1 /* 2 * Copyright (C) 2010-2013 Felix Fietkau <nbd@openwrt.org> 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 as 6 * published by the Free Software Foundation. 7 */ 8 #include <linux/netdevice.h> 9 #include <linux/types.h> 10 #include <linux/skbuff.h> 11 #include <linux/debugfs.h> 12 #include <linux/random.h> 13 #include <linux/moduleparam.h> 14 #include <linux/ieee80211.h> 15 #include <net/mac80211.h> 16 #include "rate.h" 17 #include "rc80211_minstrel.h" 18 #include "rc80211_minstrel_ht.h" 19 20 #define AVG_AMPDU_SIZE 16 21 #define AVG_PKT_SIZE 1200 22 23 /* Number of bits for an average sized packet */ 24 #define MCS_NBITS ((AVG_PKT_SIZE * AVG_AMPDU_SIZE) << 3) 25 26 /* Number of symbols for a packet with (bps) bits per symbol */ 27 #define MCS_NSYMS(bps) DIV_ROUND_UP(MCS_NBITS, (bps)) 28 29 /* Transmission time (nanoseconds) for a packet containing (syms) symbols */ 30 #define MCS_SYMBOL_TIME(sgi, syms) \ 31 (sgi ? \ 32 ((syms) * 18000 + 4000) / 5 : /* syms * 3.6 us */ \ 33 ((syms) * 1000) << 2 /* syms * 4 us */ \ 34 ) 35 36 /* Transmit duration for the raw data part of an average sized packet */ 37 #define MCS_DURATION(streams, sgi, bps) \ 38 (MCS_SYMBOL_TIME(sgi, MCS_NSYMS((streams) * (bps))) / AVG_AMPDU_SIZE) 39 40 #define BW_20 0 41 #define BW_40 1 42 #define BW_80 2 43 44 /* 45 * Define group sort order: HT40 -> SGI -> #streams 46 */ 47 #define GROUP_IDX(_streams, _sgi, _ht40) \ 48 MINSTREL_HT_GROUP_0 + \ 49 MINSTREL_MAX_STREAMS * 2 * _ht40 + \ 50 MINSTREL_MAX_STREAMS * _sgi + \ 51 _streams - 1 52 53 /* MCS rate information for an MCS group */ 54 #define MCS_GROUP(_streams, _sgi, _ht40) \ 55 [GROUP_IDX(_streams, _sgi, _ht40)] = { \ 56 .streams = _streams, \ 57 .flags = \ 58 IEEE80211_TX_RC_MCS | \ 59 (_sgi ? IEEE80211_TX_RC_SHORT_GI : 0) | \ 60 (_ht40 ? IEEE80211_TX_RC_40_MHZ_WIDTH : 0), \ 61 .duration = { \ 62 MCS_DURATION(_streams, _sgi, _ht40 ? 54 : 26), \ 63 MCS_DURATION(_streams, _sgi, _ht40 ? 108 : 52), \ 64 MCS_DURATION(_streams, _sgi, _ht40 ? 162 : 78), \ 65 MCS_DURATION(_streams, _sgi, _ht40 ? 216 : 104), \ 66 MCS_DURATION(_streams, _sgi, _ht40 ? 324 : 156), \ 67 MCS_DURATION(_streams, _sgi, _ht40 ? 432 : 208), \ 68 MCS_DURATION(_streams, _sgi, _ht40 ? 486 : 234), \ 69 MCS_DURATION(_streams, _sgi, _ht40 ? 540 : 260) \ 70 } \ 71 } 72 73 #define VHT_GROUP_IDX(_streams, _sgi, _bw) \ 74 (MINSTREL_VHT_GROUP_0 + \ 75 MINSTREL_MAX_STREAMS * 2 * (_bw) + \ 76 MINSTREL_MAX_STREAMS * (_sgi) + \ 77 (_streams) - 1) 78 79 #define BW2VBPS(_bw, r3, r2, r1) \ 80 (_bw == BW_80 ? r3 : _bw == BW_40 ? r2 : r1) 81 82 #define VHT_GROUP(_streams, _sgi, _bw) \ 83 [VHT_GROUP_IDX(_streams, _sgi, _bw)] = { \ 84 .streams = _streams, \ 85 .flags = \ 86 IEEE80211_TX_RC_VHT_MCS | \ 87 (_sgi ? IEEE80211_TX_RC_SHORT_GI : 0) | \ 88 (_bw == BW_80 ? IEEE80211_TX_RC_80_MHZ_WIDTH : \ 89 _bw == BW_40 ? IEEE80211_TX_RC_40_MHZ_WIDTH : 0), \ 90 .duration = { \ 91 MCS_DURATION(_streams, _sgi, \ 92 BW2VBPS(_bw, 117, 54, 26)), \ 93 MCS_DURATION(_streams, _sgi, \ 94 BW2VBPS(_bw, 234, 108, 52)), \ 95 MCS_DURATION(_streams, _sgi, \ 96 BW2VBPS(_bw, 351, 162, 78)), \ 97 MCS_DURATION(_streams, _sgi, \ 98 BW2VBPS(_bw, 468, 216, 104)), \ 99 MCS_DURATION(_streams, _sgi, \ 100 BW2VBPS(_bw, 702, 324, 156)), \ 101 MCS_DURATION(_streams, _sgi, \ 102 BW2VBPS(_bw, 936, 432, 208)), \ 103 MCS_DURATION(_streams, _sgi, \ 104 BW2VBPS(_bw, 1053, 486, 234)), \ 105 MCS_DURATION(_streams, _sgi, \ 106 BW2VBPS(_bw, 1170, 540, 260)), \ 107 MCS_DURATION(_streams, _sgi, \ 108 BW2VBPS(_bw, 1404, 648, 312)), \ 109 MCS_DURATION(_streams, _sgi, \ 110 BW2VBPS(_bw, 1560, 720, 346)) \ 111 } \ 112 } 113 114 #define CCK_DURATION(_bitrate, _short, _len) \ 115 (1000 * (10 /* SIFS */ + \ 116 (_short ? 72 + 24 : 144 + 48) + \ 117 (8 * (_len + 4) * 10) / (_bitrate))) 118 119 #define CCK_ACK_DURATION(_bitrate, _short) \ 120 (CCK_DURATION((_bitrate > 10 ? 20 : 10), false, 60) + \ 121 CCK_DURATION(_bitrate, _short, AVG_PKT_SIZE)) 122 123 #define CCK_DURATION_LIST(_short) \ 124 CCK_ACK_DURATION(10, _short), \ 125 CCK_ACK_DURATION(20, _short), \ 126 CCK_ACK_DURATION(55, _short), \ 127 CCK_ACK_DURATION(110, _short) 128 129 #define CCK_GROUP \ 130 [MINSTREL_CCK_GROUP] = { \ 131 .streams = 0, \ 132 .flags = 0, \ 133 .duration = { \ 134 CCK_DURATION_LIST(false), \ 135 CCK_DURATION_LIST(true) \ 136 } \ 137 } 138 139 #ifdef CONFIG_MAC80211_RC_MINSTREL_VHT 140 static bool minstrel_vht_only = true; 141 module_param(minstrel_vht_only, bool, 0644); 142 MODULE_PARM_DESC(minstrel_vht_only, 143 "Use only VHT rates when VHT is supported by sta."); 144 #endif 145 146 /* 147 * To enable sufficiently targeted rate sampling, MCS rates are divided into 148 * groups, based on the number of streams and flags (HT40, SGI) that they 149 * use. 150 * 151 * Sortorder has to be fixed for GROUP_IDX macro to be applicable: 152 * BW -> SGI -> #streams 153 */ 154 const struct mcs_group minstrel_mcs_groups[] = { 155 MCS_GROUP(1, 0, BW_20), 156 MCS_GROUP(2, 0, BW_20), 157 #if MINSTREL_MAX_STREAMS >= 3 158 MCS_GROUP(3, 0, BW_20), 159 #endif 160 161 MCS_GROUP(1, 1, BW_20), 162 MCS_GROUP(2, 1, BW_20), 163 #if MINSTREL_MAX_STREAMS >= 3 164 MCS_GROUP(3, 1, BW_20), 165 #endif 166 