drivers/net/wireless/ath/ath6kl/htc_mbox.c

   1 /*
   2  * Copyright (c) 2007-2011 Atheros Communications Inc.
   3  * Copyright (c) 2011-2012 Qualcomm Atheros, Inc.
   4  *
   5  * Permission to use, copy, modify, and/or distribute this software for any
   6  * purpose with or without fee is hereby granted, provided that the above
   7  * copyright notice and this permission notice appear in all copies.
   8  *
   9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  16  */
  17
  18 #include "core.h"
  19 #include "hif.h"
  20 #include "debug.h"
  21 #include "hif-ops.h"
  22 #include "trace.h"
  23
  24 #include <linux/unaligned.h>
  25
  26 #define CALC_TXRX_PADDED_LEN(dev, len)  (__ALIGN_MASK((len), (dev)->block_mask))
  27
  28 static void ath6kl_htc_mbox_cleanup(struct htc_target *target);
  29 static void ath6kl_htc_mbox_stop(struct htc_target *target);
  30 static int ath6kl_htc_mbox_add_rxbuf_multiple(struct htc_target *target,
  31                                               struct list_head *pkt_queue);
  32 static void ath6kl_htc_set_credit_dist(struct htc_target *target,
  33                                        struct ath6kl_htc_credit_info *cred_info,
  34                                        u16 svc_pri_order[], int len);
  35
  36 /* threshold to re-enable Tx bundling for an AC*/
  37 #define TX_RESUME_BUNDLE_THRESHOLD      1500
  38
  39 /* Functions for Tx credit handling */
  40 static void ath6kl_credit_deposit(struct ath6kl_htc_credit_info *cred_info,
  41                                   struct htc_endpoint_credit_dist *ep_dist,
  42                                   int credits)
  43 {
  44         ath6kl_dbg(ATH6KL_DBG_CREDIT, "credit deposit ep %d credits %d\n",
  45                    ep_dist->endpoint, credits);
  46
  47         ep_dist->credits += credits;
  48         ep_dist->cred_assngd += credits;
  49         cred_info->cur_free_credits -= credits;
  50 }
  51
  52 static void ath6kl_credit_init(struct ath6kl_htc_credit_info *cred_info,
  53                                struct list_head *ep_list,
  54                                int tot_credits)
  55 {
  56         struct htc_endpoint_credit_dist *cur_ep_dist;
  57         int count;
  58
  59         ath6kl_dbg(ATH6KL_DBG_CREDIT, "credit init total %d\n", tot_credits);
  60
  61         cred_info->cur_free_credits = tot_credits;
  62         cred_info->total_avail_credits = tot_credits;
  63
  64         list_for_each_entry(cur_ep_dist, ep_list, list) {
  65                 if (cur_ep_dist->endpoint == ENDPOINT_0)
  66                         continue;
  67
  68                 cur_ep_dist->cred_min = cur_ep_dist->cred_per_msg;
  69
  70                 if (tot_credits > 4) {
  71                         if ((cur_ep_dist->svc_id == WMI_DATA_BK_SVC) ||
  72                             (cur_ep_dist->svc_id == WMI_DATA_BE_SVC)) {
  73                                 ath6kl_credit_deposit(cred_info,
  74                                                       cur_ep_dist,
  75                                                       cur_ep_dist->cred_min);
  76                                 cur_ep_dist->dist_flags |= HTC_EP_ACTIVE;
  77                         }
  78                 }
  79
  80                 if (cur_ep_dist->svc_id == WMI_CONTROL_SVC) {
  81                         ath6kl_credit_deposit(cred_info, cur_ep_dist,
  82                                               cur_ep_dist->cred_min);
  83                         /*
  84                          * Control service is always marked active, it
  85                          * never goes inactive EVER.
  86                          */
  87                         cur_ep_dist->dist_flags |= HTC_EP_ACTIVE;
  88                 }
  89
  90                 /*
  91                  * Streams have to be created (explicit | implicit) for all
  92                  * kinds of traffic. BE endpoints are also inactive in the
  93                  * beginning. When BE traffic starts it creates implicit
  94                  * streams that redistributes credits.
  95                  *
  96                  * Note: all other endpoints have minimums set but are
  97                  * initially given NO credits. credits will be distributed
  98                  * as traffic activity demands
  99                  */
 100         }
 101
 102         /*
 103          * For ath6kl_credit_seek function,
 104          * it use list_for_each_entry_reverse to walk around the whole ep list.
 105          * Therefore assign this lowestpri_ep_dist after walk around the ep_list
 106          */
 107         cred_info->lowestpri_ep_dist = cur_ep_dist->list;
 108
 109         WARN_ON(cred_info->cur_free_credits <= 0);
 110
 111         list_for_each_entry(cur_ep_dist, ep_list, list) {
 112                 if (cur_ep_dist->endpoint == ENDPOINT_0)
 113                         continue;
 114
 115                 if (cur_ep_dist->svc_id == WMI_CONTROL_SVC) {
 116                         cur_ep_dist->cred_norm = cur_ep_dist->cred_per_msg;
 117                 } else {
 118                         /*
 119                          * For the remaining data endpoints, we assume that
 120                          * each cred_per_msg are the same. We use a simple
 121                          * calculation here, we take the remaining credits
 122                          * and determine how many max messages this can
 123                          * cover and then set each endpoint's normal value
 124                          * equal to 3/4 this amount.
