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 max_gpr_group = mg->max_group_prob_rate / MCS_GROUP_RATES; 418 max_gpr_idx = mg->max_group_prob_rate % MCS_GROUP_RATES; 419 max_gpr_prob = mi->groups[max_gpr_group].rates[max_gpr_idx].prob_ewma; 420 421 if (mrs->prob_ewma > MINSTREL_FRAC(75, 100)) { 422 cur_tp_avg = minstrel_ht_get_tp_avg(mi, cur_group, cur_idx, 423 mrs->prob_ewma); 424 if (cur_tp_avg > tmp_tp_avg) 425 mi->max_prob_rate = index; 426 427 max_gpr_tp_avg = minstrel_ht_get_tp_avg(mi, max_gpr_group, 428 max_gpr_idx, 429 max_gpr_prob); 430 if (cur_tp_avg > max_gpr_tp_avg) 431 mg->max_group_prob_rate = index; 432 } else { 433 if (mrs->prob_ewma > tmp_prob) 434 mi->max_prob_rate = index; 435 if (mrs->prob_ewma > max_gpr_prob) 436 mg->max_group_prob_rate = index; 437 } 438 } 439 440 441 /* 442 * Assign new rate set per sta and use CCK rates only if the fastest 443 * rate (max_tp_rate[0]) is from CCK group. This prohibits such sorted 444 * rate sets where MCS and CCK rates are mixed, because CCK rates can 445 * not use aggregation. 446 */ 447 static void 448 minstrel_ht_assign_best_tp_rates(struct minstrel_ht_sta *mi, 449 u16 tmp_mcs_tp_rate[MAX_THR_RATES], 450 u16 tmp_cck_tp_rate[MAX_THR_RATES]) 451 { 452 unsigned int tmp_group, tmp_idx, tmp_cck_tp, tmp_mcs_tp, tmp_prob; 453 int i; 454 455 tmp_group = tmp_cck_tp_rate[0] / MCS_GROUP_RATES; 456 tmp_idx = tmp_cck_tp_rate[0] % MCS_GROUP_RATES; 457 tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_ewma; 458 tmp_cck_tp = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx, tmp_prob); 459 460 tmp_group = tmp_mcs_tp_rate[0] / MCS_GROUP_RATES; 461 tmp_idx = tmp_mcs_tp_rate[0] % MCS_GROUP_RATES; 462 tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_ewma; 463 tmp_mcs_tp = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx, tmp_prob); 464 465 if (tmp_cck_tp > tmp_mcs_tp) { 466 for(i = 0; i < MAX_THR_RATES; i++) { 467 minstrel_ht_sort_best_tp_rates(mi, tmp_cck_tp_rate[i], 468 tmp_mcs_tp_rate); 469 } 470 } 471 472 } 473 474 /* 475 * Try to increase robustness of max_prob rate by decrease number of 476 * streams if possible. 477 */ 478 static inline void 479 minstrel_ht_prob_rate_reduce_streams(struct minstrel_ht_sta *mi) 480 { 481 struct minstrel_mcs_group_data *mg; 482 int tmp_max_streams, group, tmp_idx, tmp_prob; 483 int tmp_tp = 0; 484 485 tmp_max_streams = minstrel_mcs_groups[mi->max_tp_rate[0] / 486 MCS_GROUP_RATES].streams; 487 for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) { 488 mg = &mi->groups[group]; 489 if (!mg->supported || group == MINSTREL_CCK_GROUP) 490 continue; 491 492 tmp_idx = mg->max_group_prob_rate % MCS_GROUP_RATES; 493 tmp_prob = mi->groups[group].rates[tmp_idx].prob_ewma; 494 495 if (tmp_tp < minstrel_ht_get_tp_avg(mi, group, tmp_idx, tmp_prob) && 496 (minstrel_mcs_groups[group].streams < tmp_max_streams)) { 497 mi->max_prob_rate = mg->max_group_prob_rate; 498 tmp_tp = minstrel_ht_get_tp_avg(mi, group, 499 tmp_idx, 500 tmp_prob); 501 } 502 } 503 } 504 505 /* 506 * Update rate statistics and select new primary rates 507 * 508 * Rules for rate selection: 509 * - max_prob_rate must use only one stream, as a tradeoff between delivery 510 * probability and throughput during strong fluctuations 511 * - as long as the max prob rate has a probability of more than 75%, pick 512 * higher throughput rates, even if the probablity is a bit lower 513 */ 514 static void 515 minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi) 516 { 517 struct minstrel_mcs_group_data *mg; 518 struct minstrel_rate_stats *mrs; 519 int group, i, j, cur_prob; 520 u16 tmp_mcs_tp_rate[MAX_THR_RATES], tmp_group_tp_rate[MAX_THR_RATES]; 