drivers/net/wireless/ath/carl9170/tx.c

   1 /*
   2  * Atheros CARL9170 driver
   3  *
   4  * 802.11 xmit & status routines
   5  *
   6  * Copyright 2008, Johannes Berg <johannes@sipsolutions.net>
   7  * Copyright 2009, 2010, Christian Lamparter <chunkeey@googlemail.com>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; see the file COPYING.  If not, see
  21  * http://www.gnu.org/licenses/.
  22  *
  23  * This file incorporates work covered by the following copyright and
  24  * permission notice:
  25  *    Copyright (c) 2007-2008 Atheros Communications, Inc.
  26  *
  27  *    Permission to use, copy, modify, and/or distribute this software for any
  28  *    purpose with or without fee is hereby granted, provided that the above
  29  *    copyright notice and this permission notice appear in all copies.
  30  *
  31  *    THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  32  *    WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  33  *    MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  34  *    ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  35  *    WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  36  *    ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  37  *    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  38  */
  39
  40 #include <linux/init.h>
  41 #include <linux/slab.h>
  42 #include <linux/module.h>
  43 #include <linux/etherdevice.h>
  44 #include <net/mac80211.h>
  45 #include "carl9170.h"
  46 #include "hw.h"
  47 #include "cmd.h"
  48
  49 static inline unsigned int __carl9170_get_queue(struct ar9170 *ar,
  50                                                 unsigned int queue)
  51 {
  52         if (unlikely(modparam_noht)) {
  53                 return queue;
  54         } else {
  55                 /*
  56                  * This is just another workaround, until
  57                  * someone figures out how to get QoS and
  58                  * AMPDU to play nicely together.
  59                  */
  60
  61                 return 2;               /* AC_BE */
  62         }
  63 }
  64
  65 static inline unsigned int carl9170_get_queue(struct ar9170 *ar,
  66                                               struct sk_buff *skb)
  67 {
  68         return __carl9170_get_queue(ar, skb_get_queue_mapping(skb));
  69 }
  70
  71 static bool is_mem_full(struct ar9170 *ar)
  72 {
  73         return (DIV_ROUND_UP(IEEE80211_MAX_FRAME_LEN, ar->fw.mem_block_size) >
  74                 atomic_read(&ar->mem_free_blocks));
  75 }
  76
  77 static void carl9170_tx_accounting(struct ar9170 *ar, struct sk_buff *skb)
  78 {
  79         int queue, i;
  80         bool mem_full;
  81
  82         atomic_inc(&ar->tx_total_queued);
  83
  84         queue = skb_get_queue_mapping(skb);
  85         spin_lock_bh(&ar->tx_stats_lock);
  86
  87         /*
  88          * The driver has to accept the frame, regardless if the queue is
  89          * full to the brim, or not. We have to do the queuing internally,
  90          * since mac80211 assumes that a driver which can operate with
  91          * aggregated frames does not reject frames for this reason.
  92          */
  93         ar->tx_stats[queue].len++;
  94         ar->tx_stats[queue].count++;
  95
  96         mem_full = is_mem_full(ar);
  97         for (i = 0; i < ar->hw->queues; i++) {
  98                 if (mem_full || ar->tx_stats[i].len >= ar->tx_stats[i].limit) {
  99                         ieee80211_stop_queue(ar->hw, i);
 100                         ar->queue_stop_timeout[i] = jiffies;
 101                 }
 102         }
 103
 104         spin_unlock_bh(&ar->tx_stats_lock);
 105 }
 106
 107 /* needs rcu_read_lock */
 108 static struct ieee80211_sta *__carl9170_get_tx_sta(struct ar9170 *ar,
 109                                                    struct sk_buff *skb)
 110 {
 111         struct _carl9170_tx_superframe *super = (void *) skb->data;
 112         struct ieee80211_hdr *hdr = (void *) super->frame_data;
 113         struct ieee80211_vif *vif;
 114         unsigned int vif_id;
 115
 116         vif_id = (super->s.misc & CARL9170_TX_SUPER_MISC_VIF_ID) >>
 117                  CARL9170_TX_SUPER_MISC_VIF_ID_S;
 118
 119         if (WARN_ON_ONCE(vif_id >= AR9170_MAX_VIRTUAL_MAC))
 120                 return NULL;
 121
 122         vif = rcu_dereference(ar->vif_priv[vif_id].vif);
 123         if (unlikely(!vif))
 124                 return NULL;
 125
 126         /*
 127          * Normally we should use wrappers like ieee80211_get_DA to get
 128          * the correct peer ieee80211_sta.
 129          *
 130          * But there is a problem with indirect traffic (broadcasts, or
 131          * data which is designated for other stations) in station mode.
 132          * The frame will be directed to the AP for distribution and not
 133          * to the actual destination.
 134          */
 135
 136         return ieee80211_find_sta(vif, hdr->addr1);
 137 }
 138
 139 static void carl9170_tx_ps_unblock(struct ar9170 *ar, struct sk_buff *skb)
 140 {
 141         struct ieee80211_sta *sta;
 142         struct carl9170_sta_info *sta_info;
 143
 144         rcu_read_lock();
 145         sta = __carl9170_get_tx_sta(ar, skb);
 146         if (unlikely(!sta))
 147                 goto out_rcu;
 148
 149         sta_info = (struct carl9170_sta_info *) sta->drv_priv;
 150         if (atomic_dec_return(&sta_info->pending_frames) == 0)
 151                 ieee80211_sta_block_awake(ar->hw, sta, false);
 152
 153 out_rcu:
 154         rcu_read_unlock();
 155 }
 156
 157 static void carl9170_tx_accounting_free(struct ar9170 *ar, struct sk_buff *skb)
 158 {
 159         int queue;
 160
 161         queue = skb_get_queue_mapping(skb);
 162
 163         spin_lock_bh(&ar->tx_stats_lock);
 164
 165         ar->tx_stats[queue].len--;
 166
 167         if (!is_mem_full(ar)) {
 168                 unsigned int i;
 169                 for (i = 0; i < ar->hw->queues; i++) {
 170                         if (ar->tx_stats[i].len >= CARL9170_NUM_TX_LIMIT_SOFT)
 171                                 continue;
 172
 173                         if (ieee80211_queue_stopped(ar->hw, i)) {
 174                                 unsigned long tmp;
 175
 176                                 tmp = jiffies - ar->queue_stop_timeout[i];
 177                                 if (tmp > ar->max_queue_stop_timeout[i])
 178                                         ar->max_queue_stop_timeout[i] = tmp;
 179                         }
 180
 181                         ieee80211_wake_queue(ar->hw, i);
 182                 }
 183         }
 184
 185         spin_unlock_bh(&ar->tx_stats_lock);
 186
 187         if (atomic_dec_and_test(&ar->tx_total_queued))
 188                 complete(&ar->tx_flush);
 189 }
 190
 191 static int carl9170_alloc_dev_space(struct ar9170 *ar, struct sk_buff *skb)
 192 {
 193         struct _carl9170_tx_superframe *super = (void *) skb->data;
 194         unsigned int chunks;
 195         int cookie = -1;
 196
 197         atomic_inc(&ar->mem_allocs);
 198
 199         chunks = DIV_ROUND_UP(skb->len, ar->fw.mem_block_size);
 200         if (unlikely(atomic_sub_return(chunks, &ar->mem_free_blocks) < 0)) {
 201                 atomic_add(chunks, &ar->mem_free_blocks);
 202                 return -ENOSPC;
 203         }
 204
 205         spin_lock_bh(&ar->mem_lock);
 206         cookie = bitmap_find_free_region(ar->mem_bitmap, ar->fw.mem_blocks, 0);
 207         spin_unlock_bh(&ar->mem_lock);
 208
 209         if (unlikely(cookie < 0)) {
 210                 atomic_add(chunks, &ar->mem_free_blocks);
 211                 return -ENOSPC;
 212         }
 213
 214         super = (void *) skb->data;
 215
 216         /*
 217          * Cookie #0 serves two special purposes:
 218          *  1. The firmware might use it generate BlockACK frames
 219          *     in responds of an incoming BlockAckReqs.
