1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2010-2013 Felix Fietkau <nbd@openwrt.org> 4 * Copyright (C) 2019-2020 Intel Corporation 5 */ 6 #include <linux/netdevice.h> 7 #include <linux/types.h> 8 #include <linux/skbuff.h> 9 #include <linux/debugfs.h> 10 #include <linux/random.h> 11 #include <linux/moduleparam.h> 12 #include <linux/ieee80211.h> 13 #include <net/mac80211.h> 14 #include "rate.h" 15 #include "sta_info.h" 16 #include "rc80211_minstrel_ht.h" 17 18 #define AVG_AMPDU_SIZE 16 19 #define AVG_PKT_SIZE 1200 20 21 #define SAMPLE_SWITCH_THR 100 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 #define _MAX(a, b) (((a)>(b))?(a):(b)) 54 55 #define GROUP_SHIFT(duration) \ 56 _MAX(0, 16 - __builtin_clz(duration)) 57 58 /* MCS rate information for an MCS group */ 59 #define __MCS_GROUP(_streams, _sgi, _ht40, _s) \ 60 [GROUP_IDX(_streams, _sgi, _ht40)] = { \ 61 .streams = _streams, \ 62 .shift = _s, \ 63 .bw = _ht40, \ 64 .flags = \ 65 IEEE80211_TX_RC_MCS | \ 66 (_sgi ? IEEE80211_TX_RC_SHORT_GI : 0) | \ 67 (_ht40 ? IEEE80211_TX_RC_40_MHZ_WIDTH : 0), \ 68 .duration = { \ 69 MCS_DURATION(_streams, _sgi, _ht40 ? 54 : 26) >> _s, \ 70 MCS_DURATION(_streams, _sgi, _ht40 ? 108 : 52) >> _s, \ 71 MCS_DURATION(_streams, _sgi, _ht40 ? 162 : 78) >> _s, \ 72 MCS_DURATION(_streams, _sgi, _ht40 ? 216 : 104) >> _s, \ 73 MCS_DURATION(_streams, _sgi, _ht40 ? 324 : 156) >> _s, \ 74 MCS_DURATION(_streams, _sgi, _ht40 ? 432 : 208) >> _s, \ 75 MCS_DURATION(_streams, _sgi, _ht40 ? 486 : 234) >> _s, \ 76 MCS_DURATION(_streams, _sgi, _ht40 ? 540 : 260) >> _s \ 77 } \ 78 } 79 80 #define MCS_GROUP_SHIFT(_streams, _sgi, _ht40) \ 81 GROUP_SHIFT(MCS_DURATION(_streams, _sgi, _ht40 ? 54 : 26)) 82 83 #define MCS_GROUP(_streams, _sgi, _ht40) \ 84 __MCS_GROUP(_streams, _sgi, _ht40, \ 85 MCS_GROUP_SHIFT(_streams, _sgi, _ht40)) 86 87 #define VHT_GROUP_IDX(_streams, _sgi, _bw) \ 88 (MINSTREL_VHT_GROUP_0 + \ 89 MINSTREL_MAX_STREAMS * 2 * (_bw) + \ 90 MINSTREL_MAX_STREAMS * (_sgi) + \ 91 (_streams) - 1) 92 93 #define BW2VBPS(_bw, r3, r2, r1) \ 94 (_bw == BW_80 ? r3 : _bw == BW_40 ? r2 : r1) 95 96 #define __VHT_GROUP(_streams, _sgi, _bw, _s) \ 97 [VHT_GROUP_IDX(_streams, _sgi, _bw)] = { \ 98 .streams = _streams, \ 99 .shift = _s, \ 100 .bw = _bw, \ 101 .flags = \ 102 IEEE80211_TX_RC_VHT_MCS | \ 103 (_sgi ? IEEE80211_TX_RC_SHORT_GI : 0) | \ 104 (_bw == BW_80 ? IEEE80211_TX_RC_80_MHZ_WIDTH : \ 105 _bw == BW_40 ? IEEE80211_TX_RC_40_MHZ_WIDTH : 0), \ 106 .duration = { \ 107 MCS_DURATION(_streams, _sgi, \ 108 BW2VBPS(_bw, 117, 54, 26)) >> _s, \ 109 MCS_DURATION(_streams, _sgi, \ 110 BW2VBPS(_bw, 234, 108, 52)) >> _s, \ 111 MCS_DURATION(_streams, _sgi, \ 112 BW2VBPS(_bw, 351, 162, 78)) >> _s, \ 113 MCS_DURATION(_streams, _sgi, \ 114 BW2VBPS(_bw, 468, 216, 104)) >> _s, \ 115 MCS_DURATION(_streams, _sgi, \ 116 BW2VBPS(_bw, 702, 324, 156)) >> _s, \ 117 MCS_DURATION(_streams, _sgi, \ 118 BW2VBPS(_bw, 936, 432, 208)) >> _s, \ 119 MCS_DURATION(_streams, _sgi, \ 120 BW2VBPS(_bw, 1053, 486, 234)) >> _s, \ 121 MCS_DURATION(_streams, _sgi, \ 122 BW2VBPS(_bw, 1170, 540, 260)) >> _s, \ 123 MCS_DURATION(_streams, _sgi, \ 124 BW2VBPS(_bw, 1404, 648, 312)) >> _s, \ 125 MCS_DURATION(_streams, _sgi, \ 126 BW2VBPS(_bw, 1560, 720, 346)) >> _s \ 127 } \ 128 } 129 130 #define VHT_GROUP_SHIFT(_streams, _sgi, _bw) \ 131 GROUP_SHIFT(MCS_DURATION(_streams, _sgi, \ 132 BW2VBPS(_bw, 117, 54, 26))) 133 134 #define VHT_GROUP(_streams, _sgi, _bw) \ 135 __VHT_GROUP(_streams, _sgi, _bw, \ 136 VHT_GROUP_SHIFT(_streams, _sgi, _bw)) 137 138 #define CCK_DURATION(_bitrate, _short) \ 139 (1000 * (10 /* SIFS */ + \ 140 (_short ? 72 + 24 : 144 + 48) + \ 141 (8 * (AVG_PKT_SIZE + 4) * 10) / (_bitrate))) 142 143 #define CCK_DURATION_LIST(_short, _s) \ 144 CCK_DURATION(10, _short) >> _s, \ 145 CCK_DURATION(20, _short) >> _s, \ 146 CCK_DURATION(55, _short) >> _s, \ 147 CCK_DURATION(110, _short) >> _s 148 149 #define __CCK_GROUP(_s) \ 150 [MINSTREL_CCK_GROUP] = { \ 151 .streams = 1, \ 152 .flags = 0, \ 153 .shift = _s, \ 154 .duration = { \ 155 CCK_DURATION_LIST(false, _s), \ 156 CCK_DURATION_LIST(true, _s) \ 157 } \ 158 } 159 160 #define CCK_GROUP_SHIFT \ 161 GROUP_SHIFT(CCK_DURATION(10, false)) 162 163 #define CCK_GROUP __CCK_GROUP(CCK_GROUP_SHIFT) 164 165 #define OFDM_DURATION(_bitrate) \ 166 (1000 * (16 /* SIFS + signal ext */ + \ 167 16 /* T_PREAMBLE */ + \ 168 4 /* T_SIGNAL */ + \ 169 4 * (((16 + 80 * (AVG_PKT_SIZE + 4) + 6) / \ 170 ((_bitrate) * 4))))) 171 172 #define OFDM_DURATION_LIST(_s) \ 173 OFDM_DURATION(60) >> _s, \ 174 OFDM_DURATION(90) >> _s, \ 175 OFDM_DURATION(120) >> _s, \ 176 OFDM_DURATION(180) >> _s, \ 177 OFDM_DURATION(240) >> _s, \ 178 OFDM_DURATION(360) >> _s, \ 179 OFDM_DURATION(480) >> _s, \ 180 OFDM_DURATION(540) >> _s 181 182 #define __OFDM_GROUP(_s) \ 183 [MINSTREL_OFDM_GROUP] = { \ 184 .streams = 1, \ 185 .flags = 0, \ 186 .shift = _s, \ 187 .duration = { \ 188 OFDM_DURATION_LIST(_s), \ 189 } \ 190 } 191 192 #define OFDM_GROUP_SHIFT \ 193 GROUP_SHIFT(OFDM_DURATION(60)) 194 195 #define OFDM_GROUP __OFDM_GROUP(OFDM_GROUP_SHIFT) 196 197 198 static bool minstrel_vht_only = true; 199 module_param(minstrel_vht_only, bool, 0644); 200 MODULE_PARM_DESC(minstrel_vht_only, 201 "Use only VHT rates when VHT is supported by sta."); 202 203 /* 204 * To enable sufficiently targeted rate sampling, MCS rates are divided into 205 * groups, based on the number of streams and flags (HT40, SGI) that they 206 * use. 207 * 208 * Sortorder has to be fixed for GROUP_IDX macro to be applicable: 209 * BW -> SGI -> #streams 210 */ 211 const struct mcs_group minstrel_mcs_groups[] = { 212 MCS_GROUP(1, 0, BW_20), 213 MCS_GROUP(2, 0, BW_20), 214 MCS_GROUP(3, 0, BW_20), 215 MCS_GROUP(4, 0, BW_20), 216 217 MCS_GROUP(1, 1, BW_20), 218 MCS_GROUP(2, 1, BW_20), 219 MCS_GROUP(3, 1, BW_20), 220 MCS_GROUP(4, 1, BW_20), 221 222 MCS_GROUP(1, 0, BW_40), 223 MCS_GROUP(2, 0, BW_40), 224 MCS_GROUP(3, 0, BW_40), 225 MCS_GROUP(4, 0, BW_40), 226 227 MCS_GROUP(1, 1, BW_40), 228 MCS_GROUP(2, 1, BW_40), 229 MCS_GROUP(3, 1, BW_40), 230 MCS_GROUP(4, 1, BW_40), 231 232 CCK_GROUP, 233 OFDM_GROUP, 234 235 VHT_GROUP(1, 0, BW_20), 236 VHT_GROUP(2, 0, BW_20), 237 VHT_GROUP(3, 0, BW_20), 238 VHT_GROUP(4, 0, BW_20), 239 240 VHT_GROUP(1, 1, BW_20), 241 VHT_GROUP(2, 1, BW_20), 242 VHT_GROUP(3, 1, BW_20), 243 VHT_GROUP(4, 1, BW_20), 244 245 VHT_GROUP(1, 0, BW_40), 246 VHT_GROUP(2, 0, BW_40), 247 VHT_GROUP(3, 0, BW_40), 248 VHT_GROUP(4, 0, BW_40), 249 250 VHT_GROUP(1, 1, BW_40), 251 VHT_GROUP(2, 1, BW_40), 252 VHT_GROUP(3, 1, BW_40), 253 VHT_GROUP(4, 1, BW_40), 254 255 VHT_GROUP(1, 0, BW_80), 256 VHT_GROUP(2, 0, BW_80), 257 VHT_GROUP(3, 0, BW_80), 258 VHT_GROUP(4, 0, BW_80), 259 260 VHT_GROUP(1, 1, BW_80), 261 VHT_GROUP(2, 1, BW_80), 262 VHT_GROUP(3, 1, BW_80), 263 VHT_GROUP(4, 1, BW_80), 264 }; 265 266 const s16 minstrel_cck_bitrates[4] = { 10, 20, 55, 110 }; 267 const s16 minstrel_ofdm_bitrates[8] = { 60, 90, 120, 180, 240, 360, 480, 540 }; 268 static u8 