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/skbuff.h> 29 #include <linux/slab.h> 30 #include <net/mac80211.h> 31 32 #include <linux/netdevice.h> 33 #include <linux/etherdevice.h> 34 #include <linux/delay.h> 35 36 #include <linux/workqueue.h> 37 38 #include "commands.h" 39 #include "3945.h" 40 41 #define RS_NAME "iwl-3945-rs" 42 43 static s32 il3945_expected_tpt_g[RATE_COUNT_3945] = { 44 7, 13, 35, 58, 0, 0, 76, 104, 130, 168, 191, 202 45 }; 46 47 static s32 il3945_expected_tpt_g_prot[RATE_COUNT_3945] = { 48 7, 13, 35, 58, 0, 0, 0, 80, 93, 113, 123, 125 49 }; 50 51 static s32 il3945_expected_tpt_a[RATE_COUNT_3945] = { 52 0, 0, 0, 0, 40, 57, 72, 98, 121, 154, 177, 186 53 }; 54 55 static s32 il3945_expected_tpt_b[RATE_COUNT_3945] = { 56 7, 13, 35, 58, 0, 0, 0, 0, 0, 0, 0, 0 57 }; 58 59 struct il3945_tpt_entry { 60 s8 min_rssi; 61 u8 idx; 62 }; 63 64 static struct il3945_tpt_entry il3945_tpt_table_a[] = { 65 {-60, RATE_54M_IDX}, 66 {-64, RATE_48M_IDX}, 67 {-72, RATE_36M_IDX}, 68 {-80, RATE_24M_IDX}, 69 {-84, RATE_18M_IDX}, 70 {-85, RATE_12M_IDX}, 71 {-87, RATE_9M_IDX}, 72 {-89, RATE_6M_IDX} 73 }; 74 75 static struct il3945_tpt_entry il3945_tpt_table_g[] = { 76 {-60, RATE_54M_IDX}, 77 {-64, RATE_48M_IDX}, 78 {-68, RATE_36M_IDX}, 79 {-80, RATE_24M_IDX}, 80 {-84, RATE_18M_IDX}, 81 {-85, RATE_12M_IDX}, 82 {-86, RATE_11M_IDX}, 83 {-88, RATE_5M_IDX}, 84 {-90, RATE_2M_IDX}, 85 {-92, RATE_1M_IDX} 86 }; 87 88 #define RATE_MAX_WINDOW 62 89 #define RATE_FLUSH (3*HZ) 90 #define RATE_WIN_FLUSH (HZ/2) 91 #define IL39_RATE_HIGH_TH 11520 92 #define IL_SUCCESS_UP_TH 8960 93 #define IL_SUCCESS_DOWN_TH 10880 94 #define RATE_MIN_FAILURE_TH 6 95 #define RATE_MIN_SUCCESS_TH 8 96 #define RATE_DECREASE_TH 1920 97 #define RATE_RETRY_TH 15 98 99 static u8 100 il3945_get_rate_idx_by_rssi(s32 rssi, enum nl80211_band band) 101 { 102 u32 idx = 0; 103 u32 table_size = 0; 104 struct il3945_tpt_entry *tpt_table = NULL; 105 106 if (rssi < IL_MIN_RSSI_VAL || rssi > IL_MAX_RSSI_VAL) 107 rssi = IL_MIN_RSSI_VAL; 108 109 switch (band) { 110 case NL80211_BAND_2GHZ: 111 tpt_table = il3945_tpt_table_g; 112 table_size = ARRAY_SIZE(il3945_tpt_table_g); 113 break; 114 case NL80211_BAND_5GHZ: 115 tpt_table = il3945_tpt_table_a; 116 table_size = ARRAY_SIZE(il3945_tpt_table_a); 117 break; 118 default: 119 BUG(); 120 break; 121 } 122 123 while (idx < table_size && rssi < tpt_table[idx].min_rssi) 124 idx++; 125 126 idx = min(idx, table_size - 1); 127 128 return tpt_table[idx].idx; 129 } 130 131 static void 132 il3945_clear_win(struct il3945_rate_scale_data *win) 133 { 134 win->data = 0; 135 win->success_counter = 0; 136 win->success_ratio = -1; 137 win->counter = 0; 138 win->average_tpt = IL_INVALID_VALUE; 139 win->stamp = 0; 140 } 141 142 /** 143 * il3945_rate_scale_flush_wins - flush out the rate scale wins 144 * 145 * Returns the number of wins that have gathered data but were 146 * not flushed. If there were any that were not flushed, then 147 * reschedule the rate flushing routine. 