carlfw/src/wlan.c

   1 /*
   2  * carl9170 firmware - used by the ar9170 wireless device
   3  *
   4  * Interface to the WLAN part of the chip
   5  *
   6  * Copyright (c) 2000-2005 ZyDAS Technology Corporation
   7  * Copyright (c) 2007-2009 Atheros Communications, Inc.
   8  * Copyright    2009    Johannes Berg <johannes@sipsolutions.net>
   9  * Copyright 2009-2011  Christian Lamparter <chunkeey@googlemail.com>
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License along
  22  * with this program; if not, write to the Free Software Foundation, Inc.,
  23  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  24  */
  25
  26 #include "carl9170.h"
  27 #include "shared/phy.h"
  28 #include "hostif.h"
  29 #include "timer.h"
  30 #include "wl.h"
  31 #include "printf.h"
  32 #include "rf.h"
  33 #include "linux/ieee80211.h"
  34 #include "wol.h"
  35
  36 static void wlan_txunstuck(unsigned int queue)
  37 {
  38         set_wlan_txq_dma_addr(queue, ((uint32_t) fw.wlan.tx_queue[queue].head) | 1);
  39 }
  40
  41 #ifdef CONFIG_CARL9170FW_DMA_QUEUE_BUMP
  42 static void wlan_txupdate(unsigned int queue)
  43 {
  44         set_wlan_txq_dma_addr(queue, ((uint32_t) fw.wlan.tx_queue[queue].head));
  45 }
  46
  47 static void wlan_dma_bump(unsigned int qidx)
  48 {
  49         unsigned int offset = qidx;
  50         uint32_t status, trigger;
  51
  52         status = get(AR9170_MAC_REG_DMA_STATUS) >> 12;
  53         trigger = get(AR9170_MAC_REG_DMA_TRIGGER) >> 12;
  54
  55         while (offset != 0) {
  56                 status >>= 4;
  57                 trigger >>= 4;
  58                 offset--;
  59         }
  60
  61         status &= 0xf;
  62         trigger &= 0xf;
  63
  64         if ((trigger == 0xa) && (status == 0x8)) {
  65                 DBG("UNSTUCK");
  66                 wlan_txunstuck(qidx);
  67         } else {
  68                 DBG("UPDATE");
  69                 wlan_txupdate(qidx);
  70         }
  71 }
  72 #endif /* CONFIG_CARL9170FW_DMA_QUEUE_BUMP */
  73
  74 #ifdef CONFIG_CARL9170FW_DEBUG
  75 static void wlan_dump_queue(unsigned int qidx)
  76 {
  77
  78         struct dma_desc *desc;
  79         struct carl9170_tx_superframe *super;
  80         int entries = 0;
  81
  82         __for_each_desc(desc, &fw.wlan.tx_queue[qidx]) {
  83                 super = get_super(desc);
  84                 DBG("%d: %p s:%x c:%x tl:%x ds:%x n:%p l:%p ", entries, desc,
  85                     desc->status, desc->ctrl, desc->totalLen,
  86                     desc->dataSize, desc->nextAddr, desc->lastAddr);
  87
  88                 DBG("c:%x tr:%d ri:%d l:%x m:%x p:%x fc:%x",
  89                     super->s.cookie, super->s.cnt, super->s.rix,
  90                     super->f.hdr.length, super->f.hdr.mac.set,
  91                     (unsigned int) le32_to_cpu(super->f.hdr.phy.set),
  92                     super->f.data.i3e.frame_control);
  93
  94                 entries++;
  95         }
  96
  97         desc = get_wlan_txq_addr(qidx);
  98
  99         DBG("Queue: %d: te:%d td:%d h:%p c:%p t:%p",
 100             qidx, entries, queue_len(&fw.wlan.tx_queue[qidx]),
 101             fw.wlan.tx_queue[qidx].head,
 102             desc, fw.wlan.tx_queue[qidx].terminator);
 103
 104         DBG("HW: t:%x s:%x ac:%x c:%x",
 105             (unsigned int) get(AR9170_MAC_REG_DMA_TRIGGER),
 106             (unsigned int) get(AR9170_MAC_REG_DMA_STATUS),
 107             (unsigned int) get(AR9170_MAC_REG_AMPDU_COUNT),
 108             (unsigned int) get(AR9170_MAC_REG_DMA_TXQX_ADDR_CURR));
 109 }
 110 #endif /* CONFIG_CARL9170FW_DEBUG */
 111
 112 static void wlan_send_buffered_tx_status(void)
 113 {
 114         unsigned int len;
 115
 116         while (fw.wlan.tx_status_pending) {
 117                 len = min((unsigned int)fw.wlan.tx_status_pending,
 118                           CARL9170_RSP_TX_STATUS_NUM);
 119                 len = min(len, CARL9170_TX_STATUS_NUM - fw.wlan.tx_status_head_idx);
 120
 121                 /*
 122                  * rather than memcpy each individual request into a large buffer,
 123                  * we _splice_ them all together.
 124                  *
 125                  * The only downside is however that we have to be careful around
 126                  * the edges of the tx_status_cache.
 127                  *
 128                  * Note:
 129                  * Each tx_status is about 2 bytes. However every command package
 130                  * must have a size which is a multiple of 4.
 131                  */
 132
 133                 send_cmd_to_host((len * sizeof(struct carl9170_tx_status) + 3) & ~3,
 134                                  CARL9170_RSP_TXCOMP, len, (void *)
 135                                  &fw.wlan.tx_status_cache[fw.wlan.tx_status_head_idx]);
 136
 137                 fw.wlan.tx_status_pending -= len;
 138                 fw.wlan.tx_status_head_idx += len;
 139                 fw.wlan.tx_status_head_idx %= CARL9170_TX_STATUS_NUM;
 140         }
 141 }
 142
 143 static struct carl9170_tx_status *wlan_get_tx_status_buffer(void)
 144 {
 145         struct carl9170_tx_status *tmp;
 146
 147         tmp = &fw.wlan.tx_status_cache[fw.wlan.tx_status_tail_idx++];
 148         fw.wlan.tx_status_tail_idx %= CARL9170_TX_STATUS_NUM;
 149
 150         if (fw.wlan.tx_status_pending == CARL9170_TX_STATUS_NUM)
 151                 wlan_send_buffered_tx_status();
 152
 153         fw.wlan.tx_status_pending++;
 154
 155         return tmp;
 156 }
 157
 158 /* generate _aggregated_ tx_status for the host */
 159 void wlan_tx_complete(struct carl9170_tx_superframe *super,
 160                       bool txs)
 161 {
 162         struct carl9170_tx_status *status;
 163
 164         status = wlan_get_tx_status_buffer();
 165
 166         /*
 167          * The *unique* cookie and AC_ID is used by the driver for
 168          * frame lookup.