167 MCS_GROUP(1, 0, BW_40), 168 MCS_GROUP(2, 0, BW_40), 169 #if MINSTREL_MAX_STREAMS >= 3 170 MCS_GROUP(3, 0, BW_40), 171 #endif 172 173 MCS_GROUP(1, 1, BW_40), 174 MCS_GROUP(2, 1, BW_40), 175 #if MINSTREL_MAX_STREAMS >= 3 176 MCS_GROUP(3, 1, BW_40), 177 #endif 178 179 CCK_GROUP, 180 181 #ifdef CONFIG_MAC80211_RC_MINSTREL_VHT 182 VHT_GROUP(1, 0, BW_20), 183 VHT_GROUP(2, 0, BW_20), 184 #if MINSTREL_MAX_STREAMS >= 3 185 VHT_GROUP(3, 0, BW_20), 186 #endif 187 188 VHT_GROUP(1, 1, BW_20), 189 VHT_GROUP(2, 1, BW_20), 190 #if MINSTREL_MAX_STREAMS >= 3 191 VHT_GROUP(3, 1, BW_20), 192 #endif 193 194 VHT_GROUP(1, 0, BW_40), 195 VHT_GROUP(2, 0, BW_40), 196 #if MINSTREL_MAX_STREAMS >= 3 197 VHT_GROUP(3, 0, BW_40), 198 #endif 199 200 VHT_GROUP(1, 1, BW_40), 201 VHT_GROUP(2, 1, BW_40), 202 #if MINSTREL_MAX_STREAMS >= 3 203 VHT_GROUP(3, 1, BW_40), 204 #endif 205 206 VHT_GROUP(1, 0, BW_80), 207 VHT_GROUP(2, 0, BW_80), 208 #if MINSTREL_MAX_STREAMS >= 3 209 VHT_GROUP(3, 0, BW_80), 210 #endif 211 212 VHT_GROUP(1, 1, BW_80), 213 VHT_GROUP(2, 1, BW_80), 214 #if MINSTREL_MAX_STREAMS >= 3 215 VHT_GROUP(3, 1, BW_80), 216 #endif 217 #endif 218 }; 219 220 static u8 sample_table[SAMPLE_COLUMNS][MCS_GROUP_RATES] __read_mostly; 221 222 static void 223 minstrel_ht_update_rates(struct minstrel_priv *mp, struct minstrel_ht_sta *mi); 224 225 /* 226 * Some VHT MCSes are invalid (when Ndbps / Nes is not an integer) 227 * e.g for MCS9@20MHzx1Nss: Ndbps=8x52*(5/6) Nes=1 228 * 229 * Returns the valid mcs map for struct minstrel_mcs_group_data.supported 230 */ 231 static u16 232 minstrel_get_valid_vht_rates(int bw, int nss, __le16 mcs_map) 233 { 234 u16 mask = 0; 235 236 if (bw == BW_20) { 237 if (nss != 3 && nss != 6) 238 mask = BIT(9); 239 } else if (bw == BW_80) { 240 if (nss == 3 || nss == 7) 241 mask = BIT(6); 242 else if (nss == 6) 243 mask = BIT(9); 244 } else { 245 WARN_ON(bw != BW_40); 246 } 247 248 switch ((le16_to_cpu(mcs_map) >> (2 * (nss - 1))) & 3) { 249 case IEEE80211_VHT_MCS_SUPPORT_0_7: 250 mask |= 0x300; 251 break; 252 case IEEE80211_VHT_MCS_SUPPORT_0_8: 253 mask |= 0x200; 254 break; 255 case IEEE80211_VHT_MCS_SUPPORT_0_9: 256 break; 257 default: 258 mask = 0x3ff; 259 } 260 261 return 0x3ff & ~mask; 262 } 263 264 /* 265 * Look up an MCS group index based on mac80211 rate information 266 */ 267 static int 268 minstrel_ht_get_group_idx(struct ieee80211_tx_rate *rate) 269 { 270 return GROUP_IDX((rate->idx / 8) + 1, 271 !!(rate->flags & IEEE80211_TX_RC_SHORT_GI), 272 !!(rate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH)); 273 } 274 275 static int 276 minstrel_vht_get_group_idx(struct ieee80211_tx_rate *rate) 277 { 278 return VHT_GROUP_IDX(ieee80211_rate_get_vht_nss(rate), 279 !!(rate->flags & IEEE80211_TX_RC_SHORT_GI), 280 !!(rate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH) + 281 2*!!(rate->flags & IEEE80211_TX_RC_80_MHZ_WIDTH)); 282 } 283 284 static struct minstrel_rate_stats * 285 minstrel_ht_get_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi, 286 struct ieee80211_tx_rate *rate) 287 { 288 int group, idx; 289 290 if (rate->flags & IEEE80211_TX_RC_MCS) { 291 group = minstrel_ht_get_group_idx(rate); 292 idx = rate->idx % 8; 293 } else if (rate->flags & IEEE80211_TX_RC_VHT_MCS) { 294 group = minstrel_vht_get_group_idx(rate); 295 idx = ieee80211_rate_get_vht_mcs(rate); 296 } else { 297 group = MINSTREL_CCK_GROUP; 298 299 for (idx = 0; idx < ARRAY_SIZE(mp->cck_rates); idx++) 300 if (rate->idx == mp->cck_rates[idx]) 301 break; 302 303 /* short preamble */ 304 if (!(mi->groups[group].supported & BIT(idx))) 305 idx += 4; 306 } 307 return &mi->groups[group].rates[idx]; 308 } 309 310 static inline struct minstrel_rate_stats * 311 minstrel_get_ratestats(struct minstrel_ht_sta *mi, int index) 312 { 313 return &mi->groups[index / MCS_GROUP_RATES].rates[index % MCS_GROUP_RATES]; 314 } 315 316 /* 317 * Return current throughput based on the average A-MPDU length, taking into 318 * account the expected number of retransmissions and their expected length 319 */ 320 int 321 minstrel_ht_get_tp_avg(struct minstrel_ht_sta *mi, int group, int rate, 322 int prob_ewma) 323 { 324 unsigned int nsecs = 0; 325 326 /* do not account throughput if sucess prob is below 10% */ 327 if (prob_ewma < MINSTREL_FRAC(10, 100)) 328 return 0; 329 330 if (group != MINSTREL_CCK_GROUP) 331 nsecs = 1000 * mi->overhead / MINSTREL_TRUNC(mi->avg_ampdu_len); 332 333 nsecs += minstrel_mcs_groups[group].duration[rate]; 334 335 /* 336 * For the throughput calculation, limit the probability value to 90% to 337 * account for collision related packet error rate fluctuation 338 * (prob is scaled - see MINSTREL_FRAC above) 339 */ 340 if (prob_ewma > MINSTREL_FRAC(90, 100)) 341 return MINSTREL_TRUNC(100000 * ((MINSTREL_FRAC(90, 100) * 1000) 342 / nsecs)); 343 else 344 return MINSTREL_TRUNC(100000 * ((prob_ewma * 1000) / nsecs)); 345 } 346 347 /* 348 * Find & sort topmost throughput rates 349 * 350 * If multiple rates provide equal throughput the sorting is based on their 351 * current success probability. Higher success probability is preferred among 352 * MCS groups, CCK rates do not provide aggregation and are therefore at last. 