 220          *
 221          *  2. Prevent double-free bugs.
 222          */
 223         super->s.cookie = (u8) cookie + 1;
 224         return 0;
 225 }
 226
 227 static void carl9170_release_dev_space(struct ar9170 *ar, struct sk_buff *skb)
 228 {
 229         struct _carl9170_tx_superframe *super = (void *) skb->data;
 230         int cookie;
 231
 232         /* make a local copy of the cookie */
 233         cookie = super->s.cookie;
 234         /* invalidate cookie */
 235         super->s.cookie = 0;
 236
 237         /*
 238          * Do a out-of-bounds check on the cookie:
 239          *
 240          *  * cookie "0" is reserved and won't be assigned to any
 241          *    out-going frame. Internally however, it is used to
 242          *    mark no longer/un-accounted frames and serves as a
 243          *    cheap way of preventing frames from being freed
 244          *    twice by _accident_. NB: There is a tiny race...
 245          *
 246          *  * obviously, cookie number is limited by the amount
 247          *    of available memory blocks, so the number can
 248          *    never execeed the mem_blocks count.
 249          */
 250         if (unlikely(WARN_ON_ONCE(cookie == 0) ||
 251             WARN_ON_ONCE(cookie > ar->fw.mem_blocks)))
 252                 return;
 253
 254         atomic_add(DIV_ROUND_UP(skb->len, ar->fw.mem_block_size),
 255                    &ar->mem_free_blocks);
 256
 257         spin_lock_bh(&ar->mem_lock);
 258         bitmap_release_region(ar->mem_bitmap, cookie - 1, 0);
 259         spin_unlock_bh(&ar->mem_lock);
 260 }
 261
 262 /* Called from any context */
 263 static void carl9170_tx_release(struct kref *ref)
 264 {
 265         struct ar9170 *ar;
 266         struct carl9170_tx_info *arinfo;
 267         struct ieee80211_tx_info *txinfo;
 268         struct sk_buff *skb;
 269
 270         arinfo = container_of(ref, struct carl9170_tx_info, ref);
 271         txinfo = container_of((void *) arinfo, struct ieee80211_tx_info,
 272                               rate_driver_data);
 273         skb = container_of((void *) txinfo, struct sk_buff, cb);
 274
 275         ar = arinfo->ar;
 276         if (WARN_ON_ONCE(!ar))
 277                 return;
 278
 279         BUILD_BUG_ON(
 280             offsetof(struct ieee80211_tx_info, status.ampdu_ack_len) != 23);
 281
 282         memset(&txinfo->status.ampdu_ack_len, 0,
 283                sizeof(struct ieee80211_tx_info) -
 284                offsetof(struct ieee80211_tx_info, status.ampdu_ack_len));
 285
 286         if (atomic_read(&ar->tx_total_queued))
 287                 ar->tx_schedule = true;
 288
 289         if (txinfo->flags & IEEE80211_TX_CTL_AMPDU) {
 290                 if (!atomic_read(&ar->tx_ampdu_upload))
 291                         ar->tx_ampdu_schedule = true;
 292
 293                 if (txinfo->flags & IEEE80211_TX_STAT_AMPDU) {
 294                         struct _carl9170_tx_superframe *super;
 295
 296                         super = (void *)skb->data;
 297                         txinfo->status.ampdu_len = super->s.rix;
 298                         txinfo->status.ampdu_ack_len = super->s.cnt;
 299                 } else if (txinfo->flags & IEEE80211_TX_STAT_ACK) {
 300                         /*
 301                          * drop redundant tx_status reports:
 302                          *
 303                          * 1. ampdu_ack_len of the final tx_status does
 304                          *    include the feedback of this particular frame.
 305                          *
 306                          * 2. tx_status_irqsafe only queues up to 128
 307                          *    tx feedback reports and discards the rest.
 308                          *
 309                          * 3. minstrel_ht is picky, it only accepts
 310                          *    reports of frames with the TX_STATUS_AMPDU flag.
 311                          */
 312
 313                         dev_kfree_skb_any(skb);
 314                         return;
 315                 } else {
 316                         /*
 317                          * Frame has failed, but we want to keep it in
 318                          * case it was lost due to a power-state
 319                          * transition.
 320                          */
 321                 }
 322         }
 323
 324         skb_pull(skb, sizeof(struct _carl9170_tx_superframe));
 325         ieee80211_tx_status_irqsafe(ar->hw, skb);
 326 }
 327
 328 void carl9170_tx_get_skb(struct sk_buff *skb)
 329 {
 330         struct carl9170_tx_info *arinfo = (void *)
 331                 (IEEE80211_SKB_CB(skb))->rate_driver_data;
 332         kref_get(&arinfo->ref);
 333 }
 334
 335 int carl9170_tx_put_skb(struct sk_buff *skb)
 336 {
 337         struct carl9170_tx_info *arinfo = (void *)
 338                 (IEEE80211_SKB_CB(skb))->rate_driver_data;
 339
 340         return kref_put(&arinfo->ref, carl9170_tx_release);
 341 }
 342
 343 /* Caller must hold the tid_info->lock & rcu_read_lock */
 344 static void carl9170_tx_shift_bm(struct ar9170 *ar,
 345         struct carl9170_sta_tid *tid_info, u16 seq)
 346 {
 347         u16 off;
 348
 349         off = SEQ_DIFF(seq, tid_info->bsn);
 350
 351         if (WARN_ON_ONCE(off >= CARL9170_BAW_BITS))
 352                 return;
 353
 354         /*
 355          * Sanity check. For each MPDU we set the bit in bitmap and
 356          * clear it once we received the tx_status.
 357          * But if the bit is already cleared then we've been bitten
 358          * by a bug.
