, &sc->sc_rxdma, &sc->sc_rxbuf);
}

static struct ieee80211_node *
ath_node_alloc(struct ieee80211vap *vap, const uint8_t mac[IEEE80211_ADDR_LEN])
{
	struct ieee80211com *ic = vap->iv_ic;
	struct ath_softc *sc = ic->ic_ifp->if_softc;
	const size_t space = sizeof(struct ath_node) + sc->sc_rc->arc_space;
	struct ath_node *an;

	an = malloc(space, M_80211_NODE, M_NOWAIT|M_ZERO);
	if (an == NULL) {
		/* XXX stat+msg */
		return NULL;
	}
	ath_rate_node_init(sc, an);

	DPRINTF(sc, ATH_DEBUG_NODE, "%s: an %p\n", __func__, an);
	return &an->an_node;
}

static void
ath_node_free(struct ieee80211_node *ni)
{
	struct ieee80211com *ic = ni->ni_ic;
        struct ath_softc *sc = ic->ic_ifp->if_softc;

	DPRINTF(sc, ATH_DEBUG_NODE, "%s: ni %p\n", __func__, ni);

	ath_rate_node_cleanup(sc, ATH_NODE(ni));
	sc->sc_node_free(ni);
}

static void
ath_node_getsignal(const struct ieee80211_node *ni, int8_t *rssi, int8_t *noise)
{
	struct ieee80211com *ic = ni->ni_ic;
	struct ath_softc *sc = ic->ic_ifp->if_softc;
	struct ath_hal *ah = sc->sc_ah;

	*rssi = ic->ic_node_getrssi(ni);
	if (ni->ni_chan != IEEE80211_CHAN_ANYC)
		*noise = ath_hal_getchannoise(ah, ni->ni_chan);
	else
		*noise = -95;		/* nominally correct */
}

static int
ath_rxbuf_init(struct ath_softc *sc, struct ath_buf *bf)
{
	struct ath_hal *ah = sc->sc_ah;
	int error;
	struct mbuf *m;
	struct ath_desc *ds;

	m = bf->bf_m;
	if (m == NULL) {
		/*
		 * NB: by assigning a page to the rx dma buffer we
		 * implicitly satisfy the Atheros requirement that
		 * this buffer be cache-line-aligned and sized to be
		 * multiple of the cache line size.  Not doing this
		 * causes weird stuff to happen (for the 5210 at least).
		 */
		m = m_getcl(M_DONTWAIT, MT_DATA, M_PKTHDR);
		if (m == NULL) {
			DPRINTF(sc, ATH_DEBUG_ANY,
				"%s: no mbuf/cluster\n", __func__);
			sc->sc_stats.ast_rx_nombuf++;
			return ENOMEM;
		}
		m->m_pkthdr.len = m->m_len = m->m_ext.ext_size;

		error = bus_dmamap_load_mbuf_sg(sc->sc_dmat,
					     bf->bf_dmamap, m,
					     bf->bf_segs, &bf->bf_nseg,
					     BUS_DMA_NOWAIT);
		if (error != 0) {
			DPRINTF(sc, ATH_DEBUG_ANY,
			    "%s: bus_dmamap_load_mbuf_sg failed; error %d\n",
			    __func__, error);
			sc->sc_stats.ast_rx_busdma++;
			m_freem(m);
			return error;
		}
		KASSERT(bf->bf_nseg == 1,
			("multi-segment packet; nseg %u", bf->bf_nseg));
		bf->bf_m = m;
	}
	bus_dmamap_sync(sc->sc_dmat, bf->bf_dmamap, BUS_DMASYNC_PREREAD);

	/*
	 * Setup descriptors.  For receive we always terminate
	 * the descriptor list with a self-linked entry so we'll
	 * not get overrun under high load (as can happen with a
	 * 5212 when ANI processing enables PHY error frames).
	 *
	 * To insure the last descriptor is self-linked we create
	 * each descriptor as self-linked and add it to the end.  As
	 * each additional descriptor is added the previous self-linked
	 * entry is ``fixed'' naturally.  This should be safe even
	 * if DMA is happening.  When processing RX interrupts we
	 * never remove/process the last, self-linked, entry on the
	 * descriptor list.  This insures the hardware always has
	 * someplace to write a new frame.
	 */
	ds = bf->bf_desc;
	ds->ds_link = bf->bf_daddr;	/* link to self */
	ds->ds_data = bf->bf_segs[0].ds_addr;
	ath_hal_setuprxdesc(ah, ds
		, m->m_len		/* buffer size */
		, 0
	);

	if (sc->sc_rxlink != NULL)
		*sc->sc_rxlink = bf->bf_daddr;
	sc->sc_rxlink = &ds->ds_link;
	return 0;
}

/*
 * Extend 15-bit time stamp from rx descriptor to
 * a full 64-bit TSF using the specified TSF.
 */
static __inline u_int64_t
ath_extend_tsf(u_int32_t rstamp, u_int64_t tsf)
{
	if ((tsf & 0x7fff) < rstamp)
		tsf -= 0x8000;
	return ((tsf &~ 0x7fff) | rstamp);
}

/*
 * Intercept management frames to collect beacon rssi data
 * and to do ibss merges.
 */
static void
ath_recv_mgmt(struct ieee80211_node *ni, struct mbuf *m,
	int subtype, int rssi, int noise, u_int32_t rstamp)
{
	struct ieee80211vap *vap = ni->ni_vap;
	struct ath_softc *sc = vap->iv_ic->ic_ifp->if_softc;

	/*
	 * Call up first so subsequent work can use information
	 * potentially stored in the node (e.g. for ibss merge).
	 */
	ATH_VAP(vap)->av_recv_mgmt(ni, m, subtype, rssi, noise, rstamp);
	switch (subtype) {
	case IEEE80211_FC0_SUBTYPE_BEACON:
		/* update rssi statistics for use by the hal */
		ATH_RSSI_LPF(sc->sc_halstats.ns_avgbrssi, rssi);
		if (sc->sc_syncbeacon &&
		    ni == vap->iv_bss && vap->iv_state == IEEE80211_S_RUN) {
			/*
			 * Resync beacon timers using the tsf of the beacon
			 * frame we just received.
			 */
			ath_beacon_config(sc, vap);
		}
		/* fall thru... */
	case IEEE80211_FC0_SUBTYPE_PROBE_RESP:
		if (vap->iv_opmode == IEEE80211_M_IBSS &&
		    vap->iv_state == IEEE80211_S_RUN) {
			u_int64_t tsf = ath_extend_tsf(rstamp,
				ath_hal_gettsf64(sc->sc_ah));
			/*
			 * Handle ibss merge as needed; check the tsf on the
			 * frame before attempting the merge.  The 802.11 spec
			 * says the station should change it's bssid to match
			 * the oldest station with the same ssid, where oldest
			 * is determined by the tsf.  Note that hardware
			 * reconfiguration happens through callback to
			 * ath_newstate as the state machine will go from
			 * RUN -> RUN when this happens.
			 */
			if (le64toh(ni->ni_tstamp.tsf) >= tsf) {
				DPRINTF(sc, ATH_DEBUG_STATE,
				    "ibss merge, rstamp %u tsf %ju "
				    "tstamp %ju\n", rstamp, (uintmax_t)tsf,
				    (uintmax_t)ni->ni_tstamp.tsf);
				(void) ieee80211_ibss_merge(ni);
			}
		}
		break;
	}
}

/*
 * Set the default antenna.
 */
static void
ath_setdefantenna(struct ath_softc *sc, u_int antenna)
{
	struct ath_hal *ah = sc->sc_ah;

	/* XXX block beacon interrupts */
	ath_hal_setdefantenna(ah, antenna);
	if (sc->sc_defant != antenna)
		sc->sc_stats.ast_ant_defswitch++;
	sc->sc_defant = antenna;
	sc->sc_rxotherant = 0;
}

static int
ath_rx_tap(struct ifnet *ifp, struct mbuf *m,
	const struct ath_rx_status *rs, u_int64_t tsf, int16_t nf)
{
#define	CHAN_HT20	htole32(IEEE80211_CHAN_HT20)
#define	CHAN_HT40U	htole32(IEEE80211_CHAN_HT40U)
#define	CHAN_HT40D	htole32(IEEE80211_CHAN_HT40D)
#define	CHAN_HT		(CHAN_HT20|CHAN_HT40U|CHAN_HT40D)
	struct ath_softc *sc = ifp->if_softc;
	const HAL_RATE_TABLE *rt;
	uint8_t rix;

	/*
	 * Discard anything shorter than an ack or cts.
	 */
	if (m->m_pkthdr.len < IEEE80211_ACK_LEN) {
		DPRINTF(sc, ATH_DEBUG_RECV, "%s: runt packet %d\n",
			__func__, m->m_pkthdr.len);
		sc->sc_stats.ast_rx_tooshort++;
		return 0;
	}
	rt = sc->sc_currates;
	KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode));
	rix = rt->rateCodeToIndex[rs->rs_rate];
	sc->sc_rx_th.wr_rate = sc->sc_hwmap[rix].ieeerate;
	sc->sc_rx_th.wr_flags = sc->sc_hwmap[rix].rxflags;
#ifdef AH_SUPPORT_AR5416
	sc->sc_rx_th.wr_chan_flags &= ~CHAN_HT;
	if (sc->sc_rx_th.wr_rate & IEEE80211_RATE_MCS) {	/* HT rate */
		struct ieee80211com *ic = ifp->if_l2com;

		if ((rs->rs_flags & HAL_RX_2040) == 0)
			sc->sc_rx_th.wr_chan_flags |= CHAN_HT20;
		else if (IEEE80211_IS_CHAN_HT40U(ic->ic_curchan))
			sc->sc_rx_th.wr_chan_flags |= CHAN_HT40U;
		else
			sc->sc_rx_th.wr_chan_flags |= CHAN_HT40D;
		if ((rs->rs_flags & HAL_RX_GI) == 0)
			sc->sc_rx_th.wr_flags |= IEEE80211_RADIOTAP_F_SHORTGI;
	}
#endif
	sc->sc_rx_th.wr_tsf = htole64(ath_extend_tsf(rs->rs_tstamp, tsf));
	if (rs->rs_status & HAL_RXERR_CRC)
		sc->sc_rx_th.wr_flags |= IEEE80211_RADIOTAP_F_BADFCS;
	/* XXX propagate other error flags from descriptor */
	sc->sc_rx_th.wr_antsignal = rs->rs_rssi + nf;
	sc->sc_rx_th.wr_antnoise = nf;
	sc->sc_rx_th.wr_antenna = rs->rs_antenna;

	bpf_mtap2(ifp->if_bpf, &sc->sc_rx_th, sc->sc_rx_th_len, m);

	return 1;
#undef CHAN_HT
#undef CHAN_HT20
#undef CHAN_HT40U
#undef CHAN_HT40D
}

static void
ath_handle_micerror(struct ieee80211com *ic,
	struct ieee80211_frame *wh, int keyix)
{
	struct ieee80211_node *ni;

	/* XXX recheck MIC to deal w/ chips that lie */
	/* XXX discard MIC errors on !data frames */
	ni = ieee80211_find_rxnode(ic, (const struct ieee80211_frame_min *) wh);
	if (ni != NULL) {
		ieee80211_notify_michael_failure(ni->ni_vap, wh, keyix);
		ieee80211_free_node(ni);
	}
}

static void
ath_rx_proc(void *arg, int npending)
{
#define	PA2DESC(_sc, _pa) \
	((struct ath_desc *)((caddr_t)(_sc)->sc_rxdma.dd_desc + \
		((_pa) - (_sc)->sc_rxdma.dd_desc_paddr)))
	struct ath_softc *sc = arg;
	struct ath_buf *bf;
	struct ifnet *ifp = sc->sc_ifp;
	struct ieee80211com *ic = ifp->if_l2com;
	struct ath_hal *ah = sc->sc_ah;
	struct ath_desc *ds;
	struct ath_rx_status *rs;
	struct mbuf *m;
	struct ieee80211_node *ni;
	int len, type, ngood;
	u_int phyerr;
	HAL_STATUS status;
	int16_t nf;
	u_int64_t tsf;

	DPRINTF(sc, ATH_DEBUG_RX_PROC, "%s: pending %u\n", __func__, npending);
	ngood = 0;
	nf = ath_hal_getchannoise(ah, sc->sc_curchan);
	sc->sc_stats.ast_rx_noise = nf;
	tsf = ath_hal_gettsf64(ah);
	do {
		bf = STAILQ_FIRST(&sc->sc_rxbuf);
		if (bf == NULL) {		/* NB: shouldn't happen */
			if_printf(ifp, "%s: no buffer!\n", __func__);
			break;
		}
		m = bf->bf_m;
		if (m == NULL) {		/* NB: shouldn't happen */
			/*
			 * If mbuf allocation failed previously there
			 * will be no mbuf; try again to re-populate it.
			 */
			/* XXX make debug msg */
			if_printf(ifp, "%s: no mbuf!\n", __func__);
			STAILQ_REMOVE_HEAD(&sc->sc_rxbuf, bf_list);
			goto rx_next;
		}
		ds = bf->bf_desc;
		if (ds->ds_link == bf->bf_daddr) {
			/* NB: never process the self-linked entry at the end */
			break;
		}
		/* XXX sync descriptor memory */
		/*
		 * Must provide the virtual address of the current
		 * descriptor, the physical address, and the virtual
		 * address of the next descriptor in the h/w chain.
		 * This allows the HAL to look ahead to see if the
		 * hardware is done with a descriptor by checking the
		 * done bit in the following descriptor and the address
		 * of the current descriptor the DMA engine is working
		 * on.  All this is necessary because of our use of
		 * a self-linked list to avoid rx overruns.
		 */
		rs = &bf->bf_status.ds_rxstat;
		status = ath_hal_rxprocdesc(ah, ds,
				bf->bf_daddr, PA2DESC(sc, ds->ds_link), rs);
#ifdef ATH_DEBUG
		if (sc->sc_debug & ATH_DEBUG_RECV_DESC)
			ath_printrxbuf(sc, bf, 0, status == HAL_OK);
#endif
		if (status == HAL_EINPROGRESS)
			break;
		STAILQ_REMOVE_HEAD(&sc->sc_rxbuf, bf_list);
		if (rs->rs_status != 0) {
			if (rs->rs_status & HAL_RXERR_CRC)
				sc->sc_stats.ast_rx_crcerr++;
			if (rs->rs_status & HAL_RXERR_FIFO)
				sc->sc_stats.ast_rx_fifoerr++;
			if (rs->rs_status & HAL_RXERR_PHY) {
				sc->sc_stats.ast_rx_phyerr++;
				phyerr = rs->rs_phyerr & 0x1f;
				sc->sc_stats.ast_rx_phy[phyerr]++;
				goto rx_error;	/* NB: don't count in ierrors */
			}
			if (rs->rs_status & HAL_RXERR_DECRYPT) {
				/*
				 * Decrypt error.  If the error occurred
				 * because there was no hardware key, then
				 * let the frame through so the upper layers
				 * can process it.  This is necessary for 5210
				 * parts which have no way to setup a ``clear''
				 * key cache entry.
				 *
				 * XXX do key cache faulting
				 */
				if (rs->rs_keyix == HAL_RXKEYIX_INVALID)
					goto rx_accept;
				sc->sc_stats.ast_rx_badcrypt++;
			}
			if (rs->rs_status & HAL_RXERR_MIC) {
				sc->sc_stats.ast_rx_badmic++;
				/*
				 * Do minimal work required to hand off
				 * the 802.11 header for notifcation.
				 */
				/* XXX frag's and qos frames */
				len = rs->rs_datalen;
				if (len >= sizeof (struct ieee80211_frame)) {
					bus_dmamap_sync(sc->sc_dmat,
					    bf->bf_dmamap,
					    BUS_DMASYNC_POSTREAD);
					ath_handle_micerror(ic,
					    mtod(m, struct ieee80211_frame *),
					    sc->sc_splitmic ?
						rs->rs_keyix-32 : rs->rs_keyix);
				}
			}
			ifp->if_ierrors++;
rx_error:
			/*
			 * Cleanup any pending partial frame.
			 */
			if (sc->sc_rxpending != NULL) {
				m_freem(sc->sc_rxpending);
				sc->sc_rxpending = NULL;
			}
			/*
			 * When a tap is present pass error frames
			 * that have been requested.  By default we
			 * pass decrypt+mic errors but others may be
			 * interesting (e.g. crc).
			 */
			if (bpf_peers_present(ifp->if_bpf) &&
			    (rs->rs_status & sc->sc_monpass)) {
				bus_dmamap_sync(sc->sc_dmat, bf->bf_dmamap,
				    BUS_DMASYNC_POSTREAD);
				/* NB: bpf needs the mbuf length setup */
				len = rs->rs_datalen;
				m->m_pkthdr.len = m->m_len = len;
				(void) ath_rx_tap(ifp, m, rs, tsf, nf);
			}
			/* XXX pass MIC errors up for s/w reclaculation */
			goto rx_next;
		}
rx_accept:
		/*
		 * Sync and unmap the frame.  At this point we're
		 * committed to passing the mbuf somewhere so clear
		 * bf_m; this means a new mbuf must be allocated
		 * when the rx descriptor is setup again to receive
		 * another frame.
		 */
		bus_dmamap_sync(sc->sc_dmat, bf->bf_dmamap,
		    BUS_DMASYNC_POSTREAD);
		bus_dmamap_unload(sc->sc_dmat, bf->bf_dmamap);
		bf->bf_m = NULL;

		len = rs->rs_datalen;
		m->m_len = len;

		if (rs->rs_more) {
			/*
			 * Frame spans multiple descriptors; save
			 * it for the next completed descriptor, it
			 * will be used to construct a jumbogram.
			 */
			if (sc->sc_rxpending != NULL) {
				/* NB: max frame size is currently 2 clusters */
				sc->sc_stats.ast_rx_toobig++;
				m_freem(sc->sc_rxpending);
			}
			m->m_pkthdr.rcvif = ifp;
			m->m_pkthdr.len = len;
			sc->sc_rxpending = m;
			goto rx_next;
		} else if (sc->sc_rxpending != NULL) {
			/*
			 * This is the second part of a jumbogram,
			 * chain it to the first mbuf, adjust the
			 * frame length, and clear the rxpending state.
			 */
			sc->sc_rxpending->m_next = m;
			sc->sc_rxpending->m_pkthdr.len += len;
			m = sc->sc_rxpending;
			sc->sc_rxpending = NULL;
		} else {
			/*
			 * Normal single-descriptor receive; setup
			 * the rcvif and packet length.
			 */
			m->m_pkthdr.rcvif = ifp;
			m->m_pkthdr.len = len;
		}

		ifp->if_ipackets++;
		sc->sc_stats.ast_ant_rx[rs->rs_antenna]++;

		if (bpf_peers_present(ifp->if_bpf) &&
		    !ath_rx_tap(ifp, m, rs, tsf, nf)) {
			m_freem(m);		/* XXX reclaim */
			goto rx_next;
		}

		/*
		 * From this point on we assume the frame is at least
		 * as large as ieee80211_frame_min; verify that.
		 */
		if (len < IEEE80211_MIN_LEN) {
			DPRINTF(sc, ATH_DEBUG_RECV, "%s: short packet %d\n",
				__func__, len);
			sc->sc_stats.ast_rx_tooshort++;
			m_freem(m);
			goto rx_next;
		}

		if (IFF_DUMPPKTS(sc, ATH_DEBUG_RECV)) {
			const HAL_RATE_TABLE *rt = sc->sc_currates;
			uint8_t rix = rt->rateCodeToIndex[rs->rs_rate];

			ieee80211_dump_pkt(ic, mtod(m, caddr_t), len,
			    sc->sc_hwmap[rix].ieeerate, rs->rs_rssi);
		}

		m_adj(m, -IEEE80211_CRC_LEN);

