drivers/net/wireless/wl12xx/tx.c

   1 /*
   2  * This file is part of wl1271
   3  *
   4  * Copyright (C) 2009 Nokia Corporation
   5  *
   6  * Contact: Luciano Coelho <luciano.coelho@nokia.com>
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License
  10  * version 2 as published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
  20  * 02110-1301 USA
  21  *
  22  */
  23
  24 #include <linux/kernel.h>
  25 #include <linux/module.h>
  26 #include <linux/etherdevice.h>
  27
  28 #include "wl12xx.h"
  29 #include "io.h"
  30 #include "reg.h"
  31 #include "ps.h"
  32 #include "tx.h"
  33
  34 static int wl1271_set_default_wep_key(struct wl1271 *wl, u8 id)
  35 {
  36         int ret;
  37         bool is_ap = (wl->bss_type == BSS_TYPE_AP_BSS);
  38
  39         if (is_ap)
  40                 ret = wl1271_cmd_set_ap_default_wep_key(wl, id);
  41         else
  42                 ret = wl1271_cmd_set_sta_default_wep_key(wl, id);
  43
  44         if (ret < 0)
  45                 return ret;
  46
  47         wl1271_debug(DEBUG_CRYPT, "default wep key idx: %d", (int)id);
  48         return 0;
  49 }
  50
  51 static int wl1271_alloc_tx_id(struct wl1271 *wl, struct sk_buff *skb)
  52 {
  53         int id;
  54
  55         id = find_first_zero_bit(wl->tx_frames_map, ACX_TX_DESCRIPTORS);
  56         if (id >= ACX_TX_DESCRIPTORS)
  57                 return -EBUSY;
  58
  59         __set_bit(id, wl->tx_frames_map);
  60         wl->tx_frames[id] = skb;
  61         wl->tx_frames_cnt++;
  62         return id;
  63 }
  64
  65 static void wl1271_free_tx_id(struct wl1271 *wl, int id)
  66 {
  67         if (__test_and_clear_bit(id, wl->tx_frames_map)) {
  68                 if (unlikely(wl->tx_frames_cnt == ACX_TX_DESCRIPTORS))
  69                         clear_bit(WL1271_FLAG_FW_TX_BUSY, &wl->flags);
  70
  71                 wl->tx_frames[id] = NULL;
  72                 wl->tx_frames_cnt--;
  73         }
  74 }
  75
  76 static int wl1271_tx_update_filters(struct wl1271 *wl,
  77                                                  struct sk_buff *skb)
  78 {
  79         struct ieee80211_hdr *hdr;
  80
  81         hdr = (struct ieee80211_hdr *)(skb->data +
  82                                        sizeof(struct wl1271_tx_hw_descr));
  83
  84         /*
  85          * stop bssid-based filtering before transmitting authentication
  86          * requests. this way the hw will never drop authentication
  87          * responses coming from BSSIDs it isn't familiar with (e.g. on
  88          * roaming)
  89          */
  90         if (!ieee80211_is_auth(hdr->frame_control))
  91                 return 0;
  92
  93         wl1271_configure_filters(wl, FIF_OTHER_BSS);
  94
  95         return wl1271_acx_rx_config(wl, wl->rx_config, wl->rx_filter);
  96 }
  97
  98 static void wl1271_tx_ap_update_inconnection_sta(struct wl1271 *wl,
  99                                                  struct sk_buff *skb)
 100 {
 101         struct ieee80211_hdr *hdr;
 102
 103         /*
 104          * add the station to the known list before transmitting the
 105          * authentication response. this way it won't get de-authed by FW
 106          * when transmitting too soon.
 107          */
 108         hdr = (struct ieee80211_hdr *)(skb->data +
 109                                        sizeof(struct wl1271_tx_hw_descr));
 110         if (ieee80211_is_auth(hdr->frame_control))
 111                 wl1271_acx_set_inconnection_sta(wl, hdr->addr1);
 112 }
 113
 114 static void wl1271_tx_regulate_link(struct wl1271 *wl, u8 hlid)
 115 {
 116         bool fw_ps;
 117         u8 tx_blks;
 118
 119         /* only regulate station links */
 120         if (hlid < WL1271_AP_STA_HLID_START)
 121                 return;
 122
 123         fw_ps = test_bit(hlid, (unsigned long *)&wl->ap_fw_ps_map);
 124         tx_blks = wl->links[hlid].allocated_blks;
 125
 126         /*
 127          * if in FW PS and there is enough data in FW we can put the link
 128          * into high-level PS and clean out its TX queues.
