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, 2010 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
  35 static void wlan_txunstuck(unsigned int queue)
  36 {
  37         set_wlan_txq_dma_addr(queue, ((uint32_t) fw.wlan.tx_queue[queue].head) | 1);
  38         wlan_trigger(BIT(queue));
  39 }
  40
  41 static void wlan_txupdate(unsigned int queue)
  42 {
  43         set_wlan_txq_dma_addr(queue, ((uint32_t) fw.wlan.tx_queue[queue].head));
  44         wlan_trigger(BIT(queue));
  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
  73 #ifdef CONFIG_CARL9170FW_DEBUG
  74 static void wlan_dump_queue(unsigned int qidx)
  75 {
  76
  77         struct dma_desc *desc;
  78         struct carl9170_tx_superframe *super;
  79         int entries = 0;
  80
  81         __for_each_desc(desc, &fw.wlan.tx_queue[qidx]) {
  82                 super = get_super(desc);
  83                 DBG("%d: %p s:%x c:%x tl:%x ds:%x n:%p l:%p ", entries, desc,
  84                     desc->status, desc->ctrl, desc->totalLen,
  85                     desc->dataSize, desc->nextAddr, desc->lastAddr);
  86
  87                 DBG("c:%x tr:%d ri:%d l:%x m:%x p:%x fc:%x",
  88                     super->s.cookie, super->s.cnt, super->s.rix,
  89                     super->f.hdr.length, super->f.hdr.mac.set,
  90                     (unsigned int) le32_to_cpu(super->f.hdr.phy.set),
  91                     super->f.data.i3e.frame_control);
  92
  93                 entries++;
  94         }
  95
  96         desc = get_wlan_txq_addr(qidx);
  97
  98         DBG("Queue: %d: te:%d td:%d h:%p c:%p t:%p",
  99             qidx, entries, queue_len(&fw.wlan.tx_queue[qidx]),
 100             fw.wlan.tx_queue[qidx].head,
 101             desc, fw.wlan.tx_queue[qidx].terminator);
 102
 103         DBG("HW: t:%x s:%x ac:%x c:%x",
 104             (unsigned int) get(AR9170_MAC_REG_DMA_TRIGGER),
 105             (unsigned int) get(AR9170_MAC_REG_DMA_STATUS),
 106             (unsigned int) get(AR9170_MAC_REG_AMPDU_COUNT),
 107             (unsigned int) get(AR9170_MAC_REG_DMA_TXQX_ADDR_CURR));
 108 }
 109 #endif /* CONFIG_CARL9170FW_DEBUG */
 110
 111 static void wlan_send_buffered_tx_status(void)
 112 {
 113         unsigned int len;
 114
 115         while (fw.wlan.tx_status_pending) {
 116                 len = min((unsigned int)fw.wlan.tx_status_pending,
 117                           CARL9170_RSP_TX_STATUS_NUM);
 118                 len = min(len, CARL9170_TX_STATUS_NUM - fw.wlan.tx_status_head_idx);
 119
 120                 /*
 121                  * rather than memcpy each individual request into a large buffer,
 122                  * we _splice_ them all together.
 123                  *
 124                  * The only downside is however that we have to be careful around
 125                  * the edges of the tx_status_cache.
 126                  *
 127                  * Note:
 128                  * Each tx_status is about 2 bytes. However every command package
 129                  * must have a size which is a multiple of 4.
 130                  */
 131
 132                 send_cmd_to_host((len * sizeof(struct carl9170_tx_status) + 3) & ~3,
 133                                  CARL9170_RSP_TXCOMP, len, (void *)
 134                                  &fw.wlan.tx_status_cache[fw.wlan.tx_status_head_idx]);
 135
 136                 fw.wlan.tx_status_pending -= len;
 137                 fw.wlan.tx_status_head_idx += len;
 138                 fw.wlan.tx_status_head_idx %= CARL9170_TX_STATUS_NUM;
 139         }
 140 }
 141
 142 static struct carl9170_tx_status *wlan_get_tx_status_buffer(void)
 143 {
 144         struct carl9170_tx_status *tmp;
 145
 146         tmp = &fw.wlan.tx_status_cache[fw.wlan.tx_status_tail_idx++];
 147         fw.wlan.tx_status_tail_idx %= CARL9170_TX_STATUS_NUM;
 148
 149         if (fw.wlan.tx_status_pending == CARL9170_TX_STATUS_NUM)
 150                 wlan_send_buffered_tx_status();
 151
 152         fw.wlan.tx_status_pending++;
 153
 154         return tmp;
 155 }
 156
 157 /* generate _aggregated_ tx_status for the host */
 158 static void wlan_tx_complete(struct carl9170_tx_superframe *super,
 159                              bool txs)
 160 {
 161         struct carl9170_tx_status *status;
 162
 163         status = wlan_get_tx_status_buffer();
 164
 165         /*
 166          * The *unique* cookie and AC_ID is used by the driver for
 167          * frame lookup.
 168          */
 169         status->cookie = super->s.cookie;
 170         status->queue = super->s.queue;
 171
 172         /*
 173          * This field holds the number of tries of the rate in
 174          * the rate index field (rix).
