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_end(unsigned int qidx)
 239 {
 240         struct carl9170_tx_superframe *ht_prev = fw.wlan.ampdu_prev[qidx];
 241
 242         fw.wlan.ampdu_prev[qidx] = NULL;
 243         if (ht_prev)
 244                 ht_prev->f.hdr.mac.ba_end = 1;
 245 }
 246
 247 static void wlan_tx_ampdu(struct carl9170_tx_superframe *super)
 248 {
 249         unsigned int qidx = super->s.queue;
 250         struct carl9170_tx_superframe *ht_prev = fw.wlan.ampdu_prev[qidx];
 251
 252         if (!super->f.hdr.mac.ampdu) {
 253                 wlan_tx_ampdu_end(qidx);
 254         } else {
 255                 fw.wlan.ampdu_prev[qidx] = super;
 256
 257                 if (ht_prev &&
 258                     !same_aggr(&super->f.data.i3e, &ht_prev->f.data.i3e))
 259                         ht_prev->f.hdr.mac.ba_end = 1;
 260                 else
 261                         super->f.hdr.mac.ba_end = 0;
 262         }
 263 }
 264
 265 /* for all tries */
 266 static void __wlan_tx(struct dma_desc *desc)
 267 {
 268         struct carl9170_tx_superframe *super = get_super(desc);
 269
 270         if (unlikely(super->s.fill_in_tsf)) {
 271                 struct ieee80211_mgmt *mgmt = (void *) &super->f.data.i3e;
 272                 uint32_t *tsf = (uint32_t *) &mgmt->u.probe_resp.timestamp;
 273
 274                 /*
 275                  * Truth be told: this is a hack.
 276                  *
 277                  * The *real* TSF is definitely going to be higher/older.
 278                  * But this hardware emulation code is head and shoulders
 279                  * above anything a driver can possibly do.
 280                  *
 281                  * (even, if it's got an accurate atomic clock source).
 282                  */
 283
 284                 read_tsf(tsf);
 285         }
 286
 287         wlan_tx_ampdu(super);
 288
 289 #if (defined CONFIG_CARL9170FW_LOOPBACK) || (defined CONFIG_CARL9170FW_DISCARD)
 290         wlan_tx_complete(super, true);
 291         unhide_super(desc);
 292 # ifdef CONFIG_CARL9170FW_LOOPBACK
 293         dma_put(&fw.pta.up_queue, desc);
 294         up_trigger();
 295 # elif CONFIG_CARL9170FW_DISCARD
 296         dma_reclaim(&fw.pta.down_queue, desc);
 297         down_trigger();
 298 # endif
 299 #else /* CONFIG_CARL9170FW_LOOPBACK */
 300
 301 # ifdef CONFIG_CARL9170FW_DEBUG
 302         BUG_ON(fw.phy.psm.state != CARL9170_PSM_WAKE);
 303 # endif /* CONFIG_CARL9170FW_DEBUG */
 304
 305         /* insert desc into the right queue */
 306         dma_put(&fw.wlan.tx_queue[super->s.queue], desc);
 307 #endif /* CONFIG_CARL9170FW_LOOPBACK */
 308 }
 309
 310 static void wlan_assign_seq(struct ieee80211_hdr *hdr, unsigned int vif)
 311 {
 312         hdr->seq_ctrl &= cpu_to_le16(~IEEE80211_SCTL_SEQ);
 313         hdr->seq_ctrl |= cpu_to_le16(fw.wlan.sequence[vif]);
 314
 315         if (!(hdr->seq_ctrl & cpu_to_le16(IEEE80211_SCTL_FRAG)))
 316                 fw.wlan.sequence[vif] += 0x10;
 317 }
 318
 319 /* prepares frame for the first transmission */
 320 static void _wlan_tx(struct dma_desc *desc)
 321 {
 322         struct carl9170_tx_superframe *super = get_super(desc);
 323
 324         if (unlikely(super->s.assign_seq))
 325                 wlan_assign_seq(&super->f.data.i3e, super->s.vif_id);
 326
 327         if (unlikely(super->s.ampdu_commit_density)) {
 328                 set(AR9170_MAC_REG_AMPDU_DENSITY,
 329                     MOD_VAL(AR9170_MAC_AMPDU_DENSITY,
 330                             get(AR9170_MAC_REG_AMPDU_DENSITY),
 331                             super->s.ampdu_density));
 332         }
 333
 334         if (unlikely(super->s.ampdu_commit_factor)) {
 335                 set(AR9170_MAC_REG_AMPDU_FACTOR,
 336                     MOD_VAL(AR9170_MAC_AMPDU_FACTOR,
 337                             get(AR9170_MAC_REG_AMPDU_FACTOR),
 338                             8 << super->s.ampdu_factor));
 339         }
 340
 341         __wlan_tx(desc);
 342 }
 343
 344 /* propagate transmission status back to the driver */
 345 static bool wlan_tx_status(struct dma_queue *queue,
 346                            struct dma_desc *desc)
 347 {
 348         struct carl9170_tx_superframe *super = get_super(desc);
 349         unsigned int qidx = super->s.queue;
 350         bool txfail = false, success;
 351
 352         success = true;
 353
 354         /* update hangcheck */
 355         fw.wlan.last_super_num[qidx] = 0;
 356
 357         if (!!(desc->ctrl & AR9170_CTRL_FAIL)) {
 358                 txfail = !!(desc->ctrl & AR9170_CTRL_TXFAIL);
 359
 360                 /* reset retry indicator flags */
 361                 desc->ctrl &= ~(AR9170_CTRL_TXFAIL | AR9170_CTRL_BAFAIL);
 362
 363                 if (wlan_tx_consume_retry(super)) {
 364                         /*
 365                          * retry for simple and aggregated 802.11 frames.
