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         if (!!(desc->ctrl & AR9170_CTRL_FAIL)) {
 349                 txfail = !!(desc->ctrl & AR9170_CTRL_TXFAIL);
 350
 351                 /* reset retry indicator flags */
 352                 desc->ctrl &= ~(AR9170_CTRL_TXFAIL | AR9170_CTRL_BAFAIL);
 353
 354                 /*
 355                  * Note: wlan_tx_consume_retry will override the old
 356                  * phy [CCK,OFDM, HT, BW20/40, MCS...] and mac vectors
 357                  * [AMPDU,RTS/CTS,...] therefore be careful when they
 358                  * are used.
 359                  */
 360                 if (wlan_tx_consume_retry(super)) {
 361                         /*
 362                          * retry for simple and aggregated 802.11 frames.
 363                          *
 364                          * Note: We must not mess up the original frame
 365                          * order.
 366                          */
 367
 368                         if (!super->f.hdr.mac.ampdu) {
 369                                 /*
 370                                  * 802.11 - 7.1.3.1.5.
 371                                  * set "Retry Field" for consecutive attempts
 372                                  *
 373                                  * Note: For AMPDU see:
 374                                  * 802.11n 9.9.1.6 "Retransmit Procedures"
 375                                  */
 376                                 super->f.data.i3e.frame_control |=
 377                                         cpu_to_le16(IEEE80211_FCTL_RETRY);
 378                         }
 379
 380                         if (txfail) {
 381                                 /* Normal TX Failure */
 382
 383                                 /* demise descriptor ownership back to the hardware */
 384                                 dma_rearm(desc);
 385
 386                                 /*
 387                                  * And this will get the queue going again.
 388                                  * To understand why: you have to get the HW
 389                                  * specs... But sadly I never saw them.
 390                                  */
 391                                 wlan_txunstuck(qidx);
 392
 393                                 /* abort cycle - this is necessary due to HW design */
 394                                 return false;
 395                         } else {
 396                                 /* (HT-) BlockACK failure */
 397
 398                                 /*
 399                                  * Unlink the failed attempt and put it into
 400                                  * the retry queue. The caller routine must
 401                                  * be aware of this so the frames don't get lost.
 402                                  */
 403
 404 #ifndef CONFIG_CARL9170FW_DEBUG
 405                                 dma_unlink_head(queue);
 406 #else /* CONFIG_CARL9170FW_DEBUG */
 407                                 BUG_ON(dma_unlink_head(queue) != desc);
 408 #endif /* CONFIG_CARL9170FW_DEBUG */
 409                                 dma_put(&fw.wlan.tx_retry, desc);
 410                                 return true;
 411                         }
 412                 } else {
 413                         /* out of frame attempts - discard frame */
 414                         success = false;
 415                 }
 416         }
 417
 418 #ifndef CONFIG_CARL9170FW_DEBUG
 419         dma_unlink_head(queue);
 420 #else /* CONFIG_CARL9170FW_DEBUG */
 421         BUG_ON(dma_unlink_head(queue) != desc);
 422 #endif /* CONFIG_CARL9170FW_DEBUG */
 423         if (txfail) {
 424                 /*
 425                  * Issue the queue bump,
 426                  * We need to do this in case this was the frame's last
 427                  * possible retry attempt and it unfortunately: it failed.
