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 #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         wlan_trigger(BIT(queue));
  46 }
  47
  48 static void wlan_dma_bump(unsigned int qidx)
  49 {
  50         unsigned int offset = qidx;
  51         uint32_t status, trigger;
  52
  53         status = get(AR9170_MAC_REG_DMA_STATUS) >> 12;
  54         trigger = get(AR9170_MAC_REG_DMA_TRIGGER) >> 12;
  55
  56         while (offset != 0) {
  57                 status >>= 4;
  58                 trigger >>= 4;
  59                 offset--;
  60         }
  61
  62         status &= 0xf;
  63         trigger &= 0xf;
  64
  65         if ((trigger == 0xa) && (status == 0x8)) {
  66                 DBG("UNSTUCK");
  67                 wlan_txunstuck(qidx);
  68         } else {
  69                 DBG("UPDATE");
  70                 wlan_txupdate(qidx);
  71         }
  72 }
  73 #endif /* CONFIG_CARL9170FW_DMA_QUEUE_BUMP */
  74
  75 #ifdef CONFIG_CARL9170FW_DEBUG
  76 static void wlan_dump_queue(unsigned int qidx)
  77 {
  78
  79         struct dma_desc *desc;
  80         struct carl9170_tx_superframe *super;
  81         int entries = 0;
  82
  83         __for_each_desc(desc, &fw.wlan.tx_queue[qidx]) {
  84                 super = get_super(desc);
  85                 DBG("%d: %p s:%x c:%x tl:%x ds:%x n:%p l:%p ", entries, desc,
  86                     desc->status, desc->ctrl, desc->totalLen,
  87                     desc->dataSize, desc->nextAddr, desc->lastAddr);
  88
  89                 DBG("c:%x tr:%d ri:%d l:%x m:%x p:%x fc:%x",
  90                     super->s.cookie, super->s.cnt, super->s.rix,
  91                     super->f.hdr.length, super->f.hdr.mac.set,
  92                     (unsigned int) le32_to_cpu(super->f.hdr.phy.set),
  93                     super->f.data.i3e.frame_control);
  94
  95                 entries++;
  96         }
  97
  98         desc = get_wlan_txq_addr(qidx);
  99
 100         DBG("Queue: %d: te:%d td:%d h:%p c:%p t:%p",
 101             qidx, entries, queue_len(&fw.wlan.tx_queue[qidx]),
 102             fw.wlan.tx_queue[qidx].head,
 103             desc, fw.wlan.tx_queue[qidx].terminator);
 104
 105         DBG("HW: t:%x s:%x ac:%x c:%x",
 106             (unsigned int) get(AR9170_MAC_REG_DMA_TRIGGER),
 107             (unsigned int) get(AR9170_MAC_REG_DMA_STATUS),
 108             (unsigned int) get(AR9170_MAC_REG_AMPDU_COUNT),
 109             (unsigned int) get(AR9170_MAC_REG_DMA_TXQX_ADDR_CURR));
 110 }
 111 #endif /* CONFIG_CARL9170FW_DEBUG */
 112
 113 static void wlan_send_buffered_tx_status(void)
 114 {
 115         unsigned int len;
 116
 117         while (fw.wlan.tx_status_pending) {
 118                 len = min((unsigned int)fw.wlan.tx_status_pending,
 119                           CARL9170_RSP_TX_STATUS_NUM);
 120                 len = min(len, CARL9170_TX_STATUS_NUM - fw.wlan.tx_status_head_idx);
 121
 122                 /*
 123                  * rather than memcpy each individual request into a large buffer,
 124                  * we _splice_ them all together.
 125                  *
 126                  * The only downside is however that we have to be careful around
 127                  * the edges of the tx_status_cache.
 128                  *
 129                  * Note:
 130                  * Each tx_status is about 2 bytes. However every command package
 131                  * must have a size which is a multiple of 4.
 132                  */
 133
 134                 send_cmd_to_host((len * sizeof(struct carl9170_tx_status) + 3) & ~3,
 135                                  CARL9170_RSP_TXCOMP, len, (void *)
 136                                  &fw.wlan.tx_status_cache[fw.wlan.tx_status_head_idx]);
 137
 138                 fw.wlan.tx_status_pending -= len;
 139                 fw.wlan.tx_status_head_idx += len;
 140                 fw.wlan.tx_status_head_idx %= CARL9170_TX_STATUS_NUM;
 141         }
 142 }
 143
 144 static struct carl9170_tx_status *wlan_get_tx_status_buffer(void)
 145 {
 146         struct carl9170_tx_status *tmp;
 147
 148         tmp = &fw.wlan.tx_status_cache[fw.wlan.tx_status_tail_idx++];
 149         fw.wlan.tx_status_tail_idx %= CARL9170_TX_STATUS_NUM;
 150
 151         if (fw.wlan.tx_status_pending == CARL9170_TX_STATUS_NUM)
 152                 wlan_send_buffered_tx_status();
 153
 154         fw.wlan.tx_status_pending++;
 155
 156         return tmp;
 157 }
 158
 159 /* generate _aggregated_ tx_status for the host */
 160 static void wlan_tx_complete(struct carl9170_tx_superframe *super,
 161                              bool txs)
 162 {
 163         struct carl9170_tx_status *status;
 164
 165         status = wlan_get_tx_status_buffer();
 166
 167         /*
 168          * The *unique* cookie and AC_ID is used by the driver for
 169          * frame lookup.