521 u16 tmp_cck_tp_rate[MAX_THR_RATES], index; 522 523 if (mi->ampdu_packets > 0) { 524 mi->avg_ampdu_len = minstrel_ewma(mi->avg_ampdu_len, 525 MINSTREL_FRAC(mi->ampdu_len, mi->ampdu_packets), EWMA_LEVEL); 526 mi->ampdu_len = 0; 527 mi->ampdu_packets = 0; 528 } 529 530 mi->sample_slow = 0; 531 mi->sample_count = 0; 532 533 /* Initialize global rate indexes */ 534 for(j = 0; j < MAX_THR_RATES; j++){ 535 tmp_mcs_tp_rate[j] = 0; 536 tmp_cck_tp_rate[j] = 0; 537 } 538 539 /* Find best rate sets within all MCS groups*/ 540 for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) { 541 542 mg = &mi->groups[group]; 543 if (!mg->supported) 544 continue; 545 546 mi->sample_count++; 547 548 /* (re)Initialize group rate indexes */ 549 for(j = 0; j < MAX_THR_RATES; j++) 550 tmp_group_tp_rate[j] = group; 551 552 for (i = 0; i < MCS_GROUP_RATES; i++) { 553 if (!(mg->supported & BIT(i))) 554 continue; 555 556 index = MCS_GROUP_RATES * group + i; 557 558 mrs = &mg->rates[i]; 559 mrs->retry_updated = false; 560 minstrel_calc_rate_stats(mrs); 561 cur_prob = mrs->prob_ewma; 562 563 if (minstrel_ht_get_tp_avg(mi, group, i, cur_prob) == 0) 564 continue; 565 566 /* Find max throughput rate set */ 567 if (group != MINSTREL_CCK_GROUP) { 568 minstrel_ht_sort_best_tp_rates(mi, index, 569 tmp_mcs_tp_rate); 570 } else if (group == MINSTREL_CCK_GROUP) { 571 minstrel_ht_sort_best_tp_rates(mi, index, 572 tmp_cck_tp_rate); 573 } 574 575 /* Find max throughput rate set within a group */ 576 minstrel_ht_sort_best_tp_rates(mi, index, 577 tmp_group_tp_rate); 578 579 /* Find max probability rate per group and global */ 580 minstrel_ht_set_best_prob_rate(mi, index); 581 } 582 583 memcpy(mg->max_group_tp_rate, tmp_group_tp_rate, 584 sizeof(mg->max_group_tp_rate)); 585 } 586 587 /* Assign new rate set per sta */ 588 minstrel_ht_assign_best_tp_rates(mi, tmp_mcs_tp_rate, tmp_cck_tp_rate); 589 memcpy(mi->max_tp_rate, tmp_mcs_tp_rate, sizeof(mi->max_tp_rate)); 590 591 /* Try to increase robustness of max_prob_rate*/ 592 minstrel_ht_prob_rate_reduce_streams(mi); 593 594 /* try to sample all available rates during each interval */ 595 mi->sample_count *= 8; 596 597 #ifdef CONFIG_MAC80211_DEBUGFS 598 /* use fixed index if set */ 599 if (mp->fixed_rate_idx != -1) { 600 for (i = 0; i < 4; i++) 601 mi->max_tp_rate[i] = mp->fixed_rate_idx; 602 mi->max_prob_rate = mp->fixed_rate_idx; 603 } 604 #endif 605 606 /* Reset update timer */ 607 mi->last_stats_update = jiffies; 608 } 609 610 static bool 611 minstrel_ht_txstat_valid(struct minstrel_priv *mp, struct ieee80211_tx_rate *rate) 612 { 613 if (rate->idx < 0) 614 return false; 615 616 if (!rate->count) 617 return false; 618 619 if (rate->flags & IEEE80211_TX_RC_MCS || 620 rate->flags & IEEE80211_TX_RC_VHT_MCS) 621 return true; 622 623 return rate->idx == mp->cck_rates[0] || 624 rate->idx == mp->cck_rates[1] || 625 rate->idx == mp->cck_rates[2] || 626 rate->idx == mp->cck_rates[3]; 627 } 628 629 static void 630 minstrel_set_next_sample_idx(struct minstrel_ht_sta *mi) 631 { 632 struct minstrel_mcs_group_data *mg; 633 634 for (;;) { 635 mi->sample_group++; 636 mi->sample_group %= ARRAY_SIZE(minstrel_mcs_groups); 637 mg = &mi->groups[mi->sample_group]; 638 639 if (!mg->supported) 640 continue; 641 642 if (++mg->index >= MCS_GROUP_RATES) { 643 mg->index = 0; 644 if (++mg->column >= ARRAY_SIZE(sample_table)) 645 mg->column = 0; 646 } 647 break; 648 } 649 } 650 651 static void 652 minstrel_downgrade_rate(struct minstrel_ht_sta *mi, u16 *idx, bool primary) 653 { 654 int group, orig_group; 655 656 orig_group = group = *idx / MCS_GROUP_RATES; 657 