 125                          */
 126                         count = (cred_info->cur_free_credits /
 127                                  cur_ep_dist->cred_per_msg)
 128                                 * cur_ep_dist->cred_per_msg;
 129                         count = (count * 3) >> 2;
 130                         count = max(count, cur_ep_dist->cred_per_msg);
 131                         cur_ep_dist->cred_norm = count;
 132                 }
 133
 134                 ath6kl_dbg(ATH6KL_DBG_CREDIT,
 135                            "credit ep %d svc_id %d credits %d per_msg %d norm %d min %d\n",
 136                            cur_ep_dist->endpoint,
 137                            cur_ep_dist->svc_id,
 138                            cur_ep_dist->credits,
 139                            cur_ep_dist->cred_per_msg,
 140                            cur_ep_dist->cred_norm,
 141                            cur_ep_dist->cred_min);
 142         }
 143 }
 144
 145 /* initialize and setup credit distribution */
 146 static int ath6kl_htc_mbox_credit_setup(struct htc_target *htc_target,
 147                                struct ath6kl_htc_credit_info *cred_info)
 148 {
 149         u16 servicepriority[5];
 150
 151         memset(cred_info, 0, sizeof(struct ath6kl_htc_credit_info));
 152
 153         servicepriority[0] = WMI_CONTROL_SVC;  /* highest */
 154         servicepriority[1] = WMI_DATA_VO_SVC;
 155         servicepriority[2] = WMI_DATA_VI_SVC;
 156         servicepriority[3] = WMI_DATA_BE_SVC;
 157         servicepriority[4] = WMI_DATA_BK_SVC; /* lowest */
 158
 159         /* set priority list */
 160         ath6kl_htc_set_credit_dist(htc_target, cred_info, servicepriority, 5);
 161
 162         return 0;
 163 }
 164
 165 /* reduce an ep's credits back to a set limit */
 166 static void ath6kl_credit_reduce(struct ath6kl_htc_credit_info *cred_info,
 167                                  struct htc_endpoint_credit_dist *ep_dist,
 168                                  int limit)
 169 {
 170         int credits;
 171
 172         ath6kl_dbg(ATH6KL_DBG_CREDIT, "credit reduce ep %d limit %d\n",
 173                    ep_dist->endpoint, limit);
 174
 175         ep_dist->cred_assngd = limit;
 176
 177         if (ep_dist->credits <= limit)
 178                 return;
 179
 180         credits = ep_dist->credits - limit;
 181         ep_dist->credits -= credits;
 182         cred_info->cur_free_credits += credits;
 183 }
 184
 185 static void ath6kl_credit_update(struct ath6kl_htc_credit_info *cred_info,
 186                                  struct list_head *epdist_list)
 187 {
 188         struct htc_endpoint_credit_dist *cur_list;
 189
 190         list_for_each_entry(cur_list, epdist_list, list) {
 191                 if (cur_list->endpoint == ENDPOINT_0)
 192                         continue;
 193
 194                 if (cur_list->cred_to_dist > 0) {
 195                         cur_list->credits += cur_list->cred_to_dist;
 196                         cur_list->cred_to_dist = 0;
 197
 198                         if (cur_list->credits > cur_list->cred_assngd)
 199                                 ath6kl_credit_reduce(cred_info,
 200                                                      cur_list,
 201                                                      cur_list->cred_assngd);
 202
 203                         if (cur_list->credits > cur_list->cred_norm)
 204                                 ath6kl_credit_reduce(cred_info, cur_list,
 205                                                      cur_list->cred_norm);
 206
 207                         if (!(cur_list->dist_flags & HTC_EP_ACTIVE)) {
 208                                 if (cur_list->txq_depth == 0)
 209                                         ath6kl_credit_reduce(cred_info,
 210                                                              cur_list, 0);
 211                         }
 212                 }
 213         }
 214 }
 215
 216 /*
 217  * HTC has an endpoint that needs credits, ep_dist is the endpoint in
 218  * question.
 219  */
 220 static void ath6kl_credit_seek(struct ath6kl_htc_credit_info *cred_info,
 221                                 struct htc_endpoint_credit_dist *ep_dist)
 222 {
 223         struct htc_endpoint_credit_dist *curdist_list;
 224         int credits = 0;
 225         int need;
 226
 227         if (ep_dist->svc_id == WMI_CONTROL_SVC)
 228                 goto out;
 229
 230         if ((ep_dist->svc_id == WMI_DATA_VI_SVC) ||
 231             (ep_dist->svc_id == WMI_DATA_VO_SVC))
 232                 if ((ep_dist->cred_assngd >= ep_dist->cred_norm))
 233                         goto out;
 234
 235         /*
 236          * For all other services, we follow a simple algorithm of:
 237          *
 238          * 1. checking the free pool for credits
 239          * 2. checking lower priority endpoints for credits to take
 240          */
 241
 242         credits = min(cred_info->cur_free_credits, ep_dist->seek_cred);
 243
 244         if (credits >= ep_dist->seek_cred)
 245                 goto out;
 246
 247         /*
 248          * We don't have enough in the free pool, try taking away from
 249          * lower priority services The rule for taking away credits:
 250          *
 251          *   1. Only take from lower priority endpoints
 252          *   2. Only take what is allocated above the minimum (never
 253          *      starve an endpoint completely)
 254          *   3. Only take what you need.