sample_table[SAMPLE_COLUMNS][MCS_GROUP_RATES] __read_mostly; 269 static const u8 minstrel_sample_seq[] = { 270 MINSTREL_SAMPLE_TYPE_INC, 271 MINSTREL_SAMPLE_TYPE_JUMP, 272 MINSTREL_SAMPLE_TYPE_INC, 273 MINSTREL_SAMPLE_TYPE_JUMP, 274 MINSTREL_SAMPLE_TYPE_INC, 275 MINSTREL_SAMPLE_TYPE_SLOW, 276 }; 277 278 static void 279 minstrel_ht_update_rates(struct minstrel_priv *mp, struct minstrel_ht_sta *mi); 280 281 /* 282 * Some VHT MCSes are invalid (when Ndbps / Nes is not an integer) 283 * e.g for MCS9@20MHzx1Nss: Ndbps=8x52*(5/6) Nes=1 284 * 285 * Returns the valid mcs map for struct minstrel_mcs_group_data.supported 286 */ 287 static u16 288 minstrel_get_valid_vht_rates(int bw, int nss, __le16 mcs_map) 289 { 290 u16 mask = 0; 291 292 if (bw == BW_20) { 293 if (nss != 3 && nss != 6) 294 mask = BIT(9); 295 } else if (bw == BW_80) { 296 if (nss == 3 || nss == 7) 297 mask = BIT(6); 298 else if (nss == 6) 299 mask = BIT(9); 300 } else { 301 WARN_ON(bw != BW_40); 302 } 303 304 switch ((le16_to_cpu(mcs_map) >> (2 * (nss - 1))) & 3) { 305 case IEEE80211_VHT_MCS_SUPPORT_0_7: 306 mask |= 0x300; 307 break; 308 case IEEE80211_VHT_MCS_SUPPORT_0_8: 309 mask |= 0x200; 310 break; 311 case IEEE80211_VHT_MCS_SUPPORT_0_9: 312 break; 313 default: 314 mask = 0x3ff; 315 } 316 317 return 0x3ff & ~mask; 318 } 319 320 static bool 321 minstrel_ht_is_legacy_group(int group) 322 { 323 return group == MINSTREL_CCK_GROUP || 324 group == MINSTREL_OFDM_GROUP; 325 } 326 327 /* 328 * Look up an MCS group index based on mac80211 rate information 329 */ 330 static int 331 minstrel_ht_get_group_idx(struct ieee80211_tx_rate *rate) 332 { 333 return GROUP_IDX((rate->idx / 8) + 1, 334 !!(rate->flags & IEEE80211_TX_RC_SHORT_GI), 335 !!(rate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH)); 336 } 337 338 static int 339 minstrel_vht_get_group_idx(struct ieee80211_tx_rate *rate) 340 { 341 return VHT_GROUP_IDX(ieee80211_rate_get_vht_nss(rate), 342 !!(rate->flags & IEEE80211_TX_RC_SHORT_GI), 343 !!(rate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH) + 344 2*!!(rate->flags & IEEE80211_TX_RC_80_MHZ_WIDTH)); 345 } 346 347 static struct minstrel_rate_stats * 348 minstrel_ht_get_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi, 349 struct ieee80211_tx_rate *rate) 350 { 351 int group, idx; 352 353 if (rate->flags & IEEE80211_TX_RC_MCS) { 354 group = minstrel_ht_get_group_idx(rate); 355 idx = rate->idx % 8; 356 goto out; 357 } 358 359 if (rate->flags & IEEE80211_TX_RC_VHT_MCS) { 360 group = minstrel_vht_get_group_idx(rate); 361 idx = ieee80211_rate_get_vht_mcs(rate); 362 goto out; 363 } 364 365 group = MINSTREL_CCK_GROUP; 366 for (idx = 0; idx < ARRAY_SIZE(mp->cck_rates); idx++) { 367 if (rate->idx != mp->cck_rates[idx]) 368 continue; 369 370 /* short preamble */ 371 if ((mi->supported[group] & BIT(idx + 4)) && 372 (rate->flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE)) 373 idx += 4; 374 goto out; 375 } 376 377 group = MINSTREL_OFDM_GROUP; 378 for (idx = 0; idx < ARRAY_SIZE(mp->ofdm_rates[0]); idx++) 379 if (rate->idx == mp->ofdm_rates[mi->band][idx]) 380 goto out; 381 382 idx = 0; 383 out: 384 return &mi->groups[group].rates[idx]; 385 } 386 387 static inline struct minstrel_rate_stats * 388 minstrel_get_ratestats(struct minstrel_ht_sta *mi, int index) 389 { 390 return &mi->groups[MI_RATE_GROUP(index)].rates[MI_RATE_IDX(index)]; 391 } 392 393 static inline int minstrel_get_duration(int index) 394 { 395 const struct mcs_group *group = &minstrel_mcs_groups[MI_RATE_GROUP(index)]; 396 unsigned int duration = group->duration[MI_RATE_IDX(index)]; 397 398 return duration << group->shift; 399 } 400 401 static unsigned int 402 minstrel_ht_avg_ampdu_len(struct minstrel_ht_sta *mi) 403 { 404 int duration; 405 406 if (mi->avg_ampdu_len) 407 return MINSTREL_TRUNC(mi->avg_ampdu_len); 408 409 if (minstrel_ht_is_legacy_group(MI_RATE_GROUP(mi->max_tp_rate[0]))) 410 return 1; 411 412 duration = minstrel_get_duration(mi->max_tp_rate[0]); 413 414 if (duration > 400 * 1000) 415 return 2; 416 417 if (duration > 250 * 1000) 418 return 4; 419 420 if (duration > 150 * 1000) 421 return 8; 422 423 return 16; 424 } 425 426 /* 427 * Return current throughput based on the average A-MPDU length, taking into 428 * account the expected number of retransmissions and their expected length 429 */ 430 int 431 minstrel_ht_get_tp_avg(struct minstrel_ht_sta *mi, int group, int rate, 432 int prob_avg) 433 { 434 unsigned int nsecs = 0, overhead = mi->overhead; 435 unsigned int ampdu_len = 1; 436 437 /* do not account throughput if sucess prob is below 10% */ 438 if (prob_avg < MINSTREL_FRAC(10, 100)) 439 return 0; 440 441 if (minstrel_ht_is_legacy_group(group)) 442 overhead = mi->overhead_legacy; 443 else 444 ampdu_len = minstrel_ht_avg_ampdu_len(mi); 445 446 nsecs = 1000 * overhead / ampdu_len; 447 nsecs += minstrel_mcs_groups[group].duration[rate] << 448 minstrel_mcs_groups[group].shift; 449 450 /* 451 * For the throughput calculation, limit the probability value to 90% to 452 * account for collision related packet error rate fluctuation 453 * (prob is scaled - see MINSTREL_FRAC above) 454 */ 455 if (prob_avg > MINSTREL_FRAC(90, 100)) 456 prob_avg = MINSTREL_FRAC(90, 100); 457 458 return MINSTREL_TRUNC(100 * ((prob_avg * 1000000) / nsecs)); 459 } 460 461 /* 462 * Find & sort topmost throughput rates 463 * 464 * If multiple rates provide equal throughput the sorting is based on their 465 * current success probability. Higher success probability is preferred among 466 * MCS groups, CCK rates do not provide aggregation and are therefore at last. 467 */ 468 static void 469 minstrel_ht_sort_best_tp_rates(struct minstrel_ht_sta *mi, u16 index, 470 u16 *tp_list) 471 { 472 int cur_group, cur_idx, cur_tp_avg, cur_prob; 473 int tmp_group, tmp_idx, tmp_tp_avg, tmp_prob; 474 int j = MAX_THR_RATES; 475 476 cur_group = MI_RATE_GROUP(index); 477 cur_idx = MI_RATE_IDX(index); 478 cur_prob = mi->groups[cur_group].rates[cur_idx].prob_avg; 479 cur_tp_avg = minstrel_ht_get_tp_avg(mi, cur_group, cur_idx, cur_prob); 480 481 do { 482 tmp_group = MI_RATE_GROUP(tp_list[j - 1]); 483 tmp_idx = MI_RATE_IDX(tp_list[j - 1]); 484 tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_avg; 485 tmp_tp_avg = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx, 486 tmp_prob); 487 if (cur_tp_avg < tmp_tp_avg || 488 (cur_tp_avg == tmp_tp_avg && cur_prob <= tmp_prob)) 489 break; 490 j--; 491 } while (j > 0); 492 493 if (j < MAX_THR_RATES - 1) { 494 memmove(&tp_list[j + 1], &tp_list[j], (sizeof(*tp_list) * 495 (MAX_THR_RATES - (j + 1)))); 496 } 497 if (j < MAX_THR_RATES) 498 tp_list[j] = index; 499 } 500 501 /* 502 * Find and set the topmost probability rate per sta and per group 503 */ 504 static void 505 minstrel_ht_set_best_prob_rate(struct minstrel_ht_sta *mi, u16 *dest, u16 index) 506 { 507 struct minstrel_mcs_group_data *mg; 508 struct minstrel_rate_stats *mrs; 509 int tmp_group, tmp_idx, tmp_tp_avg, tmp_prob; 510 int max_tp_group, max_tp_idx, max_tp_prob; 511 int cur_tp_avg, cur_group, cur_idx; 