		/*
		 * Locate the node for sender, track state, and then
		 * pass the (referenced) node up to the 802.11 layer
		 * for its use.
		 */
		ni = ieee80211_find_rxnode_withkey(ic,
			mtod(m, const struct ieee80211_frame_min *),
			rs->rs_keyix == HAL_RXKEYIX_INVALID ?
				IEEE80211_KEYIX_NONE : rs->rs_keyix);
		if (ni != NULL) {
			/*
			 * Sending station is known, dispatch directly.
			 */
#ifdef IEEE80211_SUPPORT_TDMA
			sc->sc_tdmars = rs;
#endif
			type = ieee80211_input(ni, m,
			    rs->rs_rssi, nf, rs->rs_tstamp);
			ieee80211_free_node(ni);
			/*
			 * Arrange to update the last rx timestamp only for
			 * frames from our ap when operating in station mode.
			 * This assumes the rx key is always setup when
			 * associated.
			 */
			if (ic->ic_opmode == IEEE80211_M_STA &&
			    rs->rs_keyix != HAL_RXKEYIX_INVALID)
				ngood++;
		} else {
			type = ieee80211_input_all(ic, m,
			    rs->rs_rssi, nf, rs->rs_tstamp);
		}
		/*
		 * Track rx rssi and do any rx antenna management.
		 */
		ATH_RSSI_LPF(sc->sc_halstats.ns_avgrssi, rs->rs_rssi);
		if (sc->sc_diversity) {
			/*
			 * When using fast diversity, change the default rx
			 * antenna if diversity chooses the other antenna 3
			 * times in a row.
			 */
			if (sc->sc_defant != rs->rs_antenna) {
				if (++sc->sc_rxotherant >= 3)
					ath_setdefantenna(sc, rs->rs_antenna);
			} else
				sc->sc_rxotherant = 0;
		}
		if (sc->sc_softled) {
			/*
			 * Blink for any data frame.  Otherwise do a
			 * heartbeat-style blink when idle.  The latter
			 * is mainly for station mode where we depend on
			 * periodic beacon frames to trigger the poll event.
			 */
			if (type == IEEE80211_FC0_TYPE_DATA) {
				const HAL_RATE_TABLE *rt = sc->sc_currates;
				ath_led_event(sc,
				    rt->rateCodeToIndex[rs->rs_rate]);
			} else if (ticks - sc->sc_ledevent >= sc->sc_ledidle)
				ath_led_event(sc, 0);
		}
rx_next:
		STAILQ_INSERT_TAIL(&sc->sc_rxbuf, bf, bf_list);
	} while (ath_rxbuf_init(sc, bf) == 0);

	/* rx signal state monitoring */
	ath_hal_rxmonitor(ah, &sc->sc_halstats, sc->sc_curchan);
	if (ngood)
		sc->sc_lastrx = tsf;

	if ((ifp->if_drv_flags & IFF_DRV_OACTIVE) == 0 &&
	    !IFQ_IS_EMPTY(&ifp->if_snd))
		ath_start(ifp);

#undef PA2DESC
}

static void
ath_txq_init(struct ath_softc *sc, struct ath_txq *txq, int qnum)
{
	txq->axq_qnum = qnum;
	txq->axq_depth = 0;
	txq->axq_intrcnt = 0;
	txq->axq_link = NULL;
	STAILQ_INIT(&txq->axq_q);
	ATH_TXQ_LOCK_INIT(sc, txq);
	TAILQ_INIT(&txq->axq_stageq);
	txq->axq_curage = 0;
}

/*
 * Setup a h/w transmit queue.
 */
static struct ath_txq *
ath_txq_setup(struct ath_softc *sc, int qtype, int subtype)
{
#define	N(a)	(sizeof(a)/sizeof(a[0]))
	struct ath_hal *ah = sc->sc_ah;
	HAL_TXQ_INFO qi;
	int qnum;

	memset(&qi, 0, sizeof(qi));
	qi.tqi_subtype = subtype;
	qi.tqi_aifs = HAL_TXQ_USEDEFAULT;
	qi.tqi_cwmin = HAL_TXQ_USEDEFAULT;
	qi.tqi_cwmax = HAL_TXQ_USEDEFAULT;
	/*
	 * Enable interrupts only for EOL and DESC conditions.
	 * We mark tx descriptors to receive a DESC interrupt
	 * when a tx queue gets deep; otherwise waiting for the
	 * EOL to reap descriptors.  Note that this is done to
	 * reduce interrupt load and this only defers reaping
	 * descriptors, never transmitting frames.  Aside from
	 * reducing interrupts this also permits more concurrency.
	 * The only potential downside is if the tx queue backs
	 * up in which case the top half of the kernel may backup
	 * due to a lack of tx descriptors.
	 */
	qi.tqi_qflags = HAL_TXQ_TXEOLINT_ENABLE | HAL_TXQ_TXDESCINT_ENABLE;
	qnum = ath_hal_setuptxqueue(ah, qtype, &qi);
	if (qnum == -1) {
		/*
		 * NB: don't print a message, this happens
		 * normally on parts with too few tx queues
		 */
		return NULL;
	}
	if (qnum >= N(sc->sc_txq)) {
		device_printf(sc->sc_dev,
			"hal qnum %u out of range, max %zu!\n",
			qnum, N(sc->sc_txq));
		ath_hal_releasetxqueue(ah, qnum);
		return NULL;
	}
	if (!ATH_TXQ_SETUP(sc, qnum)) {
		ath_txq_init(sc, &sc->sc_txq[qnum], qnum);
		sc->sc_txqsetup |= 1<<qnum;
	}
	return &sc->sc_txq[qnum];
#undef N
}

/*
 * Setup a hardware data transmit queue for the specified
 * access control.  The hal may not support all requested
 * queues in which case it will return a reference to a
 * previously setup queue.  We record the mapping from ac's
 * to h/w queues for use by ath_tx_start and also track
 * the set of h/w queues being used to optimize work in the
 * transmit interrupt handler and related routines.
 */
static int
ath_tx_setup(struct ath_softc *sc, int ac, int haltype)
{
#define	N(a)	(sizeof(a)/sizeof(a[0]))
	struct ath_txq *txq;

	if (ac >= N(sc->sc_ac2q)) {
		device_printf(sc->sc_dev, "AC %u out of range, max %zu!\n",
			ac, N(sc->sc_ac2q));
		return 0;
	}
	txq = ath_txq_setup(sc, HAL_TX_QUEUE_DATA, haltype);
	if (txq != NULL) {
		sc->sc_ac2q[ac] = txq;
		return 1;
	} else
		return 0;
#undef N
}

/*
 * Update WME parameters for a transmit queue.
 */
static int
ath_txq_update(struct ath_softc *sc, int ac)
{
#define	ATH_EXPONENT_TO_VALUE(v)	((1<<v)-1)
#define	ATH_TXOP_TO_US(v)		(v<<5)
	struct ifnet *ifp = sc->sc_ifp;
	struct ieee80211com *ic = ifp->if_l2com;
	struct ath_txq *txq = sc->sc_ac2q[ac];
	struct wmeParams *wmep = &ic->ic_wme.wme_chanParams.cap_wmeParams[ac];
	struct ath_hal *ah = sc->sc_ah;
	HAL_TXQ_INFO qi;

	ath_hal_gettxqueueprops(ah, txq->axq_qnum, &qi);
#ifdef IEEE80211_SUPPORT_TDMA
	if (sc->sc_tdma) {
		/*
		 * AIFS is zero so there's no pre-transmit wait.  The
		 * burst time defines the slot duration and is configured
		 * via sysctl.  The QCU is setup to not do post-xmit
		 * back off, lockout all lower-priority QCU's, and fire
		 * off the DMA beacon alert timer which is setup based
		 * on the slot configuration.
		 */
		qi.tqi_qflags = HAL_TXQ_TXOKINT_ENABLE
			      | HAL_TXQ_TXERRINT_ENABLE
			      | HAL_TXQ_TXURNINT_ENABLE
			      | HAL_TXQ_TXEOLINT_ENABLE
			      | HAL_TXQ_DBA_GATED
			      | HAL_TXQ_BACKOFF_DISABLE
			      | HAL_TXQ_ARB_LOCKOUT_GLOBAL
			      ;
		qi.tqi_aifs = 0;
		/* XXX +dbaprep? */
		qi.tqi_readyTime = sc->sc_tdmaslotlen;
		qi.tqi_burstTime = qi.tqi_readyTime;
	} else {
#endif
		qi.tqi_qflags = HAL_TXQ_TXOKINT_ENABLE
			      | HAL_TXQ_TXERRINT_ENABLE
			      | HAL_TXQ_TXDESCINT_ENABLE
			      | HAL_TXQ_TXURNINT_ENABLE
			      ;
		qi.tqi_aifs = wmep->wmep_aifsn;
		qi.tqi_cwmin = ATH_EXPONENT_TO_VALUE(wmep->wmep_logcwmin);
		qi.tqi_cwmax = ATH_EXPONENT_TO_VALUE(wmep->wmep_logcwmax);
		qi.tqi_readyTime = 0;
		qi.tqi_burstTime = ATH_TXOP_TO_US(wmep->wmep_txopLimit);
#ifdef IEEE80211_SUPPORT_TDMA
	}
#endif

	DPRINTF(sc, ATH_DEBUG_RESET,
	    "%s: Q%u qflags 0x%x aifs %u cwmin %u cwmax %u burstTime %u\n",
	    __func__, txq->axq_qnum, qi.tqi_qflags,
	    qi.tqi_aifs, qi.tqi_cwmin, qi.tqi_cwmax, qi.tqi_burstTime);

	if (!ath_hal_settxqueueprops(ah, txq->axq_qnum, &qi)) {
		if_printf(ifp, "unable to update hardware queue "
			"parameters for %s traffic!\n",
			ieee80211_wme_acnames[ac]);
		return 0;
	} else {
		ath_hal_resettxqueue(ah, txq->axq_qnum); /* push to h/w */
		return 1;
	}
#undef ATH_TXOP_TO_US
#undef ATH_EXPONENT_TO_VALUE
}

/*
 * Callback from the 802.11 layer to update WME parameters.
 */
static int
ath_wme_update(struct ieee80211com *ic)
{
	struct ath_softc *sc = ic->ic_ifp->if_softc;

	return !ath_txq_update(sc, WME_AC_BE) ||
	    !ath_txq_update(sc, WME_AC_BK) ||
	    !ath_txq_update(sc, WME_AC_VI) ||
	    !ath_txq_update(sc, WME_AC_VO) ? EIO : 0;
}

/*
 * Reclaim resources for a setup queue.
 */
static void
ath_tx_cleanupq(struct ath_softc *sc, struct ath_txq *txq)
{

	ath_hal_releasetxqueue(sc->sc_ah, txq->axq_qnum);
	ATH_TXQ_LOCK_DESTROY(txq);
	sc->sc_txqsetup &= ~(1<<txq->axq_qnum);
}

/*
 * Reclaim all tx queue resources.
 */
static void
ath_tx_cleanup(struct ath_softc *sc)
{
	int i;

	ATH_TXBUF_LOCK_DESTROY(sc);
	for (i = 0; i < HAL_NUM_TX_QUEUES; i++)
		if (ATH_TXQ_SETUP(sc, i))
			ath_tx_cleanupq(sc, &sc->sc_txq[i]);
}

/*
 * Return h/w rate index for an IEEE rate (w/o basic rate bit).
 */
static int
ath_tx_findrix(const HAL_RATE_TABLE *rt, int rate)
{
	int i;

	for (i = 0; i < rt->rateCount; i++)
		if ((rt->info[i].dot11Rate & IEEE80211_RATE_VAL) == rate)
			return i;
	return 0;		/* NB: lowest rate */
}

/*
 * Reclaim mbuf resources.  For fragmented frames we
 * need to claim each frag chained with m_nextpkt.
 */
static void
ath_freetx(struct mbuf *m)
{
	struct mbuf *next;

	do {
		next = m->m_nextpkt;
		m->m_nextpkt = NULL;
		m_freem(m);
	} while ((m = next) != NULL);
}

static int
ath_tx_dmasetup(struct ath_softc *sc, struct ath_buf *bf, struct mbuf *m0)
{
	struct mbuf *m;
	int error;

	/*
	 * Load the DMA map so any coalescing is done.  This
	 * also calculates the number of descriptors we need.
	 */
	error = bus_dmamap_load_mbuf_sg(sc->sc_dmat, bf->bf_dmamap, m0,
				     bf->bf_segs, &bf->bf_nseg,
				     BUS_DMA_NOWAIT);
	if (error == EFBIG) {
		/* XXX packet requires too many descriptors */
		bf->bf_nseg = ATH_TXDESC+1;
	} else if (error != 0) {
		sc->sc_stats.ast_tx_busdma++;
		ath_freetx(m0);
		return error;
	}
	/*
	 * Discard null packets and check for packets that
	 * require too many TX descriptors.  We try to convert
	 * the latter to a cluster.
	 */
	if (bf->bf_nseg > ATH_TXDESC) {		/* too many desc's, linearize */
		sc->sc_stats.ast_tx_linear++;
		m = m_collapse(m0, M_DONTWAIT, ATH_TXDESC);
		if (m == NULL) {
			ath_freetx(m0);
			sc->sc_stats.ast_tx_nombuf++;
			return ENOMEM;
		}
		m0 = m;
		error = bus_dmamap_load_mbuf_sg(sc->sc_dmat, bf->bf_dmamap, m0,
					     bf->bf_segs, &bf->bf_nseg,
					     BUS_DMA_NOWAIT);
		if (error != 0) {
			sc->sc_stats.ast_tx_busdma++;
			ath_freetx(m0);
			return error;
		}
		KASSERT(bf->bf_nseg <= ATH_TXDESC,
		    ("too many segments after defrag; nseg %u", bf->bf_nseg));
	} else if (bf->bf_nseg == 0) {		/* null packet, discard */
		sc->sc_stats.ast_tx_nodata++;
		ath_freetx(m0);
		return EIO;
	}
	DPRINTF(sc, ATH_DEBUG_XMIT, "%s: m %p len %u\n",
		__func__, m0, m0->m_pkthdr.len);
	bus_dmamap_sync(sc->sc_dmat, bf->bf_dmamap, BUS_DMASYNC_PREWRITE);
	bf->bf_m = m0;

	return 0;
}

static void
ath_tx_handoff(struct ath_softc *sc, struct ath_txq *txq, struct ath_buf *bf)
{
	struct ath_hal *ah = sc->sc_ah;
	struct ath_desc *ds, *ds0;
	int i;

	/*
	 * Fillin the remainder of the descriptor info.
	 */
	ds0 = ds = bf->bf_desc;
	for (i = 0; i < bf->bf_nseg; i++, ds++) {
		ds->ds_data = bf->bf_segs[i].ds_addr;
		if (i == bf->bf_nseg - 1)
			ds->ds_link = 0;
		else
			ds->ds_link = bf->bf_daddr + sizeof(*ds) * (i + 1);
		ath_hal_filltxdesc(ah, ds
			, bf->bf_segs[i].ds_len	/* segment length */
			, i == 0		/* first segment */
			, i == bf->bf_nseg - 1	/* last segment */
			, ds0			/* first descriptor */
		);
		DPRINTF(sc, ATH_DEBUG_XMIT,
			"%s: %d: %08x %08x %08x %08x %08x %08x\n",
			__func__, i, ds->ds_link, ds->ds_data,
			ds->ds_ctl0, ds->ds_ctl1, ds->ds_hw[0], ds->ds_hw[1]);
	}
	/*
	 * Insert the frame on the outbound list and pass it on
	 * to the hardware.  Multicast frames buffered for power
	 * save stations and transmit from the CAB queue are stored
	 * on a s/w only queue and loaded on to the CAB queue in
	 * the SWBA handler since frames only go out on DTIM and
	 * to avoid possible races.
	 */
	ATH_TXQ_LOCK(txq);
	KASSERT((bf->bf_flags & ATH_BUF_BUSY) == 0,
	     ("busy status 0x%x", bf->bf_flags));
	if (txq->axq_qnum != ATH_TXQ_SWQ) {
#ifdef IEEE80211_SUPPORT_TDMA
		int qbusy;

		ATH_TXQ_INSERT_TAIL(txq, bf, bf_list);
		qbusy = ath_hal_txqenabled(ah, txq->axq_qnum);
		if (txq->axq_link == NULL) {
			/*
			 * Be careful writing the address to TXDP.  If
			 * the tx q is enabled then this write will be
			 * ignored.  Normally this is not an issue but
			 * when tdma is in use and the q is beacon gated
			 * this race can occur.  If the q is busy then
			 * defer the work to later--either when another
			 * packet comes along or when we prepare a beacon
			 * frame at SWBA.
			 */
			if (!qbusy) {
				ath_hal_puttxbuf(ah, txq->axq_qnum, bf->bf_daddr);
				txq->axq_flags &= ~ATH_TXQ_PUTPENDING;
				DPRINTF(sc, ATH_DEBUG_XMIT,
				    "%s: TXDP[%u] = %p (%p) depth %d\n",
				    __func__, txq->axq_qnum,
				    (caddr_t)bf->bf_daddr, bf->bf_desc,
				    txq->axq_depth);
			} else {
				txq->axq_flags |= ATH_TXQ_PUTPENDING;
				DPRINTF(sc, ATH_DEBUG_TDMA | ATH_DEBUG_XMIT,
				    "%s: Q%u busy, defer enable\n", __func__,
				    txq->axq_qnum);
			}
		} else {
			*txq->axq_link = bf->bf_daddr;
			DPRINTF(sc, ATH_DEBUG_XMIT,
			    "%s: link[%u](%p)=%p (%p) depth %d\n", __func__,
			    txq->axq_qnum, txq->axq_link,
			    (caddr_t)bf->bf_daddr, bf->bf_desc, txq->axq_depth);
			if ((txq->axq_flags & ATH_TXQ_PUTPENDING) && !qbusy) {
				/*
				 * The q was busy when we previously tried
				 * to write the address of the first buffer
				 * in the chain.  Since it's not busy now
				 * handle this chore.  We are certain the
				 * buffer at the front is the right one since
				 * axq_link is NULL only when the buffer list
				 * is/was empty.
				 */
				ath_hal_puttxbuf(ah, txq->axq_qnum,
					STAILQ_FIRST(&txq->axq_q)->bf_daddr);
				txq->axq_flags &= ~ATH_TXQ_PUTPENDING;
				DPRINTF(sc, ATH_DEBUG_TDMA | ATH_DEBUG_XMIT,
				    "%s: Q%u restarted\n", __func__,
				    txq->axq_qnum);
			}
		}
#else
		ATH_TXQ_INSERT_TAIL(txq, bf, bf_list);
		if (txq->axq_link == NULL) {
			ath_hal_puttxbuf(ah, txq->axq_qnum, bf->bf_daddr);
			DPRINTF(sc, ATH_DEBUG_XMIT,
			    "%s: TXDP[%u] = %p (%p) depth %d\n",
			    __func__, txq->axq_qnum,
			    (caddr_t)bf->bf_daddr, bf->bf_desc,
			    txq->axq_depth);
		} else {
			*txq->axq_link = bf->bf_daddr;
			DPRINTF(sc, ATH_DEBUG_XMIT,
			    "%s: link[%u](%p)=%p (%p) depth %d\n", __func__,
			    txq->axq_qnum, txq->axq_link,
			    (caddr_t)bf->bf_daddr, bf->bf_desc, txq->axq_depth);
		}
#endif /* IEEE80211_SUPPORT_TDMA */
		txq->axq_link = &bf->bf_desc[bf->bf_nseg - 1].ds_link;
		ath_hal_txstart(ah, txq->axq_qnum);
	} else {
		if (txq->axq_link != NULL) {
			struct ath_buf *last = ATH_TXQ_LAST(txq);
			struct ieee80211_frame *wh;

