drivers/net/wireless/iwlwifi/iwl-3945-rs.c

   1 /******************************************************************************
   2  *
   3  * Copyright(c) 2005 - 2007 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  * James P. Ketrenos <ipw2100-admin@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/wireless.h>
  31 #include <net/mac80211.h>
  32 #include <net/ieee80211.h>
  33
  34 #include <linux/netdevice.h>
  35 #include <linux/etherdevice.h>
  36 #include <linux/delay.h>
  37
  38 #include <linux/workqueue.h>
  39
  40 #include <net/mac80211.h>
  41 #include <linux/wireless.h>
  42
  43 #define IWL 3945
  44
  45 #include "../net/mac80211/ieee80211_rate.h"
  46
  47 #include "iwlwifi.h"
  48
  49 #define RS_NAME "iwl-3945-rs"
  50
  51 struct iwl_rate_scale_data {
  52         u64 data;
  53         s32 success_counter;
  54         s32 success_ratio;
  55         s32 counter;
  56         s32 average_tpt;
  57         unsigned long stamp;
  58 };
  59
  60 struct iwl_rate_scale_priv {
  61         spinlock_t lock;
  62         s32 *expected_tpt;
  63         unsigned long last_partial_flush;
  64         unsigned long last_flush;
  65         u32 flush_time;
  66         u32 last_tx_packets;
  67         u32 tx_packets;
  68         u8 tgg;
  69         u8 flush_pending;
  70         u8 start_rate;
  71         u8 ibss_sta_added;
  72         struct timer_list rate_scale_flush;
  73         struct iwl_rate_scale_data win[IWL_RATE_COUNT];
  74 };
  75
  76 static s32 iwl_expected_tpt_g[IWL_RATE_COUNT] = {
  77         0, 0, 76, 104, 130, 168, 191, 202, 7, 13, 35, 58
  78 };
  79
  80 static s32 iwl_expected_tpt_g_prot[IWL_RATE_COUNT] = {
  81         0, 0, 0, 80, 93, 113, 123, 125, 7, 13, 35, 58
  82 };
  83
  84 static s32 iwl_expected_tpt_a[IWL_RATE_COUNT] = {
  85         40, 57, 72, 98, 121, 154, 177, 186, 0, 0, 0, 0
  86 };
  87
  88 static s32 iwl_expected_tpt_b[IWL_RATE_COUNT] = {
  89         0, 0, 0, 0, 0, 0, 0, 0, 7, 13, 35, 58
  90 };
  91
  92 struct iwl_tpt_entry {
  93         s8 min_rssi;
  94         u8 index;
  95 };
  96
  97 static struct iwl_tpt_entry iwl_tpt_table_a[] = {
  98         {-60, IWL_RATE_54M_INDEX},
  99         {-64, IWL_RATE_48M_INDEX},
 100         {-72, IWL_RATE_36M_INDEX},
 101         {-80, IWL_RATE_24M_INDEX},
 102         {-84, IWL_RATE_18M_INDEX},
 103         {-85, IWL_RATE_12M_INDEX},
 104         {-87, IWL_RATE_9M_INDEX},
 105         {-89, IWL_RATE_6M_INDEX}
 106 };
 107
 108 static struct iwl_tpt_entry iwl_tpt_table_b[] = {
 109         {-86, IWL_RATE_11M_INDEX},
 110         {-88, IWL_RATE_5M_INDEX},
 111         {-90, IWL_RATE_2M_INDEX},
 112         {-92, IWL_RATE_1M_INDEX}
 113
 114 };
 115
 116 static struct iwl_tpt_entry iwl_tpt_table_g[] = {
 117         {-60, IWL_RATE_54M_INDEX},
 118         {-64, IWL_RATE_48M_INDEX},
 119         {-68, IWL_RATE_36M_INDEX},
 120         {-80, IWL_RATE_24M_INDEX},
 121         {-84, IWL_RATE_18M_INDEX},
 122         {-85, IWL_RATE_12M_INDEX},
 123         {-86, IWL_RATE_11M_INDEX},
 124         {-88, IWL_RATE_5M_INDEX},
 125         {-90, IWL_RATE_2M_INDEX},
 126         {-92, IWL_RATE_1M_INDEX}
 127 };
 128
 129 #define IWL_RATE_MAX_WINDOW          62
 130 #define IWL_RATE_FLUSH        (3*HZ/10)
 131 #define IWL_RATE_WIN_FLUSH       (HZ/2)
 132 #define IWL_RATE_HIGH_TH          11520
 133 #define IWL_RATE_MIN_FAILURE_TH       8
 134 #define IWL_RATE_MIN_SUCCESS_TH       8
 135 #define IWL_RATE_DECREASE_TH       1920
 136
 137 static u8 iwl_get_rate_index_by_rssi(s32 rssi, u8 mode)
 138 {
 139         u32 index = 0;
 140         u32 table_size = 0;
 141         struct iwl_tpt_entry *tpt_table = NULL;
 142
 143         if ((rssi < IWL_MIN_RSSI_VAL) || (rssi > IWL_MAX_RSSI_VAL))
 144                 rssi = IWL_MIN_RSSI_VAL;
 145
 146         switch (mode) {
 147         case MODE_IEEE80211G:
 148                 tpt_table = iwl_tpt_table_g;
 149                 table_size = ARRAY_SIZE(iwl_tpt_table_g);
 150                 break;
 151
 152         case MODE_IEEE80211A:
 153                 tpt_table = iwl_tpt_table_a;
 154                 table_size = ARRAY_SIZE(iwl_tpt_table_a);
 155                 break;
 156
 157         default:
 158         case MODE_IEEE80211B:
 159                 tpt_table = iwl_tpt_table_b;
 160                 table_size = ARRAY_SIZE(iwl_tpt_table_b);
 161                 break;
 162         }
 163
 164         while ((index < table_size) && (rssi < tpt_table[index].min_rssi))
 165                 index++;
 166
 167         index = min(index, (table_size - 1));
 168