148 */ 149 static int 150 il3945_rate_scale_flush_wins(struct il3945_rs_sta *rs_sta) 151 { 152 int unflushed = 0; 153 int i; 154 unsigned long flags; 155 struct il_priv *il __maybe_unused = rs_sta->il; 156 157 /* 158 * For each rate, if we have collected data on that rate 159 * and it has been more than RATE_WIN_FLUSH 160 * since we flushed, clear out the gathered stats 161 */ 162 for (i = 0; i < RATE_COUNT_3945; i++) { 163 if (!rs_sta->win[i].counter) 164 continue; 165 166 spin_lock_irqsave(&rs_sta->lock, flags); 167 if (time_after(jiffies, rs_sta->win[i].stamp + RATE_WIN_FLUSH)) { 168 D_RATE("flushing %d samples of rate " "idx %d\n", 169 rs_sta->win[i].counter, i); 170 il3945_clear_win(&rs_sta->win[i]); 171 } else 172 unflushed++; 173 spin_unlock_irqrestore(&rs_sta->lock, flags); 174 } 175 176 return unflushed; 177 } 178 179 #define RATE_FLUSH_MAX 5000 /* msec */ 180 #define RATE_FLUSH_MIN 50 /* msec */ 181 #define IL_AVERAGE_PACKETS 1500 182 183 static void 184 il3945_bg_rate_scale_flush(struct timer_list *t) 185 { 186 struct il3945_rs_sta *rs_sta = from_timer(rs_sta, t, rate_scale_flush); 187 struct il_priv *il __maybe_unused = rs_sta->il; 188 int unflushed = 0; 189 unsigned long flags; 190 u32 packet_count, duration, pps; 191 192 D_RATE("enter\n"); 193 194 unflushed = il3945_rate_scale_flush_wins(rs_sta); 195 196 spin_lock_irqsave(&rs_sta->lock, flags); 197 198 /* Number of packets Rx'd since last time this timer ran */ 199 packet_count = (rs_sta->tx_packets - rs_sta->last_tx_packets) + 1; 200 201 rs_sta->last_tx_packets = rs_sta->tx_packets + 1; 202 203 if (unflushed) { 204 duration = 205 jiffies_to_msecs(jiffies - rs_sta->last_partial_flush); 206 207 D_RATE("Tx'd %d packets in %dms\n", packet_count, duration); 208 209 /* Determine packets per second */ 210 if (duration) 211 pps = (packet_count * 1000) / duration; 212 else 213 pps = 0; 214 215 if (pps) { 216 duration = (IL_AVERAGE_PACKETS * 1000) / pps; 217 if (duration < RATE_FLUSH_MIN) 218 duration = RATE_FLUSH_MIN; 219 else if (duration > RATE_FLUSH_MAX) 220 duration = RATE_FLUSH_MAX; 221 } else 222 duration = RATE_FLUSH_MAX; 223 224 rs_sta->flush_time = msecs_to_jiffies(duration); 225 226 D_RATE("new flush period: %d msec ave %d\n", duration, 227 packet_count); 228 229 mod_timer(&rs_sta->rate_scale_flush, 230 jiffies + rs_sta->flush_time); 231 232 rs_sta->last_partial_flush = jiffies; 233 } else { 234 rs_sta->flush_time = RATE_FLUSH; 235 rs_sta->flush_pending = 0; 236 } 237 /* If there weren't any unflushed entries, we don't schedule the timer 238 * to run again */ 239 240 rs_sta->last_flush = jiffies; 241 242 spin_unlock_irqrestore(&rs_sta->lock, flags); 243 244 D_RATE("leave\n"); 245 } 246 247 /** 248 * il3945_collect_tx_data - Update the success/failure sliding win 249 * 250 * We keep a sliding win of the last 64 packets transmitted 251 * at this rate. win->data contains the bitmask of successful 252 * packets. 253 */ 254 static void 255 il3945_collect_tx_data(struct il3945_rs_sta *rs_sta, 256 struct il3945_rate_scale_data *win, int success, 257 int retries, int idx) 258 { 259 unsigned long flags; 260 s32 fail_count; 261 struct il_priv *il __maybe_unused = rs_sta->il; 262 263 if (!retries) { 264 D_RATE("leave: retries == 0 -- should be at least 1\n"); 265 return; 266 } 267 268 spin_lock_irqsave(&rs_sta->lock, flags); 269 270 /* 271 * Keep track of only the latest 62 tx frame attempts in this rate's 272 * history win; anything older isn't really relevant any more. 273 * If we have filled up the sliding win, drop the oldest attempt; 274 * if the oldest attempt (highest bit in bitmap) shows "success", 275 * subtract "1" from the success counter (this is the main reason 276 * we keep these bitmaps!). 