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 /* 57 * DIFS (microseconds). 58 */ 59 #define IEEE80211_DUR_DIFS(sifs, slot) ((sifs) + 2 * (slot)) 60 61 struct ieee80211_channel; 62 63 #define IEEE80211_RATE_TABLE_SIZE 128 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[IEEE80211_RATE_TABLE_SIZE]; 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 /* 89 * XXX Assert this is for a legacy rate; not for an MCS rate. 90 * If the caller wishes to use it for a basic rate, they should 91 * clear the high bit first. 92 */ 93 KASSERT(! (rate & 0x80), ("rate %d is basic/mcs?", rate)); 94 95 uint8_t cix = rt->info[rt->rateCodeToIndex[rate & IEEE80211_RATE_VAL]].ctlRateIndex; 96 KASSERT(cix != (uint8_t)-1, ("rate %d has no info", rate)); 97 return rt->info[cix].dot11Rate; 98 } 99 100 static __inline__ uint8_t 101 ieee80211_ctl_rate(const struct ieee80211_rate_table *rt, uint8_t rate) 102 { 103 /* 104 * XXX Assert this is for a legacy rate; not for an MCS rate. 105 * If the caller wishes to use it for a basic rate, they should 106 * clear the high bit first. 107 */ 108 KASSERT(! (rate & 0x80), ("rate %d is basic/mcs?", rate)); 109 110 uint8_t cix = rt->info[rt->rateCodeToIndex[rate & IEEE80211_RATE_VAL]].ctlRateIndex; 111 KASSERT(cix != (uint8_t)-1, ("rate %d has no info", rate)); 112 return rt->info[cix].dot11Rate; 113 } 114 115 static __inline__ enum ieee80211_phytype 116 ieee80211_rate2phytype(const struct ieee80211_rate_table *rt, uint8_t rate) 117 { 118 /* 119 * XXX Assert this is for a legacy rate; not for an MCS rate. 120 * If the caller wishes to use it for a basic rate, they should 121 * clear the high bit first. 122 */ 123 KASSERT(! (rate & 0x80), ("rate %d is basic/mcs?", rate)); 124 125 uint8_t rix = rt->rateCodeToIndex[rate & IEEE80211_RATE_VAL]; 126 KASSERT(rix != (uint8_t)-1, ("rate %d has no info", rate)); 127 return rt->info[rix].phy; 128 } 129 130 static __inline__ int 131 ieee80211_isratevalid(const struct ieee80211_rate_table *rt, uint8_t rate) 132 { 133 /* 134 * XXX Assert this is for a legacy rate; not for an MCS rate. 135 * If the caller wishes to use it for a basic rate, they should 136 * clear the high bit first. 137 */ 138 KASSERT(! (rate & 0x80), ("rate %d is basic/mcs?", rate)); 139 140 return rt->rateCodeToIndex[rate] != (uint8_t)-1; 141 } 142 143 /* 144 * Calculate ACK field for 145 * o non-fragment data frames 146 * o management frames 147 * sent using rate, phy and short preamble setting. 148 */ 149 static __inline__ uint16_t 150 ieee80211_ack_duration(const struct ieee80211_rate_table *rt, 151 uint8_t rate, int isShortPreamble) 152 { 153 uint8_t rix = rt->rateCodeToIndex[rate]; 154 155 KASSERT(rix != (uint8_t)-1, ("rate %d has no info", rate)); 156 if (isShortPreamble) { 157 KASSERT(rt->info[rix].spAckDuration != 0, 158 ("shpreamble ack dur is not computed!\n")); 159 return rt->info[rix].spAckDuration; 160 } else { 161 KASSERT(rt->info[rix].lpAckDuration != 0, 162 ("lgpreamble ack dur is not computed!\n")); 163 return rt->info[rix].lpAckDuration; 164 } 165 } 166 167 static __inline__ uint8_t 168 ieee80211_legacy_rate_lookup(const struct ieee80211_rate_table *rt, 169 uint8_t rate) 170 { 171 172 return (rt->rateCodeToIndex[rate & IEEE80211_RATE_VAL]); 173 } 174 175 /* 176 * Compute the time to transmit a frame of length frameLen bytes 177 * using the specified 802.11 rate code, phy, and short preamble 178 * setting. 179 * 180 * NB: SIFS is included. 181 */ 182 uint16_t ieee80211_compute_duration(const struct ieee80211_rate_table *, 183 uint32_t frameLen, uint16_t rate, int isShortPreamble); 184 /* 185 * Convert PLCP signal/rate field to 802.11 rate code (.5Mbits/s) 186 */ 187 uint8_t ieee80211_plcp2rate(uint8_t, enum ieee80211_phytype); 188 /* 189 * Convert 802.11 rate code to PLCP signal. 190 */ 191 uint8_t ieee80211_rate2plcp(int, enum ieee80211_phytype); 192 193 uint32_t ieee80211_compute_duration_ht(uint32_t frameLen, 194 uint16_t rate, int streams, int isht40, 195 int isShortGI); 196 197 #endif /* _KERNEL */ 198 #endif /* !_NET80211_IEEE80211_PHY_H_ */ 199