 169         return tpt_table[index].index;
 170 }
 171
 172 static void iwl_clear_window(struct iwl_rate_scale_data *window)
 173 {
 174         window->data = 0;
 175         window->success_counter = 0;
 176         window->success_ratio = IWL_INVALID_VALUE;
 177         window->counter = 0;
 178         window->average_tpt = IWL_INVALID_VALUE;
 179         window->stamp = 0;
 180 }
 181
 182 /**
 183  * iwl_rate_scale_flush_windows - flush out the rate scale windows
 184  *
 185  * Returns the number of windows that have gathered data but were
 186  * not flushed.  If there were any that were not flushed, then
 187  * reschedule the rate flushing routine.
 188  */
 189 static int iwl_rate_scale_flush_windows(struct iwl_rate_scale_priv *rs_priv)
 190 {
 191         int unflushed = 0;
 192         int i;
 193         unsigned long flags;
 194
 195         /*
 196          * For each rate, if we have collected data on that rate
 197          * and it has been more than IWL_RATE_WIN_FLUSH
 198          * since we flushed, clear out the gathered statistics
 199          */
 200         for (i = 0; i < IWL_RATE_COUNT; i++) {
 201                 if (!rs_priv->win[i].counter)
 202                         continue;
 203
 204                 spin_lock_irqsave(&rs_priv->lock, flags);
 205                 if (time_after(jiffies, rs_priv->win[i].stamp +
 206                                IWL_RATE_WIN_FLUSH)) {
 207                         IWL_DEBUG_RATE("flushing %d samples of rate "
 208                                        "index %d\n",
 209                                        rs_priv->win[i].counter, i);
 210                         iwl_clear_window(&rs_priv->win[i]);
 211                 } else
 212                         unflushed++;
 213                 spin_unlock_irqrestore(&rs_priv->lock, flags);
 214         }
 215
 216         return unflushed;
 217 }
 218
 219 #define IWL_RATE_FLUSH_MAX              5000    /* msec */
 220 #define IWL_RATE_FLUSH_MIN              50      /* msec */
 221
 222 static void iwl_bg_rate_scale_flush(unsigned long data)
 223 {
 224         struct iwl_rate_scale_priv *rs_priv = (void *)data;
 225         int unflushed = 0;
 226         unsigned long flags;
 227         u32 packet_count, duration, pps;
 228
 229         IWL_DEBUG_RATE("enter\n");
 230
 231         unflushed = iwl_rate_scale_flush_windows(rs_priv);
 232
 233         spin_lock_irqsave(&rs_priv->lock, flags);
 234
 235         rs_priv->flush_pending = 0;
 236
 237         /* Number of packets Rx'd since last time this timer ran */
 238         packet_count = (rs_priv->tx_packets - rs_priv->last_tx_packets) + 1;
 239
 240         rs_priv->last_tx_packets = rs_priv->tx_packets + 1;
 241
 242         if (unflushed) {
 243                 duration =
 244                     jiffies_to_msecs(jiffies - rs_priv->last_partial_flush);
 245 /*              duration = jiffies_to_msecs(rs_priv->flush_time); */
 246
 247                 IWL_DEBUG_RATE("Tx'd %d packets in %dms\n",
 248                                packet_count, duration);
 249
 250                 /* Determine packets per second */
 251                 if (duration)
 252                         pps = (packet_count * 1000) / duration;
 253                 else
 254                         pps = 0;
 255
 256                 if (pps) {
 257                         duration = IWL_RATE_FLUSH_MAX / pps;
 258                         if (duration < IWL_RATE_FLUSH_MIN)
 259                                 duration = IWL_RATE_FLUSH_MIN;
 260                 } else
 261                         duration = IWL_RATE_FLUSH_MAX;
 262
 263                 rs_priv->flush_time = msecs_to_jiffies(duration);
 264
 265                 IWL_DEBUG_RATE("new flush period: %d msec ave %d\n",
 266                                duration, packet_count);
 267
 268                 mod_timer(&rs_priv->rate_scale_flush, jiffies +
 269                           rs_priv->flush_time);
 270
 271                 rs_priv->last_partial_flush = jiffies;
 272         }
 273
 274         /* If there weren't any unflushed entries, we don't schedule the timer
 275          * to run again */
 276
 277         rs_priv->last_flush = jiffies;
 278
 279         spin_unlock_irqrestore(&rs_priv->lock, flags);
 280
 281         IWL_DEBUG_RATE("leave\n");
 282 }
 283
 284 /**
 285  * iwl_collect_tx_data - Update the success/failure sliding window
 286  *
 287  * We keep a sliding window of the last 64 packets transmitted
 288  * at this rate.  window->data contains the bitmask of successful
 289  * packets.
