1 // SPDX-License-Identifier: GPL-2.0-only 2 /****************************************************************************** 3 * 4 * Copyright(c) 2005 - 2011 Intel Corporation. All rights reserved. 5 * 6 * Contact Information: 7 * Intel Linux Wireless <ilw@linux.intel.com> 8 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497 9 * 10 *****************************************************************************/ 11 12 #include <linux/kernel.h> 13 #include <linux/skbuff.h> 14 #include <linux/slab.h> 15 #include <net/mac80211.h> 16 17 #include <linux/netdevice.h> 18 #include <linux/etherdevice.h> 19 #include <linux/delay.h> 20 21 #include <linux/workqueue.h> 22 23 #include "commands.h" 24 #include "3945.h" 25 26 #define RS_NAME "iwl-3945-rs" 27 28 static s32 il3945_expected_tpt_g[RATE_COUNT_3945] = { 29 7, 13, 35, 58, 0, 0, 76, 104, 130, 168, 191, 202 30 }; 31 32 static s32 il3945_expected_tpt_g_prot[RATE_COUNT_3945] = { 33 7, 13, 35, 58, 0, 0, 0, 80, 93, 113, 123, 125 34 }; 35 36 static s32 il3945_expected_tpt_a[RATE_COUNT_3945] = { 37 0, 0, 0, 0, 40, 57, 72, 98, 121, 154, 177, 186 38 }; 39 40 static s32 il3945_expected_tpt_b[RATE_COUNT_3945] = { 41 7, 13, 35, 58, 0, 0, 0, 0, 0, 0, 0, 0 42 }; 43 44 struct il3945_tpt_entry { 45 s8 min_rssi; 46 u8 idx; 47 }; 48 49 static struct il3945_tpt_entry il3945_tpt_table_a[] = { 50 {-60, RATE_54M_IDX}, 51 {-64, RATE_48M_IDX}, 52 {-72, RATE_36M_IDX}, 53 {-80, RATE_24M_IDX}, 54 {-84, RATE_18M_IDX}, 55 {-85, RATE_12M_IDX}, 56 {-87, RATE_9M_IDX}, 57 {-89, RATE_6M_IDX} 58 }; 59 60 static struct il3945_tpt_entry il3945_tpt_table_g[] = { 61 {-60, RATE_54M_IDX}, 62 {-64, RATE_48M_IDX}, 63 {-68, RATE_36M_IDX}, 64 {-80, RATE_24M_IDX}, 65 {-84, RATE_18M_IDX}, 66 {-85, RATE_12M_IDX}, 67 {-86, RATE_11M_IDX}, 68 {-88, RATE_5M_IDX}, 69 {-90, RATE_2M_IDX}, 70 {-92, RATE_1M_IDX} 71 }; 72 73 #define RATE_MAX_WINDOW 62 74 #define RATE_FLUSH (3*HZ) 75 #define RATE_WIN_FLUSH (HZ/2) 76 #define IL39_RATE_HIGH_TH 11520 77 #define IL_SUCCESS_UP_TH 8960 78 #define IL_SUCCESS_DOWN_TH 10880 79 #define RATE_MIN_FAILURE_TH 6 80 #define RATE_MIN_SUCCESS_TH 8 81 #define RATE_DECREASE_TH 1920 82 #define RATE_RETRY_TH 15 83 84 static u8 85 il3945_get_rate_idx_by_rssi(s32 rssi, enum nl80211_band band) 86 { 87 u32 idx = 0; 88 u32 table_size = 0; 89 struct il3945_tpt_entry *tpt_table = NULL; 90 91 if (rssi < IL_MIN_RSSI_VAL || rssi > IL_MAX_RSSI_VAL) 92 rssi = IL_MIN_RSSI_VAL; 93 94 switch (band) { 95 case NL80211_BAND_2GHZ: 96 tpt_table = il3945_tpt_table_g; 97 table_size = ARRAY_SIZE(il3945_tpt_table_g); 98 break; 99 case NL80211_BAND_5GHZ: 100 tpt_table = il3945_tpt_table_a; 101 table_size = ARRAY_SIZE(il3945_tpt_table_a); 102 break; 103 default: 104 BUG(); 105 break; 106 } 107 108 while (idx < table_size && rssi < tpt_table[idx].min_rssi) 109 idx++; 110 111 idx = min(idx, table_size - 1); 112 113 return tpt_table[idx].idx; 114 } 115 116 static void 117 il3945_clear_win(struct il3945_rate_scale_data *win) 118 { 119 win->data = 0; 120 win->success_counter = 0; 121 win->success_ratio = -1; 122 win->counter = 0; 123 win->average_tpt = IL_INVALID_VALUE; 124 win->stamp = 0; 125 } 126 127 /** 128 * il3945_rate_scale_flush_wins - flush out the rate scale wins 129 * 130 * Returns the number of wins that have gathered data but were 131 * not flushed. If there were any that were not flushed, then 132 * reschedule the rate flushing routine. 