 359          */
 360         WARN_ON_ONCE(!test_and_clear_bit(off, tid_info->bitmap));
 361
 362         off = SEQ_DIFF(tid_info->snx, tid_info->bsn);
 363         if (WARN_ON_ONCE(off >= CARL9170_BAW_BITS))
 364                 return;
 365
 366         if (!bitmap_empty(tid_info->bitmap, off))
 367                 off = find_first_bit(tid_info->bitmap, off);
 368
 369         tid_info->bsn += off;
 370         tid_info->bsn &= 0x0fff;
 371
 372         bitmap_shift_right(tid_info->bitmap, tid_info->bitmap,
 373                            off, CARL9170_BAW_BITS);
 374 }
 375
 376 static void carl9170_tx_status_process_ampdu(struct ar9170 *ar,
 377         struct sk_buff *skb, struct ieee80211_tx_info *txinfo)
 378 {
 379         struct _carl9170_tx_superframe *super = (void *) skb->data;
 380         struct ieee80211_hdr *hdr = (void *) super->frame_data;
 381         struct ieee80211_sta *sta;
 382         struct carl9170_sta_info *sta_info;
 383         struct carl9170_sta_tid *tid_info;
 384         u8 tid;
 385
 386         if (!(txinfo->flags & IEEE80211_TX_CTL_AMPDU) ||
 387             txinfo->flags & IEEE80211_TX_CTL_INJECTED ||
 388            (!(super->f.mac_control & cpu_to_le16(AR9170_TX_MAC_AGGR))))
 389                 return;
 390
 391         rcu_read_lock();
 392         sta = __carl9170_get_tx_sta(ar, skb);
 393         if (unlikely(!sta))
 394                 goto out_rcu;
 395
 396         tid = get_tid_h(hdr);
 397
 398         sta_info = (void *) sta->drv_priv;
 399         tid_info = rcu_dereference(sta_info->agg[tid]);
 400         if (!tid_info)
 401                 goto out_rcu;
 402
 403         spin_lock_bh(&tid_info->lock);
 404         if (likely(tid_info->state >= CARL9170_TID_STATE_IDLE))
 405                 carl9170_tx_shift_bm(ar, tid_info, get_seq_h(hdr));
 406
 407         if (sta_info->stats[tid].clear) {
 408                 sta_info->stats[tid].clear = false;
 409                 sta_info->stats[tid].req = false;
 410                 sta_info->stats[tid].ampdu_len = 0;
 411                 sta_info->stats[tid].ampdu_ack_len = 0;
 412         }
 413
 414         sta_info->stats[tid].ampdu_len++;
 415         if (txinfo->status.rates[0].count == 1)
 416                 sta_info->stats[tid].ampdu_ack_len++;
 417
 418         if (!(txinfo->flags & IEEE80211_TX_STAT_ACK))
 419                 sta_info->stats[tid].req = true;
 420
 421         if (super->f.mac_control & cpu_to_le16(AR9170_TX_MAC_IMM_BA)) {
 422                 super->s.rix = sta_info->stats[tid].ampdu_len;
 423                 super->s.cnt = sta_info->stats[tid].ampdu_ack_len;
 424                 txinfo->flags |= IEEE80211_TX_STAT_AMPDU;
 425                 if (sta_info->stats[tid].req)
 426                         txinfo->flags |= IEEE80211_TX_STAT_AMPDU_NO_BACK;
 427
 428                 sta_info->stats[tid].clear = true;
 429         }
 430         spin_unlock_bh(&tid_info->lock);
 431
 432 out_rcu:
 433         rcu_read_unlock();
 434 }
 435
 436 void carl9170_tx_status(struct ar9170 *ar, struct sk_buff *skb,
 437                         const bool success)
 438 {
 439         struct ieee80211_tx_info *txinfo;
 440
 441         carl9170_tx_accounting_free(ar, skb);
 442
 443         txinfo = IEEE80211_SKB_CB(skb);
 444
 445         if (success)
 446                 txinfo->flags |= IEEE80211_TX_STAT_ACK;
 447         else
 448                 ar->tx_ack_failures++;
 449
 450         if (txinfo->flags & IEEE80211_TX_CTL_AMPDU)
 451                 carl9170_tx_status_process_ampdu(ar, skb, txinfo);
 452
 453         carl9170_tx_ps_unblock(ar, skb);
 454         carl9170_tx_put_skb(skb);
 455 }
 456
 457 /* This function may be called form any context */
 458 void carl9170_tx_callback(struct ar9170 *ar, struct sk_buff *skb)
 459 {
 460         struct ieee80211_tx_info *txinfo = IEEE80211_SKB_CB(skb);
 461
 462         atomic_dec(&ar->tx_total_pending);
 463
 464         if (txinfo->flags & IEEE80211_TX_CTL_AMPDU)
 465                 atomic_dec(&ar->tx_ampdu_upload);
 466
 467         if (carl9170_tx_put_skb(skb))
 468                 tasklet_hi_schedule(&ar->usb_tasklet);
 469 }
 470
 471 static struct sk_buff *carl9170_get_queued_skb(struct ar9170 *ar, u8 cookie,
 472                                                struct sk_buff_head *queue)
 473 {
 474         struct sk_buff *skb;
 475
 476         spin_lock_bh(&queue->lock);
 477         skb_queue_walk(queue, skb) {
 478                 struct _carl9170_tx_superframe *txc = (void *) skb->data;
 479
 480                 if (txc->s.cookie != cookie)
 481                         continue;
 482
 483                 __skb_unlink(skb, queue);
 484                 spin_unlock_bh(&queue->lock);
 485
 486                 carl9170_release_dev_space(ar, skb);
 487                 return skb;
 488         }
 489         spin_unlock_bh(&queue->lock);
 490
 491         return NULL;
 492 }
 493
 494 static void carl9170_tx_fill_rateinfo(struct ar9170 *ar, unsigned int rix,
 495         unsigned int tries, struct ieee80211_tx_info *txinfo)
 496 {
 497         unsigned int i;
 498
 499         for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
 500                 if (txinfo->status.rates[i].idx < 0)
 501                         break;
 502
 503                 if (i == rix) {
 504                         txinfo->status.rates[i].count = tries;
 505                         i++;
 506                         break;
 507                 }
 508         }
 509
 510         for (; i < IEEE80211_TX_MAX_RATES; i++) {
 511                 txinfo->status.rates[i].idx = -1;
 512                 txinfo->status.rates[i].count = 0;
 513         }
 514 }
 515
 516 static void carl9170_check_queue_stop_timeout(struct ar9170 *ar)
 517 {
 518         int i;
 519         struct sk_buff *skb;
 520         struct ieee80211_tx_info *txinfo;
 521         struct carl9170_tx_info *arinfo;
 522         bool restart = false;
 523
 524         for (i = 0; i < ar->hw->queues; i++) {
 525                 spin_lock_bh(&ar->tx_status[i].lock);
 526
 527                 skb = skb_peek(&ar->tx_status[i]);
 528
 529                 if (!skb)
 530                         goto next;
 531
 532                 txinfo = IEEE80211_SKB_CB(skb);
 533                 arinfo = (void *) txinfo->rate_driver_data;
 534
 535                 if (time_is_before_jiffies(arinfo->timeout +
 536                     msecs_to_jiffies(CARL9170_QUEUE_STUCK_TIMEOUT)) == true)
 537                         restart = true;
 538
 539 next:
 540                 spin_unlock_bh(&ar->tx_status[i].lock);
 541         }
 542
 543         if (restart) {
 544                 /*
 545                  * At least one queue has been stuck for long enough.
 546                  * Give the device a kick and hope it gets back to
 547                  * work.