 290  */
 291 static void iwl_collect_tx_data(struct iwl_rate_scale_priv *rs_priv,
 292                                 struct iwl_rate_scale_data *window,
 293                                 int success, int retries)
 294 {
 295         unsigned long flags;
 296
 297         if (!retries) {
 298                 IWL_DEBUG_RATE("leave: retries == 0 -- should be at least 1\n");
 299                 return;
 300         }
 301
 302         while (retries--) {
 303                 spin_lock_irqsave(&rs_priv->lock, flags);
 304
 305                 /* If we have filled up the window then subtract one from the
 306                  * success counter if the high-bit is counting toward
 307                  * success */
 308                 if (window->counter == IWL_RATE_MAX_WINDOW) {
 309                         if (window->data & (1ULL << (IWL_RATE_MAX_WINDOW - 1)))
 310                                 window->success_counter--;
 311                 } else
 312                         window->counter++;
 313
 314                 /* Slide the window to the left one bit */
 315                 window->data = (window->data << 1);
 316
 317                 /* If this packet was a success then set the low bit high */
 318                 if (success) {
 319                         window->success_counter++;
 320                         window->data |= 1;
 321                 }
 322
 323                 /* window->counter can't be 0 -- it is either >0 or
 324                  * IWL_RATE_MAX_WINDOW */
 325                 window->success_ratio = 12800 * window->success_counter /
 326                     window->counter;
 327
 328                 /* Tag this window as having been updated */
 329                 window->stamp = jiffies;
 330
 331                 spin_unlock_irqrestore(&rs_priv->lock, flags);
 332         }
 333 }
 334
 335 static void rs_rate_init(void *priv_rate, void *priv_sta,
 336                          struct ieee80211_local *local, struct sta_info *sta)
 337 {
 338         int i;
 339
 340         IWL_DEBUG_RATE("enter\n");
 341
 342         /* TODO: what is a good starting rate for STA? About middle? Maybe not
 343          * the lowest or the highest rate.. Could consider using RSSI from
 344          * previous packets? Need to have IEEE 802.1X auth succeed immediately
 345          * after assoc.. */
 346
 347         for (i = IWL_RATE_COUNT - 1; i >= 0; i--) {
 348                 if (sta->supp_rates & (1 << i)) {
 349                         sta->txrate = i;
 350                         break;
 351                 }
 352         }
 353
 354         sta->last_txrate = sta->txrate;
 355
 356         IWL_DEBUG_RATE("leave\n");
 357 }
 358
 359 static void *rs_alloc(struct ieee80211_local *local)
 360 {
 361         return local->hw.priv;
 362 }
 363
 364 /* rate scale requires free function to be implmented */
 365 static void rs_free(void *priv)
 366 {
 367         return;
 368 }
 369 static void rs_clear(void *priv)
 370 {
 371         return;
 372 }
 373
 374
 375 static void *rs_alloc_sta(void *priv, gfp_t gfp)
 376 {
 377         struct iwl_rate_scale_priv *rs_priv;
 378         int i;
 379
 380         IWL_DEBUG_RATE("enter\n");
 381
 382         rs_priv = kzalloc(sizeof(struct iwl_rate_scale_priv), gfp);
 383         if (!rs_priv) {
 384                 IWL_DEBUG_RATE("leave: ENOMEM\n");
 385                 return NULL;
 386         }
 387
 388         spin_lock_init(&rs_priv->lock);
 389
 390         rs_priv->start_rate = IWL_RATE_INVALID;
 391
 392         /* default to just 802.11b */
 393         rs_priv->expected_tpt = iwl_expected_tpt_b;
 394
 395         rs_priv->last_partial_flush = jiffies;
 396         rs_priv->last_flush = jiffies;
 397         rs_priv->flush_time = IWL_RATE_FLUSH;
 398         rs_priv->last_tx_packets = 0;
 399         rs_priv->ibss_sta_added = 0;
 400
 401         init_timer(&rs_priv->rate_scale_flush);
 402         rs_priv->rate_scale_flush.data = (unsigned long)rs_priv;
 403         rs_priv->rate_scale_flush.function = &iwl_bg_rate_scale_flush;
 404
 405         for (i = 0; i < IWL_RATE_COUNT; i++)