353 */ 354 static void 355 minstrel_ht_sort_best_tp_rates(struct minstrel_ht_sta *mi, u16 index, 356 u16 *tp_list) 357 { 358 int cur_group, cur_idx, cur_tp_avg, cur_prob; 359 int tmp_group, tmp_idx, tmp_tp_avg, tmp_prob; 360 int j = MAX_THR_RATES; 361 362 cur_group = index / MCS_GROUP_RATES; 363 cur_idx = index % MCS_GROUP_RATES; 364 cur_prob = mi->groups[cur_group].rates[cur_idx].prob_ewma; 365 cur_tp_avg = minstrel_ht_get_tp_avg(mi, cur_group, cur_idx, cur_prob); 366 367 do { 368 tmp_group = tp_list[j - 1] / MCS_GROUP_RATES; 369 tmp_idx = tp_list[j - 1] % MCS_GROUP_RATES; 370 tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_ewma; 371 tmp_tp_avg = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx, 372 tmp_prob); 373 if (cur_tp_avg < tmp_tp_avg || 374 (cur_tp_avg == tmp_tp_avg && cur_prob <= tmp_prob)) 375 break; 376 j--; 377 } while (j > 0); 378 379 if (j < MAX_THR_RATES - 1) { 380 memmove(&tp_list[j + 1], &tp_list[j], (sizeof(*tp_list) * 381 (MAX_THR_RATES - (j + 1)))); 382 } 383 if (j < MAX_THR_RATES) 384 tp_list[j] = index; 385 } 386 387 /* 388 * Find and set the topmost probability rate per sta and per group 389 */ 390 static void 391 minstrel_ht_set_best_prob_rate(struct minstrel_ht_sta *mi, u16 index) 392 { 393 struct minstrel_mcs_group_data *mg; 394 struct minstrel_rate_stats *mrs; 395 int tmp_group, tmp_idx, tmp_tp_avg, tmp_prob; 396 int max_tp_group, cur_tp_avg, cur_group, cur_idx; 397 int max_gpr_group, max_gpr_idx; 398 int max_gpr_tp_avg, max_gpr_prob; 399 400 cur_group = index / MCS_GROUP_RATES; 401 cur_idx = index % MCS_GROUP_RATES; 402 mg = &mi->groups[index / MCS_GROUP_RATES]; 403 mrs = &mg->rates[index % MCS_GROUP_RATES]; 404 405 tmp_group = mi->max_prob_rate / MCS_GROUP_RATES; 406 tmp_idx = mi->max_prob_rate % MCS_GROUP_RATES; 407 tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_ewma; 408 tmp_tp_avg = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx, tmp_prob); 409 410 /* if max_tp_rate[0] is from MCS_GROUP max_prob_rate get selected from 411 * MCS_GROUP as well as CCK_GROUP rates do not allow aggregation */ 412 max_tp_group = mi->max_tp_rate[0] / MCS_GROUP_RATES; 413 if((index / MCS_GROUP_RATES == MINSTREL_CCK_GROUP) && 414 (max_tp_group != MINSTREL_CCK_GROUP)) 415 return; 416 417 if (mrs->prob_ewma > MINSTREL_FRAC(75, 100)) { 418 cur_tp_avg = minstrel_ht_get_tp_avg(mi, cur_group, cur_idx, 419 mrs->prob_ewma); 420 if (cur_tp_avg > tmp_tp_avg) 421 mi->max_prob_rate = index; 422 423 max_gpr_group = mg->max_group_prob_rate / MCS_GROUP_RATES; 424 max_gpr_idx = mg->max_group_prob_rate % MCS_GROUP_RATES; 425 max_gpr_prob = mi->groups[max_gpr_group].rates[max_gpr_idx].prob_ewma; 426 max_gpr_tp_avg = minstrel_ht_get_tp_avg(mi, max_gpr_group, 427 max_gpr_idx, 428 max_gpr_prob); 429 if (cur_tp_avg > max_gpr_tp_avg) 430 mg->max_group_prob_rate = index; 431 } else { 432 if (mrs->prob_ewma > tmp_prob) 433 mi->max_prob_rate = index; 434 if (mrs->prob_ewma > mg->rates[mg->max_group_prob_rate].prob_ewma) 435 mg->max_group_prob_rate = index; 436 } 437 } 438 439 440 /* 441 * Assign new rate set per sta and use CCK rates only if the fastest 442 * rate (max_tp_rate[0]) is from CCK group. This prohibits such sorted 443 * rate sets where MCS and CCK rates are mixed, because CCK rates can 444 * not use aggregation. 445 */ 446 static void 447 minstrel_ht_assign_best_tp_rates(struct minstrel_ht_sta *mi, 448 u16 tmp_mcs_tp_rate[MAX_THR_RATES], 449 u16 tmp_cck_tp_rate[MAX_THR_RATES]) 450 { 451 unsigned int tmp_group, tmp_idx, tmp_cck_tp, tmp_mcs_tp, tmp_prob; 452 int i; 453 454 tmp_group = tmp_cck_tp_rate[0] / MCS_GROUP_RATES; 455 tmp_idx = tmp_cck_tp_rate[0] % MCS_GROUP_RATES; 456 tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_ewma; 457 tmp_cck_tp = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx, tmp_prob); 458 459 tmp_group = tmp_mcs_tp_rate[0] / MCS_GROUP_RATES; 460 tmp_idx = tmp_mcs_tp_rate[0] % MCS_GROUP_RATES; 461 tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_ewma; 462 tmp_mcs_tp = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx, tmp_prob); 463 464 if (tmp_cck_tp > tmp_mcs_tp) { 465 for(i = 0; i < MAX_THR_RATES; i++) { 466 minstrel_ht_sort_best_tp_rates(mi, tmp_cck_tp_rate[i], 467 tmp_mcs_tp_rate); 468 } 469 } 470 471 } 472 473 /* 474 * Try to increase robustness of max_prob rate by decrease number of 475 * streams if possible. 476 */ 477 static inline void 478 minstrel_ht_prob_rate_reduce_streams(struct minstrel_ht_sta *mi) 479 { 480 struct minstrel_mcs_group_data *mg; 481 int tmp_max_streams, group, tmp_idx, tmp_prob; 482 int tmp_tp = 0; 483 484 tmp_max_streams = minstrel_mcs_groups[mi->max_tp_rate[0] / 485 MCS_GROUP_RATES].streams; 486 for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) { 487 mg = &mi->groups[group]; 488 if (!mg->supported || group == MINSTREL_CCK_GROUP) 489 continue; 490 491 tmp_idx = mg->max_group_prob_rate % MCS_GROUP_RATES; 492 tmp_prob = mi->groups[group].rates[tmp_idx].prob_ewma; 493 494 if (tmp_tp < minstrel_ht_get_tp_avg(mi, group, tmp_idx, tmp_prob) && 495 (minstrel_mcs_groups[group].streams < tmp_max_streams)) { 496 mi->max_prob_rate = mg->max_group_prob_rate; 497 tmp_tp = minstrel_ht_get_tp_avg(mi, group, 