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 (!(hdr->seq_ctrl & cpu_to_le16(IEEE80211_SCTL_FRAG)))
 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                 if (wlan_tx_consume_retry(super)) {
 355                         /*
 356                          * retry for simple and aggregated 802.11 frames.
 357                          *
 358                          * Note: We must not mess up the original frame
 359                          * order.
 360                          */
 361
 362                         if (!super->f.hdr.mac.ampdu) {
 363                                 /*
 364                                  * 802.11 - 7.1.3.1.5.
 365                                  * set "Retry Field" for consecutive attempts
 366                                  *
 367                                  * Note: For AMPDU see:
 368                                  * 802.11n 9.9.1.6 "Retransmit Procedures"
 369                                  */
 370                                 super->f.data.i3e.frame_control |=
 371                                         cpu_to_le16(IEEE80211_FCTL_RETRY);
 372                         }
 373
 374                         if (txfail) {
 375                                 /* Normal TX Failure */
 376
 377                                 /* demise descriptor ownership back to the hardware */
 378                                 dma_rearm(desc);
 379
 380                                 /*
 381                                  * And this will get the queue going again.
 382                                  * To understand why: you have to get the HW
 383                                  * specs... But sadly I never saw them.
 384                                  */
 385                                 wlan_txunstuck(qidx);
 386
 387                                 /* abort cycle - this is necessary due to HW design */
 388                                 return false;
 389                         } else {
 390                                 /* (HT-) BlockACK failure */
 391
 392                                 /*
 393                                  * Unlink the failed attempt and put it into
 394                                  * the retry queue. The caller routine must
 395                                  * be aware of this so the frames don't get lost.
 396                                  */
 397
 398 #ifndef CONFIG_CARL9170FW_DEBUG
 399                                 dma_unlink_head(queue);
 400 #else /* CONFIG_CARL9170FW_DEBUG */
 401                                 BUG_ON(dma_unlink_head(queue) != desc);
 402 #endif /* CONFIG_CARL9170FW_DEBUG */
 403                                 dma_put(&fw.wlan.tx_retry, desc);
 404                                 return true;
 405                         }
 406                 } else {
 407                         /* out of frame attempts - discard frame */
 408                         success = false;
 409                 }
 410         }
 411
 412 #ifndef CONFIG_CARL9170FW_DEBUG
 413         dma_unlink_head(queue);
 414 #else /* CONFIG_CARL9170FW_DEBUG */
 415         BUG_ON(dma_unlink_head(queue) != desc);
 416 #endif /* CONFIG_CARL9170FW_DEBUG */
 417         if (txfail) {
 418                 /*
 419                  * Issue the queue bump,
 420                  * We need to do this in case this was the frame's last
 421                  * possible retry attempt and it unfortunately: it failed.
 422                  */
 423
 424                 wlan_txunstuck(qidx);
 425         }
 426
 427         unhide_super(desc);
 428
 429         if (unlikely(super == fw.wlan.fw_desc_data)) {
 430                 fw.wlan.fw_desc = desc;
 431                 fw.wlan.fw_desc_available = 1;
 432
 433                 if (fw.wlan.fw_desc_callback)
 434                         fw.wlan.fw_desc_callback(super, success);
 435
 436                 return true;
 437         }
 438
 439 #ifdef CONFIG_CARL9170FW_CAB_QUEUE
 440         if (unlikely(super->s.cab))
 441                 fw.wlan.cab_queue_len[super->s.vif_id]--;
 442 #endif /* CONFIG_CARL9170FW_CAB_QUEUE */
 443
 444         wlan_tx_complete(super, success);
 445
 446         /* recycle freed descriptors */
 447         dma_reclaim(&fw.pta.down_queue, desc);
 448         down_trigger();
 449         return true;