 366                          *
 367                          * Note: We must not mess up the original frame
 368                          * order.
 369                          */
 370
 371                         if (!super->f.hdr.mac.ampdu) {
 372                                 /*
 373                                  * 802.11 - 7.1.3.1.5.
 374                                  * set "Retry Field" for consecutive attempts
 375                                  *
 376                                  * Note: For AMPDU see:
 377                                  * 802.11n 9.9.1.6 "Retransmit Procedures"
 378                                  */
 379                                 super->f.data.i3e.frame_control |=
 380                                         cpu_to_le16(IEEE80211_FCTL_RETRY);
 381                         }
 382
 383                         if (txfail) {
 384                                 /* Normal TX Failure */
 385
 386                                 /* demise descriptor ownership back to the hardware */
 387                                 dma_rearm(desc);
 388
 389                                 /*
 390                                  * And this will get the queue going again.
 391                                  * To understand why: you have to get the HW
 392                                  * specs... But sadly I never saw them.
 393                                  */
 394                                 wlan_txunstuck(qidx);
 395
 396                                 /* abort cycle - this is necessary due to HW design */
 397                                 return false;
 398                         } else {
 399                                 /* (HT-) BlockACK failure */
 400
 401                                 /*
 402                                  * Unlink the failed attempt and put it into
 403                                  * the retry queue. The caller routine must
 404                                  * be aware of this so the frames don't get lost.
 405                                  */
 406
 407                                 dma_unlink_head(queue);
 408                                 dma_put(&fw.wlan.tx_retry, desc);
 409                                 return true;
 410                         }
 411                 } else {
 412                         /* out of frame attempts - discard frame */
 413                         success = false;
 414                 }
 415         }
 416
 417         dma_unlink_head(queue);
 418         if (txfail) {
 419                 /*
 420                  * Issue the queue bump,
 421                  * We need to do this in case this was the frame's last
 422                  * possible retry attempt and it unfortunately: it failed.
 423                  */
 424
 425                 wlan_txunstuck(qidx);
 426         }
 427
 428         unhide_super(desc);
 429
 430         if (unlikely(super == fw.wlan.fw_desc_data)) {
 431                 fw.wlan.fw_desc = desc;
 432                 fw.wlan.fw_desc_available = 1;
 433
 434                 if (fw.wlan.fw_desc_callback)
 435                         fw.wlan.fw_desc_callback(super, success);
 436
 437                 return true;
 438         }
 439
 440 #ifdef CONFIG_CARL9170FW_CAB_QUEUE
 441         if (unlikely(super->s.cab))
 442                 fw.wlan.cab_queue_len[super->s.vif_id]--;
 443 #endif /* CONFIG_CARL9170FW_CAB_QUEUE */
 444
 445         wlan_tx_complete(super, success);
 446
 447         /* recycle freed descriptors */
 448         dma_reclaim(&fw.pta.down_queue, desc);
 449         down_trigger();
 450         return true;
 451 }
 452
 453 static void handle_tx_completion(void)
 454 {
 455         struct dma_desc *desc;
 456         int i;
 457
 458         for (i = AR9170_TXQ_SPECIAL; i >= AR9170_TXQ0; i--) {
 459                 __while_desc_bits(desc, &fw.wlan.tx_queue[i], AR9170_OWN_BITS_SW) {
 460                         if (!wlan_tx_status(&fw.wlan.tx_queue[i], desc)) {
 461                                 /* termination requested. */
 462                                 break;
 463                         }
 464                 }
 465
 466                 for_each_desc(desc, &fw.wlan.tx_retry)
 467                         __wlan_tx(desc);
 468
 469                 wlan_tx_ampdu_end(i);
 470                 if (!queue_empty(&fw.wlan.tx_queue[i]))
 471                         wlan_trigger(BIT(i));
 472         }
 473 }
 474
 475 void __hot wlan_tx(struct dma_desc *desc)
 476 {
 477         struct carl9170_tx_superframe *super = DESC_PAYLOAD(desc);