 548                  *
 549                  * possible reasons may include:
 550                  *  - frames got lost/corrupted (bad connection to the device)
 551                  *  - stalled rx processing/usb controller hiccups
 552                  *  - firmware errors/bugs
 553                  *  - every bug you can think of.
 554                  *  - all bugs you can't...
 555                  *  - ...
 556                  */
 557                 carl9170_restart(ar, CARL9170_RR_STUCK_TX);
 558         }
 559 }
 560
 561 static void carl9170_tx_ampdu_timeout(struct ar9170 *ar)
 562 {
 563         struct carl9170_sta_tid *iter;
 564         struct sk_buff *skb;
 565         struct ieee80211_tx_info *txinfo;
 566         struct carl9170_tx_info *arinfo;
 567         struct ieee80211_sta *sta;
 568
 569         rcu_read_lock();
 570         list_for_each_entry_rcu(iter, &ar->tx_ampdu_list, list) {
 571                 if (iter->state < CARL9170_TID_STATE_IDLE)
 572                         continue;
 573
 574                 spin_lock_bh(&iter->lock);
 575                 skb = skb_peek(&iter->queue);
 576                 if (!skb)
 577                         goto unlock;
 578
 579                 txinfo = IEEE80211_SKB_CB(skb);
 580                 arinfo = (void *)txinfo->rate_driver_data;
 581                 if (time_is_after_jiffies(arinfo->timeout +
 582                     msecs_to_jiffies(CARL9170_QUEUE_TIMEOUT)))
 583                         goto unlock;
 584
 585                 sta = __carl9170_get_tx_sta(ar, skb);
 586                 if (WARN_ON(!sta))
 587                         goto unlock;
 588
 589                 ieee80211_stop_tx_ba_session(sta, iter->tid);
 590 unlock:
 591                 spin_unlock_bh(&iter->lock);
 592
 593         }
 594         rcu_read_unlock();
 595 }
 596
 597 void carl9170_tx_janitor(struct work_struct *work)
 598 {
 599         struct ar9170 *ar = container_of(work, struct ar9170,
 600                                          tx_janitor.work);
 601         if (!IS_STARTED(ar))
 602                 return;
 603
 604         ar->tx_janitor_last_run = jiffies;
 605
 606         carl9170_check_queue_stop_timeout(ar);
 607         carl9170_tx_ampdu_timeout(ar);
 608
 609         if (!atomic_read(&ar->tx_total_queued))
 610                 return;
 611
 612         ieee80211_queue_delayed_work(ar->hw, &ar->tx_janitor,
 613                 msecs_to_jiffies(CARL9170_TX_TIMEOUT));
 614 }
 615
 616 static void __carl9170_tx_process_status(struct ar9170 *ar,
 617         const uint8_t cookie, const uint8_t info)
 618 {
 619         struct sk_buff *skb;
 620         struct ieee80211_tx_info *txinfo;
 621         unsigned int r, t, q;
 622         bool success = true;
 623
 624         q = ar9170_qmap[info & CARL9170_TX_STATUS_QUEUE];
 625
 626         skb = carl9170_get_queued_skb(ar, cookie, &ar->tx_status[q]);
 627         if (!skb) {
 628                 /*
 629                  * We have lost the race to another thread.
 630                  */
 631
 632                 return ;
 633         }
 634
 635         txinfo = IEEE80211_SKB_CB(skb);
 636
 637         if (!(info & CARL9170_TX_STATUS_SUCCESS))
 638                 success = false;
 639
 640         r = (info & CARL9170_TX_STATUS_RIX) >> CARL9170_TX_STATUS_RIX_S;
 641         t = (info & CARL9170_TX_STATUS_TRIES) >> CARL9170_TX_STATUS_TRIES_S;
 642
 643         carl9170_tx_fill_rateinfo(ar, r, t, txinfo);
 644         carl9170_tx_status(ar, skb, success);
 645 }
 646
 647 void carl9170_tx_process_status(struct ar9170 *ar,
 648                                 const struct carl9170_rsp *cmd)
 649 {
 650         unsigned int i;
 651
 652         for (i = 0;  i < cmd->hdr.ext; i++) {
 653                 if (WARN_ON(i > ((cmd->hdr.len / 2) + 1))) {
 654                         print_hex_dump_bytes("UU:", DUMP_PREFIX_NONE,
 655                                              (void *) cmd, cmd->hdr.len + 4);
 656                         break;
 657                 }
 658
 659                 __carl9170_tx_process_status(ar, cmd->_tx_status[i].cookie,
 660                                              cmd->_tx_status[i].info);
 661         }
 662 }
 663
 664 static __le32 carl9170_tx_physet(struct ar9170 *ar,
 665         struct ieee80211_tx_info *info, struct ieee80211_tx_rate *txrate)
 666 {
 667         struct ieee80211_rate *rate = NULL;
 668         u32 power, chains;
 669         __le32 tmp;
 670
 671         tmp = cpu_to_le32(0);
 672
 673         if (txrate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
 674                 tmp |= cpu_to_le32(AR9170_TX_PHY_BW_40MHZ <<
 675                         AR9170_TX_PHY_BW_S);
 676         /* this works because 40 MHz is 2 and dup is 3 */
 677         if (txrate->flags & IEEE80211_TX_RC_DUP_DATA)
 678                 tmp |= cpu_to_le32(AR9170_TX_PHY_BW_40MHZ_DUP <<
 679                         AR9170_TX_PHY_BW_S);
 680
 681         if (txrate->flags & IEEE80211_TX_RC_SHORT_GI)
 682                 tmp |= cpu_to_le32(AR9170_TX_PHY_SHORT_GI);
 683
 684         if (txrate->flags & IEEE80211_TX_RC_MCS) {
 685                 u32 r = txrate->idx;
 686                 u8 *txpower;
 687
 688                 /* heavy clip control */
 689                 tmp |= cpu_to_le32((r & 0x7) <<
 690                         AR9170_TX_PHY_TX_HEAVY_CLIP_S);
 691
 692                 if (txrate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH) {
 693                         if (info->band == IEEE80211_BAND_5GHZ)
 694                                 txpower = ar->power_5G_ht40;
 695                         else
 696                                 txpower = ar->power_2G_ht40;
 697                 } else {
 698                         if (info->band == IEEE80211_BAND_5GHZ)
 699                                 txpower = ar->power_5G_ht20;
 700                         else
 701                                 txpower = ar->power_2G_ht20;
 702                 }
 703
 704                 power = txpower[r & 7];
 705
 706                 /* +1 dBm for HT40 */
 707                 if (txrate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
 708                         power += 2;
 709
 710                 r <<= AR9170_TX_PHY_MCS_S;
 711                 BUG_ON(r & ~AR9170_TX_PHY_MCS);
 712
 713                 tmp |= cpu_to_le32(r & AR9170_TX_PHY_MCS);
 714                 tmp |= cpu_to_le32(AR9170_TX_PHY_MOD_HT);
 715
 716                 /*
 717                  * green field preamble does not work.