133 */ 134 static int 135 il3945_rate_scale_flush_wins(struct il3945_rs_sta *rs_sta) 136 { 137 int unflushed = 0; 138 int i; 139 unsigned long flags; 140 struct il_priv *il __maybe_unused = rs_sta->il; 141 142 /* 143 * For each rate, if we have collected data on that rate 144 * and it has been more than RATE_WIN_FLUSH 145 * since we flushed, clear out the gathered stats 146 */ 147 for (i = 0; i < RATE_COUNT_3945; i++) { 148 if (!rs_sta->win[i].counter) 149 continue; 150 151 spin_lock_irqsave(&rs_sta->lock, flags); 152 if (time_after(jiffies, rs_sta->win[i].stamp + RATE_WIN_FLUSH)) { 153 D_RATE("flushing %d samples of rate " "idx %d\n", 154 rs_sta->win[i].counter, i); 155 il3945_clear_win(&rs_sta->win[i]); 156 } else 157 unflushed++; 158 spin_unlock_irqrestore(&rs_sta->lock, flags); 159 } 160 161 return unflushed; 162 } 163 164 #define RATE_FLUSH_MAX 5000 /* msec */ 165 #define RATE_FLUSH_MIN 50 /* msec */ 166 #define IL_AVERAGE_PACKETS 1500 167 168 static void 169 il3945_bg_rate_scale_flush(struct timer_list *t) 170 { 171 struct il3945_rs_sta *rs_sta = from_timer(rs_sta, t, rate_scale_flush); 172 struct il_priv *il __maybe_unused = rs_sta->il; 173 int unflushed = 0; 174 unsigned long flags; 175 u32 packet_count, duration, pps; 176 177 D_RATE("enter\n"); 178 179 unflushed = il3945_rate_scale_flush_wins(rs_sta); 180 181 spin_lock_irqsave(&rs_sta->lock, flags); 182 183 /* Number of packets Rx'd since last time this timer ran */ 184 packet_count = (rs_sta->tx_packets - rs_sta->last_tx_packets) + 1; 185 186 rs_sta->last_tx_packets = rs_sta->tx_packets + 1; 187 188 if (unflushed) { 189 duration = 190 jiffies_to_msecs(jiffies - rs_sta->last_partial_flush); 191 192 D_RATE("Tx'd %d packets in %dms\n", packet_count, duration); 193 194 /* Determine packets per second */ 195 if (duration) 196 pps = (packet_count * 1000) / duration; 197 else 198 pps = 0; 199 200 if (pps) { 201 duration = (IL_AVERAGE_PACKETS * 1000) / pps; 202 if (duration < RATE_FLUSH_MIN) 203 duration = RATE_FLUSH_MIN; 204 else if (duration > RATE_FLUSH_MAX) 205 duration = RATE_FLUSH_MAX; 206 } else 207 duration = RATE_FLUSH_MAX; 208 209 rs_sta->flush_time = msecs_to_jiffies(duration); 210 211 D_RATE("new flush period: %d msec ave %d\n", duration, 212 packet_count); 213 214 mod_timer(&rs_sta->rate_scale_flush, 215 jiffies + rs_sta->flush_time); 216 217 rs_sta->last_partial_flush = jiffies; 218 } else { 219 rs_sta->flush_time = RATE_FLUSH; 220 rs_sta->flush_pending = 0; 221 } 222 /* If there weren't any unflushed entries, we don't schedule the timer 223 * to run again */ 224 225 rs_sta->last_flush = jiffies; 226 227 spin_unlock_irqrestore(&rs_sta->lock, flags); 228 229 D_RATE("leave\n"); 230 } 231 232 /** 233 * il3945_collect_tx_data - Update the success/failure sliding win 234 * 235 * We keep a sliding win of the last 64 packets transmitted 236 * at this rate. win->data contains the bitmask of successful 237 * packets. 