while (group > 0) { 658 group--; 659 660 if (!mi->groups[group].supported) 661 continue; 662 663 if (minstrel_mcs_groups[group].streams > 664 minstrel_mcs_groups[orig_group].streams) 665 continue; 666 667 if (primary) 668 *idx = mi->groups[group].max_group_tp_rate[0]; 669 else 670 *idx = mi->groups[group].max_group_tp_rate[1]; 671 break; 672 } 673 } 674 675 static void 676 minstrel_aggr_check(struct ieee80211_sta *pubsta, struct sk_buff *skb) 677 { 678 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 679 struct sta_info *sta = container_of(pubsta, struct sta_info, sta); 680 u16 tid; 681 682 if (skb_get_queue_mapping(skb) == IEEE80211_AC_VO) 683 return; 684 685 if (unlikely(!ieee80211_is_data_qos(hdr->frame_control))) 686 return; 687 688 if (unlikely(skb->protocol == cpu_to_be16(ETH_P_PAE))) 689 return; 690 691 tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK; 692 if (likely(sta->ampdu_mlme.tid_tx[tid])) 693 return; 694 695 ieee80211_start_tx_ba_session(pubsta, tid, 0); 696 } 697 698 static void 699 minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband, 700 struct ieee80211_sta *sta, void *priv_sta, 701 struct ieee80211_tx_info *info) 702 { 703 struct minstrel_ht_sta_priv *msp = priv_sta; 704 struct minstrel_ht_sta *mi = &msp->ht; 705 struct ieee80211_tx_rate *ar = info->status.rates; 706 struct minstrel_rate_stats *rate, *rate2; 707 struct minstrel_priv *mp = priv; 708 bool last, update = false; 709 int i; 710 711 if (!msp->is_ht) 712 return mac80211_minstrel.tx_status_noskb(priv, sband, sta, 713 &msp->legacy, info); 714 715 /* This packet was aggregated but doesn't carry status info */ 716 if ((info->flags & IEEE80211_TX_CTL_AMPDU) && 717 !(info->flags & IEEE80211_TX_STAT_AMPDU)) 718 return; 719 720 if (!(info->flags & IEEE80211_TX_STAT_AMPDU)) { 721 info->status.ampdu_ack_len = 722 (info->flags & IEEE80211_TX_STAT_ACK ? 1 : 0); 723 info->status.ampdu_len = 1; 724 } 725 726 mi->ampdu_packets++; 727 mi->ampdu_len += info->status.ampdu_len; 728 729 if (!mi->sample_wait && !mi->sample_tries && mi->sample_count > 0) { 730 mi->sample_wait = 16 + 2 * MINSTREL_TRUNC(mi->avg_ampdu_len); 731 mi->sample_tries = 1; 732 mi->sample_count--; 733 } 734 735 if (info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE) 736 mi->sample_packets += info->status.ampdu_len; 737 738 last = !minstrel_ht_txstat_valid(mp, &ar[0]); 739 for (i = 0; !last; i++) { 740 last = (i == IEEE80211_TX_MAX_RATES - 1) || 741 !minstrel_ht_txstat_valid(mp, &ar[i + 1]); 742 743 rate = minstrel_ht_get_stats(mp, mi, &ar[i]); 744 745 if (last) 746 rate->success += info->status.ampdu_ack_len; 747 748 rate->attempts += ar[i].count * info->status.ampdu_len; 749 } 750 751 /* 752 * check for sudden death of spatial multiplexing, 753 * downgrade to a lower number of streams if necessary. 754 */ 755 rate = minstrel_get_ratestats(mi, mi->max_tp_rate[0]); 756 if (rate->attempts > 30 && 757 MINSTREL_FRAC(rate->success, rate->attempts) < 758 MINSTREL_FRAC(20, 100)) { 759 minstrel_downgrade_rate(mi, &mi->max_tp_rate[0], true); 760 update = true; 761 } 762 763 rate2 = minstrel_get_ratestats(mi, mi->max_tp_rate[1]); 764 if (rate2->attempts > 30 && 765 MINSTREL_FRAC(rate2->success, rate2->attempts) < 766 MINSTREL_FRAC(20, 100)) { 767 minstrel_downgrade_rate(mi, &mi->max_tp_rate[1], false); 768 update = true; 769 } 770 771 if (time_after(jiffies, mi->last_stats_update + 772 (mp->update_interval / 2 * HZ) / 1000)) { 773 update = true; 774 minstrel_ht_update_stats(mp, mi); 775 } 776 777 if (update) 778 minstrel_ht_update_rates(mp, mi); 779 } 780 781 static void 782 minstrel_calc_retransmit(struct minstrel_priv *mp, struct minstrel_ht_sta *mi, 783 int index) 784 { 785 struct minstrel_rate_stats *mrs; 786 const struct mcs_group *group; 787 unsigned int tx_time, tx_time_rtscts, tx_time_data; 788 unsigned int cw = mp->cw_min; 789 unsigned int ctime = 0; 790 unsigned int t_slot = 9; /* FIXME */ 791 unsigned int ampdu_len = MINSTREL_TRUNC(mi->avg_ampdu_len); 792 unsigned int overhead = 0, overhead_rtscts = 0; 793 794 mrs = minstrel_get_ratestats(mi, index); 795 if (mrs->prob_ewma < MINSTREL_FRAC(1, 10)) { 796 mrs->retry_count = 1; 797 mrs->retry_count_rtscts = 1; 798 return; 799 } 800 801 mrs->retry_count = 2; 802 mrs->retry_count_rtscts = 2; 803 mrs->retry_updated = true; 804 805 group = &minstrel_mcs_groups[index / MCS_GROUP_RATES]; 806 tx_time_data = group->duration[index % MCS_GROUP_RATES] * ampdu_len / 1000; 807 808 /* Contention time for first 2 tries */ 809 ctime = (t_slot * cw) >> 1; 810 cw = min((cw << 1) | 1, mp->cw_max); 811 ctime += (t_slot * cw) >> 1; 812 cw = min((cw << 1) | 1, mp->cw_max); 813 814 if (index / MCS_GROUP_RATES != MINSTREL_CCK_GROUP) { 815 overhead = mi->overhead; 816 overhead_rtscts = mi->overhead_rtscts; 817 } 818 819 /* Total TX time for data and Contention after first 2 tries */ 820 tx_time = ctime + 2 * (overhead + tx_time_data); 821 tx_time_rtscts = ctime + 2 * (overhead_rtscts + tx_time_data); 822 823 /* See how many more tries we can fit inside segment size */ 824 do { 825 /* Contention time for this try */ 826 ctime = (t_slot * cw) >> 1; 827 cw = min((cw << 1) | 1, mp->cw_max); 828 829 /* Total TX time after this try */ 830 tx_time += ctime + overhead + tx_time_data; 831 tx_time_rtscts += ctime + overhead_rtscts + tx_time_data; 832 833 if (tx_time_rtscts < mp->segment_size) 834 mrs->retry_count_rtscts++; 835 } while ((tx_time < mp->segment_size) && 836 (++mrs->retry_count < mp->max_retry)); 837 } 838 839 840 static void 841 minstrel_ht_set_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi, 842 struct ieee80211_sta_rates *ratetbl, int offset, int index) 843 { 844 const struct mcs_group *group = &minstrel_mcs_groups[index / MCS_GROUP_RATES]; 845 struct minstrel_rate_stats *mrs; 846 u8 idx; 847 u16 flags = group->flags; 848 849 mrs = minstrel_get_ratestats(mi, index); 850 if (!mrs->retry_updated) 851 minstrel_calc_retransmit(mp, mi, index); 852 853 if (mrs->prob_ewma < MINSTREL_FRAC(20, 100) || !mrs->retry_count) { 854 ratetbl->rate[offset].count = 2; 855 ratetbl->rate[offset].count_rts = 2; 856 ratetbl->rate[offset].count_cts = 2; 857 } else { 858 ratetbl->rate[offset].count = mrs->retry_count; 859 ratetbl->rate[offset].count_cts = mrs->retry_count; 860 ratetbl->rate[offset].count_rts = mrs->retry_count_rtscts; 861 } 862 863 if (index / MCS_GROUP_RATES == MINSTREL_CCK_GROUP) 864 idx = mp->cck_rates[index % ARRAY_SIZE(mp->cck_rates)]; 865 else if (flags & IEEE80211_TX_RC_VHT_MCS) 866 idx = ((group->streams - 1) << 4) | 867 ((index % MCS_GROUP_RATES) & 0xF); 868 else 869 idx = index % MCS_GROUP_RATES + (group->streams - 1) * 8; 870 871 /* enable RTS/CTS if needed: 872 * - if station is in dynamic SMPS (and streams > 1) 873 * - for fallback rates, to increase chances of getting through 874 */ 875 if (offset > 0 || 876 (mi->sta->smps_mode == IEEE80211_SMPS_DYNAMIC && 877 group->streams > 1)) { 878 ratetbl->rate[offset].count = ratetbl->rate[offset].count_rts; 879 flags |= IEEE80211_TX_RC_USE_RTS_CTS; 880 } 881 882 ratetbl->rate[offset].idx = idx; 883 ratetbl->rate[offset].flags = flags; 884 } 885 886 static void 887 minstrel_ht_update_rates(struct minstrel_priv *mp, struct minstrel_ht_sta *mi) 888 { 889 struct ieee80211_sta_rates *rates; 890 int