 450 }
 451
 452 static void handle_tx_completion(void)
 453 {
 454         struct dma_desc *desc;
 455         int i;
 456
 457         for (i = AR9170_TXQ_SPECIAL; i >= AR9170_TXQ0; i--) {
 458                 __while_desc_bits(desc, &fw.wlan.tx_queue[i], AR9170_OWN_BITS_SW) {
 459                         if (!wlan_tx_status(&fw.wlan.tx_queue[i], desc)) {
 460                                 /* termination requested. */
 461                                 break;
 462                         }
 463                 }
 464
 465                 wlan_tx_ampdu_reset(i);
 466
 467                 for_each_desc(desc, &fw.wlan.tx_retry)
 468                         __wlan_tx(desc);
 469
 470                 wlan_tx_ampdu_end(i);
 471                 if (!queue_empty(&fw.wlan.tx_queue[i]))
 472                         wlan_trigger(BIT(i));
 473         }
 474 }
 475
 476 void __hot wlan_tx(struct dma_desc *desc)
 477 {
 478         struct carl9170_tx_superframe *super = DESC_PAYLOAD(desc);
 479
 480         /* initialize rate control struct */
 481         super->s.rix = 0;
 482         super->s.cnt = 1;
 483         hide_super(desc);
 484
 485 #ifdef CONFIG_CARL9170FW_CAB_QUEUE
 486         if (unlikely(super->s.cab)) {
 487                 fw.wlan.cab_queue_len[super->s.vif_id]++;
 488                 dma_put(&fw.wlan.cab_queue[super->s.vif_id], desc);
 489                 return;
 490         }
 491 #endif /* CONFIG_CARL9170FW_CAB_QUEUE */
 492
 493         _wlan_tx(desc);
 494         __wlan_tx(desc);
 495         wlan_trigger(BIT(super->s.queue));
 496 }
 497
 498 void wlan_tx_fw(struct carl9170_tx_superdesc *super, fw_desc_callback_t cb)
 499 {
 500         if (!fw.wlan.fw_desc_available)
 501                 return;
 502
 503         fw.wlan.fw_desc_available = 0;
 504
 505         /* Format BlockAck */
 506         fw.wlan.fw_desc->ctrl = AR9170_CTRL_FS_BIT | AR9170_CTRL_LS_BIT;
 507         fw.wlan.fw_desc->status = AR9170_OWN_BITS_SW;
 508
 509         fw.wlan.fw_desc->totalLen = fw.wlan.fw_desc->dataSize = super->len;
 510         fw.wlan.fw_desc_data = fw.wlan.fw_desc->dataAddr = super;
 511         fw.wlan.fw_desc->nextAddr = fw.wlan.fw_desc->lastAddr =
 512                 fw.wlan.fw_desc;
 513         fw.wlan.fw_desc_callback = cb;
 514         wlan_tx(fw.wlan.fw_desc);
 515 }
 516
 517 static void wlan_send_buffered_ba(void)
 518 {
 519         struct carl9170_tx_ba_superframe *baf = &dma_mem.reserved.ba.ba;
 520         struct ieee80211_ba *ba = (struct ieee80211_ba *) &baf->f.ba;
 521         struct carl9170_bar_ctx *ctx;
 522
 523         if (likely(fw.wlan.ba_head_idx == fw.wlan.ba_tail_idx))
 524                 return;
 525
 526         /* there's no point to continue when the ba_desc is not available. */
 527         if (!fw.wlan.fw_desc_available)
 528                 return;
 529
 530         ctx = &fw.wlan.ba_cache[fw.wlan.ba_head_idx];
 531         fw.wlan.ba_head_idx++;
 532         fw.wlan.ba_head_idx %= CONFIG_CARL9170FW_BACK_REQS_NUM;
 533
 534         baf->s.len = sizeof(struct carl9170_tx_superdesc) +
 535                      sizeof(struct ar9170_tx_hwdesc) +
 536                      sizeof(struct ieee80211_ba);
 537         baf->s.ri[0].tries = 1;
 538         baf->s.cookie = 0;
 539         baf->s.queue = AR9170_TXQ_VO;
 540         baf->f.hdr.length = sizeof(struct ieee80211_ba) + FCS_LEN;
 541
 542         /* HW Duration / Backoff */
 543         baf->f.hdr.mac.backoff = 1;
 544         baf->f.hdr.mac.hw_duration = 1;
 545
 546         /* take the TX rate from the RX'd BAR */
 547         baf->f.hdr.phy.set = ctx->phy;
 548         baf->f.hdr.phy.tx_power = 29; /* 14.5 dBm */
 549
 550         /* format outgoing BA */
 551         ba->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_NULLFUNC);
 552         ba->duration = cpu_to_le16(0);
 553         memcpy(ba->ta, ctx->ta, 6);
 554         memcpy(ba->ra, ctx->ra, 6);
 555
 556         /*
 557          * Unfortunately, we cannot look into the hardware's scoreboard.
 558          * Therefore we have to proceed as described in 802.11n 9.10.7.5
 559          * and send a null BlockAck.
 560          */
 561         memset(ba->bitmap, 0x0, sizeof(ba->bitmap));
 562
 563         /*
 564          * NB:
 565          * not entirely sure if this is 100% correct?!
