1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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 * $FreeBSD: releng/12.0/sys/net80211/ieee80211_phy.h 326272 2017-11-27 15:23:17Z pfg $
28 */
29
30#ifndef _NET80211_IEEE80211_PHY_H_
31#define _NET80211_IEEE80211_PHY_H_
32
33#ifdef _KERNEL
34/*
35 * IEEE 802.11 PHY-related definitions.
36 */
37
38/*
39 * Contention window (slots).
40 */
41#define IEEE80211_CW_MAX	1023	/* aCWmax */
42#define IEEE80211_CW_MIN_0	31	/* DS/CCK aCWmin, ERP aCWmin(0) */
43#define IEEE80211_CW_MIN_1	15	/* OFDM aCWmin, ERP aCWmin(1) */
44
45/*
46 * SIFS (microseconds).
47 */
48#define IEEE80211_DUR_SIFS	10	/* DS/CCK/ERP SIFS */
49#define IEEE80211_DUR_OFDM_SIFS	16	/* OFDM SIFS */
50
51/*
52 * Slot time (microseconds).
53 */
54#define IEEE80211_DUR_SLOT	20	/* DS/CCK slottime, ERP long slottime */
55#define IEEE80211_DUR_SHSLOT	9	/* ERP short slottime */
56#define IEEE80211_DUR_OFDM_SLOT	9	/* OFDM slottime */
57
58/*
59 * For drivers that don't implement per-VAP slot time
60 * (ie, they rely on net80211 figuring out the union
61 * between VAPs to program a single radio) - return
62 * the current radio configured slot time.
63 */
64#define IEEE80211_GET_SLOTTIME(ic) \
65	((ic->ic_flags & IEEE80211_F_SHSLOT) ? \
66	    IEEE80211_DUR_SHSLOT : IEEE80211_DUR_SLOT)
67
68/*
69 * For drivers that implement per-VAP slot time; look
70 * at the per-VAP flags to determine whether this VAP
71 * is in short or long slot time.
72 */
73#define IEEE80211_VAP_GET_SLOTTIME(vap) \
74	((vap->iv_flags & IEEE80211_F_SHSLOT) ? \
75	    IEEE80211_DUR_SHSLOT : IEEE80211_DUR_SLOT)
76
77/*
78 * DIFS (microseconds).
79 */
80#define IEEE80211_DUR_DIFS(sifs, slot)	((sifs) + 2 * (slot))
81
82struct ieee80211_channel;
83
84#define	IEEE80211_RATE_TABLE_SIZE	128
85
86struct ieee80211_rate_table {
87	int		rateCount;		/* NB: for proper padding */
88	uint8_t		rateCodeToIndex[256];	/* back mapping */
89	struct {
90		uint8_t		phy;		/* CCK/OFDM/TURBO */
91		uint32_t	rateKbps;	/* transfer rate in kbs */
92		uint8_t		shortPreamble;	/* mask for enabling short
93						 * preamble in CCK rate code */
94		uint8_t		dot11Rate;	/* value for supported rates
95						 * info element of MLME */
96		uint8_t		ctlRateIndex;	/* index of next lower basic
97						 * rate; used for dur. calcs */
98		uint16_t	lpAckDuration;	/* long preamble ACK dur. */
99		uint16_t	spAckDuration;	/* short preamble ACK dur. */
100	} info[IEEE80211_RATE_TABLE_SIZE];
101};
102
103const struct ieee80211_rate_table *ieee80211_get_ratetable(
104			struct ieee80211_channel *);
105
106static __inline__ uint8_t
107ieee80211_ack_rate(const struct ieee80211_rate_table *rt, uint8_t rate)
108{
109	uint8_t cix;
110	/*
111	 * XXX Assert this is for a legacy rate; not for an MCS rate.
112	 * If the caller wishes to use it for a basic rate, they should
113	 * clear the high bit first.
114	 */
115	KASSERT(! (rate & 0x80), ("rate %d is basic/mcs?", rate));
116
117	cix = rt->info[rt->rateCodeToIndex[rate & IEEE80211_RATE_VAL]].ctlRateIndex;
118	KASSERT(cix != (uint8_t)-1, ("rate %d has no info", rate));
119	return rt->info[cix].dot11Rate;
120}
121
122static __inline__ uint8_t
123ieee80211_ctl_rate(const struct ieee80211_rate_table *rt, uint8_t rate)
124{
125	uint8_t cix;
126	/*
127	 * XXX Assert this is for a legacy rate; not for an MCS rate.