			/* mark previous frame */
			wh = mtod(last->bf_m, struct ieee80211_frame *);
			wh->i_fc[1] |= IEEE80211_FC1_MORE_DATA;
			bus_dmamap_sync(sc->sc_dmat, last->bf_dmamap,
			    BUS_DMASYNC_PREWRITE);

			/* link descriptor */
			*txq->axq_link = bf->bf_daddr;
		}
		ATH_TXQ_INSERT_TAIL(txq, bf, bf_list);
		txq->axq_link = &bf->bf_desc[bf->bf_nseg - 1].ds_link;
	}
	ATH_TXQ_UNLOCK(txq);
}

static int
ath_tx_start(struct ath_softc *sc, struct ieee80211_node *ni, struct ath_buf *bf,
    struct mbuf *m0)
{
	struct ieee80211vap *vap = ni->ni_vap;
	struct ath_vap *avp = ATH_VAP(vap);
	struct ath_hal *ah = sc->sc_ah;
	struct ifnet *ifp = sc->sc_ifp;
	struct ieee80211com *ic = ifp->if_l2com;
	const struct chanAccParams *cap = &ic->ic_wme.wme_chanParams;
	int error, iswep, ismcast, isfrag, ismrr;
	int keyix, hdrlen, pktlen, try0;
	u_int8_t rix, txrate, ctsrate;
	u_int8_t cix = 0xff;		/* NB: silence compiler */
	struct ath_desc *ds;
	struct ath_txq *txq;
	struct ieee80211_frame *wh;
	u_int subtype, flags, ctsduration;
	HAL_PKT_TYPE atype;
	const HAL_RATE_TABLE *rt;
	HAL_BOOL shortPreamble;
	struct ath_node *an;
	u_int pri;

	wh = mtod(m0, struct ieee80211_frame *);
	iswep = wh->i_fc[1] & IEEE80211_FC1_WEP;
	ismcast = IEEE80211_IS_MULTICAST(wh->i_addr1);
	isfrag = m0->m_flags & M_FRAG;
	hdrlen = ieee80211_anyhdrsize(wh);
	/*
	 * Packet length must not include any
	 * pad bytes; deduct them here.
	 */
	pktlen = m0->m_pkthdr.len - (hdrlen & 3);

	if (iswep) {
		const struct ieee80211_cipher *cip;
		struct ieee80211_key *k;

		/*
		 * Construct the 802.11 header+trailer for an encrypted
		 * frame. The only reason this can fail is because of an
		 * unknown or unsupported cipher/key type.
		 */
		k = ieee80211_crypto_encap(ni, m0);
		if (k == NULL) {
			/*
			 * This can happen when the key is yanked after the
			 * frame was queued.  Just discard the frame; the
			 * 802.11 layer counts failures and provides
			 * debugging/diagnostics.
			 */
			ath_freetx(m0);
			return EIO;
		}
		/*
		 * Adjust the packet + header lengths for the crypto
		 * additions and calculate the h/w key index.  When
		 * a s/w mic is done the frame will have had any mic
		 * added to it prior to entry so m0->m_pkthdr.len will
		 * account for it. Otherwise we need to add it to the
		 * packet length.
		 */
		cip = k->wk_cipher;
		hdrlen += cip->ic_header;
		pktlen += cip->ic_header + cip->ic_trailer;
		/* NB: frags always have any TKIP MIC done in s/w */
		if ((k->wk_flags & IEEE80211_KEY_SWMIC) == 0 && !isfrag)
			pktlen += cip->ic_miclen;
		keyix = k->wk_keyix;

		/* packet header may have moved, reset our local pointer */
		wh = mtod(m0, struct ieee80211_frame *);
	} else if (ni->ni_ucastkey.wk_cipher == &ieee80211_cipher_none) {
		/*
		 * Use station key cache slot, if assigned.
		 */
		keyix = ni->ni_ucastkey.wk_keyix;
		if (keyix == IEEE80211_KEYIX_NONE)
			keyix = HAL_TXKEYIX_INVALID;
	} else
		keyix = HAL_TXKEYIX_INVALID;

	pktlen += IEEE80211_CRC_LEN;

	/*
	 * Load the DMA map so any coalescing is done.  This
	 * also calculates the number of descriptors we need.
	 */
	error = ath_tx_dmasetup(sc, bf, m0);
	if (error != 0)
		return error;
	bf->bf_node = ni;			/* NB: held reference */
	m0 = bf->bf_m;				/* NB: may have changed */
	wh = mtod(m0, struct ieee80211_frame *);

	/* setup descriptors */
	ds = bf->bf_desc;
	rt = sc->sc_currates;
	KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode));

	/*
	 * NB: the 802.11 layer marks whether or not we should
	 * use short preamble based on the current mode and
	 * negotiated parameters.
	 */
	if ((ic->ic_flags & IEEE80211_F_SHPREAMBLE) &&
	    (ni->ni_capinfo & IEEE80211_CAPINFO_SHORT_PREAMBLE)) {
		shortPreamble = AH_TRUE;
		sc->sc_stats.ast_tx_shortpre++;
	} else {
		shortPreamble = AH_FALSE;
	}

	an = ATH_NODE(ni);
	flags = HAL_TXDESC_CLRDMASK;		/* XXX needed for crypto errs */
	ismrr = 0;				/* default no multi-rate retry*/
	pri = M_WME_GETAC(m0);			/* honor classification */
	/* XXX use txparams instead of fixed values */
	/*
	 * Calculate Atheros packet type from IEEE80211 packet header,
	 * setup for rate calculations, and select h/w transmit queue.
	 */
	switch (wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) {
	case IEEE80211_FC0_TYPE_MGT:
		subtype = wh->i_fc[0] & IEEE80211_FC0_SUBTYPE_MASK;
		if (subtype == IEEE80211_FC0_SUBTYPE_BEACON)
			atype = HAL_PKT_TYPE_BEACON;
		else if (subtype == IEEE80211_FC0_SUBTYPE_PROBE_RESP)
			atype = HAL_PKT_TYPE_PROBE_RESP;
		else if (subtype == IEEE80211_FC0_SUBTYPE_ATIM)
			atype = HAL_PKT_TYPE_ATIM;
		else
			atype = HAL_PKT_TYPE_NORMAL;	/* XXX */
		rix = an->an_mgmtrix;
		txrate = rt->info[rix].rateCode;
		if (shortPreamble)
			txrate |= rt->info[rix].shortPreamble;
		try0 = ATH_TXMGTTRY;
		flags |= HAL_TXDESC_INTREQ;	/* force interrupt */
		break;
	case IEEE80211_FC0_TYPE_CTL:
		atype = HAL_PKT_TYPE_PSPOLL;	/* stop setting of duration */
		rix = an->an_mgmtrix;
		txrate = rt->info[rix].rateCode;
		if (shortPreamble)
			txrate |= rt->info[rix].shortPreamble;
		try0 = ATH_TXMGTTRY;
		flags |= HAL_TXDESC_INTREQ;	/* force interrupt */
		break;
	case IEEE80211_FC0_TYPE_DATA:
		atype = HAL_PKT_TYPE_NORMAL;		/* default */
		/*
		 * Data frames: multicast frames go out at a fixed rate,
		 * EAPOL frames use the mgmt frame rate; otherwise consult
		 * the rate control module for the rate to use.
		 */
		if (ismcast) {
			rix = an->an_mcastrix;
			txrate = rt->info[rix].rateCode;
			if (shortPreamble)
				txrate |= rt->info[rix].shortPreamble;
			try0 = 1;
		} else if (m0->m_flags & M_EAPOL) {
			/* XXX? maybe always use long preamble? */
			rix = an->an_mgmtrix;
			txrate = rt->info[rix].rateCode;
			if (shortPreamble)
				txrate |= rt->info[rix].shortPreamble;
			try0 = ATH_TXMAXTRY;	/* XXX?too many? */
		} else {
			ath_rate_findrate(sc, an, shortPreamble, pktlen,
				&rix, &try0, &txrate);
			sc->sc_txrix = rix;		/* for LED blinking */
			sc->sc_lastdatarix = rix;	/* for fast frames */
			if (try0 != ATH_TXMAXTRY)
				ismrr = 1;
		}
		if (cap->cap_wmeParams[pri].wmep_noackPolicy)
			flags |= HAL_TXDESC_NOACK;
		break;
	default:
		if_printf(ifp, "bogus frame type 0x%x (%s)\n",
			wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK, __func__);
		/* XXX statistic */
		ath_freetx(m0);
		return EIO;
	}
	txq = sc->sc_ac2q[pri];

	/*
	 * When servicing one or more stations in power-save mode
	 * (or) if there is some mcast data waiting on the mcast
	 * queue (to prevent out of order delivery) multicast
	 * frames must be buffered until after the beacon.
	 */
	if (ismcast && (vap->iv_ps_sta || avp->av_mcastq.axq_depth))
		txq = &avp->av_mcastq;

	/*
	 * Calculate miscellaneous flags.
	 */
	if (ismcast) {
		flags |= HAL_TXDESC_NOACK;	/* no ack on broad/multicast */
	} else if (pktlen > vap->iv_rtsthreshold &&
	    (ni->ni_ath_flags & IEEE80211_NODE_FF) == 0) {
		flags |= HAL_TXDESC_RTSENA;	/* RTS based on frame length */
		cix = rt->info[rix].controlRate;
		sc->sc_stats.ast_tx_rts++;
	}
	if (flags & HAL_TXDESC_NOACK)		/* NB: avoid double counting */
		sc->sc_stats.ast_tx_noack++;
#ifdef IEEE80211_SUPPORT_TDMA
	if (sc->sc_tdma && (flags & HAL_TXDESC_NOACK) == 0) {
		DPRINTF(sc, ATH_DEBUG_TDMA,
		    "%s: discard frame, ACK required w/ TDMA\n", __func__);
		sc->sc_stats.ast_tdma_ack++;
		ath_freetx(m0);
		return EIO;
	}
#endif

	/*
	 * If 802.11g protection is enabled, determine whether
	 * to use RTS/CTS or just CTS.  Note that this is only
	 * done for OFDM unicast frames.
	 */
	if ((ic->ic_flags & IEEE80211_F_USEPROT) &&
	    rt->info[rix].phy == IEEE80211_T_OFDM &&
	    (flags & HAL_TXDESC_NOACK) == 0) {
		/* XXX fragments must use CCK rates w/ protection */
		if (ic->ic_protmode == IEEE80211_PROT_RTSCTS)
			flags |= HAL_TXDESC_RTSENA;
		else if (ic->ic_protmode == IEEE80211_PROT_CTSONLY)
			flags |= HAL_TXDESC_CTSENA;
		if (isfrag) {
			/*
			 * For frags it would be desirable to use the
			 * highest CCK rate for RTS/CTS.  But stations
			 * farther away may detect it at a lower CCK rate
			 * so use the configured protection rate instead
			 * (for now).
			 */
			cix = rt->info[sc->sc_protrix].controlRate;
		} else
			cix = rt->info[sc->sc_protrix].controlRate;
		sc->sc_stats.ast_tx_protect++;
	}

	/*
	 * Calculate duration.  This logically belongs in the 802.11
	 * layer but it lacks sufficient information to calculate it.
	 */
	if ((flags & HAL_TXDESC_NOACK) == 0 &&
	    (wh->i_fc[0] & IEEE80211_FC0_TYPE_MASK) != IEEE80211_FC0_TYPE_CTL) {
		u_int16_t dur;
		if (shortPreamble)
			dur = rt->info[rix].spAckDuration;
		else
			dur = rt->info[rix].lpAckDuration;
		if (wh->i_fc[1] & IEEE80211_FC1_MORE_FRAG) {
			dur += dur;		/* additional SIFS+ACK */
			KASSERT(m0->m_nextpkt != NULL, ("no fragment"));
			/*
			 * Include the size of next fragment so NAV is
			 * updated properly.  The last fragment uses only
			 * the ACK duration
			 */
			dur += ath_hal_computetxtime(ah, rt,
					m0->m_nextpkt->m_pkthdr.len,
					rix, shortPreamble);
		}
		if (isfrag) {
			/*
			 * Force hardware to use computed duration for next
			 * fragment by disabling multi-rate retry which updates
			 * duration based on the multi-rate duration table.
			 */
			ismrr = 0;
			try0 = ATH_TXMGTTRY;	/* XXX? */
		}
		*(u_int16_t *)wh->i_dur = htole16(dur);
	}

	/*
	 * Calculate RTS/CTS rate and duration if needed.
	 */
	ctsduration = 0;
	if (flags & (HAL_TXDESC_RTSENA|HAL_TXDESC_CTSENA)) {
		/*
		 * CTS transmit rate is derived from the transmit rate
		 * by looking in the h/w rate table.  We must also factor
		 * in whether or not a short preamble is to be used.
		 */
		/* NB: cix is set above where RTS/CTS is enabled */
		KASSERT(cix != 0xff, ("cix not setup"));
		ctsrate = rt->info[cix].rateCode;
		/*
		 * Compute the transmit duration based on the frame
		 * size and the size of an ACK frame.  We call into the
		 * HAL to do the computation since it depends on the
		 * characteristics of the actual PHY being used.
		 *
		 * NB: CTS is assumed the same size as an ACK so we can
		 *     use the precalculated ACK durations.
		 */
		if (shortPreamble) {
			ctsrate |= rt->info[cix].shortPreamble;
			if (flags & HAL_TXDESC_RTSENA)		/* SIFS + CTS */
				ctsduration += rt->info[cix].spAckDuration;
			ctsduration += ath_hal_computetxtime(ah,
				rt, pktlen, rix, AH_TRUE);
			if ((flags & HAL_TXDESC_NOACK) == 0)	/* SIFS + ACK */
				ctsduration += rt->info[rix].spAckDuration;
		} else {
			if (flags & HAL_TXDESC_RTSENA)		/* SIFS + CTS */
				ctsduration += rt->info[cix].lpAckDuration;
			ctsduration += ath_hal_computetxtime(ah,
				rt, pktlen, rix, AH_FALSE);
			if ((flags & HAL_TXDESC_NOACK) == 0)	/* SIFS + ACK */
				ctsduration += rt->info[rix].lpAckDuration;
		}
		/*
		 * Must disable multi-rate retry when using RTS/CTS.
		 */
		ismrr = 0;
		try0 = ATH_TXMGTTRY;		/* XXX */
	} else
		ctsrate = 0;

	/*
	 * At this point we are committed to sending the frame
	 * and we don't need to look at m_nextpkt; clear it in
	 * case this frame is part of frag chain.
	 */
	m0->m_nextpkt = NULL;

	if (IFF_DUMPPKTS(sc, ATH_DEBUG_XMIT))
		ieee80211_dump_pkt(ic, mtod(m0, caddr_t), m0->m_len,
			sc->sc_hwmap[rix].ieeerate, -1);

	if (bpf_peers_present(ifp->if_bpf)) {
		u_int64_t tsf = ath_hal_gettsf64(ah);

		sc->sc_tx_th.wt_tsf = htole64(tsf);
		sc->sc_tx_th.wt_flags = sc->sc_hwmap[rix].txflags;
		if (iswep)
			sc->sc_tx_th.wt_flags |= IEEE80211_RADIOTAP_F_WEP;
		if (isfrag)
			sc->sc_tx_th.wt_flags |= IEEE80211_RADIOTAP_F_FRAG;
		sc->sc_tx_th.wt_rate = sc->sc_hwmap[rix].ieeerate;
		sc->sc_tx_th.wt_txpower = ni->ni_txpower;
		sc->sc_tx_th.wt_antenna = sc->sc_txantenna;

		bpf_mtap2(ifp->if_bpf, &sc->sc_tx_th, sc->sc_tx_th_len, m0);
	}

	/*
	 * Determine if a tx interrupt should be generated for
	 * this descriptor.  We take a tx interrupt to reap
	 * descriptors when the h/w hits an EOL condition or
	 * when the descriptor is specifically marked to generate
	 * an interrupt.  We periodically mark descriptors in this
	 * way to insure timely replenishing of the supply needed
	 * for sending frames.  Defering interrupts reduces system
	 * load and potentially allows more concurrent work to be
	 * done but if done to aggressively can cause senders to
	 * backup.
	 *
	 * NB: use >= to deal with sc_txintrperiod changing
	 *     dynamically through sysctl.
	 */
	if (flags & HAL_TXDESC_INTREQ) {
		txq->axq_intrcnt = 0;
	} else if (++txq->axq_intrcnt >= sc->sc_txintrperiod) {
		flags |= HAL_TXDESC_INTREQ;
		txq->axq_intrcnt = 0;
	}

	/*
	 * Formulate first tx descriptor with tx controls.
	 */
	/* XXX check return value? */
	ath_hal_setuptxdesc(ah, ds
		, pktlen		/* packet length */
		, hdrlen		/* header length */
		, atype			/* Atheros packet type */
		, ni->ni_txpower	/* txpower */
		, txrate, try0		/* series 0 rate/tries */
		, keyix			/* key cache index */
		, sc->sc_txantenna	/* antenna mode */
		, flags			/* flags */
		, ctsrate		/* rts/cts rate */
		, ctsduration		/* rts/cts duration */
	);
	bf->bf_txflags = flags;
	/*
	 * Setup the multi-rate retry state only when we're
	 * going to use it.  This assumes ath_hal_setuptxdesc
	 * initializes the descriptors (so we don't have to)
	 * when the hardware supports multi-rate retry and
	 * we don't use it.
	 */
	if (ismrr)
		ath_rate_setupxtxdesc(sc, an, ds, shortPreamble, rix);

	ath_tx_handoff(sc, txq, bf);
	return 0;
}

/*
 * Process completed xmit descriptors from the specified queue.
 */
static int
ath_tx_processq(struct ath_softc *sc, struct ath_txq *txq)
{
	struct ath_hal *ah = sc->sc_ah;
	struct ifnet *ifp = sc->sc_ifp;
	struct ieee80211com *ic = ifp->if_l2com;
	struct ath_buf *bf, *last;
	struct ath_desc *ds, *ds0;
	struct ath_tx_status *ts;
	struct ieee80211_node *ni;
	struct ath_node *an;
	int sr, lr, pri, nacked;
	HAL_STATUS status;