 478
 479         /* initialize rate control struct */
 480         super->s.rix = 0;
 481         super->s.cnt = 1;
 482         hide_super(desc);
 483
 484 #ifdef CONFIG_CARL9170FW_CAB_QUEUE
 485         if (unlikely(super->s.cab)) {
 486                 fw.wlan.cab_queue_len[super->s.vif_id]++;
 487                 dma_put(&fw.wlan.cab_queue[super->s.vif_id], desc);
 488                 return;
 489         }
 490 #endif /* CONFIG_CARL9170FW_CAB_QUEUE */
 491
 492         _wlan_tx(desc);
 493         wlan_trigger(BIT(super->s.queue));
 494 }
 495
 496 void wlan_tx_fw(struct carl9170_tx_superdesc *super, fw_desc_callback_t cb)
 497 {
 498         if (!fw.wlan.fw_desc_available)
 499                 return;
 500
 501         fw.wlan.fw_desc_available = 0;
 502
 503         /* Format BlockAck */
 504         fw.wlan.fw_desc->ctrl = AR9170_CTRL_FS_BIT | AR9170_CTRL_LS_BIT;
 505         fw.wlan.fw_desc->status = AR9170_OWN_BITS_SW;
 506
 507         fw.wlan.fw_desc->totalLen = fw.wlan.fw_desc->dataSize = super->len;
 508         fw.wlan.fw_desc_data = fw.wlan.fw_desc->dataAddr = super;
 509         fw.wlan.fw_desc->nextAddr = fw.wlan.fw_desc->lastAddr =
 510                 fw.wlan.fw_desc;
 511         fw.wlan.fw_desc_callback = cb;
 512         wlan_tx(fw.wlan.fw_desc);
 513 }
 514
 515 static void wlan_send_buffered_ba(void)
 516 {
 517         struct carl9170_tx_ba_superframe *baf = &dma_mem.reserved.ba.ba;
 518         struct ieee80211_ba *ba = (struct ieee80211_ba *) &baf->f.ba;
 519         struct carl9170_bar_ctx *ctx;
 520
 521         if (likely(fw.wlan.ba_head_idx == fw.wlan.ba_tail_idx))
 522                 return;
 523
 524         /* there's no point to continue when the ba_desc is not available. */
 525         if (!fw.wlan.fw_desc_available)
 526                 return;
 527
 528         ctx = &fw.wlan.ba_cache[fw.wlan.ba_head_idx];
 529         fw.wlan.ba_head_idx++;
 530         fw.wlan.ba_head_idx %= CONFIG_CARL9170FW_BACK_REQS_NUM;
 531
 532         baf->s.len = sizeof(struct carl9170_tx_superdesc) +
 533                      sizeof(struct ar9170_tx_hwdesc) +
 534                      sizeof(struct ieee80211_ba);
 535         baf->s.ri[0].tries = 1;
 536         baf->s.cookie = 0;
 537         baf->s.queue = AR9170_TXQ_VO;
 538         baf->f.hdr.length = sizeof(struct ieee80211_ba) + FCS_LEN;
 539
 540         /* HW Duration / Backoff */
 541         baf->f.hdr.mac.backoff = 1;
 542         baf->f.hdr.mac.hw_duration = 1;
 543
 544         /* take the TX rate from the RX'd BAR */
 545         baf->f.hdr.phy.set = ctx->phy;
 546         baf->f.hdr.phy.tx_power = 29; /* 14.5 dBm */
 547
 548         /* format outgoing BA */
 549         ba->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_NULLFUNC);
 550         ba->duration = cpu_to_le16(0);
 551         memcpy(ba->ta, ctx->ta, 6);
 552         memcpy(ba->ra, ctx->ra, 6);
 553
 554         /*
 555          * Unfortunately, we cannot look into the hardware's scoreboard.
 556          * Therefore we have to proceed as described in 802.11n 9.10.7.5
 557          * and send a null BlockAck.
 558          */
 559         memset(ba->bitmap, 0x0, sizeof(ba->bitmap));
 560
 561         /*
 562          * NB:
 563          * not entirely sure if this is 100% correct?!
 564          */
 565         ba->control = ctx->control | cpu_to_le16(1);
 566         ba->start_seq_num = ctx->start_seq_num;
 567         wlan_tx_fw(&baf->s, NULL);
 568 }
 569
 570 static struct carl9170_bar_ctx *wlan_get_bar_cache_buffer(void)
 571 {
 572         struct carl9170_bar_ctx *tmp;
 573
 574         tmp = &fw.wlan.ba_cache[fw.wlan.ba_tail_idx];
 575         fw.wlan.ba_tail_idx++;
 576         fw.wlan.ba_tail_idx %= CONFIG_CARL9170FW_BACK_REQS_NUM;
 577
 578         return tmp;
 579 }
 580
 581 static void handle_bar(struct dma_desc *desc, struct ieee80211_hdr *hdr,
 582                        unsigned int len, unsigned int mac_err)
 583 {
 584         struct ieee80211_bar *bar;
 585         struct carl9170_bar_ctx *ctx;
 586
 587         if (unlikely(mac_err)) {
 588                 /*
 589                  * This check does a number of things:
 590                  * 1. checks if the frame is in good nick
 591                  * 2. checks if the RA (MAC) matches
 592                  */
 593                 return ;
 594         }
 595
 596         if (unlikely(len < (sizeof(struct ieee80211_bar) + FCS_LEN))) {
 597                 /*
 598                  * Sneaky, corrupted BARs... but not with us!