 255          */
 256
 257         list_for_each_entry_reverse(curdist_list,
 258                                     &cred_info->lowestpri_ep_dist,
 259                                     list) {
 260                 if (curdist_list == ep_dist)
 261                         break;
 262
 263                 need = ep_dist->seek_cred - cred_info->cur_free_credits;
 264
 265                 if ((curdist_list->cred_assngd - need) >=
 266                      curdist_list->cred_min) {
 267                         /*
 268                          * The current one has been allocated more than
 269                          * it's minimum and it has enough credits assigned
 270                          * above it's minimum to fulfill our need try to
 271                          * take away just enough to fulfill our need.
 272                          */
 273                         ath6kl_credit_reduce(cred_info, curdist_list,
 274                                              curdist_list->cred_assngd - need);
 275
 276                         if (cred_info->cur_free_credits >=
 277                             ep_dist->seek_cred)
 278                                 break;
 279                 }
 280
 281                 if (curdist_list->endpoint == ENDPOINT_0)
 282                         break;
 283         }
 284
 285         credits = min(cred_info->cur_free_credits, ep_dist->seek_cred);
 286
 287 out:
 288         /* did we find some credits? */
 289         if (credits)
 290                 ath6kl_credit_deposit(cred_info, ep_dist, credits);
 291
 292         ep_dist->seek_cred = 0;
 293 }
 294
 295 /* redistribute credits based on activity change */
 296 static void ath6kl_credit_redistribute(struct ath6kl_htc_credit_info *info,
 297                                        struct list_head *ep_dist_list)
 298 {
 299         struct htc_endpoint_credit_dist *curdist_list;
 300
 301         list_for_each_entry(curdist_list, ep_dist_list, list) {
 302                 if (curdist_list->endpoint == ENDPOINT_0)
 303                         continue;
 304
 305                 if ((curdist_list->svc_id == WMI_DATA_BK_SVC)  ||
 306                     (curdist_list->svc_id == WMI_DATA_BE_SVC))
 307                         curdist_list->dist_flags |= HTC_EP_ACTIVE;
 308
 309                 if ((curdist_list->svc_id != WMI_CONTROL_SVC) &&
 310                     !(curdist_list->dist_flags & HTC_EP_ACTIVE)) {
 311                         if (curdist_list->txq_depth == 0)
 312                                 ath6kl_credit_reduce(info, curdist_list, 0);
 313                         else
 314                                 ath6kl_credit_reduce(info,
 315                                                      curdist_list,
 316                                                      curdist_list->cred_min);
 317                 }
 318         }
 319 }
 320
 321 /*
 322  *
 323  * This function is invoked whenever endpoints require credit
 324  * distributions. A lock is held while this function is invoked, this
 325  * function shall NOT block. The ep_dist_list is a list of distribution
 326  * structures in prioritized order as defined by the call to the
 327  * htc_set_credit_dist() api.
 328  */
 329 static void ath6kl_credit_distribute(struct ath6kl_htc_credit_info *cred_info,
 330                                      struct list_head *ep_dist_list,
 331                               enum htc_credit_dist_reason reason)
 332 {
 333         switch (reason) {
 334         case HTC_CREDIT_DIST_SEND_COMPLETE:
 335                 ath6kl_credit_update(cred_info, ep_dist_list);
 336                 break;
 337         case HTC_CREDIT_DIST_ACTIVITY_CHANGE:
 338                 ath6kl_credit_redistribute(cred_info, ep_dist_list);
 339                 break;
 340         default:
 341                 break;
 342         }
 343
 344         WARN_ON(cred_info->cur_free_credits > cred_info->total_avail_credits);
 345         WARN_ON(cred_info->cur_free_credits < 0);
 346 }
 347
 348 static void ath6kl_htc_tx_buf_align(u8 **buf, unsigned long len)
 349 {
 350         u8 *align_addr;
 351
 352         if (!IS_ALIGNED((unsigned long) *buf, 4)) {
 353                 align_addr = PTR_ALIGN(*buf - 4, 4);
 354                 memmove(align_addr, *buf, len);
 355                 *buf = align_addr;
 356         }
 357 }
 358
 359 static void ath6kl_htc_tx_prep_pkt(struct htc_packet *packet, u8 flags,
 360                                    int ctrl0, int ctrl1)
 361 {
 362         struct htc_frame_hdr *hdr;
 363
 364         packet->buf -= HTC_HDR_LENGTH;
 365         hdr =  (struct htc_frame_hdr *)packet->buf;
 366
 367         put_unaligned_le16(packet->act_len, &hdr->payld_len);
 368         hdr->flags = flags;
 369         hdr->eid = packet->endpoint;
 370         hdr->ctrl[0] = ctrl0;
 371         hdr->ctrl[1] = ctrl1;
 372 }
 373
 374 static void htc_reclaim_txctrl_buf(struct htc_target *target,
 375                                    struct htc_packet *pkt)
 376 {
 377         spin_lock_bh(&target->htc_lock);
 378         list_add_tail(&pkt->list, &target->free_ctrl_txbuf);