 129          */
 130         if (fw_ps && tx_blks >= WL1271_PS_STA_MAX_BLOCKS)
 131                 wl1271_ps_link_start(wl, hlid, true);
 132 }
 133
 134 u8 wl1271_tx_get_hlid(struct sk_buff *skb)
 135 {
 136         struct ieee80211_tx_info *control = IEEE80211_SKB_CB(skb);
 137
 138         if (control->control.sta) {
 139                 struct wl1271_station *wl_sta;
 140
 141                 wl_sta = (struct wl1271_station *)
 142                                 control->control.sta->drv_priv;
 143                 return wl_sta->hlid;
 144         } else {
 145                 struct ieee80211_hdr *hdr;
 146
 147                 hdr = (struct ieee80211_hdr *)skb->data;
 148                 if (ieee80211_is_mgmt(hdr->frame_control))
 149                         return WL1271_AP_GLOBAL_HLID;
 150                 else
 151                         return WL1271_AP_BROADCAST_HLID;
 152         }
 153 }
 154
 155 static unsigned int wl12xx_calc_packet_alignment(struct wl1271 *wl,
 156                                                 unsigned int packet_length)
 157 {
 158         if (wl->quirks & WL12XX_QUIRK_BLOCKSIZE_ALIGNMENT)
 159                 return ALIGN(packet_length, WL12XX_BUS_BLOCK_SIZE);
 160         else
 161                 return ALIGN(packet_length, WL1271_TX_ALIGN_TO);
 162 }
 163
 164 static int wl1271_tx_allocate(struct wl1271 *wl, struct sk_buff *skb, u32 extra,
 165                                 u32 buf_offset, u8 hlid)
 166 {
 167         struct wl1271_tx_hw_descr *desc;
 168         u32 total_len = skb->len + sizeof(struct wl1271_tx_hw_descr) + extra;
 169         u32 len;
 170         u32 total_blocks;
 171         int id, ret = -EBUSY, ac;
 172         u32 spare_blocks;
 173
 174         if (unlikely(wl->quirks & WL12XX_QUIRK_USE_2_SPARE_BLOCKS))
 175                 spare_blocks = 2;
 176         else
 177                 spare_blocks = 1;
 178
 179         if (buf_offset + total_len > WL1271_AGGR_BUFFER_SIZE)
 180                 return -EAGAIN;
 181
 182         /* allocate free identifier for the packet */
 183         id = wl1271_alloc_tx_id(wl, skb);
 184         if (id < 0)
 185                 return id;
 186
 187         /* approximate the number of blocks required for this packet
 188            in the firmware */
 189         len = wl12xx_calc_packet_alignment(wl, total_len);
 190
 191         total_blocks = (len + TX_HW_BLOCK_SIZE - 1) / TX_HW_BLOCK_SIZE +
 192                 spare_blocks;
 193
 194         if (total_blocks <= wl->tx_blocks_available) {
 195                 desc = (struct wl1271_tx_hw_descr *)skb_push(
 196                         skb, total_len - skb->len);
 197
 198                 /* HW descriptor fields change between wl127x and wl128x */
 199                 if (wl->chip.id == CHIP_ID_1283_PG20) {
 200                         desc->wl128x_mem.total_mem_blocks = total_blocks;
 201                 } else {
 202                         desc->wl127x_mem.extra_blocks = spare_blocks;
 203                         desc->wl127x_mem.total_mem_blocks = total_blocks;
 204                 }
 205
 206                 desc->id = id;
 207
 208                 wl->tx_blocks_available -= total_blocks;
 209
 210                 ac = wl1271_tx_get_queue(skb_get_queue_mapping(skb));
 211                 wl->tx_allocated_blocks[ac] += total_blocks;
 212
 213                 if (wl->bss_type == BSS_TYPE_AP_BSS)
 214                         wl->links[hlid].allocated_blks += total_blocks;
 215
 216                 ret = 0;
 217
 218                 wl1271_debug(DEBUG_TX,
 219                              "tx_allocate: size: %d, blocks: %d, id: %d",
 220                              total_len, total_blocks, id);
 221         } else {
 222                 wl1271_free_tx_id(wl, id);
 223         }
 224
 225         return ret;
 226 }
 227
 228 static bool wl12xx_is_dummy_packet(struct wl1271 *wl, struct sk_buff *skb)
 229 {
 230         return wl->dummy_packet == skb;
 231 }
 232
 233 static void wl1271_tx_fill_hdr(struct wl1271 *wl, struct sk_buff *skb,
 234                               u32 extra, struct ieee80211_tx_info *control,
 235                               u8 hlid)
 236 {
 237         struct timespec ts;
 238         struct wl1271_tx_hw_descr *desc;
 239         int aligned_len, ac, rate_idx;
 240         s64 hosttime;
 241         u16 tx_attr;
 242
 243         desc = (struct wl1271_tx_hw_descr *) skb->data;
 244
 245         /* relocate space for security header */
 246         if (extra) {
 247                 void *framestart = skb->data + sizeof(*desc);
 248                 u16 fc = *(u16 *)(framestart + extra);
 249                 int hdrlen = ieee80211_hdrlen(cpu_to_le16(fc));
 250                 memmove(framestart, framestart + extra, hdrlen);
 251         }
 252
 253         /* configure packet life time */
 254         getnstimeofday(&ts);
 255         hosttime = (timespec_to_ns(&ts) >> 10);
 256         desc->start_time = cpu_to_le32(hosttime - wl->time_offset);
 257
 258         if (wl->bss_type != BSS_TYPE_AP_BSS)
 259                 desc->life_time = cpu_to_le16(TX_HW_MGMT_PKT_LIFETIME_TU);
 260         else
 261                 desc->life_time = cpu_to_le16(TX_HW_AP_MODE_PKT_LIFETIME_TU);
 262
 263         /* queue */
 264         ac = wl1271_tx_get_queue(skb_get_queue_mapping(skb));
 265         desc->tid = skb->priority;
 266
 267         if (wl12xx_is_dummy_packet(wl, skb)) {
 268                 /*
 269                  * FW expects the dummy packet to have an invalid session id -
