1/****************************************************************************** 2 * 3 * Copyright(c) 2005 - 2011 Intel Corporation. All rights reserved. 4 * 5 * This program is free software; you can redistribute it and/or modify it 6 * under the terms of version 2 of the GNU General Public License as 7 * published by the Free Software Foundation. 8 * 9 * This program is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 12 * more details. 13 * 14 * You should have received a copy of the GNU General Public License along with 15 * this program; if not, write to the Free Software Foundation, Inc., 16 * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA 17 * 18 * The full GNU General Public License is included in this distribution in the 19 * file called LICENSE. 20 * 21 * Contact Information: 22 * Intel Linux Wireless <ilw@linux.intel.com> 23 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497 24 * 25 *****************************************************************************/ 26 27#include <linux/kernel.h> 28#include <linux/init.h> 29#include <linux/skbuff.h> 30#include <linux/slab.h> 31#include <net/mac80211.h> 32 33#include <linux/netdevice.h> 34#include <linux/etherdevice.h> 35#include <linux/delay.h> 36 37#include <linux/workqueue.h> 38 39#include "commands.h" 40#include "3945.h" 41 42#define RS_NAME "iwl-3945-rs" 43 44static s32 il3945_expected_tpt_g[RATE_COUNT_3945] = { 45 7, 13, 35, 58, 0, 0, 76, 104, 130, 168, 191, 202 46}; 47 48static s32 il3945_expected_tpt_g_prot[RATE_COUNT_3945] = { 49 7, 13, 35, 58, 0, 0, 0, 80, 93, 113, 123, 125 50}; 51 52static s32 il3945_expected_tpt_a[RATE_COUNT_3945] = { 53 0, 0, 0, 0, 40, 57, 72, 98, 121, 154, 177, 186 54}; 55 56static s32 il3945_expected_tpt_b[RATE_COUNT_3945] = { 57 7, 13, 35, 58, 0, 0, 0, 0, 0, 0, 0, 0 58}; 59 60struct il3945_tpt_entry { 61 s8 min_rssi; 62 u8 idx; 63}; 64 65static struct il3945_tpt_entry il3945_tpt_table_a[] = { 66 {-60, RATE_54M_IDX}, 67 {-64, RATE_48M_IDX}, 68 {-72, RATE_36M_IDX}, 69 {-80, RATE_24M_IDX}, 70 {-84, RATE_18M_IDX}, 71 {-85, RATE_12M_IDX}, 72 {-87, RATE_9M_IDX}, 73 {-89, RATE_6M_IDX} 74}; 75 76static struct il3945_tpt_entry il3945_tpt_table_g[] = { 77 {-60, RATE_54M_IDX}, 78 {-64, RATE_48M_IDX}, 79 {-68, RATE_36M_IDX}, 80 {-80, RATE_24M_IDX}, 81 {-84, RATE_18M_IDX}, 82 {-85, RATE_12M_IDX}, 83 {-86, RATE_11M_IDX}, 84 {-88, RATE_5M_IDX}, 85 {-90, RATE_2M_IDX}, 86 {-92, RATE_1M_IDX} 87}; 88 89#define RATE_MAX_WINDOW 62 90#define RATE_FLUSH (3*HZ) 91#define RATE_WIN_FLUSH (HZ/2) 92#define IL39_RATE_HIGH_TH 11520 93#define IL_SUCCESS_UP_TH 8960 94#define IL_SUCCESS_DOWN_TH 10880 95#define RATE_MIN_FAILURE_TH 6 96#define RATE_MIN_SUCCESS_TH 8 97#define RATE_DECREASE_TH 1920 98#define RATE_RETRY_TH 15 99 100static u8 101il3945_get_rate_idx_by_rssi(s32 rssi, enum ieee80211_band band) 102{ 103 u32 idx = 0; 104 u32 table_size = 0; 105 struct il3945_tpt_entry *tpt_table = NULL; 106 107 if (rssi < IL_MIN_RSSI_VAL || rssi > IL_MAX_RSSI_VAL) 108 rssi = IL_MIN_RSSI_VAL; 109 110 switch (band) { 111 case IEEE80211_BAND_2GHZ: 112 tpt_table = il3945_tpt_table_g; 113 table_size = ARRAY_SIZE(il3945_tpt_table_g); 114 break; 115 case IEEE80211_BAND_5GHZ: 116 tpt_table = il3945_tpt_table_a; 117 table_size = ARRAY_SIZE(il3945_tpt_table_a); 118 break; 119 default: 120 BUG(); 121 break; 122 } 123 124 while (idx < table_size && rssi < tpt_table[idx].min_rssi) 125 idx++; 126 127 idx = min(idx, table_size - 1); 128 129 return tpt_table[idx].idx; 130} 131 132static void 133il3945_clear_win(struct il3945_rate_scale_data *win) 134{ 135 win->data = 0; 136 win->success_counter = 0; 137 win->success_ratio = -1; 138 win->counter = 0; 139 win->average_tpt = IL_INVALID_VALUE; 140 win->stamp = 0; 141} 142 143/** 144 * il3945_rate_scale_flush_wins - flush out the rate scale wins 145 * 146 * Returns the number of wins that have gathered data but were 147 * not flushed. If there were any that were not flushed, then 148 * reschedule the rate flushing routine. 149 */ 150static int 151il3945_rate_scale_flush_wins(struct il3945_rs_sta *rs_sta) 152{ 153 int unflushed = 0; 154 int i; 155 unsigned long flags; 156 struct il_priv *il __maybe_unused = rs_sta->il; 157 158 /* 159 * For each rate, if we have collected data on that rate 160 * and it has been more than RATE_WIN_FLUSH 161 * since we flushed, clear out the gathered stats 162 */ 163 for (i = 0; i < RATE_COUNT_3945; i++) { 164 if (!rs_sta->win[i].counter) 165 continue; 166 167 spin_lock_irqsave(&rs_sta->lock, flags); 168 if (time_after(jiffies, rs_sta->win[i].stamp + RATE_WIN_FLUSH)) { 169 D_RATE("flushing %d samples of rate " "idx %d\n", 170 rs_sta->win[i].counter, i); 171 il3945_clear_win(&rs_sta->win[i]); 172 } else 173 unflushed++; 174 spin_unlock_irqrestore(&rs_sta->lock, flags); 175 } 176 177 return unflushed; 178} 179 180#define RATE_FLUSH_MAX 5000 /* msec */ 181#define RATE_FLUSH_MIN 50 /* msec */ 182#define IL_AVERAGE_PACKETS 1500 183 184static void 185il3945_bg_rate_scale_flush(unsigned long data) 186{ 187 struct il3945_rs_sta *rs_sta = (void *)data; 188 struct il_priv *il __maybe_unused = rs_sta->il; 189 int unflushed = 0; 190 unsigned long flags; 191 u32 packet_count, duration, pps; 192 193 D_RATE("enter\n"); 194 195 unflushed = il3945_rate_scale_flush_wins(rs_sta); 196 197 spin_lock_irqsave(&rs_sta->lock, flags); 198 199 /* Number of packets Rx'd since last time this timer ran */ 200 packet_count = (rs_sta->tx_packets - rs_sta->last_tx_packets) + 1; 201 202 rs_sta->last_tx_packets = rs_sta->tx_packets + 1; 203 204 if (unflushed) { 205 duration = 206 jiffies_to_msecs(jiffies - rs_sta->last_partial_flush); 207 208 D_RATE("Tx'd %d packets in %dms\n", packet_count, duration); 209 210 /* Determine packets per second */ 211 if (duration) 212 pps = (packet_count * 1000) / duration; 213 else 214 pps = 0; 215 216 if (pps) { 217 duration = (IL_AVERAGE_PACKETS * 1000) / pps; 218 if (duration < RATE_FLUSH_MIN) 219 duration = RATE_FLUSH_MIN; 220 else if (duration > RATE_FLUSH_MAX) 221 duration = RATE_FLUSH_MAX; 222 } else 223 duration = RATE_FLUSH_MAX; 224 225 rs_sta->flush_time = msecs_to_jiffies(duration); 226 227 D_RATE("new flush period: %d msec ave %d\n", duration, 228 packet_count); 229 230 mod_timer(&rs_sta->rate_scale_flush, 231 jiffies + rs_sta->flush_time); 232 233 rs_sta->last_partial_flush = jiffies; 234 } else { 235 rs_sta->flush_time = RATE_FLUSH; 236 rs_sta->flush_pending = 0; 237 } 238 /* If there weren't any unflushed entries, we don't schedule the timer 239 * to run again */ 240 241 rs_sta->last_flush = jiffies; 242 243 spin_unlock_irqrestore(&rs_sta->lock, flags); 244 245 D_RATE("leave\n"); 246} 247 248/** 249 * il3945_collect_tx_data - Update the success/failure sliding win 250 * 251 * We keep a sliding win of the last 64 packets transmitted 252 * at this rate. win->data contains the bitmask of successful 253 * packets. 