 599                  */
 600
 601                 return ;
 602         }
 603
 604         bar = (void *) hdr;
 605
 606         if ((bar->control & cpu_to_le16(IEEE80211_BAR_CTRL_MULTI_TID)) ||
 607             !(bar->control & cpu_to_le16(IEEE80211_BAR_CTRL_CBMTID_COMPRESSED_BA))) {
 608                 /* not implemented yet */
 609
 610                 return ;
 611         }
 612
 613         ctx = wlan_get_bar_cache_buffer();
 614
 615         /* Brilliant! The BAR provides all necessary MACs! */
 616         memcpy(ctx->ra, bar->ta, 6);
 617         memcpy(ctx->ta, bar->ra, 6);
 618
 619         /*
 620          * NB:
 621          * not entirely sure if this is 100% correct to force the
 622          * imm ack bit or not...
 623          */
 624         ctx->control = bar->control | cpu_to_le16(1);
 625         ctx->start_seq_num = bar->start_seq_num;
 626         ctx->phy = ar9170_rx_to_phy(desc);
 627         if (unlikely(!ctx->phy)) {
 628                 /* provide a backup, in case ar9170_rx_to_phy fails */
 629                 ctx->phy = cpu_to_le32(0x2cc301);
 630         }
 631 }
 632
 633 static void wlan_check_rx_overrun(void)
 634 {
 635         uint32_t overruns, total;
 636
 637         fw.tally.rx_total += total = get(AR9170_MAC_REG_RX_TOTAL);
 638         fw.tally.rx_overrun += overruns = get(AR9170_MAC_REG_RX_OVERRUN);
 639         if (unlikely(overruns)) {
 640                 if (overruns == total) {
 641                         DBG("RX Overrun");
 642                         fw.wlan.mac_reset++;
 643                 }
 644
 645                 wlan_trigger(AR9170_DMA_TRIGGER_RXQ);
 646         }
 647 }
 648
 649 static unsigned int wlan_rx_filter(struct dma_desc *desc)
 650 {
 651         struct ieee80211_hdr *hdr;
 652         unsigned int data_len;
 653         unsigned int rx_filter;
 654         unsigned int mac_err;
 655
 656         data_len = ar9170_get_rx_mpdu_len(desc);
 657         mac_err = ar9170_get_rx_macstatus_error(desc);
 658
 659 #define AR9170_RX_ERROR_BAD (AR9170_RX_ERROR_FCS | AR9170_RX_ERROR_PLCP)
 660
 661         if (unlikely(data_len < (4 + 6 + FCS_LEN) ||
 662             desc->totalLen > CONFIG_CARL9170FW_RX_FRAME_LEN) ||
 663             mac_err & AR9170_RX_ERROR_BAD) {
 664                 /*
 665                  * This frame is too damaged to do anything
 666                  * useful with it.
 667                  */
 668
 669                 return CARL9170_RX_FILTER_BAD;
 670         }
 671
 672         rx_filter = 0;
 673         if (mac_err & AR9170_RX_ERROR_WRONG_RA)
 674                 rx_filter |= CARL9170_RX_FILTER_OTHER_RA;
 675
 676         if (mac_err & AR9170_RX_ERROR_DECRYPT)
 677                 rx_filter |= CARL9170_RX_FILTER_DECRY_FAIL;
 678
 679         hdr = ar9170_get_rx_i3e(desc);
 680         if (likely(ieee80211_is_data(hdr->frame_control))) {
 681                 rx_filter |= CARL9170_RX_FILTER_DATA;
 682         } else if (ieee80211_is_ctl(hdr->frame_control)) {
 683                 switch (le16_to_cpu(hdr->frame_control) & IEEE80211_FCTL_STYPE) {
 684                 case IEEE80211_STYPE_BACK_REQ:
 685                         handle_bar(desc, hdr, data_len, mac_err);
 686                         /* fallthrough */
 687                         rx_filter |= CARL9170_RX_FILTER_CTL_BACKR;
 688                         break;
 689                 case IEEE80211_STYPE_PSPOLL:
 690                         rx_filter |= CARL9170_RX_FILTER_CTL_PSPOLL;
 691                         break;
 692                 default:
 693                         rx_filter |= CARL9170_RX_FILTER_CTL_OTHER;
 694                         break;
 695                 }
 696         } else {
 697                 /* ieee80211_is_mgmt */
 698                 rx_filter |= CARL9170_RX_FILTER_MGMT;
 699         }
 700
 701 #ifdef CONFIG_CARL9170FW_WOL
 702         if (unlikely(fw.suspend_mode == CARL9170_HOST_SUSPENDED)) {
