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/ieee80211_rate.h"
  41
  42 #include "iwl-3945.h"
  43
  44 #define RS_NAME "iwl-3945-rs"
  45
  46 struct iwl3945_rate_scale_data {
  47         u64 data;
  48         s32 success_counter;
  49         s32 success_ratio;
  50         s32 counter;
  51         s32 average_tpt;
  52         unsigned long stamp;
  53 };
  54
  55 struct iwl3945_rs_sta {
  56         spinlock_t lock;
  57         s32 *expected_tpt;
  58         unsigned long last_partial_flush;
  59         unsigned long last_flush;
  60         u32 flush_time;
  61         u32 last_tx_packets;
  62         u32 tx_packets;
  63         u8 tgg;
  64         u8 flush_pending;
  65         u8 start_rate;
  66         u8 ibss_sta_added;
  67         struct timer_list rate_scale_flush;
  68         struct iwl3945_rate_scale_data win[IWL_RATE_COUNT];
  69 };
  70
  71 static s32 iwl3945_expected_tpt_g[IWL_RATE_COUNT] = {
  72         7, 13, 35, 58, 0, 0, 76, 104, 130, 168, 191, 202
  73 };
  74
  75 static s32 iwl3945_expected_tpt_g_prot[IWL_RATE_COUNT] = {
  76         7, 13, 35, 58, 0, 0, 0, 80, 93, 113, 123, 125
  77 };
  78
  79 static s32 iwl3945_expected_tpt_a[IWL_RATE_COUNT] = {
  80         0, 0, 0, 0, 40, 57, 72, 98, 121, 154, 177, 186
  81 };
  82
  83 static s32 iwl3945_expected_tpt_b[IWL_RATE_COUNT] = {
  84         7, 13, 35, 58, 0, 0, 0, 0, 0, 0, 0, 0
  85 };
  86
  87 struct iwl3945_tpt_entry {
  88         s8 min_rssi;
  89         u8 index;
  90 };
  91
  92 static struct iwl3945_tpt_entry iwl3945_tpt_table_a[] = {
  93         {-60, IWL_RATE_54M_INDEX},
  94         {-64, IWL_RATE_48M_INDEX},
  95         {-72, IWL_RATE_36M_INDEX},
  96         {-80, IWL_RATE_24M_INDEX},
  97         {-84, IWL_RATE_18M_INDEX},
  98         {-85, IWL_RATE_12M_INDEX},
  99         {-87, IWL_RATE_9M_INDEX},
 100         {-89, IWL_RATE_6M_INDEX}
 101 };
 102
 103 static struct iwl3945_tpt_entry iwl3945_tpt_table_b[] = {
 104         {-86, IWL_RATE_11M_INDEX},
 105         {-88, IWL_RATE_5M_INDEX},
 106         {-90, IWL_RATE_2M_INDEX},
 107         {-92, IWL_RATE_1M_INDEX}
 108
 109 };
 110
 111 static struct iwl3945_tpt_entry iwl3945_tpt_table_g[] = {
 112         {-60, IWL_RATE_54M_INDEX},
 113         {-64, IWL_RATE_48M_INDEX},
 114         {-68, IWL_RATE_36M_INDEX},
 115         {-80, IWL_RATE_24M_INDEX},
 116         {-84, IWL_RATE_18M_INDEX},
 117         {-85, IWL_RATE_12M_INDEX},
 118         {-86, IWL_RATE_11M_INDEX},
 119         {-88, IWL_RATE_5M_INDEX},
 120         {-90, IWL_RATE_2M_INDEX},
 121         {-92, IWL_RATE_1M_INDEX}
 122 };
 123
 124 #define IWL_RATE_MAX_WINDOW          62
 125 #define IWL_RATE_FLUSH        (3*HZ/10)
 126 #define IWL_RATE_WIN_FLUSH       (HZ/2)
 127 #define IWL_RATE_HIGH_TH          11520
 128 #define IWL_RATE_MIN_FAILURE_TH       8
 129 #define IWL_RATE_MIN_SUCCESS_TH       8
 130 #define IWL_RATE_DECREASE_TH       1920
 131
 132 static u8 iwl3945_get_rate_index_by_rssi(s32 rssi, u8 mode)
 133 {
 134         u32 index = 0;
 135         u32 table_size = 0;
 136         struct iwl3945_tpt_entry *tpt_table = NULL;
 137
 138         if ((rssi < IWL_MIN_RSSI_VAL) || (rssi > IWL_MAX_RSSI_VAL))
 139                 rssi = IWL_MIN_RSSI_VAL;
 140
 141         switch (mode) {
 142         case MODE_IEEE80211G:
 143                 tpt_table = iwl3945_tpt_table_g;
 144                 table_size = ARRAY_SIZE(iwl3945_tpt_table_g);
 145                 break;
 146
 147         case MODE_IEEE80211A:
 148                 tpt_table = iwl3945_tpt_table_a;
 149                 table_size = ARRAY_SIZE(iwl3945_tpt_table_a);
 150                 break;
 151
 152         default:
 153         case MODE_IEEE80211B:
 154                 tpt_table = iwl3945_tpt_table_b;
 155                 table_size = ARRAY_SIZE(iwl3945_tpt_table_b);
 156                 break;
 157         }
 158
 159         while ((index < table_size) && (rssi < tpt_table[index].min_rssi))
 160                 index++;
 161
 162         index = min(index, (table_size - 1));
 163
 164         return tpt_table[index].index;
 165 }
 166
 167 static void iwl3945_clear_window(struct iwl3945_rate_scale_data *window)
 168 {
 169         window->data = 0;
 170         window->success_counter = 0;
 171         window->success_ratio = IWL_INVALID_VALUE;
 172         window->counter = 0;
 173         window->average_tpt = IWL_INVALID_VALUE;
 174         window->stamp = 0;
 175 }
 176
 177 /**
 178  * iwl3945_rate_scale_flush_windows - flush out the rate scale windows
 179  *
 180  * Returns the number of windows that have gathered data but were
 181  * not flushed.  If there were any that were not flushed, then
 182  * reschedule the rate flushing routine.