 428                  */
 429
 430                 wlan_txunstuck(qidx);
 431         }
 432
 433         unhide_super(desc);
 434
 435         if (unlikely(super == fw.wlan.fw_desc_data)) {
 436                 fw.wlan.fw_desc = desc;
 437                 fw.wlan.fw_desc_available = 1;
 438
 439                 if (fw.wlan.fw_desc_callback)
 440                         fw.wlan.fw_desc_callback(super, success);
 441
 442                 return true;
 443         }
 444
 445 #ifdef CONFIG_CARL9170FW_CAB_QUEUE
 446         if (unlikely(super->s.cab))
 447                 fw.wlan.cab_queue_len[super->s.vif_id]--;
 448 #endif /* CONFIG_CARL9170FW_CAB_QUEUE */
 449
 450         wlan_tx_complete(super, success);
 451
 452         /* recycle freed descriptors */
 453         dma_reclaim(&fw.pta.down_queue, desc);
 454         down_trigger();
 455         return true;
 456 }
 457
 458 static void handle_tx_completion(void)
 459 {
 460         struct dma_desc *desc;
 461         int i;
 462
 463         for (i = AR9170_TXQ_SPECIAL; i >= AR9170_TXQ0; i--) {
 464                 __while_desc_bits(desc, &fw.wlan.tx_queue[i], AR9170_OWN_BITS_SW) {
 465                         if (!wlan_tx_status(&fw.wlan.tx_queue[i], desc)) {
 466                                 /* termination requested. */
 467                                 break;
 468                         }
 469                 }
 470
 471                 wlan_tx_ampdu_reset(i);
 472
 473                 for_each_desc(desc, &fw.wlan.tx_retry)
 474                         __wlan_tx(desc);
 475
 476                 wlan_tx_ampdu_end(i);
 477                 if (!queue_empty(&fw.wlan.tx_queue[i]))
 478                         wlan_trigger(BIT(i));
 479         }
 480 }
 481
 482 void __hot wlan_tx(struct dma_desc *desc)
 483 {
 484         struct carl9170_tx_superframe *super = DESC_PAYLOAD(desc);
 485
 486         /* initialize rate control struct */
 487         super->s.rix = 0;
 488         super->s.cnt = 1;
 489         hide_super(desc);
 490
 491 #ifdef CONFIG_CARL9170FW_CAB_QUEUE
 492         if (unlikely(super->s.cab)) {
 493                 fw.wlan.cab_queue_len[super->s.vif_id]++;
 494                 dma_put(&fw.wlan.cab_queue[super->s.vif_id], desc);
 495                 return;
 496         }
 497 #endif /* CONFIG_CARL9170FW_CAB_QUEUE */
 498
 499         _wlan_tx(desc);
 500         __wlan_tx(desc);
 501         wlan_trigger(BIT(super->s.queue));
 502 }
 503
 504 void wlan_tx_fw(struct carl9170_tx_superdesc *super, fw_desc_callback_t cb)
 505 {
 506         if (!fw.wlan.fw_desc_available)
 507                 return;
 508
 509         fw.wlan.fw_desc_available = 0;
 510
 511         /* Format BlockAck */
 512         fw.wlan.fw_desc->ctrl = AR9170_CTRL_FS_BIT | AR9170_CTRL_LS_BIT;
 513         fw.wlan.fw_desc->status = AR9170_OWN_BITS_SW;
 514
 515         fw.wlan.fw_desc->totalLen = fw.wlan.fw_desc->dataSize = super->len;
 516         fw.wlan.fw_desc_data = fw.wlan.fw_desc->dataAddr = super;
 517         fw.wlan.fw_desc->nextAddr = fw.wlan.fw_desc->lastAddr =
 518                 fw.wlan.fw_desc;
 519         fw.wlan.fw_desc_callback = cb;
 520         wlan_tx(fw.wlan.fw_desc);
 521 }
 522
 523 static void wlan_send_buffered_ba(void)
 524 {
 525         struct carl9170_tx_ba_superframe *baf = &dma_mem.reserved.ba.ba;
 526         struct ieee80211_ba *ba = (struct ieee80211_ba *) &baf->f.ba;
 527         struct carl9170_bar_ctx *ctx;
 528
 529         if (likely(!fw.wlan.queued_ba))
 530                 return;
 531
 532         /* there's no point to continue when the ba_desc is not available. */
 533         if (!fw.wlan.fw_desc_available)
 534                 return;
 535
 536         ctx = &fw.wlan.ba_cache[fw.wlan.ba_head_idx];
 537         fw.wlan.ba_head_idx++;
 538         fw.wlan.ba_head_idx %= CONFIG_CARL9170FW_BACK_REQS_NUM;
 539         fw.wlan.queued_ba--;
 540
 541         baf->s.len = sizeof(struct carl9170_tx_superdesc) +
 542                      sizeof(struct ar9170_tx_hwdesc) +
 543                      sizeof(struct ieee80211_ba);
 544         baf->s.ri[0].tries = 1;
 545         baf->s.cookie = 0;
 546         baf->s.queue = AR9170_TXQ_VO;
 547         baf->f.hdr.length = sizeof(struct ieee80211_ba) + FCS_LEN;
 548
 549         baf->f.hdr.mac.no_ack = 1;
 550
 551         baf->f.hdr.phy.modulation = 1; /* OFDM */
 552         baf->f.hdr.phy.tx_power = 34; /* 17 dBm */
 553         baf->f.hdr.phy.chains = 1;
 554         baf->f.hdr.phy.mcs = AR9170_TXRX_PHY_RATE_OFDM_6M;
 555
 556         /* format outgoing BA */
 557         ba->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_NULLFUNC);
 558         ba->duration = cpu_to_le16(0);
 559         memcpy(ba->ta, ctx->ta, 6);
 560         memcpy(ba->ra, ctx->ra, 6);
 561
 562         /*
 563          * Unfortunately, we cannot look into the hardware's scoreboard.