 170          */
 171         status->cookie = super->s.cookie;
 172         status->queue = super->s.queue;
 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 /* for all tries */
 216 static void __wlan_tx(struct dma_desc *desc)
 217 {
 218         struct carl9170_tx_superframe *super = get_super(desc);
 219 #ifdef CONFIG_CARL9170FW_NORMAL_TX_RX
 220         unsigned int queue = super->s.queue;
 221 #endif /* CONFIG_CARL9170FW_LOOPBACK */
 222
 223         if (unlikely(super->s.fill_in_tsf)) {
 224                 struct ieee80211_mgmt *mgmt = (void *) &super->f.data.i3e;
 225                 uint32_t *tsf = (uint32_t *) &mgmt->u.probe_resp.timestamp;
 226
 227                 /*
 228                  * Truth be told: this is a hack.
 229                  *
 230                  * The *real* TSF is definitely going to be higher/older.
 231                  * But this hardware emulation code is head and shoulders
 232                  * above anything a driver can possibly do.
 233                  *
 234                  * (even, if it's got an accurate atomic clock source).
 235                  */
 236
 237                 read_tsf(tsf);
 238         }
 239
 240 #if (defined CONFIG_CARL9170FW_LOOPBACK) || (defined CONFIG_CARL9170FW_DISCARD)
 241         wlan_tx_complete(super, true);
 242         unhide_super(desc);
 243 # ifdef CONFIG_CARL9170FW_LOOPBACK
 244         dma_put(&fw.pta.up_queue, desc);
 245         up_trigger();
 246 # elif CONFIG_CARL9170FW_DISCARD
 247         dma_reclaim(&fw.pta.down_queue, desc);
 248         down_trigger();
 249 # endif
 250 #else /* CONFIG_CARL9170FW_LOOPBACK */
 251
 252 # if ((defined CONFIG_CARL9170FW_DEBUG) && (defined CONFIG_CARL9170FW_PSM))
 253         BUG_ON(fw.phy.psm.state != CARL9170_PSM_WAKE);
 254 # endif /* CONFIG_CARL9170FW_DEBUG && CONFIG_CARL9170FW_PSM */
 255
 256         /* insert desc into the right queue */
 257         dma_put(&fw.wlan.tx_queue[queue], desc);
 258         wlan_trigger(BIT(queue));
 259 #endif /* CONFIG_CARL9170FW_LOOPBACK */
 260 }
 261
 262 /* prepares frame for the first transmission */
 263 static void _wlan_tx(struct dma_desc *desc)
 264 {
 265         struct carl9170_tx_superframe *super = get_super(desc);
 266
 267         if (unlikely(super->s.ampdu_commit_density)) {
 268                 set(AR9170_MAC_REG_AMPDU_DENSITY,
 269                     MOD_VAL(AR9170_MAC_AMPDU_DENSITY,
 270                             get(AR9170_MAC_REG_AMPDU_DENSITY),
 271                             super->s.ampdu_density));
 272         }
 273
 274         if (unlikely(super->s.ampdu_commit_factor)) {
 275                 set(AR9170_MAC_REG_AMPDU_FACTOR,
 276                     MOD_VAL(AR9170_MAC_AMPDU_FACTOR,
 277                             get(AR9170_MAC_REG_AMPDU_FACTOR),
 278                             8 << super->s.ampdu_factor));
 279         }
 280
 281         __wlan_tx(desc);
 282 }
 283
 284 /* propagate transmission status back to the driver */
 285 static bool wlan_tx_status(struct dma_queue *queue,
 286                            struct dma_desc *desc)
 287 {
 288         struct ar9170_tx_frame *frame = DESC_PAYLOAD(desc);
 289         struct carl9170_tx_superframe *super = get_super(desc);
 290         struct ieee80211_hdr *hdr = &super->f.data.i3e;
 291         unsigned int qidx = super->s.queue;
 292         bool txfail, success;
 293
 294         success = true;
 295
 296         /* update hangcheck */
 297         fw.wlan.last_tx_desc_num[qidx] = 0;
 298
 299         if (!!(desc->ctrl & AR9170_CTRL_FAIL)) {
 300                 txfail = !!(desc->ctrl & AR9170_CTRL_TXFAIL);
 301
 302                 /* reset retry indicator flags */
 303                 desc->ctrl &= ~(AR9170_CTRL_TXFAIL | AR9170_CTRL_BAFAIL);
 304
 305                 if (wlan_tx_consume_retry(super)) {
 306                         /*
 307                          * retry for simple and aggregated 802.11 frames.
 308                          *
 309                          * Note: We must not mess up the original frame
 310                          * order.
 311                          */
 312
 313                         if (!frame->hdr.mac.ampdu) {
 314                                 /*
 315                                  * 802.11 - 7.1.3.1.5.