 183  */
 184 static int iwl3945_rate_scale_flush_windows(struct iwl3945_rs_sta *rs_sta)
 185 {
 186         int unflushed = 0;
 187         int i;
 188         unsigned long flags;
 189
 190         /*
 191          * For each rate, if we have collected data on that rate
 192          * and it has been more than IWL_RATE_WIN_FLUSH
 193          * since we flushed, clear out the gathered statistics
 194          */
 195         for (i = 0; i < IWL_RATE_COUNT; i++) {
 196                 if (!rs_sta->win[i].counter)
 197                         continue;
 198
 199                 spin_lock_irqsave(&rs_sta->lock, flags);
 200                 if (time_after(jiffies, rs_sta->win[i].stamp +
 201                                IWL_RATE_WIN_FLUSH)) {
 202                         IWL_DEBUG_RATE("flushing %d samples of rate "
 203                                        "index %d\n",
 204                                        rs_sta->win[i].counter, i);
 205                         iwl3945_clear_window(&rs_sta->win[i]);
 206                 } else
 207                         unflushed++;
 208                 spin_unlock_irqrestore(&rs_sta->lock, flags);
 209         }
 210
 211         return unflushed;
 212 }
 213
 214 #define IWL_RATE_FLUSH_MAX              5000    /* msec */
 215 #define IWL_RATE_FLUSH_MIN              50      /* msec */
 216
 217 static void iwl3945_bg_rate_scale_flush(unsigned long data)
 218 {
 219         struct iwl3945_rs_sta *rs_sta = (void *)data;
 220         int unflushed = 0;
 221         unsigned long flags;
 222         u32 packet_count, duration, pps;
 223
 224         IWL_DEBUG_RATE("enter\n");
 225
 226         unflushed = iwl3945_rate_scale_flush_windows(rs_sta);
 227
 228         spin_lock_irqsave(&rs_sta->lock, flags);
 229
 230         rs_sta->flush_pending = 0;
 231
 232         /* Number of packets Rx'd since last time this timer ran */
 233         packet_count = (rs_sta->tx_packets - rs_sta->last_tx_packets) + 1;
 234
 235         rs_sta->last_tx_packets = rs_sta->tx_packets + 1;
 236
 237         if (unflushed) {
 238                 duration =
 239                     jiffies_to_msecs(jiffies - rs_sta->last_partial_flush);
 240 /*              duration = jiffies_to_msecs(rs_sta->flush_time); */
 241
 242                 IWL_DEBUG_RATE("Tx'd %d packets in %dms\n",
 243                                packet_count, duration);
 244
 245                 /* Determine packets per second */
 246                 if (duration)
 247                         pps = (packet_count * 1000) / duration;
 248                 else
 249                         pps = 0;
 250
 251                 if (pps) {
 252                         duration = IWL_RATE_FLUSH_MAX / pps;
 253                         if (duration < IWL_RATE_FLUSH_MIN)
 254                                 duration = IWL_RATE_FLUSH_MIN;
 255                 } else
 256                         duration = IWL_RATE_FLUSH_MAX;
 257
 258                 rs_sta->flush_time = msecs_to_jiffies(duration);
 259
 260                 IWL_DEBUG_RATE("new flush period: %d msec ave %d\n",
 261                                duration, packet_count);
 262
 263                 mod_timer(&rs_sta->rate_scale_flush, jiffies +
 264                           rs_sta->flush_time);
 265
 266                 rs_sta->last_partial_flush = jiffies;
 267         }
 268
 269         /* If there weren't any unflushed entries, we don't schedule the timer
 270          * to run again */
 271
 272         rs_sta->last_flush = jiffies;
 273
 274         spin_unlock_irqrestore(&rs_sta->lock, flags);
 275
 276         IWL_DEBUG_RATE("leave\n");
 277 }
 278
 279 /**
 280  * iwl3945_collect_tx_data - Update the success/failure sliding window
 281  *
 282  * We keep a sliding window of the last 64 packets transmitted
 283  * at this rate.  window->data contains the bitmask of successful
 284  * packets.