 379         spin_unlock_bh(&target->htc_lock);
 380 }
 381
 382 static struct htc_packet *htc_get_control_buf(struct htc_target *target,
 383                                               bool tx)
 384 {
 385         struct htc_packet *packet = NULL;
 386         struct list_head *buf_list;
 387
 388         buf_list = tx ? &target->free_ctrl_txbuf : &target->free_ctrl_rxbuf;
 389
 390         spin_lock_bh(&target->htc_lock);
 391
 392         if (list_empty(buf_list)) {
 393                 spin_unlock_bh(&target->htc_lock);
 394                 return NULL;
 395         }
 396
 397         packet = list_first_entry(buf_list, struct htc_packet, list);
 398         list_del(&packet->list);
 399         spin_unlock_bh(&target->htc_lock);
 400
 401         if (tx)
 402                 packet->buf = packet->buf_start + HTC_HDR_LENGTH;
 403
 404         return packet;
 405 }
 406
 407 static void htc_tx_comp_update(struct htc_target *target,
 408                                struct htc_endpoint *endpoint,
 409                                struct htc_packet *packet)
 410 {
 411         packet->completion = NULL;
 412         packet->buf += HTC_HDR_LENGTH;
 413
 414         if (!packet->status)
 415                 return;
 416
 417         ath6kl_err("req failed (status:%d, ep:%d, len:%d creds:%d)\n",
 418                    packet->status, packet->endpoint, packet->act_len,
 419                    packet->info.tx.cred_used);
 420
 421         /* on failure to submit, reclaim credits for this packet */
 422         spin_lock_bh(&target->tx_lock);
 423         endpoint->cred_dist.cred_to_dist +=
 424                                 packet->info.tx.cred_used;
 425         endpoint->cred_dist.txq_depth = get_queue_depth(&endpoint->txq);
 426
 427         ath6kl_dbg(ATH6KL_DBG_HTC, "htc tx ctxt 0x%p dist 0x%p\n",
 428                    target->credit_info, &target->cred_dist_list);
 429
 430         ath6kl_credit_distribute(target->credit_info,
 431                                  &target->cred_dist_list,
 432                                  HTC_CREDIT_DIST_SEND_COMPLETE);
 433
 434         spin_unlock_bh(&target->tx_lock);
 435 }
 436
 437 static void htc_tx_complete(struct htc_endpoint *endpoint,
 438                             struct list_head *txq)
 439 {
 440         if (list_empty(txq))
 441                 return;
 442
 443         ath6kl_dbg(ATH6KL_DBG_HTC,
 444                    "htc tx complete ep %d pkts %d\n",
 445                    endpoint->eid, get_queue_depth(txq));
 446
 447         ath6kl_tx_complete(endpoint->target, txq);
 448 }
 449
 450 static void htc_tx_comp_handler(struct htc_target *target,
 451                                 struct htc_packet *packet)
 452 {
 453         struct htc_endpoint *endpoint = &target->endpoint[packet->endpoint];
 454         struct list_head container;
 455
 456         ath6kl_dbg(ATH6KL_DBG_HTC, "htc tx complete seqno %d\n",
 457                    packet->info.tx.seqno);
 458
 459         htc_tx_comp_update(target, endpoint, packet);
 460         INIT_LIST_HEAD(&container);
 461         list_add_tail(&packet->list, &container);
 462         /* do completion */
 463         htc_tx_complete(endpoint, &container);
 464 }
 465
 466 static void htc_async_tx_scat_complete(struct htc_target *target,
 467                                        struct hif_scatter_req *scat_req)
 468 {
 469         struct htc_endpoint *endpoint;
 470         struct htc_packet *packet;
 471         struct list_head tx_compq;
 472         int i;
 473
 474         INIT_LIST_HEAD(&tx_compq);
 475
 476         ath6kl_dbg(ATH6KL_DBG_HTC,
 477                    "htc tx scat complete len %d entries %d\n",
 478                    scat_req->len, scat_req->scat_entries);
 479
 480         if (scat_req->status)
 481                 ath6kl_err("send scatter req failed: %d\n", scat_req->status);
 482
 483         packet = scat_req->scat_list[0].packet;
 484         endpoint = &target->endpoint[packet->endpoint];
 485
 486         /* walk through the scatter list and process */
 487         for (i = 0; i < scat_req->scat_entries; i++) {
 488                 packet = scat_req->scat_list[i].packet;
 489                 if (!packet) {
 490                         WARN_ON(1);
 491                         return;
 492                 }
 493
 494                 packet->status = scat_req->status;
 495                 htc_tx_comp_update(target, endpoint, packet);
 496                 list_add_tail(&packet->list, &tx_compq);
 497         }
 498
 499         /* free scatter request */
 500         hif_scatter_req_add(target->dev->ar, scat_req);
 501
 502         /* complete all packets */
 503         htc_tx_complete(endpoint, &tx_compq);
 504 }
 505
 506 static int ath6kl_htc_tx_issue(struct htc_target *target,
 507                                struct htc_packet *packet)
 508 {
 509         int status;
 510         bool sync = false;
 511         u32 padded_len, send_len;
 512
 513         if (!packet->completion)
 514                 sync = true;
 515
 516         send_len = packet->act_len + HTC_HDR_LENGTH;
 517
 518         padded_len = CALC_TXRX_PADDED_LEN(target, send_len);