 316                                  * set "Retry Field" for consecutive attempts
 317                                  *
 318                                  * Note: For AMPDU see:
 319                                  * 802.11n 9.9.1.6 "Retransmit Procedures"
 320                                  */
 321
 322                                 hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_RETRY);
 323                         }
 324
 325                         if (txfail) {
 326                                 /* Normal TX Failure */
 327
 328                                 /* demise descriptor ownership back to the hardware */
 329                                 dma_rearm(desc);
 330
 331                                 /*
 332                                  * And this will get the queue going again.
 333                                  * To understand why: you have to get the HW
 334                                  * specs... But sadly I never saw them.
 335                                  */
 336                                 wlan_txunstuck(qidx);
 337
 338                                 /* abort cycle - this is necessary due to HW design */
 339                                 return false;
 340                         } else {
 341                                 /* (HT-) BlockACK failure */
 342
 343                                 /*
 344                                  * Unlink the failed attempt and put it into
 345                                  * the retry queue. The caller routine must
 346                                  * be aware of this so the frames don't get lost.
 347                                  */
 348
 349                                 dma_unlink_head(queue);
 350 #ifdef CONFIG_CARL9170FW_DELAYED_TX
 351                                 dma_put(&fw.wlan.tx_retry, desc);
 352 #else
 353                                 __wlan_tx(desc);
 354 #endif /* CONFIG_CARL9170FW_DELAYED_TX */
 355                                 return true;
 356                         }
 357                 } else {
 358                         /* out of frame attempts - discard frame */
 359                         success = false;
 360                 }
 361         }
 362
 363         dma_unlink_head(queue);
 364         if (txfail) {
 365                 /*
 366                  * Issue the queue bump,
 367                  * We need to do this in case this was the frame's last
 368                  * possible retry attempt and it unfortunately: it failed.
 369                  */
 370
 371                 wlan_txunstuck(qidx);
 372         }
 373
 374         unhide_super(desc);
 375
 376 #ifdef CONFIG_CARL9170FW_HANDLE_BACK_REQ
 377         if (unlikely(super == (void *) &dma_mem.reserved.ba)) {
 378                 fw.wlan.ba_desc = desc;
 379                 fw.wlan.ba_desc_available = 1;
 380                 return true;
 381         }
 382 #endif /* CONFIG_CARL9170FW_HANDLE_BACK_REQ */
 383
 384         wlan_tx_complete(super, success);
 385
 386 #ifdef CONFIG_CARL9170FW_CAB_QUEUE
 387         if (unlikely(super->s.cab))
 388                 fw.wlan.cab_queue_len[super->s.vif_id]--;
 389 #endif /* CONFIG_CARL9170FW_CAB_QUEUE */
 390
 391         /* recycle freed descriptors */
 392         dma_reclaim(&fw.pta.down_queue, desc);
 393         down_trigger();
 394         return true;
 395 }
 396
 397 static void handle_tx_completion(void)
 398 {
 399         struct dma_desc *desc;
 400         unsigned int i;
 401
 402         for (i = 0; i < __AR9170_NUM_TX_QUEUES; i++) {
 403                 __while_desc_bits(desc, &fw.wlan.tx_queue[i], AR9170_OWN_BITS_SW) {
 404                         if (!wlan_tx_status(&fw.wlan.tx_queue[i], desc)) {
 405                                 /* termination requested. */
 406                                 break;
 407                         }
 408                 }
 409
 410 #ifdef CONFIG_CARL9170FW_DELAYED_TX
 411                 for_each_desc(desc, &fw.wlan.tx_retry)
 412                         __wlan_tx(desc);
 413
 414                 for_each_desc(desc, &fw.wlan.tx_delay[i])
 415                         _wlan_tx(desc);
 416 #endif /* CONFIG_CARL9170FW_DELAYED_TX */
 417         }
 418 }
 419
 420 void __hot wlan_tx(struct dma_desc *desc)
 421 {
 422         struct carl9170_tx_superframe *super = DESC_PAYLOAD(desc);
 423
 424         /* initialize rate control struct */
 425         super->s.rix = 0;
 426         super->s.cnt = 1;
 427         hide_super(desc);
 428
 429 #ifdef CONFIG_CARL9170FW_DELAYED_TX
 430         if (!queue_empty(&fw.wlan.tx_queue[super->s.queue])) {
 431                 dma_put(&fw.wlan.tx_delay[super->s.queue], desc);
 432                 return;
 433         }
 434 #endif /* CONFIG_CARL9170FW_DELAYED_TX */
 435
 436 #ifdef CONFIG_CARL9170FW_CAB_QUEUE
 437         if (unlikely(super->s.cab)) {
 438                 fw.wlan.cab_queue_len[super->s.vif_id]++;