 285  */
 286 static void iwl3945_collect_tx_data(struct iwl3945_rs_sta *rs_sta,
 287                                 struct iwl3945_rate_scale_data *window,
 288                                 int success, int retries)
 289 {
 290         unsigned long flags;
 291
 292         if (!retries) {
 293                 IWL_DEBUG_RATE("leave: retries == 0 -- should be at least 1\n");
 294                 return;
 295         }
 296
 297         while (retries--) {
 298                 spin_lock_irqsave(&rs_sta->lock, flags);
 299
 300                 /* If we have filled up the window then subtract one from the
 301                  * success counter if the high-bit is counting toward
 302                  * success */
 303                 if (window->counter == IWL_RATE_MAX_WINDOW) {
 304                         if (window->data & (1ULL << (IWL_RATE_MAX_WINDOW - 1)))
 305                                 window->success_counter--;
 306                 } else
 307                         window->counter++;
 308
 309                 /* Slide the window to the left one bit */
 310                 window->data = (window->data << 1);
 311
 312                 /* If this packet was a success then set the low bit high */
 313                 if (success) {
 314                         window->success_counter++;
 315                         window->data |= 1;
 316                 }
 317
 318                 /* window->counter can't be 0 -- it is either >0 or
 319                  * IWL_RATE_MAX_WINDOW */
 320                 window->success_ratio = 12800 * window->success_counter /
 321                     window->counter;
 322
 323                 /* Tag this window as having been updated */
 324                 window->stamp = jiffies;
 325
 326                 spin_unlock_irqrestore(&rs_sta->lock, flags);
 327         }
 328 }
 329
 330 static void rs_rate_init(void *priv_rate, void *priv_sta,
 331                          struct ieee80211_local *local, struct sta_info *sta)
 332 {
 333         int i;
 334
 335         IWL_DEBUG_RATE("enter\n");
 336
 337         /* TODO: what is a good starting rate for STA? About middle? Maybe not
 338          * the lowest or the highest rate.. Could consider using RSSI from
 339          * previous packets? Need to have IEEE 802.1X auth succeed immediately
 340          * after assoc.. */
 341
 342         for (i = IWL_RATE_COUNT - 1; i >= 0; i--) {
 343                 if (sta->supp_rates & (1 << i)) {
 344                         sta->txrate = i;
 345                         break;
 346                 }
 347         }
 348
 349         sta->last_txrate = sta->txrate;
 350
 351         /* For MODE_IEEE80211A mode it start at IWL_FIRST_OFDM_RATE */
 352         if (local->hw.conf.phymode == MODE_IEEE80211A)
 353                 sta->last_txrate += IWL_FIRST_OFDM_RATE;
 354
 355         IWL_DEBUG_RATE("leave\n");
 356 }
 357
 358 static void *rs_alloc(struct ieee80211_local *local)
 359 {
 360         return local->hw.priv;
 361 }
 362
 363 /* rate scale requires free function to be implemented */
 364 static void rs_free(void *priv)
 365 {
 366         return;
 367 }
 368 static void rs_clear(void *priv)
 369 {
 370         return;
 371 }
 372
 373
 374 static void *rs_alloc_sta(void *priv, gfp_t gfp)
 375 {
 376         struct iwl3945_rs_sta *rs_sta;
 377         int i;
 378
 379         IWL_DEBUG_RATE("enter\n");
 380
 381         rs_sta = kzalloc(sizeof(struct iwl3945_rs_sta), gfp);
 382         if (!rs_sta) {
 383                 IWL_DEBUG_RATE("leave: ENOMEM\n");
 384                 return NULL;
 385         }
 386
 387         spin_lock_init(&rs_sta->lock);
 388
 389         rs_sta->start_rate = IWL_RATE_INVALID;
 390
 391         /* default to just 802.11b */
 392         rs_sta->expected_tpt = iwl3945_expected_tpt_b;
 393
 394         rs_sta->last_partial_flush = jiffies;
 395         rs_sta->last_flush = jiffies;
 396         rs_sta->flush_time = IWL_RATE_FLUSH;
 397         rs_sta->last_tx_packets = 0;
 398         rs_sta->ibss_sta_added = 0;
 399
 400         init_timer(&rs_sta->rate_scale_flush);
 401         rs_sta->rate_scale_flush.data = (unsigned long)rs_sta;
 402         rs_sta->rate_scale_flush.function = &iwl3945_bg_rate_scale_flush;
 403
 404         for (i = 0; i < IWL_RATE_COUNT; i++)
 405                 iwl3945_clear_window(&rs_sta->win[i]);
 406
 407         IWL_DEBUG_RATE("leave\n");
 408
 409         return rs_sta;
 410 }
 411
 412 static void rs_free_sta(void *priv, void *priv_sta)
 413 {
 414         struct iwl3945_rs_sta *rs_sta = priv_sta;
 415
 416         IWL_DEBUG_RATE("enter\n");
 417         del_timer_sync(&rs_sta->rate_scale_flush);
 418         kfree(rs_sta);
 419         IWL_DEBUG_RATE("leave\n");
 420 }
 421
 422
 423 /*
 424  * get ieee prev rate from rate scale table.