 566          */
 567         ba->control = ctx->control | cpu_to_le16(1);
 568         ba->start_seq_num = ctx->start_seq_num;
 569         wlan_tx_fw(&baf->s, NULL);
 570 }
 571
 572 static struct carl9170_bar_ctx *wlan_get_bar_cache_buffer(void)
 573 {
 574         struct carl9170_bar_ctx *tmp;
 575
 576         tmp = &fw.wlan.ba_cache[fw.wlan.ba_tail_idx];
 577         fw.wlan.ba_tail_idx++;
 578         fw.wlan.ba_tail_idx %= CONFIG_CARL9170FW_BACK_REQS_NUM;
 579
 580         return tmp;
 581 }
 582
 583 static void handle_bar(struct dma_desc *desc, struct ieee80211_hdr *hdr,
 584                        unsigned int len, unsigned int mac_err)
 585 {
 586         struct ieee80211_bar *bar;
 587         struct carl9170_bar_ctx *ctx;
 588
 589         if (unlikely(mac_err)) {
 590                 /*
 591                  * This check does a number of things:
 592                  * 1. checks if the frame is in good nick
 593                  * 2. checks if the RA (MAC) matches
 594                  */
 595                 return ;
 596         }
 597
 598         if (unlikely(len < (sizeof(struct ieee80211_bar) + FCS_LEN))) {
 599                 /*
 600                  * Sneaky, corrupted BARs... but not with us!
 601                  */
 602
 603                 return ;
 604         }
 605
 606         bar = (void *) hdr;
 607
 608         if ((bar->control & cpu_to_le16(IEEE80211_BAR_CTRL_MULTI_TID)) ||
 609             !(bar->control & cpu_to_le16(IEEE80211_BAR_CTRL_CBMTID_COMPRESSED_BA))) {
 610                 /* not implemented yet */
 611
 612                 return ;
 613         }
 614
 615         ctx = wlan_get_bar_cache_buffer();
 616
 617         /* Brilliant! The BAR provides all necessary MACs! */
 618         memcpy(ctx->ra, bar->ta, 6);
 619         memcpy(ctx->ta, bar->ra, 6);
 620
 621         /*
 622          * NB:
 623          * not entirely sure if this is 100% correct to force the
 624          * imm ack bit or not...
 625          */
 626         ctx->control = bar->control | cpu_to_le16(1);
 627         ctx->start_seq_num = bar->start_seq_num;
 628         ctx->phy = ar9170_rx_to_phy(desc);
 629         if (unlikely(!ctx->phy)) {
 630                 /* provide a backup, in case ar9170_rx_to_phy fails */
 631                 ctx->phy = cpu_to_le32(0x2cc301);
 632         }
 633 }
 634
 635 static void wlan_check_rx_overrun(void)
 636 {
 637         uint32_t overruns, total;
 638
 639         fw.tally.rx_total += total = get(AR9170_MAC_REG_RX_TOTAL);
 640         fw.tally.rx_overrun += overruns = get(AR9170_MAC_REG_RX_OVERRUN);
 641         if (unlikely(overruns)) {
 642                 if (overruns == total) {
 643                         DBG("RX Overrun");
 644                         fw.wlan.mac_reset++;
 645                 }
 646
 647                 wlan_trigger(AR9170_DMA_TRIGGER_RXQ);
 648         }
 649 }
 650
 651 static unsigned int wlan_rx_filter(struct dma_desc *desc)
 652 {
 653         struct ieee80211_hdr *hdr;
 654         unsigned int data_len;
 655         unsigned int rx_filter;
 656         unsigned int mac_err;
 657
 658         data_len = ar9170_get_rx_mpdu_len(desc);
 659         mac_err = ar9170_get_rx_macstatus_error(desc);
 660
 661 #define AR9170_RX_ERROR_BAD (AR9170_RX_ERROR_FCS | AR9170_RX_ERROR_PLCP)
 662
 663         if (unlikely(data_len < (4 + 6 + FCS_LEN) ||
 664             desc->totalLen > CONFIG_CARL9170FW_RX_FRAME_LEN) ||
 665             mac_err & AR9170_RX_ERROR_BAD) {
 666                 /*
 667                  * This frame is too damaged to do anything
 668                  * useful with it.