 439                 dma_put(&fw.wlan.cab_queue[super->s.vif_id], desc);
 440                 return;
 441         }
 442 #endif /* CONFIG_CARL9170FW_CAB_QUEUE */
 443
 444         _wlan_tx(desc);
 445 }
 446
 447 #ifdef CONFIG_CARL9170FW_HANDLE_BACK_REQ
 448 static void wlan_send_buffered_ba(void)
 449 {
 450         struct carl9170_tx_ba_superframe *baf = &dma_mem.reserved.ba.ba;
 451         struct ieee80211_ba *ba = (struct ieee80211_ba *) &baf->f.ba;
 452         struct carl9170_bar_ctx *ctx;
 453
 454         if (likely(fw.wlan.ba_head_idx == fw.wlan.ba_tail_idx))
 455                 return;
 456
 457         /* there's no point to continue when the ba_desc is not available. */
 458         if (!fw.wlan.ba_desc_available)
 459                 return;
 460
 461         ctx = &fw.wlan.ba_cache[fw.wlan.ba_head_idx % CONFIG_CARL9170FW_BACK_REQS_NUM];
 462         fw.wlan.ba_head_idx++;
 463
 464         /* Format BlockAck */
 465         fw.wlan.ba_desc->status = 0;
 466         fw.wlan.ba_desc->ctrl = AR9170_CTRL_FS_BIT | AR9170_CTRL_LS_BIT;
 467         fw.wlan.ba_desc_available = 0;
 468         fw.wlan.ba_desc->nextAddr = fw.wlan.ba_desc->lastAddr =
 469                 fw.wlan.ba_desc;
 470
 471         baf->s.len = fw.wlan.ba_desc->totalLen = fw.wlan.ba_desc->dataSize =
 472                 sizeof(struct carl9170_tx_superdesc) +
 473                 sizeof(struct ar9170_tx_hwdesc) +
 474                 sizeof(struct ieee80211_ba);
 475
 476         baf->s.ri[0].tries = 3;
 477         baf->s.queue = 0;
 478         baf->f.hdr.length = sizeof(struct ieee80211_ba) + FCS_LEN;
 479
 480         /* HW Duration / Backoff */
 481         baf->f.hdr.mac.backoff = 1;
 482         baf->f.hdr.mac.hw_duration = 1;
 483
 484         /* take the TX rate from the RX'd BAR */
 485         baf->f.hdr.phy.set = ctx->phy;
 486         baf->f.hdr.phy.tx_power = 29; /* 14.5 dBm */
 487
 488         /* format outgoing BA */
 489         ba->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL | IEEE80211_STYPE_BACK);
 490         ba->duration = cpu_to_le16(0);
 491         memcpy(ba->ta, ctx->ta, 6);
 492         memcpy(ba->ra, ctx->ra, 6);
 493
 494         /*
 495          * Unfortunately, we cannot look into the hardware's scoreboard.
 496          * Therefore we have to proceed as described in 802.11n 9.10.7.5
 497          * and send a null BlockAck.
 498          */
 499         memset(ba->bitmap, 0x0, sizeof(ba->bitmap));
 500
 501         /*
 502          * NB:
 503          * not entirely sure if this is 100% correct?!
 504          */
 505         ba->control = ctx->control | cpu_to_le16(1);
 506         ba->start_seq_num = ctx->start_seq_num;
 507
 508         wlan_tx(fw.wlan.ba_desc);
 509 }
 510
 511 static struct carl9170_bar_ctx *wlan_get_bar_cache_buffer(void)
 512 {
 513         struct carl9170_bar_ctx *tmp;
 514
 515         /* expire oldest entry, if we ran out of ba_ctx' */
 516         if (fw.wlan.ba_head_idx + CONFIG_CARL9170FW_BACK_REQS_NUM < fw.wlan.ba_tail_idx)
 517                 fw.wlan.ba_head_idx++;
 518
 519         tmp = &fw.wlan.ba_cache[fw.wlan.ba_tail_idx % CONFIG_CARL9170FW_BACK_REQS_NUM];
 520         fw.wlan.ba_tail_idx++;
 521
 522         return tmp;
 523 }
 524
 525 static void handle_bar(struct dma_desc *desc)
 526 {
 527         struct ieee80211_hdr *hdr;
 528         struct ieee80211_bar *bar;
 529         struct carl9170_bar_ctx *ctx;
 530
 531         hdr = ar9170_get_rx_i3e(desc);
 532
 533         /* check if this is a BAR for us */
 534         if (likely(!ieee80211_is_back_req(hdr->frame_control)))
 535                 return ;
 536
 537         if (unlikely(ar9170_get_rx_macstatus_error(desc))) {
 538                 /*
 539                  * This check does a number of things:
 540                  * 1. checks if the frame is in good nick
 541                  * 2. checks if the RA (MAC) matches
 542                  */
 543                 return ;
 544         }
 545
 546         if (unlikely(ar9170_get_rx_mpdu_len(desc) <
 547             sizeof(struct ieee80211_bar))) {
 548                 /*
 549                  * Sneaky, corrupted BARs... but not with us!
 550                  */
 551
 552                 return ;
 553         }
 554
 555         bar = (void *) hdr;
 556
 557         if ((bar->control & cpu_to_le16(IEEE80211_BAR_CTRL_MULTI_TID)) ||
 558             !(bar->control & cpu_to_le16(IEEE80211_BAR_CTRL_CBMTID_COMPRESSED_BA))) {
 559                 /* not implemented yet */
 560
 561                 return ;
 562         }
 563
 564         ctx = wlan_get_bar_cache_buffer();
 565
 566         /* Brilliant! The BAR provides all necessary MACs! */
 567         memcpy(ctx->ra, bar->ta, 6);
 568         memcpy(ctx->ta, bar->ra, 6);
 569
 570         /*
 571          * NB:
 572          * not entirely sure if this is 100% correct to force the
 573          * imm ack bit or not...