	DPRINTF(sc, ATH_DEBUG_TX_PROC, "%s: tx queue %u head %p link %p\n",
		__func__, txq->axq_qnum,
		(caddr_t)(uintptr_t) ath_hal_gettxbuf(sc->sc_ah, txq->axq_qnum),
		txq->axq_link);
	nacked = 0;
	for (;;) {
		ATH_TXQ_LOCK(txq);
		txq->axq_intrcnt = 0;	/* reset periodic desc intr count */
		bf = STAILQ_FIRST(&txq->axq_q);
		if (bf == NULL) {
			ATH_TXQ_UNLOCK(txq);
			break;
		}
		ds0 = &bf->bf_desc[0];
		ds = &bf->bf_desc[bf->bf_nseg - 1];
		ts = &bf->bf_status.ds_txstat;
		status = ath_hal_txprocdesc(ah, ds, ts);
#ifdef ATH_DEBUG
		if (sc->sc_debug & ATH_DEBUG_XMIT_DESC)
			ath_printtxbuf(sc, bf, txq->axq_qnum, 0,
			    status == HAL_OK);
#endif
		if (status == HAL_EINPROGRESS) {
			ATH_TXQ_UNLOCK(txq);
			break;
		}
		ATH_TXQ_REMOVE_HEAD(txq, bf_list);
#ifdef IEEE80211_SUPPORT_TDMA
		if (txq->axq_depth > 0) {
			/*
			 * More frames follow.  Mark the buffer busy
			 * so it's not re-used while the hardware may
			 * still re-read the link field in the descriptor.
			 */
			bf->bf_flags |= ATH_BUF_BUSY;
		} else
#else
		if (txq->axq_depth == 0)
#endif
			txq->axq_link = NULL;
		ATH_TXQ_UNLOCK(txq);

		ni = bf->bf_node;
		if (ni != NULL) {
			an = ATH_NODE(ni);
			if (ts->ts_status == 0) {
				u_int8_t txant = ts->ts_antenna;
				sc->sc_stats.ast_ant_tx[txant]++;
				sc->sc_ant_tx[txant]++;
				if (ts->ts_rate & HAL_TXSTAT_ALTRATE)
					sc->sc_stats.ast_tx_altrate++;
				pri = M_WME_GETAC(bf->bf_m);
				if (pri >= WME_AC_VO)
					ic->ic_wme.wme_hipri_traffic++;
				if ((bf->bf_txflags & HAL_TXDESC_NOACK) == 0)
					ni->ni_inact = ni->ni_inact_reload;
			} else {
				if (ts->ts_status & HAL_TXERR_XRETRY)
					sc->sc_stats.ast_tx_xretries++;
				if (ts->ts_status & HAL_TXERR_FIFO)
					sc->sc_stats.ast_tx_fifoerr++;
				if (ts->ts_status & HAL_TXERR_FILT)
					sc->sc_stats.ast_tx_filtered++;
				if (bf->bf_m->m_flags & M_FF)
					sc->sc_stats.ast_ff_txerr++;
			}
			sr = ts->ts_shortretry;
			lr = ts->ts_longretry;
			sc->sc_stats.ast_tx_shortretry += sr;
			sc->sc_stats.ast_tx_longretry += lr;
			/*
			 * Hand the descriptor to the rate control algorithm.
			 */
			if ((ts->ts_status & HAL_TXERR_FILT) == 0 &&
			    (bf->bf_txflags & HAL_TXDESC_NOACK) == 0) {
				/*
				 * If frame was ack'd update statistics,
				 * including the last rx time used to
				 * workaround phantom bmiss interrupts.
				 */
				if (ts->ts_status == 0) {
					nacked++;
					sc->sc_stats.ast_tx_rssi = ts->ts_rssi;
					ATH_RSSI_LPF(sc->sc_halstats.ns_avgtxrssi,
						ts->ts_rssi);
				}
				ath_rate_tx_complete(sc, an, bf);
			}
			/*
			 * Do any tx complete callback.  Note this must
			 * be done before releasing the node reference.
			 */
			if (bf->bf_m->m_flags & M_TXCB)
				ieee80211_process_callback(ni, bf->bf_m,
				    (bf->bf_txflags & HAL_TXDESC_NOACK) == 0 ?
				        ts->ts_status : HAL_TXERR_XRETRY);
			/*
			 * Reclaim reference to node.
			 *
			 * NB: the node may be reclaimed here if, for example
			 *     this is a DEAUTH message that was sent and the
			 *     node was timed out due to inactivity.
			 */
			ieee80211_free_node(ni);
		}
		bus_dmamap_sync(sc->sc_dmat, bf->bf_dmamap,
		    BUS_DMASYNC_POSTWRITE);
		bus_dmamap_unload(sc->sc_dmat, bf->bf_dmamap);

		m_freem(bf->bf_m);
		bf->bf_m = NULL;
		bf->bf_node = NULL;

		ATH_TXBUF_LOCK(sc);
		last = STAILQ_LAST(&sc->sc_txbuf, ath_buf, bf_list);
		if (last != NULL)
			last->bf_flags &= ~ATH_BUF_BUSY;
		STAILQ_INSERT_TAIL(&sc->sc_txbuf, bf, bf_list);
		ATH_TXBUF_UNLOCK(sc);
	}
	/*
	 * Flush fast-frame staging queue when traffic slows.
	 */
	if (txq->axq_depth <= 1)
		ath_ff_stageq_flush(sc, txq, ath_ff_always);
	return nacked;
}

static __inline int
txqactive(struct ath_hal *ah, int qnum)
{
	u_int32_t txqs = 1<<qnum;
	ath_hal_gettxintrtxqs(ah, &txqs);
	return (txqs & (1<<qnum));
}

/*
 * Deferred processing of transmit interrupt; special-cased
 * for a single hardware transmit queue (e.g. 5210 and 5211).
 */
static void
ath_tx_proc_q0(void *arg, int npending)
{
	struct ath_softc *sc = arg;
	struct ifnet *ifp = sc->sc_ifp;

	if (txqactive(sc->sc_ah, 0) && ath_tx_processq(sc, &sc->sc_txq[0]))
		sc->sc_lastrx = ath_hal_gettsf64(sc->sc_ah);
	if (txqactive(sc->sc_ah, sc->sc_cabq->axq_qnum))
		ath_tx_processq(sc, sc->sc_cabq);
	ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
	sc->sc_wd_timer = 0;

	if (sc->sc_softled)
		ath_led_event(sc, sc->sc_txrix);

	ath_start(ifp);
}

/*
 * Deferred processing of transmit interrupt; special-cased
 * for four hardware queues, 0-3 (e.g. 5212 w/ WME support).
 */
static void
ath_tx_proc_q0123(void *arg, int npending)
{
	struct ath_softc *sc = arg;
	struct ifnet *ifp = sc->sc_ifp;
	int nacked;

	/*
	 * Process each active queue.
	 */
	nacked = 0;
	if (txqactive(sc->sc_ah, 0))
		nacked += ath_tx_processq(sc, &sc->sc_txq[0]);
	if (txqactive(sc->sc_ah, 1))
		nacked += ath_tx_processq(sc, &sc->sc_txq[1]);
	if (txqactive(sc->sc_ah, 2))
		nacked += ath_tx_processq(sc, &sc->sc_txq[2]);
	if (txqactive(sc->sc_ah, 3))
		nacked += ath_tx_processq(sc, &sc->sc_txq[3]);
	if (txqactive(sc->sc_ah, sc->sc_cabq->axq_qnum))
		ath_tx_processq(sc, sc->sc_cabq);
	if (nacked)
		sc->sc_lastrx = ath_hal_gettsf64(sc->sc_ah);

	ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
	sc->sc_wd_timer = 0;

	if (sc->sc_softled)
		ath_led_event(sc, sc->sc_txrix);

	ath_start(ifp);
}

/*
 * Deferred processing of transmit interrupt.
 */
static void
ath_tx_proc(void *arg, int npending)
{
	struct ath_softc *sc = arg;
	struct ifnet *ifp = sc->sc_ifp;
	int i, nacked;

	/*
	 * Process each active queue.
	 */
	nacked = 0;
	for (i = 0; i < HAL_NUM_TX_QUEUES; i++)
		if (ATH_TXQ_SETUP(sc, i) && txqactive(sc->sc_ah, i))
			nacked += ath_tx_processq(sc, &sc->sc_txq[i]);
	if (nacked)
		sc->sc_lastrx = ath_hal_gettsf64(sc->sc_ah);

	ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
	sc->sc_wd_timer = 0;

	if (sc->sc_softled)
		ath_led_event(sc, sc->sc_txrix);

	ath_start(ifp);
}

static void
ath_tx_draintxq(struct ath_softc *sc, struct ath_txq *txq)
{
#ifdef ATH_DEBUG
	struct ath_hal *ah = sc->sc_ah;
#endif
	struct ieee80211_node *ni;
	struct ath_buf *bf;
	u_int ix;

	/*
	 * NB: this assumes output has been stopped and
	 *     we do not need to block ath_tx_proc
	 */
	ATH_TXBUF_LOCK(sc);
	bf = STAILQ_LAST(&sc->sc_txbuf, ath_buf, bf_list);
	if (bf != NULL)
		bf->bf_flags &= ~ATH_BUF_BUSY;
	ATH_TXBUF_UNLOCK(sc);
	for (ix = 0;; ix++) {
		ATH_TXQ_LOCK(txq);
		bf = STAILQ_FIRST(&txq->axq_q);
		if (bf == NULL) {
			txq->axq_link = NULL;
			ATH_TXQ_UNLOCK(txq);
			break;
		}
		ATH_TXQ_REMOVE_HEAD(txq, bf_list);
		ATH_TXQ_UNLOCK(txq);
#ifdef ATH_DEBUG
		if (sc->sc_debug & ATH_DEBUG_RESET) {
			struct ieee80211com *ic = sc->sc_ifp->if_l2com;

			ath_printtxbuf(sc, bf, txq->axq_qnum, ix,
				ath_hal_txprocdesc(ah, bf->bf_desc,
				    &bf->bf_status.ds_txstat) == HAL_OK);
			ieee80211_dump_pkt(ic, mtod(bf->bf_m, caddr_t),
				bf->bf_m->m_len, 0, -1);
		}
#endif /* ATH_DEBUG */
		bus_dmamap_unload(sc->sc_dmat, bf->bf_dmamap);
		ni = bf->bf_node;
		bf->bf_node = NULL;
		if (ni != NULL) {
			/*
			 * Do any callback and reclaim the node reference.
			 */
			if (bf->bf_m->m_flags & M_TXCB)
				ieee80211_process_callback(ni, bf->bf_m, -1);
			ieee80211_free_node(ni);
		}
		m_freem(bf->bf_m);
		bf->bf_m = NULL;
		bf->bf_flags &= ~ATH_BUF_BUSY;

		ATH_TXBUF_LOCK(sc);
		STAILQ_INSERT_TAIL(&sc->sc_txbuf, bf, bf_list);
		ATH_TXBUF_UNLOCK(sc);
	}
}

static void
ath_tx_stopdma(struct ath_softc *sc, struct ath_txq *txq)
{
	struct ath_hal *ah = sc->sc_ah;

	DPRINTF(sc, ATH_DEBUG_RESET, "%s: tx queue [%u] %p, link %p\n",
	    __func__, txq->axq_qnum,
	    (caddr_t)(uintptr_t) ath_hal_gettxbuf(ah, txq->axq_qnum),
	    txq->axq_link);
	(void) ath_hal_stoptxdma(ah, txq->axq_qnum);
}

/*
 * Drain the transmit queues and reclaim resources.
 */
static void
ath_draintxq(struct ath_softc *sc)
{
	struct ath_hal *ah = sc->sc_ah;
	struct ifnet *ifp = sc->sc_ifp;
	int i;

	/* XXX return value */
	if (!sc->sc_invalid) {
		/* don't touch the hardware if marked invalid */
		DPRINTF(sc, ATH_DEBUG_RESET, "%s: tx queue [%u] %p, link %p\n",
		    __func__, sc->sc_bhalq,
		    (caddr_t)(uintptr_t) ath_hal_gettxbuf(ah, sc->sc_bhalq),
		    NULL);
		(void) ath_hal_stoptxdma(ah, sc->sc_bhalq);
		for (i = 0; i < HAL_NUM_TX_QUEUES; i++)
			if (ATH_TXQ_SETUP(sc, i))
				ath_tx_stopdma(sc, &sc->sc_txq[i]);
	}
	for (i = 0; i < HAL_NUM_TX_QUEUES; i++)
		if (ATH_TXQ_SETUP(sc, i))
			ath_tx_draintxq(sc, &sc->sc_txq[i]);
#ifdef ATH_DEBUG
	if (sc->sc_debug & ATH_DEBUG_RESET) {
		struct ath_buf *bf = STAILQ_FIRST(&sc->sc_bbuf);
		if (bf != NULL && bf->bf_m != NULL) {
			ath_printtxbuf(sc, bf, sc->sc_bhalq, 0,
				ath_hal_txprocdesc(ah, bf->bf_desc,
				    &bf->bf_status.ds_txstat) == HAL_OK);
			ieee80211_dump_pkt(ifp->if_l2com, mtod(bf->bf_m, caddr_t),
				bf->bf_m->m_len, 0, -1);
		}
	}
#endif /* ATH_DEBUG */
	ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
	sc->sc_wd_timer = 0;
}

/*
 * Disable the receive h/w in preparation for a reset.
 */
static void
ath_stoprecv(struct ath_softc *sc)
{
#define	PA2DESC(_sc, _pa) \
	((struct ath_desc *)((caddr_t)(_sc)->sc_rxdma.dd_desc + \
		((_pa) - (_sc)->sc_rxdma.dd_desc_paddr)))
	struct ath_hal *ah = sc->sc_ah;

	ath_hal_stoppcurecv(ah);	/* disable PCU */
	ath_hal_setrxfilter(ah, 0);	/* clear recv filter */
	ath_hal_stopdmarecv(ah);	/* disable DMA engine */
	DELAY(3000);			/* 3ms is long enough for 1 frame */
#ifdef ATH_DEBUG
	if (sc->sc_debug & (ATH_DEBUG_RESET | ATH_DEBUG_FATAL)) {
		struct ath_buf *bf;
		u_int ix;

		printf("%s: rx queue %p, link %p\n", __func__,
			(caddr_t)(uintptr_t) ath_hal_getrxbuf(ah), sc->sc_rxlink);
		ix = 0;
		STAILQ_FOREACH(bf, &sc->sc_rxbuf, bf_list) {
			struct ath_desc *ds = bf->bf_desc;
			struct ath_rx_status *rs = &bf->bf_status.ds_rxstat;
			HAL_STATUS status = ath_hal_rxprocdesc(ah, ds,
				bf->bf_daddr, PA2DESC(sc, ds->ds_link), rs);
			if (status == HAL_OK || (sc->sc_debug & ATH_DEBUG_FATAL))
				ath_printrxbuf(sc, bf, ix, status == HAL_OK);
			ix++;
		}
	}
#endif
	if (sc->sc_rxpending != NULL) {
		m_freem(sc->sc_rxpending);
		sc->sc_rxpending = NULL;
	}
	sc->sc_rxlink = NULL;		/* just in case */
#undef PA2DESC
}

/*
 * Enable the receive h/w following a reset.
 */
static int
ath_startrecv(struct ath_softc *sc)
{
	struct ath_hal *ah = sc->sc_ah;
	struct ath_buf *bf;

	sc->sc_rxlink = NULL;
	sc->sc_rxpending = NULL;
	STAILQ_FOREACH(bf, &sc->sc_rxbuf, bf_list) {
		int error = ath_rxbuf_init(sc, bf);
		if (error != 0) {
			DPRINTF(sc, ATH_DEBUG_RECV,
				"%s: ath_rxbuf_init failed %d\n",
				__func__, error);
			return error;
		}
	}

	bf = STAILQ_FIRST(&sc->sc_rxbuf);
	ath_hal_putrxbuf(ah, bf->bf_daddr);
	ath_hal_rxena(ah);		/* enable recv descriptors */
	ath_mode_init(sc);		/* set filters, etc. */
	ath_hal_startpcurecv(ah);	/* re-enable PCU/DMA engine */
	return 0;
}

/*
 * Update internal state after a channel change.
 */
static void
ath_chan_change(struct ath_softc *sc, struct ieee80211_channel *chan)
{
	enum ieee80211_phymode mode;

	/*
	 * Change channels and update the h/w rate map
	 * if we're switching; e.g. 11a to 11b/g.
	 */
	mode = ieee80211_chan2mode(chan);
	if (mode != sc->sc_curmode)
		ath_setcurmode(sc, mode);
	sc->sc_curchan = chan;

	sc->sc_rx_th.wr_chan_flags = htole32(chan->ic_flags);
	sc->sc_tx_th.wt_chan_flags = sc->sc_rx_th.wr_chan_flags;
	sc->sc_rx_th.wr_chan_freq = htole16(chan->ic_freq);
	sc->sc_tx_th.wt_chan_freq = sc->sc_rx_th.wr_chan_freq;
	sc->sc_rx_th.wr_chan_ieee = chan->ic_ieee;
	sc->sc_tx_th.wt_chan_ieee = sc->sc_rx_th.wr_chan_ieee;
	sc->sc_rx_th.wr_chan_maxpow = chan->ic_maxregpower;
	sc->sc_tx_th.wt_chan_maxpow = sc->sc_rx_th.wr_chan_maxpow;
}

/*
 * Set/change channels.  If the channel is really being changed,
 * it's done by reseting the chip.  To accomplish this we must
 * first cleanup any pending DMA, then restart stuff after a la
 * ath_init.
 */
static int
ath_chan_set(struct ath_softc *sc, struct ieee80211_channel *chan)
{
	struct ifnet *ifp = sc->sc_ifp;
	struct ieee80211com *ic = ifp->if_l2com;
	struct ath_hal *ah = sc->sc_ah;

	DPRINTF(sc, ATH_DEBUG_RESET, "%s: %u (%u MHz, flags 0x%x)\n",
	    __func__, ieee80211_chan2ieee(ic, chan),
	    chan->ic_freq, chan->ic_flags);
	if (chan != sc->sc_curchan) {
		HAL_STATUS status;
		/*
		 * To switch channels clear any pending DMA operations;
		 * wait long enough for the RX fifo to drain, reset the
		 * hardware at the new frequency, and then re-enable
		 * the relevant bits of the h/w.
		 */
		ath_hal_intrset(ah, 0);		/* disable interrupts */
		ath_draintxq(sc);		/* clear pending tx frames */
		ath_stoprecv(sc);		/* turn off frame recv */
		if (!ath_hal_reset(ah, sc->sc_opmode, chan, AH_TRUE, &status)) {
			if_printf(ifp, "%s: unable to reset "
			    "channel %u (%u Mhz, flags 0x%x), hal status %u\n",
			    __func__, ieee80211_chan2ieee(ic, chan),
			    chan->ic_freq, chan->ic_flags, status);
			return EIO;
		}
		sc->sc_diversity = ath_hal_getdiversity(ah);

		/*
		 * Re-enable rx framework.
		 */
		if (ath_startrecv(sc) != 0) {
			if_printf(ifp, "%s: unable to restart recv logic\n",
			    __func__);
			return EIO;
		}

		/*
		 * Change channels and update the h/w rate map
		 * if we're switching; e.g. 11a to 11b/g.
		 */
		ath_chan_change(sc, chan);

		/*
		 * Re-enable interrupts.
		 */
		ath_hal_intrset(ah, sc->sc_imask);
	}
	return 0;
}