 169          */
 170         status->cookie = super->s.cookie;
 171         status->queue = super->s.queue;
 172         super->s.cookie = 0;
 173
 174         /*
 175          * This field holds the number of tries of the rate in
 176          * the rate index field (rix).
 177          */
 178         status->rix = super->s.rix;
 179         status->tries = super->s.cnt;
 180         status->success = (txs) ? 1 : 0;
 181 }
 182
 183 static bool wlan_tx_consume_retry(struct carl9170_tx_superframe *super)
 184 {
 185         /* check if this was the last possible retry with this rate */
 186         if (unlikely(super->s.cnt >= super->s.ri[super->s.rix].tries)) {
 187                 /* end of the road - indicate tx failure */
 188                 if (unlikely(super->s.rix == CARL9170_TX_MAX_RETRY_RATES))
 189                         return false;
 190
 191                 /* check if there are alternative rates available */
 192                 if (!super->s.rr[super->s.rix].set)
 193                         return false;
 194
 195                 /* try next retry rate */
 196                 super->f.hdr.phy.set = super->s.rr[super->s.rix].set;
 197
 198                 /* finally - mark the old rate as USED */
 199                 super->s.rix++;
 200
 201                 /* update MAC flags */
 202                 super->f.hdr.mac.erp_prot = super->s.ri[super->s.rix].erp_prot;
 203                 super->f.hdr.mac.ampdu = super->s.ri[super->s.rix].ampdu;
 204
 205                 /* reinitialize try counter */
 206                 super->s.cnt = 1;
 207         } else {
 208                 /* just increase retry counter */
 209                 super->s.cnt++;
 210         }
 211
 212         return true;
 213 }
 214
 215 static inline u16 get_tid(struct ieee80211_hdr *hdr)
 216 {
 217         return (ieee80211_get_qos_ctl(hdr))[0] & IEEE80211_QOS_CTL_TID_MASK;
 218 }
 219
 220 /* This function will only work on uint32_t-aligned pointers! */
 221 static bool same_hdr(const void *_d0, const void *_d1)
 222 {
 223         const uint32_t *d0 = _d0;
 224         const uint32_t *d1 = _d1;
 225
 226         /* BUG_ON((unsigned long)d0 & 3 || (unsigned long)d1 & 3)) */
 227         return !((d0[0] ^ d1[0]) |                      /* FC + DU */
 228                  (d0[1] ^ d1[1]) |                      /* addr1 */
 229                  (d0[2] ^ d1[2]) | (d0[3] ^ d1[3]) |    /* addr2 + addr3 */
 230                  (d0[4] ^ d1[4]));                      /* addr3 */
 231 }
 232
 233 static inline bool same_aggr(struct ieee80211_hdr *a, struct ieee80211_hdr *b)
 234 {
 235         return (get_tid(a) == get_tid(b)) || same_hdr(a, b);
 236 }
 237
 238 static void wlan_tx_ampdu_reset(unsigned int qidx)
 239 {
 240         fw.wlan.ampdu_prev[qidx] = NULL;
 241 }
 242
 243 static void wlan_tx_ampdu_end(unsigned int qidx)
 244 {
 245         struct carl9170_tx_superframe *ht_prev = fw.wlan.ampdu_prev[qidx];
 246
 247         if (ht_prev)
 248                 ht_prev->f.hdr.mac.ba_end = 1;
 249
 250         wlan_tx_ampdu_reset(qidx);
 251 }
 252
 253 static void wlan_tx_ampdu(struct carl9170_tx_superframe *super)
 254 {
 255         unsigned int qidx = super->s.queue;
 256         struct carl9170_tx_superframe *ht_prev = fw.wlan.ampdu_prev[qidx];
 257
 258         if (super->f.hdr.mac.ampdu) {
 259                 if (ht_prev &&
 260                     !same_aggr(&super->f.data.i3e, &ht_prev->f.data.i3e))
 261                         ht_prev->f.hdr.mac.ba_end = 1;
 262                 else
 263                         super->f.hdr.mac.ba_end = 0;
 264
 265                 fw.wlan.ampdu_prev[qidx] = super;
 266         } else {
 267                 wlan_tx_ampdu_end(qidx);
 268         }
 269 }
 270
 271 /* for all tries */
 272 static void __wlan_tx(struct dma_desc *desc)
 273 {
 274         struct carl9170_tx_superframe *super = get_super(desc);
 275
 276         if (unlikely(super->s.fill_in_tsf)) {
 277                 struct ieee80211_mgmt *mgmt = (void *) &super->f.data.i3e;
 278                 uint32_t *tsf = (uint32_t *) &mgmt->u.probe_resp.timestamp;
 279
 280                 /*
 281                  * Truth be told: this is a hack.
 282                  *
 283                  * The *real* TSF is definitely going to be higher/older.
 284                  * But this hardware emulation code is head and shoulders
 285                  * above anything a driver can possibly do.
 286                  *
 287                  * (even, if it's got an accurate atomic clock source).