 270                  * any session id that is different than the one set in the join
 271                  */
 272                 tx_attr = ((~wl->session_counter) <<
 273                            TX_HW_ATTR_OFST_SESSION_COUNTER) &
 274                            TX_HW_ATTR_SESSION_COUNTER;
 275
 276                 tx_attr |= TX_HW_ATTR_TX_DUMMY_REQ;
 277         } else {
 278                 /* configure the tx attributes */
 279                 tx_attr =
 280                         wl->session_counter << TX_HW_ATTR_OFST_SESSION_COUNTER;
 281         }
 282
 283         if (wl->bss_type != BSS_TYPE_AP_BSS) {
 284                 desc->aid = hlid;
 285
 286                 /* if the packets are destined for AP (have a STA entry)
 287                    send them with AP rate policies, otherwise use default
 288                    basic rates */
 289                 if (control->control.sta)
 290                         rate_idx = ACX_TX_AP_FULL_RATE;
 291                 else
 292                         rate_idx = ACX_TX_BASIC_RATE;
 293         } else {
 294                 desc->hlid = hlid;
 295                 switch (hlid) {
 296                 case WL1271_AP_GLOBAL_HLID:
 297                         rate_idx = ACX_TX_AP_MODE_MGMT_RATE;
 298                         break;
 299                 case WL1271_AP_BROADCAST_HLID:
 300                         rate_idx = ACX_TX_AP_MODE_BCST_RATE;
 301                         break;
 302                 default:
 303                         rate_idx = ac;
 304                         break;
 305                 }
 306         }
 307
 308         tx_attr |= rate_idx << TX_HW_ATTR_OFST_RATE_POLICY;
 309         desc->reserved = 0;
 310
 311         aligned_len = wl12xx_calc_packet_alignment(wl, skb->len);
 312
 313         if (wl->chip.id == CHIP_ID_1283_PG20) {
 314                 desc->wl128x_mem.extra_bytes = aligned_len - skb->len;
 315                 desc->length = cpu_to_le16(aligned_len >> 2);
 316
 317                 wl1271_debug(DEBUG_TX, "tx_fill_hdr: hlid: %d "
 318                              "tx_attr: 0x%x len: %d life: %d mem: %d",
 319                              desc->hlid, tx_attr,
 320                              le16_to_cpu(desc->length),
 321                              le16_to_cpu(desc->life_time),
 322                              desc->wl128x_mem.total_mem_blocks);
 323         } else {
 324                 int pad;
 325
 326                 /* Store the aligned length in terms of words */
 327                 desc->length = cpu_to_le16(aligned_len >> 2);
 328
 329                 /* calculate number of padding bytes */
 330                 pad = aligned_len - skb->len;
 331                 tx_attr |= pad << TX_HW_ATTR_OFST_LAST_WORD_PAD;
 332
 333                 wl1271_debug(DEBUG_TX, "tx_fill_hdr: pad: %d hlid: %d "
 334                              "tx_attr: 0x%x len: %d life: %d mem: %d", pad,
 335                              desc->hlid, tx_attr,
 336                              le16_to_cpu(desc->length),
 337                              le16_to_cpu(desc->life_time),
 338                              desc->wl127x_mem.total_mem_blocks);
 339         }
 340
 341         desc->tx_attr = cpu_to_le16(tx_attr);
 342 }
 343
 344 /* caller must hold wl->mutex */
 345 static int wl1271_prepare_tx_frame(struct wl1271 *wl, struct sk_buff *skb,
 346                                                         u32 buf_offset)
 347 {
 348         struct ieee80211_tx_info *info;
 349         u32 extra = 0;
 350         int ret = 0;
 351         u32 total_len;
 352         u8 hlid;
 353
 354         if (!skb)
 355                 return -EINVAL;
 356
 357         info = IEEE80211_SKB_CB(skb);
 358
 359         if (info->control.hw_key &&
 360             info->control.hw_key->cipher == WLAN_CIPHER_SUITE_TKIP)
 361                 extra = WL1271_TKIP_IV_SPACE;
 362
 363         if (info->control.hw_key) {
 364                 bool is_wep;
 365                 u8 idx = info->control.hw_key->hw_key_idx;
 366                 u32 cipher = info->control.hw_key->cipher;
 367
 368                 is_wep = (cipher == WLAN_CIPHER_SUITE_WEP40) ||
 369                          (cipher == WLAN_CIPHER_SUITE_WEP104);
 370
 371                 if (unlikely(is_wep && wl->default_key != idx)) {
 372                         ret = wl1271_set_default_wep_key(wl, idx);
 373                         if (ret < 0)
 374                                 return ret;
 375                         wl->default_key = idx;
 376                 }
 377         }
 378
 379         if (wl->bss_type == BSS_TYPE_AP_BSS)
 380                 hlid = wl1271_tx_get_hlid(skb);
 381         else
 382                 hlid = TX_HW_DEFAULT_AID;
 383
 384         ret = wl1271_tx_allocate(wl, skb, extra, buf_offset, hlid);
 385         if (ret < 0)
 386                 return ret;
 387
 388         wl1271_tx_fill_hdr(wl, skb, extra, info, hlid);
 389
 390         if (wl->bss_type == BSS_TYPE_AP_BSS) {
 391                 wl1271_tx_ap_update_inconnection_sta(wl, skb);
 392                 wl1271_tx_regulate_link(wl, hlid);
 393         } else {
 394                 wl1271_tx_update_filters(wl, skb);
 395         }
 396
 397         /*
 398          * The length of each packet is stored in terms of
 399          * words. Thus, we must pad the skb data to make sure its
 400          * length is aligned.  The number of padding bytes is computed
 401          * and set in wl1271_tx_fill_hdr.