/*
 * Periodically recalibrate the PHY to account
 * for temperature/environment changes.
 */
static void
ath_calibrate(void *arg)
{
	struct ath_softc *sc = arg;
	struct ath_hal *ah = sc->sc_ah;
	struct ifnet *ifp = sc->sc_ifp;
	struct ieee80211com *ic = ifp->if_l2com;
	HAL_BOOL longCal, isCalDone;
	int nextcal;

	if (ic->ic_flags & IEEE80211_F_SCAN)	/* defer, off channel */
		goto restart;
	longCal = (ticks - sc->sc_lastlongcal >= ath_longcalinterval*hz);
	if (longCal) {
		sc->sc_stats.ast_per_cal++;
		if (ath_hal_getrfgain(ah) == HAL_RFGAIN_NEED_CHANGE) {
			/*
			 * Rfgain is out of bounds, reset the chip
			 * to load new gain values.
			 */
			DPRINTF(sc, ATH_DEBUG_CALIBRATE,
				"%s: rfgain change\n", __func__);
			sc->sc_stats.ast_per_rfgain++;
			ath_reset(ifp);
		}
		/*
		 * If this long cal is after an idle period, then
		 * reset the data collection state so we start fresh.
		 */
		if (sc->sc_resetcal) {
			(void) ath_hal_calreset(ah, sc->sc_curchan);
			sc->sc_lastcalreset = ticks;
			sc->sc_resetcal = 0;
		}
	}
	if (ath_hal_calibrateN(ah, sc->sc_curchan, longCal, &isCalDone)) {
		if (longCal) {
			/*
			 * Calibrate noise floor data again in case of change.
			 */
			ath_hal_process_noisefloor(ah);
		}
	} else {
		DPRINTF(sc, ATH_DEBUG_ANY,
			"%s: calibration of channel %u failed\n",
			__func__, sc->sc_curchan->ic_freq);
		sc->sc_stats.ast_per_calfail++;
	}
	if (!isCalDone) {
restart:
		/*
		 * Use a shorter interval to potentially collect multiple
		 * data samples required to complete calibration.  Once
		 * we're told the work is done we drop back to a longer
		 * interval between requests.  We're more aggressive doing
		 * work when operating as an AP to improve operation right
		 * after startup.
		 */
		nextcal = (1000*ath_shortcalinterval)/hz;
		if (sc->sc_opmode != HAL_M_HOSTAP)
			nextcal *= 10;
	} else {
		nextcal = ath_longcalinterval*hz;
		sc->sc_lastlongcal = ticks;
		if (sc->sc_lastcalreset == 0)
			sc->sc_lastcalreset = sc->sc_lastlongcal;
		else if (ticks - sc->sc_lastcalreset >= ath_resetcalinterval*hz)
			sc->sc_resetcal = 1;	/* setup reset next trip */
	}

	if (nextcal != 0) {
		DPRINTF(sc, ATH_DEBUG_CALIBRATE, "%s: next +%u (%sisCalDone)\n",
		    __func__, nextcal, isCalDone ? "" : "!");
		callout_reset(&sc->sc_cal_ch, nextcal, ath_calibrate, sc);
	} else {
		DPRINTF(sc, ATH_DEBUG_CALIBRATE, "%s: calibration disabled\n",
		    __func__);
		/* NB: don't rearm timer */
	}
}

static void
ath_scan_start(struct ieee80211com *ic)
{
	struct ifnet *ifp = ic->ic_ifp;
	struct ath_softc *sc = ifp->if_softc;
	struct ath_hal *ah = sc->sc_ah;
	u_int32_t rfilt;

	/* XXX calibration timer? */

	sc->sc_scanning = 1;
	sc->sc_syncbeacon = 0;
	rfilt = ath_calcrxfilter(sc);
	ath_hal_setrxfilter(ah, rfilt);
	ath_hal_setassocid(ah, ifp->if_broadcastaddr, 0);

	DPRINTF(sc, ATH_DEBUG_STATE, "%s: RX filter 0x%x bssid %s aid 0\n",
		 __func__, rfilt, ether_sprintf(ifp->if_broadcastaddr));
}

static void
ath_scan_end(struct ieee80211com *ic)
{
	struct ifnet *ifp = ic->ic_ifp;
	struct ath_softc *sc = ifp->if_softc;
	struct ath_hal *ah = sc->sc_ah;
	u_int32_t rfilt;

	sc->sc_scanning = 0;
	rfilt = ath_calcrxfilter(sc);
	ath_hal_setrxfilter(ah, rfilt);
	ath_hal_setassocid(ah, sc->sc_curbssid, sc->sc_curaid);

	ath_hal_process_noisefloor(ah);

	DPRINTF(sc, ATH_DEBUG_STATE, "%s: RX filter 0x%x bssid %s aid 0x%x\n",
		 __func__, rfilt, ether_sprintf(sc->sc_curbssid),
		 sc->sc_curaid);
}

static void
ath_set_channel(struct ieee80211com *ic)
{
	struct ifnet *ifp = ic->ic_ifp;
	struct ath_softc *sc = ifp->if_softc;

	(void) ath_chan_set(sc, ic->ic_curchan);
	/*
	 * If we are returning to our bss channel then mark state
	 * so the next recv'd beacon's tsf will be used to sync the
	 * beacon timers.  Note that since we only hear beacons in
	 * sta/ibss mode this has no effect in other operating modes.
	 */
	if (!sc->sc_scanning && ic->ic_curchan == ic->ic_bsschan)
		sc->sc_syncbeacon = 1;
}

/*
 * Walk the vap list and check if there any vap's in RUN state.
 */
static int
ath_isanyrunningvaps(struct ieee80211vap *this)
{
	struct ieee80211com *ic = this->iv_ic;
	struct ieee80211vap *vap;

	IEEE80211_LOCK_ASSERT(ic);

	TAILQ_FOREACH(vap, &ic->ic_vaps, iv_next) {
		if (vap != this && vap->iv_state == IEEE80211_S_RUN)
			return 1;
	}
	return 0;
}

static int
ath_newstate(struct ieee80211vap *vap, enum ieee80211_state nstate, int arg)
{
	struct ieee80211com *ic = vap->iv_ic;
	struct ath_softc *sc = ic->ic_ifp->if_softc;
	struct ath_vap *avp = ATH_VAP(vap);
	struct ath_hal *ah = sc->sc_ah;
	struct ieee80211_node *ni = NULL;
	int i, error, stamode;
	u_int32_t rfilt;
	static const HAL_LED_STATE leds[] = {
	    HAL_LED_INIT,	/* IEEE80211_S_INIT */
	    HAL_LED_SCAN,	/* IEEE80211_S_SCAN */
	    HAL_LED_AUTH,	/* IEEE80211_S_AUTH */
	    HAL_LED_ASSOC, 	/* IEEE80211_S_ASSOC */
	    HAL_LED_RUN, 	/* IEEE80211_S_CAC */
	    HAL_LED_RUN, 	/* IEEE80211_S_RUN */
	    HAL_LED_RUN, 	/* IEEE80211_S_CSA */
	    HAL_LED_RUN, 	/* IEEE80211_S_SLEEP */
	};

	DPRINTF(sc, ATH_DEBUG_STATE, "%s: %s -> %s\n", __func__,
		ieee80211_state_name[vap->iv_state],
		ieee80211_state_name[nstate]);

	callout_drain(&sc->sc_cal_ch);
	ath_hal_setledstate(ah, leds[nstate]);	/* set LED */

	if (nstate == IEEE80211_S_SCAN) {
		/*
		 * Scanning: turn off beacon miss and don't beacon.
		 * Mark beacon state so when we reach RUN state we'll
		 * [re]setup beacons.  Unblock the task q thread so
		 * deferred interrupt processing is done.
		 */
		ath_hal_intrset(ah,
		    sc->sc_imask &~ (HAL_INT_SWBA | HAL_INT_BMISS));
		sc->sc_imask &= ~(HAL_INT_SWBA | HAL_INT_BMISS);
		sc->sc_beacons = 0;
		taskqueue_unblock(sc->sc_tq);
	}

	ni = vap->iv_bss;
	rfilt = ath_calcrxfilter(sc);
	stamode = (vap->iv_opmode == IEEE80211_M_STA ||
		   vap->iv_opmode == IEEE80211_M_AHDEMO ||
		   vap->iv_opmode == IEEE80211_M_IBSS);
	if (stamode && nstate == IEEE80211_S_RUN) {
		sc->sc_curaid = ni->ni_associd;
		IEEE80211_ADDR_COPY(sc->sc_curbssid, ni->ni_bssid);
		ath_hal_setassocid(ah, sc->sc_curbssid, sc->sc_curaid);
	}
	DPRINTF(sc, ATH_DEBUG_STATE, "%s: RX filter 0x%x bssid %s aid 0x%x\n",
	   __func__, rfilt, ether_sprintf(sc->sc_curbssid), sc->sc_curaid);
	ath_hal_setrxfilter(ah, rfilt);

	/* XXX is this to restore keycache on resume? */
	if (vap->iv_opmode != IEEE80211_M_STA &&
	    (vap->iv_flags & IEEE80211_F_PRIVACY)) {
		for (i = 0; i < IEEE80211_WEP_NKID; i++)
			if (ath_hal_keyisvalid(ah, i))
				ath_hal_keysetmac(ah, i, ni->ni_bssid);
	}

	/*
	 * Invoke the parent method to do net80211 work.
	 */
	error = avp->av_newstate(vap, nstate, arg);
	if (error != 0)
		goto bad;

	if (nstate == IEEE80211_S_RUN) {
		/* NB: collect bss node again, it may have changed */
		ni = vap->iv_bss;

		DPRINTF(sc, ATH_DEBUG_STATE,
		    "%s(RUN): iv_flags 0x%08x bintvl %d bssid %s "
		    "capinfo 0x%04x chan %d\n", __func__,
		    vap->iv_flags, ni->ni_intval, ether_sprintf(ni->ni_bssid),
		    ni->ni_capinfo, ieee80211_chan2ieee(ic, ic->ic_curchan));

		switch (vap->iv_opmode) {
#ifdef IEEE80211_SUPPORT_TDMA
		case IEEE80211_M_AHDEMO:
			if ((vap->iv_caps & IEEE80211_C_TDMA) == 0)
				break;
			/* fall thru... */
#endif
		case IEEE80211_M_HOSTAP:
		case IEEE80211_M_IBSS:
			/*
			 * Allocate and setup the beacon frame.
			 *
			 * Stop any previous beacon DMA.  This may be
			 * necessary, for example, when an ibss merge
			 * causes reconfiguration; there will be a state
			 * transition from RUN->RUN that means we may
			 * be called with beacon transmission active.
			 */
			ath_hal_stoptxdma(ah, sc->sc_bhalq);

			error = ath_beacon_alloc(sc, ni);
			if (error != 0)
				goto bad;
			/*
			 * If joining an adhoc network defer beacon timer
			 * configuration to the next beacon frame so we
			 * have a current TSF to use.  Otherwise we're
			 * starting an ibss/bss so there's no need to delay;
			 * if this is the first vap moving to RUN state, then
			 * beacon state needs to be [re]configured.
			 */
			if (vap->iv_opmode == IEEE80211_M_IBSS &&
			    ni->ni_tstamp.tsf != 0) {
				sc->sc_syncbeacon = 1;
			} else if (!sc->sc_beacons) {
#ifdef IEEE80211_SUPPORT_TDMA
				if (vap->iv_caps & IEEE80211_C_TDMA)
					ath_tdma_config(sc, vap);
				else
#endif
					ath_beacon_config(sc, vap);
				sc->sc_beacons = 1;
			}
			break;
		case IEEE80211_M_STA:
			/*
			 * Defer beacon timer configuration to the next
			 * beacon frame so we have a current TSF to use
			 * (any TSF collected when scanning is likely old).
			 */
			sc->sc_syncbeacon = 1;
			break;
		case IEEE80211_M_MONITOR:
			/*
			 * Monitor mode vaps have only INIT->RUN and RUN->RUN
			 * transitions so we must re-enable interrupts here to
			 * handle the case of a single monitor mode vap.
			 */
			ath_hal_intrset(ah, sc->sc_imask);
			break;
		case IEEE80211_M_WDS:
			break;
		default:
			break;
		}
		/*
		 * Let the hal process statistics collected during a
		 * scan so it can provide calibrated noise floor data.
		 */
		ath_hal_process_noisefloor(ah);
		/*
		 * Reset rssi stats; maybe not the best place...
		 */
		sc->sc_halstats.ns_avgbrssi = ATH_RSSI_DUMMY_MARKER;
		sc->sc_halstats.ns_avgrssi = ATH_RSSI_DUMMY_MARKER;
		sc->sc_halstats.ns_avgtxrssi = ATH_RSSI_DUMMY_MARKER;
		/*
		 * Finally, start any timers and the task q thread
		 * (in case we didn't go through SCAN state).
		 */
		if (ath_longcalinterval != 0) {
			/* start periodic recalibration timer */
			callout_reset(&sc->sc_cal_ch, 1, ath_calibrate, sc);
		} else {
			DPRINTF(sc, ATH_DEBUG_CALIBRATE,
			    "%s: calibration disabled\n", __func__);
		}
		taskqueue_unblock(sc->sc_tq);
	} else if (nstate == IEEE80211_S_INIT) {
		/*
		 * If there are no vaps left in RUN state then
		 * shutdown host/driver operation:
		 * o disable interrupts
		 * o disable the task queue thread
		 * o mark beacon processing as stopped
		 */
		if (!ath_isanyrunningvaps(vap)) {
			sc->sc_imask &= ~(HAL_INT_SWBA | HAL_INT_BMISS);
			/* disable interrupts  */
			ath_hal_intrset(ah, sc->sc_imask &~ HAL_INT_GLOBAL);
			taskqueue_block(sc->sc_tq);
			sc->sc_beacons = 0;
		}
#ifdef IEEE80211_SUPPORT_TDMA
		ath_hal_setcca(ah, AH_TRUE);
#endif
	}
bad:
	return error;
}

/*
 * Allocate a key cache slot to the station so we can
 * setup a mapping from key index to node. The key cache
 * slot is needed for managing antenna state and for
 * compression when stations do not use crypto.  We do
 * it uniliaterally here; if crypto is employed this slot
 * will be reassigned.
 */
static void
ath_setup_stationkey(struct ieee80211_node *ni)
{
	struct ieee80211vap *vap = ni->ni_vap;
	struct ath_softc *sc = vap->iv_ic->ic_ifp->if_softc;
	ieee80211_keyix keyix, rxkeyix;

	if (!ath_key_alloc(vap, &ni->ni_ucastkey, &keyix, &rxkeyix)) {
		/*
		 * Key cache is full; we'll fall back to doing
		 * the more expensive lookup in software.  Note
		 * this also means no h/w compression.
		 */
		/* XXX msg+statistic */
	} else {
		/* XXX locking? */
		ni->ni_ucastkey.wk_keyix = keyix;
		ni->ni_ucastkey.wk_rxkeyix = rxkeyix;
		/* NB: must mark device key to get called back on delete */
		ni->ni_ucastkey.wk_flags |= IEEE80211_KEY_DEVKEY;
		IEEE80211_ADDR_COPY(ni->ni_ucastkey.wk_macaddr, ni->ni_macaddr);
		/* NB: this will create a pass-thru key entry */
		ath_keyset(sc, &ni->ni_ucastkey, vap->iv_bss);
	}
}

/*
 * Setup driver-specific state for a newly associated node.
 * Note that we're called also on a re-associate, the isnew
 * param tells us if this is the first time or not.
 */
static void
ath_newassoc(struct ieee80211_node *ni, int isnew)
{
	struct ath_node *an = ATH_NODE(ni);
	struct ieee80211vap *vap = ni->ni_vap;
	struct ath_softc *sc = vap->iv_ic->ic_ifp->if_softc;
	const struct ieee80211_txparam *tp = ni->ni_txparms;

	an->an_mcastrix = ath_tx_findrix(sc->sc_currates, tp->mcastrate);
	an->an_mgmtrix = ath_tx_findrix(sc->sc_currates, tp->mgmtrate);

	ath_rate_newassoc(sc, an, isnew);
	if (isnew &&
	    (vap->iv_flags & IEEE80211_F_PRIVACY) == 0 && sc->sc_hasclrkey &&
	    ni->ni_ucastkey.wk_keyix == IEEE80211_KEYIX_NONE)
		ath_setup_stationkey(ni);
}

static int
ath_setregdomain(struct ieee80211com *ic, struct ieee80211_regdomain *reg,
	int nchans, struct ieee80211_channel chans[])
{
	struct ath_softc *sc = ic->ic_ifp->if_softc;
	struct ath_hal *ah = sc->sc_ah;
	HAL_STATUS status;

	DPRINTF(sc, ATH_DEBUG_REGDOMAIN,
	    "%s: rd %u cc %u location %c%s\n",
	    __func__, reg->regdomain, reg->country, reg->location,
	    reg->ecm ? " ecm" : "");

	status = ath_hal_set_channels(ah, chans, nchans,
	    reg->country, reg->regdomain);
	if (status != HAL_OK) {
		DPRINTF(sc, ATH_DEBUG_REGDOMAIN, "%s: failed, status %u\n",
		    __func__, status);
		return EINVAL;		/* XXX */
	}
	return 0;
}

static void
ath_getradiocaps(struct ieee80211com *ic,
	int maxchans, int *nchans, struct ieee80211_channel chans[])
{
	struct ath_softc *sc = ic->ic_ifp->if_softc;
	struct ath_hal *ah = sc->sc_ah;

	DPRINTF(sc, ATH_DEBUG_REGDOMAIN, "%s: use rd %u cc %d\n",
	    __func__, SKU_DEBUG, CTRY_DEFAULT);

	/* XXX check return */
	(void) ath_hal_getchannels(ah, chans, maxchans, nchans,
	    HAL_MODE_ALL, CTRY_DEFAULT, SKU_DEBUG, AH_TRUE);

}

static int
ath_getchannels(struct ath_softc *sc)
{
	struct ifnet *ifp = sc->sc_ifp;
	struct ieee80211com *ic = ifp->if_l2com;
	struct ath_hal *ah = sc->sc_ah;
	HAL_STATUS status;

	/*
	 * Collect channel set based on EEPROM contents.
	 */
	status = ath_hal_init_channels(ah, ic->ic_channels, IEEE80211_CHAN_MAX,
	    &ic->ic_nchans, HAL_MODE_ALL, CTRY_DEFAULT, SKU_NONE, AH_TRUE);
	if (status != HAL_OK) {
		if_printf(ifp, "%s: unable to collect channel list from hal, "
		    "status %d\n", __func__, status);
		return EINVAL;
	}
	(void) ath_hal_getregdomain(ah, &sc->sc_eerd);
	ath_hal_getcountrycode(ah, &sc->sc_eecc);	/* NB: cannot fail */
	/* XXX map Atheros sku's to net80211 SKU's */
	/* XXX net80211 types too small */
	ic->ic_regdomain.regdomain = (uint16_t) sc->sc_eerd;
	ic->ic_regdomain.country = (uint16_t) sc->sc_eecc;
	ic->ic_regdomain.isocc[0] = ' ';	/* XXX don't know */
	ic->ic_regdomain.isocc[1] = ' ';

	ic->ic_regdomain.ecm = 1;
	ic->ic_regdomain.location = 'I';

	DPRINTF(sc, ATH_DEBUG_REGDOMAIN,
	    "%s: eeprom rd %u cc %u (mapped rd %u cc %u) location %c%s\n",
	    __func__, sc->sc_eerd, sc->sc_eecc,
	    ic->ic_regdomain.regdomain, ic->ic_regdomain.country,
	    ic->ic_regdomain.location, ic->ic_regdomain.ecm ? " ecm" : "");
	return 0;
}

static void
ath_led_done(void *arg)
{
	struct ath_softc *sc = arg;

	sc->sc_blinking = 0;
}

/*
 * Turn the LED off: flip the pin and then set a timer so no
 * update will happen for the specified duration.
 */
static void
ath_led_off(void *arg)
{
	struct ath_softc *sc = arg;

	ath_hal_gpioset(sc->sc_ah, sc->sc_ledpin, !sc->sc_ledon);
	callout_reset(&sc->sc_ledtimer, sc->sc_ledoff, ath_led_done, sc);
}