 288                  */
 289
 290                 read_tsf(tsf);
 291         }
 292
 293         wlan_tx_ampdu(super);
 294
 295 #ifdef CONFIG_CARL9170FW_DEBUG
 296         BUG_ON(fw.phy.psm.state != CARL9170_PSM_WAKE);
 297 #endif /* CONFIG_CARL9170FW_DEBUG */
 298
 299         /* insert desc into the right queue */
 300         dma_put(&fw.wlan.tx_queue[super->s.queue], desc);
 301 }
 302
 303 static void wlan_assign_seq(struct ieee80211_hdr *hdr, unsigned int vif)
 304 {
 305         hdr->seq_ctrl &= cpu_to_le16(~IEEE80211_SCTL_SEQ);
 306         hdr->seq_ctrl |= cpu_to_le16(fw.wlan.sequence[vif]);
 307
 308         if (ieee80211_is_first_frag(hdr->seq_ctrl))
 309                 fw.wlan.sequence[vif] += 0x10;
 310 }
 311
 312 /* prepares frame for the first transmission */
 313 static void _wlan_tx(struct dma_desc *desc)
 314 {
 315         struct carl9170_tx_superframe *super = get_super(desc);
 316
 317         if (unlikely(super->s.assign_seq))
 318                 wlan_assign_seq(&super->f.data.i3e, super->s.vif_id);
 319
 320         if (unlikely(super->s.ampdu_commit_density)) {
 321                 set(AR9170_MAC_REG_AMPDU_DENSITY,
 322                     MOD_VAL(AR9170_MAC_AMPDU_DENSITY,
 323                             get(AR9170_MAC_REG_AMPDU_DENSITY),
 324                             super->s.ampdu_density));
 325         }
 326
 327         if (unlikely(super->s.ampdu_commit_factor)) {
 328                 set(AR9170_MAC_REG_AMPDU_FACTOR,
 329                     MOD_VAL(AR9170_MAC_AMPDU_FACTOR,
 330                             get(AR9170_MAC_REG_AMPDU_FACTOR),
 331                             8 << super->s.ampdu_factor));
 332         }
 333 }
 334
 335 /* propagate transmission status back to the driver */
 336 static bool wlan_tx_status(struct dma_queue *queue,
 337                            struct dma_desc *desc)
 338 {
 339         struct carl9170_tx_superframe *super = get_super(desc);
 340         unsigned int qidx = super->s.queue;
 341         bool txfail = false, success;
 342
 343         success = true;
 344
 345         /* update hangcheck */
 346         fw.wlan.last_super_num[qidx] = 0;
 347
 348         /*
 349          * Note:
 350          * There could be a corner case when the TXFAIL is set
 351          * even though the frame was properly ACKed by the peer:
 352          *   a BlockAckReq with the immediate policy will cause
 353          *   the receiving peer to produce a BlockACK unfortunately
 354          *   the MAC in this chip seems to be expecting a legacy
 355          *   ACK and marks the BAR as failed!
 356          */
 357
 358         if (!!(desc->ctrl & AR9170_CTRL_FAIL)) {
 359                 txfail = !!(desc->ctrl & AR9170_CTRL_TXFAIL);
 360
 361                 /* reset retry indicator flags */
 362                 desc->ctrl &= ~(AR9170_CTRL_TXFAIL | AR9170_CTRL_BAFAIL);
 363
 364                 /*
 365                  * Note: wlan_tx_consume_retry will override the old
 366                  * phy [CCK,OFDM, HT, BW20/40, MCS...] and mac vectors
 367                  * [AMPDU,RTS/CTS,...] therefore be careful when they
 368                  * are used.
 369                  */
 370                 if (wlan_tx_consume_retry(super)) {
 371                         /*
 372                          * retry for simple and aggregated 802.11 frames.
 373                          *
 374                          * Note: We must not mess up the original frame
 375                          * order.
 376                          */
 377
 378                         if (!super->f.hdr.mac.ampdu) {
 379                                 /*
 380                                  * 802.11 - 7.1.3.1.5.
 381                                  * set "Retry Field" for consecutive attempts
 382                                  *
 383                                  * Note: For AMPDU see:
 384                                  * 802.11n 9.9.1.6 "Retransmit Procedures"
 385                                  */
 386                                 super->f.data.i3e.frame_control |=
 387                                         cpu_to_le16(IEEE80211_FCTL_RETRY);
 388                         }
 389
 390                         if (txfail) {
 391                                 /* Normal TX Failure */
 392
 393                                 /* demise descriptor ownership back to the hardware */
 394                                 dma_rearm(desc);
 395
 396                                 /*
 397                                  * And this will get the queue going again.
 398                                  * To understand why: you have to get the HW
 399                                  * specs... But sadly I never saw them.
 400                                  */
 401                                 wlan_txunstuck(qidx);
 402
 403                                 /* abort cycle - this is necessary due to HW design */
 404                                 return false;
 405                         } else {
 406                                 /* (HT-) BlockACK failure */
 407
 408                                 /*
 409                                  * Unlink the failed attempt and put it into
 410                                  * the retry queue. The caller routine must
 411                                  * be aware of this so the frames don't get lost.
 412                                  */
 413
 414 #ifndef CONFIG_CARL9170FW_DEBUG
 415                                 dma_unlink_head(queue);
 416 #else /* CONFIG_CARL9170FW_DEBUG */
 417                                 BUG_ON(dma_unlink_head(queue) != desc);
 418 #endif /* CONFIG_CARL9170FW_DEBUG */
 419                                 dma_put(&fw.wlan.tx_retry, desc);
 420                                 return true;
 421                         }
 422                 } else {
 423                         /* out of frame attempts - discard frame */
 424                         success = false;
 425                 }
 426         }
 427
 428 #ifndef CONFIG_CARL9170FW_DEBUG
 429         dma_unlink_head(queue);
 430 #else /* CONFIG_CARL9170FW_DEBUG */
 431         BUG_ON(dma_unlink_head(queue) != desc);
 432 #endif /* CONFIG_CARL9170FW_DEBUG */
 433         if (txfail) {
 434                 /*
 435                  * Issue the queue bump,
 436                  * We need to do this in case this was the frame's last
 437                  * possible retry attempt and it unfortunately: it failed.