 564          * Therefore we have to proceed as described in 802.11n 9.10.7.5
 565          * and send a null BlockAck.
 566          */
 567         memset(ba->bitmap, 0x0, sizeof(ba->bitmap));
 568
 569         /*
 570          * NB:
 571          * not entirely sure if this is 100% correct?!
 572          */
 573         ba->control = ctx->control | cpu_to_le16(1);
 574         ba->start_seq_num = ctx->start_seq_num;
 575         wlan_tx_fw(&baf->s, NULL);
 576 }
 577
 578 static struct carl9170_bar_ctx *wlan_get_bar_cache_buffer(void)
 579 {
 580         struct carl9170_bar_ctx *tmp;
 581
 582         tmp = &fw.wlan.ba_cache[fw.wlan.ba_tail_idx];
 583         fw.wlan.ba_tail_idx++;
 584         fw.wlan.ba_tail_idx %= CONFIG_CARL9170FW_BACK_REQS_NUM;
 585         if (fw.wlan.queued_ba < CONFIG_CARL9170FW_BACK_REQS_NUM)
 586                 fw.wlan.queued_ba++;
 587
 588         return tmp;
 589 }
 590
 591 static void handle_bar(struct dma_desc *desc __unused, struct ieee80211_hdr *hdr,
 592                        unsigned int len, unsigned int mac_err)
 593 {
 594         struct ieee80211_bar *bar;
 595         struct carl9170_bar_ctx *ctx;
 596
 597         if (unlikely(mac_err)) {
 598                 /*
 599                  * This check does a number of things:
 600                  * 1. checks if the frame is in good nick
 601                  * 2. checks if the RA (MAC) matches
 602                  */
 603                 return ;
 604         }
 605
 606         if (unlikely(len < (sizeof(struct ieee80211_bar) + FCS_LEN))) {
 607                 /*
 608                  * Sneaky, corrupted BARs... but not with us!
 609                  */
 610
 611                 return ;
 612         }
 613
 614         bar = (void *) hdr;
 615
 616         if ((bar->control & cpu_to_le16(IEEE80211_BAR_CTRL_MULTI_TID)) ||
 617             !(bar->control & cpu_to_le16(IEEE80211_BAR_CTRL_CBMTID_COMPRESSED_BA))) {
 618                 /* not implemented yet */
 619
 620                 return ;
 621         }
 622
 623         ctx = wlan_get_bar_cache_buffer();
 624
 625         /* Brilliant! The BAR provides all necessary MACs! */
 626         memcpy(ctx->ra, bar->ta, 6);
 627         memcpy(ctx->ta, bar->ra, 6);
 628
 629         /*
 630          * NB:
 631          * not entirely sure if this is 100% correct to force the
 632          * imm ack bit or not...
 633          */
 634         ctx->control = bar->control | cpu_to_le16(1);
 635         ctx->start_seq_num = bar->start_seq_num;
 636 }
 637
 638 static void wlan_check_rx_overrun(void)
 639 {
 640         uint32_t overruns, total;
 641
 642         fw.tally.rx_total += total = get(AR9170_MAC_REG_RX_TOTAL);
 643         fw.tally.rx_overrun += overruns = get(AR9170_MAC_REG_RX_OVERRUN);
 644         if (unlikely(overruns)) {
 645                 if (overruns == total) {
 646                         DBG("RX Overrun");
 647                         fw.wlan.mac_reset++;
 648                 }
 649
 650                 wlan_trigger(AR9170_DMA_TRIGGER_RXQ);
 651         }
 652 }
 653
 654 static unsigned int wlan_rx_filter(struct dma_desc *desc)
 655 {
 656         struct ieee80211_hdr *hdr;
 657         unsigned int data_len;
 658         unsigned int rx_filter;
 659         unsigned int mac_err;
 660
 661         data_len = ar9170_get_rx_mpdu_len(desc);
 662         mac_err = ar9170_get_rx_macstatus_error(desc);
 663
 664 #define AR9170_RX_ERROR_BAD (AR9170_RX_ERROR_FCS | AR9170_RX_ERROR_PLCP)
 665
 666         if (unlikely(data_len < (4 + 6 + FCS_LEN) ||
 667             desc->totalLen > CONFIG_CARL9170FW_RX_FRAME_LEN) ||
 668             mac_err & AR9170_RX_ERROR_BAD) {
 669                 /*
 670                  * This frame is too damaged to do anything
 671                  * useful with it.