 406                 iwl_clear_window(&rs_priv->win[i]);
 407
 408         IWL_DEBUG_RATE("leave\n");
 409
 410         return rs_priv;
 411 }
 412
 413 static void rs_free_sta(void *priv, void *priv_sta)
 414 {
 415         struct iwl_rate_scale_priv *rs_priv = priv_sta;
 416
 417         IWL_DEBUG_RATE("enter\n");
 418         del_timer_sync(&rs_priv->rate_scale_flush);
 419         kfree(rs_priv);
 420         IWL_DEBUG_RATE("leave\n");
 421 }
 422
 423 /**
 424  * rs_tx_status - Update rate control values based on Tx results
 425  *
 426  * NOTE: Uses iwl_priv->retry_rate for the # of retries attempted by
 427  * the hardware for each rate.
 428  */
 429 static void rs_tx_status(void *priv_rate,
 430                          struct net_device *dev,
 431                          struct sk_buff *skb,
 432                          struct ieee80211_tx_status *tx_resp)
 433 {
 434         u8 retries, current_count;
 435         int scale_rate_index, first_index, last_index;
 436         unsigned long flags;
 437         struct sta_info *sta;
 438         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 439         struct iwl_priv *priv = (struct iwl_priv *)priv_rate;
 440         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
 441         struct iwl_rate_scale_priv *rs_priv;
 442
 443         IWL_DEBUG_RATE("enter\n");
 444
 445         retries = tx_resp->retry_count;
 446
 447         first_index = tx_resp->control.tx_rate;
 448         if ((first_index < 0) || (first_index >= IWL_RATE_COUNT)) {
 449                 IWL_DEBUG_RATE("leave: Rate out of bounds: %0x for %d\n",
 450                                tx_resp->control.tx_rate, first_index);
 451                 return;
 452         }
 453
 454         sta = sta_info_get(local, hdr->addr1);
 455         if (!sta || !sta->rate_ctrl_priv) {
 456                 if (sta)
 457                         sta_info_put(sta);
 458                 IWL_DEBUG_RATE("leave: No STA priv data to update!\n");
 459                 return;
 460         }
 461
 462         rs_priv = (void *)sta->rate_ctrl_priv;
 463
 464         rs_priv->tx_packets++;
 465
 466         scale_rate_index = first_index;
 467         last_index = first_index;
 468
 469         /*
 470          * Update the window for each rate.  We determine which rates
 471          * were Tx'd based on the total number of retries vs. the number
 472          * of retries configured for each rate -- currently set to the
 473          * priv value 'retry_rate' vs. rate specific
 474          *
 475          * On exit from this while loop last_index indicates the rate
 476          * at which the frame was finally transmitted (or failed if no
 477          * ACK)
 478          */
 479         while (retries > 0) {
 480                 if (retries < priv->retry_rate) {
 481                         current_count = retries;
 482                         last_index = scale_rate_index;
 483                 } else {
 484                         current_count = priv->retry_rate;
 485                         last_index = iwl_get_prev_ieee_rate(scale_rate_index);
 486                 }
 487
 488                 /* Update this rate accounting for as many retries
 489                  * as was used for it (per current_count) */
 490                 iwl_collect_tx_data(rs_priv,
 491                                     &rs_priv->win[scale_rate_index],
 492                                     0, current_count);
 493                 IWL_DEBUG_RATE("Update rate %d for %d retries.\n",
 494                                scale_rate_index, current_count);
 495
 496                 retries -= current_count;
 497
 498                 if (retries)
 499                         scale_rate_index =
 500                             iwl_get_prev_ieee_rate(scale_rate_index);
 501         }
 502
 503         /* Update the last index window with success/failure based on ACK */
 504         IWL_DEBUG_RATE("Update rate %d with %s.\n",
 505                        last_index,
 506                        (tx_resp->flags & IEEE80211_TX_STATUS_ACK) ?