512 int max_gpr_group, max_gpr_idx; 513 int max_gpr_tp_avg, max_gpr_prob; 514 515 cur_group = MI_RATE_GROUP(index); 516 cur_idx = MI_RATE_IDX(index); 517 mg = &mi->groups[cur_group]; 518 mrs = &mg->rates[cur_idx]; 519 520 tmp_group = MI_RATE_GROUP(*dest); 521 tmp_idx = MI_RATE_IDX(*dest); 522 tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_avg; 523 tmp_tp_avg = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx, tmp_prob); 524 525 /* if max_tp_rate[0] is from MCS_GROUP max_prob_rate get selected from 526 * MCS_GROUP as well as CCK_GROUP rates do not allow aggregation */ 527 max_tp_group = MI_RATE_GROUP(mi->max_tp_rate[0]); 528 max_tp_idx = MI_RATE_IDX(mi->max_tp_rate[0]); 529 max_tp_prob = mi->groups[max_tp_group].rates[max_tp_idx].prob_avg; 530 531 if (minstrel_ht_is_legacy_group(MI_RATE_GROUP(index)) && 532 !minstrel_ht_is_legacy_group(max_tp_group)) 533 return; 534 535 /* skip rates faster than max tp rate with lower prob */ 536 if (minstrel_get_duration(mi->max_tp_rate[0]) > minstrel_get_duration(index) && 537 mrs->prob_avg < max_tp_prob) 538 return; 539 540 max_gpr_group = MI_RATE_GROUP(mg->max_group_prob_rate); 541 max_gpr_idx = MI_RATE_IDX(mg->max_group_prob_rate); 542 max_gpr_prob = mi->groups[max_gpr_group].rates[max_gpr_idx].prob_avg; 543 544 if (mrs->prob_avg > MINSTREL_FRAC(75, 100)) { 545 cur_tp_avg = minstrel_ht_get_tp_avg(mi, cur_group, cur_idx, 546 mrs->prob_avg); 547 if (cur_tp_avg > tmp_tp_avg) 548 *dest = index; 549 550 max_gpr_tp_avg = minstrel_ht_get_tp_avg(mi, max_gpr_group, 551 max_gpr_idx, 552 max_gpr_prob); 553 if (cur_tp_avg > max_gpr_tp_avg) 554 mg->max_group_prob_rate = index; 555 } else { 556 if (mrs->prob_avg > tmp_prob) 557 *dest = index; 558 if (mrs->prob_avg > max_gpr_prob) 559 mg->max_group_prob_rate = index; 560 } 561 } 562 563 564 /* 565 * Assign new rate set per sta and use CCK rates only if the fastest 566 * rate (max_tp_rate[0]) is from CCK group. This prohibits such sorted 567 * rate sets where MCS and CCK rates are mixed, because CCK rates can 568 * not use aggregation. 569 */ 570 static void 571 minstrel_ht_assign_best_tp_rates(struct minstrel_ht_sta *mi, 572 u16 tmp_mcs_tp_rate[MAX_THR_RATES], 573 u16 tmp_legacy_tp_rate[MAX_THR_RATES]) 574 { 575 unsigned int tmp_group, tmp_idx, tmp_cck_tp, tmp_mcs_tp, tmp_prob; 576 int i; 577 578 tmp_group = MI_RATE_GROUP(tmp_legacy_tp_rate[0]); 579 tmp_idx = MI_RATE_IDX(tmp_legacy_tp_rate[0]); 580 tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_avg; 581 tmp_cck_tp = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx, tmp_prob); 582 583 tmp_group = MI_RATE_GROUP(tmp_mcs_tp_rate[0]); 584 tmp_idx = MI_RATE_IDX(tmp_mcs_tp_rate[0]); 585 tmp_prob = mi->groups[tmp_group].rates[tmp_idx].prob_avg; 586 tmp_mcs_tp = minstrel_ht_get_tp_avg(mi, tmp_group, tmp_idx, tmp_prob); 587 588 if (tmp_cck_tp > tmp_mcs_tp) { 589 for(i = 0; i < MAX_THR_RATES; i++) { 590 minstrel_ht_sort_best_tp_rates(mi, tmp_legacy_tp_rate[i], 591 tmp_mcs_tp_rate); 592 } 593 } 594 595 } 596 597 /* 598 * Try to increase robustness of max_prob rate by decrease number of 599 * streams if possible. 600 */ 601 static inline void 602 minstrel_ht_prob_rate_reduce_streams(struct minstrel_ht_sta *mi) 603 { 604 struct minstrel_mcs_group_data *mg; 605 int tmp_max_streams, group, tmp_idx, tmp_prob; 606 int tmp_tp = 0; 607 608 if (!mi->sta->ht_cap.ht_supported) 609 return; 610 611 group = MI_RATE_GROUP(mi->max_tp_rate[0]); 612 tmp_max_streams = minstrel_mcs_groups[group].streams; 613 for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) { 614 mg = &mi->groups[group]; 615 if (!mi->supported[group] || group == MINSTREL_CCK_GROUP) 616 continue; 617 618 tmp_idx = MI_RATE_IDX(mg->max_group_prob_rate); 619 tmp_prob = mi->groups[group].rates[tmp_idx].prob_avg; 620 621 if (tmp_tp < minstrel_ht_get_tp_avg(mi, group, tmp_idx, tmp_prob) && 622 (minstrel_mcs_groups[group].streams < tmp_max_streams)) { 623 mi->max_prob_rate = mg->max_group_prob_rate; 624 tmp_tp = minstrel_ht_get_tp_avg(mi, group, 625 tmp_idx, 626 tmp_prob); 627 } 628 } 629 } 630 631 static u16 632 __minstrel_ht_get_sample_rate(struct minstrel_ht_sta *mi, 633 enum minstrel_sample_type type) 634 { 635 u16 *rates = mi->sample[type].sample_rates; 636 u16 cur; 637 int i; 638 639 for (i = 0; i < MINSTREL_SAMPLE_RATES; i++) { 640 if (!rates[i]) 641 continue; 642 643 cur = rates[i]; 644 rates[i] = 0; 645 return cur; 646 } 647 648 return 0; 649 } 650 651 static inline int 652 minstrel_ewma(int old, int new, int weight) 653 { 654 int diff, incr; 655 656 diff = new - old; 657 incr = (EWMA_DIV - weight) * diff / EWMA_DIV; 658 659 return old + incr; 660 } 661 662 static inline int minstrel_filter_avg_add(u16 *prev_1, u16 *prev_2, s32 in) 663 { 664 s32 out_1 = *prev_1; 665 s32 out_2 = *prev_2; 666 s32 val; 667 668 if (!in) 669 in += 1; 670 671 if (!out_1) { 672 val = out_1 = in; 673 goto out; 674 } 675 676 val = MINSTREL_AVG_COEFF1 * in; 677 val += MINSTREL_AVG_COEFF2 * out_1; 678 val += MINSTREL_AVG_COEFF3 * out_2; 679 val >>= MINSTREL_SCALE; 680 681 if (val > 1 << MINSTREL_SCALE) 682 val = 1 << MINSTREL_SCALE; 683 if (val < 0) 684 val = 1; 685 686 out: 687 *prev_2 = out_1; 688 *prev_1 = val; 689 690 return val; 691 } 692 693 /* 694 * Recalculate statistics and counters of a given rate 695 */ 696 static void 697 minstrel_ht_calc_rate_stats(struct minstrel_priv *mp, 698 struct minstrel_rate_stats *mrs) 699 { 700 unsigned int cur_prob; 701 702 if (unlikely(mrs->attempts > 0)) { 703 cur_prob = MINSTREL_FRAC(mrs->success, mrs->attempts); 704 minstrel_filter_avg_add(&mrs->prob_avg, 705 &mrs->prob_avg_1, cur_prob); 706 mrs->att_hist += mrs->attempts; 707 mrs->succ_hist += mrs->success; 708 } 709 710 mrs->last_success = mrs->success; 711 mrs->last_attempts = mrs->attempts; 712 mrs->success = 0; 713 mrs->attempts = 0; 714 } 715 716 static bool 717 minstrel_ht_find_sample_rate(struct minstrel_ht_sta *mi, int type, int idx) 718 { 719 int i; 720 721 for (i = 0; i < MINSTREL_SAMPLE_RATES; i++) { 722 u16 cur = mi->sample[type].sample_rates[i]; 723 724 if (cur == idx) 725 return true; 726 727 if (!cur) 728 break; 729 } 730 731 return false; 732 } 733 734 static int 735 minstrel_ht_move_sample_rates(struct minstrel_ht_sta *mi, int type, 736 u32 fast_rate_dur, u32 slow_rate_dur) 737 { 738 u16 *rates = mi->sample[type].sample_rates; 739 int i, j; 740 741 for (i = 0, j = 0; i < MINSTREL_SAMPLE_RATES; i++) { 742 u32 duration; 743 bool valid = false; 744 u16 cur; 745 746 cur = rates[i]; 747 if (!cur) 748 continue; 749 750 duration = minstrel_get_duration(cur); 751 switch (type) { 752 case MINSTREL_SAMPLE_TYPE_SLOW: 753 valid = duration > fast_rate_dur && 754 duration < slow_rate_dur; 755 break; 756 case MINSTREL_SAMPLE_TYPE_INC: 757 case MINSTREL_SAMPLE_TYPE_JUMP: 758 valid = duration < fast_rate_dur; 759 break; 760 default: 761 valid = false; 762 break; 763 } 764 765 if (!valid) { 766 rates[i] = 0; 767 continue; 768 } 769 770 if (i == j) 771 continue; 772 773 rates[j++] = cur; 774 rates[i] = 0; 775 } 776 777 return j; 778 } 779 780 static int 781 minstrel_ht_group_min_rate_offset(struct minstrel_ht_sta *mi, int group, 782 u32 max_duration) 783 { 784 u16 supported = mi->supported[group]; 785 int i; 786 787 for (i = 0; i < MCS_GROUP_RATES && supported; i++, supported >>= 1) { 788 if (!