 672                  */
 673
 674                 return CARL9170_RX_FILTER_BAD;
 675         }
 676
 677         rx_filter = 0;
 678         if (mac_err & AR9170_RX_ERROR_WRONG_RA)
 679                 rx_filter |= CARL9170_RX_FILTER_OTHER_RA;
 680
 681         if (mac_err & AR9170_RX_ERROR_DECRYPT)
 682                 rx_filter |= CARL9170_RX_FILTER_DECRY_FAIL;
 683
 684         hdr = ar9170_get_rx_i3e(desc);
 685         if (likely(ieee80211_is_data(hdr->frame_control))) {
 686                 rx_filter |= CARL9170_RX_FILTER_DATA;
 687         } else if (ieee80211_is_ctl(hdr->frame_control)) {
 688                 switch (le16_to_cpu(hdr->frame_control) & IEEE80211_FCTL_STYPE) {
 689                 case IEEE80211_STYPE_BACK_REQ:
 690                         handle_bar(desc, hdr, data_len, mac_err);
 691                         /* fallthrough */
 692                         rx_filter |= CARL9170_RX_FILTER_CTL_BACKR;
 693                         break;
 694                 case IEEE80211_STYPE_PSPOLL:
 695                         rx_filter |= CARL9170_RX_FILTER_CTL_PSPOLL;
 696                         break;
 697                 default:
 698                         rx_filter |= CARL9170_RX_FILTER_CTL_OTHER;
 699                         break;
 700                 }
 701         } else {
 702                 /* ieee80211_is_mgmt */
 703                 rx_filter |= CARL9170_RX_FILTER_MGMT;
 704         }
 705
 706         if (unlikely(fw.suspend_mode == CARL9170_HOST_SUSPENDED)) {
 707                 wol_rx(rx_filter, hdr, min(data_len,
 708                         (unsigned int)AR9170_BLOCK_SIZE));
 709         }
 710
 711 #undef AR9170_RX_ERROR_BAD
 712
 713         return rx_filter;
 714 }
 715
 716 static void handle_rx(void)
 717 {
 718         struct dma_desc *desc;
 719
 720         for_each_desc_not_bits(desc, &fw.wlan.rx_queue, AR9170_OWN_BITS_HW) {
 721                 if (!(wlan_rx_filter(desc) & fw.wlan.rx_filter)) {
 722                         dma_put(&fw.pta.up_queue, desc);
 723                         up_trigger();
 724                 } else {
 725                         dma_reclaim(&fw.wlan.rx_queue, desc);
 726                         wlan_trigger(AR9170_DMA_TRIGGER_RXQ);
 727                 }
 728         }
 729 }
 730
 731 #ifdef CONFIG_CARL9170FW_CAB_QUEUE
 732 void wlan_cab_flush_queue(const unsigned int vif)
 733 {
 734         struct dma_queue *cab_queue = &fw.wlan.cab_queue[vif];
 735         struct dma_desc *desc;
 736
 737         /* move queued frames into the main tx queues */
 738         for_each_desc(desc, cab_queue) {
 739                 struct carl9170_tx_superframe *super = get_super(desc);
 740                 if (!queue_empty(cab_queue)) {
 741                         /*
 742                          * Set MOREDATA flag for all,
 743                          * but the last queued frame.
 744                          * see: 802.11-2007 11.2.1.5 f)
 745                          *
 746                          * This is actually the reason to why
 747                          * we need to prevent the reentry.
