xref: /haiku/src/libs/compat/freebsd_wlan/net80211/ieee80211_phy.h (revision 83b1a68c52ba3e0e8796282759f694b7fdddf06d)
1 /*-
2  * Copyright (c) 2007-2008 Sam Leffler, Errno Consulting
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24  *
25  * $FreeBSD$
26  */
27 
28 #ifndef _FBSD_COMPAT_NET80211_IEEE80211_PHY_H_
29 #define _FBSD_COMPAT_NET80211_IEEE80211_PHY_H_
30 
31 #ifdef _KERNEL
32 /*
33  * IEEE 802.11 PHY-related definitions.
34  */
35 
36 void ieee80211_phy_init(void);
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  * DIFS (microseconds).
60  */
61 #define IEEE80211_DUR_DIFS(sifs, slot)	((sifs) + 2 * (slot))
62 
63 struct ieee80211_channel;
64 
65 struct ieee80211_rate_table {
66 	int		rateCount;		/* NB: for proper padding */
67 	uint8_t		rateCodeToIndex[256];	/* back mapping */
68 	struct {
69 		uint8_t		phy;		/* CCK/OFDM/TURBO */
70 		uint32_t	rateKbps;	/* transfer rate in kbs */
71 		uint8_t		shortPreamble;	/* mask for enabling short
72 						 * preamble in CCK rate code */
73 		uint8_t		dot11Rate;	/* value for supported rates
74 						 * info element of MLME */
75 		uint8_t		ctlRateIndex;	/* index of next lower basic
76 						 * rate; used for dur. calcs */
77 		uint16_t	lpAckDuration;	/* long preamble ACK dur. */
78 		uint16_t	spAckDuration;	/* short preamble ACK dur. */
79 	} info[32];
80 };
81 
82 const struct ieee80211_rate_table *ieee80211_get_ratetable(
83 			struct ieee80211_channel *);
84 
85 static __inline__ uint8_t
86 ieee80211_ack_rate(const struct ieee80211_rate_table *rt, uint8_t rate)
87 {
88 	uint8_t cix = rt->info[rt->rateCodeToIndex[rate]].ctlRateIndex;
89 	KASSERT(cix != (uint8_t)-1, ("rate %d has no info", rate));
90 	return rt->info[cix].dot11Rate;
91 }
92 
93 static __inline__ uint8_t
94 ieee80211_ctl_rate(const struct ieee80211_rate_table *rt, uint8_t rate)
95 {
96 	uint8_t cix = rt->info[rt->rateCodeToIndex[rate]].ctlRateIndex;
97 	KASSERT(cix != (uint8_t)-1, ("rate %d has no info", rate));
98 	return rt->info[cix].dot11Rate;
99 }
100 
101 static __inline__ enum ieee80211_phytype
102 ieee80211_rate2phytype(const struct ieee80211_rate_table *rt, uint8_t rate)
103 {
104 	uint8_t rix = rt->rateCodeToIndex[rate];
105 	KASSERT(rix != (uint8_t)-1, ("rate %d has no info", rate));
106 	return (enum ieee80211_phytype)rt->info[rix].phy;
107 }
108 
109 static __inline__ int
110 ieee80211_isratevalid(const struct ieee80211_rate_table *rt, uint8_t rate)
111 {
112 	return rt->rateCodeToIndex[rate] != (uint8_t)-1;
113 }
114 
115 /*
116  * Calculate ACK field for
117  * o  non-fragment data frames
118  * o  management frames
119  * sent using rate, phy and short preamble setting.
120  */
121 static __inline__ uint16_t
122 ieee80211_ack_duration(const struct ieee80211_rate_table *rt,
123     uint8_t rate, int isShortPreamble)
124 {
125 	uint8_t rix = rt->rateCodeToIndex[rate];
126 
127 	KASSERT(rix != (uint8_t)-1, ("rate %d has no info", rate));
128 	if (isShortPreamble) {
129 		KASSERT(rt->info[rix].spAckDuration != 0,
130 			("shpreamble ack dur is not computed!\n"));
131 		return rt->info[rix].spAckDuration;
132 	} else {
133 		KASSERT(rt->info[rix].lpAckDuration != 0,
134 			("lgpreamble ack dur is not computed!\n"));
135 		return rt->info[rix].lpAckDuration;
136 	}
137 }
138 
139 /*
140  * Compute the time to transmit a frame of length frameLen bytes
141  * using the specified 802.11 rate code, phy, and short preamble
142  * setting.
143  *
144  * NB: SIFS is included.
145  */
146 uint16_t	ieee80211_compute_duration(const struct ieee80211_rate_table *,
147 			uint32_t frameLen, uint16_t rate, int isShortPreamble);
148 /*
149  * Convert PLCP signal/rate field to 802.11 rate code (.5Mbits/s)
150  */
151 uint8_t		ieee80211_plcp2rate(uint8_t, enum ieee80211_phytype);
152 /*
153  * Convert 802.11 rate code to PLCP signal.
154  */
155 uint8_t		ieee80211_rate2plcp(int, enum ieee80211_phytype);
156 #endif	/* _KERNEL */
157 #endif	/* _FBSD_COMPAT_NET80211_IEEE80211_PHY_H_ */
158