ath9k: work around false-positive gcc warning

gcc-10 shows a false-positive warning with CONFIG_KASAN:

drivers/net/wireless/ath/ath9k/dynack.c: In function 'ath_dynack_sample_tx_ts':
include/linux/etherdevice.h:290:14: warning: writing 4 bytes into a region of size 0 [-Wstringop-overflow=]
290 | *(u32 *)dst = *(const u32 *)src;
| ~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~

Until gcc is fixed, work around this by using memcpy() in place
of ether_addr_copy(). Hopefully gcc-11 will not have this problem.

Link: https://godbolt.org/z/sab1MK
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97490
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
[kvalo@codeaurora.org: remove ifdef and add a comment]
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20201026213040.3889546-8-arnd@kernel.org

ath9k: dynack: Demote non-compliant function header

Fixes the following W=1 kernel build warning(s):

drivers/net/wireless/ath/ath9k/dynack.c:52: warning: Function parameter or member 'old' not described in 'ath_dynack_ewma'
drivers/net/wireless/ath/ath9k/dynack.c:52: warning: Function parameter or member 'new' not described in 'ath_dynack_ewma'

Cc: QCA ath9k Development <ath9k-devel@qca.qualcomm.com>
Cc: Kalle Valo <kvalo@codeaurora.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>
Cc: linux-wireless@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20201102112410.1049272-40-lee.jones@linaro.org

ath9k: dynack: set ackto to max timeout in ath_dynack_reset

Initialize acktimeout to the maximum configurable value in
ath_dynack_reset in order to not disconnect long distance static links
enabling dynack and even to take care of possible errors configuring
a static timeout. Moreover initialize station timeout value to the current
acktimeout value

Tested-by: Koen Vandeputte <koen.vandeputte@ncentric.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath9k: dynack: set max timeout according to channel width

Compute maximum configurable ackimeout/ctstimeout according to channel
width (clockrate)

Tested-by: Koen Vandeputte <koen.vandeputte@ncentric.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath9k: dynack: properly set last timeout timestamp in ath_dynack_reset

Add compute timeout to last computation timestamp in
ath_dynack_reset in order to not run ath_dynack_compute_ackto
immediately

Tested-by: Koen Vandeputte <koen.vandeputte@ncentric.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath9k: dyanck: introduce ath_dynack_set_timeout routine

Introduce ath_dynack_set_timeout routine to configure slottime/ack/cts
timeouts and remove duplicated code

Tested-by: Koen Vandeputte <koen.vandeputte@ncentric.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath9k: dynack: fix possible deadlock in ath_dynack_node_{de}init

Fix following lockdep warning disabling bh in
ath_dynack_node_init/ath_dynack_node_deinit

[ 75.955878] --------------------------------
[ 75.955880] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
[ 75.955884] swapper/0/0 [HC0[0]:SC1[3]:HE1:SE0] takes:
[ 75.955888] 00000000792a7ee0 (&(&da->qlock)->rlock){+.?.}, at: ath_dynack_sample_ack_ts+0x4d/0xa0 [ath9k_hw]
[ 75.955905] {SOFTIRQ-ON-W} state was registered at:
[ 75.955912] lock_acquire+0x9a/0x160
[ 75.955917] _raw_spin_lock+0x2c/0x70
[ 75.955927] ath_dynack_node_init+0x2a/0x60 [ath9k_hw]
[ 75.955934] ath9k_sta_state+0xec/0x160 [ath9k]
[ 75.955976] drv_sta_state+0xb2/0x740 [mac80211]
[ 75.956008] sta_info_insert_finish+0x21a/0x420 [mac80211]
[ 75.956039] sta_info_insert_rcu+0x12b/0x2c0 [mac80211]
[ 75.956069] sta_info_insert+0x7/0x70 [mac80211]
[ 75.956093] ieee80211_prep_connection+0x42e/0x730 [mac80211]
[ 75.956120] ieee80211_mgd_auth.cold+0xb9/0x15c [mac80211]
[ 75.956152] cfg80211_mlme_auth+0x143/0x350 [cfg80211]
[ 75.956169] nl80211_authenticate+0x25e/0x2b0 [cfg80211]
[ 75.956172] genl_family_rcv_msg+0x198/0x400
[ 75.956174] genl_rcv_msg+0x42/0x90
[ 75.956176] netlink_rcv_skb+0x35/0xf0
[ 75.956178] genl_rcv+0x1f/0x30
[ 75.956180] netlink_unicast+0x154/0x200
[ 75.956182] netlink_sendmsg+0x1bf/0x3d0
[ 75.956186] ___sys_sendmsg+0x2c2/0x2f0
[ 75.956187] __sys_sendmsg+0x44/0x80
[ 75.956190] do_syscall_64+0x55/0x1a0
[ 75.956192] entry_SYSCALL_64_after_hwframe+0x49/0xbe
[ 75.956194] irq event stamp: 2357092
[ 75.956196] hardirqs last enabled at (2357092): [<ffffffff818c62de>] _raw_spin_unlock_irqrestore+0x3e/0x50
[ 75.956199] hardirqs last disabled at (2357091): [<ffffffff818c60b1>] _raw_spin_lock_irqsave+0x11/0x80
[ 75.956202] softirqs last enabled at (2357072): [<ffffffff8106dc09>] irq_enter+0x59/0x60
[ 75.956204] softirqs last disabled at (2357073): [<ffffffff8106dcbe>] irq_exit+0xae/0xc0
[ 75.956206]
other info that might help us debug this:
[ 75.956207] Possible unsafe locking scenario:

[ 75.956208] CPU0
[ 75.956209] ----
[ 75.956210] lock(&(&da->qlock)->rlock);
[ 75.956213] <Interrupt>
[ 75.956214] lock(&(&da->qlock)->rlock);
[ 75.956216]
*** DEADLOCK ***

[ 75.956217] 1 lock held by swapper/0/0:
[ 75.956219] #0: 000000003bb5675c (&(&sc->sc_pcu_lock)->rlock){+.-.}, at: ath9k_tasklet+0x55/0x240 [ath9k]
[ 75.956225]
stack backtrace:
[ 75.956228] CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.3.0-rc1-wdn+ #13
[ 75.956229] Hardware name: Dell Inc. Studio XPS 1340/0K183D, BIOS A11 09/08/2009
[ 75.956231] Call Trace:
[ 75.956233] <IRQ>
[ 75.956236] dump_stack+0x67/0x90
[ 75.956239] mark_lock+0x4c1/0x640
[ 75.956242] ? check_usage_backwards+0x130/0x130
[ 75.956245] ? sched_clock_local+0x12/0x80
[ 75.956247] __lock_acquire+0x484/0x7a0
[ 75.956250] ? __lock_acquire+0x3b9/0x7a0
[ 75.956252] lock_acquire+0x9a/0x160
[ 75.956259] ? ath_dynack_sample_ack_ts+0x4d/0xa0 [ath9k_hw]
[ 75.956262] _raw_spin_lock_bh+0x34/0x80
[ 75.956268] ? ath_dynack_sample_ack_ts+0x4d/0xa0 [ath9k_hw]
[ 75.956275] ath_dynack_sample_ack_ts+0x4d/0xa0 [ath9k_hw]
[ 75.956280] ath_rx_tasklet+0xd09/0xe90 [ath9k]
[ 75.956286] ath9k_tasklet+0x102/0x240 [ath9k]
[ 75.956288] tasklet_action_common.isra.0+0x6d/0x170
[ 75.956291] __do_softirq+0xcc/0x425
[ 75.956294] irq_exit+0xae/0xc0
[ 75.956296] do_IRQ+0x8a/0x110
[ 75.956298] common_interrupt+0xf/0xf
[ 75.956300] </IRQ>
[ 75.956303] RIP: 0010:cpuidle_enter_state+0xb2/0x400
[ 75.956308] RSP: 0018:ffffffff82203e70 EFLAGS: 00000202 ORIG_RAX: ffffffffffffffd7
[ 75.956310] RAX: ffffffff82219800 RBX: ffffffff822bd0a0 RCX: 0000000000000000
[ 75.956312] RDX: 0000000000000046 RSI: 0000000000000006 RDI: ffffffff82219800
[ 75.956314] RBP: ffff888155a01c00 R08: 00000011af51aabe R09: 0000000000000000
[ 75.956315] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000002
[ 75.956317] R13: 00000011af51aabe R14: 0000000000000003 R15: ffffffff82219800
[ 75.956321] cpuidle_enter+0x24/0x40
[ 75.956323] do_idle+0x1ac/0x220
[ 75.956326] cpu_startup_entry+0x14/0x20
[ 75.956329] start_kernel+0x482/0x489
[ 75.956332] secondary_startup_64+0xa4/0xb0

Fixes: c774d57fd47c ("ath9k: add dynamic ACK timeout estimation")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Tested-by: Koen Vandeputte <koen.vandeputte@ncentric.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath9k: dynack: make ewma estimation faster

In order to make propagation time estimation faster,
use current sample as ewma output value during 'late ack'
tracking

Tested-by: Koen Vandeputte <koen.vandeputte@ncentric.com>
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath9k: dynack: check da->enabled first in sampling routines

Check da->enabled flag first in ath_dynack_sample_tx_ts and
ath_dynack_sample_ack_ts routines in order to avoid useless
processing

Tested-by: Koen Vandeputte <koen.vandeputte@ncentric.com>
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath9k: dynack: move debug log after buffer increments

Move debug log in ath_dynack_sample_tx_ts and ath_dynack_sample_ack_ts
after timestamp buffer head/tail increments in order to make debugging
more user friendly

Tested-by: Koen Vandeputte <koen.vandeputte@ncentric.com>
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath9k: dynack: use authentication messages for 'late' ack

In order to properly support dynack in ad-hoc mode running
wpa_supplicant, take into account authentication frames for
'late ack' detection. This patch has been tested on devices
mounted on offshore high-voltage stations connected through
~24Km link

Reported-by: Koen Vandeputte <koen.vandeputte@ncentric.com>
Tested-by: Koen Vandeputte <koen.vandeputte@ncentric.com>
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

ath9k: Remove some #defined constants to decrease verbosity

The removed ATH9K_SLOT_TIME_X constants simply map the value in microseconds
to the same integer. These constants were not used consistently, so fix the
inconsistency issue by replacing all occurances with the integer equivalent.

Signed-off-by: Benjamin Berg <benjamin.berg@open-mesh.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

cfg80211: remove enum ieee80211_band

This enum is already perfectly aliased to enum nl80211_band, and
the only reason for it is that we get IEEE80211_NUM_BANDS out of
it. There's no really good reason to not declare the number of
bands in nl80211 though, so do that and remove the cfg80211 one.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

ath9k: fix getting tx duration for dynack

On AR9003, tx control and tx status are in separate descriptor rings.
Tx duration is extracted from the tx control descriptor data, which
ar9003_hw_proc_txdesc cannot access.

Fix getting the duration by adding a separate callback for it.

Acked-by: Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

ath9k: add dynamic ACK timeout estimation

Add dynamic ACK timeout estimation algorithm based on ACK frame RX timestamp,
TX frame timestamp and frame duration.

Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>
Tested-by: Philippe Duchein <wireless-dev@duchein.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>