(supported & BIT(0))) 789 continue; 790 791 if (minstrel_get_duration(MI_RATE(group, i)) >= max_duration) 792 continue; 793 794 return i; 795 } 796 797 return -1; 798 } 799 800 /* 801 * Incremental update rates: 802 * Flip through groups and pick the first group rate that is faster than the 803 * highest currently selected rate 804 */ 805 static u16 806 minstrel_ht_next_inc_rate(struct minstrel_ht_sta *mi, u32 fast_rate_dur) 807 { 808 u8 type = MINSTREL_SAMPLE_TYPE_INC; 809 int i, index = 0; 810 u8 group; 811 812 group = mi->sample[type].sample_group; 813 for (i = 0; i < ARRAY_SIZE(minstrel_mcs_groups); i++) { 814 group = (group + 1) % ARRAY_SIZE(minstrel_mcs_groups); 815 816 index = minstrel_ht_group_min_rate_offset(mi, group, 817 fast_rate_dur); 818 if (index < 0) 819 continue; 820 821 index = MI_RATE(group, index & 0xf); 822 if (!minstrel_ht_find_sample_rate(mi, type, index)) 823 goto out; 824 } 825 index = 0; 826 827 out: 828 mi->sample[type].sample_group = group; 829 830 return index; 831 } 832 833 static int 834 minstrel_ht_next_group_sample_rate(struct minstrel_ht_sta *mi, int group, 835 u16 supported, int offset) 836 { 837 struct minstrel_mcs_group_data *mg = &mi->groups[group]; 838 u16 idx; 839 int i; 840 841 for (i = 0; i < MCS_GROUP_RATES; i++) { 842 idx = sample_table[mg->column][mg->index]; 843 if (++mg->index >= MCS_GROUP_RATES) { 844 mg->index = 0; 845 if (++mg->column >= ARRAY_SIZE(sample_table)) 846 mg->column = 0; 847 } 848 849 if (idx < offset) 850 continue; 851 852 if (!(supported & BIT(idx))) 853 continue; 854 855 return MI_RATE(group, idx); 856 } 857 858 return -1; 859 } 860 861 /* 862 * Jump rates: 863 * Sample random rates, use those that are faster than the highest 864 * currently selected rate. Rates between the fastest and the slowest 865 * get sorted into the slow sample bucket, but only if it has room 866 */ 867 static u16 868 minstrel_ht_next_jump_rate(struct minstrel_ht_sta *mi, u32 fast_rate_dur, 869 u32 slow_rate_dur, int *slow_rate_ofs) 870 { 871 struct minstrel_rate_stats *mrs; 872 u32 max_duration = slow_rate_dur; 873 int i, index, offset; 874 u16 *slow_rates; 875 u16 supported; 876 u32 duration; 877 u8 group; 878 879 if (*slow_rate_ofs >= MINSTREL_SAMPLE_RATES) 880 max_duration = fast_rate_dur; 881 882 slow_rates = mi->sample[MINSTREL_SAMPLE_TYPE_SLOW].sample_rates; 883 group = mi->sample[MINSTREL_SAMPLE_TYPE_JUMP].sample_group; 884 for (i = 0; i < ARRAY_SIZE(minstrel_mcs_groups); i++) { 885 u8 type; 886 887 group = (group + 1) % ARRAY_SIZE(minstrel_mcs_groups); 888 889 supported = mi->supported[group]; 890 if (!supported) 891 continue; 892 893 offset = minstrel_ht_group_min_rate_offset(mi, group, 894 max_duration); 895 if (offset < 0) 896 continue; 897 898 index = minstrel_ht_next_group_sample_rate(mi, group, supported, 899 offset); 900 if (index < 0) 901 continue; 902 903 duration = minstrel_get_duration(index); 904 if (duration < fast_rate_dur) 905 type = MINSTREL_SAMPLE_TYPE_JUMP; 906 else 907 type = MINSTREL_SAMPLE_TYPE_SLOW; 908 909 if (minstrel_ht_find_sample_rate(mi, type, index)) 910 continue; 911 912 if (type == MINSTREL_SAMPLE_TYPE_JUMP) 913 goto found; 914 915 if (*slow_rate_ofs >= MINSTREL_SAMPLE_RATES) 916 continue; 917 918 if (duration >= slow_rate_dur) 919 continue; 920 921 /* skip slow rates with high success probability */ 922 mrs = minstrel_get_ratestats(mi, index); 923 if (mrs->prob_avg > MINSTREL_FRAC(95, 100)) 924 continue; 925 926 slow_rates[(*slow_rate_ofs)++] = index; 927 if (*slow_rate_ofs >= MINSTREL_SAMPLE_RATES) 928 max_duration = fast_rate_dur; 929 } 930 index = 0; 931 932 found: 933 mi->sample[MINSTREL_SAMPLE_TYPE_JUMP].sample_group = group; 934 935 return index; 936 } 937 938 static void 939 minstrel_ht_refill_sample_rates(struct minstrel_ht_sta *mi) 940 { 941 u32 prob_dur = minstrel_get_duration(mi->max_prob_rate); 942 u32 tp_dur = minstrel_get_duration(mi->max_tp_rate[0]); 943 u32 tp2_dur = minstrel_get_duration(mi->max_tp_rate[1]); 944 u32 fast_rate_dur = min(min(tp_dur, tp2_dur), prob_dur); 945 u32 slow_rate_dur = max(max(tp_dur, tp2_dur), prob_dur); 946 u16 *rates; 947 int i, j; 948 949 rates = mi->sample[MINSTREL_SAMPLE_TYPE_INC].sample_rates; 950 i = minstrel_ht_move_sample_rates(mi, MINSTREL_SAMPLE_TYPE_INC, 951 fast_rate_dur, slow_rate_dur); 952 while (i < MINSTREL_SAMPLE_RATES) { 953 rates[i] = minstrel_ht_next_inc_rate(mi, tp_dur); 954 if (!rates[i]) 955 break; 956 957 i++; 958 } 959 960 rates = mi->sample[MINSTREL_SAMPLE_TYPE_JUMP].sample_rates; 961 i = minstrel_ht_move_sample_rates(mi, MINSTREL_SAMPLE_TYPE_JUMP, 962 fast_rate_dur, slow_rate_dur); 963 j = minstrel_ht_move_sample_rates(mi, MINSTREL_SAMPLE_TYPE_SLOW, 964 fast_rate_dur, slow_rate_dur); 965 while (i < MINSTREL_SAMPLE_RATES) { 966 rates[i] = minstrel_ht_next_jump_rate(mi, fast_rate_dur, 967 slow_rate_dur, &j); 968 if (!rates[i]) 969 break; 970 971 i++; 972 } 973 974 for (i = 0; i < ARRAY_SIZE(mi->sample); i++) 975 memcpy(mi->sample[i].cur_sample_rates, mi->sample[i].sample_rates, 976 sizeof(mi->sample[i].cur_sample_rates)); 977 } 978 979 980 /* 981 * Update rate statistics and select new primary rates 982 * 983 * Rules for rate selection: 984 * - max_prob_rate must use only one stream, as a tradeoff between delivery 985 * probability and throughput during strong fluctuations 986 * - as long as the max prob rate has a probability of more than 75%, pick 987 * higher throughput rates, even if the probablity is a bit lower 988 */ 989 static void 990 minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi) 991 { 992 struct minstrel_mcs_group_data *mg; 993 struct minstrel_rate_stats *mrs; 994 int group, i, j, cur_prob; 995 u16 tmp_mcs_tp_rate[MAX_THR_RATES], tmp_group_tp_rate[MAX_THR_RATES]; 996 u16 tmp_legacy_tp_rate[MAX_THR_RATES], tmp_max_prob_rate; 997 u16 index; 998 bool ht_supported = mi->sta->ht_cap.ht_supported; 999 1000 if (mi->ampdu_packets > 0) { 1001 if (!ieee80211_hw_check(mp->hw, TX_STATUS_NO_AMPDU_LEN)) 1002 mi->avg_ampdu_len = minstrel_ewma(mi->avg_ampdu_len, 1003 MINSTREL_FRAC(mi->ampdu_len, mi->ampdu_packets), 1004 EWMA_LEVEL); 1005 else 1006 mi->avg_ampdu_len = 0; 1007 mi->ampdu_len = 0; 1008 mi->ampdu_packets = 0; 1009 } 1010 1011 if (mi->supported[MINSTREL_CCK_GROUP]) 1012 group = MINSTREL_CCK_GROUP; 1013 else if (mi->supported[MINSTREL_OFDM_GROUP]) 1014 group = MINSTREL_OFDM_GROUP; 1015 else 1016 group = 0; 1017 1018 index = MI_RATE(group, 0); 1019 for (j = 0; j < ARRAY_SIZE(tmp_legacy_tp_rate); j++) 1020 tmp_legacy_tp_rate[j] = index; 1021 1022 if (mi->supported[MINSTREL_VHT_GROUP_0]) 1023 group = MINSTREL_VHT_GROUP_0; 1024 else if (ht_supported) 1025 group = MINSTREL_HT_GROUP_0; 1026 else if (mi->supported[MINSTREL_CCK_GROUP]) 1027 group = MINSTREL_CCK_GROUP; 1028 else 1029 group = MINSTREL_OFDM_GROUP; 1030 1031 index = MI_RATE(group, 0); 1032 tmp_max_prob_rate = index; 1033 for (j = 0; j < ARRAY_SIZE(tmp_mcs_tp_rate); j++) 1034 tmp_mcs_tp_rate[j] = index; 1035 1036 /* Find best rate sets within all MCS groups*/ 1037 for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) { 1038 u16 *tp_rate = tmp_mcs_tp_rate; 1039 u16 last_prob = 0; 1040 1041 mg = &mi->groups[group]; 1042 if (!mi->supported[group]) 1043 continue; 1044 1045 /* (re)Initialize group rate indexes */ 1046 for(j = 0; j < MAX_THR_RATES; j++) 1047 tmp_group_tp_rate[j] = MI_RATE(group, 0); 1048 1049 if (group == MINSTREL_CCK_GROUP && ht_supported) 1050 tp_rate = tmp_legacy_tp_rate; 1051 1052 for (i = MCS_GROUP_RATES - 1; i >= 0; i--) { 1053 if (!