1 /*- 2 * Copyright (c) 2005 John Bicket 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 * without modification. 11 * 2. Redistributions in binary form must reproduce at minimum a disclaimer 12 * similar to the "NO WARRANTY" disclaimer below ("Disclaimer") and any 13 * redistribution must be conditioned upon including a substantially 14 * similar Disclaimer requirement for further binary redistribution. 15 * 3. Neither the names of the above-listed copyright holders nor the names 16 * of any contributors may be used to endorse or promote products derived 17 * from this software without specific prior written permission. 18 * 19 * Alternatively, this software may be distributed under the terms of the 20 * GNU General Public License ("GPL") version 2 as published by the Free 21 * Software Foundation. 22 * 23 * NO WARRANTY 24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 25 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 26 * LIMITED TO, THE IMPLIED WARRANTIES OF NONINFRINGEMENT, MERCHANTIBILITY 27 * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 28 * THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, 29 * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER 32 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 34 * THE POSSIBILITY OF SUCH DAMAGES. 35 * 36 * $FreeBSD$ 37 */ 38 39 /* 40 * Defintions for the Atheros Wireless LAN controller driver. 41 */ 42 #ifndef _DEV_ATH_RATE_SAMPLE_H 43 #define _DEV_ATH_RATE_SAMPLE_H 44 45 /* per-device state */ 46 struct sample_softc { 47 struct ath_ratectrl arc; /* base class */ 48 int smoothing_rate; /* ewma percentage [0..99] */ 49 int smoothing_minpackets; 50 int sample_rate; /* %time to try different tx rates */ 51 int max_successive_failures; 52 int stale_failure_timeout; /* how long to honor max_successive_failures */ 53 int min_switch; /* min time between rate changes */ 54 }; 55 #define ATH_SOFTC_SAMPLE(sc) ((struct sample_softc *)sc->sc_rc) 56 57 struct rate_stats { 58 unsigned average_tx_time; 59 int successive_failures; 60 int tries; 61 int total_packets; 62 int packets_acked; 63 unsigned perfect_tx_time; /* transmit time for 0 retries */ 64 int last_tx; 65 }; 66 67 struct txschedule { 68 uint8_t t0, r0; /* series 0: tries, rate code */ 69 uint8_t t1, r1; /* series 1: tries, rate code */ 70 uint8_t t2, r2; /* series 2: tries, rate code */ 71 uint8_t t3, r3; /* series 3: tries, rate code */ 72 }; 73 74 /* 75 * for now, we track performance for three different packet 76 * size buckets 77 */ 78 #define NUM_PACKET_SIZE_BINS 2 79 80 /* per-node state */ 81 struct sample_node { 82 int static_rix; /* rate index of fixed tx rate */ 83 #define SAMPLE_MAXRATES 32 /* NB: corresponds to hal info[32] */ 84 uint32_t ratemask; /* bit mask of valid rate indices */ 85 const struct txschedule *sched; /* tx schedule table */ 86 87 struct rate_stats stats[NUM_PACKET_SIZE_BINS][SAMPLE_MAXRATES]; 88 int last_sample_rix[NUM_PACKET_SIZE_BINS]; 89 90 int current_sample_rix[NUM_PACKET_SIZE_BINS]; 91 int packets_sent[NUM_PACKET_SIZE_BINS]; 92 93 int current_rix[NUM_PACKET_SIZE_BINS]; 94 int packets_since_switch[NUM_PACKET_SIZE_BINS]; 95 unsigned ticks_since_switch[NUM_PACKET_SIZE_BINS]; 96 97 int packets_since_sample[NUM_PACKET_SIZE_BINS]; 98 unsigned sample_tt[NUM_PACKET_SIZE_BINS]; 99 }; 100 #define ATH_NODE_SAMPLE(an) ((struct sample_node *)&(an)[1]) 101 #define IS_RATE_DEFINED(sn, rix) (((sn)->ratemask & (1<<(rix))) != 0) 102 103 #ifndef MIN 104 #define MIN(a,b) ((a) < (b) ? (a) : (b)) 105 #endif 106 #ifndef MAX 107 #define MAX(a,b) ((a) > (b) ? (a) : (b)) 108 #endif 109 110 #define WIFI_CW_MIN 31 111 #define WIFI_CW_MAX 1023 112 113 /* 114 * Calculate the transmit duration of a frame. 