128	 * If the caller wishes to use it for a basic rate, they should
129	 * clear the high bit first.
130	 */
131	KASSERT(! (rate & 0x80), ("rate %d is basic/mcs?", rate));
132
133	cix = rt->info[rt->rateCodeToIndex[rate & IEEE80211_RATE_VAL]].ctlRateIndex;
134	KASSERT(cix != (uint8_t)-1, ("rate %d has no info", rate));
135	return rt->info[cix].dot11Rate;
136}
137
138static __inline__ enum ieee80211_phytype
139ieee80211_rate2phytype(const struct ieee80211_rate_table *rt, uint8_t rate)
140{
141	uint8_t rix;
142	/*
143	 * XXX Assert this is for a legacy rate; not for an MCS rate.
144	 * If the caller wishes to use it for a basic rate, they should
145	 * clear the high bit first.
146	 */
147	KASSERT(! (rate & 0x80), ("rate %d is basic/mcs?", rate));
148
149	rix = rt->rateCodeToIndex[rate & IEEE80211_RATE_VAL];
150	KASSERT(rix != (uint8_t)-1, ("rate %d has no info", rate));
151	return (enum ieee80211_phytype)rt->info[rix].phy;
152}
153
154static __inline__ int
155ieee80211_isratevalid(const struct ieee80211_rate_table *rt, uint8_t rate)
156{
157	/*
158	 * XXX Assert this is for a legacy rate; not for an MCS rate.
159	 * If the caller wishes to use it for a basic rate, they should
160	 * clear the high bit first.
161	 */
162	KASSERT(! (rate & 0x80), ("rate %d is basic/mcs?", rate));
163
164	return rt->rateCodeToIndex[rate] != (uint8_t)-1;
165}
166
167/*
168 * Calculate ACK field for
169 * o  non-fragment data frames
170 * o  management frames
171 * sent using rate, phy and short preamble setting.
172 */
173static __inline__ uint16_t
174ieee80211_ack_duration(const struct ieee80211_rate_table *rt,
175    uint8_t rate, int isShortPreamble)
176{
177	uint8_t rix = rt->rateCodeToIndex[rate];
178
179	KASSERT(rix != (uint8_t)-1, ("rate %d has no info", rate));
180	if (isShortPreamble) {
181		KASSERT(rt->info[rix].spAckDuration != 0,
182			("shpreamble ack dur is not computed!\n"));
183		return rt->info[rix].spAckDuration;
184	} else {
185		KASSERT(rt->info[rix].lpAckDuration != 0,
186			("lgpreamble ack dur is not computed!\n"));
187		return rt->info[rix].lpAckDuration;
188	}
189}
190
191static __inline__ uint8_t
192ieee80211_legacy_rate_lookup(const struct ieee80211_rate_table *rt,
193    uint8_t rate)
194{
195
196	return (rt->rateCodeToIndex[rate & IEEE80211_RATE_VAL]);
197}
198
199/*
200 * Compute the time to transmit a frame of length frameLen bytes
201 * using the specified 802.11 rate code, phy, and short preamble
202 * setting.
203 *
204 * NB: SIFS is included.
205 */
206uint16_t	ieee80211_compute_duration(const struct ieee80211_rate_table *,
207			uint32_t frameLen, uint16_t rate, int isShortPreamble);
208/*
209 * Convert PLCP signal/rate field to 802.11 rate code (.5Mbits/s)
210 */
211uint8_t		ieee80211_plcp2rate(uint8_t, enum ieee80211_phytype);
212/*
213 * Convert 802.11 rate code to PLCP signal.
214 */
215uint8_t		ieee80211_rate2plcp(int, enum ieee80211_phytype);
216
217/*
218 * 802.11n rate manipulation.
219 */
220
221#define	IEEE80211_HT_RC_2_MCS(_rc)	((_rc) & 0x1f)
222#define	IEEE80211_HT_RC_2_STREAMS(_rc)	((((_rc) & 0x78) >> 3) + 1)
223#define	IEEE80211_IS_HT_RATE(_rc)		( (_rc) & IEEE80211_RATE_MCS)
224
225uint32_t	ieee80211_compute_duration_ht(uint32_t frameLen,
226			uint16_t rate, int streams, int isht40,
227			int isShortGI);
228
229#endif	/* _KERNEL */
230#endif	/* !_NET80211_IEEE80211_PHY_H_ */
231