254 */ 255static void 256il3945_collect_tx_data(struct il3945_rs_sta *rs_sta, 257 struct il3945_rate_scale_data *win, int success, 258 int retries, int idx) 259{ 260 unsigned long flags; 261 s32 fail_count; 262 struct il_priv *il __maybe_unused = rs_sta->il; 263 264 if (!retries) { 265 D_RATE("leave: retries == 0 -- should be at least 1\n"); 266 return; 267 } 268 269 spin_lock_irqsave(&rs_sta->lock, flags); 270 271 /* 272 * Keep track of only the latest 62 tx frame attempts in this rate's 273 * history win; anything older isn't really relevant any more. 274 * If we have filled up the sliding win, drop the oldest attempt; 275 * if the oldest attempt (highest bit in bitmap) shows "success", 276 * subtract "1" from the success counter (this is the main reason 277 * we keep these bitmaps!). 278 * */ 279 while (retries > 0) { 280 if (win->counter >= RATE_MAX_WINDOW) { 281 282 /* remove earliest */ 283 win->counter = RATE_MAX_WINDOW - 1; 284 285 if (win->data & (1ULL << (RATE_MAX_WINDOW - 1))) { 286 win->data &= ~(1ULL << (RATE_MAX_WINDOW - 1)); 287 win->success_counter--; 288 } 289 } 290 291 /* Increment frames-attempted counter */ 292 win->counter++; 293 294 /* Shift bitmap by one frame (throw away oldest history), 295 * OR in "1", and increment "success" if this 296 * frame was successful. */ 297 win->data <<= 1; 298 if (success > 0) { 299 win->success_counter++; 300 win->data |= 0x1; 301 success--; 302 } 303 304 retries--; 305 } 306 307 /* Calculate current success ratio, avoid divide-by-0! */ 308 if (win->counter > 0) 309 win->success_ratio = 310 128 * (100 * win->success_counter) / win->counter; 311 else 312 win->success_ratio = IL_INVALID_VALUE; 313 314 fail_count = win->counter - win->success_counter; 315 316 /* Calculate average throughput, if we have enough history. */ 317 if (fail_count >= RATE_MIN_FAILURE_TH || 318 win->success_counter >= RATE_MIN_SUCCESS_TH) 319 win->average_tpt = 320 ((win->success_ratio * rs_sta->expected_tpt[idx] + 321 64) / 128); 322 else 323 win->average_tpt = IL_INVALID_VALUE; 324 325 /* Tag this win as having been updated */ 326 win->stamp = jiffies; 327 328 spin_unlock_irqrestore(&rs_sta->lock, flags); 329} 330 331/* 332 * Called after adding a new station to initialize rate scaling 333 */ 334void 335il3945_rs_rate_init(struct il_priv *il, struct ieee80211_sta *sta, u8 sta_id) 336{ 337 struct ieee80211_hw *hw = il->hw; 338 struct ieee80211_conf *conf = &il->hw->conf; 339 struct il3945_sta_priv *psta; 340 struct il3945_rs_sta *rs_sta; 341 struct ieee80211_supported_band *sband; 342 int i; 343 344 D_INFO("enter\n"); 345 if (sta_id == il->hw_params.bcast_id) 346 goto out; 347 348 psta = (struct il3945_sta_priv *)sta->drv_priv; 349 rs_sta = &psta->rs_sta; 350 sband = hw->wiphy->bands[conf->channel->band]; 351 352 rs_sta->il = il; 353 354 rs_sta->start_rate = RATE_INVALID; 355 356 /* default to just 802.11b */ 357 rs_sta->expected_tpt = il3945_expected_tpt_b; 358 359 rs_sta->last_partial_flush = jiffies; 360 rs_sta->last_flush = jiffies; 361 rs_sta->flush_time = RATE_FLUSH; 362 rs_sta->last_tx_packets = 0; 363 364 rs_sta->rate_scale_flush.data = (unsigned long)rs_sta; 365 rs_sta->rate_scale_flush.function = il3945_bg_rate_scale_flush; 366 367 for (i = 0; i < RATE_COUNT_3945; i++) 368 il3945_clear_win(&rs_sta->win[i]); 369 370 /* TODO: what is a good starting rate for STA? About middle? Maybe not 371 * the lowest or the highest rate.. Could consider