 669                  */
 670
 671                 return CARL9170_RX_FILTER_BAD;
 672         }
 673
 674         rx_filter = 0;
 675         if (mac_err & AR9170_RX_ERROR_WRONG_RA)
 676                 rx_filter |= CARL9170_RX_FILTER_OTHER_RA;
 677
 678         if (mac_err & AR9170_RX_ERROR_DECRYPT)
 679                 rx_filter |= CARL9170_RX_FILTER_DECRY_FAIL;
 680
 681         hdr = ar9170_get_rx_i3e(desc);
 682         if (likely(ieee80211_is_data(hdr->frame_control))) {
 683                 rx_filter |= CARL9170_RX_FILTER_DATA;
 684         } else if (ieee80211_is_ctl(hdr->frame_control)) {
 685                 switch (le16_to_cpu(hdr->frame_control) & IEEE80211_FCTL_STYPE) {
 686                 case IEEE80211_STYPE_BACK_REQ:
 687                         handle_bar(desc, hdr, data_len, mac_err);
 688                         /* fallthrough */
 689                         rx_filter |= CARL9170_RX_FILTER_CTL_BACKR;
 690                         break;
 691                 case IEEE80211_STYPE_PSPOLL:
 692                         rx_filter |= CARL9170_RX_FILTER_CTL_PSPOLL;
 693                         break;
 694                 default:
 695                         rx_filter |= CARL9170_RX_FILTER_CTL_OTHER;
 696                         break;
 697                 }
 698         } else {
 699                 /* ieee80211_is_mgmt */
 700                 rx_filter |= CARL9170_RX_FILTER_MGMT;
 701         }
 702
 703         if (unlikely(fw.suspend_mode == CARL9170_HOST_SUSPENDED)) {
 704                 wol_rx(rx_filter, hdr, min(data_len,
 705                         (unsigned int)AR9170_BLOCK_SIZE));
 706         }
 707
 708 #undef AR9170_RX_ERROR_BAD
 709
 710         return rx_filter;
 711 }
 712
 713 static void handle_rx(void)
 714 {
 715         struct dma_desc *desc;
 716
 717         for_each_desc_not_bits(desc, &fw.wlan.rx_queue, AR9170_OWN_BITS_HW) {
 718                 if (!(wlan_rx_filter(desc) & fw.wlan.rx_filter)) {
 719                         dma_put(&fw.pta.up_queue, desc);
 720                         up_trigger();
 721                 } else {
 722                         dma_reclaim(&fw.wlan.rx_queue, desc);
 723                         wlan_trigger(AR9170_DMA_TRIGGER_RXQ);
 724                 }
 725         }
 726 }
 727
 728 #ifdef CONFIG_CARL9170FW_CAB_QUEUE
 729 void wlan_cab_flush_queue(const unsigned int vif)
 730 {
 731         struct dma_queue *cab_queue = &fw.wlan.cab_queue[vif];
 732         struct dma_desc *desc;
 733
 734         /* move queued frames into the main tx queues */
 735         for_each_desc(desc, cab_queue) {
 736                 struct carl9170_tx_superframe *super = get_super(desc);
 737                 if (!queue_empty(cab_queue)) {
 738                         /*
 739                          * Set MOREDATA flag for all,
 740                          * but the last queued frame.
 741                          * see: 802.11-2007 11.2.1.5 f)
 742                          *
 743                          * This is actually the reason to why
 744                          * we need to prevent the reentry.
 745                          */
 746
 747                         super->f.data.i3e.frame_control |=
 748                                 cpu_to_le16(IEEE80211_FCTL_MOREDATA);
 749                 } else {
 750                         super->f.data.i3e.frame_control &=
 751                                 cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
 752                 }
 753
 754                 /* ready to roll! */
 755                 _wlan_tx(desc);
 756                 __wlan_tx(desc);
 757                 wlan_trigger(BIT(super->s.queue));
 758         }
 759 }
 760
 761 static uint8_t *beacon_find_ie(uint8_t ie, void *addr,
 762                                const unsigned int len)
 763 {
 764         struct ieee80211_mgmt *mgmt = addr;
 765         uint8_t *pos, *end;
 766
 767         pos = mgmt->u.beacon.variable;
 768         end = (uint8_t *) ((unsigned long)mgmt + (len - FCS_LEN));
 769         while (pos < end) {
 770                 if (pos + 2 + pos[1] > end)
 771                         return NULL;
 772
 773                 if (pos[0] == ie)
 774                         return pos;
 775
 776                 pos += pos[1] + 2;
 777         }
 778
 779         return NULL;
