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 _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 #define IEEE80211_GET_SLOTTIME(ic) \ 57 ((ic->ic_flags & IEEE80211_F_SHSLOT) ? \ 58 IEEE80211_DUR_SHSLOT : IEEE80211_DUR_SLOT) 59 60 /* 61 * DIFS (microseconds). 62 */ 63 #define IEEE80211_DUR_DIFS(sifs, slot) ((sifs) + 2 * (slot)) 64 65 struct ieee80211_channel; 66 67 #define IEEE80211_RATE_TABLE_SIZE 128 68 69 struct ieee80211_rate_table { 70 int rateCount; /* NB: for proper padding */ 71 uint8_t rateCodeToIndex[256]; /* back mapping */ 72 struct { 73 uint8_t phy; /* CCK/OFDM/TURBO */ 74 uint32_t rateKbps; /* transfer rate in kbs */ 75 uint8_t shortPreamble; /* mask for enabling short 76 * preamble in CCK rate code */ 77 uint8_t dot11Rate; /* value for supported rates 78 * info element of MLME */ 79 uint8_t ctlRateIndex; /* index of next lower basic 80 * rate; used for dur. calcs */ 81 uint16_t lpAckDuration; /* long preamble ACK dur. */ 82 uint16_t spAckDuration; /* short preamble ACK dur. */ 83 } info[IEEE80211_RATE_TABLE_SIZE]; 84 }; 85 86 const struct ieee80211_rate_table *ieee80211_get_ratetable( 87 struct ieee80211_channel *); 88 89 static __inline__ uint8_t 90 ieee80211_ack_rate(const struct ieee80211_rate_table *rt, uint8_t rate) 91 { 92 /* 93 * XXX Assert this is for a legacy rate; not for an MCS rate. 94 * If the caller wishes to use it for a basic rate, they should 95 * clear the high bit first. 96 */ 97 KASSERT(! (rate & 0x80), ("rate %d is basic/mcs?", rate)); 98 99 uint8_t cix = rt->info[rt->rateCodeToIndex[rate & IEEE80211_RATE_VAL]].ctlRateIndex; 100 KASSERT(cix != (uint8_t)-1, ("rate %d has no info", rate)); 101 return rt->info[cix].dot11Rate; 102 } 103 104 static __inline__ uint8_t 105 ieee80211_ctl_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 } 118 119 static __inline__ enum ieee80211_phytype 120 ieee80211_rate2phytype(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 rix = rt->rateCodeToIndex[rate & IEEE80211_RATE_VAL]; 130 KASSERT(rix != (uint8_t)-1, ("rate %d has no info", rate)); 131 return rt->info[rix].phy; 132 } 133 134 static __inline__ int 135 ieee80211_isratevalid(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 return rt->rateCodeToIndex[rate] != (uint8_t)-1; 145 } 146 147 /* 148 * Calculate ACK field for 149 * o non-fragment data frames 150 * o management frames 151 * sent using rate, phy and short preamble setting. 152 */ 153 static __inline__ uint16_t 154 ieee80211_ack_duration(const struct ieee80211_rate_table *rt, 155 uint8_t rate, int isShortPreamble) 156 { 157 uint8_t rix = rt->rateCodeToIndex[rate]; 158 159 KASSERT(rix != (uint8_t)-1, ("rate %d has no info", rate)); 160 if (isShortPreamble) { 161 KASSERT(rt->info[rix].spAckDuration != 0, 162 ("shpreamble ack dur is not computed!\n")); 163 return rt->info[rix].spAckDuration; 164 } else { 165 KASSERT(rt->info[rix].lpAckDuration != 0, 166 ("lgpreamble ack dur is not computed!\n")); 167 return rt->info[rix].lpAckDuration; 168 } 169 } 170 171 static __inline__ uint8_t 172 ieee80211_legacy_rate_lookup(const struct ieee80211_rate_table *rt, 173 uint8_t rate) 174 { 175 176 return (rt->rateCodeToIndex[rate & IEEE80211_RATE_VAL]); 177 } 178 179 /* 180 * Compute the time to transmit a frame of length frameLen bytes 181 * using the specified 802.11 rate code, phy, and short preamble 182 * setting. 183 * 184 * NB: SIFS is included. 185 */ 186 uint16_t ieee80211_compute_duration(const struct ieee80211_rate_table *, 187 uint32_t frameLen, uint16_t rate, int isShortPreamble); 188 /* 189 * Convert PLCP signal/rate field to 802.11 rate code (.5Mbits/s) 190 */ 191 uint8_t ieee80211_plcp2rate(uint8_t, enum ieee80211_phytype); 192 /* 193 * Convert 802.11 rate code to PLCP signal. 194 */ 195 uint8_t ieee80211_rate2plcp(int, enum ieee80211_phytype); 196 197 uint32_t ieee80211_compute_duration_ht(uint32_t frameLen, 198 uint16_t rate, int streams, int isht40, 199 int isShortGI); 200 201 #endif /* _KERNEL */ 202 #endif /* !_NET80211_IEEE80211_PHY_H_ */ 203