using RSSI from 372 * previous packets? Need to have IEEE 802.1X auth succeed immediately 373 * after assoc.. */ 374 375 for (i = sband->n_bitrates - 1; i >= 0; i--) { 376 if (sta->supp_rates[sband->band] & (1 << i)) { 377 rs_sta->last_txrate_idx = i; 378 break; 379 } 380 } 381 382 il->_3945.sta_supp_rates = sta->supp_rates[sband->band]; 383 /* For 5 GHz band it start at IL_FIRST_OFDM_RATE */ 384 if (sband->band == IEEE80211_BAND_5GHZ) { 385 rs_sta->last_txrate_idx += IL_FIRST_OFDM_RATE; 386 il->_3945.sta_supp_rates <<= IL_FIRST_OFDM_RATE; 387 } 388 389out: 390 il->stations[sta_id].used &= ~IL_STA_UCODE_INPROGRESS; 391 392 D_INFO("leave\n"); 393} 394 395static void * 396il3945_rs_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir) 397{ 398 return hw->priv; 399} 400 401/* rate scale requires free function to be implemented */ 402static void 403il3945_rs_free(void *il) 404{ 405} 406 407static void * 408il3945_rs_alloc_sta(void *il_priv, struct ieee80211_sta *sta, gfp_t gfp) 409{ 410 struct il3945_rs_sta *rs_sta; 411 struct il3945_sta_priv *psta = (void *)sta->drv_priv; 412 struct il_priv *il __maybe_unused = il_priv; 413 414 D_RATE("enter\n"); 415 416 rs_sta = &psta->rs_sta; 417 418 spin_lock_init(&rs_sta->lock); 419 init_timer(&rs_sta->rate_scale_flush); 420 421 D_RATE("leave\n"); 422 423 return rs_sta; 424} 425 426static void 427il3945_rs_free_sta(void *il_priv, struct ieee80211_sta *sta, void *il_sta) 428{ 429 struct il3945_rs_sta *rs_sta = il_sta; 430 431 /* 432 * Be careful not to use any members of il3945_rs_sta (like trying 433 * to use il_priv to print out debugging) since it may not be fully 434 * initialized at this point. 435 */ 436 del_timer_sync(&rs_sta->rate_scale_flush); 437} 438 439/** 440 * il3945_rs_tx_status - Update rate control values based on Tx results 441 * 442 * NOTE: Uses il_priv->retry_rate for the # of retries attempted by 443 * the hardware for each rate. 444 */ 445static void 446il3945_rs_tx_status(void *il_rate, struct ieee80211_supported_band *sband, 447 struct ieee80211_sta *sta, void *il_sta, 448 struct sk_buff *skb) 449{ 450 s8 retries = 0, current_count; 451 int scale_rate_idx, first_idx, last_idx; 452 unsigned long flags; 453 struct il_priv *il = (struct il_priv *)il_rate; 454 struct il3945_rs_sta *rs_sta = il_sta; 455 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 456 457 D_RATE("enter\n"); 458 459 retries = info->status.rates[0].count; 460 /* Sanity Check for retries */ 461 if (retries > RATE_RETRY_TH) 462 retries = RATE_RETRY_TH; 463 464 first_idx = sband->bitrates[info->status.rates[0].idx].hw_value; 465 if (first_idx < 0 || first_idx >= RATE_COUNT_3945) { 466 D_RATE("leave: Rate out of bounds: %d\n", first_idx); 467 return; 468 } 469 470 if (!il_sta) { 471 D_RATE("leave: No STA il data to update!\n"); 472 return; 473 } 474 475 /* Treat uninitialized rate scaling data same as non-existing. */ 476 if (!rs_sta->il) { 477 D_RATE("leave: STA il data uninitialized!