 574          */
 575         ctx->control = bar->control | cpu_to_le16(1);
 576         ctx->start_seq_num = bar->start_seq_num;
 577         ctx->phy = ar9170_rx_to_phy(desc);
 578         if (unlikely(!ctx->phy)) {
 579                 /* provide a backup, in case ar9170_rx_to_phy fails */
 580                 ctx->phy = cpu_to_le32(0x2cc301);
 581         }
 582 }
 583 #endif /* CONFIG_CARL9170FW_HANDLE_BACK_REQ */
 584
 585 static void wlan_check_rx_overrun(void)
 586 {
 587         uint32_t overruns, total;
 588
 589         fw.wlan.rx_total += total = get(AR9170_MAC_REG_RX_TOTAL);
 590         fw.wlan.rx_overruns += overruns = get(AR9170_MAC_REG_RX_OVERRUN);
 591         if (unlikely(overruns)) {
 592                 if (overruns == total) {
 593                         DBG("RX Overrun");
 594                         fw.wlan.mac_reset++;
 595                 }
 596
 597                 wlan_trigger(AR9170_DMA_TRIGGER_RXQ);
 598         }
 599 }
 600
 601 static void handle_rx(void)
 602 {
 603         struct dma_desc *desc;
 604
 605         for_each_desc_not_bits(desc, &fw.wlan.rx_queue, AR9170_OWN_BITS_HW) {
 606                 if (unlikely(desc->totalLen < 26 ||
 607                     desc->totalLen > CONFIG_CARL9170FW_RX_FRAME_LEN)) {
 608                         /*
 609                          * This frame is too damaged to do anything
 610                          * useful with it.
 611                          */
 612                         dma_reclaim(&fw.wlan.rx_queue, desc);
 613                         _wlan_trigger(AR9170_DMA_TRIGGER_RXQ);
 614                 } else {
 615 #ifdef CONFIG_CARL9170FW_HANDLE_BACK_REQ
 616                         handle_bar(desc);
 617 #endif /* CONFIG_CARL9170FW_HANDLE_BACK_REQ */
 618
 619                         dma_put(&fw.pta.up_queue, desc);
 620                         up_trigger();
 621                 }
 622         }
 623 }
 624
 625 #ifdef CONFIG_CARL9170FW_CAB_QUEUE
 626 void wlan_cab_flush_queue(const unsigned int vif)
 627 {
 628         struct dma_queue *cab_queue = &fw.wlan.cab_queue[vif];
 629         struct dma_desc *desc;
 630
 631         /* move queued frames into the main tx queues */
 632         for_each_desc(desc, cab_queue) {
 633                 struct carl9170_tx_superframe *super = get_super(desc);
 634                 if (!queue_empty(cab_queue)) {
 635                         /*
 636                          * Set MOREDATA flag for all,
 637                          * but the last queued frame.
 638                          * see: 802.11-2007 11.2.1.5 f)
 639                          *
 640                          * This is actually the reason to why
 641                          * we need to prevent the reentry.
 642                          */
 643
 644                         super->f.data.i3e.frame_control |=
 645                                 cpu_to_le16(IEEE80211_FCTL_MOREDATA);
 646                 } else {
 647                         super->f.data.i3e.frame_control &=
 648                                 cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
 649                 }
 650
 651                 /* ready to roll! */
 652                 _wlan_tx(desc);
 653         }
 654 }
 655
 656 static uint8_t *beacon_find_ie(uint8_t ie, void *addr,
 657                                const unsigned int len)
 658 {
 659         struct ieee80211_mgmt *mgmt = addr;
 660         uint8_t *pos, *end;
 661
 662         pos = mgmt->u.beacon.variable;
 663         end = (uint8_t *) ((unsigned long)mgmt + (len - FCS_LEN));
 664         while (pos < end) {
 665                 if (pos + 2 + pos[1] > end)
 666                         return NULL;
 667
 668                 if (pos[0] == ie)
 669                         return pos;
 670
 671                 pos += pos[1] + 2;
 672         }
 673
 674         return NULL;
 675 }
 676
 677 void wlan_cab_modify_dtim_beacon(const unsigned int vif,
 678         const unsigned int addr, const unsigned int len)
 679 {