238 */ 239 static void 240 il3945_collect_tx_data(struct il3945_rs_sta *rs_sta, 241 struct il3945_rate_scale_data *win, int success, 242 int retries, int idx) 243 { 244 unsigned long flags; 245 s32 fail_count; 246 struct il_priv *il __maybe_unused = rs_sta->il; 247 248 if (!retries) { 249 D_RATE("leave: retries == 0 -- should be at least 1\n"); 250 return; 251 } 252 253 spin_lock_irqsave(&rs_sta->lock, flags); 254 255 /* 256 * Keep track of only the latest 62 tx frame attempts in this rate's 257 * history win; anything older isn't really relevant any more. 258 * If we have filled up the sliding win, drop the oldest attempt; 259 * if the oldest attempt (highest bit in bitmap) shows "success", 260 * subtract "1" from the success counter (this is the main reason 261 * we keep these bitmaps!). 262 * */ 263 while (retries > 0) { 264 if (win->counter >= RATE_MAX_WINDOW) { 265 266 /* remove earliest */ 267 win->counter = RATE_MAX_WINDOW - 1; 268 269 if (win->data & (1ULL << (RATE_MAX_WINDOW - 1))) { 270 win->data &= ~(1ULL << (RATE_MAX_WINDOW - 1)); 271 win->success_counter--; 272 } 273 } 274 275 /* Increment frames-attempted counter */ 276 win->counter++; 277 278 /* Shift bitmap by one frame (throw away oldest history), 279 * OR in "1", and increment "success" if this 280 * frame was successful. */ 281 win->data <<= 1; 282 if (success > 0) { 283 win->success_counter++; 284 win->data |= 0x1; 285 success--; 286 } 287 288 retries--; 289 } 290 291 /* Calculate current success ratio, avoid divide-by-0! */ 292 if (win->counter > 0) 293 win->success_ratio = 294 128 * (100 * win->success_counter) / win->counter; 295 else 296 win->success_ratio = IL_INVALID_VALUE; 297 298 fail_count = win->counter - win->success_counter; 299 300 /* Calculate average throughput, if we have enough history. */ 301 if (fail_count >= RATE_MIN_FAILURE_TH || 302 win->success_counter >= RATE_MIN_SUCCESS_TH) 303 win->average_tpt = 304 ((win->success_ratio * rs_sta->expected_tpt[idx] + 305 64) / 128); 306 else 307 win->average_tpt = IL_INVALID_VALUE; 308 309 /* Tag this win as having been updated */ 310 win->stamp = jiffies; 311 312 spin_unlock_irqrestore(&rs_sta->lock, flags); 313 } 314 315 /* 316 * Called after adding a new station to initialize rate scaling 317 */ 318 void 319 il3945_rs_rate_init(struct il_priv *il, struct ieee80211_sta *sta, u8 sta_id) 320 { 321 struct ieee80211_hw *hw = il->hw; 322 struct ieee80211_conf *conf = &il->hw->conf; 323 struct il3945_sta_priv *psta; 324 struct il3945_rs_sta *rs_sta; 325 struct ieee80211_supported_band *sband; 326 int i; 327 328 D_INFO("enter\n"); 329 if (sta_id == il->hw_params.bcast_id) 330 goto out; 331 332 psta = (struct il3945_sta_priv *)sta->drv_priv; 333 rs_sta = &psta->rs_sta; 334 sband = hw->wiphy->bands[conf->chandef.chan->band]; 335 336 rs_sta->il = il; 337 338 rs_sta->start_rate = RATE_INVALID; 339 340 /* default to just 802.11b */ 341 rs_sta->expected_tpt = il3945_expected_tpt_b; 342 343 rs_sta->last_partial_flush = jiffies; 344 rs_sta->last_flush = jiffies; 345 rs_sta->flush_time = RATE_FLUSH; 346 rs_sta->last_tx_packets = 0; 347 348 for (i = 0; i < RATE_COUNT_3945; i++) 349 il3945_clear_win(&rs_sta->win[i]); 350 351 /* TODO: what is a good starting rate for STA? About middle? Maybe not 352 * the lowest or the highest rate.. Could consider using RSSI from 353 * previous packets? Need to have IEEE 802.1X auth succeed immediately 354 * after assoc.. */ 355 356 for (i = sband->n_bitrates - 1; i >= 0; i--) { 357 if (sta->supp_rates[sband->band] & (1 << i)) { 358 rs_sta->last_txrate_idx = i; 359 break; 360 } 361 } 362 363 il->_3945.sta_supp_rates = sta->supp_rates[sband->band]; 