 703                 wol_rx(rx_filter, hdr, min(data_len,
 704                         (unsigned int)AR9170_BLOCK_SIZE));
 705         }
 706 #endif /* CONFIG_CARL9170FW_WOL */
 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_trigger(BIT(super->s.queue));
 757         }
 758 }
 759
 760 static uint8_t *beacon_find_ie(uint8_t ie, void *addr,
 761                                const unsigned int len)
 762 {
 763         struct ieee80211_mgmt *mgmt = addr;
 764         uint8_t *pos, *end;
 765
 766         pos = mgmt->u.beacon.variable;
 767         end = (uint8_t *) ((unsigned long)mgmt + (len - FCS_LEN));
 768         while (pos < end) {
 769                 if (pos + 2 + pos[1] > end)
 770                         return NULL;
 771
 772                 if (pos[0] == ie)
 773                         return pos;
 774
 775                 pos += pos[1] + 2;
 776         }
 777
 778         return NULL;
 779 }
 780
 781 void wlan_modify_beacon(const unsigned int vif,
 782         const unsigned int addr, const unsigned int len)
 783 {
 784         uint8_t *_ie;
 785         struct ieee80211_tim_ie *ie;
 786
 787         _ie = beacon_find_ie(WLAN_EID_TIM, (void *)addr, len);
 788         if (likely(_ie)) {
 789                 ie = (struct ieee80211_tim_ie *) &_ie[2];
 790
 791                 if (!queue_empty(&fw.wlan.cab_queue[vif]) && (ie->dtim_count == 0)) {
 792                         /* schedule DTIM transfer */
 793                         fw.wlan.cab_flush_trigger[vif] = CARL9170_CAB_TRIGGER_ARMED;
 794                 } else if ((fw.wlan.cab_queue_len[vif] == 0) && (fw.wlan.cab_flush_trigger[vif])) {
 795                         /* undo all chances to the beacon structure */
 796                         ie->bitmap_ctrl &= ~0x1;
 797                         fw.wlan.cab_flush_trigger[vif] = CARL9170_CAB_TRIGGER_EMPTY;
 798                 }
 799
 800                 /* Triggered by CARL9170_CAB_TRIGGER_ARMED || CARL9170_CAB_TRIGGER_DEFER */
 801                 if (fw.wlan.cab_flush_trigger[vif]) {
 802                         /* Set the almighty Multicast Traffic Indication Bit. */
 803                         ie->bitmap_ctrl |= 0x1;
 804                 }
 805         }
 806
 807         /*
 808          * Ideally, the sequence number should be assigned by the TX arbiter
 809          * hardware. But AFAIK that's not possible, so we have to go for the
 810          * next best thing and write it into the beacon fifo during the open
 811          * beacon update window.
 812          */
 813
 814         wlan_assign_seq((struct ieee80211_hdr *)addr, vif);
 815 }
 816
 817 static void wlan_send_buffered_cab(void)
 818 {
 819         unsigned int i;
 820
 821         for (i = 0; i < CARL9170_INTF_NUM; i++) {
 822                 if (unlikely(fw.wlan.cab_flush_trigger[i] == CARL9170_CAB_TRIGGER_ARMED)) {
 823                         /*
 824                          * This is hardcoded into carl9170usb driver.
 825                          *
 826                          * The driver must set the PRETBTT event to beacon_interval -
 827                          * CARL9170_PRETBTT_KUS (usually 6) Kus.
 828                          *
 829                          * But still, we can only do so much about 802.11-2007 9.3.2.1 &
 830                          * 11.2.1.6. Let's hope the current solution is adequate enough.
 831                          */
 832
 833                         if (is_after_msecs(fw.wlan.cab_flush_time, (CARL9170_TBTT_DELTA))) {
 834                                 wlan_cab_flush_queue(i);
 835
 836                                 /*
 837                                  * This prevents the code from sending new BC/MC frames
 838                                  * which were queued after the previous buffered traffic
 839                                  * has been sent out... They will have to wait until the
 840                                  * next DTIM beacon comes along.