/*
 * Blink the LED according to the specified on/off times.
 */
static void
ath_led_blink(struct ath_softc *sc, int on, int off)
{
	DPRINTF(sc, ATH_DEBUG_LED, "%s: on %u off %u\n", __func__, on, off);
	ath_hal_gpioset(sc->sc_ah, sc->sc_ledpin, sc->sc_ledon);
	sc->sc_blinking = 1;
	sc->sc_ledoff = off;
	callout_reset(&sc->sc_ledtimer, on, ath_led_off, sc);
}

static void
ath_led_event(struct ath_softc *sc, int rix)
{
	sc->sc_ledevent = ticks;	/* time of last event */
	if (sc->sc_blinking)		/* don't interrupt active blink */
		return;
	ath_led_blink(sc, sc->sc_hwmap[rix].ledon, sc->sc_hwmap[rix].ledoff);
}

static int
ath_rate_setup(struct ath_softc *sc, u_int mode)
{
	struct ath_hal *ah = sc->sc_ah;
	const HAL_RATE_TABLE *rt;

	switch (mode) {
	case IEEE80211_MODE_11A:
		rt = ath_hal_getratetable(ah, HAL_MODE_11A);
		break;
	case IEEE80211_MODE_HALF:
		rt = ath_hal_getratetable(ah, HAL_MODE_11A_HALF_RATE);
		break;
	case IEEE80211_MODE_QUARTER:
		rt = ath_hal_getratetable(ah, HAL_MODE_11A_QUARTER_RATE);
		break;
	case IEEE80211_MODE_11B:
		rt = ath_hal_getratetable(ah, HAL_MODE_11B);
		break;
	case IEEE80211_MODE_11G:
		rt = ath_hal_getratetable(ah, HAL_MODE_11G);
		break;
	case IEEE80211_MODE_TURBO_A:
		rt = ath_hal_getratetable(ah, HAL_MODE_108A);
		break;
	case IEEE80211_MODE_TURBO_G:
		rt = ath_hal_getratetable(ah, HAL_MODE_108G);
		break;
	case IEEE80211_MODE_STURBO_A:
		rt = ath_hal_getratetable(ah, HAL_MODE_TURBO);
		break;
	case IEEE80211_MODE_11NA:
		rt = ath_hal_getratetable(ah, HAL_MODE_11NA_HT20);
		break;
	case IEEE80211_MODE_11NG:
		rt = ath_hal_getratetable(ah, HAL_MODE_11NG_HT20);
		break;
	default:
		DPRINTF(sc, ATH_DEBUG_ANY, "%s: invalid mode %u\n",
			__func__, mode);
		return 0;
	}
	sc->sc_rates[mode] = rt;
	return (rt != NULL);
}

static void
ath_setcurmode(struct ath_softc *sc, enum ieee80211_phymode mode)
{
#define	N(a)	(sizeof(a)/sizeof(a[0]))
	/* NB: on/off times from the Atheros NDIS driver, w/ permission */
	static const struct {
		u_int		rate;		/* tx/rx 802.11 rate */
		u_int16_t	timeOn;		/* LED on time (ms) */
		u_int16_t	timeOff;	/* LED off time (ms) */
	} blinkrates[] = {
		{ 108,  40,  10 },
		{  96,  44,  11 },
		{  72,  50,  13 },
		{  48,  57,  14 },
		{  36,  67,  16 },
		{  24,  80,  20 },
		{  22, 100,  25 },
		{  18, 133,  34 },
		{  12, 160,  40 },
		{  10, 200,  50 },
		{   6, 240,  58 },
		{   4, 267,  66 },
		{   2, 400, 100 },
		{   0, 500, 130 },
		/* XXX half/quarter rates */
	};
	const HAL_RATE_TABLE *rt;
	int i, j;

	memset(sc->sc_rixmap, 0xff, sizeof(sc->sc_rixmap));
	rt = sc->sc_rates[mode];
	KASSERT(rt != NULL, ("no h/w rate set for phy mode %u", mode));
	for (i = 0; i < rt->rateCount; i++) {
		uint8_t ieeerate = rt->info[i].dot11Rate & IEEE80211_RATE_VAL;
		if (rt->info[i].phy != IEEE80211_T_HT)
			sc->sc_rixmap[ieeerate] = i;
		else
			sc->sc_rixmap[ieeerate | IEEE80211_RATE_MCS] = i;
	}
	memset(sc->sc_hwmap, 0, sizeof(sc->sc_hwmap));
	for (i = 0; i < N(sc->sc_hwmap); i++) {
		if (i >= rt->rateCount) {
			sc->sc_hwmap[i].ledon = (500 * hz) / 1000;
			sc->sc_hwmap[i].ledoff = (130 * hz) / 1000;
			continue;
		}
		sc->sc_hwmap[i].ieeerate =
			rt->info[i].dot11Rate & IEEE80211_RATE_VAL;
		if (rt->info[i].phy == IEEE80211_T_HT)
			sc->sc_hwmap[i].ieeerate |= IEEE80211_RATE_MCS;
		sc->sc_hwmap[i].txflags = IEEE80211_RADIOTAP_F_DATAPAD;
		if (rt->info[i].shortPreamble ||
		    rt->info[i].phy == IEEE80211_T_OFDM)
			sc->sc_hwmap[i].txflags |= IEEE80211_RADIOTAP_F_SHORTPRE;
		/* NB: receive frames include FCS */
		sc->sc_hwmap[i].rxflags = sc->sc_hwmap[i].txflags |
			IEEE80211_RADIOTAP_F_FCS;
		/* setup blink rate table to avoid per-packet lookup */
		for (j = 0; j < N(blinkrates)-1; j++)
			if (blinkrates[j].rate == sc->sc_hwmap[i].ieeerate)
				break;
		/* NB: this uses the last entry if the rate isn't found */
		/* XXX beware of overlow */
		sc->sc_hwmap[i].ledon = (blinkrates[j].timeOn * hz) / 1000;
		sc->sc_hwmap[i].ledoff = (blinkrates[j].timeOff * hz) / 1000;
	}
	sc->sc_currates = rt;
	sc->sc_curmode = mode;
	/*
	 * All protection frames are transmited at 2Mb/s for
	 * 11g, otherwise at 1Mb/s.
	 */
	if (mode == IEEE80211_MODE_11G)
		sc->sc_protrix = ath_tx_findrix(rt, 2*2);
	else
		sc->sc_protrix = ath_tx_findrix(rt, 2*1);
	/* NB: caller is responsible for reseting rate control state */
#undef N
}

#ifdef ATH_DEBUG
static void
ath_printrxbuf(struct ath_softc *sc, const struct ath_buf *bf,
	u_int ix, int done)
{
	const struct ath_rx_status *rs = &bf->bf_status.ds_rxstat;
	struct ath_hal *ah = sc->sc_ah;
	const struct ath_desc *ds;
	int i;

	for (i = 0, ds = bf->bf_desc; i < bf->bf_nseg; i++, ds++) {
		printf("R[%2u] (DS.V:%p DS.P:%p) L:%08x D:%08x%s\n"
		       "      %08x %08x %08x %08x\n",
		    ix, ds, (const struct ath_desc *)bf->bf_daddr + i,
		    ds->ds_link, ds->ds_data,
		    !done ? "" : (rs->rs_status == 0) ? " *" : " !",
		    ds->ds_ctl0, ds->ds_ctl1,
		    ds->ds_hw[0], ds->ds_hw[1]);
		if (ah->ah_magic == 0x20065416) {
			printf("        %08x %08x %08x %08x %08x %08x %08x\n",
			    ds->ds_hw[2], ds->ds_hw[3], ds->ds_hw[4],
			    ds->ds_hw[5], ds->ds_hw[6], ds->ds_hw[7],
			    ds->ds_hw[8]);
		}
	}
}

static void
ath_printtxbuf(struct ath_softc *sc, const struct ath_buf *bf,
	u_int qnum, u_int ix, int done)
{
	const struct ath_tx_status *ts = &bf->bf_status.ds_txstat;
	struct ath_hal *ah = sc->sc_ah;
	const struct ath_desc *ds;
	int i;

	printf("Q%u[%3u]", qnum, ix);
	for (i = 0, ds = bf->bf_desc; i < bf->bf_nseg; i++, ds++) {
		printf(" (DS.V:%p DS.P:%p) L:%08x D:%08x F:04%x%s\n"
		       "        %08x %08x %08x %08x %08x %08x\n",
		    ds, (const struct ath_desc *)bf->bf_daddr + i,
		    ds->ds_link, ds->ds_data, bf->bf_txflags,
		    !done ? "" : (ts->ts_status == 0) ? " *" : " !",
		    ds->ds_ctl0, ds->ds_ctl1,
		    ds->ds_hw[0], ds->ds_hw[1], ds->ds_hw[2], ds->ds_hw[3]);
		if (ah->ah_magic == 0x20065416) {
			printf("        %08x %08x %08x %08x %08x %08x %08x %08x\n",
			    ds->ds_hw[4], ds->ds_hw[5], ds->ds_hw[6],
			    ds->ds_hw[7], ds->ds_hw[8], ds->ds_hw[9],
			    ds->ds_hw[10],ds->ds_hw[11]);
			printf("        %08x %08x %08x %08x %08x %08x %08x %08x\n",
			    ds->ds_hw[12],ds->ds_hw[13],ds->ds_hw[14],
			    ds->ds_hw[15],ds->ds_hw[16],ds->ds_hw[17],
			    ds->ds_hw[18], ds->ds_hw[19]);
		}
	}
}
#endif /* ATH_DEBUG */

static void
ath_watchdog(void *arg)
{
	struct ath_softc *sc = arg;

	if (sc->sc_wd_timer != 0 && --sc->sc_wd_timer == 0) {
		struct ifnet *ifp = sc->sc_ifp;
		uint32_t hangs;

		if (ath_hal_gethangstate(sc->sc_ah, 0xffff, &hangs) &&
		    hangs != 0) {
			if_printf(ifp, "%s hang detected (0x%x)\n",
			    hangs & 0xff ? "bb" : "mac", hangs);
		} else
			if_printf(ifp, "device timeout\n");
		ath_reset(ifp);
		ifp->if_oerrors++;
		sc->sc_stats.ast_watchdog++;
	}
	callout_schedule(&sc->sc_wd_ch, hz);
}

#ifdef ATH_DIAGAPI
/*
 * Diagnostic interface to the HAL.  This is used by various
 * tools to do things like retrieve register contents for
 * debugging.  The mechanism is intentionally opaque so that
 * it can change frequently w/o concern for compatiblity.
 */
static int
ath_ioctl_diag(struct ath_softc *sc, struct ath_diag *ad)
{
	struct ath_hal *ah = sc->sc_ah;
	u_int id = ad->ad_id & ATH_DIAG_ID;
	void *indata = NULL;
	void *outdata = NULL;
	u_int32_t insize = ad->ad_in_size;
	u_int32_t outsize = ad->ad_out_size;
	int error = 0;

	if (ad->ad_id & ATH_DIAG_IN) {
		/*
		 * Copy in data.
		 */
		indata = malloc(insize, M_TEMP, M_NOWAIT);
		if (indata == NULL) {
			error = ENOMEM;
			goto bad;
		}
		error = copyin(ad->ad_in_data, indata, insize);
		if (error)
			goto bad;
	}
	if (ad->ad_id & ATH_DIAG_DYN) {
		/*
		 * Allocate a buffer for the results (otherwise the HAL
		 * returns a pointer to a buffer where we can read the
		 * results).  Note that we depend on the HAL leaving this
		 * pointer for us to use below in reclaiming the buffer;
		 * may want to be more defensive.
		 */
		outdata = malloc(outsize, M_TEMP, M_NOWAIT);
		if (outdata == NULL) {
			error = ENOMEM;
			goto bad;
		}
	}
	if (ath_hal_getdiagstate(ah, id, indata, insize, &outdata, &outsize)) {
		if (outsize < ad->ad_out_size)
			ad->ad_out_size = outsize;
		if (outdata != NULL)
			error = copyout(outdata, ad->ad_out_data,
					ad->ad_out_size);
	} else {
		error = EINVAL;
	}
bad:
	if ((ad->ad_id & ATH_DIAG_IN) && indata != NULL)
		free(indata, M_TEMP);
	if ((ad->ad_id & ATH_DIAG_DYN) && outdata != NULL)
		free(outdata, M_TEMP);
	return error;
}
#endif /* ATH_DIAGAPI */

static int
ath_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data)
{
#define	IS_RUNNING(ifp) \
	((ifp->if_flags & IFF_UP) && (ifp->if_drv_flags & IFF_DRV_RUNNING))
	struct ath_softc *sc = ifp->if_softc;
	struct ieee80211com *ic = ifp->if_l2com;
	struct ifreq *ifr = (struct ifreq *)data;
	const HAL_RATE_TABLE *rt;
	int error = 0;

	switch (cmd) {
	case SIOCSIFFLAGS:
		ATH_LOCK(sc);
		if (IS_RUNNING(ifp)) {
			/*
			 * To avoid rescanning another access point,
			 * do not call ath_init() here.  Instead,
			 * only reflect promisc mode settings.
			 */
			ath_mode_init(sc);
		} else if (ifp->if_flags & IFF_UP) {
			/*
			 * Beware of being called during attach/detach
			 * to reset promiscuous mode.  In that case we
			 * will still be marked UP but not RUNNING.
			 * However trying to re-init the interface
			 * is the wrong thing to do as we've already
			 * torn down much of our state.  There's
			 * probably a better way to deal with this.
			 */
			if (!sc->sc_invalid)
				ath_init(sc);	/* XXX lose error */
		} else {
			ath_stop_locked(ifp);
#ifdef notyet
			/* XXX must wakeup in places like ath_vap_delete */
			if (!sc->sc_invalid)
				ath_hal_setpower(sc->sc_ah, HAL_PM_FULL_SLEEP);
#endif
		}
		ATH_UNLOCK(sc);
		break;
	case SIOCGIFMEDIA:
	case SIOCSIFMEDIA:
		error = ifmedia_ioctl(ifp, ifr, &ic->ic_media, cmd);
		break;
	case SIOCGATHSTATS:
		/* NB: embed these numbers to get a consistent view */
		sc->sc_stats.ast_tx_packets = ifp->if_opackets;
		sc->sc_stats.ast_rx_packets = ifp->if_ipackets;
		sc->sc_stats.ast_tx_rssi = ATH_RSSI(sc->sc_halstats.ns_avgtxrssi);
		sc->sc_stats.ast_rx_rssi = ATH_RSSI(sc->sc_halstats.ns_avgrssi);
#ifdef IEEE80211_SUPPORT_TDMA
		sc->sc_stats.ast_tdma_tsfadjp = TDMA_AVG(sc->sc_avgtsfdeltap);
		sc->sc_stats.ast_tdma_tsfadjm = TDMA_AVG(sc->sc_avgtsfdeltam);
#endif
		rt = sc->sc_currates;
		/* XXX HT rates */
		sc->sc_stats.ast_tx_rate =
		    rt->info[sc->sc_txrix].dot11Rate &~ IEEE80211_RATE_BASIC;
		return copyout(&sc->sc_stats,
		    ifr->ifr_data, sizeof (sc->sc_stats));
	case SIOCZATHSTATS:
		error = priv_check(curthread, PRIV_DRIVER);
		if (error == 0)
			memset(&sc->sc_stats, 0, sizeof(sc->sc_stats));
		break;
#ifdef ATH_DIAGAPI
	case SIOCGATHDIAG:
		error = ath_ioctl_diag(sc, (struct ath_diag *) ifr);
		break;
#endif
	case SIOCGIFADDR:
		error = ether_ioctl(ifp, cmd, data);
		break;
	default:
		error = EINVAL;
		break;
	}
	return error;
#undef IS_RUNNING
}

static int
ath_sysctl_slottime(SYSCTL_HANDLER_ARGS)
{
	struct ath_softc *sc = arg1;
	u_int slottime = ath_hal_getslottime(sc->sc_ah);
	int error;

	error = sysctl_handle_int(oidp, &slottime, 0, req);
	if (error || !req->newptr)
		return error;
	return !ath_hal_setslottime(sc->sc_ah, slottime) ? EINVAL : 0;
}

static int
ath_sysctl_acktimeout(SYSCTL_HANDLER_ARGS)
{
	struct ath_softc *sc = arg1;
	u_int acktimeout = ath_hal_getacktimeout(sc->sc_ah);
	int error;

	error = sysctl_handle_int(oidp, &acktimeout, 0, req);
	if (error || !req->newptr)
		return error;
	return !ath_hal_setacktimeout(sc->sc_ah, acktimeout) ? EINVAL : 0;
}

static int
ath_sysctl_ctstimeout(SYSCTL_HANDLER_ARGS)
{
	struct ath_softc *sc = arg1;
	u_int ctstimeout = ath_hal_getctstimeout(sc->sc_ah);
	int error;

	error = sysctl_handle_int(oidp, &ctstimeout, 0, req);
	if (error || !req->newptr)
		return error;
	return !ath_hal_setctstimeout(sc->sc_ah, ctstimeout) ? EINVAL : 0;
}

static int
ath_sysctl_softled(SYSCTL_HANDLER_ARGS)
{
	struct ath_softc *sc = arg1;
	int softled = sc->sc_softled;
	int error;

	error = sysctl_handle_int(oidp, &softled, 0, req);
	if (error || !req->newptr)
		return error;
	softled = (softled != 0);
	if (softled != sc->sc_softled) {
		if (softled) {
			/* NB: handle any sc_ledpin change */
			ath_hal_gpioCfgOutput(sc->sc_ah, sc->sc_ledpin,
			    HAL_GPIO_MUX_MAC_NETWORK_LED);
			ath_hal_gpioset(sc->sc_ah, sc->sc_ledpin,
				!sc->sc_ledon);
		}
		sc->sc_softled = softled;
	}
	return 0;
}

static int
ath_sysctl_ledpin(SYSCTL_HANDLER_ARGS)
{
	struct ath_softc *sc = arg1;
	int ledpin = sc->sc_ledpin;
	int error;

	error = sysctl_handle_int(oidp, &ledpin, 0, req);
	if (error || !req->newptr)
		return error;
	if (ledpin != sc->sc_ledpin) {
		sc->sc_ledpin = ledpin;
		if (sc->sc_softled) {
			ath_hal_gpioCfgOutput(sc->sc_ah, sc->sc_ledpin,
			    HAL_GPIO_MUX_MAC_NETWORK_LED);
			ath_hal_gpioset(sc->sc_ah, sc->sc_ledpin,
				!sc->sc_ledon);
		}
	}
	return 0;
}

static int
ath_sysctl_txantenna(SYSCTL_HANDLER_ARGS)
{
	struct ath_softc *sc = arg1;
	u_int txantenna = ath_hal_getantennaswitch(sc->sc_ah);
	int error;

	error = sysctl_handle_int(oidp, &txantenna, 0, req);
	if (!error && req->newptr) {
		/* XXX assumes 2 antenna ports */
		if (txantenna < HAL_ANT_VARIABLE || txantenna > HAL_ANT_FIXED_B)
			return EINVAL;
		ath_hal_setantennaswitch(sc->sc_ah, txantenna);
		/*
		 * NB: with the switch locked this isn't meaningful,
		 *     but set it anyway so things like radiotap get
		 *     consistent info in their data.
		 */
		sc->sc_txantenna = txantenna;
	}
	return error;
}

static int
ath_sysctl_rxantenna(SYSCTL_HANDLER_ARGS)
{
	struct ath_softc *sc = arg1;
	u_int defantenna = ath_hal_getdefantenna(sc->sc_ah);
	int error;

	error = sysctl_handle_int(oidp, &defantenna, 0, req);
	if (!error && req->newptr)
		ath_hal_setdefantenna(sc->sc_ah, defantenna);
	return error;
}

static int
ath_sysctl_diversity(SYSCTL_HANDLER_ARGS)
{
	struct ath_softc *sc = arg1;
	u_int diversity = ath_hal_getdiversity(sc->sc_ah);
	int error;

	error = sysctl_handle_int(oidp, &diversity, 0, req);
	if (error || !req->newptr)
		return error;
	if (!ath_hal_setdiversity(sc->sc_ah, diversity))
		return EINVAL;
	sc->sc_diversity = diversity;
	return 0;
}

static int
ath_sysctl_diag(SYSCTL_HANDLER_ARGS)
{
	struct ath_softc *sc = arg1;
	u_int32_t diag;
	int error;

	if (!ath_hal_getdiag(sc->sc_ah, &diag))
		return EINVAL;
	error = sysctl_handle_int(oidp, &diag, 0, req);
	if (error || !req->newptr)
		return error;
	return !ath_hal_setdiag(sc->sc_ah, diag) ? EINVAL : 0;
}

static int
ath_sysctl_tpscale(SYSCTL_HANDLER_ARGS)
{
	struct ath_softc *sc = arg1;
	struct ifnet *ifp = sc->sc_ifp;
	u_int32_t scale;
	int error;