 175          */
 176         status->rix = super->s.rix;
 177         status->tries = super->s.cnt;
 178         status->success = (txs) ? 1 : 0;
 179 }
 180
 181 static bool wlan_tx_consume_retry(struct carl9170_tx_superframe *super)
 182 {
 183         /* check if this was the last possible retry with this rate */
 184         if (unlikely(super->s.cnt >= super->s.ri[super->s.rix].tries)) {
 185                 /* end of the road - indicate tx failure */
 186                 if (unlikely(super->s.rix == CARL9170_TX_MAX_RETRY_RATES))
 187                         return false;
 188
 189                 /* check if there are alternative rates available */
 190                 if (!super->s.rr[super->s.rix].set)
 191                         return false;
 192
 193                 /* try next retry rate */
 194                 super->f.hdr.phy.set = super->s.rr[super->s.rix].set;
 195
 196                 /* finally - mark the old rate as USED */
 197                 super->s.rix++;
 198
 199                 /* update MAC flags */
 200                 super->f.hdr.mac.erp_prot = super->s.ri[super->s.rix].erp_prot;
 201                 super->f.hdr.mac.ampdu = super->s.ri[super->s.rix].ampdu;
 202
 203                 /* reinitialize try counter */
 204                 super->s.cnt = 1;
 205         } else {
 206                 /* just increase retry counter */
 207                 super->s.cnt++;
 208         }
 209
 210         return true;
 211 }
 212
 213 /* for all tries */
 214 static void __wlan_tx(struct dma_desc *desc)
 215 {
 216         struct carl9170_tx_superframe *super = get_super(desc);
 217 #ifdef CONFIG_CARL9170FW_NORMAL_TX_RX
 218         unsigned int queue = super->s.queue;
 219 #endif /* CONFIG_CARL9170FW_LOOPBACK */
 220
 221         if (unlikely(super->s.fill_in_tsf)) {
 222                 struct ieee80211_mgmt *mgmt = (void *) &super->f.data.i3e;
 223                 uint32_t *tsf = (uint32_t *) &mgmt->u.probe_resp.timestamp;
 224
 225                 /*
 226                  * Truth be told: this is a hack.
 227                  *
 228                  * The *real* TSF is definitely going to be higher/older.
 229                  * But this hardware emulation code is head and shoulders
 230                  * above anything a driver can possibly do.
 231                  *
 232                  * (even, if it's got an accurate atomic clock source).
 233                  */
 234
 235                 read_tsf(tsf);
 236         }
 237
 238 #if (defined CONFIG_CARL9170FW_LOOPBACK) || (defined CONFIG_CARL9170FW_DISCARD)
 239         wlan_tx_complete(super, true);
 240         unhide_super(desc);
 241 # ifdef CONFIG_CARL9170FW_LOOPBACK
 242         dma_put(&fw.pta.up_queue, desc);
 243         up_trigger();
 244 # elif CONFIG_CARL9170FW_DISCARD
 245         dma_reclaim(&fw.pta.down_queue, desc);
 246         down_trigger();
 247 # endif
 248 #else /* CONFIG_CARL9170FW_LOOPBACK */
 249
 250 # if ((defined CONFIG_CARL9170FW_DEBUG) && (defined CONFIG_CARL9170FW_PSM))
 251         BUG_ON(fw.phy.psm.state != CARL9170_PSM_WAKE);
 252 # endif /* CONFIG_CARL9170FW_DEBUG && CONFIG_CARL9170FW_PSM */
 253
 254         /* insert desc into the right queue */
 255         dma_put(&fw.wlan.tx_queue[queue], desc);
 256         wlan_trigger(BIT(queue));
 257 #endif /* CONFIG_CARL9170FW_LOOPBACK */
 258 }
 259
 260 /* prepares frame for the first transmission */
 261 static void _wlan_tx(struct dma_desc *desc)
 262 {
 263         struct carl9170_tx_superframe *super = get_super(desc);
 264
 265         if (unlikely(super->s.ampdu_commit_density)) {
 266                 set(AR9170_MAC_REG_AMPDU_DENSITY,
 267                     MOD_VAL(AR9170_MAC_AMPDU_DENSITY,
 268                             get(AR9170_MAC_REG_AMPDU_DENSITY),
 269                             super->s.ampdu_density));
 270         }
 271
 272         if (unlikely(super->s.ampdu_commit_factor)) {
 273                 set(AR9170_MAC_REG_AMPDU_FACTOR,
 274                     MOD_VAL(AR9170_MAC_AMPDU_FACTOR,
 275                             get(AR9170_MAC_REG_AMPDU_FACTOR),
 276                             8 << super->s.ampdu_factor));
 277         }
 278
 279         __wlan_tx(desc);
 280 }
 281
 282 /* propagate transmission status back to the driver */
 283 static bool wlan_tx_status(struct dma_queue *queue,
 284                            struct dma_desc *desc)
 285 {
 286         struct ar9170_tx_frame *frame = DESC_PAYLOAD(desc);
 287         struct carl9170_tx_superframe *super = get_super(desc);
 288         struct ieee80211_hdr *hdr = &super->f.data.i3e;
 289         unsigned int qidx = super->s.queue;
 290         bool txfail, success;
 291
 292         success = true;
 293
 294         if (!!(desc->ctrl & AR9170_CTRL_FAIL)) {
 295                 txfail = !!(desc->ctrl & AR9170_CTRL_TXFAIL);
 296
 297                 /* reset retry indicator flags */
 298                 desc->ctrl &= ~(AR9170_CTRL_TXFAIL | AR9170_CTRL_BAFAIL);
 299
 300                 if (wlan_tx_consume_retry(super)) {
 301                         /*
 302                          * retry for simple and aggregated 802.11 frames.