(mi->supported[group] & BIT(i))) 1054 continue; 1055 1056 index = MI_RATE(group, i); 1057 1058 mrs = &mg->rates[i]; 1059 mrs->retry_updated = false; 1060 minstrel_ht_calc_rate_stats(mp, mrs); 1061 1062 if (mrs->att_hist) 1063 last_prob = max(last_prob, mrs->prob_avg); 1064 else 1065 mrs->prob_avg = max(last_prob, mrs->prob_avg); 1066 cur_prob = mrs->prob_avg; 1067 1068 if (minstrel_ht_get_tp_avg(mi, group, i, cur_prob) == 0) 1069 continue; 1070 1071 /* Find max throughput rate set */ 1072 minstrel_ht_sort_best_tp_rates(mi, index, tp_rate); 1073 1074 /* Find max throughput rate set within a group */ 1075 minstrel_ht_sort_best_tp_rates(mi, index, 1076 tmp_group_tp_rate); 1077 } 1078 1079 memcpy(mg->max_group_tp_rate, tmp_group_tp_rate, 1080 sizeof(mg->max_group_tp_rate)); 1081 } 1082 1083 /* Assign new rate set per sta */ 1084 minstrel_ht_assign_best_tp_rates(mi, tmp_mcs_tp_rate, 1085 tmp_legacy_tp_rate); 1086 memcpy(mi->max_tp_rate, tmp_mcs_tp_rate, sizeof(mi->max_tp_rate)); 1087 1088 for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) { 1089 if (!mi->supported[group]) 1090 continue; 1091 1092 mg = &mi->groups[group]; 1093 mg->max_group_prob_rate = MI_RATE(group, 0); 1094 1095 for (i = 0; i < MCS_GROUP_RATES; i++) { 1096 if (!(mi->supported[group] & BIT(i))) 1097 continue; 1098 1099 index = MI_RATE(group, i); 1100 1101 /* Find max probability rate per group and global */ 1102 minstrel_ht_set_best_prob_rate(mi, &tmp_max_prob_rate, 1103 index); 1104 } 1105 } 1106 1107 mi->max_prob_rate = tmp_max_prob_rate; 1108 1109 /* Try to increase robustness of max_prob_rate*/ 1110 minstrel_ht_prob_rate_reduce_streams(mi); 1111 minstrel_ht_refill_sample_rates(mi); 1112 1113 #ifdef CONFIG_MAC80211_DEBUGFS 1114 /* use fixed index if set */ 1115 if (mp->fixed_rate_idx != -1) { 1116 for (i = 0; i < 4; i++) 1117 mi->max_tp_rate[i] = mp->fixed_rate_idx; 1118 mi->max_prob_rate = mp->fixed_rate_idx; 1119 } 1120 #endif 1121 1122 /* Reset update timer */ 1123 mi->last_stats_update = jiffies; 1124 mi->sample_time = jiffies; 1125 } 1126 1127 static bool 1128 minstrel_ht_txstat_valid(struct minstrel_priv *mp, struct minstrel_ht_sta *mi, 1129 struct ieee80211_tx_rate *rate) 1130 { 1131 int i; 1132 1133 if (rate->idx < 0) 1134 return false; 1135 1136 if (!rate->count) 1137 return false; 1138 1139 if (rate->flags & IEEE80211_TX_RC_MCS || 1140 rate->flags & IEEE80211_TX_RC_VHT_MCS) 1141 return true; 1142 1143 for (i = 0; i < ARRAY_SIZE(mp->cck_rates); i++) 1144 if (rate->idx == mp->cck_rates[i]) 1145 return true; 1146 1147 for (i = 0; i < ARRAY_SIZE(mp->ofdm_rates[0]); i++) 1148 if (rate->idx == mp->ofdm_rates[mi->band][i]) 1149 return true; 1150 1151 return false; 1152 } 1153 1154 static void 1155 minstrel_downgrade_rate(struct minstrel_ht_sta *mi, u16 *idx, bool primary) 1156 { 1157 int group, orig_group; 1158 1159 orig_group = group = MI_RATE_GROUP(*idx); 1160 while (group > 0) { 1161 group--; 1162 1163 if (!mi->supported[group]) 1164 continue; 1165 1166 if (minstrel_mcs_groups[group].streams > 1167 minstrel_mcs_groups[orig_group].streams) 1168 continue; 1169 1170 if (primary) 1171 *idx = mi->groups[group].max_group_tp_rate[0]; 1172 else 1173 *idx = mi->groups[group].max_group_tp_rate[1]; 1174 break; 1175 } 1176 } 1177 1178 static void 1179 minstrel_aggr_check(struct ieee80211_sta *pubsta, struct sk_buff *skb) 1180 { 1181 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 1182 struct sta_info *sta = container_of(pubsta, struct sta_info, sta); 1183 u16 tid; 1184 1185 if (skb_get_queue_mapping(skb) == IEEE80211_AC_VO) 1186 return; 1187 1188 if (unlikely(!ieee80211_is_data_qos(hdr->frame_control))) 1189 return; 1190 1191 if (unlikely(skb->protocol == cpu_to_be16(ETH_P_PAE))) 1192 return; 1193 1194 tid = ieee80211_get_tid(hdr); 1195 if (likely(sta->ampdu_mlme.tid_tx[tid])) 1196 return; 1197 1198 ieee80211_start_tx_ba_session(pubsta, tid, 0); 1199 } 1200 1201 static void 1202 minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband, 1203 void *priv_sta, struct ieee80211_tx_status *st) 1204 { 1205 struct ieee80211_tx_info *info = st->info; 1206 struct minstrel_ht_sta *mi = priv_sta; 1207 struct ieee80211_tx_rate *ar = info->status.rates; 1208 struct minstrel_rate_stats *rate, *rate2; 1209 struct minstrel_priv *mp = priv; 1210 u32 update_interval = mp->update_interval; 1211 bool last, update = false; 1212 int i; 1213 1214 /* This packet was aggregated but doesn't carry status info */ 1215 if ((info->flags & IEEE80211_TX_CTL_AMPDU) && 1216 !(info->flags & IEEE80211_TX_STAT_AMPDU)) 1217 return; 1218 1219 if (!(info->flags & IEEE80211_TX_STAT_AMPDU)) { 1220 info->status.ampdu_ack_len = 1221 (info->flags & IEEE80211_TX_STAT_ACK ? 1 : 0); 1222 info->status.ampdu_len = 1; 1223 } 1224 1225 /* wraparound */ 1226 if (mi->total_packets >= ~0 - info->status.ampdu_len) { 1227 mi->total_packets = 0; 1228 mi->sample_packets = 0; 1229 } 1230 1231 mi->total_packets += info->status.ampdu_len; 1232 if (info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE) 1233 mi->sample_packets += info->status.ampdu_len; 1234 1235 mi->ampdu_packets++; 1236 mi->ampdu_len += info->status.ampdu_len; 1237 1238 last = !minstrel_ht_txstat_valid(mp, mi, &ar[0]); 1239 for (i = 0; !last; i++) { 1240 last = (i == IEEE80211_TX_MAX_RATES - 1) || 1241 !minstrel_ht_txstat_valid(mp, mi, &ar[i + 1]); 1242 1243 rate = minstrel_ht_get_stats(mp, mi, &ar[i]); 1244 if (last) 1245 rate->success += info->status.ampdu_ack_len; 1246 1247 rate->attempts += ar[i].count * info->status.ampdu_len; 1248 } 1249 1250 if (mp->hw->max_rates > 1) { 1251 /* 1252 * check for sudden death of spatial multiplexing, 1253 * downgrade to a lower number of streams if necessary. 