i = 0; 891 892 rates = kzalloc(sizeof(*rates), GFP_ATOMIC); 893 if (!rates) 894 return; 895 896 /* Start with max_tp_rate[0] */ 897 minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_tp_rate[0]); 898 899 if (mp->hw->max_rates >= 3) { 900 /* At least 3 tx rates supported, use max_tp_rate[1] next */ 901 minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_tp_rate[1]); 902 } 903 904 if (mp->hw->max_rates >= 2) { 905 /* 906 * At least 2 tx rates supported, use max_prob_rate next */ 907 minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_prob_rate); 908 } 909 910 rates->rate[i].idx = -1; 911 rate_control_set_rates(mp->hw, mi->sta, rates); 912 } 913 914 static inline int 915 minstrel_get_duration(int index) 916 { 917 const struct mcs_group *group = &minstrel_mcs_groups[index / MCS_GROUP_RATES]; 918 return group->duration[index % MCS_GROUP_RATES]; 919 } 920 921 static int 922 minstrel_get_sample_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi) 923 { 924 struct minstrel_rate_stats *mrs; 925 struct minstrel_mcs_group_data *mg; 926 unsigned int sample_dur, sample_group, cur_max_tp_streams; 927 int sample_idx = 0; 928 929 if (mi->sample_wait > 0) { 930 mi->sample_wait--; 931 return -1; 932 } 933 934 if (!mi->sample_tries) 935 return -1; 936 937 sample_group = mi->sample_group; 938 mg = &mi->groups[sample_group]; 939 sample_idx = sample_table[mg->column][mg->index]; 940 minstrel_set_next_sample_idx(mi); 941 942 if (!(mg->supported & BIT(sample_idx))) 943 return -1; 944 945 mrs = &mg->rates[sample_idx]; 946 sample_idx += sample_group * MCS_GROUP_RATES; 947 948 /* 949 * Sampling might add some overhead (RTS, no aggregation) 950 * to the frame. Hence, don't use sampling for the currently 951 * used rates. 952 */ 953 if (sample_idx == mi->max_tp_rate[0] || 954 sample_idx == mi->max_tp_rate[1] || 955 sample_idx == mi->max_prob_rate) 956 return -1; 957 958 /* 959 * Do not sample if the probability is already higher than 95% 960 * to avoid wasting airtime. 961 */ 962 if (mrs->prob_ewma > MINSTREL_FRAC(95, 100)) 963 return -1; 964 965 /* 966 * Make sure that lower rates get sampled only occasionally, 967 * if the link is working perfectly. 968 */ 969 970 cur_max_tp_streams = minstrel_mcs_groups[mi->max_tp_rate[0] / 971 MCS_GROUP_RATES].streams; 972 sample_dur = minstrel_get_duration(sample_idx); 973 if (sample_dur >= minstrel_get_duration(mi->max_tp_rate[1]) && 974 (cur_max_tp_streams - 1 < 975 minstrel_mcs_groups[sample_group].streams || 976 sample_dur >= minstrel_get_duration(mi->max_prob_rate))) { 977 if (mrs->sample_skipped < 20) 978 return -1; 979 980 if (mi->sample_slow++ > 2) 981 return -1; 982 } 983 mi->sample_tries--; 984 985 return sample_idx; 986 } 987 988 static void 989 minstrel_ht_check_cck_shortpreamble(struct minstrel_priv *mp, 990 struct minstrel_ht_sta *mi, bool val) 991 { 992 u8 supported = mi->groups[MINSTREL_CCK_GROUP].supported; 993 994 if (!supported || !mi->cck_supported_short) 995 return; 996 997 if (supported & (mi->cck_supported_short << (val * 4))) 998 return; 999 1000 supported ^= mi->cck_supported_short | (mi->cck_supported_short << 4); 1001 mi->groups[MINSTREL_CCK_GROUP].supported = supported; 1002 } 1003 1004 static void 1005 minstrel_ht_get_rate(void *priv, struct ieee80211_sta *sta, void *priv_sta, 1006 struct ieee80211_tx_rate_control *txrc) 1007 { 1008 const struct mcs_group *sample_group; 1009 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb); 1010 struct ieee80211_tx_rate *rate = &info->status.rates[0]; 1011 struct minstrel_ht_sta_priv *msp = priv_sta; 1012 struct minstrel_ht_sta *mi = &msp->ht; 1013 struct minstrel_priv *mp = priv; 1014 int sample_idx; 1015 1016 if (rate_control_send_low(sta, priv_sta, txrc)) 1017 return; 1018 1019 if (!msp->is_ht) 1020 return mac80211_minstrel.get_rate(priv, sta, &msp->legacy, txrc); 1021 1022 if (!