 680         uint8_t *_ie;
 681         struct ieee80211_tim_ie *ie;
 682
 683         _ie = beacon_find_ie(WLAN_EID_TIM, (void *)addr, len);
 684         if (likely(_ie)) {
 685                 ie = (struct ieee80211_tim_ie *) &_ie[2];
 686
 687                 if (!queue_empty(&fw.wlan.cab_queue[vif]) && (ie->dtim_count == 0)) {
 688                         /* schedule DTIM transfer */
 689                         fw.wlan.cab_flush_trigger[vif] = CARL9170_CAB_TRIGGER_ARMED;
 690                 } else if ((fw.wlan.cab_queue_len[vif] == 0) && (fw.wlan.cab_flush_trigger[vif])) {
 691                         /* undo all chances to the beacon structure */
 692                         ie->bitmap_ctrl &= ~0x1;
 693                         fw.wlan.cab_flush_trigger[vif] = CARL9170_CAB_TRIGGER_EMPTY;
 694                 }
 695
 696                 /* Triggered by CARL9170_CAB_TRIGGER_ARMED || CARL9170_CAB_TRIGGER_DEFER */
 697                 if (fw.wlan.cab_flush_trigger[vif]) {
 698                         /* Set the almighty Multicast Traffic Indication Bit. */
 699                         ie->bitmap_ctrl |= 0x1;
 700                 }
 701         }
 702 }
 703 #endif /* CONFIG_CARL9170FW_CAB_QUEUE */
 704
 705 static void handle_beacon_config(void)
 706 {
 707         uint32_t bcn_count;
 708
 709         bcn_count = get(AR9170_MAC_REG_BCN_COUNT);
 710         send_cmd_to_host(4, CARL9170_RSP_BEACON_CONFIG, 0x00,
 711                          (uint8_t *) &bcn_count);
 712
 713         set(AR9170_MAC_REG_BCN_CTRL, AR9170_BCN_CTRL_READY);
 714 }
 715
 716 static void handle_pretbtt(void)
 717 {
 718 #ifdef CONFIG_CARL9170FW_CAB_QUEUE
 719         fw.wlan.cab_flush_time = get_clock_counter();
 720 #endif /* CONFIG_CARL9170FW_CAB_QUEUE */
 721
 722 #ifdef CONFIG_CARL9170FW_PSM
 723         rf_psm();
 724
 725         send_cmd_to_host(4, CARL9170_RSP_PRETBTT, 0x00,
 726                          (uint8_t *) &fw.phy.psm.state);
 727 #else
 728         send_cmd_to_host(0, CARL9170_RSP_PRETBTT, 0x00, NULL);
 729 #endif /* CONFIG_CARL9170FW_PSM */
 730 }
 731
 732 static void handle_atim(void)
 733 {
 734         send_cmd_to_host(0, CARL9170_RSP_ATIM, 0x00, NULL);
 735 }
 736
 737 #ifdef CONFIG_CARL9170FW_DEBUG
 738 static void handle_qos(void)
 739 {
 740         /*
 741          * What is the QoS Bit used for?
 742          * Is it only an indicator for TXOP & Burst, or
 743          * should we do something here?
 744          */
 745 }
 746
 747 static void handle_radar(void)
 748 {
 749         send_cmd_to_host(0, CARL9170_RSP_RADAR, 0x00, NULL);
 750 }
 751 #endif /* CONFIG_CARL9170FW_DEBUG */
 752
 753 static void wlan_janitor(void)
 754 {
 755 #ifdef CONFIG_CARL9170FW_CAB_QUEUE
 756         unsigned int i;
 757
 758         for (i = 0; i < CARL9170_INTF_NUM; i++) {
 759                 if (unlikely(fw.wlan.cab_flush_trigger[i] == CARL9170_CAB_TRIGGER_ARMED)) {
 760                         /*
 761                          * This is hardcoded into carl9170usb driver.
 762                          *
 763                          * The driver must set the PRETBTT event to beacon_interval -
 764                          * CARL9170_PRETBTT_KUS (usually 6) Kus.
 765                          *
 766                          * But still, we can only do so much about 802.11-2007 9.3.2.1 &
 767                          * 11.2.1.6. Let's hope the current solution is adequate enough.
 768                          */
 769
 770                         if (is_after_msecs(fw.wlan.cab_flush_time, (CARL9170_TBTT_DELTA))) {
 771                                 wlan_cab_flush_queue(i);
 772
 773                                 /*
 774                                  * This prevents the code from sending new BC/MC frames
 775                                  * which were queued after the previous buffered traffic
 776                                  * has been sent out... They will have to wait until the
 777                                  * next DTIM beacon comes along.