364 /* For 5 GHz band it start at IL_FIRST_OFDM_RATE */ 365 if (sband->band == NL80211_BAND_5GHZ) { 366 rs_sta->last_txrate_idx += IL_FIRST_OFDM_RATE; 367 il->_3945.sta_supp_rates <<= IL_FIRST_OFDM_RATE; 368 } 369 370 out: 371 il->stations[sta_id].used &= ~IL_STA_UCODE_INPROGRESS; 372 373 D_INFO("leave\n"); 374 } 375 376 static void * 377 il3945_rs_alloc(struct ieee80211_hw *hw) 378 { 379 return hw->priv; 380 } 381 382 /* rate scale requires free function to be implemented */ 383 static void 384 il3945_rs_free(void *il) 385 { 386 } 387 388 static void * 389 il3945_rs_alloc_sta(void *il_priv, struct ieee80211_sta *sta, gfp_t gfp) 390 { 391 struct il3945_rs_sta *rs_sta; 392 struct il3945_sta_priv *psta = (void *)sta->drv_priv; 393 struct il_priv *il __maybe_unused = il_priv; 394 395 D_RATE("enter\n"); 396 397 rs_sta = &psta->rs_sta; 398 399 spin_lock_init(&rs_sta->lock); 400 timer_setup(&rs_sta->rate_scale_flush, il3945_bg_rate_scale_flush, 0); 401 D_RATE("leave\n"); 402 403 return rs_sta; 404 } 405 406 static void 407 il3945_rs_free_sta(void *il_priv, struct ieee80211_sta *sta, void *il_sta) 408 { 409 struct il3945_rs_sta *rs_sta = il_sta; 410 411 /* 412 * Be careful not to use any members of il3945_rs_sta (like trying 413 * to use il_priv to print out debugging) since it may not be fully 414 * initialized at this point. 415 */ 416 del_timer_sync(&rs_sta->rate_scale_flush); 417 } 418 419 /** 420 * il3945_rs_tx_status - Update rate control values based on Tx results 421 * 422 * NOTE: Uses il_priv->retry_rate for the # of retries attempted by 423 * the hardware for each rate. 424 */ 425 static void 426 il3945_rs_tx_status(void *il_rate, struct ieee80211_supported_band *sband, 427 struct ieee80211_sta *sta, void *il_sta, 428 struct sk_buff *skb) 429 { 430 s8 retries = 0, current_count; 431 int scale_rate_idx, first_idx, last_idx; 432 unsigned long flags; 433 struct il_priv *il = (struct il_priv *)il_rate; 434 struct il3945_rs_sta *rs_sta = il_sta; 435 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 436 437 D_RATE("enter\n"); 438 439 retries = info->status.rates[0].count; 440 /* Sanity Check for retries */ 441 if (retries > RATE_RETRY_TH) 442 retries = RATE_RETRY_TH; 443 444 first_idx = sband->bitrates[info->status.rates[0].idx].hw_value; 445 if (first_idx < 0 || first_idx >= RATE_COUNT_3945) { 446 D_RATE("leave: Rate out of bounds: %d\n", first_idx); 447 return; 448 } 449 450 if (!il_sta) { 451 D_RATE("leave: No STA il data to update!\n"); 452 return; 453 } 454 455 /* Treat uninitialized rate scaling data same as non-existing. */ 456 if (!rs_sta->il) { 457 D_RATE("leave: STA il data uninitialized!\n"); 458 return; 459 } 460 461 rs_sta->tx_packets++; 462 463 scale_rate_idx = first_idx; 464 last_idx = first_idx; 465 466 /* 467 * Update the win for each rate. We determine which rates 468 * were Tx'd based on the total number of retries vs. the number 469 * of retries configured for each rate -- currently set to the 470 * il value 'retry_rate' vs. rate specific 471 * 472 * On exit from this while loop last_idx indicates the rate 473 * at which the frame was finally transmitted (or failed if no 474 * ACK) 475 */ 476 while (retries > 1) { 477 if ((retries - 1) < il->retry_rate) { 478 current_count = (retries - 1); 479 last_idx = scale_rate_idx; 480 } else { 481 current_count = il->retry_rate; 482 last_idx = il3945_rs_next_rate(il, scale_rate_idx); 483 } 484 485 /* Update this rate accounting for as many retries 486 * as was used for it (per current_count) */ 487 il3945_collect_tx_data(rs_sta, &rs_sta->win[scale_rate_idx], 0, 488 current_count, scale_rate_idx); 489 D_RATE("Update rate %d for %d retries.