 402          * In special cases, we want to align to a specific block size
 403          * (eg. for wl128x with SDIO we align to 256).
 404          */
 405         total_len = wl12xx_calc_packet_alignment(wl, skb->len);
 406
 407         memcpy(wl->aggr_buf + buf_offset, skb->data, skb->len);
 408         memset(wl->aggr_buf + buf_offset + skb->len, 0, total_len - skb->len);
 409
 410         /* Revert side effects in the dummy packet skb, so it can be reused */
 411         if (wl12xx_is_dummy_packet(wl, skb))
 412                 skb_pull(skb, sizeof(struct wl1271_tx_hw_descr));
 413
 414         return total_len;
 415 }
 416
 417 u32 wl1271_tx_enabled_rates_get(struct wl1271 *wl, u32 rate_set)
 418 {
 419         struct ieee80211_supported_band *band;
 420         u32 enabled_rates = 0;
 421         int bit;
 422
 423         band = wl->hw->wiphy->bands[wl->band];
 424         for (bit = 0; bit < band->n_bitrates; bit++) {
 425                 if (rate_set & 0x1)
 426                         enabled_rates |= band->bitrates[bit].hw_value;
 427                 rate_set >>= 1;
 428         }
 429
 430 #ifdef CONFIG_WL12XX_HT
 431         /* MCS rates indication are on bits 16 - 23 */
 432         rate_set >>= HW_HT_RATES_OFFSET - band->n_bitrates;
 433
 434         for (bit = 0; bit < 8; bit++) {
 435                 if (rate_set & 0x1)
 436                         enabled_rates |= (CONF_HW_BIT_RATE_MCS_0 << bit);
 437                 rate_set >>= 1;
 438         }
 439 #endif
 440
 441         return enabled_rates;
 442 }
 443
 444 void wl1271_handle_tx_low_watermark(struct wl1271 *wl)
 445 {
 446         unsigned long flags;
 447         int i;
 448
 449         for (i = 0; i < NUM_TX_QUEUES; i++) {
 450                 if (test_bit(i, &wl->stopped_queues_map) &&
 451                     wl->tx_queue_count[i] <= WL1271_TX_QUEUE_LOW_WATERMARK) {
 452                         /* firmware buffer has space, restart queues */
 453                         spin_lock_irqsave(&wl->wl_lock, flags);
 454                         ieee80211_wake_queue(wl->hw,
 455                                              wl1271_tx_get_mac80211_queue(i));
 456                         clear_bit(i, &wl->stopped_queues_map);
 457                         spin_unlock_irqrestore(&wl->wl_lock, flags);
 458                 }
 459         }
 460 }
 461
 462 static struct sk_buff_head *wl1271_select_queue(struct wl1271 *wl,
 463                                                 struct sk_buff_head *queues)
 464 {
 465         int i, q = -1;
 466         u32 min_blks = 0xffffffff;
 467
 468         /*
 469          * Find a non-empty ac where:
 470          * 1. There are packets to transmit
 471          * 2. The FW has the least allocated blocks
 472          */
 473         for (i = 0; i < NUM_TX_QUEUES; i++)
 474                 if (!skb_queue_empty(&queues[i]) &&
 475                     (wl->tx_allocated_blocks[i] < min_blks)) {
 476                         q = i;
 477                         min_blks = wl->tx_allocated_blocks[q];
 478                 }
 479
 480         if (q == -1)
 481                 return NULL;
 482
 483         return &queues[q];
 484 }
 485
 486 static struct sk_buff *wl1271_sta_skb_dequeue(struct wl1271 *wl)
 487 {
 488         struct sk_buff *skb = NULL;
 489         unsigned long flags;
 490         struct sk_buff_head *queue;
 491
 492         queue = wl1271_select_queue(wl, wl->tx_queue);
 493         if (!queue)
 494                 goto out;
 495
 496         skb = skb_dequeue(queue);
 497
 498 out:
 499         if (skb) {
 500                 int q = wl1271_tx_get_queue(skb_get_queue_mapping(skb));
 501                 spin_lock_irqsave(&wl->wl_lock, flags);
 502                 wl->tx_queue_count[q]--;
 503                 spin_unlock_irqrestore(&wl->wl_lock, flags);
 504         }
 505
 506         return skb;
 507 }
 508
 509 static struct sk_buff *wl1271_ap_skb_dequeue(struct wl1271 *wl)
 510 {
 511         struct sk_buff *skb = NULL;
 512         unsigned long flags;
 513         int i, h, start_hlid;