115 */ 116 static unsigned calc_usecs_unicast_packet(struct ath_softc *sc, 117 int length, 118 int rix, int short_retries, 119 int long_retries, int is_ht40) 120 { 121 const HAL_RATE_TABLE *rt = sc->sc_currates; 122 struct ifnet *ifp = sc->sc_ifp; 123 struct ieee80211com *ic = ifp->if_l2com; 124 int rts, cts; 125 126 unsigned t_slot = 20; 127 unsigned t_difs = 50; 128 unsigned t_sifs = 10; 129 int tt = 0; 130 int x = 0; 131 int cw = WIFI_CW_MIN; 132 int cix; 133 134 KASSERT(rt != NULL, ("no rate table, mode %u", sc->sc_curmode)); 135 136 if (rix >= rt->rateCount) { 137 printf("bogus rix %d, max %u, mode %u\n", 138 rix, rt->rateCount, sc->sc_curmode); 139 return 0; 140 } 141 cix = rt->info[rix].controlRate; 142 /* 143 * XXX getting mac/phy level timings should be fixed for turbo 144 * rates, and there is probably a way to get this from the 145 * hal... 146 */ 147 switch (rt->info[rix].phy) { 148 case IEEE80211_T_OFDM: 149 t_slot = 9; 150 t_sifs = 16; 151 t_difs = 28; 152 /* fall through */ 153 case IEEE80211_T_TURBO: 154 t_slot = 9; 155 t_sifs = 8; 156 t_difs = 28; 157 break; 158 case IEEE80211_T_HT: 159 t_slot = 9; 160 t_sifs = 8; 161 t_difs = 28; 162 break; 163 case IEEE80211_T_DS: 164 /* fall through to default */ 165 default: 166 /* pg 205 ieee.802.11.pdf */ 167 t_slot = 20; 168 t_difs = 50; 169 t_sifs = 10; 170 } 171 172 rts = cts = 0; 173 174 if ((ic->ic_flags & IEEE80211_F_USEPROT) && 175 rt->info[rix].phy == IEEE80211_T_OFDM) { 176 if (ic->ic_protmode == IEEE80211_PROT_RTSCTS) 177 rts = 1; 178 else if (ic->ic_protmode == IEEE80211_PROT_CTSONLY) 179 cts = 1; 180 181 cix = rt->info[sc->sc_protrix].controlRate; 182 } 183 184 if (0 /*length > ic->ic_rtsthreshold */) { 185 rts = 1; 186 } 187 188 if (rts || cts) { 189 int ctsrate; 190 int ctsduration = 0; 191 192 /* NB: this is intentionally not a runtime check */ 193 KASSERT(cix < rt->rateCount, 194 ("bogus cix %d, max %u, mode %u\n", cix, rt->rateCount, 195 sc->sc_curmode)); 196 197 ctsrate = rt->info[cix].rateCode | rt->info[cix].shortPreamble; 198 if (rts) /* SIFS + CTS */ 199 ctsduration += rt->info[cix].spAckDuration; 200 201 /* XXX assumes short preamble */ 202 /* XXX assumes HT/20; the node info isn't yet available here */ 203 ctsduration += ath_hal_pkt_txtime(sc->sc_ah, rt, length, rix, 0, is_ht40); 204 205 if (cts) /* SIFS + ACK */ 206 ctsduration += rt->info[cix].spAckDuration; 207 208 tt += (short_retries + 1) * ctsduration; 209 } 210 tt += t_difs; 211 212 /* XXX assumes short preamble */ 213 /* XXX assumes HT/20; the node info isn't yet available here */ 214 tt += (long_retries+1)*ath_hal_pkt_txtime(sc->sc_ah, rt, length, rix, 0, is_ht40); 215 tt += (long_retries+1)*(t_sifs + rt->info[rix].spAckDuration); 216 217 for (x = 0; x <= short_retries + long_retries; x++) { 218 cw = MIN(WIFI_CW_MAX, (cw + 1) * 2); 219 tt += (t_slot * cw/2); 220 } 221 return tt; 222 } 223 #endif /* _DEV_ATH_RATE_SAMPLE_H */ 224