1254 */ 1255 rate = minstrel_get_ratestats(mi, mi->max_tp_rate[0]); 1256 if (rate->attempts > 30 && 1257 rate->success < rate->attempts / 4) { 1258 minstrel_downgrade_rate(mi, &mi->max_tp_rate[0], true); 1259 update = true; 1260 } 1261 1262 rate2 = minstrel_get_ratestats(mi, mi->max_tp_rate[1]); 1263 if (rate2->attempts > 30 && 1264 rate2->success < rate2->attempts / 4) { 1265 minstrel_downgrade_rate(mi, &mi->max_tp_rate[1], false); 1266 update = true; 1267 } 1268 } 1269 1270 if (time_after(jiffies, mi->last_stats_update + update_interval)) { 1271 update = true; 1272 minstrel_ht_update_stats(mp, mi); 1273 } 1274 1275 if (update) 1276 minstrel_ht_update_rates(mp, mi); 1277 } 1278 1279 static void 1280 minstrel_calc_retransmit(struct minstrel_priv *mp, struct minstrel_ht_sta *mi, 1281 int index) 1282 { 1283 struct minstrel_rate_stats *mrs; 1284 unsigned int tx_time, tx_time_rtscts, tx_time_data; 1285 unsigned int cw = mp->cw_min; 1286 unsigned int ctime = 0; 1287 unsigned int t_slot = 9; /* FIXME */ 1288 unsigned int ampdu_len = minstrel_ht_avg_ampdu_len(mi); 1289 unsigned int overhead = 0, overhead_rtscts = 0; 1290 1291 mrs = minstrel_get_ratestats(mi, index); 1292 if (mrs->prob_avg < MINSTREL_FRAC(1, 10)) { 1293 mrs->retry_count = 1; 1294 mrs->retry_count_rtscts = 1; 1295 return; 1296 } 1297 1298 mrs->retry_count = 2; 1299 mrs->retry_count_rtscts = 2; 1300 mrs->retry_updated = true; 1301 1302 tx_time_data = minstrel_get_duration(index) * ampdu_len / 1000; 1303 1304 /* Contention time for first 2 tries */ 1305 ctime = (t_slot * cw) >> 1; 1306 cw = min((cw << 1) | 1, mp->cw_max); 1307 ctime += (t_slot * cw) >> 1; 1308 cw = min((cw << 1) | 1, mp->cw_max); 1309 1310 if (minstrel_ht_is_legacy_group(MI_RATE_GROUP(index))) { 1311 overhead = mi->overhead_legacy; 1312 overhead_rtscts = mi->overhead_legacy_rtscts; 1313 } else { 1314 overhead = mi->overhead; 1315 overhead_rtscts = mi->overhead_rtscts; 1316 } 1317 1318 /* Total TX time for data and Contention after first 2 tries */ 1319 tx_time = ctime + 2 * (overhead + tx_time_data); 1320 tx_time_rtscts = ctime + 2 * (overhead_rtscts + tx_time_data); 1321 1322 /* See how many more tries we can fit inside segment size */ 1323 do { 1324 /* Contention time for this try */ 1325 ctime = (t_slot * cw) >> 1; 1326 cw = min((cw << 1) | 1, mp->cw_max); 1327 1328 /* Total TX time after this try */ 1329 tx_time += ctime + overhead + tx_time_data; 1330 tx_time_rtscts += ctime + overhead_rtscts + tx_time_data; 1331 1332 if (tx_time_rtscts < mp->segment_size) 1333 mrs->retry_count_rtscts++; 1334 } while ((tx_time < mp->segment_size) && 1335 (++mrs->retry_count < mp->max_retry)); 1336 } 1337 1338 1339 static void 1340 minstrel_ht_set_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi, 1341 struct ieee80211_sta_rates *ratetbl, int offset, int index) 1342 { 1343 int group_idx = MI_RATE_GROUP(index); 1344 const struct mcs_group *group = &minstrel_mcs_groups[group_idx]; 1345 struct minstrel_rate_stats *mrs; 1346 u8 idx; 1347 u16 flags = group->flags; 1348 1349 mrs = minstrel_get_ratestats(mi, index); 1350 if (!mrs->retry_updated) 1351 minstrel_calc_retransmit(mp, mi, index); 1352 1353 if (mrs->prob_avg < MINSTREL_FRAC(20, 100) || !mrs->retry_count) { 1354 ratetbl->rate[offset].count = 2; 1355 ratetbl->rate[offset].count_rts = 2; 1356 ratetbl->rate[offset].count_cts = 2; 1357 } else { 1358 ratetbl->rate[offset].count = mrs->retry_count; 1359 ratetbl->rate[offset].count_cts = mrs->retry_count; 1360 ratetbl->rate[offset].count_rts = mrs->retry_count_rtscts; 1361 } 1362 1363 index = MI_RATE_IDX(index); 1364 if (group_idx == MINSTREL_CCK_GROUP) 1365 idx = mp->cck_rates[index % ARRAY_SIZE(mp->cck_rates)]; 1366 else if (group_idx == MINSTREL_OFDM_GROUP) 1367 idx = mp->ofdm_rates[mi->band][index % 1368 ARRAY_SIZE(mp->ofdm_rates[0])]; 1369 else if (flags & IEEE80211_TX_RC_VHT_MCS) 1370 idx = ((group->streams - 1) << 4) | 1371 (index & 0xF); 1372 else 1373 idx = index + (group->streams - 1) * 8; 1374 1375 /* enable RTS/CTS if needed: 1376 * - if station is in dynamic SMPS (and streams > 1) 1377 * - for fallback rates, to increase chances of getting through 1378 */ 1379 if (offset > 0 || 1380 (mi->sta->smps_mode == IEEE80211_SMPS_DYNAMIC && 1381 group->streams > 1)) { 1382 ratetbl->rate[offset].count = ratetbl->rate[offset].count_rts; 1383 flags |= IEEE80211_TX_RC_USE_RTS_CTS; 1384 } 1385 1386 ratetbl->rate[offset].idx = idx; 1387 ratetbl->rate[offset].flags = flags; 1388 } 1389 1390 static inline int 1391 minstrel_ht_get_prob_avg(struct minstrel_ht_sta *mi, int rate) 1392 { 1393 int group = MI_RATE_GROUP(rate); 1394 rate = MI_RATE_IDX(rate); 1395 return mi->groups[group].rates[rate].prob_avg; 1396 } 1397 1398 static int 1399 minstrel_ht_get_max_amsdu_len(struct minstrel_ht_sta *mi) 1400 { 1401 int group = MI_RATE_GROUP(mi->max_prob_rate); 1402 const struct mcs_group *g = &minstrel_mcs_groups[group]; 1403 int rate = MI_RATE_IDX(mi->max_prob_rate); 1404 unsigned int duration; 1405 1406 /* Disable A-MSDU if max_prob_rate is bad */ 1407 if (mi->groups[group].rates[rate].prob_avg < MINSTREL_FRAC(50, 100)) 1408 return 1; 1409 1410 duration = g->duration[rate]; 1411 duration <<= g->shift; 1412 1413 /* If the rate is slower than single-stream MCS1, make A-MSDU limit small */ 1414 if (duration > MCS_DURATION(1, 0, 52)) 1415 return 500; 1416 1417 /* 1418 * If the rate is slower than single-stream MCS4, limit A-MSDU to usual 1419 * data packet size 1420 */ 1421 if (duration > MCS_DURATION(1, 0, 104)) 1422 return 1600; 1423 1424 /* 1425 * If the rate is slower than single-stream MCS7, or if the max throughput 1426 * rate success probability is less than 75%, limit A-MSDU to twice the usual 1427 * data packet size 1428 */ 1429 if (duration > MCS_DURATION(1, 0, 260) || 1430 (minstrel_ht_get_prob_avg(mi, mi->max_tp_rate[0]) < 1431 MINSTREL_FRAC(75, 100))) 1432 return 3200; 1433 1434 /* 1435 * HT A-MPDU limits maximum MPDU size under BA agreement to 4095 bytes. 1436 * Since aggregation sessions are started/stopped without txq flush, use 1437 * the limit here to avoid the complexity of having to de-aggregate 1438 * packets in the queue. 1439 */ 1440 if (!mi->sta->vht_cap.vht_supported) 1441 return IEEE80211_MAX_MPDU_LEN_HT_BA; 1442 1443 /* unlimited */ 1444 return 0; 1445 } 1446 1447 static void 1448 minstrel_ht_update_rates(struct minstrel_priv *mp, struct minstrel_ht_sta *mi) 1449 { 1450 struct ieee80211_sta_rates *rates; 1451 int i = 0; 1452 1453 rates = kzalloc(sizeof(*rates), GFP_ATOMIC); 1454 if (!rates) 1455 return; 1456 1457 /* Start with max_tp_rate[0] */ 1458 minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_tp_rate[0]); 1459 1460 if (mp->hw->max_rates >= 3) { 1461 /* At least 3 tx rates supported, use max_tp_rate[1] next */ 1462 minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_tp_rate[1]); 1463 } 1464 1465 if (mp->hw->max_rates >= 2) { 1466 minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_prob_rate); 1467 } 1468 1469 mi->sta->max_rc_amsdu_len = minstrel_ht_get_max_amsdu_len(mi); 1470 rates->rate[i].idx = -1; 1471 rate_control_set_rates(mp->hw, mi->sta, rates); 1472 } 1473 1474 static u16 1475 minstrel_ht_get_sample_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi) 1476 { 1477 u8 seq; 1478 1479 if (mp->hw->max_rates > 1) { 1480 seq = mi->sample_seq; 1481 mi->sample_seq = (seq + 1) % ARRAY_SIZE(minstrel_sample_seq); 1482 seq = minstrel_sample_seq[seq]; 1483 } else { 1484 seq = MINSTREL_SAMPLE_TYPE_INC; 1485 } 1486 1487 return __minstrel_ht_get_sample_rate(mi, seq); 1488 } 1489 1490 static void 1491 minstrel_ht_get_rate(void *priv, struct ieee80211_sta *sta, void *priv_sta, 1492 struct ieee80211_tx_rate_control *txrc) 1493 { 1494 const struct mcs_group *sample_group; 1495 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb); 1496 struct ieee80211_tx_rate *rate = &info->status.rates[0]; 1497 struct minstrel_ht_sta *mi = priv_sta; 1498 struct minstrel_priv *mp = priv; 1499 u16 sample_idx; 1500 1501 if (!