498 tmp_idx, 499 tmp_prob); 500 } 501 } 502 } 503 504 /* 505 * Update rate statistics and select new primary rates 506 * 507 * Rules for rate selection: 508 * - max_prob_rate must use only one stream, as a tradeoff between delivery 509 * probability and throughput during strong fluctuations 510 * - as long as the max prob rate has a probability of more than 75%, pick 511 * higher throughput rates, even if the probablity is a bit lower 512 */ 513 static void 514 minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi) 515 { 516 struct minstrel_mcs_group_data *mg; 517 struct minstrel_rate_stats *mrs; 518 int group, i, j, cur_prob; 519 u16 tmp_mcs_tp_rate[MAX_THR_RATES], tmp_group_tp_rate[MAX_THR_RATES]; 520 u16 tmp_cck_tp_rate[MAX_THR_RATES], index; 521 522 if (mi->ampdu_packets > 0) { 523 mi->avg_ampdu_len = minstrel_ewma(mi->avg_ampdu_len, 524 MINSTREL_FRAC(mi->ampdu_len, mi->ampdu_packets), EWMA_LEVEL); 525 mi->ampdu_len = 0; 526 mi->ampdu_packets = 0; 527 } 528 529 mi->sample_slow = 0; 530 mi->sample_count = 0; 531 532 /* Initialize global rate indexes */ 533 for(j = 0; j < MAX_THR_RATES; j++){ 534 tmp_mcs_tp_rate[j] = 0; 535 tmp_cck_tp_rate[j] = 0; 536 } 537 538 /* Find best rate sets within all MCS groups*/ 539 for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) { 540 541 mg = &mi->groups[group]; 542 if (!mg->supported) 543 continue; 544 545 mi->sample_count++; 546 547 /* (re)Initialize group rate indexes */ 548 for(j = 0; j < MAX_THR_RATES; j++) 549 tmp_group_tp_rate[j] = group; 550 551 for (i = 0; i < MCS_GROUP_RATES; i++) { 552 if (!(mg->supported & BIT(i))) 553 continue; 554 555 index = MCS_GROUP_RATES * group + i; 556 557 mrs = &mg->rates[i]; 558 mrs->retry_updated = false; 559 minstrel_calc_rate_stats(mrs); 560 cur_prob = mrs->prob_ewma; 561 562 if (minstrel_ht_get_tp_avg(mi, group, i, cur_prob) == 0) 563 continue; 564 565 /* Find max throughput rate set */ 566 if (group != MINSTREL_CCK_GROUP) { 567 minstrel_ht_sort_best_tp_rates(mi, index, 568 tmp_mcs_tp_rate); 569 } else if (group == MINSTREL_CCK_GROUP) { 570 minstrel_ht_sort_best_tp_rates(mi, index, 571 tmp_cck_tp_rate); 572 } 573 574 /* Find max throughput rate set within a group */ 575 minstrel_ht_sort_best_tp_rates(mi, index, 576 tmp_group_tp_rate); 577 578 /* Find max probability rate per group and global */ 579 minstrel_ht_set_best_prob_rate(mi, index); 580 } 581 582 memcpy(mg->max_group_tp_rate, tmp_group_tp_rate, 583 sizeof(mg->max_group_tp_rate)); 584 } 585 586 /* Assign new rate set per sta */ 587 minstrel_ht_assign_best_tp_rates(mi, tmp_mcs_tp_rate, tmp_cck_tp_rate); 588 memcpy(mi->max_tp_rate, tmp_mcs_tp_rate, sizeof(mi->max_tp_rate)); 589 590 /* Try to increase robustness of max_prob_rate*/ 591 minstrel_ht_prob_rate_reduce_streams(mi); 592 593 /* try to sample all available rates during each interval */ 594 mi->sample_count *= 8; 595 596 #ifdef CONFIG_MAC80211_DEBUGFS 597 /* use fixed index if set */ 598 if (mp->fixed_rate_idx != -1) { 599 for (i = 0; i < 4; i++) 600 mi->max_tp_rate[i] = mp->fixed_rate_idx; 601 mi->max_prob_rate = mp->fixed_rate_idx; 602 } 603 #endif 604 605 /* Reset update timer */ 606 mi->last_stats_update = jiffies; 607 } 608 609 static bool 610 minstrel_ht_txstat_valid(struct minstrel_priv *mp, struct ieee80211_tx_rate *rate) 611 { 612 if (rate->idx < 0) 613 return false; 614 615 if (!rate->count) 616 return false; 617 618 if (rate->flags & IEEE80211_TX_RC_MCS || 619 rate->flags & IEEE80211_TX_RC_VHT_MCS) 620 return true; 621 622 return rate->idx == mp->cck_rates[0] || 623 rate->idx == mp->cck_rates[1] || 624 rate->idx == mp->cck_rates[2] || 625 rate->idx == mp->cck_rates[3]; 626 } 627 628 static void 629 minstrel_set_next_sample_idx(struct minstrel_ht_sta *mi) 630 { 631 struct minstrel_mcs_group_data *mg; 632 633 for (;;) { 634 mi->sample_group++; 635 mi->sample_group %= ARRAY_SIZE(minstrel_mcs_groups); 636 mg = &mi->groups[mi->sample_group]; 637 638 if (!mg->supported) 639 continue; 640 641 if (++mg->index >= MCS_GROUP_RATES) { 642 mg->index = 0; 643 if (++mg->column >= ARRAY_SIZE(sample_table)) 644 mg->column = 0; 645 } 646 break; 647 } 648 } 649 650 static void 651 minstrel_downgrade_rate(struct minstrel_ht_sta *mi, u16 *idx, bool primary) 652 { 653 int group, orig_group; 654 655 orig_group = group = *idx / MCS_GROUP_RATES; 656 while (group > 0) { 657 group--; 658 659 if (!mi->groups[group].supported) 660 continue; 661 662 if (minstrel_mcs_groups[group].streams > 663 minstrel_mcs_groups[orig_group].streams) 664 continue; 665 666 if (primary) 667 *idx = mi->groups[group].max_group_tp_rate[0]; 668 else 669 *idx = mi->groups[group].max_group_tp_rate[1]; 670 break; 671 } 672 } 673 674 static void 675 minstrel_aggr_check(struct ieee80211_sta *pubsta, struct sk_buff *skb) 676 { 677 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 678 struct sta_info *sta = container_of(pubsta, struct sta_info, sta); 679 u16 tid; 680 681 if (skb_get_queue_mapping(skb) == IEEE80211_AC_VO) 682 return; 683 684 if (unlikely(!ieee80211_is_data_qos(hdr->frame_control))) 685 return; 686 687 if (unlikely(skb->protocol == cpu_to_be16(ETH_P_PAE))) 688 return; 689 690 tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK; 691 if (likely(sta->ampdu_mlme.tid_tx[tid])) 692 return; 693 694 ieee80211_start_tx_ba_session(pubsta, tid, 5000); 695 } 696 697 static void 698 minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband, 699 struct ieee80211_sta *sta, void *priv_sta, 700 struct ieee80211_tx_info *info) 701 { 702 struct minstrel_ht_sta_priv *msp = priv_sta; 703 struct minstrel_ht_sta *mi = &msp->ht; 704 struct ieee80211_tx_rate *ar = info->status.rates; 705 struct minstrel_rate_stats *rate, *rate2; 706 struct minstrel_priv *mp = priv; 707 bool last, update = false; 708 int i; 709 710 if (!msp->is_ht) 711 return mac80211_minstrel.tx_status_noskb(priv, sband, sta, 712 &msp->legacy, info); 713 714 /* This packet was aggregated but doesn't carry status info */ 715 if ((info->flags & IEEE80211_TX_CTL_AMPDU) && 716 !(info->flags & IEEE80211_TX_STAT_AMPDU)) 717 return; 718 719 if (!(info->flags & IEEE80211_TX_STAT_AMPDU)) { 720 info->status.ampdu_ack_len = 721 (info->flags & IEEE80211_TX_STAT_ACK ? 1 : 0); 722 info->status.ampdu_len = 1; 723 } 724 725 mi->ampdu_packets++; 726 mi->ampdu_len += info->status.ampdu_len; 727 728 if (!mi->sample_wait && !mi->sample_tries && mi->sample_count > 0) { 729 mi->sample_wait = 16 + 2 * MINSTREL_TRUNC(mi->avg_ampdu_len); 730 mi->sample_tries = 1; 731 mi->sample_count--; 732 } 733 734 if (info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE) 735 mi->sample_packets += info->status.ampdu_len; 736 737 last = !minstrel_ht_txstat_valid(mp, &ar[0]); 738 for (i = 0; !last; i++) { 739 last = (i == IEEE80211_TX_MAX_RATES - 1) || 740 !minstrel_ht_txstat_valid(mp, &ar[i + 1]); 741 742 rate = minstrel_ht_get_stats(mp, mi, &ar[i]); 743 744 if (last) 745 rate->success += info->status.ampdu_ack_len; 746 747 rate->attempts += ar[i].count * info->status.ampdu_len; 748 } 749 750 /* 751 * check for sudden death of spatial multiplexing, 752 * downgrade to a lower number of streams if necessary. 753 */ 754 rate = minstrel_get_ratestats(mi, mi->max_tp_rate[0]); 755 if (rate->attempts > 30 && 756 MINSTREL_FRAC(rate->success, rate->attempts) < 757 MINSTREL_FRAC(20, 100)) { 758 minstrel_downgrade_rate(mi, &mi->max_tp_rate[0], true); 759 update = true; 760 } 761 762 rate2 = minstrel_get_ratestats(mi, mi->max_tp_rate[1]); 763 if (rate2->attempts > 30 && 764 MINSTREL_FRAC(rate2->success, rate2->attempts) < 765 MINSTREL_FRAC(20, 100)) { 766 minstrel_downgrade_rate(mi, &mi->max_tp_rate[1], false); 767 update = true; 768 } 769 770 if (time_after(jiffies, mi->last_stats_update + 771 (mp->update_interval / 2 * HZ) / 1000)) { 772 update = true; 773 minstrel_ht_update_stats(mp, mi); 774 } 775 776 if (update) 777 minstrel_ht_update_rates(mp, mi); 778 } 779 780 static void 781 minstrel_calc_retransmit(struct minstrel_priv *mp, struct minstrel_ht_sta *mi, 782 int index) 783 { 784 struct minstrel_rate_stats *mrs; 785 const struct mcs_group *group; 786 unsigned int tx_time, tx_time_rtscts, tx_time_data; 787 unsigned int cw = mp->cw_min; 788 unsigned int ctime = 0; 789 unsigned int t_slot = 9; /* FIXME */ 790 unsigned int ampdu_len = MINSTREL_TRUNC(mi->avg_ampdu_len); 791 unsigned int overhead = 0, overhead_rtscts = 0; 792 793 mrs = minstrel_get_ratestats(mi, index); 794 if (mrs->prob_ewma < MINSTREL_FRAC(1, 10)) { 795 mrs->retry_count = 1; 796 mrs->retry_count_rtscts = 1; 797 return; 798 } 799 800 mrs->retry_count = 2; 801 mrs->retry_count_rtscts = 2; 802 mrs->retry_updated = true; 803 804 group = &minstrel_mcs_groups[index / MCS_GROUP_RATES]; 805 tx_time_data = group->duration[index % MCS_GROUP_RATES] * ampdu_len / 1000; 806 807 /* Contention time for first 2 tries */ 808 ctime = (t_slot * cw) >> 1; 809 cw = min((cw << 1) | 1, mp->cw_max); 810 ctime += (t_slot * cw) >> 1; 811 cw = min((cw << 1) | 1, mp->cw_max); 812 813 if (index / MCS_GROUP_RATES != MINSTREL_CCK_GROUP) { 814 overhead = mi->overhead; 815 overhead_rtscts = mi->overhead_rtscts; 816 } 817 818 /* Total TX time for data and Contention after first 2 tries */ 819 tx_time = ctime + 2 * (overhead + tx_time_data); 820 tx_time_rtscts = ctime + 2 * (overhead_rtscts + tx_time_data); 821 822 /* See how many more tries we can fit inside segment size */ 823 do { 824 /* Contention time for this try */ 825 ctime = (t_slot * cw) >> 1; 826 cw = min((cw << 1) | 1, mp->cw_max); 827 828 /* Total TX time after this try */ 829 tx_time += ctime + overhead + tx_time_data; 830 tx_time_rtscts += ctime + overhead_rtscts + tx_time_data; 831 832 if (tx_time_rtscts < mp->segment_size) 833 mrs->retry_count_rtscts++; 834 } while ((tx_time < mp->segment_size) && 835 (++mrs->retry_count < mp->max_retry)); 836 } 837 838 839 static void 840 minstrel_ht_set_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi, 841 struct ieee80211_sta_rates *ratetbl, int offset, int index) 842 { 843 const struct mcs_group *group = &minstrel_mcs_groups[index / MCS_GROUP_RATES]; 844 struct minstrel_rate_stats *mrs; 845 u8 idx; 846 u16 flags = group->flags; 847 848 mrs = minstrel_get_ratestats(mi, index); 849 if (!mrs->retry_updated) 850 minstrel_calc_retransmit(mp, mi, index); 851 852 if (mrs->prob_ewma < MINSTREL_FRAC(20, 100) || !mrs->retry_count) { 