 514         struct sk_buff_head *queue;
 515
 516         /* start from the link after the last one */
 517         start_hlid = (wl->last_tx_hlid + 1) % AP_MAX_LINKS;
 518
 519         /* dequeue according to AC, round robin on each link */
 520         for (i = 0; i < AP_MAX_LINKS; i++) {
 521                 h = (start_hlid + i) % AP_MAX_LINKS;
 522
 523                 /* only consider connected stations */
 524                 if (h >= WL1271_AP_STA_HLID_START &&
 525                     !test_bit(h - WL1271_AP_STA_HLID_START, wl->ap_hlid_map))
 526                         continue;
 527
 528                 queue = wl1271_select_queue(wl, wl->links[h].tx_queue);
 529                 if (!queue)
 530                         continue;
 531
 532                 skb = skb_dequeue(queue);
 533                 if (skb)
 534                         break;
 535         }
 536
 537         if (skb) {
 538                 int q = wl1271_tx_get_queue(skb_get_queue_mapping(skb));
 539                 wl->last_tx_hlid = h;
 540                 spin_lock_irqsave(&wl->wl_lock, flags);
 541                 wl->tx_queue_count[q]--;
 542                 spin_unlock_irqrestore(&wl->wl_lock, flags);
 543         } else {
 544                 wl->last_tx_hlid = 0;
 545         }
 546
 547         return skb;
 548 }
 549
 550 static struct sk_buff *wl1271_skb_dequeue(struct wl1271 *wl)
 551 {
 552         unsigned long flags;
 553         struct sk_buff *skb = NULL;
 554
 555         if (wl->bss_type == BSS_TYPE_AP_BSS)
 556                 skb = wl1271_ap_skb_dequeue(wl);
 557         else
 558                 skb = wl1271_sta_skb_dequeue(wl);
 559
 560         if (!skb &&
 561             test_and_clear_bit(WL1271_FLAG_DUMMY_PACKET_PENDING, &wl->flags)) {
 562                 int q;
 563
 564                 skb = wl->dummy_packet;
 565                 q = wl1271_tx_get_queue(skb_get_queue_mapping(skb));
 566                 spin_lock_irqsave(&wl->wl_lock, flags);
 567                 wl->tx_queue_count[q]--;
 568                 spin_unlock_irqrestore(&wl->wl_lock, flags);
 569         }
 570
 571         return skb;
 572 }
 573
 574 static void wl1271_skb_queue_head(struct wl1271 *wl, struct sk_buff *skb)
 575 {
 576         unsigned long flags;
 577         int q = wl1271_tx_get_queue(skb_get_queue_mapping(skb));
 578
 579         if (wl12xx_is_dummy_packet(wl, skb)) {
 580                 set_bit(WL1271_FLAG_DUMMY_PACKET_PENDING, &wl->flags);
 581         } else if (wl->bss_type == BSS_TYPE_AP_BSS) {
 582                 u8 hlid = wl1271_tx_get_hlid(skb);
 583                 skb_queue_head(&wl->links[hlid].tx_queue[q], skb);
 584
 585                 /* make sure we dequeue the same packet next time */
 586                 wl->last_tx_hlid = (hlid + AP_MAX_LINKS - 1) % AP_MAX_LINKS;
 587         } else {
 588                 skb_queue_head(&wl->tx_queue[q], skb);
 589         }
 590
 591         spin_lock_irqsave(&wl->wl_lock, flags);
 592         wl->tx_queue_count[q]++;
 593         spin_unlock_irqrestore(&wl->wl_lock, flags);
 594 }
 595
 596 static bool wl1271_tx_is_data_present(struct sk_buff *skb)
 597 {
 598         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)(skb->data);
 599
 600         return ieee80211_is_data_present(hdr->frame_control);
 601 }
 602
 603 void wl1271_tx_work_locked(struct wl1271 *wl)
 604 {
 605         struct sk_buff *skb;
 606         u32 buf_offset = 0;
 607         bool sent_packets = false;
 608         bool had_data = false;
 609         bool is_ap = (wl->bss_type == BSS_TYPE_AP_BSS);
 610         int ret;
 611
 612         if (unlikely(wl->state == WL1271_STATE_OFF))
 613                 return;
 614
 615         while ((skb = wl1271_skb_dequeue(wl))) {
 616                 if (wl1271_tx_is_data_present(skb))
 617                         had_data = true;
 618
 619                 ret = wl1271_prepare_tx_frame(wl, skb, buf_offset);
 620                 if (ret == -EAGAIN) {
 621                         /*
 622                          * Aggregation buffer is full.
