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 struct minstrel_mcs_group_data *mg; 809 u8 type = MINSTREL_SAMPLE_TYPE_INC; 810 int i, index = 0; 811 u8 group; 812 813 group = mi->sample[type].sample_group; 814 for (i = 0; i < ARRAY_SIZE(minstrel_mcs_groups); i++) { 815 group = (group + 1) % ARRAY_SIZE(minstrel_mcs_groups); 816 mg = &mi->groups[group]; 817 818 index = minstrel_ht_group_min_rate_offset(mi, group, 819 fast_rate_dur); 820 if (index < 0) 821 continue; 822 823 index = MI_RATE(group, index & 0xf); 824 if (!minstrel_ht_find_sample_rate(mi, type, index)) 825 goto out; 826 } 827 index = 0; 828 829 out: 830 mi->sample[type].sample_group = group; 831 832 return index; 833 } 834 835 static int 836 minstrel_ht_next_group_sample_rate(struct minstrel_ht_sta *mi, int group, 837 u16 supported, int offset) 838 { 839 struct minstrel_mcs_group_data *mg = &mi->groups[group]; 840 u16 idx; 841 int i; 842 843 for (i = 0; i < MCS_GROUP_RATES; i++) { 844 idx = sample_table[mg->column][mg->index]; 845 if (++mg->index >= MCS_GROUP_RATES) { 846 mg->index = 0; 847 if (++mg->column >= ARRAY_SIZE(sample_table)) 848 mg->column = 0; 849 } 850 851 if (idx < offset) 852 continue; 853 854 if (!(supported & BIT(idx))) 855 continue; 856 857 return MI_RATE(group, idx); 858 } 859 860 return -1; 861 } 862 863 /* 864 * Jump rates: 865 * Sample random rates, use those that are faster than the highest 866 * currently selected rate. Rates between the fastest and the slowest 867 * get sorted into the slow sample bucket, but only if it has room 868 */ 869 static u16 870 minstrel_ht_next_jump_rate(struct minstrel_ht_sta *mi, u32 fast_rate_dur, 871 u32 slow_rate_dur, int *slow_rate_ofs) 872 { 873 struct minstrel_mcs_group_data *mg; 874 struct minstrel_rate_stats *mrs; 875 u32 max_duration = slow_rate_dur; 876 int i, index, offset; 877 u16 *slow_rates; 878 u16 supported; 879 u32 duration; 880 u8 group; 881 882 if (*slow_rate_ofs >= MINSTREL_SAMPLE_RATES) 883 max_duration = fast_rate_dur; 884 885 slow_rates = mi->sample[MINSTREL_SAMPLE_TYPE_SLOW].sample_rates; 886 group = mi->sample[MINSTREL_SAMPLE_TYPE_JUMP].sample_group; 887 for (i = 0; i < ARRAY_SIZE(minstrel_mcs_groups); i++) { 888 u8 type; 889 890 group = (group + 1) % ARRAY_SIZE(minstrel_mcs_groups); 891 mg = &mi->groups[group]; 892 893 supported = mi->supported[group]; 894 if (!supported) 895 continue; 896 897 offset = minstrel_ht_group_min_rate_offset(mi, group, 898 max_duration); 899 if (offset < 0) 900 continue; 901 902 index = minstrel_ht_next_group_sample_rate(mi, group, supported, 903 offset); 904 if (index < 0) 905 continue; 906 907 duration = minstrel_get_duration(index); 908 if (duration < fast_rate_dur) 909 type = MINSTREL_SAMPLE_TYPE_JUMP; 910 else 911 type = MINSTREL_SAMPLE_TYPE_SLOW; 912 913 if (minstrel_ht_find_sample_rate(mi, type, index)) 914 continue; 915 916 if (type == MINSTREL_SAMPLE_TYPE_JUMP) 917 goto found; 918 919 if (*slow_rate_ofs >= MINSTREL_SAMPLE_RATES) 920 continue; 921 922 if (duration >= slow_rate_dur) 923 continue; 924 925 /* skip slow rates with high success probability */ 926 mrs = minstrel_get_ratestats(mi, index); 927 if (mrs->prob_avg > MINSTREL_FRAC(95, 100)) 928 continue; 929 930 slow_rates[(*slow_rate_ofs)++] = index; 931 if (*slow_rate_ofs >= MINSTREL_SAMPLE_RATES) 932 max_duration = fast_rate_dur; 933 } 934 index = 0; 935 936 found: 937 mi->sample[MINSTREL_SAMPLE_TYPE_JUMP].sample_group = group; 938 939 return index; 940 } 941 942 static void 943 minstrel_ht_refill_sample_rates(struct minstrel_ht_sta *mi) 944 { 945 u32 prob_dur = minstrel_get_duration(mi->max_prob_rate); 946 u32 tp_dur = minstrel_get_duration(mi->max_tp_rate[0]); 947 u32 tp2_dur = minstrel_get_duration(mi->max_tp_rate[1]); 948 u32 fast_rate_dur = min(min(tp_dur, tp2_dur), prob_dur); 949 u32 slow_rate_dur = max(max(tp_dur, tp2_dur), prob_dur); 950 u16 *rates; 951 int i, j; 952 953 rates = mi->sample[MINSTREL_SAMPLE_TYPE_INC].sample_rates; 954 i = minstrel_ht_move_sample_rates(mi, MINSTREL_SAMPLE_TYPE_INC, 955 fast_rate_dur, slow_rate_dur); 956 while (i < MINSTREL_SAMPLE_RATES) { 957 rates[i] = minstrel_ht_next_inc_rate(mi, tp_dur); 958 if (!rates[i]) 959 break; 960 961 i++; 962 } 963 964 rates = mi->sample[MINSTREL_SAMPLE_TYPE_JUMP].sample_rates; 965 i = minstrel_ht_move_sample_rates(mi, MINSTREL_SAMPLE_TYPE_JUMP, 