853 ratetbl->rate[offset].count = 2; 854 ratetbl->rate[offset].count_rts = 2; 855 ratetbl->rate[offset].count_cts = 2; 856 } else { 857 ratetbl->rate[offset].count = mrs->retry_count; 858 ratetbl->rate[offset].count_cts = mrs->retry_count; 859 ratetbl->rate[offset].count_rts = mrs->retry_count_rtscts; 860 } 861 862 if (index / MCS_GROUP_RATES == MINSTREL_CCK_GROUP) 863 idx = mp->cck_rates[index % ARRAY_SIZE(mp->cck_rates)]; 864 else if (flags & IEEE80211_TX_RC_VHT_MCS) 865 idx = ((group->streams - 1) << 4) | 866 ((index % MCS_GROUP_RATES) & 0xF); 867 else 868 idx = index % MCS_GROUP_RATES + (group->streams - 1) * 8; 869 870 if (offset > 0) { 871 ratetbl->rate[offset].count = ratetbl->rate[offset].count_rts; 872 flags |= IEEE80211_TX_RC_USE_RTS_CTS; 873 } 874 875 ratetbl->rate[offset].idx = idx; 876 ratetbl->rate[offset].flags = flags; 877 } 878 879 static void 880 minstrel_ht_update_rates(struct minstrel_priv *mp, struct minstrel_ht_sta *mi) 881 { 882 struct ieee80211_sta_rates *rates; 883 int i = 0; 884 885 rates = kzalloc(sizeof(*rates), GFP_ATOMIC); 886 if (!rates) 887 return; 888 889 /* Start with max_tp_rate[0] */ 890 minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_tp_rate[0]); 891 892 if (mp->hw->max_rates >= 3) { 893 /* At least 3 tx rates supported, use max_tp_rate[1] next */ 894 minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_tp_rate[1]); 895 } 896 897 if (mp->hw->max_rates >= 2) { 898 /* 899 * At least 2 tx rates supported, use max_prob_rate next */ 900 minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_prob_rate); 901 } 902 903 rates->rate[i].idx = -1; 904 rate_control_set_rates(mp->hw, mi->sta, rates); 905 } 906 907 static inline int 908 minstrel_get_duration(int index) 909 { 910 const struct mcs_group *group = &minstrel_mcs_groups[index / MCS_GROUP_RATES]; 911 return group->duration[index % MCS_GROUP_RATES]; 912 } 913 914 static int 915 minstrel_get_sample_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi) 916 { 917 struct minstrel_rate_stats *mrs; 918 struct minstrel_mcs_group_data *mg; 919 unsigned int sample_dur, sample_group, cur_max_tp_streams; 920 int sample_idx = 0; 921 922 if (mi->sample_wait > 0) { 923 mi->sample_wait--; 924 return -1; 925 } 926 927 if (!mi->sample_tries) 928 return -1; 929 930 sample_group = mi->sample_group; 931 mg = &mi->groups[sample_group]; 932 sample_idx = sample_table[mg->column][mg->index]; 933 minstrel_set_next_sample_idx(mi); 934 935 if (!(mg->supported & BIT(sample_idx))) 936 return -1; 937 938 mrs = &mg->rates[sample_idx]; 939 sample_idx += sample_group * MCS_GROUP_RATES; 940 941 /* 942 * Sampling might add some overhead (RTS, no aggregation) 943 * to the frame. Hence, don't use sampling for the currently 944 * used rates. 945 */ 946 if (sample_idx == mi->max_tp_rate[0] || 947 sample_idx == mi->max_tp_rate[1] || 948 sample_idx == mi->max_prob_rate) 949 return -1; 950 951 /* 952 * Do not sample if the probability is already higher than 95% 953 * to avoid wasting airtime. 954 */ 955 if (mrs->prob_ewma > MINSTREL_FRAC(95, 100)) 956 return -1; 957 958 /* 959 * Make sure that lower rates get sampled only occasionally, 960 * if the link is working perfectly. 961 */ 962 963 cur_max_tp_streams = minstrel_mcs_groups[mi->max_tp_rate[0] / 964 MCS_GROUP_RATES].streams; 965 sample_dur = minstrel_get_duration(sample_idx); 966 if (sample_dur >= minstrel_get_duration(mi->max_tp_rate[1]) && 967 (cur_max_tp_streams - 1 < 968 minstrel_mcs_groups[sample_group].streams || 969 sample_dur >= minstrel_get_duration(mi->max_prob_rate))) { 970 if (mrs->sample_skipped < 20) 971 return -1; 972 973 if (mi->sample_slow++ > 2) 974 return -1; 975 } 976 mi->sample_tries--; 977 978 return sample_idx; 979 } 980 981 static void 982 minstrel_ht_check_cck_shortpreamble(struct minstrel_priv *mp, 983 struct minstrel_ht_sta *mi, bool val) 984 { 985 u8 supported = mi->groups[MINSTREL_CCK_GROUP].supported; 986 987 if (!supported || !mi->cck_supported_short) 988 return; 989 990 if (supported & (mi->cck_supported_short << (val * 4))) 991 return; 992 993 supported ^= mi->cck_supported_short | (mi->cck_supported_short << 4); 994 mi->groups[MINSTREL_CCK_GROUP].supported = supported; 995 } 996 997 static void 998 minstrel_ht_get_rate(void *priv, struct ieee80211_sta *sta, void *priv_sta, 999 struct ieee80211_tx_rate_control *txrc) 1000 { 1001 const struct mcs_group *sample_group; 1002 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb); 1003 struct ieee80211_tx_rate *rate = &info->status.rates[0]; 1004 struct minstrel_ht_sta_priv *msp = priv_sta; 1005 struct minstrel_ht_sta *mi = &msp->ht; 1006 struct minstrel_priv *mp = priv; 1007 int sample_idx; 1008 1009 if (rate_control_send_low(sta, priv_sta, txrc)) 1010 return; 1011 1012 if (!msp->is_ht) 1013 return mac80211_minstrel.get_rate(priv, sta, &msp->legacy, txrc); 1014 1015 if (!