 507                        "success" : "failure");
 508         iwl_collect_tx_data(rs_priv,
 509                             &rs_priv->win[last_index],
 510                             tx_resp->flags & IEEE80211_TX_STATUS_ACK, 1);
 511
 512         /* We updated the rate scale window -- if its been more than
 513          * flush_time since the last run, schedule the flush
 514          * again */
 515         spin_lock_irqsave(&rs_priv->lock, flags);
 516
 517         if (!rs_priv->flush_pending &&
 518             time_after(jiffies, rs_priv->last_partial_flush +
 519                        rs_priv->flush_time)) {
 520
 521                 rs_priv->flush_pending = 1;
 522                 mod_timer(&rs_priv->rate_scale_flush,
 523                           jiffies + rs_priv->flush_time);
 524         }
 525
 526         spin_unlock_irqrestore(&rs_priv->lock, flags);
 527
 528         sta_info_put(sta);
 529
 530         IWL_DEBUG_RATE("leave\n");
 531
 532         return;
 533 }
 534
 535 static struct ieee80211_rate *iwl_get_lowest_rate(struct ieee80211_local
 536                                                   *local)
 537 {
 538         struct ieee80211_hw_mode *mode = local->oper_hw_mode;
 539         int i;
 540
 541         for (i = 0; i < mode->num_rates; i++) {
 542                 struct ieee80211_rate *rate = &mode->rates[i];
 543
 544                 if (rate->flags & IEEE80211_RATE_SUPPORTED)
 545                         return rate;
 546         }
 547
 548         return &mode->rates[0];
 549 }
 550
 551 static u16 iwl_get_adjacent_rate(struct iwl_rate_scale_priv *rs_priv,
 552                                  u8 index, u16 rate_mask, int phymode)
 553 {
 554         u8 high = IWL_RATE_INVALID;
 555         u8 low = IWL_RATE_INVALID;
 556
 557         /* 802.11A walks to the next literal adjascent rate in
 558          * the rate table */
 559         if (unlikely(phymode == MODE_IEEE80211A)) {
 560                 int i;
 561                 u32 mask;
 562
 563                 /* Find the previous rate that is in the rate mask */
 564                 i = index - 1;
 565                 for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
 566                         if (rate_mask & mask) {
 567                                 low = i;
 568                                 break;
 569                         }
 570                 }
 571
 572                 /* Find the next rate that is in the rate mask */
 573                 i = index + 1;
 574                 for (mask = (1 << i); i < IWL_RATE_COUNT; i++, mask <<= 1) {
 575                         if (rate_mask & mask) {
 576                                 high = i;
 577                                 break;
 578                         }
 579                 }
 580
 581                 return (high << 8) | low;
 582         }
 583
 584         low = index;
 585         while (low != IWL_RATE_INVALID) {
 586                 if (rs_priv->tgg)
 587                         low = iwl_rates[low].prev_rs_tgg;
 588                 else
 589                         low = iwl_rates[low].prev_rs;
 590                 if (low == IWL_RATE_INVALID)
 591                         break;
 592                 if (rate_mask & (1 << low))
 593                         break;
 594                 IWL_DEBUG_RATE("Skipping masked lower rate: %d\n", low);
 595         }
 596
 597         high = index;
 598         while (high != IWL_RATE_INVALID) {
 599                 if (rs_priv->tgg)
 600                         high = iwl_rates[high].next_rs_tgg;
 601                 else
 602                         high = iwl_rates[high].next_rs;
 603                 if (high == IWL_RATE_INVALID)
 604                         break;
 605                 if (rate_mask & (1 << high))
 606                         break;
 607                 IWL_DEBUG_RATE("Skipping masked higher rate: %d\n", high);
 608         }
 609
 610         return (high << 8) | low;
 611 }
 612
 613 /**
 614  * rs_get_rate - find the rate for the requested packet
 615  *
 616  * Returns the ieee80211_rate structure allocated by the driver.
 617  *
 618  * The rate control algorithm has no internal mapping between hw_mode's
 619  * rate ordering and the rate ordering used by the rate control algorithm.
 620  *
 621  * The rate control algorithm uses a single table of rates that goes across
 622  * the entire A/B/G spectrum vs. being limited to just one particular
 623  * hw_mode.