 718                  *
 719                  * if (txrate->flags & IEEE80211_TX_RC_GREEN_FIELD)
 720                  * tmp |= cpu_to_le32(AR9170_TX_PHY_GREENFIELD);
 721                  */
 722         } else {
 723                 u8 *txpower;
 724                 u32 mod;
 725                 u32 phyrate;
 726                 u8 idx = txrate->idx;
 727
 728                 if (info->band != IEEE80211_BAND_2GHZ) {
 729                         idx += 4;
 730                         txpower = ar->power_5G_leg;
 731                         mod = AR9170_TX_PHY_MOD_OFDM;
 732                 } else {
 733                         if (idx < 4) {
 734                                 txpower = ar->power_2G_cck;
 735                                 mod = AR9170_TX_PHY_MOD_CCK;
 736                         } else {
 737                                 mod = AR9170_TX_PHY_MOD_OFDM;
 738                                 txpower = ar->power_2G_ofdm;
 739                         }
 740                 }
 741
 742                 rate = &__carl9170_ratetable[idx];
 743
 744                 phyrate = rate->hw_value & 0xF;
 745                 power = txpower[(rate->hw_value & 0x30) >> 4];
 746                 phyrate <<= AR9170_TX_PHY_MCS_S;
 747
 748                 tmp |= cpu_to_le32(mod);
 749                 tmp |= cpu_to_le32(phyrate);
 750
 751                 /*
 752                  * short preamble seems to be broken too.
 753                  *
 754                  * if (txrate->flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE)
 755                  *      tmp |= cpu_to_le32(AR9170_TX_PHY_SHORT_PREAMBLE);
 756                  */
 757         }
 758         power <<= AR9170_TX_PHY_TX_PWR_S;
 759         power &= AR9170_TX_PHY_TX_PWR;
 760         tmp |= cpu_to_le32(power);
 761
 762         /* set TX chains */
 763         if (ar->eeprom.tx_mask == 1) {
 764                 chains = AR9170_TX_PHY_TXCHAIN_1;
 765         } else {
 766                 chains = AR9170_TX_PHY_TXCHAIN_2;
 767
 768                 /* >= 36M legacy OFDM - use only one chain */
 769                 if (rate && rate->bitrate >= 360 &&
 770                     !(txrate->flags & IEEE80211_TX_RC_MCS))
 771                         chains = AR9170_TX_PHY_TXCHAIN_1;
 772         }
 773         tmp |= cpu_to_le32(chains << AR9170_TX_PHY_TXCHAIN_S);
 774
 775         return tmp;
 776 }
 777
 778 static bool carl9170_tx_rts_check(struct ar9170 *ar,
 779                                   struct ieee80211_tx_rate *rate,
 780                                   bool ampdu, bool multi)
 781 {
 782         switch (ar->erp_mode) {
 783         case CARL9170_ERP_AUTO:
 784                 if (ampdu)
 785                         break;
 786
 787         case CARL9170_ERP_MAC80211:
 788                 if (!(rate->flags & IEEE80211_TX_RC_USE_RTS_CTS))
 789                         break;
 790
 791         case CARL9170_ERP_RTS:
 792                 if (likely(!multi))
 793                         return true;
 794
 795         default:
 796                 break;
 797         }
 798
 799         return false;
 800 }
 801
 802 static bool carl9170_tx_cts_check(struct ar9170 *ar,
 803                                   struct ieee80211_tx_rate *rate)
 804 {
 805         switch (ar->erp_mode) {
 806         case CARL9170_ERP_AUTO:
 807         case CARL9170_ERP_MAC80211:
 808                 if (!(rate->flags & IEEE80211_TX_RC_USE_CTS_PROTECT))
 809                         break;
 810
 811         case CARL9170_ERP_CTS:
 812                 return true;
 813
 814         default:
 815                 break;
 816         }
 817
 818         return false;
 819 }
 820
 821 static int carl9170_tx_prepare(struct ar9170 *ar, struct sk_buff *skb)
 822 {
 823         struct ieee80211_hdr *hdr;
 824         struct _carl9170_tx_superframe *txc;
 825         struct carl9170_vif_info *cvif;
 826         struct ieee80211_tx_info *info;
 827         struct ieee80211_tx_rate *txrate;
 828         struct ieee80211_sta *sta;
 829         struct carl9170_tx_info *arinfo;
 830         unsigned int hw_queue;
 831         int i;
 832         __le16 mac_tmp;
 833         u16 len;
 834         bool ampdu, no_ack;
 835
 836         BUILD_BUG_ON(sizeof(*arinfo) > sizeof(info->rate_driver_data));
 837         BUILD_BUG_ON(sizeof(struct _carl9170_tx_superdesc) !=
 838                      CARL9170_TX_SUPERDESC_LEN);
 839
 840         BUILD_BUG_ON(sizeof(struct _ar9170_tx_hwdesc) !=
 841                      AR9170_TX_HWDESC_LEN);
 842
 843         BUILD_BUG_ON(IEEE80211_TX_MAX_RATES < CARL9170_TX_MAX_RATES);
 844
 845         BUILD_BUG_ON(AR9170_MAX_VIRTUAL_MAC >
 846                 ((CARL9170_TX_SUPER_MISC_VIF_ID >>
 847                  CARL9170_TX_SUPER_MISC_VIF_ID_S) + 1));
 848
 849         hw_queue = ar9170_qmap[carl9170_get_queue(ar, skb)];
 850
 851         hdr = (void *)skb->data;
 852         info = IEEE80211_SKB_CB(skb);
 853         len = skb->len;
 854
 855         /*
 856          * Note: If the frame was sent through a monitor interface,
 857          * the ieee80211_vif pointer can be NULL.
 858          */
 859         if (likely(info->control.vif))
 860                 cvif = (void *) info->control.vif->drv_priv;
 861         else
 862                 cvif = NULL;
 863
 864         sta = info->control.sta;
 865
 866         txc = (void *)skb_push(skb, sizeof(*txc));
 867         memset(txc, 0, sizeof(*txc));
 868
 869         SET_VAL(CARL9170_TX_SUPER_MISC_QUEUE, txc->s.misc, hw_queue);
 870
 871         if (likely(cvif))
 872                 SET_VAL(CARL9170_TX_SUPER_MISC_VIF_ID, txc->s.misc, cvif->id);
 873
 874         if (unlikely(info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM))
 875                 txc->s.misc |= CARL9170_TX_SUPER_MISC_CAB;
 876
 877         if (unlikely(info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ))
 878                 txc->s.misc |= CARL9170_TX_SUPER_MISC_ASSIGN_SEQ;
 879
 880         if (unlikely(ieee80211_is_probe_resp(hdr->frame_control)))
 881                 txc->s.misc |= CARL9170_TX_SUPER_MISC_FILL_IN_TSF;
 882
 883         mac_tmp = cpu_to_le16(AR9170_TX_MAC_HW_DURATION |
 884                               AR9170_TX_MAC_BACKOFF);
 885         mac_tmp |= cpu_to_le16((hw_queue << AR9170_TX_MAC_QOS_S) &
 886                                AR9170_TX_MAC_QOS);
 887
 888         no_ack = !!(info->flags & IEEE80211_TX_CTL_NO_ACK);
 889         if (unlikely(no_ack))
 890                 mac_tmp |= cpu_to_le16(AR9170_TX_MAC_NO_ACK);
 891
 892         if (info->control.hw_key) {
 893                 len += info->control.hw_key->icv_len;
 894
 895                 switch (info->control.hw_key->cipher) {
 896                 case WLAN_CIPHER_SUITE_WEP40:
 897                 case WLAN_CIPHER_SUITE_WEP104:
 898                 case WLAN_CIPHER_SUITE_TKIP:
 899                         mac_tmp |= cpu_to_le16(AR9170_TX_MAC_ENCR_RC4);
 900                         break;
 901                 case WLAN_CIPHER_SUITE_CCMP:
 902                         mac_tmp |= cpu_to_le16(AR9170_TX_MAC_ENCR_AES);
 903                         break;
 904                 default:
 905                         WARN_ON(1);
 906                         goto err_out;
 907                 }
 908         }
 909
 910         ampdu = !!(info->flags & IEEE80211_TX_CTL_AMPDU);
 911         if (ampdu) {
 912                 unsigned int density, factor;
 913
 914                 if (unlikely(!sta || !cvif))
 915                         goto err_out;
 916
 917                 factor = min_t(unsigned int, 1u, sta->ht_cap.ampdu_factor);
 918                 density = sta->ht_cap.ampdu_density;
 919
 920                 if (density) {
 921                         /*
 922                          * Watch out!
