1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2007-2008 Sam Leffler, Errno Consulting
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28#ifndef _NET80211_IEEE80211_PHY_H_
29#define _NET80211_IEEE80211_PHY_H_
30
31#ifdef _KERNEL
32/*
33 * IEEE 802.11 PHY-related definitions.
34 */
35
36/*
37 * Contention window (slots).
38 */
39#define IEEE80211_CW_MAX	1023	/* aCWmax */
40#define IEEE80211_CW_MIN_0	31	/* DS/CCK aCWmin, ERP aCWmin(0) */
41#define IEEE80211_CW_MIN_1	15	/* OFDM aCWmin, ERP aCWmin(1) */
42
43/*
44 * SIFS (microseconds).
45 */
46#define IEEE80211_DUR_SIFS	10	/* DS/CCK/ERP SIFS */
47#define IEEE80211_DUR_OFDM_SIFS	16	/* OFDM SIFS */
48
49/*
50 * Slot time (microseconds).
51 */
52#define IEEE80211_DUR_SLOT	20	/* DS/CCK slottime, ERP long slottime */
53#define IEEE80211_DUR_SHSLOT	9	/* ERP short slottime */
54#define IEEE80211_DUR_OFDM_SLOT	9	/* OFDM slottime */
55
56/*
57 * For drivers that don't implement per-VAP slot time
58 * (ie, they rely on net80211 figuring out the union
59 * between VAPs to program a single radio) - return
60 * the current radio configured slot time.
61 */
62#define IEEE80211_GET_SLOTTIME(ic) \
63	((ic->ic_flags & IEEE80211_F_SHSLOT) ? \
64	    IEEE80211_DUR_SHSLOT : IEEE80211_DUR_SLOT)
65
66/*
67 * For drivers that implement per-VAP slot time; look
68 * at the per-VAP flags to determine whether this VAP
69 * is in short or long slot time.
70 */
71#define IEEE80211_VAP_GET_SLOTTIME(vap) \
72	((vap->iv_flags & IEEE80211_F_SHSLOT) ? \
73	    IEEE80211_DUR_SHSLOT : IEEE80211_DUR_SLOT)
74
75/*
76 * DIFS (microseconds).
77 */
78#define IEEE80211_DUR_DIFS(sifs, slot)	((sifs) + 2 * (slot))
79
80struct ieee80211_channel;
81
82#define	IEEE80211_RATE_TABLE_SIZE	128
83
84struct ieee80211_rate_table {
85	int		rateCount;		/* NB: for proper padding */
86	uint8_t		rateCodeToIndex[256];	/* back mapping */
87	struct {
88		uint8_t		phy;		/* CCK/OFDM/TURBO */
89		uint32_t	rateKbps;	/* transfer rate in kbs */
90		uint8_t		shortPreamble;	/* mask for enabling short
91						 * preamble in CCK rate code */
92		uint8_t		dot11Rate;	/* value for supported rates
93						 * info element of MLME */
94		uint8_t		ctlRateIndex;	/* index of next lower basic
95						 * rate; used for dur. calcs */
96		uint16_t	lpAckDuration;	/* long preamble ACK dur. */
97		uint16_t	spAckDuration;	/* short preamble ACK dur. */
98	} info[IEEE80211_RATE_TABLE_SIZE];
99};
100
101const struct ieee80211_rate_table *ieee80211_get_ratetable(
102			struct ieee80211_channel *);
103
104static __inline__ uint8_t
105ieee80211_ack_rate(const struct ieee80211_rate_table *rt, uint8_t rate)
106{
107	/*
108	 * XXX Assert this is for a legacy rate; not for an MCS rate.
109	 * If the caller wishes to use it for a basic rate, they should
110	 * clear the high bit first.
111	 */
112	KASSERT(! (rate & 0x80), ("rate %d is basic/mcs?", rate));
113
114	uint8_t cix = rt->info[rt->rateCodeToIndex[rate & IEEE80211_RATE_VAL]].ctlRateIndex;
115	KASSERT(cix != (uint8_t)-1, ("rate %d has no info", rate));
116	return rt->info[cix].dot11Rate;
117}
118
119static __inline__ uint8_t
120ieee80211_ctl_rate(const struct ieee80211_rate_table *rt, uint8_t rate)
121{
122	/*
123	 * XXX Assert this is for a legacy rate; not for an MCS rate.