 624  *
 625  * As such, we can't convert the index obtained below into the hw_mode's
 626  * rate table and must reference the driver allocated rate table
 627  *
 628  */
 629 static struct ieee80211_rate *rs_get_rate(void *priv_rate,
 630                                           struct net_device *dev,
 631                                           struct sk_buff *skb,
 632                                           struct rate_control_extra *extra)
 633 {
 634         u8 low = IWL_RATE_INVALID;
 635         u8 high = IWL_RATE_INVALID;
 636         u16 high_low;
 637         int index;
 638         struct iwl_rate_scale_priv *rs_priv;
 639         struct iwl_rate_scale_data *window = NULL;
 640         int current_tpt = IWL_INVALID_VALUE;
 641         int low_tpt = IWL_INVALID_VALUE;
 642         int high_tpt = IWL_INVALID_VALUE;
 643         u32 fail_count;
 644         s8 scale_action = 0;
 645         unsigned long flags;
 646         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
 647         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 648         struct sta_info *sta;
 649         u16 fc, rate_mask;
 650         struct iwl_priv *priv = (struct iwl_priv *)priv_rate;
 651         DECLARE_MAC_BUF(mac);
 652
 653         IWL_DEBUG_RATE("enter\n");
 654
 655         memset(extra, 0, sizeof(*extra));
 656
 657         fc = le16_to_cpu(hdr->frame_control);
 658         if (((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA) ||
 659             (is_multicast_ether_addr(hdr->addr1))) {
 660                 /* Send management frames and broadcast/multicast data using
 661                  * lowest rate. */
 662                 /* TODO: this could probably be improved.. */
 663                 IWL_DEBUG_RATE("leave: lowest rate (not data or is "
 664                                "multicast)\n");
 665
 666                 return iwl_get_lowest_rate(local);
 667         }
 668
 669         sta = sta_info_get(local, hdr->addr1);
 670         if (!sta || !sta->rate_ctrl_priv) {
 671                 IWL_DEBUG_RATE("leave: No STA priv data to update!\n");
 672                 if (sta)
 673                         sta_info_put(sta);
 674                 return NULL;
 675         }
 676
 677         rate_mask = sta->supp_rates;
 678         index = min(sta->txrate & 0xffff, IWL_RATE_COUNT - 1);
 679
 680         rs_priv = (void *)sta->rate_ctrl_priv;
 681
 682         if ((priv->iw_mode == IEEE80211_IF_TYPE_IBSS) &&
 683             !rs_priv->ibss_sta_added) {
 684                 u8 sta_id = iwl_hw_find_station(priv, hdr->addr1);
 685
 686                 if (sta_id == IWL_INVALID_STATION) {
 687                         IWL_DEBUG_RATE("LQ: ADD station %s\n",
 688                                        print_mac(mac, hdr->addr1));
 689                         sta_id = iwl_add_station(priv,
 690                                     hdr->addr1, 0, CMD_ASYNC);
 691                 }
 692                 if (sta_id != IWL_INVALID_STATION)
 693                         rs_priv->ibss_sta_added = 1;
 694         }
 695
 696         spin_lock_irqsave(&rs_priv->lock, flags);
 697
 698         if (rs_priv->start_rate != IWL_RATE_INVALID) {
 699                 index = rs_priv->start_rate;
 700                 rs_priv->start_rate = IWL_RATE_INVALID;
 701         }
 702
 703         window = &(rs_priv->win[index]);
 704
 705         fail_count = window->counter - window->success_counter;
 706
 707         if (((fail_count <= IWL_RATE_MIN_FAILURE_TH) &&
 708              (window->success_counter < IWL_RATE_MIN_SUCCESS_TH))) {
 709                 window->average_tpt = IWL_INVALID_VALUE;
 710                 spin_unlock_irqrestore(&rs_priv->lock, flags);
 711
 712                 IWL_DEBUG_RATE("Invalid average_tpt on rate %d: "
 713                                "counter: %d, success_counter: %d, "
 714                                "expected_tpt is %sNULL\n",
 715                                index,
 716                                window->counter,
 717                                window->success_counter,
 718                                rs_priv->expected_tpt ? "not " : "");
 719                 goto out;
 720
 721         }
 722
 723         window->average_tpt = ((window->success_ratio *
 724                                 rs_priv->expected_tpt[index] + 64) / 128);
 725         current_tpt = window->average_tpt;
 726
 727         high_low = iwl_get_adjacent_rate(rs_priv, index, rate_mask,
 728                                          local->hw.conf.phymode);
 729         low = high_low & 0xff;
 730         high = (high_low >> 8) & 0xff;
 731
 732         if (low != IWL_RATE_INVALID)
 733                 low_tpt = rs_priv->win[low].average_tpt;
 734
 735         if (high != IWL_RATE_INVALID)
 736                 high_tpt = rs_priv->win[high].average_tpt;
 737
 738         spin_unlock_irqrestore(&rs_priv->lock, flags);
 739
 740         scale_action = 1;
 741
 742         if ((window->success_ratio < IWL_RATE_DECREASE_TH) || !current_tpt) {
 743                 IWL_DEBUG_RATE("decrease rate because of low success_ratio\n");
 744                 scale_action = -1;
 745         } else if ((low_tpt == IWL_INVALID_VALUE) &&
 746                    (high_tpt == IWL_INVALID_VALUE))
 747                 scale_action = 1;
 748         else if ((low_tpt != IWL_INVALID_VALUE) &&
 749                    (high_tpt != IWL_INVALID_VALUE)