(info->flags & IEEE80211_TX_CTL_AMPDU) && 1502 !minstrel_ht_is_legacy_group(MI_RATE_GROUP(mi->max_prob_rate))) 1503 minstrel_aggr_check(sta, txrc->skb); 1504 1505 info->flags |= mi->tx_flags; 1506 1507 #ifdef CONFIG_MAC80211_DEBUGFS 1508 if (mp->fixed_rate_idx != -1) 1509 return; 1510 #endif 1511 1512 /* Don't use EAPOL frames for sampling on non-mrr hw */ 1513 if (mp->hw->max_rates == 1 && 1514 (info->control.flags & IEEE80211_TX_CTRL_PORT_CTRL_PROTO)) 1515 return; 1516 1517 if (time_is_before_jiffies(mi->sample_time)) 1518 return; 1519 1520 mi->sample_time = jiffies + MINSTREL_SAMPLE_INTERVAL; 1521 sample_idx = minstrel_ht_get_sample_rate(mp, mi); 1522 if (!sample_idx) 1523 return; 1524 1525 sample_group = &minstrel_mcs_groups[MI_RATE_GROUP(sample_idx)]; 1526 sample_idx = MI_RATE_IDX(sample_idx); 1527 1528 if (sample_group == &minstrel_mcs_groups[MINSTREL_CCK_GROUP] && 1529 (sample_idx >= 4) != txrc->short_preamble) 1530 return; 1531 1532 info->flags |= IEEE80211_TX_CTL_RATE_CTRL_PROBE; 1533 rate->count = 1; 1534 1535 if (sample_group == &minstrel_mcs_groups[MINSTREL_CCK_GROUP]) { 1536 int idx = sample_idx % ARRAY_SIZE(mp->cck_rates); 1537 rate->idx = mp->cck_rates[idx]; 1538 } else if (sample_group == &minstrel_mcs_groups[MINSTREL_OFDM_GROUP]) { 1539 int idx = sample_idx % ARRAY_SIZE(mp->ofdm_rates[0]); 1540 rate->idx = mp->ofdm_rates[mi->band][idx]; 1541 } else if (sample_group->flags & IEEE80211_TX_RC_VHT_MCS) { 1542 ieee80211_rate_set_vht(rate, MI_RATE_IDX(sample_idx), 1543 sample_group->streams); 1544 } else { 1545 rate->idx = sample_idx + (sample_group->streams - 1) * 8; 1546 } 1547 1548 rate->flags = sample_group->flags; 1549 } 1550 1551 static void 1552 minstrel_ht_update_cck(struct minstrel_priv *mp, struct minstrel_ht_sta *mi, 1553 struct ieee80211_supported_band *sband, 1554 struct ieee80211_sta *sta) 1555 { 1556 int i; 1557 1558 if (sband->band != NL80211_BAND_2GHZ) 1559 return; 1560 1561 if (sta->ht_cap.ht_supported && 1562 !ieee80211_hw_check(mp->hw, SUPPORTS_HT_CCK_RATES)) 1563 return; 1564 1565 for (i = 0; i < 4; i++) { 1566 if (mp->cck_rates[i] == 0xff || 1567 !rate_supported(sta, sband->band, mp->cck_rates[i])) 1568 continue; 1569 1570 mi->supported[MINSTREL_CCK_GROUP] |= BIT(i); 1571 if (sband->bitrates[i].flags & IEEE80211_RATE_SHORT_PREAMBLE) 1572 mi->supported[MINSTREL_CCK_GROUP] |= BIT(i + 4); 1573 } 1574 } 1575 1576 static void 1577 minstrel_ht_update_ofdm(struct minstrel_priv *mp, struct minstrel_ht_sta *mi, 1578 struct ieee80211_supported_band *sband, 1579 struct ieee80211_sta *sta) 1580 { 1581 const u8 *rates; 1582 int i; 1583 1584 if (sta->ht_cap.ht_supported) 1585 return; 1586 1587 rates = mp->ofdm_rates[sband->band]; 1588 for (i = 0; i < ARRAY_SIZE(mp->ofdm_rates[0]); i++) { 1589 if (rates[i] == 0xff || 1590 !rate_supported(sta, sband->band, rates[i])) 1591 continue; 1592 1593 mi->supported[MINSTREL_OFDM_GROUP] |= BIT(i); 1594 } 1595 } 1596 1597 static void 1598 minstrel_ht_update_caps(void *priv, struct ieee80211_supported_band *sband, 1599 struct cfg80211_chan_def *chandef, 1600 struct ieee80211_sta *sta, void *priv_sta) 1601 { 1602 struct minstrel_priv *mp = priv; 1603 struct minstrel_ht_sta *mi = priv_sta; 1604 struct ieee80211_mcs_info *mcs = &sta->ht_cap.mcs; 1605 u16 ht_cap = sta->ht_cap.cap; 1606 struct ieee80211_sta_vht_cap *vht_cap = &sta->vht_cap; 1607 const struct ieee80211_rate *ctl_rate; 1608 bool ldpc, erp; 1609 int use_vht; 1610 int n_supported = 0; 1611 int ack_dur; 1612 int stbc; 1613 int i; 1614 1615 BUILD_BUG_ON(ARRAY_SIZE(minstrel_mcs_groups) != MINSTREL_GROUPS_NB); 1616 1617 if (vht_cap->vht_supported) 1618 use_vht = vht_cap->vht_mcs.tx_mcs_map != cpu_to_le16(~0); 1619 else 1620 use_vht = 0; 1621 1622 memset(mi, 0, sizeof(*mi)); 1623 1624 mi->sta = sta; 1625 mi->band = sband->band; 1626 mi->last_stats_update = jiffies; 1627 1628 ack_dur = ieee80211_frame_duration(sband->band, 10, 60, 1, 1, 0); 1629 mi->overhead = ieee80211_frame_duration(sband->band, 0, 60, 1, 1, 0); 1630 mi->overhead += ack_dur; 1631 mi->overhead_rtscts = mi->overhead + 2 * ack_dur; 1632 1633 ctl_rate = &sband->bitrates[rate_lowest_index(sband, sta)]; 1634 erp = ctl_rate->flags & IEEE80211_RATE_ERP_G; 1635 ack_dur = ieee80211_frame_duration(sband->band, 10, 1636 ctl_rate->bitrate, erp, 1, 1637 ieee80211_chandef_get_shift(chandef)); 1638 mi->overhead_legacy = ack_dur; 1639 mi->overhead_legacy_rtscts = mi->overhead_legacy + 2 * ack_dur; 1640 1641 mi->avg_ampdu_len = MINSTREL_FRAC(1, 1); 1642 1643 if (!use_vht) { 1644 stbc = (ht_cap & IEEE80211_HT_CAP_RX_STBC) >> 1645 IEEE80211_HT_CAP_RX_STBC_SHIFT; 1646 1647 ldpc = ht_cap & IEEE80211_HT_CAP_LDPC_CODING; 1648 } else { 1649 stbc = (vht_cap->cap & IEEE80211_VHT_CAP_RXSTBC_MASK) >> 1650 IEEE80211_VHT_CAP_RXSTBC_SHIFT; 1651 1652 ldpc = vht_cap->cap & IEEE80211_VHT_CAP_RXLDPC; 1653 } 1654 1655 mi->tx_flags |= stbc << IEEE80211_TX_CTL_STBC_SHIFT; 1656 if (ldpc) 1657 mi->tx_flags |= IEEE80211_TX_CTL_LDPC; 1658 1659 for (i = 0; i < ARRAY_SIZE(mi->groups); i++) { 1660 u32 gflags = minstrel_mcs_groups[i].flags; 1661 int bw, nss; 1662 1663 mi->supported[i] = 0; 1664 if (minstrel_ht_is_legacy_group(i)) 1665 continue; 1666 1667 if (gflags & IEEE80211_TX_RC_SHORT_GI) { 1668 if (gflags & IEEE80211_TX_RC_40_MHZ_WIDTH) { 1669 if (!(ht_cap & IEEE80211_HT_CAP_SGI_40)) 1670 continue; 1671 } else { 1672 if (!(ht_cap & IEEE80211_HT_CAP_SGI_20)) 1673 continue; 1674 } 1675 } 1676 1677 if (gflags & IEEE80211_TX_RC_40_MHZ_WIDTH && 1678 sta->bandwidth < IEEE80211_STA_RX_BW_40) 1679 continue; 1680 1681 nss = minstrel_mcs_groups[i].streams; 1682 1683 /* Mark MCS > 7 as unsupported if STA is in static SMPS mode */ 1684 if (sta->smps_mode == IEEE80211_SMPS_STATIC && nss > 1) 1685 continue; 1686 1687 /* HT rate */ 1688 if (gflags & IEEE80211_TX_RC_MCS) { 1689 if (use_vht && minstrel_vht_only) 1690 continue; 1691 1692 mi->supported[i] = mcs->rx_mask[nss - 1]; 1693 if (mi->supported[i]) 1694 n_supported++; 1695 continue; 1696 } 1697 1698 /* VHT rate */ 1699 if (!vht_cap->vht_supported || 1700 WARN_ON(!(gflags & IEEE80211_TX_RC_VHT_MCS)) || 1701 WARN_ON(gflags & IEEE80211_TX_RC_160_MHZ_WIDTH)) 1702 continue; 1703 1704 if (gflags & IEEE80211_TX_RC_80_MHZ_WIDTH) { 1705 if (sta->bandwidth < IEEE80211_STA_RX_BW_80 || 1706 ((gflags & IEEE80211_TX_RC_SHORT_GI) && 1707 !