(info->flags & IEEE80211_TX_CTL_AMPDU) && 1023 mi->max_prob_rate / MCS_GROUP_RATES != MINSTREL_CCK_GROUP) 1024 minstrel_aggr_check(sta, txrc->skb); 1025 1026 info->flags |= mi->tx_flags; 1027 minstrel_ht_check_cck_shortpreamble(mp, mi, txrc->short_preamble); 1028 1029 #ifdef CONFIG_MAC80211_DEBUGFS 1030 if (mp->fixed_rate_idx != -1) 1031 return; 1032 #endif 1033 1034 /* Don't use EAPOL frames for sampling on non-mrr hw */ 1035 if (mp->hw->max_rates == 1 && 1036 (info->control.flags & IEEE80211_TX_CTRL_PORT_CTRL_PROTO)) 1037 sample_idx = -1; 1038 else 1039 sample_idx = minstrel_get_sample_rate(mp, mi); 1040 1041 mi->total_packets++; 1042 1043 /* wraparound */ 1044 if (mi->total_packets == ~0) { 1045 mi->total_packets = 0; 1046 mi->sample_packets = 0; 1047 } 1048 1049 if (sample_idx < 0) 1050 return; 1051 1052 sample_group = &minstrel_mcs_groups[sample_idx / MCS_GROUP_RATES]; 1053 info->flags |= IEEE80211_TX_CTL_RATE_CTRL_PROBE; 1054 rate->count = 1; 1055 1056 if (sample_idx / MCS_GROUP_RATES == MINSTREL_CCK_GROUP) { 1057 int idx = sample_idx % ARRAY_SIZE(mp->cck_rates); 1058 rate->idx = mp->cck_rates[idx]; 1059 } else if (sample_group->flags & IEEE80211_TX_RC_VHT_MCS) { 1060 ieee80211_rate_set_vht(rate, sample_idx % MCS_GROUP_RATES, 1061 sample_group->streams); 1062 } else { 1063 rate->idx = sample_idx % MCS_GROUP_RATES + 1064 (sample_group->streams - 1) * 8; 1065 } 1066 1067 rate->flags = sample_group->flags; 1068 } 1069 1070 static void 1071 minstrel_ht_update_cck(struct minstrel_priv *mp, struct minstrel_ht_sta *mi, 1072 struct ieee80211_supported_band *sband, 1073 struct ieee80211_sta *sta) 1074 { 1075 int i; 1076 1077 if (sband->band != IEEE80211_BAND_2GHZ) 1078 return; 1079 1080 if (!ieee80211_hw_check(mp->hw, SUPPORTS_HT_CCK_RATES)) 1081 return; 1082 1083 mi->cck_supported = 0; 1084 mi->cck_supported_short = 0; 1085 for (i = 0; i < 4; i++) { 1086 if (!rate_supported(sta, sband->band, mp->cck_rates[i])) 1087 continue; 1088 1089 mi->cck_supported |= BIT(i); 1090 if (sband->bitrates[i].flags & IEEE80211_RATE_SHORT_PREAMBLE) 1091 mi->cck_supported_short |= BIT(i); 1092 } 1093 1094 mi->groups[MINSTREL_CCK_GROUP].supported = mi->cck_supported; 1095 } 1096 1097 static void 1098 minstrel_ht_update_caps(void *priv, struct ieee80211_supported_band *sband, 1099 struct cfg80211_chan_def *chandef, 1100 struct ieee80211_sta *sta, void *priv_sta) 1101 { 1102 struct minstrel_priv *mp = priv; 1103 struct minstrel_ht_sta_priv *msp = priv_sta; 1104 struct minstrel_ht_sta *mi = &msp->ht; 1105 struct ieee80211_mcs_info *mcs = &sta->ht_cap.mcs; 1106 u16 sta_cap = sta->ht_cap.cap; 1107 struct ieee80211_sta_vht_cap *vht_cap = &sta->vht_cap; 1108 int use_vht; 1109 int n_supported = 0; 1110 int ack_dur; 1111 int stbc; 1112 int i; 1113 1114 /* fall back to the old minstrel for legacy stations */ 1115 if (!sta->ht_cap.ht_supported) 1116 goto use_legacy; 1117 1118 BUILD_BUG_ON(ARRAY_SIZE(minstrel_mcs_groups) != MINSTREL_GROUPS_NB); 1119 1120 #ifdef CONFIG_MAC80211_RC_MINSTREL_VHT 1121 if (vht_cap->vht_supported) 1122 use_vht = vht_cap->vht_mcs.tx_mcs_map != cpu_to_le16(~0); 1123 else 1124 #endif 1125 use_vht = 0; 1126 1127 msp->is_ht = true; 1128 memset(mi, 0, sizeof(*mi)); 1129 1130 mi->sta = sta; 1131 mi->last_stats_update = jiffies; 1132 1133 ack_dur = ieee80211_frame_duration(sband->band, 10, 60, 1, 1, 0); 1134 mi->overhead = ieee80211_frame_duration(sband->band, 0, 60, 1, 1, 