124	 * If the caller wishes to use it for a basic rate, they should
125	 * clear the high bit first.
126	 */
127	KASSERT(! (rate & 0x80), ("rate %d is basic/mcs?", rate));
128
129	uint8_t cix = rt->info[rt->rateCodeToIndex[rate & IEEE80211_RATE_VAL]].ctlRateIndex;
130	KASSERT(cix != (uint8_t)-1, ("rate %d has no info", rate));
131	return rt->info[cix].dot11Rate;
132}
133
134static __inline__ enum ieee80211_phytype
135ieee80211_rate2phytype(const struct ieee80211_rate_table *rt, uint8_t rate)
136{
137	/*
138	 * XXX Assert this is for a legacy rate; not for an MCS rate.
139	 * If the caller wishes to use it for a basic rate, they should
140	 * clear the high bit first.
141	 */
142	KASSERT(! (rate & 0x80), ("rate %d is basic/mcs?", rate));
143
144	uint8_t rix = rt->rateCodeToIndex[rate & IEEE80211_RATE_VAL];
145	KASSERT(rix != (uint8_t)-1, ("rate %d has no info", rate));
146	return rt->info[rix].phy;
147}
148
149static __inline__ int
150ieee80211_isratevalid(const struct ieee80211_rate_table *rt, uint8_t rate)
151{
152	/*
153	 * XXX Assert this is for a legacy rate; not for an MCS rate.
154	 * If the caller wishes to use it for a basic rate, they should
155	 * clear the high bit first.
156	 */
157	KASSERT(! (rate & 0x80), ("rate %d is basic/mcs?", rate));
158
159	return rt->rateCodeToIndex[rate] != (uint8_t)-1;
160}
161
162/*
163 * Calculate ACK field for
164 * o  non-fragment data frames
165 * o  management frames
166 * sent using rate, phy and short preamble setting.
167 */
168static __inline__ uint16_t
169ieee80211_ack_duration(const struct ieee80211_rate_table *rt,
170    uint8_t rate, int isShortPreamble)
171{
172	uint8_t rix = rt->rateCodeToIndex[rate];
173
174	KASSERT(rix != (uint8_t)-1, ("rate %d has no info", rate));
175	if (isShortPreamble) {
176		KASSERT(rt->info[rix].spAckDuration != 0,
177			("shpreamble ack dur is not computed!\n"));
178		return rt->info[rix].spAckDuration;
179	} else {
180		KASSERT(rt->info[rix].lpAckDuration != 0,
181			("lgpreamble ack dur is not computed!\n"));
182		return rt->info[rix].lpAckDuration;
183	}
184}
185
186static __inline__ uint8_t
187ieee80211_legacy_rate_lookup(const struct ieee80211_rate_table *rt,
188    uint8_t rate)
189{
190
191	return (rt->rateCodeToIndex[rate & IEEE80211_RATE_VAL]);
192}
193
194/*
195 * Compute the time to transmit a frame of length frameLen bytes
196 * using the specified 802.11 rate code, phy, and short preamble
197 * setting.
198 *
199 * NB: SIFS is included.
200 */
201uint16_t	ieee80211_compute_duration(const struct ieee80211_rate_table *,
202			uint32_t frameLen, uint16_t rate, int isShortPreamble);
203/*
204 * Convert PLCP signal/rate field to 802.11 rate code (.5Mbits/s)
205 */
206uint8_t		ieee80211_plcp2rate(uint8_t, enum ieee80211_phytype);
207/*
208 * Convert 802.11 rate code to PLCP signal.
209 */
210uint8_t		ieee80211_rate2plcp(int, enum ieee80211_phytype);
211
212/*
213 * 802.11n rate manipulation.
214 */
215
216#define	IEEE80211_HT_RC_2_MCS(_rc)	((_rc) & 0x1f)
217#define	IEEE80211_HT_RC_2_STREAMS(_rc)	((((_rc) & 0x78) >> 3) + 1)
218#define	IEEE80211_IS_HT_RATE(_rc)		( (_rc) & IEEE80211_RATE_MCS)
219
220uint32_t	ieee80211_compute_duration_ht(uint32_t frameLen,
221			uint16_t rate, int streams, int isht40,
222			int isShortGI);
223
224#endif	/* _KERNEL */
225#endif	/* !_NET80211_IEEE80211_PHY_H_ */
226