 438                  */
 439
 440                 wlan_txunstuck(qidx);
 441         }
 442
 443         unhide_super(desc);
 444
 445         if (unlikely(super == fw.wlan.fw_desc_data)) {
 446                 fw.wlan.fw_desc = desc;
 447                 fw.wlan.fw_desc_available = 1;
 448
 449                 if (fw.wlan.fw_desc_callback)
 450                         fw.wlan.fw_desc_callback(super, success);
 451
 452                 return true;
 453         }
 454
 455         if (unlikely(super->s.cab))
 456                 fw.wlan.cab_queue_len[super->s.vif_id]--;
 457
 458         wlan_tx_complete(super, success);
 459
 460         if (ieee80211_is_back_req(super->f.data.i3e.frame_control)) {
 461                 fw.wlan.queued_bar--;
 462         }
 463
 464         /* recycle freed descriptors */
 465         dma_reclaim(&fw.pta.down_queue, desc);
 466         down_trigger();
 467         return true;
 468 }
 469
 470 static void handle_tx_completion(void)
 471 {
 472         struct dma_desc *desc;
 473         int i;
 474
 475         for (i = AR9170_TXQ_SPECIAL; i >= AR9170_TXQ0; i--) {
 476                 __while_desc_bits(desc, &fw.wlan.tx_queue[i], AR9170_OWN_BITS_SW) {
 477                         if (!wlan_tx_status(&fw.wlan.tx_queue[i], desc)) {
 478                                 /* termination requested. */
 479                                 break;
 480                         }
 481                 }
 482
 483                 wlan_tx_ampdu_reset(i);
 484
 485                 for_each_desc(desc, &fw.wlan.tx_retry)
 486                         __wlan_tx(desc);
 487
 488                 wlan_tx_ampdu_end(i);
 489                 if (!queue_empty(&fw.wlan.tx_queue[i]))
 490                         wlan_trigger(BIT(i));
 491         }
 492 }
 493
 494 void __hot wlan_tx(struct dma_desc *desc)
 495 {
 496         struct carl9170_tx_superframe *super = DESC_PAYLOAD(desc);
 497
 498         if (ieee80211_is_back_req(super->f.data.i3e.frame_control)) {
 499                 fw.wlan.queued_bar++;
 500         }
 501
 502         /* initialize rate control struct */
 503         super->s.rix = 0;
 504         super->s.cnt = 1;
 505         hide_super(desc);
 506
 507         if (unlikely(super->s.cab)) {
 508                 fw.wlan.cab_queue_len[super->s.vif_id]++;
 509                 dma_put(&fw.wlan.cab_queue[super->s.vif_id], desc);
 510                 return;
 511         }
 512
 513         _wlan_tx(desc);
 514         __wlan_tx(desc);
 515         wlan_trigger(BIT(super->s.queue));
 516 }
 517
 518 void wlan_tx_fw(struct carl9170_tx_superdesc *super, fw_desc_callback_t cb)
 519 {
 520         if (!fw.wlan.fw_desc_available)
 521                 return;
 522
 523         fw.wlan.fw_desc_available = 0;
 524
 525         /* Format BlockAck */
 526         fw.wlan.fw_desc->ctrl = AR9170_CTRL_FS_BIT | AR9170_CTRL_LS_BIT;
 527         fw.wlan.fw_desc->status = AR9170_OWN_BITS_SW;
 528
 529         fw.wlan.fw_desc->totalLen = fw.wlan.fw_desc->dataSize = super->len;
 530         fw.wlan.fw_desc_data = fw.wlan.fw_desc->dataAddr = super;
 531         fw.wlan.fw_desc->nextAddr = fw.wlan.fw_desc->lastAddr =
 532                 fw.wlan.fw_desc;
 533         fw.wlan.fw_desc_callback = cb;
 534         wlan_tx(fw.wlan.fw_desc);
 535 }
 536
 537 static void wlan_send_buffered_ba(void)
 538 {
 539         struct carl9170_tx_ba_superframe *baf = &dma_mem.reserved.ba.ba;
 540         struct ieee80211_ba *ba = (struct ieee80211_ba *) &baf->f.ba;
 541         struct carl9170_bar_ctx *ctx;
 542
 543         if (likely(!fw.wlan.queued_ba))
 544                 return;
 545
 546         /* there's no point to continue when the ba_desc is not available. */
 547         if (!fw.wlan.fw_desc_available)
 548                 return;
 549
 550         ctx = &fw.wlan.ba_cache[fw.wlan.ba_head_idx];
 551         fw.wlan.ba_head_idx++;
 552         fw.wlan.ba_head_idx %= CONFIG_CARL9170FW_BACK_REQS_NUM;
 553         fw.wlan.queued_ba--;
 554
 555         baf->s.len = sizeof(struct carl9170_tx_superdesc) +
 556                      sizeof(struct ar9170_tx_hwdesc) +
 557                      sizeof(struct ieee80211_ba);
 558         baf->s.ri[0].tries = 1;
 559         baf->s.cookie = 0;
 560         baf->s.queue = AR9170_TXQ_VO;
 561         baf->f.hdr.length = sizeof(struct ieee80211_ba) + FCS_LEN;
 562
 563         baf->f.hdr.mac.no_ack = 1;
 564
 565         baf->f.hdr.phy.modulation = 1; /* OFDM */
 566         baf->f.hdr.phy.tx_power = 34; /* 17 dBm */
 567         baf->f.hdr.phy.chains = 1;
 568         baf->f.hdr.phy.mcs = AR9170_TXRX_PHY_RATE_OFDM_6M;
 569
 570         /* format outgoing BA */
 571         ba->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_BACK);
 572         ba->duration = cpu_to_le16(0);
 573
 574         /* the BAR contains all necessary MACs. All we need is to swap them */
 575         memcpy(ba->ra, ctx->ta, 6);
 576         memcpy(ba->ta, ctx->ra, 6);
 577
 578         /*
 579          * Unfortunately, we cannot look into the hardware's scoreboard.
 580          * Therefore we have to proceed as described in 802.11n 9.10.7.5
 581          * and send a null BlockAck.
 582          */
 583         memset(ba->bitmap, 0x0, sizeof(ba->bitmap));
 584
 585         /*
 586          * Both, the original firmare and ath9k set the NO ACK flag in
 587          * the BA Ack Policy subfield.
 588          */
 589         ba->control = ctx->control | cpu_to_le16(1);
 590         ba->start_seq_num = ctx->start_seq_num;
 591         wlan_tx_fw(&baf->s, NULL);
 592 }
 593
 594 static struct carl9170_bar_ctx *wlan_get_bar_cache_buffer(void)
 595 {
 596         struct carl9170_bar_ctx *tmp;
 597
 598         tmp = &fw.wlan.ba_cache[fw.wlan.ba_tail_idx];
 599         fw.wlan.ba_tail_idx++;
 600         fw.wlan.ba_tail_idx %= CONFIG_CARL9170FW_BACK_REQS_NUM;
 601         if (fw.wlan.queued_ba < CONFIG_CARL9170FW_BACK_REQS_NUM)
 602                 fw.wlan.queued_ba++;
 603
 604         return tmp;
 605 }
 606
 607 static void handle_bar(struct dma_desc *desc __unused, struct ieee80211_hdr *hdr,
 608                        unsigned int len, unsigned int mac_err)
 609 {
 610         struct ieee80211_bar *bar;
 611         struct carl9170_bar_ctx *ctx;
 612
 613         if (unlikely(mac_err)) {
 614                 /*
 615                  * This check does a number of things:
 616                  * 1. checks if the frame is in good nick
 617                  * 2. checks if the RA (MAC) matches
 618                  */
 619                 return ;
 620         }
 621
 622         if (unlikely(len < (sizeof(struct ieee80211_bar) + FCS_LEN))) {
 623                 /*
 624                  * Sneaky, corrupted BARs... but not with us!