(info->flags & IEEE80211_TX_CTL_AMPDU) && 1016 mi->max_prob_rate / MCS_GROUP_RATES != MINSTREL_CCK_GROUP) 1017 minstrel_aggr_check(sta, txrc->skb); 1018 1019 info->flags |= mi->tx_flags; 1020 minstrel_ht_check_cck_shortpreamble(mp, mi, txrc->short_preamble); 1021 1022 #ifdef CONFIG_MAC80211_DEBUGFS 1023 if (mp->fixed_rate_idx != -1) 1024 return; 1025 #endif 1026 1027 /* Don't use EAPOL frames for sampling on non-mrr hw */ 1028 if (mp->hw->max_rates == 1 && 1029 (info->control.flags & IEEE80211_TX_CTRL_PORT_CTRL_PROTO)) 1030 sample_idx = -1; 1031 else 1032 sample_idx = minstrel_get_sample_rate(mp, mi); 1033 1034 mi->total_packets++; 1035 1036 /* wraparound */ 1037 if (mi->total_packets == ~0) { 1038 mi->total_packets = 0; 1039 mi->sample_packets = 0; 1040 } 1041 1042 if (sample_idx < 0) 1043 return; 1044 1045 sample_group = &minstrel_mcs_groups[sample_idx / MCS_GROUP_RATES]; 1046 info->flags |= IEEE80211_TX_CTL_RATE_CTRL_PROBE; 1047 rate->count = 1; 1048 1049 if (sample_idx / MCS_GROUP_RATES == MINSTREL_CCK_GROUP) { 1050 int idx = sample_idx % ARRAY_SIZE(mp->cck_rates); 1051 rate->idx = mp->cck_rates[idx]; 1052 } else if (sample_group->flags & IEEE80211_TX_RC_VHT_MCS) { 1053 ieee80211_rate_set_vht(rate, sample_idx % MCS_GROUP_RATES, 1054 sample_group->streams); 1055 } else { 1056 rate->idx = sample_idx % MCS_GROUP_RATES + 1057 (sample_group->streams - 1) * 8; 1058 } 1059 1060 rate->flags = sample_group->flags; 1061 } 1062 1063 static void 1064 minstrel_ht_update_cck(struct minstrel_priv *mp, struct minstrel_ht_sta *mi, 1065 struct ieee80211_supported_band *sband, 1066 struct ieee80211_sta *sta) 1067 { 1068 int i; 1069 1070 if (sband->band != IEEE80211_BAND_2GHZ) 1071 return; 1072 1073 if (!ieee80211_hw_check(mp->hw, SUPPORTS_HT_CCK_RATES)) 1074 return; 1075 1076 mi->cck_supported = 0; 1077 mi->cck_supported_short = 0; 1078 for (i = 0; i < 4; i++) { 1079 if (!rate_supported(sta, sband->band, mp->cck_rates[i])) 1080 continue; 1081 1082 mi->cck_supported |= BIT(i); 1083 if (sband->bitrates[i].flags & IEEE80211_RATE_SHORT_PREAMBLE) 1084 mi->cck_supported_short |= BIT(i); 1085 } 1086 1087 mi->groups[MINSTREL_CCK_GROUP].supported = mi->cck_supported; 1088 } 1089 1090 static void 1091 minstrel_ht_update_caps(void *priv, struct ieee80211_supported_band *sband, 1092 struct cfg80211_chan_def *chandef, 1093 struct ieee80211_sta *sta, void *priv_sta) 1094 { 1095 struct minstrel_priv *mp = priv; 1096 struct minstrel_ht_sta_priv *msp = priv_sta; 1097 struct minstrel_ht_sta *mi = &msp->ht; 1098 struct ieee80211_mcs_info *mcs = &sta->ht_cap.mcs; 1099 u16 sta_cap = sta->ht_cap.cap; 1100 struct ieee80211_sta_vht_cap *vht_cap = &sta->vht_cap; 1101 int use_vht; 1102 int n_supported = 0; 1103 int ack_dur; 1104 int stbc; 1105 int i; 1106 1107 /* fall back to the old minstrel for legacy stations */ 1108 if (!sta->ht_cap.ht_supported) 1109 goto use_legacy; 1110 1111 BUILD_BUG_ON(ARRAY_SIZE(minstrel_mcs_groups) != MINSTREL_GROUPS_NB); 1112 1113 #ifdef CONFIG_MAC80211_RC_MINSTREL_VHT 1114 if (vht_cap->vht_supported) 1115 use_vht = vht_cap->vht_mcs.tx_mcs_map != cpu_to_le16(~0); 1116 else 1117 #endif 1118 use_vht = 0; 1119 1120 msp->is_ht = true; 1121 memset(mi, 0, sizeof(*mi)); 1122 1123 mi->sta = sta; 1124 mi->last_stats_update = jiffies; 1125 1126 ack_dur = ieee80211_frame_duration(sband->band, 10, 60, 1, 1, 0); 1127 mi->overhead = ieee80211_frame_duration(sband->band, 0, 60, 1, 1, 0); 1128 mi->overhead += ack_dur; 1129 mi->overhead_rtscts = mi->overhead + 2 * ack_dur; 1130 1131 mi->avg_ampdu_len = MINSTREL_FRAC(1, 1); 1132 1133 /* When using MRR, sample more on the first attempt, without delay */ 1134 if (mp->has_mrr) { 1135 mi->sample_count = 16; 1136 mi->sample_wait = 0; 1137 } else { 1138 mi->sample_count = 8; 1139 mi->sample_wait = 8; 1140 } 1141 mi->sample_tries = 4; 1142 1143 /* TODO tx_flags for vht - ATM the RC API is not fine-grained enough */ 1144 if (!use_vht) { 1145 stbc = (sta_cap & IEEE80211_HT_CAP_RX_STBC) >> 1146 IEEE80211_HT_CAP_RX_STBC_SHIFT; 1147 mi->tx_flags |= stbc << IEEE80211_TX_CTL_STBC_SHIFT; 1148 1149 if (sta_cap & IEEE80211_HT_CAP_LDPC_CODING) 1150 mi->tx_flags |= IEEE80211_TX_CTL_LDPC; 1151 } 1152 1153 for (i = 0; i < ARRAY_SIZE(mi->groups); i++) { 1154 u32 gflags = minstrel_mcs_groups[i].flags; 1155 int bw, nss; 1156 1157 mi->groups[i].supported = 0; 1158 if (i == MINSTREL_CCK_GROUP) { 1159 minstrel_ht_update_cck(mp, mi, sband, sta); 1160 continue; 1161 } 1162 1163 if (gflags & IEEE80211_TX_RC_SHORT_GI) { 1164 if (gflags & IEEE80211_TX_RC_40_MHZ_WIDTH) { 1165 if (!(sta_cap & IEEE80211_HT_CAP_SGI_40)) 1166 continue; 1167 } else { 1168 if (!(sta_cap & IEEE80211_HT_CAP_SGI_20)) 1169 continue; 1170 } 1171 } 1172 1173 if (gflags & IEEE80211_TX_RC_40_MHZ_WIDTH && 1174 sta->bandwidth < IEEE80211_STA_RX_BW_40) 1175 continue; 1176 1177 nss = minstrel_mcs_groups[i].streams; 1178 1179 /* Mark MCS > 7 as unsupported if STA is in static SMPS mode */ 1180 if (sta->smps_mode == IEEE80211_SMPS_STATIC && nss > 1) 1181 continue; 1182 1183 /* HT rate */ 1184 if (gflags & IEEE80211_TX_RC_MCS) { 1185 #ifdef CONFIG_MAC80211_RC_MINSTREL_VHT 1186 if (use_vht && minstrel_vht_only) 1187 continue; 1188 #endif 1189 mi->groups[i].supported = mcs->rx_mask[nss - 1]; 1190 if (mi->groups[i].supported) 1191 n_supported++; 1192 continue; 1193 } 1194 1195 /* VHT rate */ 1196 if (!vht_cap->vht_supported || 1197 WARN_ON(!