\n", scale_rate_idx, 490 current_count); 491 492 retries -= current_count; 493 494 scale_rate_idx = last_idx; 495 } 496 497 /* Update the last idx win with success/failure based on ACK */ 498 D_RATE("Update rate %d with %s.\n", last_idx, 499 (info->flags & IEEE80211_TX_STAT_ACK) ? "success" : "failure"); 500 il3945_collect_tx_data(rs_sta, &rs_sta->win[last_idx], 501 info->flags & IEEE80211_TX_STAT_ACK, 1, 502 last_idx); 503 504 /* We updated the rate scale win -- if its been more than 505 * flush_time since the last run, schedule the flush 506 * again */ 507 spin_lock_irqsave(&rs_sta->lock, flags); 508 509 if (!rs_sta->flush_pending && 510 time_after(jiffies, rs_sta->last_flush + rs_sta->flush_time)) { 511 512 rs_sta->last_partial_flush = jiffies; 513 rs_sta->flush_pending = 1; 514 mod_timer(&rs_sta->rate_scale_flush, 515 jiffies + rs_sta->flush_time); 516 } 517 518 spin_unlock_irqrestore(&rs_sta->lock, flags); 519 520 D_RATE("leave\n"); 521 } 522 523 static u16 524 il3945_get_adjacent_rate(struct il3945_rs_sta *rs_sta, u8 idx, u16 rate_mask, 525 enum nl80211_band band) 526 { 527 u8 high = RATE_INVALID; 528 u8 low = RATE_INVALID; 529 struct il_priv *il __maybe_unused = rs_sta->il; 530 531 /* 802.11A walks to the next literal adjacent rate in 532 * the rate table */ 533 if (unlikely(band == NL80211_BAND_5GHZ)) { 534 int i; 535 u32 mask; 536 537 /* Find the previous rate that is in the rate mask */ 538 i = idx - 1; 539 for (mask = (1 << i); i >= 0; i--, mask >>= 1) { 540 if (rate_mask & mask) { 541 low = i; 542 break; 543 } 544 } 545 546 /* Find the next rate that is in the rate mask */ 547 i = idx + 1; 548 for (mask = (1 << i); i < RATE_COUNT_3945; i++, mask <<= 1) { 549 if (rate_mask & mask) { 550 high = i; 551 break; 552 } 553 } 554 555 return (high << 8) | low; 556 } 557 558 low = idx; 559 while (low != RATE_INVALID) { 560 if (rs_sta->tgg) 561 low = il3945_rates[low].prev_rs_tgg; 562 else 563 low = il3945_rates[low].prev_rs; 564 if (low == RATE_INVALID) 565 break; 566 if (rate_mask & (1 << low)) 567 break; 568 D_RATE("Skipping masked lower rate: %d\n", low); 569 } 570 571 high = idx; 572 while (high != RATE_INVALID) { 573 if (rs_sta->tgg) 574 high = il3945_rates[high].next_rs_tgg; 575 else 576 high = il3945_rates[high].next_rs; 577 if (high == RATE_INVALID) 578 break; 579 if (rate_mask & (1 << high)) 580 break; 581 D_RATE("Skipping masked higher rate: %d\n", high); 582 } 583 584 return (high << 8) | low; 585 } 586 587 /** 588 * il3945_rs_get_rate - find the rate for the requested packet 589 * 590 * Returns the ieee80211_rate structure allocated by the driver. 591 * 592 * The rate control algorithm has no internal mapping between hw_mode's 593 * rate ordering and the rate ordering used by the rate control algorithm. 