 780 }
 781
 782 void wlan_modify_beacon(const unsigned int vif,
 783         const unsigned int addr, const unsigned int len)
 784 {
 785         uint8_t *_ie;
 786         struct ieee80211_tim_ie *ie;
 787
 788         _ie = beacon_find_ie(WLAN_EID_TIM, (void *)addr, len);
 789         if (likely(_ie)) {
 790                 ie = (struct ieee80211_tim_ie *) &_ie[2];
 791
 792                 if (!queue_empty(&fw.wlan.cab_queue[vif]) && (ie->dtim_count == 0)) {
 793                         /* schedule DTIM transfer */
 794                         fw.wlan.cab_flush_trigger[vif] = CARL9170_CAB_TRIGGER_ARMED;
 795                 } else if ((fw.wlan.cab_queue_len[vif] == 0) && (fw.wlan.cab_flush_trigger[vif])) {
 796                         /* undo all chances to the beacon structure */
 797                         ie->bitmap_ctrl &= ~0x1;
 798                         fw.wlan.cab_flush_trigger[vif] = CARL9170_CAB_TRIGGER_EMPTY;
 799                 }
 800
 801                 /* Triggered by CARL9170_CAB_TRIGGER_ARMED || CARL9170_CAB_TRIGGER_DEFER */
 802                 if (fw.wlan.cab_flush_trigger[vif]) {
 803                         /* Set the almighty Multicast Traffic Indication Bit. */
 804                         ie->bitmap_ctrl |= 0x1;
 805                 }
 806         }
 807
 808         /*
 809          * Ideally, the sequence number should be assigned by the TX arbiter
 810          * hardware. But AFAIK that's not possible, so we have to go for the
 811          * next best thing and write it into the beacon fifo during the open
 812          * beacon update window.
 813          */
 814
 815         wlan_assign_seq((struct ieee80211_hdr *)addr, vif);
 816 }
 817
 818 static void wlan_send_buffered_cab(void)
 819 {
 820         unsigned int i;
 821
 822         for (i = 0; i < CARL9170_INTF_NUM; i++) {
 823                 if (unlikely(fw.wlan.cab_flush_trigger[i] == CARL9170_CAB_TRIGGER_ARMED)) {
 824                         /*
 825                          * This is hardcoded into carl9170usb driver.
 826                          *
 827                          * The driver must set the PRETBTT event to beacon_interval -
 828                          * CARL9170_PRETBTT_KUS (usually 6) Kus.
 829                          *
 830                          * But still, we can only do so much about 802.11-2007 9.3.2.1 &
 831                          * 11.2.1.6. Let's hope the current solution is adequate enough.
 832                          */
 833
 834                         if (is_after_msecs(fw.wlan.cab_flush_time, (CARL9170_TBTT_DELTA))) {
 835                                 wlan_cab_flush_queue(i);
 836
 837                                 /*
 838                                  * This prevents the code from sending new BC/MC frames
 839                                  * which were queued after the previous buffered traffic
 840                                  * has been sent out... They will have to wait until the
 841                                  * next DTIM beacon comes along.
 842                                  */
 843                                 fw.wlan.cab_flush_trigger[i] = CARL9170_CAB_TRIGGER_DEFER;
 844                         }
 845                 }
 846
 847         }
 848 }
 849 #endif /* CONFIG_CARL9170FW_CAB_QUEUE */
 850
 851 static void handle_beacon_config(void)
 852 {
 853         uint32_t bcn_count;
 854
 855         bcn_count = get(AR9170_MAC_REG_BCN_COUNT);
 856         send_cmd_to_host(4, CARL9170_RSP_BEACON_CONFIG, 0x00,
 857                          (uint8_t *) &bcn_count);
 858 }
 859
 860 static void handle_pretbtt(void)
 861 {
 862 #ifdef CONFIG_CARL9170FW_CAB_QUEUE
 863         fw.wlan.cab_flush_time = get_clock_counter();
 864 #endif /* CONFIG_CARL9170FW_CAB_QUEUE */
 865
 866 #ifdef CONFIG_CARL9170FW_RADIO_FUNCTIONS
 867         rf_psm();
 868
 869         send_cmd_to_host(4, CARL9170_RSP_PRETBTT, 0x00,
 870                          (uint8_t *) &fw.phy.psm.state);
 871 #endif /* CONFIG_CARL9170FW_RADIO_FUNCTIONS */
 872 }
 873
 874 static void handle_atim(void)
 875 {
 876         send_cmd_to_host(0, CARL9170_RSP_ATIM, 0x00, NULL);
 877 }
 878
 879 #ifdef CONFIG_CARL9170FW_DEBUG
 880 static void handle_qos(void)
 881 {
 882         /*
 883          * What is the QoS Bit used for?