0); 1135 mi->overhead += ack_dur; 1136 mi->overhead_rtscts = mi->overhead + 2 * ack_dur; 1137 1138 mi->avg_ampdu_len = MINSTREL_FRAC(1, 1); 1139 1140 /* When using MRR, sample more on the first attempt, without delay */ 1141 if (mp->has_mrr) { 1142 mi->sample_count = 16; 1143 mi->sample_wait = 0; 1144 } else { 1145 mi->sample_count = 8; 1146 mi->sample_wait = 8; 1147 } 1148 mi->sample_tries = 4; 1149 1150 /* TODO tx_flags for vht - ATM the RC API is not fine-grained enough */ 1151 if (!use_vht) { 1152 stbc = (sta_cap & IEEE80211_HT_CAP_RX_STBC) >> 1153 IEEE80211_HT_CAP_RX_STBC_SHIFT; 1154 mi->tx_flags |= stbc << IEEE80211_TX_CTL_STBC_SHIFT; 1155 1156 if (sta_cap & IEEE80211_HT_CAP_LDPC_CODING) 1157 mi->tx_flags |= IEEE80211_TX_CTL_LDPC; 1158 } 1159 1160 for (i = 0; i < ARRAY_SIZE(mi->groups); i++) { 1161 u32 gflags = minstrel_mcs_groups[i].flags; 1162 int bw, nss; 1163 1164 mi->groups[i].supported = 0; 1165 if (i == MINSTREL_CCK_GROUP) { 1166 minstrel_ht_update_cck(mp, mi, sband, sta); 1167 continue; 1168 } 1169 1170 if (gflags & IEEE80211_TX_RC_SHORT_GI) { 1171 if (gflags & IEEE80211_TX_RC_40_MHZ_WIDTH) { 1172 if (!(sta_cap & IEEE80211_HT_CAP_SGI_40)) 1173 continue; 1174 } else { 1175 if (!(sta_cap & IEEE80211_HT_CAP_SGI_20)) 1176 continue; 1177 } 1178 } 1179 1180 if (gflags & IEEE80211_TX_RC_40_MHZ_WIDTH && 1181 sta->bandwidth < IEEE80211_STA_RX_BW_40) 1182 continue; 1183 1184 nss = minstrel_mcs_groups[i].streams; 1185 1186 /* Mark MCS > 7 as unsupported if STA is in static SMPS mode */ 1187 if (sta->smps_mode == IEEE80211_SMPS_STATIC && nss > 1) 1188 continue; 1189 1190 /* HT rate */ 1191 if (gflags & IEEE80211_TX_RC_MCS) { 1192 #ifdef CONFIG_MAC80211_RC_MINSTREL_VHT 1193 if (use_vht && minstrel_vht_only) 1194 continue; 1195 #endif 1196 mi->groups[i].supported = mcs->rx_mask[nss - 1]; 1197 if (mi->groups[i].supported) 1198 n_supported++; 1199 continue; 1200 } 1201 1202 /* VHT rate */ 1203 if (!vht_cap->vht_supported || 1204 WARN_ON(!(gflags & IEEE80211_TX_RC_VHT_MCS)) || 1205 WARN_ON(gflags & IEEE80211_TX_RC_160_MHZ_WIDTH)) 1206 continue; 1207 1208 if (gflags & IEEE80211_TX_RC_80_MHZ_WIDTH) { 1209 if (sta->bandwidth < IEEE80211_STA_RX_BW_80 || 1210 ((gflags & IEEE80211_TX_RC_SHORT_GI) && 1211 !(vht_cap->cap & IEEE80211_VHT_CAP_SHORT_GI_80))) { 1212 continue; 1213 } 1214 } 1215 1216 if (gflags & IEEE80211_TX_RC_40_MHZ_WIDTH) 1217 bw = BW_40; 1218 else if (gflags & IEEE80211_TX_RC_80_MHZ_WIDTH) 1219 bw = BW_80; 1220 else 1221 bw = BW_20; 1222 1223 mi->groups[i].supported = minstrel_get_valid_vht_rates(bw, nss, 1224 vht_cap->vht_mcs.tx_mcs_map); 1225 1226 if (mi->groups[i].supported) 1227 n_supported++; 1228 } 1229 1230 if (!n_supported) 1231 goto use_legacy; 1232 1233 /* create an initial rate table with the lowest supported rates */ 1234 minstrel_ht_update_stats(mp, mi); 1235 minstrel_ht_update_rates(mp, mi); 1236 1237 return; 1238 1239 use_legacy: 1240 msp->is_ht = false; 1241 memset(&msp->legacy, 0, sizeof(msp->legacy)); 1242 msp->legacy.r = msp->ratelist; 1243 msp->legacy.sample_table = msp->sample_table; 1244 return mac80211_minstrel.rate_init(priv, sband, chandef, sta, 1245 &msp->legacy); 1246 } 1247 1248 static void 1249 minstrel_ht_rate_init(void *priv, struct ieee80211_supported_band *sband, 1250 struct cfg80211_chan_def *chandef, 1251 struct ieee80211_sta *sta, void *priv_sta) 1252 { 1253 minstrel_ht_update_caps(priv, sband, chandef, sta, priv_sta); 1254 } 1255 1256 static void 1257 minstrel_ht_rate_update(void *priv, struct ieee80211_supported_band *sband, 1258 struct cfg80211_chan_def *chandef, 1259 struct ieee80211_sta *sta, void *priv_sta, 1260 u32 changed) 