 303                          *
 304                          * Note: We must not mess up the original frame
 305                          * order.
 306                          */
 307
 308                         if (!frame->hdr.mac.ampdu) {
 309                                 /*
 310                                  * 802.11 - 7.1.3.1.5.
 311                                  * set "Retry Field" for consecutive attempts
 312                                  *
 313                                  * Note: For AMPDU see:
 314                                  * 802.11n 9.9.1.6 "Retransmit Procedures"
 315                                  */
 316
 317                                 hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_RETRY);
 318                         }
 319
 320                         if (txfail) {
 321                                 /* Normal TX Failure */
 322
 323                                 /* demise descriptor ownership back to the hardware */
 324                                 dma_rearm(desc);
 325
 326                                 /*
 327                                  * And this will get the queue going again.
 328                                  * To understand why: you have to get the HW
 329                                  * specs... But sadly I never saw them.
 330                                  */
 331                                 wlan_txunstuck(qidx);
 332
 333                                 /* abort cycle - this is necessary due to HW design */
 334                                 return false;
 335                         } else {
 336                                 /* (HT-) BlockACK failure */
 337
 338                                 /*
 339                                  * Unlink the failed attempt and put it into
 340                                  * the retry queue. The caller routine must
 341                                  * be aware of this so the frames don't get lost.
 342                                  */
 343
 344                                 dma_unlink_head(queue);
 345 #ifdef CONFIG_CARL9170FW_DELAYED_TX
 346                                 dma_put(&fw.wlan.tx_retry, desc);
 347 #else
 348                                 __wlan_tx(desc);
 349 #endif /* CONFIG_CARL9170FW_DELAYED_TX */
 350                                 return true;
 351                         }
 352                 } else {
 353                         /* out of frame attempts - discard frame */
 354                         success = false;
 355                 }
 356         }
 357
 358         dma_unlink_head(queue);
 359         if (txfail) {
 360                 /*
 361                  * Issue the queue bump,
 362                  * We need to do this in case this was the frame's last
 363                  * possible retry attempt and it unfortunately: it failed.
 364                  */
 365
 366                 wlan_txunstuck(qidx);
 367         }
 368
 369         unhide_super(desc);
 370
 371         /* update hangcheck */
 372         fw.wlan.last_tx_desc_num[qidx] = 0;
 373
 374 #ifdef CONFIG_CARL9170FW_HANDLE_BACK_REQ
 375         if (unlikely(super == (void *) &dma_mem.reserved.ba)) {
 376                 fw.wlan.ba_desc = desc;
 377                 fw.wlan.ba_desc_available = 1;
 378                 return true;
 379         }
 380 #endif /* CONFIG_CARL9170FW_HANDLE_BACK_REQ */
 381
 382         wlan_tx_complete(super, success);
 383
 384 #ifdef CONFIG_CARL9170FW_CAB_QUEUE
 385         if (unlikely(super->s.cab))
 386                 fw.wlan.cab_queue_len--;
 387 #endif /* CONFIG_CARL9170FW_CAB_QUEUE */
 388
 389         /* recycle freed descriptors */
 390         dma_reclaim(&fw.pta.down_queue, desc);
 391         down_trigger();
 392         return true;
 393 }
 394
 395 static void handle_tx_completion(void)
 396 {
 397         struct dma_desc *desc;
 398         unsigned int i;
 399
 400         for (i = 0; i < __AR9170_NUM_TX_QUEUES; i++) {
 401                 __while_desc_bits(desc, &fw.wlan.tx_queue[i], AR9170_OWN_BITS_SW) {
 402                         if (!wlan_tx_status(&fw.wlan.tx_queue[i], desc)) {
 403                                 /* termination requested. */
 404                                 break;
 405                         }
 406                 }
 407
 408 #ifdef CONFIG_CARL9170FW_DELAYED_TX
 409                 for_each_desc(desc, &fw.wlan.tx_retry)
 410                         __wlan_tx(desc);
 411
 412                 for_each_desc(desc, &fw.wlan.tx_delay[i])
 413                         _wlan_tx(desc);
 414 #endif /* CONFIG_CARL9170FW_DELAYED_TX */
 415         }
 416 }
 417
 418 void __hot wlan_tx(struct dma_desc *desc)
 419 {