	(void) ath_hal_gettpscale(sc->sc_ah, &scale);
	error = sysctl_handle_int(oidp, &scale, 0, req);
	if (error || !req->newptr)
		return error;
	return !ath_hal_settpscale(sc->sc_ah, scale) ? EINVAL :
	    (ifp->if_drv_flags & IFF_DRV_RUNNING) ? ath_reset(ifp) : 0;
}

static int
ath_sysctl_tpc(SYSCTL_HANDLER_ARGS)
{
	struct ath_softc *sc = arg1;
	u_int tpc = ath_hal_gettpc(sc->sc_ah);
	int error;

	error = sysctl_handle_int(oidp, &tpc, 0, req);
	if (error || !req->newptr)
		return error;
	return !ath_hal_settpc(sc->sc_ah, tpc) ? EINVAL : 0;
}

static int
ath_sysctl_rfkill(SYSCTL_HANDLER_ARGS)
{
	struct ath_softc *sc = arg1;
	struct ifnet *ifp = sc->sc_ifp;
	struct ath_hal *ah = sc->sc_ah;
	u_int rfkill = ath_hal_getrfkill(ah);
	int error;

	error = sysctl_handle_int(oidp, &rfkill, 0, req);
	if (error || !req->newptr)
		return error;
	if (rfkill == ath_hal_getrfkill(ah))	/* unchanged */
		return 0;
	if (!ath_hal_setrfkill(ah, rfkill))
		return EINVAL;
	return (ifp->if_drv_flags & IFF_DRV_RUNNING) ? ath_reset(ifp) : 0;
}

static int
ath_sysctl_rfsilent(SYSCTL_HANDLER_ARGS)
{
	struct ath_softc *sc = arg1;
	u_int rfsilent;
	int error;

	(void) ath_hal_getrfsilent(sc->sc_ah, &rfsilent);
	error = sysctl_handle_int(oidp, &rfsilent, 0, req);
	if (error || !req->newptr)
		return error;
	if (!ath_hal_setrfsilent(sc->sc_ah, rfsilent))
		return EINVAL;
	sc->sc_rfsilentpin = rfsilent & 0x1c;
	sc->sc_rfsilentpol = (rfsilent & 0x2) != 0;
	return 0;
}

static int
ath_sysctl_tpack(SYSCTL_HANDLER_ARGS)
{
	struct ath_softc *sc = arg1;
	u_int32_t tpack;
	int error;

	(void) ath_hal_gettpack(sc->sc_ah, &tpack);
	error = sysctl_handle_int(oidp, &tpack, 0, req);
	if (error || !req->newptr)
		return error;
	return !ath_hal_settpack(sc->sc_ah, tpack) ? EINVAL : 0;
}

static int
ath_sysctl_tpcts(SYSCTL_HANDLER_ARGS)
{
	struct ath_softc *sc = arg1;
	u_int32_t tpcts;
	int error;

	(void) ath_hal_gettpcts(sc->sc_ah, &tpcts);
	error = sysctl_handle_int(oidp, &tpcts, 0, req);
	if (error || !req->newptr)
		return error;
	return !ath_hal_settpcts(sc->sc_ah, tpcts) ? EINVAL : 0;
}

static int
ath_sysctl_intmit(SYSCTL_HANDLER_ARGS)
{
	struct ath_softc *sc = arg1;
	int intmit, error;

	intmit = ath_hal_getintmit(sc->sc_ah);
	error = sysctl_handle_int(oidp, &intmit, 0, req);
	if (error || !req->newptr)
		return error;
	return !ath_hal_setintmit(sc->sc_ah, intmit) ? EINVAL : 0;
}

#ifdef IEEE80211_SUPPORT_TDMA
static int
ath_sysctl_setcca(SYSCTL_HANDLER_ARGS)
{
	struct ath_softc *sc = arg1;
	int setcca, error;

	setcca = sc->sc_setcca;
	error = sysctl_handle_int(oidp, &setcca, 0, req);
	if (error || !req->newptr)
		return error;
	sc->sc_setcca = (setcca != 0);
	return 0;
}
#endif /* IEEE80211_SUPPORT_TDMA */

static void
ath_sysctlattach(struct ath_softc *sc)
{
	struct sysctl_ctx_list *ctx = device_get_sysctl_ctx(sc->sc_dev);
	struct sysctl_oid *tree = device_get_sysctl_tree(sc->sc_dev);
	struct ath_hal *ah = sc->sc_ah;

	SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
		"countrycode", CTLFLAG_RD, &sc->sc_eecc, 0,
		"EEPROM country code");
	SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
		"regdomain", CTLFLAG_RD, &sc->sc_eerd, 0,
		"EEPROM regdomain code");
#ifdef	ATH_DEBUG
	SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
		"debug", CTLFLAG_RW, &sc->sc_debug, 0,
		"control debugging printfs");
#endif
	SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
		"slottime", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
		ath_sysctl_slottime, "I", "802.11 slot time (us)");
	SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
		"acktimeout", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
		ath_sysctl_acktimeout, "I", "802.11 ACK timeout (us)");
	SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
		"ctstimeout", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
		ath_sysctl_ctstimeout, "I", "802.11 CTS timeout (us)");
	SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
		"softled", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
		ath_sysctl_softled, "I", "enable/disable software LED support");
	SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
		"ledpin", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
		ath_sysctl_ledpin, "I", "GPIO pin connected to LED");
	SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
		"ledon", CTLFLAG_RW, &sc->sc_ledon, 0,
		"setting to turn LED on");
	SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
		"ledidle", CTLFLAG_RW, &sc->sc_ledidle, 0,
		"idle time for inactivity LED (ticks)");
	SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
		"txantenna", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
		ath_sysctl_txantenna, "I", "antenna switch");
	SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
		"rxantenna", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
		ath_sysctl_rxantenna, "I", "default/rx antenna");
	if (ath_hal_hasdiversity(ah))
		SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
			"diversity", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
			ath_sysctl_diversity, "I", "antenna diversity");
	sc->sc_txintrperiod = ATH_TXINTR_PERIOD;
	SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
		"txintrperiod", CTLFLAG_RW, &sc->sc_txintrperiod, 0,
		"tx descriptor batching");
	SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
		"diag", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
		ath_sysctl_diag, "I", "h/w diagnostic control");
	SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
		"tpscale", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
		ath_sysctl_tpscale, "I", "tx power scaling");
	if (ath_hal_hastpc(ah)) {
		SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
			"tpc", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
			ath_sysctl_tpc, "I", "enable/disable per-packet TPC");
		SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
			"tpack", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
			ath_sysctl_tpack, "I", "tx power for ack frames");
		SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
			"tpcts", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
			ath_sysctl_tpcts, "I", "tx power for cts frames");
	}
	if (ath_hal_hasfastframes(sc->sc_ah)) {
		sc->sc_fftxqmin = ATH_FF_TXQMIN;
		SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
			"fftxqmin", CTLFLAG_RW, &sc->sc_fftxqmin, 0,
			"min frames before fast-frame staging");
		sc->sc_fftxqmax = ATH_FF_TXQMAX;
		SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
			"fftxqmax", CTLFLAG_RW, &sc->sc_fftxqmax, 0,
			"max queued frames before tail drop");
	}
	if (ath_hal_hasrfsilent(ah)) {
		SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
			"rfsilent", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
			ath_sysctl_rfsilent, "I", "h/w RF silent config");
		SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
			"rfkill", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
			ath_sysctl_rfkill, "I", "enable/disable RF kill switch");
	}
	if (ath_hal_hasintmit(ah)) {
		SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
			"intmit", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
			ath_sysctl_intmit, "I", "interference mitigation");
	}
	sc->sc_monpass = HAL_RXERR_DECRYPT | HAL_RXERR_MIC;
	SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
		"monpass", CTLFLAG_RW, &sc->sc_monpass, 0,
		"mask of error frames to pass when monitoring");
#ifdef IEEE80211_SUPPORT_TDMA
	if (ath_hal_macversion(ah) > 0x78) {
		sc->sc_tdmadbaprep = 2;
		SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
			"dbaprep", CTLFLAG_RW, &sc->sc_tdmadbaprep, 0,
			"TDMA DBA preparation time");
		sc->sc_tdmaswbaprep = 10;
		SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
			"swbaprep", CTLFLAG_RW, &sc->sc_tdmaswbaprep, 0,
			"TDMA SWBA preparation time");
		SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
			"guardtime", CTLFLAG_RW, &sc->sc_tdmaguard, 0,
			"TDMA slot guard time");
		SYSCTL_ADD_INT(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
			"superframe", CTLFLAG_RD, &sc->sc_tdmabintval, 0,
			"TDMA calculated super frame");
		SYSCTL_ADD_PROC(ctx, SYSCTL_CHILDREN(tree), OID_AUTO,
			"setcca", CTLTYPE_INT | CTLFLAG_RW, sc, 0,
			ath_sysctl_setcca, "I", "enable CCA control");
	}
#endif
}

static void
ath_bpfattach(struct ath_softc *sc)
{
	struct ifnet *ifp = sc->sc_ifp;

	bpfattach(ifp, DLT_IEEE802_11_RADIO,
		sizeof(struct ieee80211_frame) + sizeof(sc->sc_tx_th));
	/*
	 * Initialize constant fields.
	 * XXX make header lengths a multiple of 32-bits so subsequent
	 *     headers are properly aligned; this is a kludge to keep
	 *     certain applications happy.
	 *
	 * NB: the channel is setup each time we transition to the
	 *     RUN state to avoid filling it in for each frame.
	 */
	sc->sc_tx_th_len = roundup(sizeof(sc->sc_tx_th), sizeof(u_int32_t));
	sc->sc_tx_th.wt_ihdr.it_len = htole16(sc->sc_tx_th_len);
	sc->sc_tx_th.wt_ihdr.it_present = htole32(ATH_TX_RADIOTAP_PRESENT);

	sc->sc_rx_th_len = roundup(sizeof(sc->sc_rx_th), sizeof(u_int32_t));
	sc->sc_rx_th.wr_ihdr.it_len = htole16(sc->sc_rx_th_len);
	sc->sc_rx_th.wr_ihdr.it_present = htole32(ATH_RX_RADIOTAP_PRESENT);
}

static int
ath_tx_raw_start(struct ath_softc *sc, struct ieee80211_node *ni,
	struct ath_buf *bf, struct mbuf *m0,
	const struct ieee80211_bpf_params *params)
{
	struct ifnet *ifp = sc->sc_ifp;
	struct ieee80211com *ic = ifp->if_l2com;
	struct ath_hal *ah = sc->sc_ah;
	int error, ismcast, ismrr;
	int keyix, hdrlen, pktlen, try0, txantenna;
	u_int8_t rix, cix, txrate, ctsrate, rate1, rate2, rate3;
	struct ieee80211_frame *wh;
	u_int flags, ctsduration;
	HAL_PKT_TYPE atype;
	const HAL_RATE_TABLE *rt;
	struct ath_desc *ds;
	u_int pri;

	wh = mtod(m0, struct ieee80211_frame *);
	ismcast = IEEE80211_IS_MULTICAST(wh->i_addr1);
	hdrlen = ieee80211_anyhdrsize(wh);
	/*
	 * Packet length must not include any
	 * pad bytes; deduct them here.
	 */
	/* XXX honor IEEE80211_BPF_DATAPAD */
	pktlen = m0->m_pkthdr.len - (hdrlen & 3) + IEEE80211_CRC_LEN;

	if (params->ibp_flags & IEEE80211_BPF_CRYPTO) {
		const struct ieee80211_cipher *cip;
		struct ieee80211_key *k;

		/*
		 * Construct the 802.11 header+trailer for an encrypted
		 * frame. The only reason this can fail is because of an
		 * unknown or unsupported cipher/key type.
		 */
		k = ieee80211_crypto_encap(ni, m0);
		if (k == NULL) {
			/*
			 * This can happen when the key is yanked after the
			 * frame was queued.  Just discard the frame; the
			 * 802.11 layer counts failures and provides
			 * debugging/diagnostics.
			 */
			ath_freetx(m0);
			return EIO;
		}
		/*
		 * Adjust the packet + header lengths for the crypto
		 * additions and calculate the h/w key index.  When
		 * a s/w mic is done the frame will have had any mic
		 * added to it prior to entry so m0->m_pkthdr.len will
		 * account for it. Otherwise we need to add it to the
		 * packet length.
		 */
		cip = k->wk_cipher;
		hdrlen += cip->ic_header;
		pktlen += cip->ic_header + cip->ic_trailer;
		/* NB: frags always have any TKIP MIC done in s/w */
		if ((k->wk_flags & IEEE80211_KEY_SWMIC) == 0)
			pktlen += cip->ic_miclen;
		keyix = k->wk_keyix;

		/* packet header may have moved, reset our local pointer */
		wh = mtod(m0, struct ieee80211_frame *);
	} else if (ni->ni_ucastkey.wk_cipher == &ieee80211_cipher_none) {
		/*
		 * Use station key cache slot, if assigned.
		 */
		keyix = ni->ni_ucastkey.wk_keyix;
		if (keyix == IEEE80211_KEYIX_NONE)
			keyix = HAL_TXKEYIX_INVALID;
	} else
		keyix = HAL_TXKEYIX_INVALID;

	error = ath_tx_dmasetup(sc, bf, m0);
	if (error != 0)
		return error;
	m0 = bf->bf_m;				/* NB: may have changed */
	wh = mtod(m0, struct ieee80211_frame *);
	bf->bf_node = ni;			/* NB: held reference */

	flags = HAL_TXDESC_CLRDMASK;		/* XXX needed for crypto errs */
	flags |= HAL_TXDESC_INTREQ;		/* force interrupt */
	if (params->ibp_flags & IEEE80211_BPF_RTS)
		flags |= HAL_TXDESC_RTSENA;
	else if (params->ibp_flags & IEEE80211_BPF_CTS)
		flags |= HAL_TXDESC_CTSENA;
	/* XXX leave ismcast to injector? */
	if ((params->ibp_flags & IEEE80211_BPF_NOACK) || ismcast)
		flags |= HAL_TXDESC_NOACK;

	rt = sc->sc_currates;
	KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode));
	rix = ath_tx_findrix(rt, params->ibp_rate0);
	txrate = rt->info[rix].rateCode;
	if (params->ibp_flags & IEEE80211_BPF_SHORTPRE)
		txrate |= rt->info[rix].shortPreamble;
	sc->sc_txrix = rix;
	try0 = params->ibp_try0;
	ismrr = (params->ibp_try1 != 0);
	txantenna = params->ibp_pri >> 2;
	if (txantenna == 0)			/* XXX? */
		txantenna = sc->sc_txantenna;
	ctsduration = 0;
	if (flags & (HAL_TXDESC_CTSENA | HAL_TXDESC_RTSENA)) {
		cix = ath_tx_findrix(rt, params->ibp_ctsrate);
		ctsrate = rt->info[cix].rateCode;
		if (params->ibp_flags & IEEE80211_BPF_SHORTPRE) {
			ctsrate |= rt->info[cix].shortPreamble;
			if (flags & HAL_TXDESC_RTSENA)		/* SIFS + CTS */
				ctsduration += rt->info[cix].spAckDuration;
			ctsduration += ath_hal_computetxtime(ah,
				rt, pktlen, rix, AH_TRUE);
			if ((flags & HAL_TXDESC_NOACK) == 0)	/* SIFS + ACK */
				ctsduration += rt->info[rix].spAckDuration;
		} else {
			if (flags & HAL_TXDESC_RTSENA)		/* SIFS + CTS */
				ctsduration += rt->info[cix].lpAckDuration;
			ctsduration += ath_hal_computetxtime(ah,
				rt, pktlen, rix, AH_FALSE);
			if ((flags & HAL_TXDESC_NOACK) == 0)	/* SIFS + ACK */
				ctsduration += rt->info[rix].lpAckDuration;
		}
		ismrr = 0;			/* XXX */
	} else
		ctsrate = 0;
	pri = params->ibp_pri & 3;
	/*
	 * NB: we mark all packets as type PSPOLL so the h/w won't
	 * set the sequence number, duration, etc.
	 */
	atype = HAL_PKT_TYPE_PSPOLL;

	if (IFF_DUMPPKTS(sc, ATH_DEBUG_XMIT))
		ieee80211_dump_pkt(ic, mtod(m0, caddr_t), m0->m_len,
			sc->sc_hwmap[rix].ieeerate, -1);

	if (bpf_peers_present(ifp->if_bpf)) {
		u_int64_t tsf = ath_hal_gettsf64(ah);

		sc->sc_tx_th.wt_tsf = htole64(tsf);
		sc->sc_tx_th.wt_flags = sc->sc_hwmap[rix].txflags;
		if (wh->i_fc[1] & IEEE80211_FC1_WEP)
			sc->sc_tx_th.wt_flags |= IEEE80211_RADIOTAP_F_WEP;
		sc->sc_tx_th.wt_rate = sc->sc_hwmap[rix].ieeerate;
		sc->sc_tx_th.wt_txpower = ni->ni_txpower;
		sc->sc_tx_th.wt_antenna = sc->sc_txantenna;

		bpf_mtap2(ifp->if_bpf, &sc->sc_tx_th, sc->sc_tx_th_len, m0);
	}

	/*
	 * Formulate first tx descriptor with tx controls.
	 */
	ds = bf->bf_desc;
	/* XXX check return value? */
	ath_hal_setuptxdesc(ah, ds
		, pktlen		/* packet length */
		, hdrlen		/* header length */
		, atype			/* Atheros packet type */
		, params->ibp_power	/* txpower */
		, txrate, try0		/* series 0 rate/tries */
		, keyix			/* key cache index */
		, txantenna		/* antenna mode */
		, flags			/* flags */
		, ctsrate		/* rts/cts rate */
		, ctsduration		/* rts/cts duration */
	);
	bf->bf_txflags = flags;

	if (ismrr) {
		rix = ath_tx_findrix(rt, params->ibp_rate1);
		rate1 = rt->info[rix].rateCode;
		if (params->ibp_flags & IEEE80211_BPF_SHORTPRE)
			rate1 |= rt->info[rix].shortPreamble;
		if (params->ibp_try2) {
			rix = ath_tx_findrix(rt, params->ibp_rate2);
			rate2 = rt->info[rix].rateCode;
			if (params->ibp_flags & IEEE80211_BPF_SHORTPRE)
				rate2 |= rt->info[rix].shortPreamble;
		} else
			rate2 = 0;
		if (params->ibp_try3) {
			rix = ath_tx_findrix(rt, params->ibp_rate3);
			rate3 = rt->info[rix].rateCode;
			if (params->ibp_flags & IEEE80211_BPF_SHORTPRE)
				rate3 |= rt->info[rix].shortPreamble;
		} else
			rate3 = 0;
		ath_hal_setupxtxdesc(ah, ds
			, rate1, params->ibp_try1	/* series 1 */
			, rate2, params->ibp_try2	/* series 2 */
			, rate3, params->ibp_try3	/* series 3 */
		);
	}