 884          * Is it only an indicator for TXOP & Burst, or
 885          * should we do something here?
 886          */
 887 }
 888
 889 static void handle_radar(void)
 890 {
 891         send_cmd_to_host(0, CARL9170_RSP_RADAR, 0x00, NULL);
 892 }
 893 #endif /* CONFIG_CARL9170FW_DEBUG */
 894
 895 static void wlan_janitor(void)
 896 {
 897 #ifdef CONFIG_CARL9170FW_CAB_QUEUE
 898         wlan_send_buffered_cab();
 899 #endif /* CONFIG_CARL9170FW_CAB_QUEUE */
 900
 901         wlan_send_buffered_tx_status();
 902
 903         wlan_send_buffered_ba();
 904
 905         wol_janitor();
 906 }
 907
 908 void handle_wlan(void)
 909 {
 910         uint32_t intr;
 911
 912         intr = get(AR9170_MAC_REG_INT_CTRL);
 913         /* ACK Interrupt */
 914         set(AR9170_MAC_REG_INT_CTRL, intr);
 915
 916 #define HANDLER(intr, flag, func)                       \
 917         do {                                            \
 918                 if ((intr & flag) != 0) {               \
 919                         func();                         \
 920                 }                                       \
 921         } while (0)
 922
 923         intr |= fw.wlan.soft_int;
 924         fw.wlan.soft_int = 0;
 925
 926         HANDLER(intr, AR9170_MAC_INT_PRETBTT, handle_pretbtt);
 927
 928         HANDLER(intr, AR9170_MAC_INT_ATIM, handle_atim);
 929
 930         HANDLER(intr, AR9170_MAC_INT_RXC, handle_rx);
 931
 932         HANDLER(intr, (AR9170_MAC_INT_TXC | AR9170_MAC_INT_RETRY_FAIL),
 933                 handle_tx_completion);
 934
 935 #ifdef CONFIG_CARL9170FW_DEBUG
 936         HANDLER(intr, AR9170_MAC_INT_QOS, handle_qos);
 937
 938         HANDLER(intr, AR9170_MAC_INT_RADAR, handle_radar);
 939 #endif /* CONFIG_CARL9170FW_DEBUG */
 940
 941         HANDLER(intr, AR9170_MAC_INT_CFG_BCN, handle_beacon_config);
 942
 943         if (unlikely(intr))
 944                 DBG("Unhandled Interrupt %x\n", (unsigned int) intr);
 945
 946         wlan_janitor();
 947
 948 #undef HANDLER
 949 }
 950
 951 enum {
 952         CARL9170FW_TX_MAC_BUMP = 4,
 953         CARL9170FW_TX_MAC_DEBUG = 6,
 954         CARL9170FW_TX_MAC_RESET = 7,
 955 };
 956
 957 static void wlan_check_hang(void)
 958 {
 959         struct dma_desc *desc;
 960         int i;
 961
 962         for (i = AR9170_TXQ_SPECIAL; i >= AR9170_TXQ0; i--) {
 963                 if (queue_empty(&fw.wlan.tx_queue[i])) {
 964                         /* Nothing to do here... move along */
 965                         continue;
 966                 }
 967
 968                 /* fetch the current DMA queue position */
 969                 desc = (struct dma_desc *)get_wlan_txq_addr(i);
 970
 971                 /* Stuck frame detection */
 972                 if (unlikely(DESC_PAYLOAD(desc) == fw.wlan.last_super[i])) {
 973                         fw.wlan.last_super_num[i]++;
 974
 975                         if (unlikely(fw.wlan.last_super_num[i] >= CARL9170FW_TX_MAC_RESET)) {
 976                                 /*
 977                                  * schedule MAC reset (aka OFF/ON => dead)
 978                                  *
 979                                  * This will almost certainly kill
 980                                  * the device for good, but it's the
 981                                  * recommended thing to do...
 982                                  */
 983
 984                                 fw.wlan.mac_reset++;
 985                         }
 986
 987 #ifdef CONFIG_CARL9170FW_DEBUG
 988                         if (unlikely(fw.wlan.last_super_num[i] >= CARL9170FW_TX_MAC_DEBUG)) {
 989                                 /*
 990                                  * Sigh, the queue is almost certainly
 991                                  * dead. Dump the queue content to the
 992                                  * user, maybe we find out why it got
 993                                  * so stuck.