 420         struct carl9170_tx_superframe *super = DESC_PAYLOAD(desc);
 421
 422         /* initialize rate control struct */
 423         super->s.rix = 0;
 424         super->s.cnt = 1;
 425         hide_super(desc);
 426
 427 #ifdef CONFIG_CARL9170FW_DELAYED_TX
 428         if (!queue_empty(&fw.wlan.tx_queue[super->s.queue])) {
 429                 dma_put(&fw.wlan.tx_delay[super->s.queue], desc);
 430                 return;
 431         }
 432 #endif /* CONFIG_CARL9170FW_DELAYED_TX */
 433
 434 #ifdef CONFIG_CARL9170FW_CAB_QUEUE
 435         if (unlikely(super->s.cab)) {
 436                 fw.wlan.cab_queue_len++;
 437                 dma_put(&fw.wlan.cab_queue, desc);
 438                 return;
 439         }
 440 #endif /* CONFIG_CARL9170FW_CAB_QUEUE */
 441
 442         _wlan_tx(desc);
 443 }
 444
 445 #ifdef CONFIG_CARL9170FW_HANDLE_BACK_REQ
 446 static void wlan_send_buffered_ba(void)
 447 {
 448         struct carl9170_tx_ba_superframe *baf = &dma_mem.reserved.ba.ba;
 449         struct ieee80211_ba *ba = (struct ieee80211_ba *) &baf->f.ba;
 450         struct carl9170_bar_ctx *ctx;
 451
 452         if (likely(fw.wlan.ba_head_idx == fw.wlan.ba_tail_idx))
 453                 return;
 454
 455         /* there's no point to continue when the ba_desc is not available. */
 456         if (!fw.wlan.ba_desc_available)
 457                 return;
 458
 459         ctx = &fw.wlan.ba_cache[fw.wlan.ba_head_idx % CONFIG_CARL9170FW_BACK_REQS_NUM];
 460         fw.wlan.ba_head_idx++;
 461
 462         /* Format BlockAck */
 463         fw.wlan.ba_desc->status = 0;
 464         fw.wlan.ba_desc->ctrl = AR9170_CTRL_FS_BIT | AR9170_CTRL_LS_BIT;
 465         fw.wlan.ba_desc_available = 0;
 466         fw.wlan.ba_desc->nextAddr = fw.wlan.ba_desc->lastAddr =
 467                 fw.wlan.ba_desc;
 468
 469         baf->s.len = fw.wlan.ba_desc->totalLen = fw.wlan.ba_desc->dataSize =
 470                 sizeof(struct carl9170_tx_superdesc) +
 471                 sizeof(struct ar9170_tx_hwdesc) +
 472                 sizeof(struct ieee80211_ba);
 473
 474         baf->s.ri[0].tries = 3;
 475         baf->s.queue = 0;
 476         baf->f.hdr.length = sizeof(struct ieee80211_ba) + FCS_LEN;
 477
 478         /* HW Duration / Backoff */
 479         baf->f.hdr.mac.backoff = 1;
 480         baf->f.hdr.mac.hw_duration = 1;
 481
 482         /* take the TX rate from the RX'd BAR */
 483         baf->f.hdr.phy.set = ctx->phy;
 484         baf->f.hdr.phy.tx_power = 29; /* 14.5 dBm */
 485
 486         /* format outgoing BA */
 487         ba->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_BACK);
 488         ba->duration = cpu_to_le16(0);
 489         memcpy(ba->ta, ctx->ta, 6);
 490         memcpy(ba->ra, ctx->ra, 6);
 491
 492         /*
 493          * Unfortunately, we cannot look into the hardware's scoreboard.
 494          * Therefore we have to proceed as described in 802.11n 9.10.7.5
 495          * and send a null BlockAck.
 496          */
 497         memset(ba->bitmap, 0x0, sizeof(ba->bitmap));
 498
 499         /*
 500          * NB:
 501          * not entirely sure if this is 100% correct?!
 502          */
 503         ba->control = ctx->control | cpu_to_le16(1);
 504         ba->start_seq_num = ctx->start_seq_num;
 505
 506         wlan_tx(fw.wlan.ba_desc);
 507 }
 508
 509 static struct carl9170_bar_ctx *wlan_get_bar_cache_buffer(void)
 510 {
 511         struct carl9170_bar_ctx *tmp;
 512
 513         /* expire oldest entry, if we ran out of ba_ctx' */
 514         if (fw.wlan.ba_head_idx + CONFIG_CARL9170FW_BACK_REQS_NUM < fw.wlan.ba_tail_idx)
 515                 fw.wlan.ba_head_idx++;
 516
 517         tmp = &fw.wlan.ba_cache[fw.wlan.ba_tail_idx % CONFIG_CARL9170FW_BACK_REQS_NUM];
 518         fw.wlan.ba_tail_idx++;
 519
 520         return tmp;
 521 }
 522
 523 static void handle_bar(struct dma_desc *desc)
 524 {
 525         struct ieee80211_hdr *hdr;
 526         struct ieee80211_bar *bar;
 527         struct carl9170_bar_ctx *ctx;
 528
 529         hdr = ar9170_get_rx_i3e(desc);
 530
 531         /* check if this is a BAR for us */
 532         if (likely(!ieee80211_is_back_req(hdr->frame_control)))
 533                 return ;
 534
 535         if (unlikely(ar9170_get_rx_macstatus_error(desc))) {
 536                 /*
 537                  * This check does a number of things:
 538                  * 1. checks if the frame is in good nick
 539                  * 2. checks if the RA (MAC) matches
 540                  */
 541                 return ;
 542         }
 543
 544         if (unlikely(ar9170_get_rx_mpdu_len(desc) <
 545             sizeof(struct ieee80211_bar))) {
 546                 /*
 547                  * Sneaky, corrupted BARs... but not with us!