 519
 520         ath6kl_dbg(ATH6KL_DBG_HTC,
 521                    "htc tx issue len %d seqno %d padded_len %d mbox 0x%X %s\n",
 522                    send_len, packet->info.tx.seqno, padded_len,
 523                    target->dev->ar->mbox_info.htc_addr,
 524                    sync ? "sync" : "async");
 525
 526         if (sync) {
 527                 status = hif_read_write_sync(target->dev->ar,
 528                                 target->dev->ar->mbox_info.htc_addr,
 529                                  packet->buf, padded_len,
 530                                  HIF_WR_SYNC_BLOCK_INC);
 531
 532                 packet->status = status;
 533                 packet->buf += HTC_HDR_LENGTH;
 534         } else
 535                 status = hif_write_async(target->dev->ar,
 536                                 target->dev->ar->mbox_info.htc_addr,
 537                                 packet->buf, padded_len,
 538                                 HIF_WR_ASYNC_BLOCK_INC, packet);
 539
 540         trace_ath6kl_htc_tx(status, packet->endpoint, packet->buf, send_len);
 541
 542         return status;
 543 }
 544
 545 static int htc_check_credits(struct htc_target *target,
 546                              struct htc_endpoint *ep, u8 *flags,
 547                              enum htc_endpoint_id eid, unsigned int len,
 548                              int *req_cred)
 549 {
 550         *req_cred = (len > target->tgt_cred_sz) ?
 551                      DIV_ROUND_UP(len, target->tgt_cred_sz) : 1;
 552
 553         ath6kl_dbg(ATH6KL_DBG_CREDIT, "credit check need %d got %d\n",
 554                    *req_cred, ep->cred_dist.credits);
 555
 556         if (ep->cred_dist.credits < *req_cred) {
 557                 if (eid == ENDPOINT_0)
 558                         return -EINVAL;
 559
 560                 /* Seek more credits */
 561                 ep->cred_dist.seek_cred = *req_cred - ep->cred_dist.credits;
 562
 563                 ath6kl_credit_seek(target->credit_info, &ep->cred_dist);
 564
 565                 ep->cred_dist.seek_cred = 0;
 566
 567                 if (ep->cred_dist.credits < *req_cred) {
 568                         ath6kl_dbg(ATH6KL_DBG_CREDIT,
 569                                    "credit not found for ep %d\n",
 570                                    eid);
 571                         return -EINVAL;
 572                 }
 573         }
 574
 575         ep->cred_dist.credits -= *req_cred;
 576         ep->ep_st.cred_cosumd += *req_cred;
 577
 578          /* When we are getting low on credits, ask for more */
 579         if (ep->cred_dist.credits < ep->cred_dist.cred_per_msg) {
 580                 ep->cred_dist.seek_cred =
 581                 ep->cred_dist.cred_per_msg - ep->cred_dist.credits;
 582
 583                 ath6kl_credit_seek(target->credit_info, &ep->cred_dist);
 584
 585                 /* see if we were successful in getting more */
 586                 if (ep->cred_dist.credits < ep->cred_dist.cred_per_msg) {
 587                         /* tell the target we need credits ASAP! */
 588                         *flags |= HTC_FLAGS_NEED_CREDIT_UPDATE;
 589                         ep->ep_st.cred_low_indicate += 1;
 590                         ath6kl_dbg(ATH6KL_DBG_CREDIT,
 591                                    "credit we need credits asap\n");
 592                 }
 593         }
 594
 595         return 0;
 596 }
 597
 598 static void ath6kl_htc_tx_pkts_get(struct htc_target *target,
 599                                    struct htc_endpoint *endpoint,
 600                                    struct list_head *queue)
 601 {
 602         int req_cred;
 603         u8 flags;
 604         struct htc_packet *packet;
 605         unsigned int len;
 606
 607         while (true) {
 608                 flags = 0;
 609
 610                 if (list_empty(&endpoint->txq))
 611                         break;
 612                 packet = list_first_entry(&endpoint->txq, struct htc_packet,
 613                                           list);
 614
 615                 ath6kl_dbg(ATH6KL_DBG_HTC,
 616                            "htc tx got packet 0x%p queue depth %d\n",
 617                            packet, get_queue_depth(&endpoint->txq));
 618
 619                 len = CALC_TXRX_PADDED_LEN(target,
 620                                            packet->act_len + HTC_HDR_LENGTH);
 621
 622                 if (htc_check_credits(target, endpoint, &flags,
 623                                       packet->endpoint, len, &req_cred))
 624                         break;
 625
 626                 /* now we can fully move onto caller's queue */
 627                 packet = list_first_entry(&endpoint->txq, struct htc_packet,
 628                                           list);
 629                 list_move_tail(&packet->list, queue);
 630
 631                 /* save the number of credits this packet consumed */
 632                 packet->info.tx.cred_used = req_cred;
 633
 634                 /* all TX packets are handled asynchronously */
 635                 packet->completion = htc_tx_comp_handler;