594 * 595 * The rate control algorithm uses a single table of rates that goes across 596 * the entire A/B/G spectrum vs. being limited to just one particular 597 * hw_mode. 598 * 599 * As such, we can't convert the idx obtained below into the hw_mode's 600 * rate table and must reference the driver allocated rate table 601 * 602 */ 603 static void 604 il3945_rs_get_rate(void *il_r, struct ieee80211_sta *sta, void *il_sta, 605 struct ieee80211_tx_rate_control *txrc) 606 { 607 struct ieee80211_supported_band *sband = txrc->sband; 608 struct sk_buff *skb = txrc->skb; 609 u8 low = RATE_INVALID; 610 u8 high = RATE_INVALID; 611 u16 high_low; 612 int idx; 613 struct il3945_rs_sta *rs_sta = il_sta; 614 struct il3945_rate_scale_data *win = NULL; 615 int current_tpt = IL_INVALID_VALUE; 616 int low_tpt = IL_INVALID_VALUE; 617 int high_tpt = IL_INVALID_VALUE; 618 u32 fail_count; 619 s8 scale_action = 0; 620 unsigned long flags; 621 u16 rate_mask; 622 s8 max_rate_idx = -1; 623 struct il_priv *il __maybe_unused = (struct il_priv *)il_r; 624 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 625 626 D_RATE("enter\n"); 627 628 /* Treat uninitialized rate scaling data same as non-existing. */ 629 if (rs_sta && !rs_sta->il) { 630 D_RATE("Rate scaling information not initialized yet.\n"); 631 il_sta = NULL; 632 } 633 634 rate_mask = sta->supp_rates[sband->band]; 635 636 /* get user max rate if set */ 637 max_rate_idx = fls(txrc->rate_idx_mask) - 1; 638 if (sband->band == NL80211_BAND_5GHZ && max_rate_idx != -1) 639 max_rate_idx += IL_FIRST_OFDM_RATE; 640 if (max_rate_idx < 0 || max_rate_idx >= RATE_COUNT) 641 max_rate_idx = -1; 642 643 idx = min(rs_sta->last_txrate_idx & 0xffff, RATE_COUNT_3945 - 1); 644 645 if (sband->band == NL80211_BAND_5GHZ) 646 rate_mask = rate_mask << IL_FIRST_OFDM_RATE; 647 648 spin_lock_irqsave(&rs_sta->lock, flags); 649 650 /* for recent assoc, choose best rate regarding 651 * to rssi value 652 */ 653 if (rs_sta->start_rate != RATE_INVALID) { 654 if (rs_sta->start_rate < idx && 655 (rate_mask & (1 << rs_sta->start_rate))) 656 idx = rs_sta->start_rate; 657 rs_sta->start_rate = RATE_INVALID; 658 } 659 660 /* force user max rate if set by user */ 661 if (max_rate_idx != -1 && max_rate_idx < idx) { 662 if (rate_mask & (1 << max_rate_idx)) 663 idx = max_rate_idx; 664 } 665 666 win = &(rs_sta->win[idx]); 667 668 fail_count = win->counter - win->success_counter; 669 670 if (fail_count < RATE_MIN_FAILURE_TH && 671 win->success_counter < RATE_MIN_SUCCESS_TH) { 672 spin_unlock_irqrestore(&rs_sta->lock, flags); 673 674 D_RATE("Invalid average_tpt on rate %d: " 675 "counter: %d, success_counter: %d, " 676 "expected_tpt is %sNULL\n", idx, win->counter, 677 win->success_counter, 678 rs_sta->expected_tpt ? "not " : ""); 679 680 /* Can't calculate this yet; not enough history */ 681 win->average_tpt = IL_INVALID_VALUE; 682 goto out; 683 684 } 685 686 current_tpt = win->average_tpt; 687 688 high_low = 689 il3945_get_adjacent_rate(rs_sta, idx, rate_mask, sband->band); 690 low = high_low & 0xff; 691 high = (high_low >> 8) & 0xff; 692 693 /* If user set max rate, dont allow higher than user constrain */ 694 if (max_rate_idx != -1 && max_rate_idx < high) 695 high = RATE_INVALID; 696 697 /* Collect Measured throughputs of adjacent rates */ 698 if (low != RATE_INVALID) 699 low_tpt = rs_sta->win[low].average_tpt; 700 701 if (high != RATE_INVALID) 702 high_tpt = rs_sta->win[high].average_tpt; 703 704 spin_unlock_irqrestore(&rs_sta->lock, flags); 705 706 scale_action = 0; 707 