 548                  */
 549
 550                 return ;
 551         }
 552
 553         bar = (void *) hdr;
 554
 555         if ((bar->control & cpu_to_le16(IEEE80211_BAR_CTRL_MULTI_TID)) ||
 556             !(bar->control & cpu_to_le16(IEEE80211_BAR_CTRL_CBMTID_COMPRESSED_BA))) {
 557                 /* not implemented yet */
 558
 559                 return ;
 560         }
 561
 562         ctx = wlan_get_bar_cache_buffer();
 563
 564         /* Brilliant! The BAR provides all necessary MACs! */
 565         memcpy(ctx->ra, bar->ta, 6);
 566         memcpy(ctx->ta, bar->ra, 6);
 567
 568         /*
 569          * NB:
 570          * not entirely sure if this is 100% correct to force the
 571          * imm ack bit or not...
 572          */
 573         ctx->control = bar->control | cpu_to_le16(1);
 574         ctx->start_seq_num = bar->start_seq_num;
 575         ctx->phy = ar9170_rx_to_phy(desc);
 576         if (unlikely(!ctx->phy)) {
 577                 /* provide a backup, in case ar9170_rx_to_phy fails */
 578                 ctx->phy = cpu_to_le32(0x2cc301);
 579         }
 580 }
 581 #endif /* CONFIG_CARL9170FW_HANDLE_BACK_REQ */
 582
 583 static void wlan_check_rx_overrun(void)
 584 {
 585         uint32_t overruns, total;
 586
 587         fw.wlan.rx_total += total = get(AR9170_MAC_REG_RX_TOTAL);
 588         fw.wlan.rx_overruns += overruns = get(AR9170_MAC_REG_RX_OVERRUN);
 589         if (unlikely(overruns)) {
 590                 if (overruns == total) {
 591                         DBG("RX Overrun");
 592                         fw.wlan.mac_reset++;
 593                 }
 594         }
 595 }
 596
 597 static void handle_rx(void)
 598 {
 599         struct dma_desc *desc;
 600
 601         wlan_check_rx_overrun();
 602
 603         for_each_desc_not_bits(desc, &fw.wlan.rx_queue, AR9170_OWN_BITS_HW) {
 604                 if (unlikely(desc->totalLen < 26 ||
 605                     desc->totalLen > CONFIG_CARL9170FW_RX_FRAME_LEN)) {
 606                         /*
 607                          * This frame is too damaged to do anything
 608                          * useful with it.
 609                          */
 610                         dma_reclaim(&fw.wlan.rx_queue, desc);
 611                         _wlan_trigger(AR9170_DMA_TRIGGER_RXQ);
 612                 } else {
 613 #ifdef CONFIG_CARL9170FW_HANDLE_BACK_REQ
 614                         handle_bar(desc);
 615 #endif /* CONFIG_CARL9170FW_HANDLE_BACK_REQ */
 616
 617                         dma_put(&fw.pta.up_queue, desc);
 618                         up_trigger();
 619                 }
 620         }
 621 }
 622
 623 #ifdef CONFIG_CARL9170FW_CAB_QUEUE
 624 static uint8_t *beacon_find_ie(uint8_t ie)
 625 {
 626         struct ieee80211_mgmt *mgmt = getp(AR9170_MAC_REG_BCN_ADDR);
 627         uint8_t *pos, *end;
 628         unsigned int len;
 629
 630         len = get(AR9170_MAC_REG_BCN_LENGTH);
 631
 632         if (len < FCS_LEN + sizeof(mgmt))
 633                 return NULL;
 634
 635         pos = mgmt->u.beacon.variable;
 636         end = (uint8_t *) ((unsigned long)mgmt + (len - FCS_LEN));
 637         while (pos < end) {
 638                 if (pos + 2 + pos[1] > end)
 639                         return NULL;
 640
 641                 if (pos[0] == ie)
 642                         return pos;
 643
 644                 pos += pos[1] + 2;
 645         }
 646
 647         return NULL;
 648 }
 649
 650 static void wlan_cab_flush_queue(void)
 651 {
 652         struct dma_desc *desc;
 653         uint8_t *_ie;
 654         struct ieee80211_tim_ie *ie;
 655
 656         /*
 657          * This prevents the code from sending new BC/MC frames
 658          * which were queued after the previous buffered traffic
 659          * has been sent out... They will have to wait until the
 660          * next DTIM beacon comes along.
 661          */
 662         if (unlikely(fw.wlan.cab_flush_trigger == CARL9170_CAB_TRIGGER_DEFER))
 663                 return ;
 664
 665         _ie = beacon_find_ie(WLAN_EID_TIM);
 666         if (unlikely(!_ie))
 667                 return ;
 668
 669         ie = (struct ieee80211_tim_ie *) &_ie[2];
 670
 671         /* Ideally, check here for == AR9170_CAB_TRIGGER_ARMED */
 672         if (fw.wlan.cab_flush_trigger) {
 673                 /* move queued frames into the main tx queues */
 674                 for_each_desc(desc, &fw.wlan.cab_queue) {
 675                         struct carl9170_tx_superframe *super = get_super(desc);
 676
 677                         if (!queue_empty(&fw.wlan.cab_queue)) {
 678                                 /*
 679                                  * Set MOREDATA flag for all,
 680                                  * but the last queued frame.