\n"); 478 return; 479 } 480 481 rs_sta->tx_packets++; 482 483 scale_rate_idx = first_idx; 484 last_idx = first_idx; 485 486 /* 487 * Update the win for each rate. We determine which rates 488 * were Tx'd based on the total number of retries vs. the number 489 * of retries configured for each rate -- currently set to the 490 * il value 'retry_rate' vs. rate specific 491 * 492 * On exit from this while loop last_idx indicates the rate 493 * at which the frame was finally transmitted (or failed if no 494 * ACK) 495 */ 496 while (retries > 1) { 497 if ((retries - 1) < il->retry_rate) { 498 current_count = (retries - 1); 499 last_idx = scale_rate_idx; 500 } else { 501 current_count = il->retry_rate; 502 last_idx = il3945_rs_next_rate(il, scale_rate_idx); 503 } 504 505 /* Update this rate accounting for as many retries 506 * as was used for it (per current_count) */ 507 il3945_collect_tx_data(rs_sta, &rs_sta->win[scale_rate_idx], 0, 508 current_count, scale_rate_idx); 509 D_RATE("Update rate %d for %d retries.\n", scale_rate_idx, 510 current_count); 511 512 retries -= current_count; 513 514 scale_rate_idx = last_idx; 515 } 516 517 /* Update the last idx win with success/failure based on ACK */ 518 D_RATE("Update rate %d with %s.\n", last_idx, 519 (info->flags & IEEE80211_TX_STAT_ACK) ? "success" : "failure"); 520 il3945_collect_tx_data(rs_sta, &rs_sta->win[last_idx], 521 info->flags & IEEE80211_TX_STAT_ACK, 1, 522 last_idx); 523 524 /* We updated the rate scale win -- if its been more than 525 * flush_time since the last run, schedule the flush 526 * again */ 527 spin_lock_irqsave(&rs_sta->lock, flags); 528 529 if (!rs_sta->flush_pending && 530 time_after(jiffies, rs_sta->last_flush + rs_sta->flush_time)) { 531 532 rs_sta->last_partial_flush = jiffies; 533 rs_sta->flush_pending = 1; 534 mod_timer(&rs_sta->rate_scale_flush, 535 jiffies + rs_sta->flush_time); 536 } 537 538 spin_unlock_irqrestore(&rs_sta->lock, flags); 539 540 D_RATE("leave\n"); 541} 542 543static u16 544il3945_get_adjacent_rate(struct il3945_rs_sta *rs_sta, u8 idx, u16 rate_mask, 545 enum ieee80211_band band) 546{ 547 u8 high = RATE_INVALID; 548 u8 low = RATE_INVALID; 549 struct il_priv *il __maybe_unused = rs_sta->il; 550 551 /* 802.11A walks to the next literal adjacent rate in 552 * the rate table */ 553 if (unlikely(band == IEEE80211_BAND_5GHZ)) { 554 int i; 555 u32 mask; 556 557 /* Find the previous rate that is in the rate mask */ 558 i = idx - 1; 559 for (mask = (1 << i); i >= 0; i--, mask >>= 1) { 560 if (rate_mask & mask) { 561 low = i; 562 break; 563 } 564 } 565 566 /* Find the next rate that is in the rate mask */ 567 i = idx + 1; 568 for (mask = (1 << i); i < RATE_COUNT_3945; i++, mask <<= 1) { 569 if (rate_mask & mask) { 570 high = i; 571 break; 572 } 573 } 574 575 return (high << 8) | low; 576 } 577 578 low = idx; 579 while (low != RATE_INVALID) { 580 if (rs_sta->tgg) 581 low = il3945_rates[low].prev_rs_tgg; 582 else 583 low = il3945_rates[low].prev_rs; 584 if (low == RATE_INVALID) 585 break; 586 if (rate_mask & (1 << low)) 587 break; 588 D_RATE("Skipping masked lower rate: %d\n", low); 589 } 590 591 high = idx; 592 while (high != RATE_INVALID) { 593 if (rs_sta->tgg) 594 high = il3945_rates[high].next_rs_tgg; 595 else 596 high = il3945_rates[high].next_rs; 597 if (high == RATE_INVALID) 598 break; 599 if (rate_mask & (1 << high)) 600 break; 601 D_RATE("Skipping masked higher rate: %d\n", high); 602 } 603 604 return (high << 8) | low; 605} 606 607/** 608 * il3945_rs_get_rate - find the rate for the requested packet 609 * 610 * Returns the ieee80211_rate structure allocated by the driver. 611 * 612 * The rate control algorithm has no internal mapping between hw_mode's 613 * rate ordering and the rate ordering used by the rate control algorithm. 