 841                                  */
 842                                 fw.wlan.cab_flush_trigger[i] = CARL9170_CAB_TRIGGER_DEFER;
 843                         }
 844                 }
 845
 846         }
 847 }
 848 #endif /* CONFIG_CARL9170FW_CAB_QUEUE */
 849
 850 static void handle_beacon_config(void)
 851 {
 852         uint32_t bcn_count;
 853
 854         bcn_count = get(AR9170_MAC_REG_BCN_COUNT);
 855         send_cmd_to_host(4, CARL9170_RSP_BEACON_CONFIG, 0x00,
 856                          (uint8_t *) &bcn_count);
 857 }
 858
 859 static void handle_pretbtt(void)
 860 {
 861 #ifdef CONFIG_CARL9170FW_CAB_QUEUE
 862         fw.wlan.cab_flush_time = get_clock_counter();
 863 #endif /* CONFIG_CARL9170FW_CAB_QUEUE */
 864
 865 #ifdef CONFIG_CARL9170FW_RADIO_FUNCTIONS
 866         rf_psm();
 867
 868         send_cmd_to_host(4, CARL9170_RSP_PRETBTT, 0x00,
 869                          (uint8_t *) &fw.phy.psm.state);
 870 #endif /* CONFIG_CARL9170FW_RADIO_FUNCTIONS */
 871 }
 872
 873 static void handle_atim(void)
 874 {
 875         send_cmd_to_host(0, CARL9170_RSP_ATIM, 0x00, NULL);
 876 }
 877
 878 #ifdef CONFIG_CARL9170FW_DEBUG
 879 static void handle_qos(void)
 880 {
 881         /*
 882          * What is the QoS Bit used for?
 883          * Is it only an indicator for TXOP & Burst, or
 884          * should we do something here?
 885          */
 886 }
 887
 888 static void handle_radar(void)
 889 {
 890         send_cmd_to_host(0, CARL9170_RSP_RADAR, 0x00, NULL);
 891 }
 892 #endif /* CONFIG_CARL9170FW_DEBUG */
 893
 894 static void wlan_janitor(void)
 895 {
 896 #ifdef CONFIG_CARL9170FW_CAB_QUEUE
 897         wlan_send_buffered_cab();
 898 #endif /* CONFIG_CARL9170FW_CAB_QUEUE */
 899
 900         wlan_send_buffered_tx_status();
 901
 902         wlan_send_buffered_ba();
 903
 904         wol_janitor();
 905 }
 906
 907 void handle_wlan(void)
 908 {
 909         uint32_t intr;
 910
 911         intr = get(AR9170_MAC_REG_INT_CTRL);
 912         /* ACK Interrupt */
 913         set(AR9170_MAC_REG_INT_CTRL, intr);
 914
 915 #define HANDLER(intr, flag, func)                       \
 916         do {                                            \
 917                 if ((intr & flag) != 0) {               \
 918                         func();                         \
 919                 }                                       \
 920         } while (0)
 921
 922         intr |= fw.wlan.soft_int;
 923         fw.wlan.soft_int = 0;
 924
 925         HANDLER(intr, AR9170_MAC_INT_PRETBTT, handle_pretbtt);
 926
 927         HANDLER(intr, AR9170_MAC_INT_ATIM, handle_atim);
 928
 929         HANDLER(intr, AR9170_MAC_INT_RXC, handle_rx);
 930
 931         HANDLER(intr, (AR9170_MAC_INT_TXC | AR9170_MAC_INT_RETRY_FAIL),
 932                 handle_tx_completion);
 933
 934 #ifdef CONFIG_CARL9170FW_DEBUG
 935         HANDLER(intr, AR9170_MAC_INT_QOS, handle_qos);
 936
 937         HANDLER(intr, AR9170_MAC_INT_RADAR, handle_radar);
 938 #endif /* CONFIG_CARL9170FW_DEBUG */
 939
 940         HANDLER(intr, AR9170_MAC_INT_CFG_BCN, handle_beacon_config);
 941
 942         if (unlikely(intr))
 943                 DBG("Unhandled Interrupt %x\n", (unsigned int) intr);
 944
 945         wlan_janitor();
 946
 947 #undef HANDLER
 948 }
 949
 950 enum {
 951         CARL9170FW_TX_MAC_BUMP = 4,
 952         CARL9170FW_TX_MAC_DEBUG = 6,
 953         CARL9170FW_TX_MAC_RESET = 7,
 954 };
 955
 956 static void wlan_check_hang(void)
 957 {
 958         struct dma_desc *desc;
 959         int i;
 960
 961         for (i = AR9170_TXQ_SPECIAL; i >= AR9170_TXQ0; i--) {
 962                 if (queue_empty(&fw.wlan.tx_queue[i])) {
 963                         /* Nothing to do here... move along */
 964                         continue;
 965                 }
 966
 967                 /* fetch the current DMA queue position */
 968                 desc = (struct dma_desc *)get_wlan_txq_addr(i);
 969
 970                 /* Stuck frame detection */
 971                 if (unlikely(DESC_PAYLOAD(desc) == fw.wlan.last_super[i])) {
 972                         fw.wlan.last_super_num[i]++;
 973
 974                         if (unlikely(fw.wlan.last_super_num[i] >= CARL9170FW_TX_MAC_RESET)) {
 975                                 /*
 976                                  * schedule MAC reset (aka OFF/ON => dead)
 977                                  *
 978                                  * This will almost certainly kill
 979                                  * the device for good, but it's the
 980                                  * recommended thing to do...