 623                          * Flush buffer and try again.
 624                          */
 625                         wl1271_skb_queue_head(wl, skb);
 626                         wl1271_write(wl, WL1271_SLV_MEM_DATA, wl->aggr_buf,
 627                                      buf_offset, true);
 628                         sent_packets = true;
 629                         buf_offset = 0;
 630                         continue;
 631                 } else if (ret == -EBUSY) {
 632                         /*
 633                          * Firmware buffer is full.
 634                          * Queue back last skb, and stop aggregating.
 635                          */
 636                         wl1271_skb_queue_head(wl, skb);
 637                         /* No work left, avoid scheduling redundant tx work */
 638                         set_bit(WL1271_FLAG_FW_TX_BUSY, &wl->flags);
 639                         goto out_ack;
 640                 } else if (ret < 0) {
 641                         dev_kfree_skb(skb);
 642                         goto out_ack;
 643                 }
 644                 buf_offset += ret;
 645                 wl->tx_packets_count++;
 646         }
 647
 648 out_ack:
 649         if (buf_offset) {
 650                 wl1271_write(wl, WL1271_SLV_MEM_DATA, wl->aggr_buf,
 651                                 buf_offset, true);
 652                 sent_packets = true;
 653         }
 654         if (sent_packets) {
 655                 /*
 656                  * Interrupt the firmware with the new packets. This is only
 657                  * required for older hardware revisions
 658                  */
 659                 if (wl->quirks & WL12XX_QUIRK_END_OF_TRANSACTION)
 660                         wl1271_write32(wl, WL1271_HOST_WR_ACCESS,
 661                                        wl->tx_packets_count);
 662
 663                 wl1271_handle_tx_low_watermark(wl);
 664         }
 665         if (!is_ap && wl->conf.rx_streaming.interval && had_data &&
 666             (wl->conf.rx_streaming.always ||
 667              test_bit(WL1271_FLAG_SOFT_GEMINI, &wl->flags))) {
 668                 u32 timeout = wl->conf.rx_streaming.duration;
 669
 670                 /* enable rx streaming */
 671                 if (!test_bit(WL1271_FLAG_RX_STREAMING_STARTED, &wl->flags))
 672                         ieee80211_queue_work(wl->hw,
 673                                              &wl->rx_streaming_enable_work);
 674
 675                 mod_timer(&wl->rx_streaming_timer,
 676                           jiffies + msecs_to_jiffies(timeout));
 677         }
 678 }
 679
 680 void wl1271_tx_work(struct work_struct *work)
 681 {
 682         struct wl1271 *wl = container_of(work, struct wl1271, tx_work);
 683         int ret;
 684
 685         mutex_lock(&wl->mutex);
 686         ret = wl1271_ps_elp_wakeup(wl);
 687         if (ret < 0)
 688                 goto out;
 689
 690         wl1271_tx_work_locked(wl);
 691
 692         wl1271_ps_elp_sleep(wl);
 693 out:
 694         mutex_unlock(&wl->mutex);
 695 }
 696
 697 static void wl1271_tx_complete_packet(struct wl1271 *wl,
 698                                       struct wl1271_tx_hw_res_descr *result)
 699 {
 700         struct ieee80211_tx_info *info;
 701         struct sk_buff *skb;
 702         int id = result->id;
 703         int rate = -1;
 704         u8 retries = 0;
 705
 706         /* check for id legality */
 707         if (unlikely(id >= ACX_TX_DESCRIPTORS || wl->tx_frames[id] == NULL)) {
 708                 wl1271_warning("TX result illegal id: %d", id);
 709                 return;
 710         }
 711
 712         skb = wl->tx_frames[id];
 713         info = IEEE80211_SKB_CB(skb);
 714
 715         if (wl12xx_is_dummy_packet(wl, skb)) {
 716                 wl1271_free_tx_id(wl, id);
 717                 return;
 718         }
 719
 720         /* update the TX status info */
 721         if (result->status == TX_SUCCESS) {
 722                 if (!(info->flags & IEEE80211_TX_CTL_NO_ACK))
 723                         info->flags |= IEEE80211_TX_STAT_ACK;
 724                 rate = wl1271_rate_to_idx(result->rate_class_index, wl->band);
 725                 retries = result->ack_failures;
 726         } else if (result->status == TX_RETRY_EXCEEDED) {
 727                 wl->stats.excessive_retries++;
 728                 retries = result->ack_failures;
 729         }
 730
 731         info->status.rates[0].idx = rate;
 732         info->status.rates[0].count = retries;
 733         info->status.rates[0].flags = 0;
 734         info->status.ack_signal = -1;
 735
 736         wl->stats.retry_count += result->ack_failures;
 737
 738         /*