	/* NB: no buffered multicast in power save support */
	ath_tx_handoff(sc, sc->sc_ac2q[pri], bf);
	return 0;
}

static int
ath_raw_xmit(struct ieee80211_node *ni, struct mbuf *m,
	const struct ieee80211_bpf_params *params)
{
	struct ieee80211com *ic = ni->ni_ic;
	struct ifnet *ifp = ic->ic_ifp;
	struct ath_softc *sc = ifp->if_softc;
	struct ath_buf *bf;

	if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0 || sc->sc_invalid) {
		DPRINTF(sc, ATH_DEBUG_XMIT, "%s: discard frame, %s", __func__,
		    (ifp->if_drv_flags & IFF_DRV_RUNNING) == 0 ?
			"!running" : "invalid");
		sc->sc_stats.ast_tx_raw_fail++;
		ieee80211_free_node(ni);
		m_freem(m);
		return ENETDOWN;
	}
	/*
	 * Grab a TX buffer and associated resources.
	 */
	bf = ath_getbuf(sc);
	if (bf == NULL) {
		/* NB: ath_getbuf handles stat+msg */
		ieee80211_free_node(ni);
		m_freem(m);
		return ENOBUFS;
	}

	ifp->if_opackets++;
	sc->sc_stats.ast_tx_raw++;

	if (params == NULL) {
		/*
		 * Legacy path; interpret frame contents to decide
		 * precisely how to send the frame.
		 */
		if (ath_tx_start(sc, ni, bf, m))
			goto bad;
	} else {
		/*
		 * Caller supplied explicit parameters to use in
		 * sending the frame.
		 */
		if (ath_tx_raw_start(sc, ni, bf, m, params))
			goto bad;
	}
	sc->sc_wd_timer = 5;

	return 0;
bad:
	ifp->if_oerrors++;
	ATH_TXBUF_LOCK(sc);
	STAILQ_INSERT_HEAD(&sc->sc_txbuf, bf, bf_list);
	ATH_TXBUF_UNLOCK(sc);
	ieee80211_free_node(ni);
	return EIO;		/* XXX */
}

/*
 * Announce various information on device/driver attach.
 */
static void
ath_announce(struct ath_softc *sc)
{
	struct ifnet *ifp = sc->sc_ifp;
	struct ath_hal *ah = sc->sc_ah;

	if_printf(ifp, "AR%s mac %d.%d RF%s phy %d.%d\n",
		ath_hal_mac_name(ah), ah->ah_macVersion, ah->ah_macRev,
		ath_hal_rf_name(ah), ah->ah_phyRev >> 4, ah->ah_phyRev & 0xf);
	if (bootverbose) {
		int i;
		for (i = 0; i <= WME_AC_VO; i++) {
			struct ath_txq *txq = sc->sc_ac2q[i];
			if_printf(ifp, "Use hw queue %u for %s traffic\n",
				txq->axq_qnum, ieee80211_wme_acnames[i]);
		}
		if_printf(ifp, "Use hw queue %u for CAB traffic\n",
			sc->sc_cabq->axq_qnum);
		if_printf(ifp, "Use hw queue %u for beacons\n", sc->sc_bhalq);
	}
	if (ath_rxbuf != ATH_RXBUF)
		if_printf(ifp, "using %u rx buffers\n", ath_rxbuf);
	if (ath_txbuf != ATH_TXBUF)
		if_printf(ifp, "using %u tx buffers\n", ath_txbuf);
}

#ifdef IEEE80211_SUPPORT_TDMA
static __inline uint32_t
ath_hal_getnexttbtt(struct ath_hal *ah)
{
#define	AR_TIMER0	0x8028
	return OS_REG_READ(ah, AR_TIMER0);
}

static __inline void
ath_hal_adjusttsf(struct ath_hal *ah, int32_t tsfdelta)
{
	/* XXX handle wrap/overflow */
	OS_REG_WRITE(ah, AR_TSF_L32, OS_REG_READ(ah, AR_TSF_L32) + tsfdelta);
}

static void
ath_tdma_settimers(struct ath_softc *sc, u_int32_t nexttbtt, u_int32_t bintval)
{
	struct ath_hal *ah = sc->sc_ah;
	HAL_BEACON_TIMERS bt;

	bt.bt_intval = bintval | HAL_BEACON_ENA;
	bt.bt_nexttbtt = nexttbtt;
	bt.bt_nextdba = (nexttbtt<<3) - sc->sc_tdmadbaprep;
	bt.bt_nextswba = (nexttbtt<<3) - sc->sc_tdmaswbaprep;
	bt.bt_nextatim = nexttbtt+1;
	ath_hal_beaconsettimers(ah, &bt);
}

/*
 * Calculate the beacon interval.  This is periodic in the
 * superframe for the bss.  We assume each station is configured
 * identically wrt transmit rate so the guard time we calculate
 * above will be the same on all stations.  Note we need to
 * factor in the xmit time because the hardware will schedule
 * a frame for transmit if the start of the frame is within
 * the burst time.  When we get hardware that properly kills
 * frames in the PCU we can reduce/eliminate the guard time.
 *
 * Roundup to 1024 is so we have 1 TU buffer in the guard time
 * to deal with the granularity of the nexttbtt timer.  11n MAC's
 * with 1us timer granularity should allow us to reduce/eliminate
 * this.
 */
static void
ath_tdma_bintvalsetup(struct ath_softc *sc,
	const struct ieee80211_tdma_state *tdma)
{
	/* copy from vap state (XXX check all vaps have same value?) */
	sc->sc_tdmaslotlen = tdma->tdma_slotlen;
	sc->sc_tdmabintcnt = tdma->tdma_bintval;

	sc->sc_tdmabintval = roundup((sc->sc_tdmaslotlen+sc->sc_tdmaguard) *
		tdma->tdma_slotcnt, 1024);
	sc->sc_tdmabintval >>= 10;		/* TSF -> TU */
	if (sc->sc_tdmabintval & 1)
		sc->sc_tdmabintval++;

	if (tdma->tdma_slot == 0) {
		/*
		 * Only slot 0 beacons; other slots respond.
		 */
		sc->sc_imask |= HAL_INT_SWBA;
		sc->sc_tdmaswba = 0;		/* beacon immediately */
	} else {
		/* XXX all vaps must be slot 0 or slot !0 */
		sc->sc_imask &= ~HAL_INT_SWBA;
	}
}

/*
 * Max 802.11 overhead.  This assumes no 4-address frames and
 * the encapsulation done by ieee80211_encap (llc).  We also
 * include potential crypto overhead.
 */
#define	IEEE80211_MAXOVERHEAD \
	(sizeof(struct ieee80211_qosframe) \
	 + sizeof(struct llc) \
	 + IEEE80211_ADDR_LEN \
	 + IEEE80211_WEP_IVLEN \
	 + IEEE80211_WEP_KIDLEN \
	 + IEEE80211_WEP_CRCLEN \
	 + IEEE80211_WEP_MICLEN \
	 + IEEE80211_CRC_LEN)

/*
 * Setup initially for tdma operation.  Start the beacon
 * timers and enable SWBA if we are slot 0.  Otherwise
 * we wait for slot 0 to arrive so we can sync up before
 * starting to transmit.
 */
static void
ath_tdma_config(struct ath_softc *sc, struct ieee80211vap *vap)
{
	struct ath_hal *ah = sc->sc_ah;
	struct ifnet *ifp = sc->sc_ifp;
	struct ieee80211com *ic = ifp->if_l2com;
	const struct ieee80211_txparam *tp;
	const struct ieee80211_tdma_state *tdma = NULL;
	int rix;

	if (vap == NULL) {
		vap = TAILQ_FIRST(&ic->ic_vaps);   /* XXX */
		if (vap == NULL) {
			if_printf(ifp, "%s: no vaps?\n", __func__);
			return;
		}
	}
	tp = vap->iv_bss->ni_txparms;
	/*
	 * Calculate the guard time for each slot.  This is the
	 * time to send a maximal-size frame according to the
	 * fixed/lowest transmit rate.  Note that the interface
	 * mtu does not include the 802.11 overhead so we must
	 * tack that on (ath_hal_computetxtime includes the
	 * preamble and plcp in it's calculation).
	 */
	tdma = vap->iv_tdma;
	if (tp->ucastrate != IEEE80211_FIXED_RATE_NONE)
		rix = ath_tx_findrix(sc->sc_currates, tp->ucastrate);
	else
		rix = ath_tx_findrix(sc->sc_currates, tp->mcastrate);
	/* XXX short preamble assumed */
	sc->sc_tdmaguard = ath_hal_computetxtime(ah, sc->sc_currates,
		ifp->if_mtu + IEEE80211_MAXOVERHEAD, rix, AH_TRUE);

	ath_hal_intrset(ah, 0);

	ath_beaconq_config(sc);			/* setup h/w beacon q */
	if (sc->sc_setcca)
		ath_hal_setcca(ah, AH_FALSE);	/* disable CCA */
	ath_tdma_bintvalsetup(sc, tdma);	/* calculate beacon interval */
	ath_tdma_settimers(sc, sc->sc_tdmabintval,
		sc->sc_tdmabintval | HAL_BEACON_RESET_TSF);
	sc->sc_syncbeacon = 0;

	sc->sc_avgtsfdeltap = TDMA_DUMMY_MARKER;
	sc->sc_avgtsfdeltam = TDMA_DUMMY_MARKER;

	ath_hal_intrset(ah, sc->sc_imask);

	DPRINTF(sc, ATH_DEBUG_TDMA, "%s: slot %u len %uus cnt %u "
	    "bsched %u guard %uus bintval %u TU dba prep %u\n", __func__,
	    tdma->tdma_slot, tdma->tdma_slotlen, tdma->tdma_slotcnt,
	    tdma->tdma_bintval, sc->sc_tdmaguard, sc->sc_tdmabintval,
	    sc->sc_tdmadbaprep);
}

/*
 * Update tdma operation.  Called from the 802.11 layer
 * when a beacon is received from the TDMA station operating
 * in the slot immediately preceding us in the bss.  Use
 * the rx timestamp for the beacon frame to update our
 * beacon timers so we follow their schedule.  Note that
 * by using the rx timestamp we implicitly include the
 * propagation delay in our schedule.
 */
static void
ath_tdma_update(struct ieee80211_node *ni,
	const struct ieee80211_tdma_param *tdma, int changed)
{
#define	TSF_TO_TU(_h,_l) \
	((((u_int32_t)(_h)) << 22) | (((u_int32_t)(_l)) >> 10))
#define	TU_TO_TSF(_tu)	(((u_int64_t)(_tu)) << 10)
	struct ieee80211vap *vap = ni->ni_vap;
	struct ieee80211com *ic = ni->ni_ic;
	struct ath_softc *sc = ic->ic_ifp->if_softc;
	struct ath_hal *ah = sc->sc_ah;
	const HAL_RATE_TABLE *rt = sc->sc_currates;
	u_int64_t tsf, rstamp, nextslot;
	u_int32_t txtime, nextslottu, timer0;
	int32_t tudelta, tsfdelta;
	const struct ath_rx_status *rs;
	int rix;

	sc->sc_stats.ast_tdma_update++;

	/*
	 * Check for and adopt configuration changes.
	 */
	if (changed != 0) {
		const struct ieee80211_tdma_state *ts = vap->iv_tdma;

		ath_tdma_bintvalsetup(sc, ts);

		DPRINTF(sc, ATH_DEBUG_TDMA,
		    "%s: adopt slot %u slotcnt %u slotlen %u us "
		    "bintval %u TU\n", __func__,
		    ts->tdma_slot, ts->tdma_slotcnt, ts->tdma_slotlen,
		    sc->sc_tdmabintval);

		ath_beaconq_config(sc);
		/* XXX right? */
		ath_hal_intrset(ah, sc->sc_imask);
		/* NB: beacon timers programmed below */
	}

	/* extend rx timestamp to 64 bits */
	tsf = ath_hal_gettsf64(ah);
	rstamp = ath_extend_tsf(ni->ni_rstamp, tsf);
	/*
	 * The rx timestamp is set by the hardware on completing
	 * reception (at the point where the rx descriptor is DMA'd
	 * to the host).  To find the start of our next slot we
	 * must adjust this time by the time required to send
	 * the packet just received.
	 */
	rs = sc->sc_tdmars;
	rix = rt->rateCodeToIndex[rs->rs_rate];
	txtime = ath_hal_computetxtime(ah, rt, rs->rs_datalen, rix,
	    rt->info[rix].shortPreamble);
	/* NB: << 9 is to cvt to TU and /2 */
	nextslot = (rstamp - txtime) + (sc->sc_tdmabintval << 9);
	nextslottu = TSF_TO_TU(nextslot>>32, nextslot) & HAL_BEACON_PERIOD;

	/*
	 * TIMER0 is the h/w's idea of NextTBTT (in TU's).  Convert
	 * to usecs and calculate the difference between what the
	 * other station thinks and what we have programmed.  This
	 * lets us figure how to adjust our timers to match.  The
	 * adjustments are done by pulling the TSF forward and possibly
	 * rewriting the beacon timers.
	 */
	timer0 = ath_hal_getnexttbtt(ah);
	tsfdelta = (int32_t)((nextslot % TU_TO_TSF(HAL_BEACON_PERIOD+1)) - TU_TO_TSF(timer0));

	DPRINTF(sc, ATH_DEBUG_TDMA_TIMER,
	    "tsfdelta %d avg +%d/-%d\n", tsfdelta,
	    TDMA_AVG(sc->sc_avgtsfdeltap), TDMA_AVG(sc->sc_avgtsfdeltam));

	if (tsfdelta < 0) {
		TDMA_SAMPLE(sc->sc_avgtsfdeltap, 0);
		TDMA_SAMPLE(sc->sc_avgtsfdeltam, -tsfdelta);
		tsfdelta = -tsfdelta % 1024;
		nextslottu++;
	} else if (tsfdelta > 0) {
		TDMA_SAMPLE(sc->sc_avgtsfdeltap, tsfdelta);
		TDMA_SAMPLE(sc->sc_avgtsfdeltam, 0);
		tsfdelta = 1024 - (tsfdelta % 1024);
		nextslottu++;
	} else {
		TDMA_SAMPLE(sc->sc_avgtsfdeltap, 0);
		TDMA_SAMPLE(sc->sc_avgtsfdeltam, 0);
	}
	tudelta = nextslottu - timer0;

	/*
	 * Copy sender's timetstamp into tdma ie so they can
	 * calculate roundtrip time.  We submit a beacon frame
	 * below after any timer adjustment.  The frame goes out
	 * at the next TBTT so the sender can calculate the
	 * roundtrip by inspecting the tdma ie in our beacon frame.
	 *
	 * NB: This tstamp is subtlely preserved when
	 *     IEEE80211_BEACON_TDMA is marked (e.g. when the
	 *     slot position changes) because ieee80211_add_tdma
	 *     skips over the data.
	 */
	memcpy(ATH_VAP(vap)->av_boff.bo_tdma +
		__offsetof(struct ieee80211_tdma_param, tdma_tstamp),
		&ni->ni_tstamp.data, 8);
#if 0
	DPRINTF(sc, ATH_DEBUG_TDMA_TIMER,
	    "tsf %llu nextslot %llu (%d, %d) nextslottu %u timer0 %u (%d)\n",
	    (unsigned long long) tsf, (unsigned long long) nextslot,
	    (int)(nextslot - tsf), tsfdelta,
	    nextslottu, timer0, tudelta);
#endif
	/*
	 * Adjust the beacon timers only when pulling them forward
	 * or when going back by less than the beacon interval.
	 * Negative jumps larger than the beacon interval seem to
	 * cause the timers to stop and generally cause instability.
	 * This basically filters out jumps due to missed beacons.
	 */
	if (tudelta != 0 && (tudelta > 0 || -tudelta < sc->sc_tdmabintval)) {
		ath_tdma_settimers(sc, nextslottu, sc->sc_tdmabintval);
		sc->sc_stats.ast_tdma_timers++;
	}
	if (tsfdelta > 0) {
		ath_hal_adjusttsf(ah, tsfdelta);
		sc->sc_stats.ast_tdma_tsf++;
	}
	ath_tdma_beacon_send(sc, vap);		/* prepare response */
#undef TU_TO_TSF
#undef TSF_TO_TU
}

/*
 * Transmit a beacon frame at SWBA.  Dynamic updates
 * to the frame contents are done as needed.
 */
static void
ath_tdma_beacon_send(struct ath_softc *sc, struct ieee80211vap *vap)
{
	struct ath_hal *ah = sc->sc_ah;
	struct ath_buf *bf;
	int otherant;

	/*
	 * Check if the previous beacon has gone out.  If
	 * not don't try to post another, skip this period
	 * and wait for the next.  Missed beacons indicate
	 * a problem and should not occur.  If we miss too
	 * many consecutive beacons reset the device.
	 */
	if (ath_hal_numtxpending(ah, sc->sc_bhalq) != 0) {
		sc->sc_bmisscount++;
		DPRINTF(sc, ATH_DEBUG_BEACON,
			"%s: missed %u consecutive beacons\n",
			__func__, sc->sc_bmisscount);
		if (sc->sc_bmisscount >= ath_bstuck_threshold)
			taskqueue_enqueue(sc->sc_tq, &sc->sc_bstucktask);
		return;
	}
	if (sc->sc_bmisscount != 0) {
		DPRINTF(sc, ATH_DEBUG_BEACON,
			"%s: resume beacon xmit after %u misses\n",
			__func__, sc->sc_bmisscount);
		sc->sc_bmisscount = 0;
	}

	/*
	 * Check recent per-antenna transmit statistics and flip
	 * the default antenna if noticeably more frames went out
	 * on the non-default antenna.
	 * XXX assumes 2 anntenae
	 */
	if (!sc->sc_diversity) {
		otherant = sc->sc_defant & 1 ? 2 : 1;
		if (sc->sc_ant_tx[otherant] > sc->sc_ant_tx[sc->sc_defant] + 2)
			ath_setdefantenna(sc, otherant);
		sc->sc_ant_tx[1] = sc->sc_ant_tx[2] = 0;
	}

	bf = ath_beacon_generate(sc, vap);
	if (bf != NULL) {
		/*
		 * Stop any current dma and put the new frame on the queue.
		 * This should never fail since we check above that no frames
		 * are still pending on the queue.
		 */
		if (!ath_hal_stoptxdma(ah, sc->sc_bhalq)) {
			DPRINTF(sc, ATH_DEBUG_ANY,
				"%s: beacon queue %u did not stop?\n",
				__func__, sc->sc_bhalq);
			/* NB: the HAL still stops DMA, so proceed */
		}
		ath_hal_puttxbuf(ah, sc->sc_bhalq, bf->bf_daddr);
		ath_hal_txstart(ah, sc->sc_bhalq);

		sc->sc_stats.ast_be_xmit++;		/* XXX per-vap? */

		/*
		 * Record local TSF for our last send for use
		 * in arbitrating slot collisions.
		 */
		vap->iv_bss->ni_tstamp.tsf = ath_hal_gettsf64(ah);
	}
}
#endif /* IEEE80211_SUPPORT_TDMA */