 778                                  */
 779                                 fw.wlan.cab_flush_trigger[i] = CARL9170_CAB_TRIGGER_DEFER;
 780                         }
 781                 }
 782
 783         }
 784 #endif /* CONFIG_CARL9170FW_CAB_QUEUE */
 785
 786 #ifdef CONFIG_CARL9170FW_DELAYED_TX
 787         if (fw.wlan.tx_trigger) {
 788                 _wlan_trigger(fw.wlan.tx_trigger);
 789                 fw.wlan.tx_trigger = 0;
 790         }
 791 #endif /* CONFIG_CARL9170FW_DELAYED_TX */
 792
 793         wlan_send_buffered_tx_status();
 794
 795 #ifdef CONFIG_CARL9170FW_HANDLE_BACK_REQ
 796         wlan_send_buffered_ba();
 797 #endif /* CONFIG_CARL9170FW_HANDLE_BACK_REQ */
 798 }
 799
 800 void handle_wlan(void)
 801 {
 802         uint32_t intr;
 803
 804         intr = get(AR9170_MAC_REG_INT_CTRL);
 805         /* ACK Interrupt */
 806         set(AR9170_MAC_REG_INT_CTRL, intr);
 807
 808 #define HANDLER(intr, flag, func)                       \
 809         do {                                            \
 810                 if ((intr & flag) != 0) {               \
 811                         func();                         \
 812                 }                                       \
 813         } while (0)
 814
 815         intr |= fw.wlan.soft_int;
 816         fw.wlan.soft_int = 0;
 817
 818         HANDLER(intr, AR9170_MAC_INT_PRETBTT, handle_pretbtt);
 819
 820         HANDLER(intr, AR9170_MAC_INT_ATIM, handle_atim);
 821
 822         HANDLER(intr, AR9170_MAC_INT_RXC, handle_rx);
 823
 824         HANDLER(intr, (AR9170_MAC_INT_TXC | AR9170_MAC_INT_RETRY_FAIL),
 825                 handle_tx_completion);
 826
 827 #ifdef CONFIG_CARL9170FW_DEBUG
 828         HANDLER(intr, AR9170_MAC_INT_QOS, handle_qos);
 829
 830         HANDLER(intr, AR9170_MAC_INT_RADAR, handle_radar);
 831 #endif /* CONFIG_CARL9170FW_DEBUG */
 832
 833         HANDLER(intr, AR9170_MAC_INT_CFG_BCN, handle_beacon_config);
 834
 835         if (unlikely(intr))
 836                 DBG("Unhandled Interrupt %x\n", (unsigned int) intr);
 837
 838         wlan_janitor();
 839
 840 #undef HANDLER
 841 }
 842
 843 static void wlan_check_hang(void)
 844 {
 845         struct dma_desc *desc;
 846         unsigned int i;
 847
 848         for (i = 0; i < __AR9170_NUM_TX_QUEUES; i++) {
 849                 if (queue_empty(&fw.wlan.tx_queue[i])) {
 850                         /* Nothing to do here... move along */
 851                         continue;
 852                 }
 853
 854                 /* fetch the current DMA queue position */
 855                 desc = get_wlan_txq_addr(i);
 856
 857                 /* Stuck frame detection */
 858                 if (unlikely(desc == fw.wlan.last_tx_desc[i])) {
 859                         fw.wlan.last_tx_desc_num[i]++;
 860
 861                         if (unlikely(fw.wlan.last_tx_desc_num[i] > 6)) {
 862                                 /*
 863                                  * schedule MAC reset (aka OFF/ON => dead)
 864                                  *
 865                                  * This will almost certainly kill
 866                                  * the device for good, but it's the
 867                                  * recommended thing to do...
 868                                  */
 869
 870                                 fw.wlan.mac_reset++;
 871                         }
 872
 873 #ifdef CONFIG_CARL9170FW_DEBUG
 874                         if (unlikely(fw.wlan.last_tx_desc_num[i] > 5)) {
 875                                 /*
 876                                  * Sigh, the queue is almost certainly
 877                                  * dead. Dump the queue content to the
 878                                  * user, maybe we find out why it got
 879                                  * so stuck.
 880                                  */
 881
 882                                 wlan_dump_queue(i);
 883                         }
 884 #endif /* CONFIG_CARL9170FW_DEBUG */
 885
 886 #ifdef CONFIG_CARL9170FW_DMA_QUEUE_BUMP
 887                         if (unlikely(fw.wlan.last_tx_desc_num[i] > 3)) {
 888                                 /*
 889                                  * Hrrm, bump the queue a bit.
 890                                  * maybe this will get it going again.
 891                                  */
 892
 893                                 wlan_dma_bump(i);
 894                         }
 895 #endif /* CONFIG_CARL9170FW_DMA_QUEUE_BUMP */
 896                 } else {
 897                         /* Nothing stuck */
 898                         fw.wlan.last_tx_desc[i] = desc;
 899                         fw.wlan.last_tx_desc_num[i] = 0;
 900                 }
 901         }
 902 }
 903
 904 #ifdef CONFIG_CARL9170FW_FW_MAC_RESET
 905 /*
 906  * NB: Resetting the MAC is a two-edged sword.
 907  * On most occasions, it does what it is supposed to do.
 908  * But there is a chance that this will make it
 909  * even worse and the radio dies silently.