 994                                  */
 995
 996                                 wlan_dump_queue(i);
 997                         }
 998 #endif /* CONFIG_CARL9170FW_DEBUG */
 999
1000 #ifdef CONFIG_CARL9170FW_DMA_QUEUE_BUMP
1001                         if (unlikely(fw.wlan.last_super_num[i] >= CARL9170FW_TX_MAC_BUMP)) {
1002                                 /*
1003                                  * Hrrm, bump the queue a bit.
1004                                  * maybe this will get it going again.
1005                                  */
1006
1007                                 wlan_dma_bump(i);
1008                                 wlan_trigger(BIT(i));
1009                         }
1010 #endif /* CONFIG_CARL9170FW_DMA_QUEUE_BUMP */
1011                 } else {
1012                         /* Nothing stuck */
1013                         fw.wlan.last_super[i] = DESC_PAYLOAD(desc);
1014                         fw.wlan.last_super_num[i] = 0;
1015                 }
1016         }
1017 }
1018
1019 #ifdef CONFIG_CARL9170FW_FW_MAC_RESET
1020 /*
1021  * NB: Resetting the MAC is a two-edged sword.
1022  * On most occasions, it does what it is supposed to do.
1023  * But there is a chance that this will make it
1024  * even worse and the radio dies silently.
1025  */
1026 static void wlan_mac_reset(void)
1027 {
1028         uint32_t val;
1029         uint32_t agg_wait_counter;
1030         uint32_t agg_density;
1031         uint32_t bcn_start_addr;
1032         uint32_t rctl, rcth;
1033         uint32_t cam_mode;
1034         uint32_t ack_power;
1035         uint32_t rts_cts_tpc;
1036         uint32_t rts_cts_rate;
1037         int i;
1038
1039 #ifdef CONFIG_CARL9170FW_RADIO_FUNCTIONS
1040         uint32_t rx_BB;
1041 #endif /* CONFIG_CARL9170FW_RADIO_FUNCTIONS */
1042
1043 #ifdef CONFIG_CARL9170FW_NOISY_MAC_RESET
1044         INFO("MAC RESET");
1045 #endif /* CONFIG_CARL9170FW_NOISY_MAC_RESET */
1046
1047         /* Save aggregation parameters */
1048         agg_wait_counter = get(AR9170_MAC_REG_AMPDU_FACTOR);
1049         agg_density = get(AR9170_MAC_REG_AMPDU_DENSITY);
1050
1051         bcn_start_addr = get(AR9170_MAC_REG_BCN_ADDR);
1052
1053         cam_mode = get(AR9170_MAC_REG_CAM_MODE);
1054         rctl = get(AR9170_MAC_REG_CAM_ROLL_CALL_TBL_L);
1055         rcth = get(AR9170_MAC_REG_CAM_ROLL_CALL_TBL_H);
1056
1057         ack_power = get(AR9170_MAC_REG_ACK_TPC);
1058         rts_cts_tpc = get(AR9170_MAC_REG_RTS_CTS_TPC);
1059         rts_cts_rate = get(AR9170_MAC_REG_RTS_CTS_RATE);
1060
1061 #ifdef CONFIG_CARL9170FW_RADIO_FUNCTIONS
1062         /* 0x1c8960 write only */
1063         rx_BB = get(AR9170_PHY_REG_SWITCH_CHAIN_0);
1064 #endif /* CONFIG_CARL9170FW_RADIO_FUNCTIONS */
1065
1066         /* TX/RX must be stopped by now */
1067         val = get(AR9170_MAC_REG_POWER_STATE_CTRL);
1068
1069         val |= AR9170_MAC_POWER_STATE_CTRL_RESET;
1070
1071         /*
1072          * Manipulate CCA threshold to stop transmission
1073          *
1074          * set(AR9170_PHY_REG_CCA_THRESHOLD, 0x300);
1075          */
1076
1077         /*
1078          * check Rx state in 0(idle) 9(disable)
1079          *
1080          * chState = (get(AR9170_MAC_REG_MISC_684) >> 16) & 0xf;
1081          * while( (chState != 0) && (chState != 9)) {
1082          *      chState = (get(AR9170_MAC_REG_MISC_684) >> 16) & 0xf;
1083          * }
1084          */
1085
1086         set(AR9170_MAC_REG_POWER_STATE_CTRL, val);
1087
1088         delay(2);
1089
1090         /* Restore aggregation parameters */
1091         set(AR9170_MAC_REG_AMPDU_FACTOR, agg_wait_counter);
1092         set(AR9170_MAC_REG_AMPDU_DENSITY, agg_density);
1093
1094         set(AR9170_MAC_REG_BCN_ADDR, bcn_start_addr);