 681                                  * see: 802.11-2007 11.2.1.5 f)
 682                                  *
 683                                  * This is actually the reason to why
 684                                  * we need to prevent the reentry.
 685                                  */
 686
 687                                 super->f.data.i3e.frame_control |=
 688                                         cpu_to_le16(IEEE80211_FCTL_MOREDATA);
 689                         } else {
 690                                 super->f.data.i3e.frame_control &=
 691                                         cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
 692                         }
 693
 694                         /* ready to roll! */
 695                         _wlan_tx(desc);
 696                 }
 697         }
 698
 699         /* Transfer finished - waiting for tx status */
 700         fw.wlan.cab_flush_trigger = CARL9170_CAB_TRIGGER_DEFER;
 701 }
 702
 703 static void wlan_cab_modify_dtim_beacon(void)
 704 {
 705         uint8_t *_ie;
 706         struct ieee80211_tim_ie *ie;
 707
 708         _ie = beacon_find_ie(WLAN_EID_TIM);
 709         if (likely(_ie)) {
 710                 ie = (struct ieee80211_tim_ie *) &_ie[2];
 711
 712                 if (!queue_empty(&fw.wlan.cab_queue) && (ie->dtim_count == 0)) {
 713                         /* schedule DTIM transfer */
 714                         fw.wlan.cab_flush_trigger = CARL9170_CAB_TRIGGER_ARMED;
 715                 } else if ((fw.wlan.cab_queue_len == 0) && (fw.wlan.cab_flush_trigger)) {
 716                         /* undo all chances to the beacon structure */
 717                         ie->bitmap_ctrl &= ~0x1;
 718                         fw.wlan.cab_flush_trigger = CARL9170_CAB_TRIGGER_EMPTY;
 719                 }
 720
 721                 if (fw.wlan.cab_flush_trigger) {
 722                         /* Set the almighty Multicast Traffic Indication Bit. */
 723                         ie->bitmap_ctrl |= 0x1;
 724                 }
 725         }
 726 }
 727 #endif /* CONFIG_CARL9170FW_CAB_QUEUE */
 728
 729 static void handle_beacon_config(void)
 730 {
 731         uint32_t bcn_count;
 732
 733 #ifdef CONFIG_CARL9170FW_CAB_QUEUE
 734         /*
 735          * The application has now updated the relevant beacon data.
 736          * Now it should be the perfect time to apply the DTIM
 737          * multicast information.
 738          */
 739
 740         wlan_cab_modify_dtim_beacon();
 741 #endif /* CONFIG_CARL9170FW_CAB_QUEUE */
 742
 743         bcn_count = get(AR9170_MAC_REG_BCN_COUNT);
 744         send_cmd_to_host(4, CARL9170_RSP_BEACON_CONFIG, 0x00,
 745                          (uint8_t *) &bcn_count);
 746 }
 747
 748 static void handle_pretbtt(void)
 749 {
 750 #ifdef CONFIG_CARL9170FW_CAB_QUEUE
 751         fw.wlan.cab_flush_time = get_clock_counter();
 752 #endif /* CONFIG_CARL9170FW_CAB_QUEUE */
 753
 754 #ifdef CONFIG_CARL9170FW_PSM
 755         rf_psm();
 756
 757         send_cmd_to_host(4, CARL9170_RSP_PRETBTT, 0x00,
 758                          (uint8_t *) &fw.phy.psm.state);
 759 #else
 760         send_cmd_to_host(0, CARL9170_RSP_PRETBTT, 0x00, NULL);
 761 #endif /* CONFIG_CARL9170FW_PSM */
 762
 763 }
 764
 765 static void handle_atim(void)
 766 {
 767         send_cmd_to_host(0, CARL9170_RSP_ATIM, 0x00, NULL);
 768 }
 769
 770 #ifdef CONFIG_CARL9170FW_DEBUG
 771 static void handle_qos(void)
 772 {
 773         /*
 774          * What is the QoS Bit used for?
 775          * Is it only an indicator for TXOP & Burst, or
 776          * should we do something here?
 777          */
 778 }
 779
 780 static void handle_radar(void)
 781 {
 782         send_cmd_to_host(0, CARL9170_RSP_RADAR, 0x00, NULL);
 783 }
 784 #endif /* CONFIG_CARL9170FW_DEBUG */
 785
 786 static void wlan_janitor(void)
 787 {
 788 #ifdef CONFIG_CARL9170FW_CAB_QUEUE
 789         if (unlikely(fw.wlan.cab_flush_trigger)) {
 790                 /*
 791                  * This is hardcoded into carl9170usb driver.
 792                  *
 793                  * The driver must set the PRETBTT event to beacon_interval -
 794                  * CARL9170_PRETBTT_KUS (usually 6) Kus.
 795                  *
 796                  * But still, we can only do so much about 802.11-2007 9.3.2.1 &
 797                  * 11.2.1.6. Let's hope the current solution is adequate enough.