277 * */ 278 while (retries > 0) { 279 if (win->counter >= RATE_MAX_WINDOW) { 280 281 /* remove earliest */ 282 win->counter = RATE_MAX_WINDOW - 1; 283 284 if (win->data & (1ULL << (RATE_MAX_WINDOW - 1))) { 285 win->data &= ~(1ULL << (RATE_MAX_WINDOW - 1)); 286 win->success_counter--; 287 } 288 } 289 290 /* Increment frames-attempted counter */ 291 win->counter++; 292 293 /* Shift bitmap by one frame (throw away oldest history), 294 * OR in "1", and increment "success" if this 295 * frame was successful. */ 296 win->data <<= 1; 297 if (success > 0) { 298 win->success_counter++; 299 win->data |= 0x1; 300 success--; 301 } 302 303 retries--; 304 } 305 306 /* Calculate current success ratio, avoid divide-by-0! */ 307 if (win->counter > 0) 308 win->success_ratio = 309 128 * (100 * win->success_counter) / win->counter; 310 else 311 win->success_ratio = IL_INVALID_VALUE; 312 313 fail_count = win->counter - win->success_counter; 314 315 /* Calculate average throughput, if we have enough history. */ 316 if (fail_count >= RATE_MIN_FAILURE_TH || 317 win->success_counter >= RATE_MIN_SUCCESS_TH) 318 win->average_tpt = 319 ((win->success_ratio * rs_sta->expected_tpt[idx] + 320 64) / 128); 321 else 322 win->average_tpt = IL_INVALID_VALUE; 323 324 /* Tag this win as having been updated */ 325 win->stamp = jiffies; 326 327 spin_unlock_irqrestore(&rs_sta->lock, flags); 328 } 329 330 /* 331 * Called after adding a new station to initialize rate scaling 332 */ 333 void 334 il3945_rs_rate_init(struct il_priv *il, struct ieee80211_sta *sta, u8 sta_id) 335 { 336 struct ieee80211_hw *hw = il->hw; 337 struct ieee80211_conf *conf = &il->hw->conf; 338 struct il3945_sta_priv *psta; 339 struct il3945_rs_sta *rs_sta; 340 struct ieee80211_supported_band *sband; 341 int i; 342 343 D_INFO("enter\n"); 344 if (sta_id == il->hw_params.bcast_id) 345 goto out; 346 347 psta = (struct il3945_sta_priv *)sta->drv_priv; 348 rs_sta = &psta->rs_sta; 349 sband = hw->wiphy->bands[conf->chandef.chan->band]; 350 351 rs_sta->il = il; 352 353 rs_sta->start_rate = RATE_INVALID; 354 355 /* default to just 802.11b */ 356 rs_sta->expected_tpt = il3945_expected_tpt_b; 357 358 rs_sta->last_partial_flush = jiffies; 359 rs_sta->last_flush = jiffies; 360 rs_sta->flush_time = RATE_FLUSH; 361 rs_sta->last_tx_packets = 0; 362 363 for (i = 0; i < RATE_COUNT_3945; i++) 364 il3945_clear_win(&rs_sta->win[i]); 365 366 /* TODO: what is a good starting rate for STA? About middle? Maybe not 367 * the lowest or the highest rate.. Could consider using RSSI from 368 * previous packets? Need to have IEEE 802.1X auth succeed immediately 369 * after assoc.. */ 370 371 for (i = sband->n_bitrates - 1; i >= 0; i--) { 372 if (sta->supp_rates[sband->band] & (1 << i)) { 373 rs_sta->last_txrate_idx = i; 374 break; 375 } 376 } 377 378 il->_3945.sta_supp_rates = sta->supp_rates[sband->band]; 379 /* For 5 GHz band it start at IL_FIRST_OFDM_RATE */ 380 if (sband->band == NL80211_BAND_5GHZ) { 381 rs_sta->last_txrate_idx += IL_FIRST_OFDM_RATE; 382 il->_3945.sta_supp_rates <<= IL_FIRST_OFDM_RATE; 383 } 384 385 out: 386 il->stations[sta_id].used &= ~IL_STA_UCODE_INPROGRESS; 387 388 D_INFO("leave\n"); 389 } 390 391 static void * 392 il3945_rs_alloc(struct ieee80211_hw *hw, struct dentry *debugfsdir) 393 { 394 return hw->priv; 395 } 396 397 /* rate scale requires free function to be implemented */ 398 static void 399 il3945_rs_free(void *il) 400 { 401 } 402 403 static void * 404 il3945_rs_alloc_sta(void *il_priv, struct ieee80211_sta *sta, gfp_t gfp) 405 { 406 struct il3945_rs_sta *rs_sta; 407 struct il3945_sta_priv *psta = (void *)sta->drv_priv; 408 struct il_priv *il __maybe_unused = il_priv; 409 410 D_RATE("enter\n"); 411 412 rs_sta = &psta->rs_sta; 413 414 spin_lock_init(&rs_sta->lock); 415 timer_setup(&rs_sta->rate_scale_flush, il3945_bg_rate_scale_flush, 0); 416 D_RATE("leave\n"); 417 418 return rs_sta; 419 } 420 421 static void 422 il3945_rs_free_sta(void *il_priv, struct ieee80211_sta *sta, void *il_sta) 423 { 424 struct il3945_rs_sta *rs_sta = il_sta; 425 426 /* 427 * Be careful not to use any members of il3945_rs_sta (like trying 428 * to use il_priv to print out debugging) since it may not be fully 429 * initialized at this point. 430 */ 431 del_timer_sync(&rs_sta->rate_scale_flush); 432 } 433 434 /** 435 * il3945_rs_tx_status - Update rate control values based on Tx results 436 * 437 * NOTE: Uses il_priv->retry_rate for the # of retries attempted by 438 * the hardware for each rate. 439 */ 440 static void 441 il3945_rs_tx_status(void *il_rate, struct ieee80211_supported_band *sband, 442 struct ieee80211_sta *sta, void *il_sta, 443 struct sk_buff *skb) 444 { 445 s8 retries = 0, current_count; 446 int scale_rate_idx, first_idx, last_idx; 447 unsigned long flags; 448 struct il_priv *il = (struct il_priv *)il_rate; 449 struct il3945_rs_sta *rs_sta = il_sta; 450 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 451 452 D_RATE("enter\n"); 453 454 retries = info->status.rates[0].count; 455 /* Sanity Check for retries */ 456 if (retries > RATE_RETRY_TH) 457 retries = RATE_RETRY_TH; 458 459 first_idx = sband->bitrates[info->status.rates[0].idx].hw_value; 460 if (first_idx < 0 || first_idx >= RATE_COUNT_3945) { 461 D_RATE("leave: Rate out of bounds: %d\n", first_idx); 462 return; 463 } 464 465 if (!il_sta) { 466 D_RATE("leave: No STA il data to update!\n"); 467 return; 468 } 469 470 /* Treat uninitialized rate scaling data same as non-existing. */ 471 if (!rs_sta->il) { 472 D_RATE("leave: STA il data uninitialized!\n"); 473 return; 474 } 475 476 rs_sta->tx_packets++; 477 478 scale_rate_idx = first_idx; 479 last_idx = first_idx; 480 481 /* 482 * Update the win for each rate. We determine which rates 483 * were Tx'd based on the total number of retries vs. the number 484 * of retries configured for each rate -- currently set to the 485 * il value 'retry_rate' vs. rate specific 486 * 487 * On exit from this while loop last_idx indicates the rate 488 * at which the frame was finally transmitted (or failed if no 489 * ACK) 490 */ 491 while (retries > 1) { 492 if ((retries - 1) < il->retry_rate) { 493 current_count = (retries - 1); 494 last_idx = scale_rate_idx; 495 } else { 496 current_count = il->retry_rate; 497 last_idx = il3945_rs_next_rate(il, scale_rate_idx); 498 } 499 500 /* Update this rate accounting for as many retries 501 * as was used for it (per current_count) */ 502 il3945_collect_tx_data(rs_sta, &rs_sta->win[scale_rate_idx], 0, 503 current_count, scale_rate_idx); 504 D_RATE("Update rate %d for %d retries.