708 /* Low success ratio , need to drop the rate */ 709 if (win->success_ratio < RATE_DECREASE_TH || !current_tpt) { 710 D_RATE("decrease rate because of low success_ratio\n"); 711 scale_action = -1; 712 /* No throughput measured yet for adjacent rates, 713 * try increase */ 714 } else if (low_tpt == IL_INVALID_VALUE && high_tpt == IL_INVALID_VALUE) { 715 716 if (high != RATE_INVALID && 717 win->success_ratio >= RATE_INCREASE_TH) 718 scale_action = 1; 719 else if (low != RATE_INVALID) 720 scale_action = 0; 721 722 /* Both adjacent throughputs are measured, but neither one has 723 * better throughput; we're using the best rate, don't change 724 * it! */ 725 } else if (low_tpt != IL_INVALID_VALUE && high_tpt != IL_INVALID_VALUE 726 && low_tpt < current_tpt && high_tpt < current_tpt) { 727 728 D_RATE("No action -- low [%d] & high [%d] < " 729 "current_tpt [%d]\n", low_tpt, high_tpt, current_tpt); 730 scale_action = 0; 731 732 /* At least one of the rates has better throughput */ 733 } else { 734 if (high_tpt != IL_INVALID_VALUE) { 735 736 /* High rate has better throughput, Increase 737 * rate */ 738 if (high_tpt > current_tpt && 739 win->success_ratio >= RATE_INCREASE_TH) 740 scale_action = 1; 741 else { 742 D_RATE("decrease rate because of high tpt\n"); 743 scale_action = 0; 744 } 745 } else if (low_tpt != IL_INVALID_VALUE) { 746 if (low_tpt > current_tpt) { 747 D_RATE("decrease rate because of low tpt\n"); 748 scale_action = -1; 749 } else if (win->success_ratio >= RATE_INCREASE_TH) { 750 /* Lower rate has better 751 * throughput,decrease rate */ 752 scale_action = 1; 753 } 754 } 755 } 756 757 /* Sanity check; asked for decrease, but success rate or throughput 758 * has been good at old rate. Don't change it. */ 759 if (scale_action == -1 && low != RATE_INVALID && 760 (win->success_ratio > RATE_HIGH_TH || 761 current_tpt > 100 * rs_sta->expected_tpt[low])) 762 scale_action = 0; 763 764 switch (scale_action) { 765 case -1: 766 /* Decrease rate */ 767 if (low != RATE_INVALID) 768 idx = low; 769 break; 770 case 1: 771 /* Increase rate */ 772 if (high != RATE_INVALID) 773 idx = high; 774 775 break; 776 case 0: 777 default: 778 /* No change */ 779 break; 780 } 781 782 D_RATE("Selected %d (action %d) - low %d high %d\n", idx, scale_action, 783 low, high); 784 785 out: 786 787 if (sband->band == NL80211_BAND_5GHZ) { 788 if (WARN_ON_ONCE(idx < IL_FIRST_OFDM_RATE)) 789 idx = IL_FIRST_OFDM_RATE; 790 rs_sta->last_txrate_idx = idx; 791 info->control.rates[0].idx = idx - IL_FIRST_OFDM_RATE; 792 } else { 793 rs_sta->last_txrate_idx = idx; 794 info->control.rates[0].idx = rs_sta->last_txrate_idx; 795 } 796 info->control.rates[0].count = 1; 797 798 D_RATE("leave: %d\n", idx); 799 } 800 801 #ifdef CONFIG_MAC80211_DEBUGFS 802 803 static ssize_t 804 il3945_sta_dbgfs_stats_table_read(struct file *file, char __user *user_buf, 805 size_t count, loff_t *ppos) 806 { 807 char *buff; 808 int desc = 0; 809 int j; 810 ssize_t ret; 811 struct il3945_rs_sta *lq_sta = file->private_data; 812 813 buff = kmalloc(1024, GFP_KERNEL); 814 if (!buff) 815 return -ENOMEM; 816 817 desc += 818 sprintf(buff + desc, 819 "tx packets=%d last rate idx=%d\n" 820 "rate=0x%X flush time %d\n", lq_sta->tx_packets, 821 lq_sta->last_txrate_idx, lq_sta->start_rate, 822 jiffies_to_msecs(lq_sta->flush_time)); 823 for (j = 0; j < RATE_COUNT_3945; j++) { 824 desc += 825 sprintf(buff + desc, "counter=%d success=%d %%=%d\n", 826 lq_sta->win[j].counter, 827 lq_sta->win[j].success_counter, 828 lq_sta->win[j].success_ratio); 829 } 830 ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc); 831 kfree(buff); 832 return ret; 833 } 834 835 static const struct file_operations rs_sta_dbgfs_stats_table_ops = { 836 .read = il3945_sta_dbgfs_stats_table_read, 837 .open = simple_open, 838 .llseek = default_llseek, 839 }; 840 841 static void 842 il3945_add_debugfs(void *il, void *il_sta, struct dentry *dir) 843 { 844 struct il3945_rs_sta *lq_sta = il_sta; 845 846 debugfs_create_file("rate_stats_table", 0600, dir, lq_sta, 847 &rs_sta_dbgfs_stats_table_ops); 848 } 849 #endif 850 851 /* 852 * Initialization of rate scaling information is done by driver after 853 * the station is added. Since mac80211 calls this function before a 854 * station is added we ignore it. 855 */ 856 static void 857 il3945_rs_rate_init_stub(void *il_r, struct ieee80211_supported_band *sband, 858 struct cfg80211_chan_def *chandef, 859 struct ieee80211_sta *sta, void *il_sta) 860 { 861 } 862 863 static const struct rate_control_ops rs_ops = { 864 .name = RS_NAME, 865 .tx_status = il3945_rs_tx_status, 866 .get_rate = il3945_rs_get_rate, 867 .rate_init = il3945_rs_rate_init_stub, 868 .alloc = il3945_rs_alloc, 869 .free = il3945_rs_free, 870 .alloc_sta = il3945_rs_alloc_sta, 871 .free_sta = il3945_rs_free_sta, 872 #ifdef CONFIG_MAC80211_DEBUGFS 873 .add_sta_debugfs = il3945_add_debugfs, 874 #endif 875 876 }; 877 878 void 879 il3945_rate_scale_init(struct ieee80211_hw *hw, s32 sta_id) 880 { 881 struct il_priv *il = hw->priv; 882 s32 rssi = 0; 883 unsigned long flags; 884 struct il3945_rs_sta *rs_sta; 885 struct ieee80211_sta *sta; 886 struct il3945_sta_priv *psta; 887 888 D_RATE("enter\n"); 889 890 rcu_read_lock(); 891 892 sta = ieee80211_find_sta(il->vif, il->stations[sta_id].sta.sta.addr); 893 if (!sta) { 894 D_RATE("Unable to find station to initialize rate scaling.\n"); 895 rcu_read_unlock(); 896 return; 897 } 898 899 psta = (void *)sta->drv_priv; 900 rs_sta = &psta->rs_sta; 901 902 spin_lock_irqsave(&rs_sta->lock, flags); 903 904 rs_sta->tgg = 0; 905 switch (il->band) { 906 case NL80211_BAND_2GHZ: 907 /* TODO: this always does G, not a regression */ 908 if (il->active.flags & RXON_FLG_TGG_PROTECT_MSK) { 909 rs_sta->tgg = 1; 910 rs_sta->expected_tpt = il3945_expected_tpt_g_prot; 911 } else 912 rs_sta->expected_tpt = il3945_expected_tpt_g; 913 break; 914 case NL80211_BAND_5GHZ: 915 rs_sta->expected_tpt = il3945_expected_tpt_a; 916 break; 917 default: 918 BUG(); 919 break; 920 } 921 922 spin_unlock_irqrestore(&rs_sta->lock, flags); 923 924 rssi = il->_3945.last_rx_rssi; 925 if (rssi == 0) 926 rssi = IL_MIN_RSSI_VAL; 927 928 D_RATE("Network RSSI: %d\n", rssi); 929 930 rs_sta->start_rate = il3945_get_rate_idx_by_rssi(rssi, il->band); 931 932 D_RATE("leave: rssi %d assign rate idx: " "%d (plcp 0x%x)\n", rssi, 933 rs_sta->start_rate, il3945_rates[rs_sta->start_rate].plcp); 934 rcu_read_unlock(); 935 } 936 937 int 938 il3945_rate_control_register(void) 939 { 940 return ieee80211_rate_control_register(&rs_ops); 941 } 942 943 void 944 il3945_rate_control_unregister(void) 945 { 946 ieee80211_rate_control_unregister(&rs_ops); 947 } 948