614 * 615 * The rate control algorithm uses a single table of rates that goes across 616 * the entire A/B/G spectrum vs. being limited to just one particular 617 * hw_mode. 618 * 619 * As such, we can't convert the idx obtained below into the hw_mode's 620 * rate table and must reference the driver allocated rate table 621 * 622 */ 623static void 624il3945_rs_get_rate(void *il_r, struct ieee80211_sta *sta, void *il_sta, 625 struct ieee80211_tx_rate_control *txrc) 626{ 627 struct ieee80211_supported_band *sband = txrc->sband; 628 struct sk_buff *skb = txrc->skb; 629 u8 low = RATE_INVALID; 630 u8 high = RATE_INVALID; 631 u16 high_low; 632 int idx; 633 struct il3945_rs_sta *rs_sta = il_sta; 634 struct il3945_rate_scale_data *win = NULL; 635 int current_tpt = IL_INVALID_VALUE; 636 int low_tpt = IL_INVALID_VALUE; 637 int high_tpt = IL_INVALID_VALUE; 638 u32 fail_count; 639 s8 scale_action = 0; 640 unsigned long flags; 641 u16 rate_mask; 642 s8 max_rate_idx = -1; 643 struct il_priv *il __maybe_unused = (struct il_priv *)il_r; 644 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 645 646 D_RATE("enter\n"); 647 648 /* Treat uninitialized rate scaling data same as non-existing. */ 649 if (rs_sta && !rs_sta->il) { 650 D_RATE("Rate scaling information not initialized yet.\n"); 651 il_sta = NULL; 652 } 653 654 if (rate_control_send_low(sta, il_sta, txrc)) 655 return; 656 657 rate_mask = sta->supp_rates[sband->band]; 658 659 /* get user max rate if set */ 660 max_rate_idx = txrc->max_rate_idx; 661 if (sband->band == IEEE80211_BAND_5GHZ && max_rate_idx != -1) 662 max_rate_idx += IL_FIRST_OFDM_RATE; 663 if (max_rate_idx < 0 || max_rate_idx >= RATE_COUNT) 664 max_rate_idx = -1; 665 666 idx = min(rs_sta->last_txrate_idx & 0xffff, RATE_COUNT_3945 - 1); 667 668 if (sband->band == IEEE80211_BAND_5GHZ) 669 rate_mask = rate_mask << IL_FIRST_OFDM_RATE; 670 671 spin_lock_irqsave(&rs_sta->lock, flags); 672 673 /* for recent assoc, choose best rate regarding 674 * to rssi value 675 */ 676 if (rs_sta->start_rate != RATE_INVALID) { 677 if (rs_sta->start_rate < idx && 678 (rate_mask & (1 << rs_sta->start_rate))) 679 idx = rs_sta->start_rate; 680 rs_sta->start_rate = RATE_INVALID; 681 } 682 683 /* force user max rate if set by user */ 684 if (max_rate_idx != -1 && max_rate_idx < idx) { 685 if (rate_mask & (1 << max_rate_idx)) 686 idx = max_rate_idx; 687 } 688 689 win = &(rs_sta->win[idx]); 690 691 fail_count = win->counter - win->success_counter; 692 693 if (fail_count < RATE_MIN_FAILURE_TH && 694 win->success_counter < RATE_MIN_SUCCESS_TH) { 695 spin_unlock_irqrestore(&rs_sta->lock, flags); 696 697 D_RATE("Invalid average_tpt on rate %d: " 698 "counter: %d, success_counter: %d, " 699 "expected_tpt is %sNULL\n", idx, win->counter, 700 win->success_counter, 701 rs_sta->expected_tpt ? "not " : ""); 702 703 /* Can't calculate this yet; not enough history */ 704 win->average_tpt = IL_INVALID_VALUE; 705 goto out; 706 707 } 708 709 current_tpt = win->average_tpt; 710 711 high_low = 712 il3945_get_adjacent_rate(rs_sta, idx, rate_mask, sband->band); 713 low = high_low & 0xff; 714 high = (high_low >> 8) & 0xff; 715 716 /* If user set max rate, dont allow higher than user constrain */ 717 if (max_rate_idx != -1 && max_rate_idx < high) 718 high = RATE_INVALID; 719 720 /* Collect Measured throughputs of adjacent rates */ 721 if (low != RATE_INVALID) 722 low_tpt = rs_sta->win[low].average_tpt; 723 724 if (high != RATE_INVALID) 725 high_tpt = rs_sta->win[high].average_tpt; 726 727 spin_unlock_irqrestore(&rs_sta->lock, flags); 728 