 425  * for A and B mode we need to overright prev
 426  * value
 427  */
 428 static int rs_adjust_next_rate(struct iwl3945_priv *priv, int rate)
 429 {
 430         int next_rate = iwl3945_get_prev_ieee_rate(rate);
 431
 432         switch (priv->phymode) {
 433         case MODE_IEEE80211A:
 434                 if (rate == IWL_RATE_12M_INDEX)
 435                         next_rate = IWL_RATE_9M_INDEX;
 436                 else if (rate == IWL_RATE_6M_INDEX)
 437                         next_rate = IWL_RATE_6M_INDEX;
 438                 break;
 439         case MODE_IEEE80211B:
 440                 if (rate == IWL_RATE_11M_INDEX_TABLE)
 441                         next_rate = IWL_RATE_5M_INDEX_TABLE;
 442                 break;
 443         default:
 444                 break;
 445         }
 446
 447         return next_rate;
 448 }
 449 /**
 450  * rs_tx_status - Update rate control values based on Tx results
 451  *
 452  * NOTE: Uses iwl3945_priv->retry_rate for the # of retries attempted by
 453  * the hardware for each rate.
 454  */
 455 static void rs_tx_status(void *priv_rate,
 456                          struct net_device *dev,
 457                          struct sk_buff *skb,
 458                          struct ieee80211_tx_status *tx_resp)
 459 {
 460         u8 retries, current_count;
 461         int scale_rate_index, first_index, last_index;
 462         unsigned long flags;
 463         struct sta_info *sta;
 464         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 465         struct iwl3945_priv *priv = (struct iwl3945_priv *)priv_rate;
 466         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
 467         struct iwl3945_rs_sta *rs_sta;
 468
 469         IWL_DEBUG_RATE("enter\n");
 470
 471         retries = tx_resp->retry_count;
 472
 473         first_index = tx_resp->control.tx_rate;
 474         if ((first_index < 0) || (first_index >= IWL_RATE_COUNT)) {
 475                 IWL_DEBUG_RATE("leave: Rate out of bounds: %0x for %d\n",
 476                                tx_resp->control.tx_rate, first_index);
 477                 return;
 478         }
 479
 480         sta = sta_info_get(local, hdr->addr1);
 481         if (!sta || !sta->rate_ctrl_priv) {
 482                 if (sta)
 483                         sta_info_put(sta);
 484                 IWL_DEBUG_RATE("leave: No STA priv data to update!\n");
 485                 return;
 486         }
 487
 488         rs_sta = (void *)sta->rate_ctrl_priv;
 489
 490         rs_sta->tx_packets++;
 491
 492         scale_rate_index = first_index;
 493         last_index = first_index;
 494
 495         /*
 496          * Update the window for each rate.  We determine which rates
 497          * were Tx'd based on the total number of retries vs. the number
 498          * of retries configured for each rate -- currently set to the
 499          * priv value 'retry_rate' vs. rate specific
 500          *
 501          * On exit from this while loop last_index indicates the rate
 502          * at which the frame was finally transmitted (or failed if no
 503          * ACK)
 504          */
 505         while (retries > 0) {
 506                 if (retries < priv->retry_rate) {
 507                         current_count = retries;
 508                         last_index = scale_rate_index;
 509                 } else {
 510                         current_count = priv->retry_rate;
 511                         last_index = rs_adjust_next_rate(priv,
 512                                                          scale_rate_index);
 513                 }
 514
 515                 /* Update this rate accounting for as many retries
 516                  * as was used for it (per current_count) */
 517                 iwl3945_collect_tx_data(rs_sta,
 518                                     &rs_sta->win[scale_rate_index],
 519                                     0, current_count);
 520                 IWL_DEBUG_RATE("Update rate %d for %d retries.\n",
 521                                scale_rate_index, current_count);
 522
 523                 retries -= current_count;
 524
 525                 if (retries)
 526                         scale_rate_index =
 527                             rs_adjust_next_rate(priv, scale_rate_index);
 528         }
 529
 530
 531         /* Update the last index window with success/failure based on ACK */
 532         IWL_DEBUG_RATE("Update rate %d with %s.\n",
 533                        last_index,
 534                        (tx_resp->flags & IEEE80211_TX_STATUS_ACK) ?