 923                          *
 924                          * Otus uses slightly different density values than
 925                          * those from the 802.11n spec.
 926                          */
 927
 928                         density = max_t(unsigned int, density + 1, 7u);
 929                 }
 930
 931                 SET_VAL(CARL9170_TX_SUPER_AMPDU_DENSITY,
 932                         txc->s.ampdu_settings, density);
 933
 934                 SET_VAL(CARL9170_TX_SUPER_AMPDU_FACTOR,
 935                         txc->s.ampdu_settings, factor);
 936
 937                 for (i = 0; i < CARL9170_TX_MAX_RATES; i++) {
 938                         txrate = &info->control.rates[i];
 939                         if (txrate->idx >= 0) {
 940                                 txc->s.ri[i] =
 941                                         CARL9170_TX_SUPER_RI_AMPDU;
 942
 943                                 if (WARN_ON(!(txrate->flags &
 944                                               IEEE80211_TX_RC_MCS))) {
 945                                         /*
 946                                          * Not sure if it's even possible
 947                                          * to aggregate non-ht rates with
 948                                          * this HW.
 949                                          */
 950                                         goto err_out;
 951                                 }
 952                                 continue;
 953                         }
 954
 955                         txrate->idx = 0;
 956                         txrate->count = ar->hw->max_rate_tries;
 957                 }
 958
 959                 mac_tmp |= cpu_to_le16(AR9170_TX_MAC_AGGR);
 960         }
 961
 962         /*
 963          * NOTE: For the first rate, the ERP & AMPDU flags are directly
 964          * taken from mac_control. For all fallback rate, the firmware
 965          * updates the mac_control flags from the rate info field.
 966          */
 967         for (i = 1; i < CARL9170_TX_MAX_RATES; i++) {
 968                 txrate = &info->control.rates[i];
 969                 if (txrate->idx < 0)
 970                         break;
 971
 972                 SET_VAL(CARL9170_TX_SUPER_RI_TRIES, txc->s.ri[i],
 973                         txrate->count);
 974
 975                 if (carl9170_tx_rts_check(ar, txrate, ampdu, no_ack))
 976                         txc->s.ri[i] |= (AR9170_TX_MAC_PROT_RTS <<
 977                                 CARL9170_TX_SUPER_RI_ERP_PROT_S);
 978                 else if (carl9170_tx_cts_check(ar, txrate))
 979                         txc->s.ri[i] |= (AR9170_TX_MAC_PROT_CTS <<
 980                                 CARL9170_TX_SUPER_RI_ERP_PROT_S);
 981
 982                 txc->s.rr[i - 1] = carl9170_tx_physet(ar, info, txrate);
 983         }
 984
 985         txrate = &info->control.rates[0];
 986         SET_VAL(CARL9170_TX_SUPER_RI_TRIES, txc->s.ri[0], txrate->count);
 987
 988         if (carl9170_tx_rts_check(ar, txrate, ampdu, no_ack))
 989                 mac_tmp |= cpu_to_le16(AR9170_TX_MAC_PROT_RTS);
 990         else if (carl9170_tx_cts_check(ar, txrate))
 991                 mac_tmp |= cpu_to_le16(AR9170_TX_MAC_PROT_CTS);
 992
 993         txc->s.len = cpu_to_le16(skb->len);
 994         txc->f.length = cpu_to_le16(len + FCS_LEN);
 995         txc->f.mac_control = mac_tmp;
 996         txc->f.phy_control = carl9170_tx_physet(ar, info, txrate);
 997
 998         arinfo = (void *)info->rate_driver_data;
 999         arinfo->timeout = jiffies;
1000         arinfo->ar = ar;
1001         kref_init(&arinfo->ref);
1002         return 0;
1003
1004 err_out:
1005         skb_pull(skb, sizeof(*txc));
1006         return -EINVAL;
1007 }
1008
1009 static void carl9170_set_immba(struct ar9170 *ar, struct sk_buff *skb)
1010 {
1011         struct _carl9170_tx_superframe *super;
1012
1013         super = (void *) skb->data;
1014         super->f.mac_control |= cpu_to_le16(AR9170_TX_MAC_IMM_BA);
1015 }
1016
1017 static void carl9170_set_ampdu_params(struct ar9170 *ar, struct sk_buff *skb)
1018 {
1019         struct _carl9170_tx_superframe *super;
1020         int tmp;
1021
1022         super = (void *) skb->data;
1023
1024         tmp = (super->s.ampdu_settings & CARL9170_TX_SUPER_AMPDU_DENSITY) <<
1025                 CARL9170_TX_SUPER_AMPDU_DENSITY_S;
1026
1027         /*
1028          * If you haven't noticed carl9170_tx_prepare has already filled
1029          * in all ampdu spacing & factor parameters.
1030          * Now it's the time to check whenever the settings have to be
1031          * updated by the firmware, or if everything is still the same.
1032          *
1033          * There's no sane way to handle different density values with
1034          * this hardware, so we may as well just do the compare in the
1035          * driver.
1036          */
1037
1038         if (tmp != ar->current_density) {
1039                 ar->current_density = tmp;
1040                 super->s.ampdu_settings |=
1041                         CARL9170_TX_SUPER_AMPDU_COMMIT_DENSITY;
1042         }
1043
1044         tmp = (super->s.ampdu_settings & CARL9170_TX_SUPER_AMPDU_FACTOR) <<
1045                 CARL9170_TX_SUPER_AMPDU_FACTOR_S;
1046
1047         if (tmp != ar->current_factor) {
1048                 ar->current_factor = tmp;
1049                 super->s.ampdu_settings |=
1050                         CARL9170_TX_SUPER_AMPDU_COMMIT_FACTOR;
1051         }
1052 }
1053
1054 static bool carl9170_tx_rate_check(struct ar9170 *ar, struct sk_buff *_dest,
1055                                    struct sk_buff *_src)
1056 {
1057         struct _carl9170_tx_superframe *dest, *src;
1058
1059         dest = (void *) _dest->data;
1060         src = (void *) _src->data;
1061
1062         /*
1063          * The mac80211 rate control algorithm expects that all MPDUs in
1064          * an AMPDU share the same tx vectors.