966 fast_rate_dur, slow_rate_dur); 967 j = minstrel_ht_move_sample_rates(mi, MINSTREL_SAMPLE_TYPE_SLOW, 968 fast_rate_dur, slow_rate_dur); 969 while (i < MINSTREL_SAMPLE_RATES) { 970 rates[i] = minstrel_ht_next_jump_rate(mi, fast_rate_dur, 971 slow_rate_dur, &j); 972 if (!rates[i]) 973 break; 974 975 i++; 976 } 977 978 for (i = 0; i < ARRAY_SIZE(mi->sample); i++) 979 memcpy(mi->sample[i].cur_sample_rates, mi->sample[i].sample_rates, 980 sizeof(mi->sample[i].cur_sample_rates)); 981 } 982 983 984 /* 985 * Update rate statistics and select new primary rates 986 * 987 * Rules for rate selection: 988 * - max_prob_rate must use only one stream, as a tradeoff between delivery 989 * probability and throughput during strong fluctuations 990 * - as long as the max prob rate has a probability of more than 75%, pick 991 * higher throughput rates, even if the probablity is a bit lower 992 */ 993 static void 994 minstrel_ht_update_stats(struct minstrel_priv *mp, struct minstrel_ht_sta *mi) 995 { 996 struct minstrel_mcs_group_data *mg; 997 struct minstrel_rate_stats *mrs; 998 int group, i, j, cur_prob; 999 u16 tmp_mcs_tp_rate[MAX_THR_RATES], tmp_group_tp_rate[MAX_THR_RATES]; 1000 u16 tmp_legacy_tp_rate[MAX_THR_RATES], tmp_max_prob_rate; 1001 u16 index; 1002 bool ht_supported = mi->sta->ht_cap.ht_supported; 1003 1004 if (mi->ampdu_packets > 0) { 1005 if (!ieee80211_hw_check(mp->hw, TX_STATUS_NO_AMPDU_LEN)) 1006 mi->avg_ampdu_len = minstrel_ewma(mi->avg_ampdu_len, 1007 MINSTREL_FRAC(mi->ampdu_len, mi->ampdu_packets), 1008 EWMA_LEVEL); 1009 else 1010 mi->avg_ampdu_len = 0; 1011 mi->ampdu_len = 0; 1012 mi->ampdu_packets = 0; 1013 } 1014 1015 if (mi->supported[MINSTREL_CCK_GROUP]) 1016 group = MINSTREL_CCK_GROUP; 1017 else if (mi->supported[MINSTREL_OFDM_GROUP]) 1018 group = MINSTREL_OFDM_GROUP; 1019 else 1020 group = 0; 1021 1022 index = MI_RATE(group, 0); 1023 for (j = 0; j < ARRAY_SIZE(tmp_legacy_tp_rate); j++) 1024 tmp_legacy_tp_rate[j] = index; 1025 1026 if (mi->supported[MINSTREL_VHT_GROUP_0]) 1027 group = MINSTREL_VHT_GROUP_0; 1028 else if (ht_supported) 1029 group = MINSTREL_HT_GROUP_0; 1030 else if (mi->supported[MINSTREL_CCK_GROUP]) 1031 group = MINSTREL_CCK_GROUP; 1032 else 1033 group = MINSTREL_OFDM_GROUP; 1034 1035 index = MI_RATE(group, 0); 1036 tmp_max_prob_rate = index; 1037 for (j = 0; j < ARRAY_SIZE(tmp_mcs_tp_rate); j++) 1038 tmp_mcs_tp_rate[j] = index; 1039 1040 /* Find best rate sets within all MCS groups*/ 1041 for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) { 1042 u16 *tp_rate = tmp_mcs_tp_rate; 1043 u16 last_prob = 0; 1044 1045 mg = &mi->groups[group]; 1046 if (!mi->supported[group]) 1047 continue; 1048 1049 /* (re)Initialize group rate indexes */ 1050 for(j = 0; j < MAX_THR_RATES; j++) 1051 tmp_group_tp_rate[j] = MI_RATE(group, 0); 1052 1053 if (group == MINSTREL_CCK_GROUP && ht_supported) 1054 tp_rate = tmp_legacy_tp_rate; 1055 1056 for (i = MCS_GROUP_RATES - 1; i >= 0; i--) { 1057 if (!(mi->supported[group] & BIT(i))) 1058 continue; 1059 1060 index = MI_RATE(group, i); 1061 1062 mrs = &mg->rates[i]; 1063 mrs->retry_updated = false; 1064 minstrel_ht_calc_rate_stats(mp, mrs); 1065 1066 if (mrs->att_hist) 1067 last_prob = max(last_prob, mrs->prob_avg); 1068 else 1069 mrs->prob_avg = max(last_prob, mrs->prob_avg); 1070 cur_prob = mrs->prob_avg; 1071 1072 if (minstrel_ht_get_tp_avg(mi, group, i, cur_prob) == 0) 1073 continue; 1074 1075 /* Find max throughput rate set */ 1076 minstrel_ht_sort_best_tp_rates(mi, index, tp_rate); 1077 1078 /* Find max throughput rate set within a group */ 1079 minstrel_ht_sort_best_tp_rates(mi, index, 1080 tmp_group_tp_rate); 1081 } 1082 1083 memcpy(mg->max_group_tp_rate, tmp_group_tp_rate, 1084 sizeof(mg->max_group_tp_rate)); 1085 } 1086 1087 /* Assign new rate set per sta */ 1088 minstrel_ht_assign_best_tp_rates(mi, tmp_mcs_tp_rate, 1089 tmp_legacy_tp_rate); 1090 memcpy(mi->max_tp_rate, tmp_mcs_tp_rate, sizeof(mi->max_tp_rate)); 1091 1092 for (group = 0; group < ARRAY_SIZE(minstrel_mcs_groups); group++) { 1093 if (!mi->supported[group]) 1094 continue; 1095 1096 mg = &mi->groups[group]; 1097 mg->max_group_prob_rate = MI_RATE(group, 0); 1098 1099 for (i = 0; i < MCS_GROUP_RATES; i++) { 1100 if (!