729 scale_action = 0; 730 731 /* Low success ratio , need to drop the rate */ 732 if (win->success_ratio < RATE_DECREASE_TH || !current_tpt) { 733 D_RATE("decrease rate because of low success_ratio\n"); 734 scale_action = -1; 735 /* No throughput measured yet for adjacent rates, 736 * try increase */ 737 } else if (low_tpt == IL_INVALID_VALUE && high_tpt == IL_INVALID_VALUE) { 738 739 if (high != RATE_INVALID && 740 win->success_ratio >= RATE_INCREASE_TH) 741 scale_action = 1; 742 else if (low != RATE_INVALID) 743 scale_action = 0; 744 745 /* Both adjacent throughputs are measured, but neither one has 746 * better throughput; we're using the best rate, don't change 747 * it! */ 748 } else if (low_tpt != IL_INVALID_VALUE && high_tpt != IL_INVALID_VALUE 749 && low_tpt < current_tpt && high_tpt < current_tpt) { 750 751 D_RATE("No action -- low [%d] & high [%d] < " 752 "current_tpt [%d]\n", low_tpt, high_tpt, current_tpt); 753 scale_action = 0; 754 755 /* At least one of the rates has better throughput */ 756 } else { 757 if (high_tpt != IL_INVALID_VALUE) { 758 759 /* High rate has better throughput, Increase 760 * rate */ 761 if (high_tpt > current_tpt && 762 win->success_ratio >= RATE_INCREASE_TH) 763 scale_action = 1; 764 else { 765 D_RATE("decrease rate because of high tpt\n"); 766 scale_action = 0; 767 } 768 } else if (low_tpt != IL_INVALID_VALUE) { 769 if (low_tpt > current_tpt) { 770 D_RATE("decrease rate because of low tpt\n"); 771 scale_action = -1; 772 } else if (win->success_ratio >= RATE_INCREASE_TH) { 773 /* Lower rate has better 774 * throughput,decrease rate */ 775 scale_action = 1; 776 } 777 } 778 } 779 780 /* Sanity check; asked for decrease, but success rate or throughput 781 * has been good at old rate. Don't change it. */ 782 if (scale_action == -1 && low != RATE_INVALID && 783 (win->success_ratio > RATE_HIGH_TH || 784 current_tpt > 100 * rs_sta->expected_tpt[low])) 785 scale_action = 0; 786 787 switch (scale_action) { 788 case -1: 789 /* Decrese rate */ 790 if (low != RATE_INVALID) 791 idx = low; 792 break; 793 case 1: 794 /* Increase rate */ 795 if (high != RATE_INVALID) 796 idx = high; 797 798 break; 799 case 0: 800 default: 801 /* No change */ 802 break; 803 } 804 805 D_RATE("Selected %d (action %d) - low %d high %d\n", idx, scale_action, 806 low, high); 807 808out: 809 810 if (sband->band == IEEE80211_BAND_5GHZ) { 811 if (WARN_ON_ONCE(idx < IL_FIRST_OFDM_RATE)) 812 idx = IL_FIRST_OFDM_RATE; 813 rs_sta->last_txrate_idx = idx; 814 info->control.rates[0].idx = idx - IL_FIRST_OFDM_RATE; 815 } else { 816 rs_sta->last_txrate_idx = idx; 817 info->control.rates[0].idx = rs_sta->last_txrate_idx; 818 } 819 820 D_RATE("leave: %d\n", idx); 821} 822 823#ifdef CONFIG_MAC80211_DEBUGFS 824 825static ssize_t 826il3945_sta_dbgfs_stats_table_read(struct file *file, char __user *user_buf, 827 size_t count, loff_t *ppos) 828{ 829 char *buff; 830 int desc = 0; 831 int j; 832 ssize_t ret; 833 struct il3945_rs_sta *lq_sta = file->private_data; 834 835 buff = kmalloc(1024, GFP_KERNEL); 836 if (!buff) 837 return -ENOMEM; 838 839 desc += 840 sprintf(buff + desc, 841 "tx packets=%d last rate idx=%d\n" 842 "rate=0x%X flush time %d\n", lq_sta->tx_packets, 843 lq_sta->last_txrate_idx, lq_sta->start_rate, 844 jiffies_to_msecs(lq_sta->flush_time)); 845 for (j = 0; j < RATE_COUNT_3945; j++) { 846 desc += 847 sprintf(buff + desc, "counter=%d success=%d %%=%d\n", 848 lq_sta->win[j].counter, 