 910  */
 911 static void wlan_mac_reset(void)
 912 {
 913         uint32_t val;
 914         uint32_t agg_wait_counter;
 915         uint32_t agg_density;
 916         uint32_t bcn_start_addr;
 917         uint32_t rctl, rcth;
 918         uint32_t cam_mode;
 919         uint32_t ack_power;
 920         uint32_t rts_cts_tpc;
 921         uint32_t rts_cts_rate;
 922         unsigned int i;
 923
 924 #ifdef CONFIG_CARL9170FW_RADIO_FUNCTIONS
 925         uint32_t rx_BB;
 926 #endif /* CONFIG_CARL9170FW_RADIO_FUNCTIONS */
 927
 928         INFO("MAC RESET");
 929
 930         /* Save aggregation parameters */
 931         agg_wait_counter = get(AR9170_MAC_REG_AMPDU_FACTOR);
 932         agg_density = get(AR9170_MAC_REG_AMPDU_DENSITY);
 933
 934         bcn_start_addr = get(AR9170_MAC_REG_BCN_ADDR);
 935
 936         cam_mode = get(AR9170_MAC_REG_CAM_MODE);
 937         rctl = get(AR9170_MAC_REG_CAM_ROLL_CALL_TBL_L);
 938         rcth = get(AR9170_MAC_REG_CAM_ROLL_CALL_TBL_H);
 939
 940         ack_power = get(AR9170_MAC_REG_ACK_TPC);
 941         rts_cts_tpc = get(AR9170_MAC_REG_RTS_CTS_TPC);
 942         rts_cts_rate = get(AR9170_MAC_REG_RTS_CTS_RATE);
 943
 944 #ifdef CONFIG_CARL9170FW_RADIO_FUNCTIONS
 945         /* 0x1c8960 write only */
 946         rx_BB = get(AR9170_PHY_REG_SWITCH_CHAIN_0);
 947 #endif /* CONFIG_CARL9170FW_RADIO_FUNCTIONS */
 948
 949         /* TX/RX must be stopped by now */
 950         val = get(AR9170_MAC_REG_POWER_STATE_CTRL);
 951
 952         val |= AR9170_MAC_POWER_STATE_CTRL_RESET;
 953
 954         /*
 955          * Manipulate CCA threshold to stop transmission
 956          *
 957          * set(AR9170_PHY_REG_CCA_THRESHOLD, 0x300);
 958          */
 959
 960         /*
 961          * check Rx state in 0(idle) 9(disable)
 962          *
 963          * chState = (get(AR9170_MAC_REG_MISC_684) >> 16) & 0xf;
 964          * while( (chState != 0) && (chState != 9)) {
 965          *      chState = (get(AR9170_MAC_REG_MISC_684) >> 16) & 0xf;
 966          * }
 967          */
 968
 969         set(AR9170_MAC_REG_POWER_STATE_CTRL, val);
 970
 971         delay(2);
 972
 973         /* Restore aggregation parameters */
 974         set(AR9170_MAC_REG_AMPDU_FACTOR, agg_wait_counter);
 975         set(AR9170_MAC_REG_AMPDU_DENSITY, agg_density);
 976
 977         set(AR9170_MAC_REG_BCN_ADDR, bcn_start_addr);
 978         set(AR9170_MAC_REG_CAM_MODE, cam_mode);
 979         set(AR9170_MAC_REG_CAM_ROLL_CALL_TBL_L, rctl);
 980         set(AR9170_MAC_REG_CAM_ROLL_CALL_TBL_H, rcth);
 981
 982         set(AR9170_MAC_REG_RTS_CTS_TPC, rts_cts_tpc);
 983         set(AR9170_MAC_REG_ACK_TPC, ack_power);
 984         set(AR9170_MAC_REG_RTS_CTS_RATE, rts_cts_rate);
 985
 986 #ifdef CONFIG_CARL9170FW_RADIO_FUNCTIONS
 987         set(AR9170_PHY_REG_SWITCH_CHAIN_2, rx_BB);
 988 #endif /* CONFIG_CARL9170FW_RADIO_FUNCTIONS */
 989
 990         /*
 991          * Manipulate CCA threshold to resume transmission
 992          *
 993          * set(AR9170_PHY_REG_CCA_THRESHOLD, 0x0);
 994          */
 995
 996         /* Reinitialize all WLAN TX DMA queues. */
 997         for (i = 0; i < __AR9170_NUM_TX_QUEUES; i++) {
 998                 struct dma_desc *iter;
 999
1000                 __for_each_desc_bits(iter, &fw.wlan.tx_queue[i], AR9170_OWN_BITS_SW);
1001
1002                 set_wlan_txq_dma_addr(i, (uint32_t) iter);
1003                 if (!is_terminator(&fw.wlan.tx_queue[i], iter))
1004                         wlan_trigger(BIT(i));
1005
1006                 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]),
1007                      fw.wlan.tx_queue[i].head, fw.wlan.tx_queue[i].terminator,
1008                      get_wlan_txq_addr(i), iter, iter->ctrl, iter->status);
1009         }
1010
1011         fw.wlan.soft_int |= AR9170_MAC_INT_RXC | AR9170_MAC_INT_TXC |
1012                             AR9170_MAC_INT_RETRY_FAIL;
1013
1014         set(AR9170_MAC_REG_DMA_RXQ_ADDR, (uint32_t) fw.wlan.rx_queue.head);
1015         wlan_trigger(AR9170_DMA_TRIGGER_RXQ);
1016 }
1017 #else
1018 static void wlan_mac_reset(void)
1019 {
1020         /* The driver takes care of reinitializing the device */
1021         BUG("MAC RESET");
1022 }
1023 #endif /* CONFIG_CARL9170FW_FW_MAC_RESET */
1024
1025 void __cold wlan_timer(void)
1026 {
1027         unsigned int cached_mac_reset;
1028
1029         cached_mac_reset = fw.wlan.mac_reset;
1030
1031         /* TX Queue Hang check */
1032         wlan_check_hang();
1033
1034         /* RX Overrun check */
1035         wlan_check_rx_overrun();
1036
1037         if (unlikely(fw.wlan.mac_reset >= CARL9170_MAC_RESET_RESET)) {
1038                 wlan_mac_reset();
1039                 fw.wlan.mac_reset = CARL9170_MAC_RESET_OFF;
1040         } else {
1041                 if (fw.wlan.mac_reset && cached_mac_reset == fw.wlan.mac_reset)
1042                         fw.wlan.mac_reset--;
1043         }
1044 }