 748                          */
 749
 750                         super->f.data.i3e.frame_control |=
 751                                 cpu_to_le16(IEEE80211_FCTL_MOREDATA);
 752                 } else {
 753                         super->f.data.i3e.frame_control &=
 754                                 cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
 755                 }
 756
 757                 /* ready to roll! */
 758                 _wlan_tx(desc);
 759                 __wlan_tx(desc);
 760                 wlan_trigger(BIT(super->s.queue));
 761         }
 762 }
 763
 764 static uint8_t *beacon_find_ie(uint8_t ie, void *addr,
 765                                const unsigned int len)
 766 {
 767         struct ieee80211_mgmt *mgmt = addr;
 768         uint8_t *pos, *end;
 769
 770         pos = mgmt->u.beacon.variable;
 771         end = (uint8_t *) ((unsigned long)mgmt + (len - FCS_LEN));
 772         while (pos < end) {
 773                 if (pos + 2 + pos[1] > end)
 774                         return NULL;
 775
 776                 if (pos[0] == ie)
 777                         return pos;
 778
 779                 pos += pos[1] + 2;
 780         }
 781
 782         return NULL;
 783 }
 784
 785 void wlan_modify_beacon(const unsigned int vif,
 786         const unsigned int addr, const unsigned int len)
 787 {
 788         uint8_t *_ie;
 789         struct ieee80211_tim_ie *ie;
 790
 791         _ie = beacon_find_ie(WLAN_EID_TIM, (void *)addr, len);
 792         if (likely(_ie)) {
 793                 ie = (struct ieee80211_tim_ie *) &_ie[2];
 794
 795                 if (!queue_empty(&fw.wlan.cab_queue[vif]) && (ie->dtim_count == 0)) {
 796                         /* schedule DTIM transfer */
 797                         fw.wlan.cab_flush_trigger[vif] = CARL9170_CAB_TRIGGER_ARMED;
 798                 } else if ((fw.wlan.cab_queue_len[vif] == 0) && (fw.wlan.cab_flush_trigger[vif])) {
 799                         /* undo all chances to the beacon structure */
 800                         ie->bitmap_ctrl &= ~0x1;
 801                         fw.wlan.cab_flush_trigger[vif] = CARL9170_CAB_TRIGGER_EMPTY;
 802                 }
 803
 804                 /* Triggered by CARL9170_CAB_TRIGGER_ARMED || CARL9170_CAB_TRIGGER_DEFER */
 805                 if (fw.wlan.cab_flush_trigger[vif]) {
 806                         /* Set the almighty Multicast Traffic Indication Bit. */
 807                         ie->bitmap_ctrl |= 0x1;
 808                 }
 809         }
 810
 811         /*
 812          * Ideally, the sequence number should be assigned by the TX arbiter
 813          * hardware. But AFAIK that's not possible, so we have to go for the
 814          * next best thing and write it into the beacon fifo during the open
 815          * beacon update window.
 816          */
 817
 818         wlan_assign_seq((struct ieee80211_hdr *)addr, vif);
 819 }
 820
 821 static void wlan_send_buffered_cab(void)
 822 {
 823         unsigned int i;
 824
 825         for (i = 0; i < CARL9170_INTF_NUM; i++) {
 826                 if (unlikely(fw.wlan.cab_flush_trigger[i] == CARL9170_CAB_TRIGGER_ARMED)) {
 827                         /*
 828                          * This is hardcoded into carl9170usb driver.
 829                          *
 830                          * The driver must set the PRETBTT event to beacon_interval -
 831                          * CARL9170_PRETBTT_KUS (usually 6) Kus.
 832                          *
 833                          * But still, we can only do so much about 802.11-2007 9.3.2.1 &
 834                          * 11.2.1.6. Let's hope the current solution is adequate enough.
 835                          */
 836
 837                         if (is_after_msecs(fw.wlan.cab_flush_time, (CARL9170_TBTT_DELTA))) {
 838                                 wlan_cab_flush_queue(i);
 839
 840                                 /*
 841                                  * This prevents the code from sending new BC/MC frames
 842                                  * which were queued after the previous buffered traffic
 843                                  * has been sent out... They will have to wait until the
 844                                  * next DTIM beacon comes along.
 845                                  */
 846                                 fw.wlan.cab_flush_trigger[i] = CARL9170_CAB_TRIGGER_DEFER;
 847                         }
 848                 }
 849
 850         }
 851 }
 852 #endif /* CONFIG_CARL9170FW_CAB_QUEUE */
 853
 854 static void handle_beacon_config(void)
 855 {
 856         uint32_t bcn_count;
 857
 858         bcn_count = get(AR9170_MAC_REG_BCN_COUNT);
 859         send_cmd_to_host(4, CARL9170_RSP_BEACON_CONFIG, 0x00,
 860                          (uint8_t *) &bcn_count);
 861 }
 862
 863 static void handle_pretbtt(void)
 864 {
 865 #ifdef CONFIG_CARL9170FW_CAB_QUEUE
 866         fw.wlan.cab_flush_time = get_clock_counter();
 867 #endif /* CONFIG_CARL9170FW_CAB_QUEUE */
 868
 869 #ifdef CONFIG_CARL9170FW_RADIO_FUNCTIONS
 870         rf_psm();
 871
 872         send_cmd_to_host(4, CARL9170_RSP_PRETBTT, 0x00,
 873                          (uint8_t *) &fw.phy.psm.state);
 874 #endif /* CONFIG_CARL9170FW_RADIO_FUNCTIONS */
 875 }
 876
 877 static void handle_atim(void)
 878 {
 879         send_cmd_to_host(0, CARL9170_RSP_ATIM, 0x00, NULL);
 880 }
 881
 882 #ifdef CONFIG_CARL9170FW_DEBUG
 883 static void handle_qos(void)
 884 {
 885         /*
 886          * What is the QoS Bit used for?