 625                  */
 626
 627                 return ;
 628         }
 629
 630         bar = (void *) hdr;
 631
 632         if ((bar->control & cpu_to_le16(IEEE80211_BAR_CTRL_MULTI_TID)) ||
 633             !(bar->control & cpu_to_le16(IEEE80211_BAR_CTRL_CBMTID_COMPRESSED_BA))) {
 634                 /* not implemented yet */
 635
 636                 return ;
 637         }
 638
 639         ctx = wlan_get_bar_cache_buffer();
 640
 641         memcpy(ctx->ra, bar->ra, 6);
 642         memcpy(ctx->ta, bar->ta, 6);
 643         ctx->control = bar->control;
 644         ctx->start_seq_num = bar->start_seq_num;
 645 }
 646
 647 static void wlan_check_rx_overrun(void)
 648 {
 649         uint32_t overruns, total;
 650
 651         fw.tally.rx_total += total = get(AR9170_MAC_REG_RX_TOTAL);
 652         fw.tally.rx_overrun += overruns = get(AR9170_MAC_REG_RX_OVERRUN);
 653         if (unlikely(overruns)) {
 654                 if (overruns == total) {
 655                         DBG("RX Overrun");
 656                         fw.wlan.mac_reset++;
 657                 }
 658
 659                 wlan_trigger(AR9170_DMA_TRIGGER_RXQ);
 660         }
 661 }
 662
 663 static unsigned int wlan_rx_filter(struct dma_desc *desc)
 664 {
 665         struct ieee80211_hdr *hdr;
 666         unsigned int data_len;
 667         unsigned int rx_filter;
 668         unsigned int mac_err;
 669
 670         data_len = ar9170_get_rx_mpdu_len(desc);
 671         mac_err = ar9170_get_rx_macstatus_error(desc);
 672
 673 #define AR9170_RX_ERROR_BAD (AR9170_RX_ERROR_FCS | AR9170_RX_ERROR_PLCP)
 674
 675         if (unlikely(data_len < (4 + 6 + FCS_LEN) ||
 676             desc->totalLen > CONFIG_CARL9170FW_RX_FRAME_LEN) ||
 677             mac_err & AR9170_RX_ERROR_BAD) {
 678                 /*
 679                  * This frame is too damaged to do anything
 680                  * useful with it.
 681                  */
 682
 683                 return CARL9170_RX_FILTER_BAD;
 684         }
 685
 686         rx_filter = 0;
 687         if (mac_err & AR9170_RX_ERROR_WRONG_RA)
 688                 rx_filter |= CARL9170_RX_FILTER_OTHER_RA;
 689
 690         if (mac_err & AR9170_RX_ERROR_DECRYPT)
 691                 rx_filter |= CARL9170_RX_FILTER_DECRY_FAIL;
 692
 693         hdr = ar9170_get_rx_i3e(desc);
 694         if (likely(ieee80211_is_data(hdr->frame_control))) {
 695                 rx_filter |= CARL9170_RX_FILTER_DATA;
 696         } else if (ieee80211_is_ctl(hdr->frame_control)) {
 697                 switch (le16_to_cpu(hdr->frame_control) & IEEE80211_FCTL_STYPE) {
 698                 case IEEE80211_STYPE_BACK_REQ:
 699                         handle_bar(desc, hdr, data_len, mac_err);
 700                         rx_filter |= CARL9170_RX_FILTER_CTL_BACKR;
 701                         break;
 702                 case IEEE80211_STYPE_PSPOLL:
 703                         rx_filter |= CARL9170_RX_FILTER_CTL_PSPOLL;
 704                         break;
 705                 case IEEE80211_STYPE_BACK:
 706                         if (fw.wlan.queued_bar) {
 707                                 /*
 708                                  * Don't filter block acks when the application
 709                                  * has queued BARs. This is because the firmware
 710                                  * can't do the accouting and the application
 711                                  * has to sort out if the BA belongs to any BARs.
 712                                  */
 713                                 break;
 714                         }
 715                         /* otherwise fall through */
 716                 default:
 717                         rx_filter |= CARL9170_RX_FILTER_CTL_OTHER;
 718                         break;
 719                 }
 720         } else {
 721                 /* ieee80211_is_mgmt */
 722                 rx_filter |= CARL9170_RX_FILTER_MGMT;
 723         }
 724
 725         if (unlikely(fw.suspend_mode == CARL9170_HOST_SUSPENDED)) {
 726                 wol_rx(rx_filter, hdr, min(data_len,
 727                         (unsigned int)AR9170_BLOCK_SIZE));
 728         }
 729
 730 #undef AR9170_RX_ERROR_BAD
 731
 732         return rx_filter;
 733 }
 734
 735 static void handle_rx(void)
 736 {
 737         struct dma_desc *desc;
 738
 739         for_each_desc_not_bits(desc, &fw.wlan.rx_queue, AR9170_OWN_BITS_HW) {
 740                 if (!(wlan_rx_filter(desc) & fw.wlan.rx_filter)) {
 741                         dma_put(&fw.pta.up_queue, desc);
 742                         up_trigger();
 743                 } else {
 744                         dma_reclaim(&fw.wlan.rx_queue, desc);
 745                         wlan_trigger(AR9170_DMA_TRIGGER_RXQ);
 746                 }
 747         }
 748 }
 749
 750 void wlan_cab_flush_queue(const unsigned int vif)
 751 {
 752         struct dma_queue *cab_queue = &fw.wlan.cab_queue[vif];
 753         struct dma_desc *desc;
 754
 755         /* move queued frames into the main tx queues */
 756         for_each_desc(desc, cab_queue) {
 757                 struct carl9170_tx_superframe *super = get_super(desc);
 758                 if (!queue_empty(cab_queue)) {
 759                         /*
 760                          * Set MOREDATA flag for all,
 761                          * but the last queued frame.
 762                          * see: 802.11-2007 11.2.1.5 f)
 763                          *
 764                          * This is actually the reason to why
 765                          * we need to prevent the reentry.