(mi->supported[group] & BIT(i))) 1101 continue; 1102 1103 index = MI_RATE(group, i); 1104 1105 /* Find max probability rate per group and global */ 1106 minstrel_ht_set_best_prob_rate(mi, &tmp_max_prob_rate, 1107 index); 1108 } 1109 } 1110 1111 mi->max_prob_rate = tmp_max_prob_rate; 1112 1113 /* Try to increase robustness of max_prob_rate*/ 1114 minstrel_ht_prob_rate_reduce_streams(mi); 1115 minstrel_ht_refill_sample_rates(mi); 1116 1117 #ifdef CONFIG_MAC80211_DEBUGFS 1118 /* use fixed index if set */ 1119 if (mp->fixed_rate_idx != -1) { 1120 for (i = 0; i < 4; i++) 1121 mi->max_tp_rate[i] = mp->fixed_rate_idx; 1122 mi->max_prob_rate = mp->fixed_rate_idx; 1123 } 1124 #endif 1125 1126 /* Reset update timer */ 1127 mi->last_stats_update = jiffies; 1128 mi->sample_time = jiffies; 1129 } 1130 1131 static bool 1132 minstrel_ht_txstat_valid(struct minstrel_priv *mp, struct minstrel_ht_sta *mi, 1133 struct ieee80211_tx_rate *rate) 1134 { 1135 int i; 1136 1137 if (rate->idx < 0) 1138 return false; 1139 1140 if (!rate->count) 1141 return false; 1142 1143 if (rate->flags & IEEE80211_TX_RC_MCS || 1144 rate->flags & IEEE80211_TX_RC_VHT_MCS) 1145 return true; 1146 1147 for (i = 0; i < ARRAY_SIZE(mp->cck_rates); i++) 1148 if (rate->idx == mp->cck_rates[i]) 1149 return true; 1150 1151 for (i = 0; i < ARRAY_SIZE(mp->ofdm_rates[0]); i++) 1152 if (rate->idx == mp->ofdm_rates[mi->band][i]) 1153 return true; 1154 1155 return false; 1156 } 1157 1158 static void 1159 minstrel_downgrade_rate(struct minstrel_ht_sta *mi, u16 *idx, bool primary) 1160 { 1161 int group, orig_group; 1162 1163 orig_group = group = MI_RATE_GROUP(*idx); 1164 while (group > 0) { 1165 group--; 1166 1167 if (!mi->supported[group]) 1168 continue; 1169 1170 if (minstrel_mcs_groups[group].streams > 1171 minstrel_mcs_groups[orig_group].streams) 1172 continue; 1173 1174 if (primary) 1175 *idx = mi->groups[group].max_group_tp_rate[0]; 1176 else 1177 *idx = mi->groups[group].max_group_tp_rate[1]; 1178 break; 1179 } 1180 } 1181 1182 static void 1183 minstrel_aggr_check(struct ieee80211_sta *pubsta, struct sk_buff *skb) 1184 { 1185 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; 1186 struct sta_info *sta = container_of(pubsta, struct sta_info, sta); 1187 u16 tid; 1188 1189 if (skb_get_queue_mapping(skb) == IEEE80211_AC_VO) 1190 return; 1191 1192 if (unlikely(!ieee80211_is_data_qos(hdr->frame_control))) 1193 return; 1194 1195 if (unlikely(skb->protocol == cpu_to_be16(ETH_P_PAE))) 1196 return; 1197 1198 tid = ieee80211_get_tid(hdr); 1199 if (likely(sta->ampdu_mlme.tid_tx[tid])) 1200 return; 1201 1202 ieee80211_start_tx_ba_session(pubsta, tid, 0); 1203 } 1204 1205 static void 1206 minstrel_ht_tx_status(void *priv, struct ieee80211_supported_band *sband, 1207 void *priv_sta, struct ieee80211_tx_status *st) 1208 { 1209 struct ieee80211_tx_info *info = st->info; 1210 struct minstrel_ht_sta *mi = priv_sta; 1211 struct ieee80211_tx_rate *ar = info->status.rates; 1212 struct minstrel_rate_stats *rate, *rate2; 1213 struct minstrel_priv *mp = priv; 1214 u32 update_interval = mp->update_interval; 1215 bool last, update = false; 1216 int i; 1217 1218 /* This packet was aggregated but doesn't carry status info */ 1219 if ((info->flags & IEEE80211_TX_CTL_AMPDU) && 1220 !(info->flags & IEEE80211_TX_STAT_AMPDU)) 1221 return; 1222 1223 if (!(info->flags & IEEE80211_TX_STAT_AMPDU)) { 1224 info->status.ampdu_ack_len = 1225 (info->flags & IEEE80211_TX_STAT_ACK ? 1 : 0); 1226 info->status.ampdu_len = 1; 1227 } 1228 1229 /* wraparound */ 1230 if (mi->total_packets >= ~0 - info->status.ampdu_len) { 1231 mi->total_packets = 0; 1232 mi->sample_packets = 0; 1233 } 1234 1235 mi->total_packets += info->status.ampdu_len; 1236 if (info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE) 1237 mi->sample_packets += info->status.ampdu_len; 1238 1239 mi->ampdu_packets++; 1240 mi->ampdu_len += info->status.ampdu_len; 1241 1242 last = !minstrel_ht_txstat_valid(mp, mi, &ar[0]); 1243 for (i = 0; !last; i++) { 1244 last = (i == IEEE80211_TX_MAX_RATES - 1) || 1245 !minstrel_ht_txstat_valid(mp, mi, &ar[i + 1]); 1246 1247 rate = minstrel_ht_get_stats(mp, mi, &ar[i]); 1248 if (last) 1249 rate->success += info->status.ampdu_ack_len; 1250 1251 rate->attempts += ar[i].count * info->status.ampdu_len; 1252 } 1253 1254 if (mp->hw->max_rates > 1) { 1255 /* 1256 * check for sudden death of spatial multiplexing, 1257 * downgrade to a lower number of streams if necessary. 