 636                 packet->context = target;
 637                 endpoint->ep_st.tx_issued += 1;
 638
 639                 /* save send flags */
 640                 packet->info.tx.flags = flags;
 641                 packet->info.tx.seqno = endpoint->seqno;
 642                 endpoint->seqno++;
 643         }
 644 }
 645
 646 /* See if the padded tx length falls on a credit boundary */
 647 static int htc_get_credit_padding(unsigned int cred_sz, int *len,
 648                                   struct htc_endpoint *ep)
 649 {
 650         int rem_cred, cred_pad;
 651
 652         rem_cred = *len % cred_sz;
 653
 654         /* No padding needed */
 655         if  (!rem_cred)
 656                 return 0;
 657
 658         if (!(ep->conn_flags & HTC_FLGS_TX_BNDL_PAD_EN))
 659                 return -1;
 660
 661         /*
 662          * The transfer consumes a "partial" credit, this
 663          * packet cannot be bundled unless we add
 664          * additional "dummy" padding (max 255 bytes) to
 665          * consume the entire credit.
 666          */
 667         cred_pad = *len < cred_sz ? (cred_sz - *len) : rem_cred;
 668
 669         if ((cred_pad > 0) && (cred_pad <= 255))
 670                 *len += cred_pad;
 671         else
 672                 /* The amount of padding is too large, send as non-bundled */
 673                 return -1;
 674
 675         return cred_pad;
 676 }
 677
 678 static int ath6kl_htc_tx_setup_scat_list(struct htc_target *target,
 679                                          struct htc_endpoint *endpoint,
 680                                          struct hif_scatter_req *scat_req,
 681                                          int n_scat,
 682                                          struct list_head *queue)
 683 {
 684         struct htc_packet *packet;
 685         int i, len, rem_scat, cred_pad;
 686         int status = 0;
 687         u8 flags;
 688
 689         rem_scat = target->max_tx_bndl_sz;
 690
 691         for (i = 0; i < n_scat; i++) {
 692                 scat_req->scat_list[i].packet = NULL;
 693
 694                 if (list_empty(queue))
 695                         break;
 696
 697                 packet = list_first_entry(queue, struct htc_packet, list);
 698                 len = CALC_TXRX_PADDED_LEN(target,
 699                                            packet->act_len + HTC_HDR_LENGTH);
 700
 701                 cred_pad = htc_get_credit_padding(target->tgt_cred_sz,
 702                                                   &len, endpoint);
 703                 if (cred_pad < 0 || rem_scat < len) {
 704                         status = -ENOSPC;
 705                         break;
 706                 }
 707
 708                 rem_scat -= len;
 709                 /* now remove it from the queue */
 710                 list_del(&packet->list);
 711
 712                 scat_req->scat_list[i].packet = packet;
 713                 /* prepare packet and flag message as part of a send bundle */
 714                 flags = packet->info.tx.flags | HTC_FLAGS_SEND_BUNDLE;
 715                 ath6kl_htc_tx_prep_pkt(packet, flags,
 716                                        cred_pad, packet->info.tx.seqno);
 717                 /* Make sure the buffer is 4-byte aligned */
 718                 ath6kl_htc_tx_buf_align(&packet->buf,
 719                                         packet->act_len + HTC_HDR_LENGTH);
 720                 scat_req->scat_list[i].buf = packet->buf;
 721                 scat_req->scat_list[i].len = len;
 722
 723                 scat_req->len += len;
 724                 scat_req->scat_entries++;
 725                 ath6kl_dbg(ATH6KL_DBG_HTC,
 726                            "htc tx adding (%d) pkt 0x%p seqno %d len %d remaining %d\n",
 727                            i, packet, packet->info.tx.seqno, len, rem_scat);
 728         }
 729
 730         /* Roll back scatter setup in case of any failure */
 731         if (scat_req->scat_entries < HTC_MIN_HTC_MSGS_TO_BUNDLE) {
 732                 for (i = scat_req->scat_entries - 1; i >= 0; i--) {
 733                         packet = scat_req->scat_list[i].packet;
 734                         if (packet) {
 735                                 packet->buf += HTC_HDR_LENGTH;
 736                                 list_add(&packet->list, queue);
 737                         }
 738                 }
 739                 return -EAGAIN;
 740         }
 741
 742         return status;
 743 }
 744
 745 /*
 746  * Drain a queue and send as bundles this function may return without fully
 747  * draining the queue when
 748  *
 749  *    1. scatter resources are exhausted
 750  *    2. a message that will consume a partial credit will stop the
 751  *    bundling process early
 752  *    3. we drop below the minimum number of messages for a bundle
 753  */
 754 static void ath6kl_htc_tx_bundle(struct htc_endpoint *endpoint,
 755                                  struct list_head *queue,
 756                                  int *sent_bundle, int *n_bundle_pkts)
 757 {
 758         struct htc_target *target = endpoint->target;