 766                          */
 767
 768                         super->f.data.i3e.frame_control |=
 769                                 cpu_to_le16(IEEE80211_FCTL_MOREDATA);
 770                 } else {
 771                         super->f.data.i3e.frame_control &=
 772                                 cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
 773                 }
 774
 775                 /* ready to roll! */
 776                 _wlan_tx(desc);
 777                 __wlan_tx(desc);
 778                 wlan_trigger(BIT(super->s.queue));
 779         }
 780 }
 781
 782 static uint8_t *beacon_find_ie(uint8_t ie, void *addr,
 783                                const unsigned int len)
 784 {
 785         struct ieee80211_mgmt *mgmt = addr;
 786         uint8_t *pos, *end;
 787
 788         pos = mgmt->u.beacon.variable;
 789         end = (uint8_t *) ((unsigned long)mgmt + (len - FCS_LEN));
 790         while (pos < end) {
 791                 if (pos + 2 + pos[1] > end)
 792                         return NULL;
 793
 794                 if (pos[0] == ie)
 795                         return pos;
 796
 797                 pos += pos[1] + 2;
 798         }
 799
 800         return NULL;
 801 }
 802
 803 void wlan_modify_beacon(const unsigned int vif,
 804         const unsigned int addr, const unsigned int len)
 805 {
 806         uint8_t *_ie;
 807         struct ieee80211_tim_ie *ie;
 808
 809         _ie = beacon_find_ie(WLAN_EID_TIM, (void *)addr, len);
 810         if (likely(_ie)) {
 811                 ie = (struct ieee80211_tim_ie *) &_ie[2];
 812
 813                 if (!queue_empty(&fw.wlan.cab_queue[vif]) && (ie->dtim_count == 0)) {
 814                         /* schedule DTIM transfer */
 815                         fw.wlan.cab_flush_trigger[vif] = CARL9170_CAB_TRIGGER_ARMED;
 816                 } else if ((fw.wlan.cab_queue_len[vif] == 0) && (fw.wlan.cab_flush_trigger[vif])) {
 817                         /* undo all chances to the beacon structure */
 818                         ie->bitmap_ctrl &= ~0x1;
 819                         fw.wlan.cab_flush_trigger[vif] = CARL9170_CAB_TRIGGER_EMPTY;
 820                 }
 821
 822                 /* Triggered by CARL9170_CAB_TRIGGER_ARMED || CARL9170_CAB_TRIGGER_DEFER */
 823                 if (fw.wlan.cab_flush_trigger[vif]) {
 824                         /* Set the almighty Multicast Traffic Indication Bit. */
 825                         ie->bitmap_ctrl |= 0x1;
 826                 }
 827         }
 828
 829         /*
 830          * Ideally, the sequence number should be assigned by the TX arbiter
 831          * hardware. But AFAIK that's not possible, so we have to go for the
 832          * next best thing and write it into the beacon fifo during the open
 833          * beacon update window.
 834          */
 835
 836         wlan_assign_seq((struct ieee80211_hdr *)addr, vif);
 837 }
 838
 839 static void wlan_send_buffered_cab(void)
 840 {
 841         unsigned int i;
 842
 843         for (i = 0; i < CARL9170_INTF_NUM; i++) {
 844                 if (unlikely(fw.wlan.cab_flush_trigger[i] == CARL9170_CAB_TRIGGER_ARMED)) {
 845                         /*
 846                          * This is hardcoded into carl9170usb driver.
 847                          *
 848                          * The driver must set the PRETBTT event to beacon_interval -
 849                          * CARL9170_PRETBTT_KUS (usually 6) Kus.
 850                          *
 851                          * But still, we can only do so much about 802.11-2007 9.3.2.1 &
 852                          * 11.2.1.6. Let's hope the current solution is adequate enough.
 853                          */
 854
 855                         if (is_after_msecs(fw.wlan.cab_flush_time, (CARL9170_TBTT_DELTA))) {
 856                                 wlan_cab_flush_queue(i);
 857
 858                                 /*
 859                                  * This prevents the code from sending new BC/MC frames
 860                                  * which were queued after the previous buffered traffic
 861                                  * has been sent out... They will have to wait until the
 862                                  * next DTIM beacon comes along.
 863                                  */
 864                                 fw.wlan.cab_flush_trigger[i] = CARL9170_CAB_TRIGGER_DEFER;
 865                         }
 866                 }
 867
 868         }
 869 }
 870
 871 static void handle_beacon_config(void)
 872 {
 873         uint32_t bcn_count;
 874
 875         bcn_count = get(AR9170_MAC_REG_BCN_COUNT);
 876         send_cmd_to_host(4, CARL9170_RSP_BEACON_CONFIG, 0x00,
 877                          (uint8_t *) &bcn_count);
 878 }
 879
 880 static void handle_pretbtt(void)
 881 {
 882         fw.wlan.cab_flush_time = get_clock_counter();
 883
 884 #ifdef CONFIG_CARL9170FW_RADIO_FUNCTIONS
 885         rf_psm();
 886
 887         send_cmd_to_host(4, CARL9170_RSP_PRETBTT, 0x00,
 888                          (uint8_t *) &fw.phy.psm.state);
 889 #endif /* CONFIG_CARL9170FW_RADIO_FUNCTIONS */
 890 }
 891
 892 static void handle_atim(void)
 893 {
 894         send_cmd_to_host(0, CARL9170_RSP_ATIM, 0x00, NULL);
 895 }
 896
 897 #ifdef CONFIG_CARL9170FW_DEBUG
 898 static void handle_qos(void)
 899 {
 900         /*
 901          * What is the QoS Bit used for?
 902          * Is it only an indicator for TXOP & Burst, or
 903          * should we do something here?