 750                    && (low_tpt < current_tpt)
 751                    && (high_tpt < current_tpt)) {
 752                 IWL_DEBUG_RATE("No action -- low [%d] & high [%d] < "
 753                                "current_tpt [%d]\n",
 754                                low_tpt, high_tpt, current_tpt);
 755                 scale_action = 0;
 756         } else {
 757                 if (high_tpt != IWL_INVALID_VALUE) {
 758                         if (high_tpt > current_tpt)
 759                                 scale_action = 1;
 760                         else {
 761                                 IWL_DEBUG_RATE
 762                                     ("decrease rate because of high tpt\n");
 763                                 scale_action = -1;
 764                         }
 765                 } else if (low_tpt != IWL_INVALID_VALUE) {
 766                         if (low_tpt > current_tpt) {
 767                                 IWL_DEBUG_RATE
 768                                     ("decrease rate because of low tpt\n");
 769                                 scale_action = -1;
 770                         } else
 771                                 scale_action = 1;
 772                 }
 773         }
 774
 775         if ((window->success_ratio > IWL_RATE_HIGH_TH) ||
 776             (current_tpt > window->average_tpt)) {
 777                 IWL_DEBUG_RATE("No action -- success_ratio [%d] > HIGH_TH or "
 778                                "current_tpt [%d] > average_tpt [%d]\n",
 779                                window->success_ratio,
 780                                current_tpt, window->average_tpt);
 781                 scale_action = 0;
 782         }
 783
 784         switch (scale_action) {
 785         case -1:
 786                 if (low != IWL_RATE_INVALID)
 787                         index = low;
 788                 break;
 789
 790         case 1:
 791                 if (high != IWL_RATE_INVALID)
 792                         index = high;
 793
 794                 break;
 795
 796         case 0:
 797         default:
 798                 break;
 799         }
 800
 801         IWL_DEBUG_RATE("Selected %d (action %d) - low %d high %d\n",
 802                        index, scale_action, low, high);
 803
 804  out:
 805
 806         sta->last_txrate = index;
 807         sta->txrate = sta->last_txrate;
 808         sta_info_put(sta);
 809
 810         IWL_DEBUG_RATE("leave: %d\n", index);
 811
 812         return &priv->ieee_rates[index];
 813 }
 814
 815 static struct rate_control_ops rs_ops = {
 816         .module = NULL,
 817         .name = RS_NAME,
 818         .tx_status = rs_tx_status,
 819         .get_rate = rs_get_rate,
 820         .rate_init = rs_rate_init,
 821         .clear = rs_clear,
 822         .alloc = rs_alloc,
 823         .free = rs_free,
 824         .alloc_sta = rs_alloc_sta,
 825         .free_sta = rs_free_sta,
 826 };
 827
 828 int iwl_fill_rs_info(struct ieee80211_hw *hw, char *buf, u8 sta_id)
 829 {
 830         struct ieee80211_local *local = hw_to_local(hw);
 831         struct iwl_priv *priv = hw->priv;
 832         struct iwl_rate_scale_priv *rs_priv;
 833         struct sta_info *sta;
 834         unsigned long flags;
 835         int count = 0, i;
 836         u32 samples = 0, success = 0, good = 0;
 837         unsigned long now = jiffies;
 838         u32 max_time = 0;
 839
 840         sta = sta_info_get(local, priv->stations[sta_id].sta.sta.addr);
 841         if (!sta || !sta->rate_ctrl_priv) {
 842                 if (sta) {
 843                         sta_info_put(sta);
 844                         IWL_DEBUG_RATE("leave - no private rate data!\n");
 845                 } else
 846                         IWL_DEBUG_RATE("leave - no station!\n");
 847                 return sprintf(buf, "station %d not found\n", sta_id);
 848         }
 849
 850         rs_priv = (void *)sta->rate_ctrl_priv;
 851         spin_lock_irqsave(&rs_priv->lock, flags);
 852         i = IWL_RATE_54M_INDEX;
 853         while (1) {
 854                 u64 mask;
 855                 int j;
 856
 857                 count +=
 858                     sprintf(&buf[count], " %2dMbs: ", iwl_rates[i].ieee / 2);
 859
 860                 mask = (1ULL << (IWL_RATE_MAX_WINDOW - 1));
 861                 for (j = 0; j < IWL_RATE_MAX_WINDOW; j++, mask >>= 1)
 862                         buf[count++] =
 863                             (rs_priv->win[i].data & mask) ? '1' : '0';
 864
 865                 samples += rs_priv->win[i].counter;
 866                 good += rs_priv->win[i].success_counter;
 867                 success += rs_priv->win[i].success_counter * iwl_rates[i].ieee;
 868
 869                 if (rs_priv->win[i].stamp) {
 870                         int delta =
 871                             jiffies_to_msecs(now - rs_priv->win[i].stamp);
 872
 873                         if (delta > max_time)
 874                                 max_time = delta;
 875
 876                         count += sprintf(&buf[count], "%5dms\n", delta);
 877                 } else
 878                         buf[count++] = '\n';
 879
 880                 j = iwl_get_prev_ieee_rate(i);
 881                 if (j == i)
 882                         break;
 883                 i = j;
 884         }
 885         spin_unlock_irqrestore(&rs_priv->lock, flags);
 886         sta_info_put(sta);
 887
 888         /* Display the average rate of all samples taken.