 535                        "success" : "failure");
 536         iwl3945_collect_tx_data(rs_sta,
 537                             &rs_sta->win[last_index],
 538                             tx_resp->flags & IEEE80211_TX_STATUS_ACK, 1);
 539
 540         /* We updated the rate scale window -- if its been more than
 541          * flush_time since the last run, schedule the flush
 542          * again */
 543         spin_lock_irqsave(&rs_sta->lock, flags);
 544
 545         if (!rs_sta->flush_pending &&
 546             time_after(jiffies, rs_sta->last_partial_flush +
 547                        rs_sta->flush_time)) {
 548
 549                 rs_sta->flush_pending = 1;
 550                 mod_timer(&rs_sta->rate_scale_flush,
 551                           jiffies + rs_sta->flush_time);
 552         }
 553
 554         spin_unlock_irqrestore(&rs_sta->lock, flags);
 555
 556         sta_info_put(sta);
 557
 558         IWL_DEBUG_RATE("leave\n");
 559
 560         return;
 561 }
 562
 563 static u16 iwl3945_get_adjacent_rate(struct iwl3945_rs_sta *rs_sta,
 564                                  u8 index, u16 rate_mask, int phymode)
 565 {
 566         u8 high = IWL_RATE_INVALID;
 567         u8 low = IWL_RATE_INVALID;
 568
 569         /* 802.11A walks to the next literal adjacent rate in
 570          * the rate table */
 571         if (unlikely(phymode == MODE_IEEE80211A)) {
 572                 int i;
 573                 u32 mask;
 574
 575                 /* Find the previous rate that is in the rate mask */
 576                 i = index - 1;
 577                 for (mask = (1 << i); i >= 0; i--, mask >>= 1) {
 578                         if (rate_mask & mask) {
 579                                 low = i;
 580                                 break;
 581                         }
 582                 }
 583
 584                 /* Find the next rate that is in the rate mask */
 585                 i = index + 1;
 586                 for (mask = (1 << i); i < IWL_RATE_COUNT; i++, mask <<= 1) {
 587                         if (rate_mask & mask) {
 588                                 high = i;
 589                                 break;
 590                         }
 591                 }
 592
 593                 return (high << 8) | low;
 594         }
 595
 596         low = index;
 597         while (low != IWL_RATE_INVALID) {
 598                 if (rs_sta->tgg)
 599                         low = iwl3945_rates[low].prev_rs_tgg;
 600                 else
 601                         low = iwl3945_rates[low].prev_rs;
 602                 if (low == IWL_RATE_INVALID)
 603                         break;
 604                 if (rate_mask & (1 << low))
 605                         break;
 606                 IWL_DEBUG_RATE("Skipping masked lower rate: %d\n", low);
 607         }
 608
 609         high = index;
 610         while (high != IWL_RATE_INVALID) {
 611                 if (rs_sta->tgg)
 612                         high = iwl3945_rates[high].next_rs_tgg;
 613                 else
 614                         high = iwl3945_rates[high].next_rs;
 615                 if (high == IWL_RATE_INVALID)
 616                         break;
 617                 if (rate_mask & (1 << high))
 618                         break;
 619                 IWL_DEBUG_RATE("Skipping masked higher rate: %d\n", high);
 620         }
 621
 622         return (high << 8) | low;
 623 }
 624
 625 /**
 626  * rs_get_rate - find the rate for the requested packet
 627  *
 628  * Returns the ieee80211_rate structure allocated by the driver.
 629  *
 630  * The rate control algorithm has no internal mapping between hw_mode's
 631  * rate ordering and the rate ordering used by the rate control algorithm.
 632  *
 633  * The rate control algorithm uses a single table of rates that goes across
 634  * the entire A/B/G spectrum vs. being limited to just one particular
 635  * hw_mode.