 887          * Is it only an indicator for TXOP & Burst, or
 888          * should we do something here?
 889          */
 890 }
 891
 892 static void handle_radar(void)
 893 {
 894         send_cmd_to_host(0, CARL9170_RSP_RADAR, 0x00, NULL);
 895 }
 896 #endif /* CONFIG_CARL9170FW_DEBUG */
 897
 898 static void wlan_janitor(void)
 899 {
 900 #ifdef CONFIG_CARL9170FW_CAB_QUEUE
 901         wlan_send_buffered_cab();
 902 #endif /* CONFIG_CARL9170FW_CAB_QUEUE */
 903
 904         wlan_send_buffered_tx_status();
 905
 906         wlan_send_buffered_ba();
 907
 908         wol_janitor();
 909 }
 910
 911 void handle_wlan(void)
 912 {
 913         uint32_t intr;
 914
 915         intr = get(AR9170_MAC_REG_INT_CTRL);
 916         /* ACK Interrupt */
 917         set(AR9170_MAC_REG_INT_CTRL, intr);
 918
 919 #define HANDLER(intr, flag, func)                       \
 920         do {                                            \
 921                 if ((intr & flag) != 0) {               \
 922                         func();                         \
 923                 }                                       \
 924         } while (0)
 925
 926         intr |= fw.wlan.soft_int;
 927         fw.wlan.soft_int = 0;
 928
 929         HANDLER(intr, AR9170_MAC_INT_PRETBTT, handle_pretbtt);
 930
 931         HANDLER(intr, AR9170_MAC_INT_ATIM, handle_atim);
 932
 933         HANDLER(intr, AR9170_MAC_INT_RXC, handle_rx);
 934
 935         HANDLER(intr, (AR9170_MAC_INT_TXC | AR9170_MAC_INT_RETRY_FAIL),
 936                 handle_tx_completion);
 937
 938 #ifdef CONFIG_CARL9170FW_DEBUG
 939         HANDLER(intr, AR9170_MAC_INT_QOS, handle_qos);
 940
 941         HANDLER(intr, AR9170_MAC_INT_RADAR, handle_radar);
 942 #endif /* CONFIG_CARL9170FW_DEBUG */
 943
 944         HANDLER(intr, AR9170_MAC_INT_CFG_BCN, handle_beacon_config);
 945
 946         if (unlikely(intr))
 947                 DBG("Unhandled Interrupt %x\n", (unsigned int) intr);
 948
 949         wlan_janitor();
 950
 951 #undef HANDLER
 952 }
 953
 954 enum {
 955         CARL9170FW_TX_MAC_BUMP = 4,
 956         CARL9170FW_TX_MAC_DEBUG = 6,
 957         CARL9170FW_TX_MAC_RESET = 7,
 958 };
 959
 960 static void wlan_check_hang(void)
 961 {
 962         struct dma_desc *desc;
 963         int i;
 964
 965         for (i = AR9170_TXQ_SPECIAL; i >= AR9170_TXQ0; i--) {
 966                 if (queue_empty(&fw.wlan.tx_queue[i])) {
 967                         /* Nothing to do here... move along */
 968                         continue;
 969                 }
 970
 971                 /* fetch the current DMA queue position */
 972                 desc = (struct dma_desc *)get_wlan_txq_addr(i);
 973
 974                 /* Stuck frame detection */
 975                 if (unlikely(DESC_PAYLOAD(desc) == fw.wlan.last_super[i])) {
 976                         fw.wlan.last_super_num[i]++;
 977
 978                         if (unlikely(fw.wlan.last_super_num[i] >= CARL9170FW_TX_MAC_RESET)) {
 979                                 /*
 980                                  * schedule MAC reset (aka OFF/ON => dead)
 981                                  *
 982                                  * This will almost certainly kill
 983                                  * the device for good, but it's the
 984                                  * recommended thing to do...
 985                                  */
 986
 987                                 fw.wlan.mac_reset++;
 988                         }
 989
 990 #ifdef CONFIG_CARL9170FW_DEBUG
 991                         if (unlikely(fw.wlan.last_super_num[i] >= CARL9170FW_TX_MAC_DEBUG)) {
 992                                 /*
 993                                  * Sigh, the queue is almost certainly
 994                                  * dead. Dump the queue content to the
 995                                  * user, maybe we find out why it got
 996                                  * so stuck.