 739          * update sequence number only when relevant, i.e. only in
 740          * sessions of TKIP, AES and GEM (not in open or WEP sessions)
 741          */
 742         if (info->control.hw_key &&
 743             (info->control.hw_key->cipher == WLAN_CIPHER_SUITE_TKIP ||
 744              info->control.hw_key->cipher == WLAN_CIPHER_SUITE_CCMP ||
 745              info->control.hw_key->cipher == WL1271_CIPHER_SUITE_GEM)) {
 746                 u8 fw_lsb = result->tx_security_sequence_number_lsb;
 747                 u8 cur_lsb = wl->tx_security_last_seq_lsb;
 748
 749                 /*
 750                  * update security sequence number, taking care of potential
 751                  * wrap-around
 752                  */
 753                 wl->tx_security_seq += (fw_lsb - cur_lsb + 256) % 256;
 754                 wl->tx_security_last_seq_lsb = fw_lsb;
 755         }
 756
 757         /* remove private header from packet */
 758         skb_pull(skb, sizeof(struct wl1271_tx_hw_descr));
 759
 760         /* remove TKIP header space if present */
 761         if (info->control.hw_key &&
 762             info->control.hw_key->cipher == WLAN_CIPHER_SUITE_TKIP) {
 763                 int hdrlen = ieee80211_get_hdrlen_from_skb(skb);
 764                 memmove(skb->data + WL1271_TKIP_IV_SPACE, skb->data, hdrlen);
 765                 skb_pull(skb, WL1271_TKIP_IV_SPACE);
 766         }
 767
 768         wl1271_debug(DEBUG_TX, "tx status id %u skb 0x%p failures %u rate 0x%x"
 769                      " status 0x%x",
 770                      result->id, skb, result->ack_failures,
 771                      result->rate_class_index, result->status);
 772
 773         /* return the packet to the stack */
 774         skb_queue_tail(&wl->deferred_tx_queue, skb);
 775         queue_work(wl->freezable_wq, &wl->netstack_work);
 776         wl1271_free_tx_id(wl, result->id);
 777 }
 778
 779 /* Called upon reception of a TX complete interrupt */
 780 void wl1271_tx_complete(struct wl1271 *wl)
 781 {
 782         struct wl1271_acx_mem_map *memmap =
 783                 (struct wl1271_acx_mem_map *)wl->target_mem_map;
 784         u32 count, fw_counter;
 785         u32 i;
 786
 787         /* read the tx results from the chipset */
 788         wl1271_read(wl, le32_to_cpu(memmap->tx_result),
 789                     wl->tx_res_if, sizeof(*wl->tx_res_if), false);
 790         fw_counter = le32_to_cpu(wl->tx_res_if->tx_result_fw_counter);
 791
 792         /* write host counter to chipset (to ack) */
 793         wl1271_write32(wl, le32_to_cpu(memmap->tx_result) +
 794                        offsetof(struct wl1271_tx_hw_res_if,
 795                                 tx_result_host_counter), fw_counter);
 796
 797         count = fw_counter - wl->tx_results_count;
 798         wl1271_debug(DEBUG_TX, "tx_complete received, packets: %d", count);
 799
 800         /* verify that the result buffer is not getting overrun */
 801         if (unlikely(count > TX_HW_RESULT_QUEUE_LEN))
 802                 wl1271_warning("TX result overflow from chipset: %d", count);
 803
 804         /* process the results */
 805         for (i = 0; i < count; i++) {
 806                 struct wl1271_tx_hw_res_descr *result;
 807                 u8 offset = wl->tx_results_count & TX_HW_RESULT_QUEUE_LEN_MASK;
 808
 809                 /* process the packet */
 810                 result =  &(wl->tx_res_if->tx_results_queue[offset]);
 811                 wl1271_tx_complete_packet(wl, result);
 812
 813                 wl->tx_results_count++;
 814         }
 815 }
 816
 817 void wl1271_tx_reset_link_queues(struct wl1271 *wl, u8 hlid)
 818 {
 819         struct sk_buff *skb;
 820         int i;
 821         unsigned long flags;
 822         struct ieee80211_tx_info *info;
 823         int total[NUM_TX_QUEUES];
 824
 825         for (i = 0; i < NUM_TX_QUEUES; i++) {
 826                 total[i] = 0;
 827                 while ((skb = skb_dequeue(&wl->links[hlid].tx_queue[i]))) {
 828                         wl1271_debug(DEBUG_TX, "link freeing skb 0x%p", skb);
 829                         info = IEEE80211_SKB_CB(skb);
 830                         info->status.rates[0].idx = -1;
 831                         info->status.rates[0].count = 0;
 832                         ieee80211_tx_status_ni(wl->hw, skb);
 833                         total[i]++;
 834                 }
 835         }
 836
 837         spin_lock_irqsave(&wl->wl_lock, flags);
 838         for (i = 0; i < NUM_TX_QUEUES; i++)
 839                 wl->tx_queue_count[i] -= total[i];
 840         spin_unlock_irqrestore(&wl->wl_lock, flags);
 841
 842         wl1271_handle_tx_low_watermark(wl);
 843 }
 844
 845 /* caller must hold wl->mutex and TX must be stopped */
