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: head/sys/net80211/ieee80211_phy.h 193072 2009-05-29 23:39:16Z sam $ 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 struct ieee80211_rate_table { 64 int rateCount; /* NB: for proper padding */ 65 uint8_t rateCodeToIndex[256]; /* back mapping */ 66 struct { 67 uint8_t phy; /* CCK/OFDM/TURBO */ 68 uint32_t rateKbps; /* transfer rate in kbs */ 69 uint8_t shortPreamble; /* mask for enabling short 70 * preamble in CCK rate code */ 71 uint8_t dot11Rate; /* value for supported rates 72 * info element of MLME */ 73 uint8_t ctlRateIndex; /* index of next lower basic 74 * rate; used for dur. calcs */ 75 uint16_t lpAckDuration; /* long preamble ACK dur. */ 76 uint16_t spAckDuration; /* short preamble ACK dur. */ 77 } info[32]; 78 }; 79 80 const struct ieee80211_rate_table *ieee80211_get_ratetable( 81 struct ieee80211_channel *); 82 83 static __inline__ uint8_t 84 ieee80211_ack_rate(const struct ieee80211_rate_table *rt, uint8_t rate) 85 { 86 uint8_t cix = rt->info[rt->rateCodeToIndex[rate]].ctlRateIndex; 87 KASSERT(cix != (uint8_t)-1, ("rate %d has no info", rate)); 88 return rt->info[cix].dot11Rate; 89 } 90 91 static __inline__ uint8_t 92 ieee80211_ctl_rate(const struct ieee80211_rate_table *rt, uint8_t rate) 93 { 94 uint8_t cix = rt->info[rt->rateCodeToIndex[rate]].ctlRateIndex; 95 KASSERT(cix != (uint8_t)-1, ("rate %d has no info", rate)); 96 return rt->info[cix].dot11Rate; 97 } 98 99 static __inline__ enum ieee80211_phytype 100 ieee80211_rate2phytype(const struct ieee80211_rate_table *rt, uint8_t rate) 101 { 102 uint8_t rix = rt->rateCodeToIndex[rate]; 103 KASSERT(rix != (uint8_t)-1, ("rate %d has no info", rate)); 104 return rt->info[rix].phy; 105 } 106 107 static __inline__ int 108 ieee80211_isratevalid(const struct ieee80211_rate_table *rt, uint8_t rate) 109 { 110 return rt->rateCodeToIndex[rate] != (uint8_t)-1; 111 } 112 113 /* 114 * Calculate ACK field for 115 * o non-fragment data frames 116 * o management frames 117 * sent using rate, phy and short preamble setting. 118 */ 119 static __inline__ uint16_t 120 ieee80211_ack_duration(const struct ieee80211_rate_table *rt, 121 uint8_t rate, int isShortPreamble) 122 { 123 uint8_t rix = rt->rateCodeToIndex[rate]; 124 125 KASSERT(rix != (uint8_t)-1, ("rate %d has no info", rate)); 126 if (isShortPreamble) { 127 KASSERT(rt->info[rix].spAckDuration != 0, 128 ("shpreamble ack dur is not computed!")); 129 return rt->info[rix].spAckDuration; 130 } else { 131 KASSERT(rt->info[rix].lpAckDuration != 0, 132 ("lgpreamble ack dur is not computed!")); 133 return rt->info[rix].lpAckDuration; 134 } 135 } 136 137 /* 138 * Compute the time to transmit a frame of length frameLen bytes 139 * using the specified 802.11 rate code, phy, and short preamble 140 * setting. 141 * 142 * NB: SIFS is included. 143 */ 144 uint16_t ieee80211_compute_duration(const struct ieee80211_rate_table *, 145 uint32_t frameLen, uint16_t rate, int isShortPreamble); 146 /* 147 * Convert PLCP signal/rate field to 802.11 rate code (.5Mbits/s) 148 */ 149 uint8_t ieee80211_plcp2rate(uint8_t, enum ieee80211_phytype); 150 /* 151 * Convert 802.11 rate code to PLCP signal. 152 */ 153 uint8_t ieee80211_rate2plcp(int, enum ieee80211_phytype); 154 #endif /* _KERNEL */ 155 #endif /* !_NET80211_IEEE80211_PHY_H_ */ 156