1258 */ 1259 rate = minstrel_get_ratestats(mi, mi->max_tp_rate[0]); 1260 if (rate->attempts > 30 && 1261 rate->success < rate->attempts / 4) { 1262 minstrel_downgrade_rate(mi, &mi->max_tp_rate[0], true); 1263 update = true; 1264 } 1265 1266 rate2 = minstrel_get_ratestats(mi, mi->max_tp_rate[1]); 1267 if (rate2->attempts > 30 && 1268 rate2->success < rate2->attempts / 4) { 1269 minstrel_downgrade_rate(mi, &mi->max_tp_rate[1], false); 1270 update = true; 1271 } 1272 } 1273 1274 if (time_after(jiffies, mi->last_stats_update + update_interval)) { 1275 update = true; 1276 minstrel_ht_update_stats(mp, mi); 1277 } 1278 1279 if (update) 1280 minstrel_ht_update_rates(mp, mi); 1281 } 1282 1283 static void 1284 minstrel_calc_retransmit(struct minstrel_priv *mp, struct minstrel_ht_sta *mi, 1285 int index) 1286 { 1287 struct minstrel_rate_stats *mrs; 1288 unsigned int tx_time, tx_time_rtscts, tx_time_data; 1289 unsigned int cw = mp->cw_min; 1290 unsigned int ctime = 0; 1291 unsigned int t_slot = 9; /* FIXME */ 1292 unsigned int ampdu_len = minstrel_ht_avg_ampdu_len(mi); 1293 unsigned int overhead = 0, overhead_rtscts = 0; 1294 1295 mrs = minstrel_get_ratestats(mi, index); 1296 if (mrs->prob_avg < MINSTREL_FRAC(1, 10)) { 1297 mrs->retry_count = 1; 1298 mrs->retry_count_rtscts = 1; 1299 return; 1300 } 1301 1302 mrs->retry_count = 2; 1303 mrs->retry_count_rtscts = 2; 1304 mrs->retry_updated = true; 1305 1306 tx_time_data = minstrel_get_duration(index) * ampdu_len / 1000; 1307 1308 /* Contention time for first 2 tries */ 1309 ctime = (t_slot * cw) >> 1; 1310 cw = min((cw << 1) | 1, mp->cw_max); 1311 ctime += (t_slot * cw) >> 1; 1312 cw = min((cw << 1) | 1, mp->cw_max); 1313 1314 if (minstrel_ht_is_legacy_group(MI_RATE_GROUP(index))) { 1315 overhead = mi->overhead_legacy; 1316 overhead_rtscts = mi->overhead_legacy_rtscts; 1317 } else { 1318 overhead = mi->overhead; 1319 overhead_rtscts = mi->overhead_rtscts; 1320 } 1321 1322 /* Total TX time for data and Contention after first 2 tries */ 1323 tx_time = ctime + 2 * (overhead + tx_time_data); 1324 tx_time_rtscts = ctime + 2 * (overhead_rtscts + tx_time_data); 1325 1326 /* See how many more tries we can fit inside segment size */ 1327 do { 1328 /* Contention time for this try */ 1329 ctime = (t_slot * cw) >> 1; 1330 cw = min((cw << 1) | 1, mp->cw_max); 1331 1332 /* Total TX time after this try */ 1333 tx_time += ctime + overhead + tx_time_data; 1334 tx_time_rtscts += ctime + overhead_rtscts + tx_time_data; 1335 1336 if (tx_time_rtscts < mp->segment_size) 1337 mrs->retry_count_rtscts++; 1338 } while ((tx_time < mp->segment_size) && 1339 (++mrs->retry_count < mp->max_retry)); 1340 } 1341 1342 1343 static void 1344 minstrel_ht_set_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi, 1345 struct ieee80211_sta_rates *ratetbl, int offset, int index) 1346 { 1347 int group_idx = MI_RATE_GROUP(index); 1348 const struct mcs_group *group = &minstrel_mcs_groups[group_idx]; 1349 struct minstrel_rate_stats *mrs; 1350 u8 idx; 1351 u16 flags = group->flags; 1352 1353 mrs = minstrel_get_ratestats(mi, index); 1354 if (!mrs->retry_updated) 1355 minstrel_calc_retransmit(mp, mi, index); 1356 1357 if (mrs->prob_avg < MINSTREL_FRAC(20, 100) || !mrs->retry_count) { 1358 ratetbl->rate[offset].count = 2; 1359 ratetbl->rate[offset].count_rts = 2; 1360 ratetbl->rate[offset].count_cts = 2; 1361 } else { 1362 ratetbl->rate[offset].count = mrs->retry_count; 1363 ratetbl->rate[offset].count_cts = mrs->retry_count; 1364 ratetbl->rate[offset].count_rts = mrs->retry_count_rtscts; 1365 } 1366 1367 index = MI_RATE_IDX(index); 1368 if (group_idx == MINSTREL_CCK_GROUP) 1369 idx = mp->cck_rates[index % ARRAY_SIZE(mp->cck_rates)]; 1370 else if (group_idx == MINSTREL_OFDM_GROUP) 1371 idx = mp->ofdm_rates[mi->band][index % 1372 ARRAY_SIZE(mp->ofdm_rates[0])]; 1373 else if (flags & IEEE80211_TX_RC_VHT_MCS) 1374 idx = ((group->streams - 1) << 4) | 1375 (index & 0xF); 1376 else 1377 idx = index + (group->streams - 1) * 8; 1378 1379 /* enable RTS/CTS if needed: 1380 * - if station is in dynamic SMPS (and streams > 1) 1381 * - for fallback rates, to increase chances of getting through 1382 */ 1383 if (offset > 0 || 1384 (mi->sta->smps_mode == IEEE80211_SMPS_DYNAMIC && 1385 group->streams > 1)) { 1386 ratetbl->rate[offset].count = ratetbl->rate[offset].count_rts; 1387 flags |= IEEE80211_TX_RC_USE_RTS_CTS; 1388 } 1389 1390 ratetbl->rate[offset].idx = idx; 1391 ratetbl->rate[offset].flags = flags; 1392 } 1393 1394 static inline int 1395 minstrel_ht_get_prob_avg(struct minstrel_ht_sta *mi, int rate) 1396 { 1397 int group = MI_RATE_GROUP(rate); 1398 rate = MI_RATE_IDX(rate); 1399 return mi->groups[group].rates[rate].prob_avg; 1400 } 1401 1402 static int 1403 minstrel_ht_get_max_amsdu_len(struct minstrel_ht_sta *mi) 1404 { 1405 int group = MI_RATE_GROUP(mi->max_prob_rate); 1406 const struct mcs_group *g = &minstrel_mcs_groups[group]; 1407 int rate = MI_RATE_IDX(mi->max_prob_rate); 1408 unsigned int duration; 1409 1410 /* Disable A-MSDU if max_prob_rate is bad */ 1411 if (mi->groups[group].rates[rate].prob_avg < MINSTREL_FRAC(50, 100)) 1412 return 1; 1413 1414 duration = g->duration[rate]; 1415 duration <<= g->shift; 1416 1417 /* If the rate is slower than single-stream MCS1, make A-MSDU limit small */ 1418 if (duration > MCS_DURATION(1, 0, 52)) 1419 return 500; 1420 1421 /* 1422 * If the rate is slower than single-stream MCS4, limit A-MSDU to usual 1423 * data packet size 1424 */ 1425 if (duration > MCS_DURATION(1, 0, 104)) 1426 return 1600; 1427 1428 /* 1429 * If the rate is slower than single-stream MCS7, or if the max throughput 1430 * rate success probability is less than 75%, limit A-MSDU to twice the usual 1431 * data packet size 1432 */ 1433 if (duration > MCS_DURATION(1, 0, 260) || 1434 (minstrel_ht_get_prob_avg(mi, mi->max_tp_rate[0]) < 1435 MINSTREL_FRAC(75, 100))) 1436 return 3200; 1437 1438 /* 1439 * HT A-MPDU limits maximum MPDU size under BA agreement to 4095 bytes. 1440 * Since aggregation sessions are started/stopped without txq flush, use 1441 * the limit here to avoid the complexity of having to de-aggregate 1442 * packets in the queue. 1443 */ 1444 if (!mi->sta->vht_cap.vht_supported) 1445 return IEEE80211_MAX_MPDU_LEN_HT_BA; 1446 1447 /* unlimited */ 1448 return 0; 1449 } 1450 1451 static void 1452 minstrel_ht_update_rates(struct minstrel_priv *mp, struct minstrel_ht_sta *mi) 1453 { 1454 struct ieee80211_sta_rates *rates; 1455 int i = 0; 1456 1457 rates = kzalloc(sizeof(*rates), GFP_ATOMIC); 1458 if (!rates) 1459 return; 1460 1461 /* Start with max_tp_rate[0] */ 1462 minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_tp_rate[0]); 1463 1464 if (mp->hw->max_rates >= 3) { 1465 /* At least 3 tx rates supported, use max_tp_rate[1] next */ 1466 minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_tp_rate[1]); 1467 } 1468 1469 if (mp->hw->max_rates >= 2) { 1470 minstrel_ht_set_rate(mp, mi, rates, i++, mi->max_prob_rate); 1471 } 1472 1473 mi->sta->max_rc_amsdu_len = minstrel_ht_get_max_amsdu_len(mi); 1474 rates->rate[i].idx = -1; 1475 rate_control_set_rates(mp->hw, mi->sta, rates); 1476 } 1477 1478 static u16 1479 minstrel_ht_get_sample_rate(struct minstrel_priv *mp, struct minstrel_ht_sta *mi) 1480 { 1481 u8 seq; 1482 1483 if (mp->hw->max_rates > 1) { 1484 seq = mi->sample_seq; 1485 mi->sample_seq = (seq + 1) % ARRAY_SIZE(minstrel_sample_seq); 1486 seq = minstrel_sample_seq[seq]; 1487 } else { 1488 seq = MINSTREL_SAMPLE_TYPE_INC; 1489 } 1490 1491 return __minstrel_ht_get_sample_rate(mi, seq); 1492 } 1493 1494 static void 1495 minstrel_ht_get_rate(void *priv, struct ieee80211_sta *sta, void *priv_sta, 1496 struct ieee80211_tx_rate_control *txrc) 1497 { 1498 const struct mcs_group *sample_group; 1499 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb); 1500 struct ieee80211_tx_rate *rate = &info->status.rates[0]; 1501 struct minstrel_ht_sta *mi = priv_sta; 1502 struct minstrel_priv *mp = priv; 1503 u16 sample_idx; 1504 1505 if (!