 636  *
 637  * As such, we can't convert the index obtained below into the hw_mode's
 638  * rate table and must reference the driver allocated rate table
 639  *
 640  */
 641 static void rs_get_rate(void *priv_rate, struct net_device *dev,
 642                         struct ieee80211_hw_mode *mode, struct sk_buff *skb,
 643                         struct rate_selection *sel)
 644 {
 645         u8 low = IWL_RATE_INVALID;
 646         u8 high = IWL_RATE_INVALID;
 647         u16 high_low;
 648         int index;
 649         struct iwl3945_rs_sta *rs_sta;
 650         struct iwl3945_rate_scale_data *window = NULL;
 651         int current_tpt = IWL_INVALID_VALUE;
 652         int low_tpt = IWL_INVALID_VALUE;
 653         int high_tpt = IWL_INVALID_VALUE;
 654         u32 fail_count;
 655         s8 scale_action = 0;
 656         unsigned long flags;
 657         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
 658         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 659         struct sta_info *sta;
 660         u16 fc, rate_mask;
 661         struct iwl3945_priv *priv = (struct iwl3945_priv *)priv_rate;
 662         DECLARE_MAC_BUF(mac);
 663
 664         IWL_DEBUG_RATE("enter\n");
 665
 666         sta = sta_info_get(local, hdr->addr1);
 667
 668         /* Send management frames and broadcast/multicast data using lowest
 669          * rate. */
 670         fc = le16_to_cpu(hdr->frame_control);
 671         if ((fc & IEEE80211_FCTL_FTYPE) != IEEE80211_FTYPE_DATA ||
 672             is_multicast_ether_addr(hdr->addr1) ||
 673             !sta || !sta->rate_ctrl_priv) {
 674                 IWL_DEBUG_RATE("leave: No STA priv data to update!\n");
 675                 sel->rate = rate_lowest(local, local->oper_hw_mode, sta);
 676                 if (sta)
 677                         sta_info_put(sta);
 678                 return;
 679         }
 680
 681         rate_mask = sta->supp_rates;
 682         index = min(sta->last_txrate & 0xffff, IWL_RATE_COUNT - 1);
 683
 684         if (priv->phymode == (u8) MODE_IEEE80211A)
 685                 rate_mask = rate_mask << IWL_FIRST_OFDM_RATE;
 686
 687         rs_sta = (void *)sta->rate_ctrl_priv;
 688
 689         if ((priv->iw_mode == IEEE80211_IF_TYPE_IBSS) &&
 690             !rs_sta->ibss_sta_added) {
 691                 u8 sta_id = iwl3945_hw_find_station(priv, hdr->addr1);
 692
 693                 if (sta_id == IWL_INVALID_STATION) {
 694                         IWL_DEBUG_RATE("LQ: ADD station %s\n",
 695                                        print_mac(mac, hdr->addr1));
 696                         sta_id = iwl3945_add_station(priv,
 697                                     hdr->addr1, 0, CMD_ASYNC);
 698                 }
 699                 if (sta_id != IWL_INVALID_STATION)
 700                         rs_sta->ibss_sta_added = 1;
 701         }
 702
 703         spin_lock_irqsave(&rs_sta->lock, flags);
 704
 705         if (rs_sta->start_rate != IWL_RATE_INVALID) {
 706                 index = rs_sta->start_rate;
 707                 rs_sta->start_rate = IWL_RATE_INVALID;
 708         }
 709
 710         window = &(rs_sta->win[index]);
 711
 712         fail_count = window->counter - window->success_counter;
 713
 714         if (((fail_count <= IWL_RATE_MIN_FAILURE_TH) &&
 715              (window->success_counter < IWL_RATE_MIN_SUCCESS_TH))) {
 716                 window->average_tpt = IWL_INVALID_VALUE;
 717                 spin_unlock_irqrestore(&rs_sta->lock, flags);
 718
 719                 IWL_DEBUG_RATE("Invalid average_tpt on rate %d: "
 720                                "counter: %d, success_counter: %d, "
 721                                "expected_tpt is %sNULL\n",
 722                                index,
 723                                window->counter,
 724                                window->success_counter,
 725                                rs_sta->expected_tpt ? "not " : "");
 726                 goto out;
 727
 728         }
 729
 730         window->average_tpt = ((window->success_ratio *
 731                                 rs_sta->expected_tpt[index] + 64) / 128);
 732         current_tpt = window->average_tpt;
 733
 734         high_low = iwl3945_get_adjacent_rate(rs_sta, index, rate_mask,
 735                                          local->hw.conf.phymode);
 736         low = high_low & 0xff;
 737         high = (high_low >> 8) & 0xff;
 738
 739         if (low != IWL_RATE_INVALID)
 740                 low_tpt = rs_sta->win[low].average_tpt;
 741
 742         if (high != IWL_RATE_INVALID)
 743                 high_tpt = rs_sta->win[high].average_tpt;
 744
 745         spin_unlock_irqrestore(&rs_sta->lock, flags);
 746
 747         scale_action = 1;
 748
 749         if ((window->success_ratio < IWL_RATE_DECREASE_TH) || !current_tpt) {
 750                 IWL_DEBUG_RATE("decrease rate because of low success_ratio\n");
 751                 scale_action = -1;
 752         } else if ((low_tpt == IWL_INVALID_VALUE) &&
 753                    (high_tpt == IWL_INVALID_VALUE))
 754                 scale_action = 1;
 755         else if ((low_tpt != IWL_INVALID_VALUE) &&
 756                    (high_tpt != IWL_INVALID_VALUE)
 757                    && (low_tpt < current_tpt)
 758                    && (high_tpt < current_tpt)) {
 759                 IWL_DEBUG_RATE("No action -- low [%d] & high [%d] < "
 760                                "current_tpt [%d]\n",