 889          *
 890          * NOTE:  We multiple # of samples by 2 since the IEEE measurement
 891          * added from iwl_rates is actually 2X the rate */
 892         if (samples)
 893                 count += sprintf(
 894                         &buf[count],
 895                         "\nAverage rate is %3d.%02dMbs over last %4dms\n"
 896                         "%3d%% success (%d good packets over %d tries)\n",
 897                         success / (2 * samples), (success * 5 / samples) % 10,
 898                         max_time, good * 100 / samples, good, samples);
 899         else
 900                 count += sprintf(&buf[count], "\nAverage rate: 0Mbs\n");
 901
 902         return count;
 903 }
 904
 905 void iwl_rate_scale_init(struct ieee80211_hw *hw, s32 sta_id)
 906 {
 907         struct iwl_priv *priv = hw->priv;
 908         s32 rssi = 0;
 909         unsigned long flags;
 910         struct ieee80211_local *local = hw_to_local(hw);
 911         struct iwl_rate_scale_priv *rs_priv;
 912         struct sta_info *sta;
 913
 914         IWL_DEBUG_RATE("enter\n");
 915
 916         if (!local->rate_ctrl->ops->name ||
 917             strcmp(local->rate_ctrl->ops->name, RS_NAME)) {
 918                 IWL_WARNING("iwl-3945-rs not selected as rate control algo!\n");
 919                 IWL_DEBUG_RATE("leave - mac80211 picked the wrong RC algo.\n");
 920                 return;
 921         }
 922
 923         sta = sta_info_get(local, priv->stations[sta_id].sta.sta.addr);
 924         if (!sta || !sta->rate_ctrl_priv) {
 925                 if (sta)
 926                         sta_info_put(sta);
 927                 IWL_DEBUG_RATE("leave - no private rate data!\n");
 928                 return;
 929         }
 930
 931         rs_priv = (void *)sta->rate_ctrl_priv;
 932
 933         spin_lock_irqsave(&rs_priv->lock, flags);
 934
 935         rs_priv->tgg = 0;
 936         switch (priv->phymode) {
 937         case MODE_IEEE80211G:
 938                 if (priv->active_rxon.flags & RXON_FLG_TGG_PROTECT_MSK) {
 939                         rs_priv->tgg = 1;
 940                         rs_priv->expected_tpt = iwl_expected_tpt_g_prot;
 941                 } else
 942                         rs_priv->expected_tpt = iwl_expected_tpt_g;
 943                 break;
 944
 945         case MODE_IEEE80211A:
 946                 rs_priv->expected_tpt = iwl_expected_tpt_a;
 947                 break;
 948
 949         default:
 950                 IWL_WARNING("Invalid phymode.  Defaulting to 802.11b\n");
 951         case MODE_IEEE80211B:
 952                 rs_priv->expected_tpt = iwl_expected_tpt_b;
 953                 break;
 954         }
 955
 956         sta_info_put(sta);
 957         spin_unlock_irqrestore(&rs_priv->lock, flags);
 958
 959         rssi = priv->last_rx_rssi;
 960         if (rssi == 0)
 961                 rssi = IWL_MIN_RSSI_VAL;
 962
 963         IWL_DEBUG(IWL_DL_INFO | IWL_DL_RATE, "Network RSSI: %d\n", rssi);
 964
 965         rs_priv->start_rate = iwl_get_rate_index_by_rssi(rssi, priv->phymode);
 966
 967         IWL_DEBUG_RATE("leave: rssi %d assign rate index: "
 968                        "%d (plcp 0x%x)\n", rssi, rs_priv->start_rate,
 969                        iwl_rates[rs_priv->start_rate].plcp);
 970 }
 971
 972 void iwl_rate_control_register(struct ieee80211_hw *hw)
 973 {
 974         ieee80211_rate_control_register(&rs_ops);
 975 }
 976
 977 void iwl_rate_control_unregister(struct ieee80211_hw *hw)
 978 {
 979         ieee80211_rate_control_unregister(&rs_ops);
 980 }
 981
 982