 997                                  */
 998
 999                                 wlan_dump_queue(i);
1000                         }
1001 #endif /* CONFIG_CARL9170FW_DEBUG */
1002
1003 #ifdef CONFIG_CARL9170FW_DMA_QUEUE_BUMP
1004                         if (unlikely(fw.wlan.last_super_num[i] >= CARL9170FW_TX_MAC_BUMP)) {
1005                                 /*
1006                                  * Hrrm, bump the queue a bit.
1007                                  * maybe this will get it going again.
1008                                  */
1009
1010                                 wlan_dma_bump(i);
1011                                 wlan_trigger(BIT(i));
1012                         }
1013 #endif /* CONFIG_CARL9170FW_DMA_QUEUE_BUMP */
1014                 } else {
1015                         /* Nothing stuck */
1016                         fw.wlan.last_super[i] = DESC_PAYLOAD(desc);
1017                         fw.wlan.last_super_num[i] = 0;
1018                 }
1019         }
1020 }
1021
1022 #ifdef CONFIG_CARL9170FW_FW_MAC_RESET
1023 /*
1024  * NB: Resetting the MAC is a two-edged sword.
1025  * On most occasions, it does what it is supposed to do.
1026  * But there is a chance that this will make it
1027  * even worse and the radio dies silently.
1028  */
1029 static void wlan_mac_reset(void)
1030 {
1031         uint32_t val;
1032         uint32_t agg_wait_counter;
1033         uint32_t agg_density;
1034         uint32_t bcn_start_addr;
1035         uint32_t rctl, rcth;
1036         uint32_t cam_mode;
1037         uint32_t ack_power;
1038         uint32_t rts_cts_tpc;
1039         uint32_t rts_cts_rate;
1040         int i;
1041
1042 #ifdef CONFIG_CARL9170FW_RADIO_FUNCTIONS
1043         uint32_t rx_BB;
1044 #endif /* CONFIG_CARL9170FW_RADIO_FUNCTIONS */
1045
1046 #ifdef CONFIG_CARL9170FW_NOISY_MAC_RESET
1047         INFO("MAC RESET");
1048 #endif /* CONFIG_CARL9170FW_NOISY_MAC_RESET */
1049
1050         /* Save aggregation parameters */
1051         agg_wait_counter = get(AR9170_MAC_REG_AMPDU_FACTOR);
1052         agg_density = get(AR9170_MAC_REG_AMPDU_DENSITY);
1053
1054         bcn_start_addr = get(AR9170_MAC_REG_BCN_ADDR);
1055
1056         cam_mode = get(AR9170_MAC_REG_CAM_MODE);
1057         rctl = get(AR9170_MAC_REG_CAM_ROLL_CALL_TBL_L);
1058         rcth = get(AR9170_MAC_REG_CAM_ROLL_CALL_TBL_H);
1059
1060         ack_power = get(AR9170_MAC_REG_ACK_TPC);
1061         rts_cts_tpc = get(AR9170_MAC_REG_RTS_CTS_TPC);
1062         rts_cts_rate = get(AR9170_MAC_REG_RTS_CTS_RATE);
1063
1064 #ifdef CONFIG_CARL9170FW_RADIO_FUNCTIONS
1065         /* 0x1c8960 write only */
1066         rx_BB = get(AR9170_PHY_REG_SWITCH_CHAIN_0);
1067 #endif /* CONFIG_CARL9170FW_RADIO_FUNCTIONS */
1068
1069         /* TX/RX must be stopped by now */
1070         val = get(AR9170_MAC_REG_POWER_STATE_CTRL);
1071
1072         val |= AR9170_MAC_POWER_STATE_CTRL_RESET;
1073
1074         /*
1075          * Manipulate CCA threshold to stop transmission
1076          *
1077          * set(AR9170_PHY_REG_CCA_THRESHOLD, 0x300);
1078          */
1079
1080         /*
1081          * check Rx state in 0(idle) 9(disable)
1082          *
1083          * chState = (get(AR9170_MAC_REG_MISC_684) >> 16) & 0xf;
1084          * while( (chState != 0) && (chState != 9)) {
1085          *      chState = (get(AR9170_MAC_REG_MISC_684) >> 16) & 0xf;
1086          * }
1087          */
1088
1089         set(AR9170_MAC_REG_POWER_STATE_CTRL, val);
1090
1091         delay(2);
1092
1093         /* Restore aggregation parameters */
1094         set(AR9170_MAC_REG_AMPDU_FACTOR, agg_wait_counter);
1095         set(AR9170_MAC_REG_AMPDU_DENSITY, agg_density);
1096
1097         set(AR9170_MAC_REG_BCN_ADDR, bcn_start_addr);