 761                                low_tpt, high_tpt, current_tpt);
 762                 scale_action = 0;
 763         } else {
 764                 if (high_tpt != IWL_INVALID_VALUE) {
 765                         if (high_tpt > current_tpt)
 766                                 scale_action = 1;
 767                         else {
 768                                 IWL_DEBUG_RATE
 769                                     ("decrease rate because of high tpt\n");
 770                                 scale_action = -1;
 771                         }
 772                 } else if (low_tpt != IWL_INVALID_VALUE) {
 773                         if (low_tpt > current_tpt) {
 774                                 IWL_DEBUG_RATE
 775                                     ("decrease rate because of low tpt\n");
 776                                 scale_action = -1;
 777                         } else
 778                                 scale_action = 1;
 779                 }
 780         }
 781
 782         if ((window->success_ratio > IWL_RATE_HIGH_TH) ||
 783             (current_tpt > window->average_tpt)) {
 784                 IWL_DEBUG_RATE("No action -- success_ratio [%d] > HIGH_TH or "
 785                                "current_tpt [%d] > average_tpt [%d]\n",
 786                                window->success_ratio,
 787                                current_tpt, window->average_tpt);
 788                 scale_action = 0;
 789         }
 790
 791         switch (scale_action) {
 792         case -1:
 793                 if (low != IWL_RATE_INVALID)
 794                         index = low;
 795                 break;
 796
 797         case 1:
 798                 if (high != IWL_RATE_INVALID)
 799                         index = high;
 800
 801                 break;
 802
 803         case 0:
 804         default:
 805                 break;
 806         }
 807
 808         IWL_DEBUG_RATE("Selected %d (action %d) - low %d high %d\n",
 809                        index, scale_action, low, high);
 810
 811  out:
 812
 813         sta->last_txrate = index;
 814         if (priv->phymode == (u8) MODE_IEEE80211A)
 815                 sta->txrate = sta->last_txrate - IWL_FIRST_OFDM_RATE;
 816         else
 817                 sta->txrate = sta->last_txrate;
 818
 819         sta_info_put(sta);
 820
 821         IWL_DEBUG_RATE("leave: %d\n", index);
 822
 823         sel->rate = &priv->ieee_rates[index];
 824 }
 825
 826 static struct rate_control_ops rs_ops = {
 827         .module = NULL,
 828         .name = RS_NAME,
 829         .tx_status = rs_tx_status,
 830         .get_rate = rs_get_rate,
 831         .rate_init = rs_rate_init,
 832         .clear = rs_clear,
 833         .alloc = rs_alloc,
 834         .free = rs_free,
 835         .alloc_sta = rs_alloc_sta,
 836         .free_sta = rs_free_sta,
 837 };
 838
 839 int iwl3945_fill_rs_info(struct ieee80211_hw *hw, char *buf, u8 sta_id)
 840 {
 841         struct ieee80211_local *local = hw_to_local(hw);
 842         struct iwl3945_priv *priv = hw->priv;
 843         struct iwl3945_rs_sta *rs_sta;
 844         struct sta_info *sta;
 845         unsigned long flags;
 846         int count = 0, i;
 847         u32 samples = 0, success = 0, good = 0;
 848         unsigned long now = jiffies;
 849         u32 max_time = 0;
 850
 851         sta = sta_info_get(local, priv->stations[sta_id].sta.sta.addr);
 852         if (!sta || !sta->rate_ctrl_priv) {
 853                 if (sta) {
 854                         sta_info_put(sta);
 855                         IWL_DEBUG_RATE("leave - no private rate data!\n");
 856                 } else
 857                         IWL_DEBUG_RATE("leave - no station!\n");
 858                 return sprintf(buf, "station %d not found\n", sta_id);
 859         }
 860
 861         rs_sta = (void *)sta->rate_ctrl_priv;
 862         spin_lock_irqsave(&rs_sta->lock, flags);
 863         i = IWL_RATE_54M_INDEX;
 864         while (1) {
 865                 u64 mask;
 866                 int j;
 867
 868                 count +=
 869                     sprintf(&buf[count], " %2dMbs: ", iwl3945_rates[i].ieee / 2);
 870
 871                 mask = (1ULL << (IWL_RATE_MAX_WINDOW - 1));
 872                 for (j = 0; j < IWL_RATE_MAX_WINDOW; j++, mask >>= 1)
 873                         buf[count++] =
 874                             (rs_sta->win[i].data & mask) ? '1' : '0';
 875
 876                 samples += rs_sta->win[i].counter;
 877                 good += rs_sta->win[i].success_counter;
 878                 success += rs_sta->win[i].success_counter *
 879                                                 iwl3945_rates[i].ieee;
 880
 881                 if (rs_sta->win[i].stamp) {
 882                         int delta =
 883                             jiffies_to_msecs(now - rs_sta->win[i].stamp);
 884
 885                         if (delta > max_time)
 886                                 max_time = delta;
 887
 888                         count += sprintf(&buf[count], "%5dms\n", delta);
 889                 } else
 890                         buf[count++] = '\n';
 891
 892                 j = iwl3945_get_prev_ieee_rate(i);
 893                 if (j == i)
 894                         break;
 895                 i = j;
 896         }
 897         spin_unlock_irqrestore(&rs_sta->lock, flags);
 898         sta_info_put(sta);
 899
 900         /* Display the average rate of all samples taken.