(info->flags & IEEE80211_TX_CTL_AMPDU) && 1506 !minstrel_ht_is_legacy_group(MI_RATE_GROUP(mi->max_prob_rate))) 1507 minstrel_aggr_check(sta, txrc->skb); 1508 1509 info->flags |= mi->tx_flags; 1510 1511 #ifdef CONFIG_MAC80211_DEBUGFS 1512 if (mp->fixed_rate_idx != -1) 1513 return; 1514 #endif 1515 1516 /* Don't use EAPOL frames for sampling on non-mrr hw */ 1517 if (mp->hw->max_rates == 1 && 1518 (info->control.flags & IEEE80211_TX_CTRL_PORT_CTRL_PROTO)) 1519 return; 1520 1521 if (time_is_before_jiffies(mi->sample_time)) 1522 return; 1523 1524 mi->sample_time = jiffies + MINSTREL_SAMPLE_INTERVAL; 1525 sample_idx = minstrel_ht_get_sample_rate(mp, mi); 1526 if (!sample_idx) 1527 return; 1528 1529 sample_group = &minstrel_mcs_groups[MI_RATE_GROUP(sample_idx)]; 1530 sample_idx = MI_RATE_IDX(sample_idx); 1531 1532 if (sample_group == &minstrel_mcs_groups[MINSTREL_CCK_GROUP] && 1533 (sample_idx >= 4) != txrc->short_preamble) 1534 return; 1535 1536 info->flags |= IEEE80211_TX_CTL_RATE_CTRL_PROBE; 1537 rate->count = 1; 1538 1539 if (sample_group == &minstrel_mcs_groups[MINSTREL_CCK_GROUP]) { 1540 int idx = sample_idx % ARRAY_SIZE(mp->cck_rates); 1541 rate->idx = mp->cck_rates[idx]; 1542 } else if (sample_group == &minstrel_mcs_groups[MINSTREL_OFDM_GROUP]) { 1543 int idx = sample_idx % ARRAY_SIZE(mp->ofdm_rates[0]); 1544 rate->idx = mp->ofdm_rates[mi->band][idx]; 1545 } else if (sample_group->flags & IEEE80211_TX_RC_VHT_MCS) { 1546 ieee80211_rate_set_vht(rate, MI_RATE_IDX(sample_idx), 1547 sample_group->streams); 1548 } else { 1549 rate->idx = sample_idx + (sample_group->streams - 1) * 8; 1550 } 1551 1552 rate->flags = sample_group->flags; 1553 } 1554 1555 static void 1556 minstrel_ht_update_cck(struct minstrel_priv *mp, struct minstrel_ht_sta *mi, 1557 struct ieee80211_supported_band *sband, 1558 struct ieee80211_sta *sta) 1559 { 1560 int i; 1561 1562 if (sband->band != NL80211_BAND_2GHZ) 1563 return; 1564 1565 if (sta->ht_cap.ht_supported && 1566 !ieee80211_hw_check(mp->hw, SUPPORTS_HT_CCK_RATES)) 1567 return; 1568 1569 for (i = 0; i < 4; i++) { 1570 if (mp->cck_rates[i] == 0xff || 1571 !rate_supported(sta, sband->band, mp->cck_rates[i])) 1572 continue; 1573 1574 mi->supported[MINSTREL_CCK_GROUP] |= BIT(i); 1575 if (sband->bitrates[i].flags & IEEE80211_RATE_SHORT_PREAMBLE) 1576 mi->supported[MINSTREL_CCK_GROUP] |= BIT(i + 4); 1577 } 1578 } 1579 1580 static void 1581 minstrel_ht_update_ofdm(struct minstrel_priv *mp, struct minstrel_ht_sta *mi, 1582 struct ieee80211_supported_band *sband, 1583 struct ieee80211_sta *sta) 1584 { 1585 const u8 *rates; 1586 int i; 1587 1588 if (sta->ht_cap.ht_supported) 1589 return; 1590 1591 rates = mp->ofdm_rates[sband->band]; 1592 for (i = 0; i < ARRAY_SIZE(mp->ofdm_rates[0]); i++) { 1593 if (rates[i] == 0xff || 1594 !rate_supported(sta, sband->band, rates[i])) 1595 continue; 1596 1597 mi->supported[MINSTREL_OFDM_GROUP] |= BIT(i); 1598 } 1599 } 1600 1601 static void 1602 minstrel_ht_update_caps(void *priv, struct ieee80211_supported_band *sband, 1603 struct cfg80211_chan_def *chandef, 1604 struct ieee80211_sta *sta, void *priv_sta) 1605 { 1606 struct minstrel_priv *mp = priv; 1607 struct minstrel_ht_sta *mi = priv_sta; 1608 struct ieee80211_mcs_info *mcs = &sta->ht_cap.mcs; 1609 u16 ht_cap = sta->ht_cap.cap; 1610 struct ieee80211_sta_vht_cap *vht_cap = &sta->vht_cap; 1611 const struct ieee80211_rate *ctl_rate; 1612 bool ldpc, erp; 1613 int use_vht; 1614 int n_supported = 0; 1615 int ack_dur; 1616 int stbc; 1617 int i; 1618 1619 BUILD_BUG_ON(ARRAY_SIZE(minstrel_mcs_groups) != MINSTREL_GROUPS_NB); 1620 1621 if (vht_cap->vht_supported) 1622 use_vht = vht_cap->vht_mcs.tx_mcs_map != cpu_to_le16(~0); 1623 else 1624 use_vht = 0; 1625 1626 memset(mi, 0, sizeof(*mi)); 1627 1628 mi->sta = sta; 1629 mi->band = sband->band; 1630 mi->last_stats_update = jiffies; 1631 1632 ack_dur = ieee80211_frame_duration(sband->band, 10, 60, 1, 1, 0); 1633 mi->overhead = ieee80211_frame_duration(sband->band, 0, 60, 1, 1, 0); 1634 mi->overhead += ack_dur; 1635 mi->overhead_rtscts = mi->overhead + 2 * ack_dur; 1636 1637 ctl_rate = &sband->bitrates[rate_lowest_index(sband, sta)]; 1638 erp = ctl_rate->flags & IEEE80211_RATE_ERP_G; 1639 ack_dur = ieee80211_frame_duration(sband->band, 10, 1640 ctl_rate->bitrate, erp, 1, 1641 ieee80211_chandef_get_shift(chandef)); 1642 mi->overhead_legacy = ack_dur; 1643 mi->overhead_legacy_rtscts = mi->overhead_legacy + 2 * ack_dur; 1644 1645 mi->avg_ampdu_len = MINSTREL_FRAC(1, 1); 1646 1647 if (!use_vht) { 1648 stbc = (ht_cap & IEEE80211_HT_CAP_RX_STBC) >> 1649 IEEE80211_HT_CAP_RX_STBC_SHIFT; 1650 1651 ldpc = ht_cap & IEEE80211_HT_CAP_LDPC_CODING; 1652 } else { 1653 stbc = (vht_cap->cap & IEEE80211_VHT_CAP_RXSTBC_MASK) >> 1654 IEEE80211_VHT_CAP_RXSTBC_SHIFT; 1655 1656 ldpc = vht_cap->cap & IEEE80211_VHT_CAP_RXLDPC; 1657 } 1658 1659 mi->tx_flags |= stbc << IEEE80211_TX_CTL_STBC_SHIFT; 1660 if (ldpc) 1661 mi->tx_flags |= IEEE80211_TX_CTL_LDPC; 1662 1663 for (i = 0; i < ARRAY_SIZE(mi->groups); i++) { 1664 u32 gflags = minstrel_mcs_groups[i].flags; 1665 int bw, nss; 1666 1667 mi->supported[i] = 0; 1668 if (minstrel_ht_is_legacy_group(i)) 1669 continue; 1670 1671 if (gflags & IEEE80211_TX_RC_SHORT_GI) { 1672 if (gflags & IEEE80211_TX_RC_40_MHZ_WIDTH) { 1673 if (!