1098         set(AR9170_MAC_REG_CAM_MODE, cam_mode);
1099         set(AR9170_MAC_REG_CAM_ROLL_CALL_TBL_L, rctl);
1100         set(AR9170_MAC_REG_CAM_ROLL_CALL_TBL_H, rcth);
1101
1102         set(AR9170_MAC_REG_RTS_CTS_TPC, rts_cts_tpc);
1103         set(AR9170_MAC_REG_ACK_TPC, ack_power);
1104         set(AR9170_MAC_REG_RTS_CTS_RATE, rts_cts_rate);
1105
1106 #ifdef CONFIG_CARL9170FW_RADIO_FUNCTIONS
1107         set(AR9170_PHY_REG_SWITCH_CHAIN_2, rx_BB);
1108 #endif /* CONFIG_CARL9170FW_RADIO_FUNCTIONS */
1109
1110         /*
1111          * Manipulate CCA threshold to resume transmission
1112          *
1113          * set(AR9170_PHY_REG_CCA_THRESHOLD, 0x0);
1114          */
1115
1116         val = AR9170_DMA_TRIGGER_RXQ;
1117         /* Reinitialize all WLAN TX DMA queues. */
1118         for (i = AR9170_TXQ_SPECIAL; i >= AR9170_TXQ0; i--) {
1119                 struct dma_desc *iter;
1120
1121                 __for_each_desc_bits(iter, &fw.wlan.tx_queue[i], AR9170_OWN_BITS_SW);
1122
1123                 /* kill the stuck frame */
1124                 if (!is_terminator(&fw.wlan.tx_queue[i], iter) &&
1125                     fw.wlan.last_super_num[i] >= CARL9170FW_TX_MAC_RESET &&
1126                     fw.wlan.last_super[i] == DESC_PAYLOAD(iter)) {
1127                         struct carl9170_tx_superframe *super = get_super(iter);
1128
1129                         iter->status = AR9170_OWN_BITS_SW;
1130                         /*
1131                          * Mark the frame as failed.
1132                          * The BAFAIL flag allows the frame to sail through
1133                          * wlan_tx_status without much "unstuck" trouble.
1134                          */
1135                         iter->ctrl &= ~(AR9170_CTRL_FAIL);
1136                         iter->ctrl |= AR9170_CTRL_BAFAIL;
1137
1138                         super->s.cnt = CARL9170_TX_MAX_RATE_TRIES;
1139                         super->s.rix = CARL9170_TX_MAX_RETRY_RATES;
1140
1141                         fw.wlan.last_super_num[i] = 0;
1142                         fw.wlan.last_super[i] = NULL;
1143                         iter = iter->lastAddr->nextAddr;
1144                 }
1145
1146                 set_wlan_txq_dma_addr(i, (uint32_t) iter);
1147                 if (!is_terminator(&fw.wlan.tx_queue[i], iter))
1148                         val |= BIT(i);
1149
1150                 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]),
1151                      fw.wlan.tx_queue[i].head, fw.wlan.tx_queue[i].terminator,
1152                      get_wlan_txq_addr(i), iter, iter->ctrl, iter->status);
1153         }
1154
1155         fw.wlan.soft_int |= AR9170_MAC_INT_RXC | AR9170_MAC_INT_TXC |
1156                             AR9170_MAC_INT_RETRY_FAIL;
1157
1158         set(AR9170_MAC_REG_DMA_RXQ_ADDR, (uint32_t) fw.wlan.rx_queue.head);
1159         wlan_trigger(val);
1160 }
1161 #else
1162 static void wlan_mac_reset(void)
1163 {
1164         /* The driver takes care of reinitializing the device */
1165         BUG("MAC RESET");
1166 }
1167 #endif /* CONFIG_CARL9170FW_FW_MAC_RESET */
1168
1169 void __cold wlan_timer(void)
1170 {
1171         unsigned int cached_mac_reset;
1172
1173         cached_mac_reset = fw.wlan.mac_reset;
1174
1175         /* TX Queue Hang check */
1176         wlan_check_hang();
1177
1178         /* RX Overrun check */
1179         wlan_check_rx_overrun();
1180
1181         if (unlikely(fw.wlan.mac_reset >= CARL9170_MAC_RESET_RESET)) {
1182                 wlan_mac_reset();
1183                 fw.wlan.mac_reset = CARL9170_MAC_RESET_OFF;
1184         } else {
1185                 if (fw.wlan.mac_reset && cached_mac_reset == fw.wlan.mac_reset)
1186                         fw.wlan.mac_reset--;
1187         }
1188 }