(gflags & IEEE80211_TX_RC_VHT_MCS)) || 1198 WARN_ON(gflags & IEEE80211_TX_RC_160_MHZ_WIDTH)) 1199 continue; 1200 1201 if (gflags & IEEE80211_TX_RC_80_MHZ_WIDTH) { 1202 if (sta->bandwidth < IEEE80211_STA_RX_BW_80 || 1203 ((gflags & IEEE80211_TX_RC_SHORT_GI) && 1204 !(vht_cap->cap & IEEE80211_VHT_CAP_SHORT_GI_80))) { 1205 continue; 1206 } 1207 } 1208 1209 if (gflags & IEEE80211_TX_RC_40_MHZ_WIDTH) 1210 bw = BW_40; 1211 else if (gflags & IEEE80211_TX_RC_80_MHZ_WIDTH) 1212 bw = BW_80; 1213 else 1214 bw = BW_20; 1215 1216 mi->groups[i].supported = minstrel_get_valid_vht_rates(bw, nss, 1217 vht_cap->vht_mcs.tx_mcs_map); 1218 1219 if (mi->groups[i].supported) 1220 n_supported++; 1221 } 1222 1223 if (!n_supported) 1224 goto use_legacy; 1225 1226 /* create an initial rate table with the lowest supported rates */ 1227 minstrel_ht_update_stats(mp, mi); 1228 minstrel_ht_update_rates(mp, mi); 1229 1230 return; 1231 1232 use_legacy: 1233 msp->is_ht = false; 1234 memset(&msp->legacy, 0, sizeof(msp->legacy)); 1235 msp->legacy.r = msp->ratelist; 1236 msp->legacy.sample_table = msp->sample_table; 1237 return mac80211_minstrel.rate_init(priv, sband, chandef, sta, 1238 &msp->legacy); 1239 } 1240 1241 static void 1242 minstrel_ht_rate_init(void *priv, struct ieee80211_supported_band *sband, 1243 struct cfg80211_chan_def *chandef, 1244 struct ieee80211_sta *sta, void *priv_sta) 1245 { 1246 minstrel_ht_update_caps(priv, sband, chandef, sta, priv_sta); 1247 } 1248 1249 static void 1250 minstrel_ht_rate_update(void *priv, struct ieee80211_supported_band *sband, 1251 struct cfg80211_chan_def *chandef, 1252 struct ieee80211_sta *sta, void *priv_sta, 1253 u32 changed) 1254 { 1255 minstrel_ht_update_caps(priv, sband, chandef, sta, priv_sta); 1256 } 1257 1258 static void * 1259 minstrel_ht_alloc_sta(void *priv, struct ieee80211_sta *sta, gfp_t gfp) 1260 { 1261 struct ieee80211_supported_band *sband; 1262 struct minstrel_ht_sta_priv *msp; 1263 struct minstrel_priv *mp = priv; 1264 struct ieee80211_hw *hw = mp->hw; 1265 int max_rates = 0; 1266 int i; 1267 1268 for (i = 0; i < IEEE80211_NUM_BANDS; i++) { 1269 sband = hw->wiphy->bands[i]; 1270 if (sband && sband->n_bitrates > max_rates) 1271 max_rates = sband->n_bitrates; 1272 } 1273 1274 msp = kzalloc(sizeof(*msp), gfp); 1275 if (!msp) 1276 return NULL; 1277 1278 msp->ratelist = kzalloc(sizeof(struct minstrel_rate) * max_rates, gfp); 1279 if (!msp->ratelist) 1280 goto error; 1281 1282 msp->sample_table = kmalloc(SAMPLE_COLUMNS * max_rates, gfp); 1283 if (!msp->sample_table) 1284 goto error1; 1285 1286 return msp; 1287 1288 error1: 1289 kfree(msp->ratelist); 1290 error: 1291 kfree(msp); 1292 return NULL; 1293 } 1294 1295 static void 1296 minstrel_ht_free_sta(void *priv, struct ieee80211_sta *sta, void *priv_sta) 1297 { 1298 struct minstrel_ht_sta_priv *msp = priv_sta; 1299 1300 kfree(msp->sample_table); 1301 kfree(msp->ratelist); 1302 kfree(msp); 1303 } 1304 1305 static void * 1306 minstrel_ht_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir) 1307 { 1308 return mac80211_minstrel.alloc(hw, debugfsdir); 1309 } 1310 1311 static void 1312 minstrel_ht_free(void *priv) 1313 { 1314 mac80211_minstrel.free(priv); 1315 } 1316 1317 static u32 minstrel_ht_get_expected_throughput(void *priv_sta) 1318 { 1319 struct minstrel_ht_sta_priv *msp = priv_sta; 1320 struct minstrel_ht_sta *mi = &msp->ht; 1321 int i, j, prob, tp_avg; 1322 1323 if (!msp->is_ht) 1324 return mac80211_minstrel.get_expected_throughput(priv_sta); 1325 1326 i = mi->max_tp_rate[0] / MCS_GROUP_RATES; 1327 j = mi->max_tp_rate[0] % MCS_GROUP_RATES; 1328 prob = mi->groups[i].rates[j].prob_ewma; 1329 1330 /* convert tp_avg from pkt per second in kbps */ 1331 tp_avg = minstrel_ht_get_tp_avg(mi, i, j, prob) * AVG_PKT_SIZE * 8 / 1024; 1332 1333 return tp_avg; 1334 } 1335 1336 static const struct rate_control_ops mac80211_minstrel_ht = { 1337 .name = "minstrel_ht", 1338 .tx_status_noskb = minstrel_ht_tx_status, 1339 .get_rate = minstrel_ht_get_rate, 1340 .rate_init = minstrel_ht_rate_init, 1341 .rate_update = minstrel_ht_rate_update, 1342 .alloc_sta = minstrel_ht_alloc_sta, 1343 .free_sta = minstrel_ht_free_sta, 1344 .alloc = minstrel_ht_alloc, 1345 .free = minstrel_ht_free, 1346 #ifdef CONFIG_MAC80211_DEBUGFS 1347 .add_sta_debugfs = minstrel_ht_add_sta_debugfs, 1348 .remove_sta_debugfs = minstrel_ht_remove_sta_debugfs, 1349 #endif 1350 .get_expected_throughput = minstrel_ht_get_expected_throughput, 1351 }; 1352 1353 1354 static void __init init_sample_table(void) 1355 { 1356 int col, i, new_idx; 1357 u8 rnd[MCS_GROUP_RATES]; 1358 1359 memset(sample_table, 0xff, sizeof(sample_table)); 1360 for (col = 0; col < SAMPLE_COLUMNS; col++) { 1361 prandom_bytes(rnd, sizeof(rnd)); 1362 for (i = 0; i < MCS_GROUP_RATES; i++) { 1363 new_idx = (i + rnd[i]) % MCS_GROUP_RATES; 1364 while (sample_table[col][new_idx] != 0xff) 1365 new_idx = (new_idx + 1) % MCS_GROUP_RATES; 1366 1367 sample_table[col][new_idx] = i; 1368 } 1369 } 1370 } 1371 1372 int __init 1373 rc80211_minstrel_ht_init(void) 1374 { 1375 init_sample_table(); 1376 return ieee80211_rate_control_register(&mac80211_minstrel_ht); 1377 } 1378 1379 void 1380 rc80211_minstrel_ht_exit(void) 1381 { 1382 ieee80211_rate_control_unregister(&mac80211_minstrel_ht); 1383 } 1384