(ht_cap & IEEE80211_HT_CAP_SGI_40)) 1674 continue; 1675 } else { 1676 if (!(ht_cap & IEEE80211_HT_CAP_SGI_20)) 1677 continue; 1678 } 1679 } 1680 1681 if (gflags & IEEE80211_TX_RC_40_MHZ_WIDTH && 1682 sta->bandwidth < IEEE80211_STA_RX_BW_40) 1683 continue; 1684 1685 nss = minstrel_mcs_groups[i].streams; 1686 1687 /* Mark MCS > 7 as unsupported if STA is in static SMPS mode */ 1688 if (sta->smps_mode == IEEE80211_SMPS_STATIC && nss > 1) 1689 continue; 1690 1691 /* HT rate */ 1692 if (gflags & IEEE80211_TX_RC_MCS) { 1693 if (use_vht && minstrel_vht_only) 1694 continue; 1695 1696 mi->supported[i] = mcs->rx_mask[nss - 1]; 1697 if (mi->supported[i]) 1698 n_supported++; 1699 continue; 1700 } 1701 1702 /* VHT rate */ 1703 if (!vht_cap->vht_supported || 1704 WARN_ON(!(gflags & IEEE80211_TX_RC_VHT_MCS)) || 1705 WARN_ON(gflags & IEEE80211_TX_RC_160_MHZ_WIDTH)) 1706 continue; 1707 1708 if (gflags & IEEE80211_TX_RC_80_MHZ_WIDTH) { 1709 if (sta->bandwidth < IEEE80211_STA_RX_BW_80 || 1710 ((gflags & IEEE80211_TX_RC_SHORT_GI) && 1711 !(vht_cap->cap & IEEE80211_VHT_CAP_SHORT_GI_80))) { 1712 continue; 1713 } 1714 } 1715 1716 if (gflags & IEEE80211_TX_RC_40_MHZ_WIDTH) 1717 bw = BW_40; 1718 else if (gflags & IEEE80211_TX_RC_80_MHZ_WIDTH) 1719 bw = BW_80; 1720 else 1721 bw = BW_20; 1722 1723 mi->supported[i] = minstrel_get_valid_vht_rates(bw, nss, 1724 vht_cap->vht_mcs.tx_mcs_map); 1725 1726 if (mi->supported[i]) 1727 n_supported++; 1728 } 1729 1730 minstrel_ht_update_cck(mp, mi, sband, sta); 1731 minstrel_ht_update_ofdm(mp, mi, sband, sta); 1732 1733 /* create an initial rate table with the lowest supported rates */ 1734 minstrel_ht_update_stats(mp, mi); 1735 minstrel_ht_update_rates(mp, mi); 1736 } 1737 1738 static void 1739 minstrel_ht_rate_init(void *priv, struct ieee80211_supported_band *sband, 1740 struct cfg80211_chan_def *chandef, 1741 struct ieee80211_sta *sta, void *priv_sta) 1742 { 1743 minstrel_ht_update_caps(priv, sband, chandef, sta, priv_sta); 1744 } 1745 1746 static void 1747 minstrel_ht_rate_update(void *priv, struct ieee80211_supported_band *sband, 1748 struct cfg80211_chan_def *chandef, 1749 struct ieee80211_sta *sta, void *priv_sta, 1750 u32 changed) 1751 { 1752 minstrel_ht_update_caps(priv, sband, chandef, sta, priv_sta); 1753 } 1754 1755 static void * 1756 minstrel_ht_alloc_sta(void *priv, struct ieee80211_sta *sta, gfp_t gfp) 1757 { 1758 struct ieee80211_supported_band *sband; 1759 struct minstrel_ht_sta *mi; 1760 struct minstrel_priv *mp = priv; 1761 struct ieee80211_hw *hw = mp->hw; 1762 int max_rates = 0; 1763 int i; 1764 1765 for (i = 0; i < NUM_NL80211_BANDS; i++) { 1766 sband = hw->wiphy->bands[i]; 1767 if (sband && sband->n_bitrates > max_rates) 1768 max_rates = sband->n_bitrates; 1769 } 1770 1771 return kzalloc(sizeof(*mi), gfp); 1772 } 1773 1774 static void 1775 minstrel_ht_free_sta(void *priv, struct ieee80211_sta *sta, void *priv_sta) 1776 { 1777 kfree(priv_sta); 1778 } 1779 1780 static void 1781 minstrel_ht_fill_rate_array(u8 *dest, struct ieee80211_supported_band *sband, 1782 const s16 *bitrates, int n_rates, u32 rate_flags) 1783 { 1784 int i, j; 1785 1786 for (i = 0; i < sband->n_bitrates; i++) { 1787 struct ieee80211_rate *rate = &sband->bitrates[i]; 1788 1789 if ((rate_flags & sband->bitrates[i].flags) != rate_flags) 1790 continue; 1791 1792 for (j = 0; j < n_rates; j++) { 1793 if (rate->bitrate != bitrates[j]) 1794 continue; 1795 1796 dest[j] = i; 1797 break; 1798 } 1799 } 1800 } 1801 1802 static void 1803 minstrel_ht_init_cck_rates(struct minstrel_priv *mp) 1804 { 1805 static const s16 bitrates[4] = { 10, 20, 55, 110 }; 1806 struct ieee80211_supported_band *sband; 1807 u32 rate_flags = ieee80211_chandef_rate_flags(&mp->hw->conf.chandef); 1808 1809 memset(mp->cck_rates, 0xff, sizeof(mp->cck_rates)); 1810 sband = mp->hw->wiphy->bands[NL80211_BAND_2GHZ]; 1811 if (!sband) 1812 return; 1813 1814 