(vht_cap->cap & IEEE80211_VHT_CAP_SHORT_GI_80))) { 1708 continue; 1709 } 1710 } 1711 1712 if (gflags & IEEE80211_TX_RC_40_MHZ_WIDTH) 1713 bw = BW_40; 1714 else if (gflags & IEEE80211_TX_RC_80_MHZ_WIDTH) 1715 bw = BW_80; 1716 else 1717 bw = BW_20; 1718 1719 mi->supported[i] = minstrel_get_valid_vht_rates(bw, nss, 1720 vht_cap->vht_mcs.tx_mcs_map); 1721 1722 if (mi->supported[i]) 1723 n_supported++; 1724 } 1725 1726 minstrel_ht_update_cck(mp, mi, sband, sta); 1727 minstrel_ht_update_ofdm(mp, mi, sband, sta); 1728 1729 /* create an initial rate table with the lowest supported rates */ 1730 minstrel_ht_update_stats(mp, mi); 1731 minstrel_ht_update_rates(mp, mi); 1732 } 1733 1734 static void 1735 minstrel_ht_rate_init(void *priv, struct ieee80211_supported_band *sband, 1736 struct cfg80211_chan_def *chandef, 1737 struct ieee80211_sta *sta, void *priv_sta) 1738 { 1739 minstrel_ht_update_caps(priv, sband, chandef, sta, priv_sta); 1740 } 1741 1742 static void 1743 minstrel_ht_rate_update(void *priv, struct ieee80211_supported_band *sband, 1744 struct cfg80211_chan_def *chandef, 1745 struct ieee80211_sta *sta, void *priv_sta, 1746 u32 changed) 1747 { 1748 minstrel_ht_update_caps(priv, sband, chandef, sta, priv_sta); 1749 } 1750 1751 static void * 1752 minstrel_ht_alloc_sta(void *priv, struct ieee80211_sta *sta, gfp_t gfp) 1753 { 1754 struct ieee80211_supported_band *sband; 1755 struct minstrel_ht_sta *mi; 1756 struct minstrel_priv *mp = priv; 1757 struct ieee80211_hw *hw = mp->hw; 1758 int max_rates = 0; 1759 int i; 1760 1761 for (i = 0; i < NUM_NL80211_BANDS; i++) { 1762 sband = hw->wiphy->bands[i]; 1763 if (sband && sband->n_bitrates > max_rates) 1764 max_rates = sband->n_bitrates; 1765 } 1766 1767 return kzalloc(sizeof(*mi), gfp); 1768 } 1769 1770 static void 1771 minstrel_ht_free_sta(void *priv, struct ieee80211_sta *sta, void *priv_sta) 1772 { 1773 kfree(priv_sta); 1774 } 1775 1776 static void 1777 minstrel_ht_fill_rate_array(u8 *dest, struct ieee80211_supported_band *sband, 1778 const s16 *bitrates, int n_rates, u32 rate_flags) 1779 { 1780 int i, j; 1781 1782 for (i = 0; i < sband->n_bitrates; i++) { 1783 struct ieee80211_rate *rate = &sband->bitrates[i]; 1784 1785 if ((rate_flags & sband->bitrates[i].flags) != rate_flags) 1786 continue; 1787 1788 for (j = 0; j < n_rates; j++) { 1789 if (rate->bitrate != bitrates[j]) 1790 continue; 1791 1792 dest[j] = i; 1793 break; 1794 } 1795 } 1796 } 1797 1798 static void 1799 minstrel_ht_init_cck_rates(struct minstrel_priv *mp) 1800 { 1801 static const s16 bitrates[4] = { 10, 20, 55, 110 }; 1802 struct ieee80211_supported_band *sband; 1803 u32 rate_flags = ieee80211_chandef_rate_flags(&mp->hw->conf.chandef); 1804 1805 memset(mp->cck_rates, 0xff, sizeof(mp->cck_rates)); 1806 sband = mp->hw->wiphy->bands[NL80211_BAND_2GHZ]; 1807 if (!sband) 1808 return; 1809 1810 BUILD_BUG_ON(ARRAY_SIZE(mp->cck_rates) != ARRAY_SIZE(bitrates)); 1811 minstrel_ht_fill_rate_array(mp->cck_rates, sband, 1812 minstrel_cck_bitrates, 1813 ARRAY_SIZE(minstrel_cck_bitrates), 1814 rate_flags); 1815 } 1816 1817 static void 1818 minstrel_ht_init_ofdm_rates(struct minstrel_priv *mp, enum nl80211_band band) 1819 { 1820 static const s16 bitrates[8] = { 60, 90, 120, 180, 240, 360, 480, 540 }; 1821 struct ieee80211_supported_band *sband; 1822 u32 rate_flags = ieee80211_chandef_rate_flags(&mp->hw->conf.chandef); 1823 1824 memset(mp->ofdm_rates[band], 0xff, sizeof(mp->ofdm_rates[band])); 1825 sband = mp->hw->wiphy->bands[band]; 1826 if (!sband) 1827 return; 1828 1829 BUILD_BUG_ON(ARRAY_SIZE(mp->ofdm_rates[band]) != ARRAY_SIZE(bitrates)); 1830 minstrel_ht_fill_rate_array(mp->ofdm_rates[band], sband, 1831 minstrel_ofdm_bitrates, 1832 ARRAY_SIZE(minstrel_ofdm_bitrates), 1833 rate_flags); 1834 } 1835 1836 static void * 1837 minstrel_ht_alloc(struct ieee80211_hw *hw) 1838 { 1839 struct minstrel_priv *mp; 1840 int i; 1841 1842 mp = kzalloc(sizeof(struct minstrel_priv), GFP_ATOMIC); 1843 if (!mp) 1844 return NULL; 1845 1846 /* contention window settings 1847 * Just an approximation. Using the per-queue values would complicate 1848 * the calculations and is probably unnecessary */ 1849 mp->cw_min = 15; 1850 mp->cw_max = 1023; 1851 1852 /* maximum time that the hw is allowed to stay in one MRR segment */ 1853 mp->segment_size = 6000; 1854 1855 if (hw->max_rate_tries > 0) 1856 mp->max_retry = hw->max_rate_tries; 1857 else 1858 /* safe default, does not necessarily have to match hw properties */ 1859 mp->max_retry = 7; 1860 1861 if (hw->max_rates >= 4) 1862 mp->has_mrr = true; 1863 1864 mp->hw = hw; 1865 mp->update_interval = HZ / 20; 1866 1867 minstrel_ht_init_cck_rates(mp); 1868 for (i = 0; i < ARRAY_SIZE(mp->hw->wiphy->bands); i++) 1869 minstrel_ht_init_ofdm_rates(mp, i); 1870 1871 return mp; 1872 } 1873 1874 #ifdef CONFIG_MAC80211_DEBUGFS 1875 static void minstrel_ht_add_debugfs(struct ieee80211_hw *hw, void *priv, 1876 struct dentry *debugfsdir) 1877 { 1878 struct minstrel_priv *mp = priv; 1879 1880 mp->fixed_rate_idx = (u32) -1; 1881 debugfs_create_u32("fixed_rate_idx", S_IRUGO | S_IWUGO, debugfsdir, 1882 &mp->fixed_rate_idx); 1883 } 1884 #endif 1885 1886 static void 1887 minstrel_ht_free(void *priv) 1888 { 1889 kfree(priv); 1890 } 1891 1892 static u32 minstrel_ht_get_expected_throughput(void *priv_sta) 1893 { 1894 struct minstrel_ht_sta *mi = priv_sta; 1895 int i, j, prob, tp_avg; 1896 1897 i = MI_RATE_GROUP(mi->max_tp_rate[0]); 1898 j = MI_RATE_IDX(mi->max_tp_rate[0]); 1899 prob = mi->groups[i].rates[j].prob_avg; 1900 1901 /* convert tp_avg from pkt per second in kbps */ 1902 tp_avg = minstrel_ht_get_tp_avg(mi, i, j, prob) * 10; 1903 tp_avg = tp_avg * AVG_PKT_SIZE * 8 / 1024; 1904 1905 return tp_avg; 1906 } 1907 1908 static const struct rate_control_ops mac80211_minstrel_ht = { 1909 .name = "minstrel_ht", 1910 .tx_status_ext = minstrel_ht_tx_status, 1911 .get_rate = minstrel_ht_get_rate, 1912 .rate_init = minstrel_ht_rate_init, 1913 .rate_update = minstrel_ht_rate_update, 1914 .alloc_sta = minstrel_ht_alloc_sta, 1915 .free_sta = minstrel_ht_free_sta, 1916 .alloc = minstrel_ht_alloc, 1917 .free = minstrel_ht_free, 1918 #ifdef CONFIG_MAC80211_DEBUGFS 1919 .add_debugfs = minstrel_ht_add_debugfs, 1920 .add_sta_debugfs = minstrel_ht_add_sta_debugfs, 1921 #endif 1922 .get_expected_throughput = minstrel_ht_get_expected_throughput, 1923 }; 1924 1925 1926 static void __init init_sample_table(void) 1927 { 1928 int col, i, new_idx; 1929 u8 rnd[MCS_GROUP_RATES]; 1930 1931 memset(sample_table, 0xff, sizeof(sample_table)); 1932 for (col = 0; col < SAMPLE_COLUMNS; col++) { 1933 prandom_bytes(rnd, sizeof(rnd)); 1934 for (i = 0; i < MCS_GROUP_RATES; i++) { 1935 new_idx = (i + rnd[i]) % MCS_GROUP_RATES; 1936 while (sample_table[col][new_idx] != 0xff) 1937 new_idx = (new_idx + 1) % MCS_GROUP_RATES; 1938 1939 sample_table[col][new_idx] = i; 1940 } 1941 } 1942 } 1943 1944 int __init 1945 rc80211_minstrel_init(void) 1946 { 1947 init_sample_table(); 1948 return ieee80211_rate_control_register(&mac80211_minstrel_ht); 1949 } 1950 1951 void 1952 rc80211_minstrel_exit(void) 1953 { 1954 ieee80211_rate_control_unregister(&mac80211_minstrel_ht); 1955 } 1956