 798                  */
 799
 800                 if (is_after_msecs(fw.wlan.cab_flush_time,
 801                     (CARL9170_TBTT_DELTA))) {
 802                         wlan_cab_flush_queue();
 803                 }
 804         }
 805 #endif /* CONFIG_CARL9170FW_CAB_QUEUE */
 806
 807 #ifdef CONFIG_CARL9170FW_DELAYED_TX
 808         if (fw.wlan.tx_trigger) {
 809                 _wlan_trigger(fw.wlan.tx_trigger);
 810                 fw.wlan.tx_trigger = 0;
 811         }
 812 #endif /* CONFIG_CARL9170FW_DELAYED_TX */
 813
 814         wlan_send_buffered_tx_status();
 815
 816 #ifdef CONFIG_CARL9170FW_HANDLE_BACK_REQ
 817         wlan_send_buffered_ba();
 818 #endif /* CONFIG_CARL9170FW_HANDLE_BACK_REQ */
 819 }
 820
 821 void handle_wlan(void)
 822 {
 823         uint32_t intr;
 824
 825         intr = get(AR9170_MAC_REG_INT_CTRL);
 826         /* ACK Interrupt */
 827         set(AR9170_MAC_REG_INT_CTRL, intr);
 828
 829 #define HANDLER(intr, flag, func)                       \
 830         do {                                            \
 831                 if ((intr & flag) != 0) {               \
 832                         func();                         \
 833                 }                                       \
 834         } while (0)
 835
 836         HANDLER(intr, AR9170_MAC_INT_PRETBTT, handle_pretbtt);
 837
 838         HANDLER(intr, AR9170_MAC_INT_ATIM, handle_atim);
 839
 840         HANDLER(intr, AR9170_MAC_INT_RXC, handle_rx);
 841
 842         HANDLER(intr, (AR9170_MAC_INT_TXC | AR9170_MAC_INT_RETRY_FAIL),
 843                 handle_tx_completion);
 844
 845 #ifdef CONFIG_CARL9170FW_DEBUG
 846         HANDLER(intr, AR9170_MAC_INT_QOS, handle_qos);
 847
 848         HANDLER(intr, AR9170_MAC_INT_RADAR, handle_radar);
 849 #endif /* CONFIG_CARL9170FW_DEBUG */
 850
 851         HANDLER(intr, AR9170_MAC_INT_CFG_BCN, handle_beacon_config);
 852
 853         if (unlikely(intr))
 854                 DBG("Unhandled Interrupt %x\n", (unsigned int) intr);
 855
 856         wlan_janitor();
 857
 858 #undef HANDLER
 859 }
 860
 861 static void wlan_check_hang(void)
 862 {
 863         struct dma_desc *desc;
 864         unsigned int i;
 865
 866         for (i = 0; i < __AR9170_NUM_TX_QUEUES; i++) {
 867                 if (queue_empty(&fw.wlan.tx_queue[i])) {
 868                         /* Nothing to do here... move along */
 869                         continue;
 870                 }
 871
 872                 /* fetch the current DMA queue position */
 873                 desc = get_wlan_txq_addr(i);
 874
 875                 /* Stuck frame detection */
 876                 if (unlikely(desc == fw.wlan.last_tx_desc[i])) {
 877                         fw.wlan.last_tx_desc_num[i]++;
 878
 879                         if (unlikely(fw.wlan.last_tx_desc_num[i] > 6)) {
 880                                 /*
 881                                  * schedule MAC reset (aka OFF/ON => dead)
 882                                  *
 883                                  * This will almost certainly kill
 884                                  * the device for good, but it's the
 885                                  * recommended thing to do...
 886                                  */
 887
 888                                 fw.wlan.mac_reset++;
 889                         }
 890
 891 #ifdef CONFIG_CARL9170FW_DEBUG
 892                         if (unlikely(fw.wlan.last_tx_desc_num[i] > 5)) {
 893                                 /*
 894                                  * Sigh, the queue is almost certainly
 895                                  * dead. Dump the queue content to the
 896                                  * user, maybe we find out why it got
 897                                  * so stuck.
 898                                  */
 899
 900                                 wlan_dump_queue(i);
 901                         }
 902 #endif /* CONFIG_CARL9170FW_DEBUG */
 903
 904                         if (unlikely(fw.wlan.last_tx_desc_num[i] > 3)) {
 905                                 /*
 906                                  * Hrrm, bump the queue a bit.
 907                                  * maybe this will get it going again.
 908                                  */
 909
 910                                 wlan_dma_bump(i);
 911                         }
 912                 } else {
 913                         /* Nothing stuck */
 914                         fw.wlan.last_tx_desc[i] = desc;
 915                         fw.wlan.last_tx_desc_num[i] = 0;
 916                 }
 917         }
 918 }
 919
 920 /*
 921  * NB: Resetting the MAC is a two-edged sword.
 922  * On most occasions, it does what it is supposed to do.
 923  * But there is a chance that this will make it
 924  * even worse and the radio dies silently.