 981                                  */
 982
 983                                 fw.wlan.mac_reset++;
 984                         }
 985
 986 #ifdef CONFIG_CARL9170FW_DEBUG
 987                         if (unlikely(fw.wlan.last_super_num[i] >= CARL9170FW_TX_MAC_DEBUG)) {
 988                                 /*
 989                                  * Sigh, the queue is almost certainly
 990                                  * dead. Dump the queue content to the
 991                                  * user, maybe we find out why it got
 992                                  * so stuck.
 993                                  */
 994
 995                                 wlan_dump_queue(i);
 996                         }
 997 #endif /* CONFIG_CARL9170FW_DEBUG */
 998
 999 #ifdef CONFIG_CARL9170FW_DMA_QUEUE_BUMP
1000                         if (unlikely(fw.wlan.last_super_num[i] >= CARL9170FW_TX_MAC_BUMP)) {
1001                                 /*
1002                                  * Hrrm, bump the queue a bit.
1003                                  * maybe this will get it going again.
1004                                  */
1005
1006                                 wlan_dma_bump(i);
1007                                 wlan_trigger(BIT(i));
1008                         }
1009 #endif /* CONFIG_CARL9170FW_DMA_QUEUE_BUMP */
1010                 } else {
1011                         /* Nothing stuck */
1012                         fw.wlan.last_super[i] = DESC_PAYLOAD(desc);
1013                         fw.wlan.last_super_num[i] = 0;
1014                 }
1015         }
1016 }
1017
1018 #ifdef CONFIG_CARL9170FW_FW_MAC_RESET
1019 /*
1020  * NB: Resetting the MAC is a two-edged sword.
1021  * On most occasions, it does what it is supposed to do.
1022  * But there is a chance that this will make it
1023  * even worse and the radio dies silently.
1024  */
1025 static void wlan_mac_reset(void)
1026 {
1027         uint32_t val;
1028         uint32_t agg_wait_counter;
1029         uint32_t agg_density;
1030         uint32_t bcn_start_addr;
1031         uint32_t rctl, rcth;
1032         uint32_t cam_mode;
1033         uint32_t ack_power;
1034         uint32_t rts_cts_tpc;
1035         uint32_t rts_cts_rate;
1036         int i;
1037
1038 #ifdef CONFIG_CARL9170FW_RADIO_FUNCTIONS
1039         uint32_t rx_BB;
1040 #endif /* CONFIG_CARL9170FW_RADIO_FUNCTIONS */
1041
1042 #ifdef CONFIG_CARL9170FW_NOISY_MAC_RESET
1043         INFO("MAC RESET");
1044 #endif /* CONFIG_CARL9170FW_NOISY_MAC_RESET */
1045
1046         /* Save aggregation parameters */
1047         agg_wait_counter = get(AR9170_MAC_REG_AMPDU_FACTOR);
1048         agg_density = get(AR9170_MAC_REG_AMPDU_DENSITY);
1049
1050         bcn_start_addr = get(AR9170_MAC_REG_BCN_ADDR);
1051
1052         cam_mode = get(AR9170_MAC_REG_CAM_MODE);
1053         rctl = get(AR9170_MAC_REG_CAM_ROLL_CALL_TBL_L);
1054         rcth = get(AR9170_MAC_REG_CAM_ROLL_CALL_TBL_H);
1055
1056         ack_power = get(AR9170_MAC_REG_ACK_TPC);
1057         rts_cts_tpc = get(AR9170_MAC_REG_RTS_CTS_TPC);
1058         rts_cts_rate = get(AR9170_MAC_REG_RTS_CTS_RATE);
1059
1060 #ifdef CONFIG_CARL9170FW_RADIO_FUNCTIONS
1061         /* 0x1c8960 write only */
1062         rx_BB = get(AR9170_PHY_REG_SWITCH_CHAIN_0);
1063 #endif /* CONFIG_CARL9170FW_RADIO_FUNCTIONS */
1064
1065         /* TX/RX must be stopped by now */
1066         val = get(AR9170_MAC_REG_POWER_STATE_CTRL);
1067
1068         val |= AR9170_MAC_POWER_STATE_CTRL_RESET;
1069
1070         /*
1071          * Manipulate CCA threshold to stop transmission
1072          *
1073          * set(AR9170_PHY_REG_CCA_THRESHOLD, 0x300);
1074          */
1075
1076         /*
1077          * check Rx state in 0(idle) 9(disable)
1078          *
1079          * chState = (get(AR9170_MAC_REG_MISC_684) >> 16) & 0xf;
1080          * while( (chState != 0) && (chState != 9)) {
1081          *      chState = (get(AR9170_MAC_REG_MISC_684) >> 16) & 0xf;
1082          * }
1083          */
1084
1085         set(AR9170_MAC_REG_POWER_STATE_CTRL, val);