\n", scale_rate_idx, 505 current_count); 506 507 retries -= current_count; 508 509 scale_rate_idx = last_idx; 510 } 511 512 /* Update the last idx win with success/failure based on ACK */ 513 D_RATE("Update rate %d with %s.\n", last_idx, 514 (info->flags & IEEE80211_TX_STAT_ACK) ? "success" : "failure"); 515 il3945_collect_tx_data(rs_sta, &rs_sta->win[last_idx], 516 info->flags & IEEE80211_TX_STAT_ACK, 1, 517 last_idx); 518 519 /* We updated the rate scale win -- if its been more than 520 * flush_time since the last run, schedule the flush 521 * again */ 522 spin_lock_irqsave(&rs_sta->lock, flags); 523 524 if (!rs_sta->flush_pending && 525 time_after(jiffies, rs_sta->last_flush + rs_sta->flush_time)) { 526 527 rs_sta->last_partial_flush = jiffies; 528 rs_sta->flush_pending = 1; 529 mod_timer(&rs_sta->rate_scale_flush, 530 jiffies + rs_sta->flush_time); 531 } 532 533 spin_unlock_irqrestore(&rs_sta->lock, flags); 534 535 D_RATE("leave\n"); 536 } 537 538 static u16 539 il3945_get_adjacent_rate(struct il3945_rs_sta *rs_sta, u8 idx, u16 rate_mask, 540 enum nl80211_band band) 541 { 542 u8 high = RATE_INVALID; 543 u8 low = RATE_INVALID; 544 struct il_priv *il __maybe_unused = rs_sta->il; 545 546 /* 802.11A walks to the next literal adjacent rate in 547 * the rate table */ 548 if (unlikely(band == NL80211_BAND_5GHZ)) { 549 int i; 550 u32 mask; 551 552 /* Find the previous rate that is in the rate mask */ 553 i = idx - 1; 554 for (mask = (1 << i); i >= 0; i--, mask >>= 1) { 555 if (rate_mask & mask) { 556 low = i; 557 break; 558 } 559 } 560 561 /* Find the next rate that is in the rate mask */ 562 i = idx + 1; 563 for (mask = (1 << i); i < RATE_COUNT_3945; i++, mask <<= 1) { 564 if (rate_mask & mask) { 565 high = i; 566 break; 567 } 568 } 569 570 return (high << 8) | low; 571 } 572 573 low = idx; 574 while (low != RATE_INVALID) { 575 if (rs_sta->tgg) 576 low = il3945_rates[low].prev_rs_tgg; 577 else 578 low = il3945_rates[low].prev_rs; 579 if (low == RATE_INVALID) 580 break; 581 if (rate_mask & (1 << low)) 582 break; 583 D_RATE("Skipping masked lower rate: %d\n", low); 584 } 585 586 high = idx; 587 while (high != RATE_INVALID) { 588 if (rs_sta->tgg) 589 high = il3945_rates[high].next_rs_tgg; 590 else 591 high = il3945_rates[high].next_rs; 592 if (high == RATE_INVALID) 593 break; 594 if (rate_mask & (1 << high)) 595 break; 596 D_RATE("Skipping masked higher rate: %d\n", high); 597 } 598 599 return (high << 8) | low; 600 } 601 602 /** 603 * il3945_rs_get_rate - find the rate for the requested packet 604 * 605 * Returns the ieee80211_rate structure allocated by the driver. 606 * 607 * The rate control algorithm has no internal mapping between hw_mode's 608 * rate ordering and the rate ordering used by the rate control algorithm. 609 * 610 * The rate control algorithm uses a single table of rates that goes across 611 * the entire A/B/G spectrum vs. being limited to just one particular 612 * hw_mode. 613 * 614 * As such, we can't convert the idx obtained below into the hw_mode's 615 * rate table and must reference the driver allocated rate table 616 * 617 */ 618 static void 619 il3945_rs_get_rate(void *il_r, struct ieee80211_sta *sta, void *il_sta, 620 struct ieee80211_tx_rate_control *txrc) 621 { 622 struct ieee80211_supported_band *sband = txrc->sband; 623 struct sk_buff *skb = txrc->skb; 624 u8 low = RATE_INVALID; 625 u8 high = RATE_INVALID; 626 u16 high_low; 627 int idx; 628 struct il3945_rs_sta *rs_sta = il_sta; 629 struct il3945_rate_scale_data *win = NULL; 630 int current_tpt = IL_INVALID_VALUE; 631 int low_tpt = IL_INVALID_VALUE; 632 int high_tpt = IL_INVALID_VALUE; 633 u32 fail_count; 634 s8 scale_action = 0; 635 unsigned long flags; 636 u16 rate_mask; 637 s8 max_rate_idx = -1; 638 struct il_priv *il __maybe_unused = (struct il_priv *)il_r; 639 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 640 641 D_RATE("enter\n"); 642 643 /* Treat uninitialized rate scaling data same as non-existing. */ 644 if (rs_sta && !rs_sta->il) { 645 D_RATE("Rate scaling information not initialized yet.\n"); 646 il_sta = NULL; 647 } 648 649 if (rate_control_send_low(sta, il_sta, txrc)) 650 return; 651 652 rate_mask = sta->supp_rates[sband->band]; 653 654 /* get user max rate if set */ 655 max_rate_idx = fls(txrc->rate_idx_mask) - 1; 656 if (sband->band == NL80211_BAND_5GHZ && max_rate_idx != -1) 657 max_rate_idx += IL_FIRST_OFDM_RATE; 658 if (max_rate_idx < 0 || max_rate_idx >= RATE_COUNT) 659 max_rate_idx = -1; 660 661 idx = min(rs_sta->last_txrate_idx & 0xffff, RATE_COUNT_3945 - 1); 662 663 if (sband->band == NL80211_BAND_5GHZ) 664 rate_mask = rate_mask << IL_FIRST_OFDM_RATE; 665 666 spin_lock_irqsave(&rs_sta->lock, flags); 667 668 /* for recent assoc, choose best rate regarding 669 * to rssi value 670 */ 671 if (rs_sta->start_rate != RATE_INVALID) { 672 if (rs_sta->start_rate < idx && 673 (rate_mask & (1 << rs_sta->start_rate))) 674 idx = rs_sta->start_rate; 675 rs_sta->start_rate = RATE_INVALID; 676 } 677 678 /* force user max rate if set by user */ 679 if (max_rate_idx != -1 && max_rate_idx < idx) { 680 if (rate_mask & (1 << max_rate_idx)) 681 idx = max_rate_idx; 682 } 683 684 win = &(rs_sta->win[idx]); 685 686 fail_count = win->counter - win->success_counter; 687 688 if (fail_count < RATE_MIN_FAILURE_TH && 689 win->success_counter < RATE_MIN_SUCCESS_TH) { 690 spin_unlock_irqrestore(&rs_sta->lock, flags); 691 692 D_RATE("Invalid average_tpt on rate %d: " 693 "counter: %d, success_counter: %d, " 694 "expected_tpt is %sNULL\n", idx, win->counter, 695 win->success_counter, 696 rs_sta->expected_tpt ? "not " : ""); 697 698 /* Can't calculate this yet; not enough history */ 699 win->average_tpt = IL_INVALID_VALUE; 700 goto out; 701 702 } 703 704 current_tpt = win->average_tpt; 705 706 high_low = 707 il3945_get_adjacent_rate(rs_sta, idx, rate_mask, sband->band); 708 low = high_low & 0xff; 709 high = (high_low >> 8) & 0xff; 710 711 /* If user set max rate, dont allow higher than user constrain */ 712 if (max_rate_idx != -1 && max_rate_idx < high) 713 high = RATE_INVALID; 714 715 /* Collect Measured throughputs of adjacent rates */ 716 if (low != RATE_INVALID) 717 low_tpt = rs_sta->win[low].average_tpt; 718 719 if (high != RATE_INVALID) 720 high_tpt = rs_sta->win[high].average_tpt; 721 722 spin_unlock_irqrestore(&rs_sta->lock, flags); 723 724 scale_action = 0; 725 726 /* Low success ratio , need to drop the rate */ 727 if (win->success_ratio < RATE_DECREASE_TH || !current_tpt) { 728 D_RATE("decrease rate because of low success_ratio\n"); 729 scale_action = -1; 730 /* No throughput measured yet for adjacent rates, 731 * try increase */ 732 } else if (low_tpt == IL_INVALID_VALUE && high_tpt == IL_INVALID_VALUE) { 733 734 if (high != RATE_INVALID && 735 win->success_ratio >= RATE_INCREASE_TH) 736 scale_action = 1; 737 else if (low != RATE_INVALID) 738 scale_action = 0; 739 740 /* Both adjacent throughputs are measured, but neither one has 741 * better throughput; we're using the best rate, don't change 742 * it! */ 743 } else if (low_tpt != IL_INVALID_VALUE && high_tpt != IL_INVALID_VALUE 744 && low_tpt < current_tpt && high_tpt < current_tpt) { 745 746 D_RATE("No action -- low [%d] & high [%d] < " 747 "current_tpt [%d]\n", low_tpt, high_tpt, current_tpt); 748 scale_action = 0; 749 750 /* At least one of the rates has better throughput */ 751 } else { 752 if (high_tpt != IL_INVALID_VALUE) { 753 754 /* High rate has better throughput, Increase 755 * rate */ 756 if (high_tpt > current_tpt && 757 win->success_ratio >= RATE_INCREASE_TH) 758 scale_action = 1; 759 else { 760 D_RATE("decrease rate because of high tpt\n"); 761 scale_action = 0; 762 } 763 } else if (low_tpt != IL_INVALID_VALUE) { 764 if (low_tpt > current_tpt) { 765 D_RATE("decrease rate because of low tpt\n"); 766 scale_action = -1; 767 } else if (win->success_ratio >= RATE_INCREASE_TH) { 768 /* Lower rate has better 769 * throughput,decrease rate */ 770 scale_action = 1; 771 } 772 } 773 } 774 775 /* Sanity check; asked for decrease, but success rate or throughput 776 * has been good at old rate. Don't change it. */ 777 if (scale_action == -1 && low != RATE_INVALID && 778 (win->success_ratio > RATE_HIGH_TH || 779 current_tpt > 100 * rs_sta->expected_tpt[low])) 780 scale_action = 0; 781 782 switch (scale_action) { 783 case -1: 784 /* Decrese rate */ 785 if (low != RATE_INVALID) 786 idx = low; 787 break; 788 case 1: 789 /* Increase rate */ 790 if (high != RATE_INVALID) 791 idx = high; 792 793 break; 794 case 0: 795 default: 796 /* No change */ 797 break; 798 } 799 800 D_RATE("Selected %d (action %d) - low %d high %d\n", idx, scale_action, 801 low, high); 802 803 out: 804 805 if (sband->band == NL80211_BAND_5GHZ) { 806 if (WARN_ON_ONCE(idx < IL_FIRST_OFDM_RATE)) 807 idx = IL_FIRST_OFDM_RATE; 808 rs_sta->last_txrate_idx = idx; 809 info->control.rates[0].idx = idx - IL_FIRST_OFDM_RATE; 810 } else { 811 rs_sta->last_txrate_idx = idx; 812 info->control.rates[0].idx = rs_sta->last_txrate_idx; 813 } 814 info->control.rates[0].count = 1; 815 816 D_RATE("leave: %d\n", idx); 817 } 818 819 #ifdef CONFIG_MAC80211_DEBUGFS 820 821 static ssize_t 822 il3945_sta_dbgfs_stats_table_read(struct file *file, char __user *user_buf, 823 size_t count, loff_t *ppos) 824 { 825 char *buff; 826 int desc = 0; 827 int j; 828 ssize_t ret; 829 struct il3945_rs_sta *lq_sta = file->private_data; 830 831 buff = kmalloc(1024, GFP_KERNEL); 832 if (!buff) 833 return -ENOMEM; 834 835 desc += 836 sprintf(buff + desc, 837 "tx packets=%d last rate idx=%d\n" 838 "rate=0x%X flush time %d\n", lq_sta->tx_packets, 839 lq_sta->last_txrate_idx, lq_sta->start_rate, 840 jiffies_to_msecs(lq_sta->flush_time)); 841 for (j = 0; j < RATE_COUNT_3945; j++) { 842 desc += 843 sprintf(buff + desc, "counter=%d success=%d %%=%d\n", 844 lq_sta->win[j].counter, 845 lq_sta->win[j].success_counter, 846 lq_sta->win[j].success_ratio); 847 } 848 ret = simple_read_from_buffer(user_buf, count, ppos, buff, desc); 849 kfree(buff); 