BUILD_BUG_ON(ARRAY_SIZE(mp->cck_rates) != ARRAY_SIZE(bitrates)); 1815 minstrel_ht_fill_rate_array(mp->cck_rates, sband, 1816 minstrel_cck_bitrates, 1817 ARRAY_SIZE(minstrel_cck_bitrates), 1818 rate_flags); 1819 } 1820 1821 static void 1822 minstrel_ht_init_ofdm_rates(struct minstrel_priv *mp, enum nl80211_band band) 1823 { 1824 static const s16 bitrates[8] = { 60, 90, 120, 180, 240, 360, 480, 540 }; 1825 struct ieee80211_supported_band *sband; 1826 u32 rate_flags = ieee80211_chandef_rate_flags(&mp->hw->conf.chandef); 1827 1828 memset(mp->ofdm_rates[band], 0xff, sizeof(mp->ofdm_rates[band])); 1829 sband = mp->hw->wiphy->bands[band]; 1830 if (!sband) 1831 return; 1832 1833 BUILD_BUG_ON(ARRAY_SIZE(mp->ofdm_rates[band]) != ARRAY_SIZE(bitrates)); 1834 minstrel_ht_fill_rate_array(mp->ofdm_rates[band], sband, 1835 minstrel_ofdm_bitrates, 1836 ARRAY_SIZE(minstrel_ofdm_bitrates), 1837 rate_flags); 1838 } 1839 1840 static void * 1841 minstrel_ht_alloc(struct ieee80211_hw *hw) 1842 { 1843 struct minstrel_priv *mp; 1844 int i; 1845 1846 mp = kzalloc(sizeof(struct minstrel_priv), GFP_ATOMIC); 1847 if (!mp) 1848 return NULL; 1849 1850 /* contention window settings 1851 * Just an approximation. Using the per-queue values would complicate 1852 * the calculations and is probably unnecessary */ 1853 mp->cw_min = 15; 1854 mp->cw_max = 1023; 1855 1856 /* maximum time that the hw is allowed to stay in one MRR segment */ 1857 mp->segment_size = 6000; 1858 1859 if (hw->max_rate_tries > 0) 1860 mp->max_retry = hw->max_rate_tries; 1861 else 1862 /* safe default, does not necessarily have to match hw properties */ 1863 mp->max_retry = 7; 1864 1865 if (hw->max_rates >= 4) 1866 mp->has_mrr = true; 1867 1868 mp->hw = hw; 1869 mp->update_interval = HZ / 20; 1870 1871 minstrel_ht_init_cck_rates(mp); 1872 for (i = 0; i < ARRAY_SIZE(mp->hw->wiphy->bands); i++) 1873 minstrel_ht_init_ofdm_rates(mp, i); 1874 1875 return mp; 1876 } 1877 1878 #ifdef CONFIG_MAC80211_DEBUGFS 1879 static void minstrel_ht_add_debugfs(struct ieee80211_hw *hw, void *priv, 1880 struct dentry *debugfsdir) 1881 { 1882 struct minstrel_priv *mp = priv; 1883 1884 mp->fixed_rate_idx = (u32) -1; 1885 debugfs_create_u32("fixed_rate_idx", S_IRUGO | S_IWUGO, debugfsdir, 1886 &mp->fixed_rate_idx); 1887 } 1888 #endif 1889 1890 static void 1891 minstrel_ht_free(void *priv) 1892 { 1893 kfree(priv); 1894 } 1895 1896 static u32 minstrel_ht_get_expected_throughput(void *priv_sta) 1897 { 1898 struct minstrel_ht_sta *mi = priv_sta; 1899 int i, j, prob, tp_avg; 1900 1901 i = MI_RATE_GROUP(mi->max_tp_rate[0]); 1902 j = MI_RATE_IDX(mi->max_tp_rate[0]); 1903 prob = mi->groups[i].rates[j].prob_avg; 1904 1905 /* convert tp_avg from pkt per second in kbps */ 1906 tp_avg = minstrel_ht_get_tp_avg(mi, i, j, prob) * 10; 1907 tp_avg = tp_avg * AVG_PKT_SIZE * 8 / 1024; 1908 1909 return tp_avg; 1910 } 1911 1912 static const struct rate_control_ops mac80211_minstrel_ht = { 1913 .name = "minstrel_ht", 1914 .tx_status_ext = minstrel_ht_tx_status, 1915 .get_rate = minstrel_ht_get_rate, 1916 .rate_init = minstrel_ht_rate_init, 1917 .rate_update = minstrel_ht_rate_update, 1918 .alloc_sta = minstrel_ht_alloc_sta, 1919 .free_sta = minstrel_ht_free_sta, 1920 .alloc = minstrel_ht_alloc, 1921 .free = minstrel_ht_free, 1922 #ifdef CONFIG_MAC80211_DEBUGFS 1923 .add_debugfs = minstrel_ht_add_debugfs, 1924 .add_sta_debugfs = minstrel_ht_add_sta_debugfs, 1925 #endif 1926 .get_expected_throughput = minstrel_ht_get_expected_throughput, 1927 }; 1928 1929 1930 static void __init init_sample_table(void) 1931 { 1932 int col, i, new_idx; 1933 u8 rnd[MCS_GROUP_RATES]; 1934 1935 memset(sample_table, 0xff, sizeof(sample_table)); 1936 for (col = 0; col < SAMPLE_COLUMNS; col++) { 1937 prandom_bytes(rnd, sizeof(rnd)); 1938 for (i = 0; i < MCS_GROUP_RATES; i++) { 1939 new_idx = (i + rnd[i]) % MCS_GROUP_RATES; 1940 while (sample_table[col][new_idx] != 0xff) 1941 new_idx = (new_idx + 1) % MCS_GROUP_RATES; 1942 1943 sample_table[col][new_idx] = i; 1944 } 1945 } 1946 } 1947 1948 int __init 1949 rc80211_minstrel_init(void) 1950 { 1951 init_sample_table(); 1952 return ieee80211_rate_control_register(&mac80211_minstrel_ht); 1953 } 1954 1955 void 1956 rc80211_minstrel_exit(void) 1957 { 1958 ieee80211_rate_control_unregister(&mac80211_minstrel_ht); 1959 } 1960