1065          * This is not really obvious right now, because the hardware
1066          * does the AMPDU setup according to its own rulebook.
1067          * Our nicely assembled, strictly monotonic increasing mpdu
1068          * chains will be broken up, mashed back together...
1069          */
1070
1071         return (dest->f.phy_control == src->f.phy_control);
1072 }
1073
1074 static void carl9170_tx_ampdu(struct ar9170 *ar)
1075 {
1076         struct sk_buff_head agg;
1077         struct carl9170_sta_tid *tid_info;
1078         struct sk_buff *skb, *first;
1079         unsigned int i = 0, done_ampdus = 0;
1080         u16 seq, queue, tmpssn;
1081
1082         atomic_inc(&ar->tx_ampdu_scheduler);
1083         ar->tx_ampdu_schedule = false;
1084
1085         if (atomic_read(&ar->tx_ampdu_upload))
1086                 return;
1087
1088         if (!ar->tx_ampdu_list_len)
1089                 return;
1090
1091         __skb_queue_head_init(&agg);
1092
1093         rcu_read_lock();
1094         tid_info = rcu_dereference(ar->tx_ampdu_iter);
1095         if (WARN_ON_ONCE(!tid_info)) {
1096                 rcu_read_unlock();
1097                 return;
1098         }
1099
1100 retry:
1101         list_for_each_entry_continue_rcu(tid_info, &ar->tx_ampdu_list, list) {
1102                 i++;
1103
1104                 if (tid_info->state < CARL9170_TID_STATE_PROGRESS)
1105                         continue;
1106
1107                 queue = TID_TO_WME_AC(tid_info->tid);
1108
1109                 spin_lock_bh(&tid_info->lock);
1110                 if (tid_info->state != CARL9170_TID_STATE_XMIT)
1111                         goto processed;
1112
1113                 tid_info->counter++;
1114                 first = skb_peek(&tid_info->queue);
1115                 tmpssn = carl9170_get_seq(first);
1116                 seq = tid_info->snx;
1117
1118                 if (unlikely(tmpssn != seq)) {
1119                         tid_info->state = CARL9170_TID_STATE_IDLE;
1120
1121                         goto processed;
1122                 }
1123
1124                 while ((skb = skb_peek(&tid_info->queue))) {
1125                         /* strict 0, 1, ..., n - 1, n frame sequence order */
1126                         if (unlikely(carl9170_get_seq(skb) != seq))
1127                                 break;
1128
1129                         /* don't upload more than AMPDU FACTOR allows. */
1130                         if (unlikely(SEQ_DIFF(tid_info->snx, tid_info->bsn) >=
1131                             (tid_info->max - 1)))
1132                                 break;
1133
1134                         if (!carl9170_tx_rate_check(ar, skb, first))
1135                                 break;
1136
1137                         atomic_inc(&ar->tx_ampdu_upload);
1138                         tid_info->snx = seq = SEQ_NEXT(seq);
1139                         __skb_unlink(skb, &tid_info->queue);
1140
1141                         __skb_queue_tail(&agg, skb);
1142
1143                         if (skb_queue_len(&agg) >= CARL9170_NUM_TX_AGG_MAX)
1144                                 break;
1145                 }
1146
1147                 if (skb_queue_empty(&tid_info->queue) ||
1148                     carl9170_get_seq(skb_peek(&tid_info->queue)) !=
1149                     tid_info->snx) {
1150                         /*
1151                          * stop TID, if A-MPDU frames are still missing,
1152                          * or whenever the queue is empty.
1153                          */
1154
1155                         tid_info->state = CARL9170_TID_STATE_IDLE;
1156                 }
1157                 done_ampdus++;
1158
1159 processed:
1160                 spin_unlock_bh(&tid_info->lock);
1161
1162                 if (skb_queue_empty(&agg))
1163                         continue;
1164
1165                 /* apply ampdu spacing & factor settings */
1166                 carl9170_set_ampdu_params(ar, skb_peek(&agg));
1167
1168                 /* set aggregation push bit */
1169                 carl9170_set_immba(ar, skb_peek_tail(&agg));
1170
1171                 spin_lock_bh(&ar->tx_pending[queue].lock);
1172                 skb_queue_splice_tail_init(&agg, &ar->tx_pending[queue]);
1173                 spin_unlock_bh(&ar->tx_pending[queue].lock);
1174                 ar->tx_schedule = true;
1175         }
1176         if ((done_ampdus++ == 0) && (i++ == 0))
1177                 goto retry;
1178
1179         rcu_assign_pointer(ar->tx_ampdu_iter, tid_info);
1180         rcu_read_unlock();
1181 }
1182
1183 static struct sk_buff *carl9170_tx_pick_skb(struct ar9170 *ar,
1184                                             struct sk_buff_head *queue)
1185 {
1186         struct sk_buff *skb;
1187         struct ieee80211_tx_info *info;
1188         struct carl9170_tx_info *arinfo;
1189
1190         BUILD_BUG_ON(sizeof(*arinfo) > sizeof(info->rate_driver_data));
1191
1192         spin_lock_bh(&queue->lock);
1193         skb = skb_peek(queue);
1194         if (unlikely(!skb))
1195                 goto err_unlock;
1196
1197         if (carl9170_alloc_dev_space(ar, skb))
1198                 goto err_unlock;
1199
1200         __skb_unlink(skb, queue);
1201         spin_unlock_bh(&queue->lock);
1202
1203         info = IEEE80211_SKB_CB(skb);
1204         arinfo = (void *) info->rate_driver_data;
1205
1206         arinfo->timeout = jiffies;
1207         return skb;
1208
1209 err_unlock:
1210         spin_unlock_bh(&queue->lock);
1211         return NULL;
1212 }
1213
1214 void carl9170_tx_drop(struct ar9170 *ar, struct sk_buff *skb)
1215 {
1216         struct _carl9170_tx_superframe *super;
1217         uint8_t q = 0;
1218
1219         ar->tx_dropped++;
1220
1221         super = (void *)skb->data;
1222         SET_VAL(CARL9170_TX_SUPER_MISC_QUEUE, q,
1223                 ar9170_qmap[carl9170_get_queue(ar, skb)]);
1224         __carl9170_tx_process_status(ar, super->s.cookie, q);
1225 }
1226
1227 static bool carl9170_tx_ps_drop(struct ar9170 *ar, struct sk_buff *skb)
1228 {
1229         struct ieee80211_sta *sta;
1230         struct carl9170_sta_info *sta_info;
1231
1232         rcu_read_lock();
1233         sta = __carl9170_get_tx_sta(ar, skb);
1234         if (!sta)
1235                 goto out_rcu;
1236
1237         sta_info = (void *) sta->drv_priv;
1238         if (unlikely(sta_info->sleeping)) {
1239                 struct ieee80211_tx_info *tx_info;
1240
1241                 rcu_read_unlock();
1242
1243                 tx_info = IEEE80211_SKB_CB(skb);
1244                 if (tx_info->flags & IEEE80211_TX_CTL_AMPDU)
1245                         atomic_dec(&ar->tx_ampdu_upload);
1246
1247                 tx_info->flags |= IEEE80211_TX_STAT_TX_FILTERED;
1248                 carl9170_tx_status(ar, skb, false);
1249                 return true;
1250         }
1251
1252 out_rcu:
1253         rcu_read_unlock();
1254         return false;
1255 }
1256
1257 static void carl9170_tx(struct ar9170 *ar)
1258 {
1259         struct sk_buff *skb;
1260         unsigned int i, q;
1261         bool schedule_garbagecollector = false;
1262
1263         ar->tx_schedule = false;
1264
1265         if (unlikely(!IS_STARTED(ar)))
1266                 return;
1267
1268         carl9170_usb_handle_tx_err(ar);
1269
1270         for (i = 0; i < ar->hw->queues; i++) {
1271                 while (!skb_queue_empty(&ar->tx_pending[i])) {
1272                         skb = carl9170_tx_pick_skb(ar, &ar->tx_pending[i]);
1273                         if (unlikely(!skb))
1274                                 break;
1275
1276                         if (unlikely(carl9170_tx_ps_drop(ar, skb)))
1277                                 continue;
1278
1279                         atomic_inc(&ar->tx_total_pending);
1280
1281                         q = __carl9170_get_queue(ar, i);
1282                         /*
1283                          * NB: tx_status[i] vs. tx_status[q],
1284                          * TODO: Move into pick_skb or alloc_dev_space.