 904          */
 905 }
 906
 907 static void handle_radar(void)
 908 {
 909         send_cmd_to_host(0, CARL9170_RSP_RADAR, 0x00, NULL);
 910 }
 911 #endif /* CONFIG_CARL9170FW_DEBUG */
 912
 913 static void wlan_janitor(void)
 914 {
 915         wlan_send_buffered_cab();
 916
 917         wlan_send_buffered_tx_status();
 918
 919         wlan_send_buffered_ba();
 920
 921         wol_janitor();
 922 }
 923
 924 void handle_wlan(void)
 925 {
 926         uint32_t intr;
 927
 928         intr = get(AR9170_MAC_REG_INT_CTRL);
 929         /* ACK Interrupt */
 930         set(AR9170_MAC_REG_INT_CTRL, intr);
 931
 932 #define HANDLER(intr, flag, func)                       \
 933         do {                                            \
 934                 if ((intr & flag) != 0) {               \
 935                         func();                         \
 936                 }                                       \
 937         } while (0)
 938
 939         intr |= fw.wlan.soft_int;
 940         fw.wlan.soft_int = 0;
 941
 942         HANDLER(intr, AR9170_MAC_INT_PRETBTT, handle_pretbtt);
 943
 944         HANDLER(intr, AR9170_MAC_INT_ATIM, handle_atim);
 945
 946         HANDLER(intr, AR9170_MAC_INT_RXC, handle_rx);
 947
 948         HANDLER(intr, (AR9170_MAC_INT_TXC | AR9170_MAC_INT_RETRY_FAIL),
 949                 handle_tx_completion);
 950
 951 #ifdef CONFIG_CARL9170FW_DEBUG
 952         HANDLER(intr, AR9170_MAC_INT_QOS, handle_qos);
 953
 954         HANDLER(intr, AR9170_MAC_INT_RADAR, handle_radar);
 955 #endif /* CONFIG_CARL9170FW_DEBUG */
 956
 957         HANDLER(intr, AR9170_MAC_INT_CFG_BCN, handle_beacon_config);
 958
 959         if (unlikely(intr))
 960                 DBG("Unhandled Interrupt %x\n", (unsigned int) intr);
 961
 962         wlan_janitor();
 963
 964 #undef HANDLER
 965 }
 966
 967 enum {
 968         CARL9170FW_TX_MAC_BUMP = 4,
 969         CARL9170FW_TX_MAC_DEBUG = 6,
 970         CARL9170FW_TX_MAC_RESET = 7,
 971 };
 972
 973 static void wlan_check_hang(void)
 974 {
 975         struct dma_desc *desc;
 976         int i;
 977
 978         for (i = AR9170_TXQ_SPECIAL; i >= AR9170_TXQ0; i--) {
 979                 if (queue_empty(&fw.wlan.tx_queue[i])) {
 980                         /* Nothing to do here... move along */
 981                         continue;
 982                 }
 983
 984                 /* fetch the current DMA queue position */
 985                 desc = (struct dma_desc *)get_wlan_txq_addr(i);
 986
 987                 /* Stuck frame detection */
 988                 if (unlikely(DESC_PAYLOAD(desc) == fw.wlan.last_super[i])) {
 989                         fw.wlan.last_super_num[i]++;
 990
 991                         if (unlikely(fw.wlan.last_super_num[i] >= CARL9170FW_TX_MAC_RESET)) {
 992                                 /*
 993                                  * schedule MAC reset (aka OFF/ON => dead)
 994                                  *
 995                                  * This will almost certainly kill
 996                                  * the device for good, but it's the
 997                                  * recommended thing to do...
 998                                  */
 999
1000                                 fw.wlan.mac_reset++;
1001                         }
1002
1003 #ifdef CONFIG_CARL9170FW_DEBUG
1004                         if (unlikely(fw.wlan.last_super_num[i] >= CARL9170FW_TX_MAC_DEBUG)) {
1005                                 /*
1006                                  * Sigh, the queue is almost certainly
1007                                  * dead. Dump the queue content to the
1008                                  * user, maybe we find out why it got
1009                                  * so stuck.
1010                                  */
1011
1012                                 wlan_dump_queue(i);
1013                         }
1014 #endif /* CONFIG_CARL9170FW_DEBUG */
1015
1016 #ifdef CONFIG_CARL9170FW_DMA_QUEUE_BUMP
1017                         if (unlikely(fw.wlan.last_super_num[i] >= CARL9170FW_TX_MAC_BUMP)) {
1018                                 /*
1019                                  * Hrrm, bump the queue a bit.
1020                                  * maybe this will get it going again.
1021                                  */
1022
1023                                 wlan_dma_bump(i);
1024                                 wlan_trigger(BIT(i));
1025                         }
1026 #endif /* CONFIG_CARL9170FW_DMA_QUEUE_BUMP */
1027                 } else {
1028                         /* Nothing stuck */
1029                         fw.wlan.last_super[i] = DESC_PAYLOAD(desc);
1030                         fw.wlan.last_super_num[i] = 0;
1031                 }
1032         }
1033 }
1034
1035 #ifdef CONFIG_CARL9170FW_FW_MAC_RESET
1036 /*
1037  * NB: Resetting the MAC is a two-edged sword.
1038  * On most occasions, it does what it is supposed to do.
1039  * But there is a chance that this will make it
1040  * even worse and the radio dies silently.