849 lq_sta->win[j].success_counter, 850 lq_sta->win[j].success_ratio); 851 } 852 ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc); 853 kfree(buff); 854 return ret; 855} 856 857static const struct file_operations rs_sta_dbgfs_stats_table_ops = { 858 .read = il3945_sta_dbgfs_stats_table_read, 859 .open = simple_open, 860 .llseek = default_llseek, 861}; 862 863static void 864il3945_add_debugfs(void *il, void *il_sta, struct dentry *dir) 865{ 866 struct il3945_rs_sta *lq_sta = il_sta; 867 868 lq_sta->rs_sta_dbgfs_stats_table_file = 869 debugfs_create_file("rate_stats_table", 0600, dir, lq_sta, 870 &rs_sta_dbgfs_stats_table_ops); 871 872} 873 874static void 875il3945_remove_debugfs(void *il, void *il_sta) 876{ 877 struct il3945_rs_sta *lq_sta = il_sta; 878 debugfs_remove(lq_sta->rs_sta_dbgfs_stats_table_file); 879} 880#endif 881 882/* 883 * Initialization of rate scaling information is done by driver after 884 * the station is added. Since mac80211 calls this function before a 885 * station is added we ignore it. 886 */ 887static void 888il3945_rs_rate_init_stub(void *il_r, struct ieee80211_supported_band *sband, 889 struct ieee80211_sta *sta, void *il_sta) 890{ 891} 892 893static struct rate_control_ops rs_ops = { 894 .module = NULL, 895 .name = RS_NAME, 896 .tx_status = il3945_rs_tx_status, 897 .get_rate = il3945_rs_get_rate, 898 .rate_init = il3945_rs_rate_init_stub, 899 .alloc = il3945_rs_alloc, 900 .free = il3945_rs_free, 901 .alloc_sta = il3945_rs_alloc_sta, 902 .free_sta = il3945_rs_free_sta, 903#ifdef CONFIG_MAC80211_DEBUGFS 904 .add_sta_debugfs = il3945_add_debugfs, 905 .remove_sta_debugfs = il3945_remove_debugfs, 906#endif 907 908}; 909 910void 911il3945_rate_scale_init(struct ieee80211_hw *hw, s32 sta_id) 912{ 913 struct il_priv *il = hw->priv; 914 s32 rssi = 0; 915 unsigned long flags; 916 struct il3945_rs_sta *rs_sta; 917 struct ieee80211_sta *sta; 918 struct il3945_sta_priv *psta; 919 920 D_RATE("enter\n"); 921 922 rcu_read_lock(); 923 924 sta = ieee80211_find_sta(il->vif, il->stations[sta_id].sta.sta.addr); 925 if (!sta) { 926 D_RATE("Unable to find station to initialize rate scaling.\n"); 927 rcu_read_unlock(); 928 return; 929 } 930 931 psta = (void *)sta->drv_priv; 932 rs_sta = &psta->rs_sta; 933 934 spin_lock_irqsave(&rs_sta->lock, flags); 935 936 rs_sta->tgg = 0; 937 switch (il->band) { 938 case IEEE80211_BAND_2GHZ: 939 /* TODO: this always does G, not a regression */ 940 if (il->active.flags & RXON_FLG_TGG_PROTECT_MSK) { 941 rs_sta->tgg = 1; 942 rs_sta->expected_tpt = il3945_expected_tpt_g_prot; 943 } else 944 rs_sta->expected_tpt = il3945_expected_tpt_g; 945 break; 946 case IEEE80211_BAND_5GHZ: 947 rs_sta->expected_tpt = il3945_expected_tpt_a; 948 break; 949 case IEEE80211_NUM_BANDS: 950 BUG(); 951 break; 952 } 953 954 spin_unlock_irqrestore(&rs_sta->lock, flags); 955 956 rssi = il->_3945.last_rx_rssi; 957 if (rssi == 0) 958 rssi = IL_MIN_RSSI_VAL; 959 960 D_RATE("Network RSSI: %d\n", rssi); 961 962 rs_sta->start_rate = il3945_get_rate_idx_by_rssi(rssi, il->band); 963 964 D_RATE("leave: rssi %d assign rate idx: " "%d (plcp 0x%x)\n", rssi, 965 rs_sta->start_rate, il3945_rates[rs_sta->start_rate].plcp); 966 rcu_read_unlock(); 967} 968 969int 970il3945_rate_control_register(void) 971{ 972 return ieee80211_rate_control_register(&rs_ops); 973} 974 975void 976il3945_rate_control_unregister(void) 977{ 978 ieee80211_rate_control_unregister(&rs_ops); 979} 980