 846 void wl1271_tx_reset(struct wl1271 *wl, bool reset_tx_queues)
 847 {
 848         int i;
 849         struct sk_buff *skb;
 850         struct ieee80211_tx_info *info;
 851
 852         /* TX failure */
 853         if (wl->bss_type == BSS_TYPE_AP_BSS) {
 854                 for (i = 0; i < AP_MAX_LINKS; i++) {
 855                         wl1271_tx_reset_link_queues(wl, i);
 856                         wl->links[i].allocated_blks = 0;
 857                         wl->links[i].prev_freed_blks = 0;
 858                 }
 859
 860                 wl->last_tx_hlid = 0;
 861         } else {
 862                 for (i = 0; i < NUM_TX_QUEUES; i++) {
 863                         while ((skb = skb_dequeue(&wl->tx_queue[i]))) {
 864                                 wl1271_debug(DEBUG_TX, "freeing skb 0x%p",
 865                                              skb);
 866
 867                                 if (!wl12xx_is_dummy_packet(wl, skb)) {
 868                                         info = IEEE80211_SKB_CB(skb);
 869                                         info->status.rates[0].idx = -1;
 870                                         info->status.rates[0].count = 0;
 871                                         ieee80211_tx_status_ni(wl->hw, skb);
 872                                 }
 873                         }
 874                         wl->tx_queue_count[i] = 0;
 875                 }
 876         }
 877
 878         wl->stopped_queues_map = 0;
 879
 880         /*
 881          * Make sure the driver is at a consistent state, in case this
 882          * function is called from a context other than interface removal.
 883          * This call will always wake the TX queues.
 884          */
 885         if (reset_tx_queues)
 886                 wl1271_handle_tx_low_watermark(wl);
 887
 888         for (i = 0; i < ACX_TX_DESCRIPTORS; i++) {
 889                 if (wl->tx_frames[i] == NULL)
 890                         continue;
 891
 892                 skb = wl->tx_frames[i];
 893                 wl1271_free_tx_id(wl, i);
 894                 wl1271_debug(DEBUG_TX, "freeing skb 0x%p", skb);
 895
 896                 if (!wl12xx_is_dummy_packet(wl, skb)) {
 897                         /*
 898                          * Remove private headers before passing the skb to
 899                          * mac80211
 900                          */
 901                         info = IEEE80211_SKB_CB(skb);
 902                         skb_pull(skb, sizeof(struct wl1271_tx_hw_descr));
 903                         if (info->control.hw_key &&
 904                             info->control.hw_key->cipher ==
 905                             WLAN_CIPHER_SUITE_TKIP) {
 906                                 int hdrlen = ieee80211_get_hdrlen_from_skb(skb);
 907                                 memmove(skb->data + WL1271_TKIP_IV_SPACE,
 908                                         skb->data, hdrlen);
 909                                 skb_pull(skb, WL1271_TKIP_IV_SPACE);
 910                         }
 911
 912                         info->status.rates[0].idx = -1;
 913                         info->status.rates[0].count = 0;
 914
 915                         ieee80211_tx_status_ni(wl->hw, skb);
 916                 }
 917         }
 918 }
 919
 920 #define WL1271_TX_FLUSH_TIMEOUT 500000
 921
 922 /* caller must *NOT* hold wl->mutex */
 923 void wl1271_tx_flush(struct wl1271 *wl)
 924 {
 925         unsigned long timeout;
 926         timeout = jiffies + usecs_to_jiffies(WL1271_TX_FLUSH_TIMEOUT);
 927
 928         while (!time_after(jiffies, timeout)) {
 929                 mutex_lock(&wl->mutex);
 930                 wl1271_debug(DEBUG_TX, "flushing tx buffer: %d %d",
 931                              wl->tx_frames_cnt,
 932                              wl1271_tx_total_queue_count(wl));
 933                 if ((wl->tx_frames_cnt == 0) &&
 934                     (wl1271_tx_total_queue_count(wl) == 0)) {
 935                         mutex_unlock(&wl->mutex);
 936                         return;
 937                 }
 938                 mutex_unlock(&wl->mutex);
 939                 msleep(1);
 940         }
 941
 942         wl1271_warning("Unable to flush all TX buffers, timed out.");
 943 }
 944
 945 u32 wl1271_tx_min_rate_get(struct wl1271 *wl)
 946 {
 947         int i;
 948         u32 rate = 0;
 949
 950         if (!wl->basic_rate_set) {
 951                 WARN_ON(1);
 952                 wl->basic_rate_set = wl->conf.tx.basic_rate;
 953         }
 954
 955         for (i = 0; !rate; i++) {
 956                 if ((wl->basic_rate_set >> i) & 0x1)
 957                         rate = 1 << i;
 958         }
 959
 960         return rate;
 961 }