1285                          */
1286                         skb_queue_tail(&ar->tx_status[q], skb);
1287
1288                         /*
1289                          * increase ref count to "2".
1290                          * Ref counting is the easiest way to solve the
1291                          * race between the urb's completion routine:
1292                          *      carl9170_tx_callback
1293                          * and wlan tx status functions:
1294                          *      carl9170_tx_status/janitor.
1295                          */
1296                         carl9170_tx_get_skb(skb);
1297
1298                         carl9170_usb_tx(ar, skb);
1299                         schedule_garbagecollector = true;
1300                 }
1301         }
1302
1303         if (!schedule_garbagecollector)
1304                 return;
1305
1306         ieee80211_queue_delayed_work(ar->hw, &ar->tx_janitor,
1307                 msecs_to_jiffies(CARL9170_TX_TIMEOUT));
1308 }
1309
1310 static bool carl9170_tx_ampdu_queue(struct ar9170 *ar,
1311         struct ieee80211_sta *sta, struct sk_buff *skb)
1312 {
1313         struct _carl9170_tx_superframe *super = (void *) skb->data;
1314         struct carl9170_sta_info *sta_info;
1315         struct carl9170_sta_tid *agg;
1316         struct sk_buff *iter;
1317         u16 tid, seq, qseq, off;
1318         bool run = false;
1319
1320         tid = carl9170_get_tid(skb);
1321         seq = carl9170_get_seq(skb);
1322         sta_info = (void *) sta->drv_priv;
1323
1324         rcu_read_lock();
1325         agg = rcu_dereference(sta_info->agg[tid]);
1326
1327         if (!agg)
1328                 goto err_unlock_rcu;
1329
1330         spin_lock_bh(&agg->lock);
1331         if (unlikely(agg->state < CARL9170_TID_STATE_IDLE))
1332                 goto err_unlock;
1333
1334         /* check if sequence is within the BA window */
1335         if (unlikely(!BAW_WITHIN(agg->bsn, CARL9170_BAW_BITS, seq)))
1336                 goto err_unlock;
1337
1338         if (WARN_ON_ONCE(!BAW_WITHIN(agg->snx, CARL9170_BAW_BITS, seq)))
1339                 goto err_unlock;
1340
1341         off = SEQ_DIFF(seq, agg->bsn);
1342         if (WARN_ON_ONCE(test_and_set_bit(off, agg->bitmap)))
1343                 goto err_unlock;
1344
1345         if (likely(BAW_WITHIN(agg->hsn, CARL9170_BAW_BITS, seq))) {
1346                 __skb_queue_tail(&agg->queue, skb);
1347                 agg->hsn = seq;
1348                 goto queued;
1349         }
1350
1351         skb_queue_reverse_walk(&agg->queue, iter) {
1352                 qseq = carl9170_get_seq(iter);
1353
1354                 if (BAW_WITHIN(qseq, CARL9170_BAW_BITS, seq)) {
1355                         __skb_queue_after(&agg->queue, iter, skb);
1356                         goto queued;
1357                 }
1358         }
1359
1360         __skb_queue_head(&agg->queue, skb);
1361 queued:
1362
1363         if (unlikely(agg->state != CARL9170_TID_STATE_XMIT)) {
1364                 if (agg->snx == carl9170_get_seq(skb_peek(&agg->queue))) {
1365                         agg->state = CARL9170_TID_STATE_XMIT;
1366                         run = true;
1367                 }
1368         }
1369
1370         spin_unlock_bh(&agg->lock);
1371         rcu_read_unlock();
1372
1373         return run;
1374
1375 err_unlock:
1376         spin_unlock_bh(&agg->lock);
1377
1378 err_unlock_rcu:
1379         rcu_read_unlock();
1380         super->f.mac_control &= ~cpu_to_le16(AR9170_TX_MAC_AGGR);
1381         carl9170_tx_status(ar, skb, false);
1382         ar->tx_dropped++;
1383         return false;
1384 }
1385
1386 void carl9170_op_tx(struct ieee80211_hw *hw, struct sk_buff *skb)
1387 {
1388         struct ar9170 *ar = hw->priv;
1389         struct ieee80211_tx_info *info;
1390         struct ieee80211_sta *sta;
1391         bool run;
1392
1393         if (unlikely(!IS_STARTED(ar)))
1394                 goto err_free;
1395
1396         info = IEEE80211_SKB_CB(skb);
1397         sta = info->control.sta;
1398
1399         if (unlikely(carl9170_tx_prepare(ar, skb)))
1400                 goto err_free;
1401
1402         carl9170_tx_accounting(ar, skb);
1403         /*
1404          * from now on, one has to use carl9170_tx_status to free
1405          * all ressouces which are associated with the frame.
1406          */
1407
1408         if (sta) {
1409                 struct carl9170_sta_info *stai = (void *) sta->drv_priv;
1410                 atomic_inc(&stai->pending_frames);
1411         }
1412
1413         if (info->flags & IEEE80211_TX_CTL_AMPDU) {
1414                 run = carl9170_tx_ampdu_queue(ar, sta, skb);
1415                 if (run)
1416                         carl9170_tx_ampdu(ar);
1417
1418         } else {
1419                 unsigned int queue = skb_get_queue_mapping(skb);
1420
1421                 skb_queue_tail(&ar->tx_pending[queue], skb);
1422         }
1423
1424         carl9170_tx(ar);
1425         return;
1426
1427 err_free:
1428         ar->tx_dropped++;
1429         dev_kfree_skb_any(skb);
1430 }
1431
1432 void carl9170_tx_scheduler(struct ar9170 *ar)
1433 {
1434
1435         if (ar->tx_ampdu_schedule)
1436                 carl9170_tx_ampdu(ar);
1437
1438         if (ar->tx_schedule)
1439                 carl9170_tx(ar);
1440 }