1086
1087         delay(2);
1088
1089         /* Restore aggregation parameters */
1090         set(AR9170_MAC_REG_AMPDU_FACTOR, agg_wait_counter);
1091         set(AR9170_MAC_REG_AMPDU_DENSITY, agg_density);
1092
1093         set(AR9170_MAC_REG_BCN_ADDR, bcn_start_addr);
1094         set(AR9170_MAC_REG_CAM_MODE, cam_mode);
1095         set(AR9170_MAC_REG_CAM_ROLL_CALL_TBL_L, rctl);
1096         set(AR9170_MAC_REG_CAM_ROLL_CALL_TBL_H, rcth);
1097
1098         set(AR9170_MAC_REG_RTS_CTS_TPC, rts_cts_tpc);
1099         set(AR9170_MAC_REG_ACK_TPC, ack_power);
1100         set(AR9170_MAC_REG_RTS_CTS_RATE, rts_cts_rate);
1101
1102 #ifdef CONFIG_CARL9170FW_RADIO_FUNCTIONS
1103         set(AR9170_PHY_REG_SWITCH_CHAIN_2, rx_BB);
1104 #endif /* CONFIG_CARL9170FW_RADIO_FUNCTIONS */
1105
1106         /*
1107          * Manipulate CCA threshold to resume transmission
1108          *
1109          * set(AR9170_PHY_REG_CCA_THRESHOLD, 0x0);
1110          */
1111
1112         val = AR9170_DMA_TRIGGER_RXQ;
1113         /* Reinitialize all WLAN TX DMA queues. */
1114         for (i = AR9170_TXQ_SPECIAL; i >= AR9170_TXQ0; i--) {
1115                 struct dma_desc *iter;
1116
1117                 __for_each_desc_bits(iter, &fw.wlan.tx_queue[i], AR9170_OWN_BITS_SW);
1118
1119                 /* kill the stuck frame */
1120                 if (!is_terminator(&fw.wlan.tx_queue[i], iter) &&
1121                     fw.wlan.last_super_num[i] >= CARL9170FW_TX_MAC_RESET &&
1122                     fw.wlan.last_super[i] == DESC_PAYLOAD(iter)) {
1123                         struct carl9170_tx_superframe *super = get_super(iter);
1124
1125                         iter->status = AR9170_OWN_BITS_SW;
1126                         /*
1127                          * Mark the frame as failed.
1128                          * The BAFAIL flag allows the frame to sail through
1129                          * wlan_tx_status without much "unstuck" trouble.
1130                          */
1131                         iter->ctrl &= ~(AR9170_CTRL_FAIL);
1132                         iter->ctrl |= AR9170_CTRL_BAFAIL;
1133
1134                         super->s.cnt = CARL9170_TX_MAX_RATE_TRIES;
1135                         super->s.rix = CARL9170_TX_MAX_RETRY_RATES;
1136
1137                         fw.wlan.last_super_num[i] = 0;
1138                         fw.wlan.last_super[i] = NULL;
1139                         iter = iter->lastAddr->nextAddr;
1140                 }
1141
1142                 set_wlan_txq_dma_addr(i, (uint32_t) iter);
1143                 if (!is_terminator(&fw.wlan.tx_queue[i], iter))
1144                         val |= BIT(i);
1145
1146                 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]),
1147                      fw.wlan.tx_queue[i].head, fw.wlan.tx_queue[i].terminator,
1148                      get_wlan_txq_addr(i), iter, iter->ctrl, iter->status);
1149         }
1150
1151         fw.wlan.soft_int |= AR9170_MAC_INT_RXC | AR9170_MAC_INT_TXC |
1152                             AR9170_MAC_INT_RETRY_FAIL;
1153
1154         set(AR9170_MAC_REG_DMA_RXQ_ADDR, (uint32_t) fw.wlan.rx_queue.head);
1155         wlan_trigger(val);
1156 }
1157 #else
1158 static void wlan_mac_reset(void)
1159 {
1160         /* The driver takes care of reinitializing the device */
1161         BUG("MAC RESET");
1162 }
1163 #endif /* CONFIG_CARL9170FW_FW_MAC_RESET */
1164
1165 void __cold wlan_timer(void)
1166 {
1167         unsigned int cached_mac_reset;
1168
1169         cached_mac_reset = fw.wlan.mac_reset;
1170
1171         /* TX Queue Hang check */
1172         wlan_check_hang();
1173
1174         /* RX Overrun check */
1175         wlan_check_rx_overrun();
1176
1177         if (unlikely(fw.wlan.mac_reset >= CARL9170_MAC_RESET_RESET)) {
1178                 wlan_mac_reset();
1179                 fw.wlan.mac_reset = CARL9170_MAC_RESET_OFF;
1180         } else {
1181                 if (fw.wlan.mac_reset && cached_mac_reset == fw.wlan.mac_reset)
1182                         fw.wlan.mac_reset--;
1183         }
1184 }