1041  */
1042 static void wlan_mac_reset(void)
1043 {
1044         uint32_t val;
1045         uint32_t agg_wait_counter;
1046         uint32_t agg_density;
1047         uint32_t bcn_start_addr;
1048         uint32_t rctl, rcth;
1049         uint32_t cam_mode;
1050         uint32_t ack_power;
1051         uint32_t rts_cts_tpc;
1052         uint32_t rts_cts_rate;
1053         int i;
1054
1055 #ifdef CONFIG_CARL9170FW_RADIO_FUNCTIONS
1056         uint32_t rx_BB;
1057 #endif /* CONFIG_CARL9170FW_RADIO_FUNCTIONS */
1058
1059 #ifdef CONFIG_CARL9170FW_NOISY_MAC_RESET
1060         INFO("MAC RESET");
1061 #endif /* CONFIG_CARL9170FW_NOISY_MAC_RESET */
1062
1063         /* Save aggregation parameters */
1064         agg_wait_counter = get(AR9170_MAC_REG_AMPDU_FACTOR);
1065         agg_density = get(AR9170_MAC_REG_AMPDU_DENSITY);
1066
1067         bcn_start_addr = get(AR9170_MAC_REG_BCN_ADDR);
1068
1069         cam_mode = get(AR9170_MAC_REG_CAM_MODE);
1070         rctl = get(AR9170_MAC_REG_CAM_ROLL_CALL_TBL_L);
1071         rcth = get(AR9170_MAC_REG_CAM_ROLL_CALL_TBL_H);
1072
1073         ack_power = get(AR9170_MAC_REG_ACK_TPC);
1074         rts_cts_tpc = get(AR9170_MAC_REG_RTS_CTS_TPC);
1075         rts_cts_rate = get(AR9170_MAC_REG_RTS_CTS_RATE);
1076
1077 #ifdef CONFIG_CARL9170FW_RADIO_FUNCTIONS
1078         /* 0x1c8960 write only */
1079         rx_BB = get(AR9170_PHY_REG_SWITCH_CHAIN_0);
1080 #endif /* CONFIG_CARL9170FW_RADIO_FUNCTIONS */
1081
1082         /* TX/RX must be stopped by now */
1083         val = get(AR9170_MAC_REG_POWER_STATE_CTRL);
1084
1085         val |= AR9170_MAC_POWER_STATE_CTRL_RESET;
1086
1087         /*
1088          * Manipulate CCA threshold to stop transmission
1089          *
1090          * set(AR9170_PHY_REG_CCA_THRESHOLD, 0x300);
1091          */
1092
1093         /*
1094          * check Rx state in 0(idle) 9(disable)
1095          *
1096          * chState = (get(AR9170_MAC_REG_MISC_684) >> 16) & 0xf;
1097          * while( (chState != 0) && (chState != 9)) {
1098          *      chState = (get(AR9170_MAC_REG_MISC_684) >> 16) & 0xf;
1099          * }
1100          */
1101
1102         set(AR9170_MAC_REG_POWER_STATE_CTRL, val);
1103
1104         delay(2);
1105
1106         /* Restore aggregation parameters */
1107         set(AR9170_MAC_REG_AMPDU_FACTOR, agg_wait_counter);
1108         set(AR9170_MAC_REG_AMPDU_DENSITY, agg_density);
1109
1110         set(AR9170_MAC_REG_BCN_ADDR, bcn_start_addr);
1111         set(AR9170_MAC_REG_CAM_MODE, cam_mode);
1112         set(AR9170_MAC_REG_CAM_ROLL_CALL_TBL_L, rctl);
1113         set(AR9170_MAC_REG_CAM_ROLL_CALL_TBL_H, rcth);
1114
1115         set(AR9170_MAC_REG_RTS_CTS_TPC, rts_cts_tpc);
1116         set(AR9170_MAC_REG_ACK_TPC, ack_power);
1117         set(AR9170_MAC_REG_RTS_CTS_RATE, rts_cts_rate);
1118
1119 #ifdef CONFIG_CARL9170FW_RADIO_FUNCTIONS
1120         set(AR9170_PHY_REG_SWITCH_CHAIN_2, rx_BB);
1121 #endif /* CONFIG_CARL9170FW_RADIO_FUNCTIONS */
1122
1123         /*
1124          * Manipulate CCA threshold to resume transmission
1125          *
1126          * set(AR9170_PHY_REG_CCA_THRESHOLD, 0x0);
1127          */
1128
1129         val = AR9170_DMA_TRIGGER_RXQ;
1130         /* Reinitialize all WLAN TX DMA queues. */
1131         for (i = AR9170_TXQ_SPECIAL; i >= AR9170_TXQ0; i--) {
1132                 struct dma_desc *iter;
1133
1134                 __for_each_desc_bits(iter, &fw.wlan.tx_queue[i], AR9170_OWN_BITS_SW);
1135
1136                 /* kill the stuck frame */
1137                 if (!is_terminator(&fw.wlan.tx_queue[i], iter) &&
1138                     fw.wlan.last_super_num[i] >= CARL9170FW_TX_MAC_RESET &&
1139                     fw.wlan.last_super[i] == DESC_PAYLOAD(iter)) {
1140                         struct carl9170_tx_superframe *super = get_super(iter);
1141
1142                         iter->status = AR9170_OWN_BITS_SW;
1143                         /*
1144                          * Mark the frame as failed.
1145                          * The BAFAIL flag allows the frame to sail through
1146                          * wlan_tx_status without much "unstuck" trouble.
1147                          */
1148                         iter->ctrl &= ~(AR9170_CTRL_FAIL);
1149                         iter->ctrl |= AR9170_CTRL_BAFAIL;
1150
1151                         super->s.cnt = CARL9170_TX_MAX_RATE_TRIES;
1152                         super->s.rix = CARL9170_TX_MAX_RETRY_RATES;
1153
1154                         fw.wlan.last_super_num[i] = 0;
1155                         fw.wlan.last_super[i] = NULL;
1156                         iter = iter->lastAddr->nextAddr;
1157                 }
1158
1159                 set_wlan_txq_dma_addr(i, (uint32_t) iter);
1160                 if (!is_terminator(&fw.wlan.tx_queue[i], iter))
1161                         val |= BIT(i);
1162
1163                 DBG("Q:%d l:%d h:%p t:%p cu:%p it:%p ct:%x st:%x\n", i, queue_len(&fw.wlan.tx_queue[i]),
1164                      fw.wlan.tx_queue[i].head, fw.wlan.tx_queue[i].terminator,
1165                      get_wlan_txq_addr(i), iter, iter->ctrl, iter->status);
1166         }
1167
1168         fw.wlan.soft_int |= AR9170_MAC_INT_RXC | AR9170_MAC_INT_TXC |
1169                             AR9170_MAC_INT_RETRY_FAIL;
1170
1171         set(AR9170_MAC_REG_DMA_RXQ_ADDR, (uint32_t) fw.wlan.rx_queue.head);
1172         wlan_trigger(val);
1173 }
1174 #else
1175 static void wlan_mac_reset(void)
1176 {
1177         /* The driver takes care of reinitializing the device */
1178         BUG("MAC RESET");
1179 }
1180 #endif /* CONFIG_CARL9170FW_FW_MAC_RESET */
1181
1182 void __cold wlan_timer(void)
1183 {
1184         unsigned int cached_mac_reset;
1185
1186         cached_mac_reset = fw.wlan.mac_reset;
1187
1188         /* TX Queue Hang check */
1189         wlan_check_hang();
1190
1191         /* RX Overrun check */
1192         wlan_check_rx_overrun();
1193
1194         if (unlikely(fw.wlan.mac_reset >= CARL9170_MAC_RESET_RESET)) {
1195                 wlan_mac_reset();
1196                 fw.wlan.mac_reset = CARL9170_MAC_RESET_OFF;
1197         } else {
1198                 if (fw.wlan.mac_reset && cached_mac_reset == fw.wlan.mac_reset)
1199                         fw.wlan.mac_reset--;
1200         }
1201 }