850 return ret; 851 } 852 853 static const struct file_operations rs_sta_dbgfs_stats_table_ops = { 854 .read = il3945_sta_dbgfs_stats_table_read, 855 .open = simple_open, 856 .llseek = default_llseek, 857 }; 858 859 static void 860 il3945_add_debugfs(void *il, void *il_sta, struct dentry *dir) 861 { 862 struct il3945_rs_sta *lq_sta = il_sta; 863 864 lq_sta->rs_sta_dbgfs_stats_table_file = 865 debugfs_create_file("rate_stats_table", 0600, dir, lq_sta, 866 &rs_sta_dbgfs_stats_table_ops); 867 868 } 869 870 static void 871 il3945_remove_debugfs(void *il, void *il_sta) 872 { 873 struct il3945_rs_sta *lq_sta = il_sta; 874 debugfs_remove(lq_sta->rs_sta_dbgfs_stats_table_file); 875 } 876 #endif 877 878 /* 879 * Initialization of rate scaling information is done by driver after 880 * the station is added. Since mac80211 calls this function before a 881 * station is added we ignore it. 882 */ 883 static void 884 il3945_rs_rate_init_stub(void *il_r, struct ieee80211_supported_band *sband, 885 struct cfg80211_chan_def *chandef, 886 struct ieee80211_sta *sta, void *il_sta) 887 { 888 } 889 890 static const struct rate_control_ops rs_ops = { 891 .name = RS_NAME, 892 .tx_status = il3945_rs_tx_status, 893 .get_rate = il3945_rs_get_rate, 894 .rate_init = il3945_rs_rate_init_stub, 895 .alloc = il3945_rs_alloc, 896 .free = il3945_rs_free, 897 .alloc_sta = il3945_rs_alloc_sta, 898 .free_sta = il3945_rs_free_sta, 899 #ifdef CONFIG_MAC80211_DEBUGFS 900 .add_sta_debugfs = il3945_add_debugfs, 901 .remove_sta_debugfs = il3945_remove_debugfs, 902 #endif 903 904 }; 905 906 void 907 il3945_rate_scale_init(struct ieee80211_hw *hw, s32 sta_id) 908 { 909 struct il_priv *il = hw->priv; 910 s32 rssi = 0; 911 unsigned long flags; 912 struct il3945_rs_sta *rs_sta; 913 struct ieee80211_sta *sta; 914 struct il3945_sta_priv *psta; 915 916 D_RATE("enter\n"); 917 918 rcu_read_lock(); 919 920 sta = ieee80211_find_sta(il->vif, il->stations[sta_id].sta.sta.addr); 921 if (!sta) { 922 D_RATE("Unable to find station to initialize rate scaling.\n"); 923 rcu_read_unlock(); 924 return; 925 } 926 927 psta = (void *)sta->drv_priv; 928 rs_sta = &psta->rs_sta; 929 930 spin_lock_irqsave(&rs_sta->lock, flags); 931 932 rs_sta->tgg = 0; 933 switch (il->band) { 934 case NL80211_BAND_2GHZ: 935 /* TODO: this always does G, not a regression */ 936 if (il->active.flags & RXON_FLG_TGG_PROTECT_MSK) { 937 rs_sta->tgg = 1; 938 rs_sta->expected_tpt = il3945_expected_tpt_g_prot; 939 } else 940 rs_sta->expected_tpt = il3945_expected_tpt_g; 941 break; 942 case NL80211_BAND_5GHZ: 943 rs_sta->expected_tpt = il3945_expected_tpt_a; 944 break; 945 default: 946 BUG(); 947 break; 948 } 949 950 spin_unlock_irqrestore(&rs_sta->lock, flags); 951 952 rssi = il->_3945.last_rx_rssi; 953 if (rssi == 0) 954 rssi = IL_MIN_RSSI_VAL; 955 956 D_RATE("Network RSSI: %d\n", rssi); 957 958 rs_sta->start_rate = il3945_get_rate_idx_by_rssi(rssi, il->band); 959 960 D_RATE("leave: rssi %d assign rate idx: " "%d (plcp 0x%x)\n", rssi, 961 rs_sta->start_rate, il3945_rates[rs_sta->start_rate].plcp); 962 rcu_read_unlock(); 963 } 964 965 int 966 il3945_rate_control_register(void) 967 { 968 return ieee80211_rate_control_register(&rs_ops); 969 } 970 971 void 972 il3945_rate_control_unregister(void) 973 { 974 ieee80211_rate_control_unregister(&rs_ops); 975 } 976