 759         struct hif_scatter_req *scat_req = NULL;
 760         int n_scat, n_sent_bundle = 0, tot_pkts_bundle = 0, i;
 761         struct htc_packet *packet;
 762         int status;
 763         u32 txb_mask;
 764         u8 ac = WMM_NUM_AC;
 765
 766         if ((HTC_CTRL_RSVD_SVC != endpoint->svc_id) &&
 767             (WMI_CONTROL_SVC != endpoint->svc_id))
 768                 ac = target->dev->ar->ep2ac_map[endpoint->eid];
 769
 770         while (true) {
 771                 status = 0;
 772                 n_scat = get_queue_depth(queue);
 773                 n_scat = min(n_scat, target->msg_per_bndl_max);
 774
 775                 if (n_scat < HTC_MIN_HTC_MSGS_TO_BUNDLE)
 776                         /* not enough to bundle */
 777                         break;
 778
 779                 scat_req = hif_scatter_req_get(target->dev->ar);
 780
 781                 if (!scat_req) {
 782                         /* no scatter resources  */
 783                         ath6kl_dbg(ATH6KL_DBG_HTC,
 784                                    "htc tx no more scatter resources\n");
 785                         break;
 786                 }
 787
 788                 if ((ac < WMM_NUM_AC) && (ac != WMM_AC_BK)) {
 789                         if (WMM_AC_BE == ac)
 790                                 /*
 791                                  * BE, BK have priorities and bit
 792                                  * positions reversed
 793                                  */
 794                                 txb_mask = (1 << WMM_AC_BK);
 795                         else
 796                                 /*
 797                                  * any AC with priority lower than
 798                                  * itself
 799                                  */
 800                                 txb_mask = ((1 << ac) - 1);
 801
 802                         /*
 803                          * when the scatter request resources drop below a
 804                          * certain threshold, disable Tx bundling for all
 805                          * AC's with priority lower than the current requesting
 806                          * AC. Otherwise re-enable Tx bundling for them
 807                          */
 808                         if (scat_req->scat_q_depth < ATH6KL_SCATTER_REQS)
 809                                 target->tx_bndl_mask &= ~txb_mask;
 810                         else
 811                                 target->tx_bndl_mask |= txb_mask;
 812                 }
 813
 814                 ath6kl_dbg(ATH6KL_DBG_HTC, "htc tx pkts to scatter: %d\n",
 815                            n_scat);
 816
 817                 scat_req->len = 0;
 818                 scat_req->scat_entries = 0;
 819
 820                 status = ath6kl_htc_tx_setup_scat_list(target, endpoint,
 821                                                        scat_req, n_scat,
 822                                                        queue);
 823                 if (status == -EAGAIN) {
 824                         hif_scatter_req_add(target->dev->ar, scat_req);
 825                         break;
 826                 }
 827
 828                 /* send path is always asynchronous */
 829                 scat_req->complete = htc_async_tx_scat_complete;
 830                 n_sent_bundle++;
 831                 tot_pkts_bundle += scat_req->scat_entries;
 832
 833                 ath6kl_dbg(ATH6KL_DBG_HTC,
 834                            "htc tx scatter bytes %d entries %d\n",
 835                            scat_req->len, scat_req->scat_entries);
 836
 837                 for (i = 0; i < scat_req->scat_entries; i++) {
 838                         packet = scat_req->scat_list[i].packet;
 839                         trace_ath6kl_htc_tx(packet->status, packet->endpoint,
 840                                             packet->buf, packet->act_len);
 841                 }
 842
 843                 ath6kl_hif_submit_scat_req(target->dev, scat_req, false);
 844
 845                 if (status)
 846                         break;
 847         }
 848
 849         *sent_bundle = n_sent_bundle;
 850         *n_bundle_pkts = tot_pkts_bundle;
 851         ath6kl_dbg(ATH6KL_DBG_HTC, "htc tx bundle sent %d pkts\n",
 852                    n_sent_bundle);
 853
 854         return;
 855 }
 856
 857 static void ath6kl_htc_tx_from_queue(struct htc_target *target,
 858                                      struct htc_endpoint *endpoint)
 859 {
 860         struct list_head txq;
 861         struct htc_packet *packet;
 862         int bundle_sent;
 863         int n_pkts_bundle;
 864         u8 ac = WMM_NUM_AC;
 865         int status;
 866
 867         spin_lock_bh(&target->tx_lock);
 868
 869         endpoint->tx_proc_cnt++;
 870         if (endpoint->tx_proc_cnt > 1) {
 871                 endpoint->tx_proc_cnt--;
 872                 spin_unlock_bh(&target->tx_lock);
 873                 ath6kl_dbg(ATH6KL_DBG_HTC, "htc tx busy\n");
 874                 return;
 875         }
 876
 877         /*
 878          * drain the endpoint TX queue for transmission as long
 879          * as we have enough credits.