 925  */
 926 static void wlan_mac_reset(void)
 927 {
 928         uint32_t val;
 929         uint32_t agg_wait_counter;
 930         uint32_t agg_density;
 931         uint32_t bcn_start_addr;
 932         uint32_t rctl, rcth;
 933         uint32_t cam_mode;
 934         uint32_t ack_power;
 935         uint32_t rts_cts_tpc;
 936         unsigned int i;
 937
 938 #ifdef CONFIG_CARL9170FW_RADIO_FUNCTIONS
 939         uint32_t rx_BB;
 940 #endif /* CONFIG_CARL9170FW_RADIO_FUNCTIONS */
 941
 942         ERR("MAC RESET");
 943
 944         /* Save aggregation parameters */
 945         agg_wait_counter = get(AR9170_MAC_REG_AMPDU_FACTOR);
 946         agg_density = get(AR9170_MAC_REG_AMPDU_DENSITY);
 947
 948         bcn_start_addr = get(AR9170_MAC_REG_BCN_ADDR);
 949
 950         cam_mode = get(AR9170_MAC_REG_CAM_MODE);
 951         rctl = get(AR9170_MAC_REG_CAM_ROLL_CALL_TBL_L);
 952         rcth = get(AR9170_MAC_REG_CAM_ROLL_CALL_TBL_H);
 953
 954         ack_power = get(AR9170_MAC_REG_ACK_TPC);
 955         rts_cts_tpc = get(AR9170_MAC_REG_RTS_CTS_TPC);
 956
 957 #ifdef CONFIG_CARL9170FW_RADIO_FUNCTIONS
 958         /* 0x1c8960 write only */
 959         rx_BB = get(AR9170_PHY_REG_SWITCH_CHAIN_0);
 960 #endif /* CONFIG_CARL9170FW_RADIO_FUNCTIONS */
 961
 962         /* TX/RX must be stopped by now */
 963         val = get(AR9170_MAC_REG_POWER_STATE_CTRL);
 964
 965         val |= AR9170_MAC_POWER_STATE_CTRL_RESET;
 966
 967         /*
 968          * Manipulate CCA threshold to stop transmission
 969          *
 970          * set(AR9170_PHY_REG_CCA_THRESHOLD, 0x300);
 971          */
 972
 973         /*
 974          * check Rx state in 0(idle) 9(disable)
 975          *
 976          * chState = (get(AR9170_MAC_REG_MISC_684) >> 16) & 0xf;
 977          * while( (chState != 0) && (chState != 9)) {
 978          *      chState = (get(AR9170_MAC_REG_MISC_684) >> 16) & 0xf;
 979          * }
 980          */
 981
 982         set(AR9170_MAC_REG_POWER_STATE_CTRL, val);
 983
 984         delay(2);
 985
 986         /* Restore aggregation parameters */
 987         set(AR9170_MAC_REG_AMPDU_FACTOR, agg_wait_counter);
 988         set(AR9170_MAC_REG_AMPDU_DENSITY, agg_density);
 989
 990         set(AR9170_MAC_REG_BCN_ADDR, bcn_start_addr);
 991         set(AR9170_MAC_REG_CAM_MODE, cam_mode);
 992         set(AR9170_MAC_REG_CAM_ROLL_CALL_TBL_L, rctl);
 993         set(AR9170_MAC_REG_CAM_ROLL_CALL_TBL_H, rcth);
 994
 995         set(AR9170_MAC_REG_RTS_CTS_TPC, rts_cts_tpc);
 996         set(AR9170_MAC_REG_ACK_TPC, ack_power);
 997
 998 #ifdef CONFIG_CARL9170FW_RADIO_FUNCTIONS
 999         set(AR9170_PHY_REG_SWITCH_CHAIN_2, rx_BB);
1000 #endif /* CONFIG_CARL9170FW_RADIO_FUNCTIONS */
1001
1002         /*
1003          * Manipulate CCA threshold to resume transmission
1004          *
1005          * set(AR9170_PHY_REG_CCA_THRESHOLD, 0x0);
1006          */
1007
1008         for (i = 0; i < __AR9170_NUM_TX_QUEUES; i++) {
1009                 DBG("Q:%d l:%d h:%p t:%p\n", i, queue_len(&fw.wlan.tx_queue[i]),
1010                      fw.wlan.tx_queue[i].head, fw.wlan.tx_queue[i].terminator);
1011
1012                 set_wlan_txq_dma_addr(i, (uint32_t) fw.wlan.tx_queue[i].head);
1013
1014                 if (!queue_empty(&fw.wlan.tx_queue[i]))
1015                         wlan_trigger(BIT(i));
1016         }
1017
1018         handle_rx();
1019         set(AR9170_MAC_REG_DMA_RXQ_ADDR, (uint32_t) fw.wlan.rx_queue.head);
1020         wlan_trigger(AR9170_DMA_TRIGGER_RXQ);
1021 }
1022
1023 void __cold wlan_timer(void)
1024 {
1025         unsigned int cached_mac_reset;
1026
1027         cached_mac_reset = fw.wlan.mac_reset;
1028
1029         /* TX Queue Hang check */
1030         wlan_check_hang();
1031
1032         /* RX Overrun check */
1033         wlan_check_rx_overrun();
1034
1035         if (unlikely(fw.wlan.mac_reset >= CARL9170_MAC_RESET_RESET)) {
1036                 wlan_mac_reset();
1037                 fw.wlan.mac_reset = CARL9170_MAC_RESET_OFF;
1038         } else {
1039                 if (fw.wlan.mac_reset && cached_mac_reset == fw.wlan.mac_reset)
1040                         fw.wlan.mac_reset--;
1041         }
1042 }