 901          *
 902          * NOTE:  We multiple # of samples by 2 since the IEEE measurement
 903          * added from iwl3945_rates is actually 2X the rate */
 904         if (samples)
 905                 count += sprintf(
 906                         &buf[count],
 907                         "\nAverage rate is %3d.%02dMbs over last %4dms\n"
 908                         "%3d%% success (%d good packets over %d tries)\n",
 909                         success / (2 * samples), (success * 5 / samples) % 10,
 910                         max_time, good * 100 / samples, good, samples);
 911         else
 912                 count += sprintf(&buf[count], "\nAverage rate: 0Mbs\n");
 913
 914         return count;
 915 }
 916
 917 void iwl3945_rate_scale_init(struct ieee80211_hw *hw, s32 sta_id)
 918 {
 919         struct iwl3945_priv *priv = hw->priv;
 920         s32 rssi = 0;
 921         unsigned long flags;
 922         struct ieee80211_local *local = hw_to_local(hw);
 923         struct iwl3945_rs_sta *rs_sta;
 924         struct sta_info *sta;
 925
 926         IWL_DEBUG_RATE("enter\n");
 927
 928         if (!local->rate_ctrl->ops->name ||
 929             strcmp(local->rate_ctrl->ops->name, RS_NAME)) {
 930                 IWL_WARNING("iwl-3945-rs not selected as rate control algo!\n");
 931                 IWL_DEBUG_RATE("leave - mac80211 picked the wrong RC algo.\n");
 932                 return;
 933         }
 934
 935         sta = sta_info_get(local, priv->stations[sta_id].sta.sta.addr);
 936         if (!sta || !sta->rate_ctrl_priv) {
 937                 if (sta)
 938                         sta_info_put(sta);
 939                 IWL_DEBUG_RATE("leave - no private rate data!\n");
 940                 return;
 941         }
 942
 943         rs_sta = (void *)sta->rate_ctrl_priv;
 944
 945         spin_lock_irqsave(&rs_sta->lock, flags);
 946
 947         rs_sta->tgg = 0;
 948         switch (priv->phymode) {
 949         case MODE_IEEE80211G:
 950                 if (priv->active_rxon.flags & RXON_FLG_TGG_PROTECT_MSK) {
 951                         rs_sta->tgg = 1;
 952                         rs_sta->expected_tpt = iwl3945_expected_tpt_g_prot;
 953                 } else
 954                         rs_sta->expected_tpt = iwl3945_expected_tpt_g;
 955                 break;
 956
 957         case MODE_IEEE80211A:
 958                 rs_sta->expected_tpt = iwl3945_expected_tpt_a;
 959                 break;
 960
 961         default:
 962                 IWL_WARNING("Invalid phymode.  Defaulting to 802.11b\n");
 963         case MODE_IEEE80211B:
 964                 rs_sta->expected_tpt = iwl3945_expected_tpt_b;
 965                 break;
 966         }
 967
 968         sta_info_put(sta);
 969         spin_unlock_irqrestore(&rs_sta->lock, flags);
 970
 971         rssi = priv->last_rx_rssi;
 972         if (rssi == 0)
 973                 rssi = IWL_MIN_RSSI_VAL;
 974
 975         IWL_DEBUG(IWL_DL_INFO | IWL_DL_RATE, "Network RSSI: %d\n", rssi);
 976
 977         rs_sta->start_rate =
 978                         iwl3945_get_rate_index_by_rssi(rssi, priv->phymode);
 979
 980         IWL_DEBUG_RATE("leave: rssi %d assign rate index: "
 981                        "%d (plcp 0x%x)\n", rssi, rs_sta->start_rate,
 982                        iwl3945_rates[rs_sta->start_rate].plcp);
 983 }
 984
 985 void iwl3945_rate_control_register(struct ieee80211_hw *hw)
 986 {
 987         ieee80211_rate_control_register(&rs_ops);
 988 }
 989
 990 void iwl3945_rate_control_unregister(struct ieee80211_hw *hw)
 991 {
 992         ieee80211_rate_control_unregister(&rs_ops);
 993 }
 994
 995