1095         set(AR9170_MAC_REG_CAM_MODE, cam_mode);
1096         set(AR9170_MAC_REG_CAM_ROLL_CALL_TBL_L, rctl);
1097         set(AR9170_MAC_REG_CAM_ROLL_CALL_TBL_H, rcth);
1098
1099         set(AR9170_MAC_REG_RTS_CTS_TPC, rts_cts_tpc);
1100         set(AR9170_MAC_REG_ACK_TPC, ack_power);
1101         set(AR9170_MAC_REG_RTS_CTS_RATE, rts_cts_rate);
1102
1103 #ifdef CONFIG_CARL9170FW_RADIO_FUNCTIONS
1104         set(AR9170_PHY_REG_SWITCH_CHAIN_2, rx_BB);
1105 #endif /* CONFIG_CARL9170FW_RADIO_FUNCTIONS */
1106
1107         /*
1108          * Manipulate CCA threshold to resume transmission
1109          *
1110          * set(AR9170_PHY_REG_CCA_THRESHOLD, 0x0);
1111          */
1112
1113         val = AR9170_DMA_TRIGGER_RXQ;
1114         /* Reinitialize all WLAN TX DMA queues. */
1115         for (i = AR9170_TXQ_SPECIAL; i >= AR9170_TXQ0; i--) {
1116                 struct dma_desc *iter;
1117
1118                 __for_each_desc_bits(iter, &fw.wlan.tx_queue[i], AR9170_OWN_BITS_SW);
1119
1120                 /* kill the stuck frame */
1121                 if (!is_terminator(&fw.wlan.tx_queue[i], iter) &&
1122                     fw.wlan.last_super_num[i] >= CARL9170FW_TX_MAC_RESET &&
1123                     fw.wlan.last_super[i] == DESC_PAYLOAD(iter)) {
1124                         struct carl9170_tx_superframe *super = get_super(iter);
1125
1126                         iter->status = AR9170_OWN_BITS_SW;
1127                         /*
1128                          * Mark the frame as failed.
1129                          * The BAFAIL flag allows the frame to sail through
1130                          * wlan_tx_status without much "unstuck" trouble.
1131                          */
1132                         iter->ctrl &= ~(AR9170_CTRL_FAIL);
1133                         iter->ctrl |= AR9170_CTRL_BAFAIL;
1134
1135                         super->s.cnt = CARL9170_TX_MAX_RATE_TRIES;
1136                         super->s.rix = CARL9170_TX_MAX_RETRY_RATES;
1137
1138                         fw.wlan.last_super_num[i] = 0;
1139                         fw.wlan.last_super[i] = NULL;
1140                         iter = iter->lastAddr->nextAddr;
1141                 }
1142
1143                 set_wlan_txq_dma_addr(i, (uint32_t) iter);
1144                 if (!is_terminator(&fw.wlan.tx_queue[i], iter))
1145                         val |= BIT(i);
1146
1147                 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]),
1148                      fw.wlan.tx_queue[i].head, fw.wlan.tx_queue[i].terminator,
1149                      get_wlan_txq_addr(i), iter, iter->ctrl, iter->status);
1150         }
1151
1152         fw.wlan.soft_int |= AR9170_MAC_INT_RXC | AR9170_MAC_INT_TXC |
1153                             AR9170_MAC_INT_RETRY_FAIL;
1154
1155         set(AR9170_MAC_REG_DMA_RXQ_ADDR, (uint32_t) fw.wlan.rx_queue.head);
1156         wlan_trigger(val);
1157 }
1158 #else
1159 static void wlan_mac_reset(void)
1160 {
1161         /* The driver takes care of reinitializing the device */
1162         BUG("MAC RESET");
1163 }
1164 #endif /* CONFIG_CARL9170FW_FW_MAC_RESET */
1165
1166 void __cold wlan_timer(void)
1167 {
1168         unsigned int cached_mac_reset;
1169
1170         cached_mac_reset = fw.wlan.mac_reset;
1171
1172         /* TX Queue Hang check */
1173         wlan_check_hang();
1174
1175         /* RX Overrun check */
1176         wlan_check_rx_overrun();
1177
1178         if (unlikely(fw.wlan.mac_reset >= CARL9170_MAC_RESET_RESET)) {
1179                 wlan_mac_reset();
1180                 fw.wlan.mac_reset = CARL9170_MAC_RESET_OFF;
1181         } else {
1182                 if (fw.wlan.mac_reset && cached_mac_reset == fw.wlan.mac_reset)
1183                         fw.wlan.mac_reset--;
1184         }
1185 }