1261 { 1262 minstrel_ht_update_caps(priv, sband, chandef, sta, priv_sta); 1263 } 1264 1265 static void * 1266 minstrel_ht_alloc_sta(void *priv, struct ieee80211_sta *sta, gfp_t gfp) 1267 { 1268 struct ieee80211_supported_band *sband; 1269 struct minstrel_ht_sta_priv *msp; 1270 struct minstrel_priv *mp = priv; 1271 struct ieee80211_hw *hw = mp->hw; 1272 int max_rates = 0; 1273 int i; 1274 1275 for (i = 0; i < IEEE80211_NUM_BANDS; i++) { 1276 sband = hw->wiphy->bands[i]; 1277 if (sband && sband->n_bitrates > max_rates) 1278 max_rates = sband->n_bitrates; 1279 } 1280 1281 msp = kzalloc(sizeof(*msp), gfp); 1282 if (!msp) 1283 return NULL; 1284 1285 msp->ratelist = kzalloc(sizeof(struct minstrel_rate) * max_rates, gfp); 1286 if (!msp->ratelist) 1287 goto error; 1288 1289 msp->sample_table = kmalloc(SAMPLE_COLUMNS * max_rates, gfp); 1290 if (!msp->sample_table) 1291 goto error1; 1292 1293 return msp; 1294 1295 error1: 1296 kfree(msp->ratelist); 1297 error: 1298 kfree(msp); 1299 return NULL; 1300 } 1301 1302 static void 1303 minstrel_ht_free_sta(void *priv, struct ieee80211_sta *sta, void *priv_sta) 1304 { 1305 struct minstrel_ht_sta_priv *msp = priv_sta; 1306 1307 kfree(msp->sample_table); 1308 kfree(msp->ratelist); 1309 kfree(msp); 1310 } 1311 1312 static void * 1313 minstrel_ht_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir) 1314 { 1315 return mac80211_minstrel.alloc(hw, debugfsdir); 1316 } 1317 1318 static void 1319 minstrel_ht_free(void *priv) 1320 { 1321 mac80211_minstrel.free(priv); 1322 } 1323 1324 static u32 minstrel_ht_get_expected_throughput(void *priv_sta) 1325 { 1326 struct minstrel_ht_sta_priv *msp = priv_sta; 1327 struct minstrel_ht_sta *mi = &msp->ht; 1328 int i, j, prob, tp_avg; 1329 1330 if (!msp->is_ht) 1331 return mac80211_minstrel.get_expected_throughput(priv_sta); 1332 1333 i = mi->max_tp_rate[0] / MCS_GROUP_RATES; 1334 j = mi->max_tp_rate[0] % MCS_GROUP_RATES; 1335 prob = mi->groups[i].rates[j].prob_ewma; 1336 1337 /* convert tp_avg from pkt per second in kbps */ 1338 tp_avg = minstrel_ht_get_tp_avg(mi, i, j, prob) * 10; 1339 tp_avg = tp_avg * AVG_PKT_SIZE * 8 / 1024; 1340 1341 return tp_avg; 1342 } 1343 1344 static const struct rate_control_ops mac80211_minstrel_ht = { 1345 .name = "minstrel_ht", 1346 .tx_status_noskb = minstrel_ht_tx_status, 1347 .get_rate = minstrel_ht_get_rate, 1348 .rate_init = minstrel_ht_rate_init, 1349 .rate_update = minstrel_ht_rate_update, 1350 .alloc_sta = minstrel_ht_alloc_sta, 1351 .free_sta = minstrel_ht_free_sta, 1352 .alloc = minstrel_ht_alloc, 1353 .free = minstrel_ht_free, 1354 #ifdef CONFIG_MAC80211_DEBUGFS 1355 .add_sta_debugfs = minstrel_ht_add_sta_debugfs, 1356 .remove_sta_debugfs = minstrel_ht_remove_sta_debugfs, 1357 #endif 1358 .get_expected_throughput = minstrel_ht_get_expected_throughput, 1359 }; 1360 1361 1362 static void __init init_sample_table(void) 1363 { 1364 int col, i, new_idx; 1365 u8 rnd[MCS_GROUP_RATES]; 1366 1367 memset(sample_table, 0xff, sizeof(sample_table)); 1368 for (col = 0; col < SAMPLE_COLUMNS; col++) { 1369 prandom_bytes(rnd, sizeof(rnd)); 1370 for (i = 0; i < MCS_GROUP_RATES; i++) { 1371 new_idx = (i + rnd[i]) % MCS_GROUP_RATES; 1372 while (sample_table[col][new_idx] != 0xff) 1373 new_idx = (new_idx + 1) % MCS_GROUP_RATES; 1374 1375 sample_table[col][new_idx] = i; 1376 } 1377 } 1378 } 1379 1380 int __init 1381 rc80211_minstrel_ht_init(void) 1382 { 1383 init_sample_table(); 1384 return ieee80211_rate_control_register(&mac80211_minstrel_ht); 1385 } 1386 1387 void 1388 rc80211_minstrel_ht_exit(void) 1389 { 1390 ieee80211_rate_control_unregister(&mac80211_minstrel_ht); 1391 } 1392