 880          */
 881         INIT_LIST_HEAD(&txq);
 882
 883         if ((HTC_CTRL_RSVD_SVC != endpoint->svc_id) &&
 884             (WMI_CONTROL_SVC != endpoint->svc_id))
 885                 ac = target->dev->ar->ep2ac_map[endpoint->eid];
 886
 887         while (true) {
 888                 if (list_empty(&endpoint->txq))
 889                         break;
 890
 891                 ath6kl_htc_tx_pkts_get(target, endpoint, &txq);
 892
 893                 if (list_empty(&txq))
 894                         break;
 895
 896                 spin_unlock_bh(&target->tx_lock);
 897
 898                 bundle_sent = 0;
 899                 n_pkts_bundle = 0;
 900
 901                 while (true) {
 902                         /* try to send a bundle on each pass */
 903                         if ((target->tx_bndl_mask) &&
 904                             (get_queue_depth(&txq) >=
 905                             HTC_MIN_HTC_MSGS_TO_BUNDLE)) {
 906                                 int temp1 = 0, temp2 = 0;
 907
 908                                 /* check if bundling is enabled for an AC */
 909                                 if (target->tx_bndl_mask & (1 << ac)) {
 910                                         ath6kl_htc_tx_bundle(endpoint, &txq,
 911                                                              &temp1, &temp2);
 912                                         bundle_sent += temp1;
 913                                         n_pkts_bundle += temp2;
 914                                 }
 915                         }
 916
 917                         if (list_empty(&txq))
 918                                 break;
 919
 920                         packet = list_first_entry(&txq, struct htc_packet,
 921                                                   list);
 922                         list_del(&packet->list);
 923
 924                         ath6kl_htc_tx_prep_pkt(packet, packet->info.tx.flags,
 925                                                0, packet->info.tx.seqno);
 926                         status = ath6kl_htc_tx_issue(target, packet);
 927
 928                         if (status) {
 929                                 packet->status = status;
 930                                 packet->completion(packet->context, packet);
 931                         }
 932                 }
 933
 934                 spin_lock_bh(&target->tx_lock);
 935
 936                 endpoint->ep_st.tx_bundles += bundle_sent;
 937                 endpoint->ep_st.tx_pkt_bundled += n_pkts_bundle;
 938
 939                 /*
 940                  * if an AC has bundling disabled and no tx bundling
 941                  * has occured continously for a certain number of TX,
 942                  * enable tx bundling for this AC
 943                  */
 944                 if (!bundle_sent) {
 945                         if (!(target->tx_bndl_mask & (1 << ac)) &&
 946                             (ac < WMM_NUM_AC)) {
 947                                 if (++target->ac_tx_count[ac] >=
 948                                         TX_RESUME_BUNDLE_THRESHOLD) {
 949                                         target->ac_tx_count[ac] = 0;
 950                                         target->tx_bndl_mask |= (1 << ac);
 951                                 }
 952                         }
 953                 } else {
 954                         /* tx bundling will reset the counter */
 955                         if (ac < WMM_NUM_AC)
 956                                 target->ac_tx_count[ac] = 0;
 957                 }
 958         }
 959
 960         endpoint->tx_proc_cnt = 0;
 961         spin_unlock_bh(&target->tx_lock);
 962 }
 963
 964 static bool ath6kl_htc_tx_try(struct htc_target *target,
 965                               struct htc_endpoint *endpoint,
 966                               struct htc_packet *tx_pkt)
 967 {
 968         struct htc_ep_callbacks ep_cb;
 969         int txq_depth;
 970         bool overflow = false;
 971
 972         ep_cb = endpoint->ep_cb;
 973
 974         spin_lock_bh(&target->tx_lock);
 975         txq_depth = get_queue_depth(&endpoint->txq);
 976         spin_unlock_bh(&target->tx_lock);
 977
 978         if (txq_depth >= endpoint->max_txq_depth)
 979                 overflow = true;
 980
 981         if (overflow)
 982                 ath6kl_dbg(ATH6KL_DBG_HTC,
 983                            "htc tx overflow ep %d depth %d max %d\n",
 984                            endpoint->eid, txq_depth,
 985                            endpoint->max_txq_depth);
 986
 987         if (overflow && ep_cb.tx_full) {
 988                 if (ep_cb.tx_full(endpoint->target, tx_pkt) ==
 989                     HTC_SEND_FULL_DROP) {
 990                         endpoint->ep_st.tx_dropped += 1;
 991                         return false;
 992                 }
 993         }
 994
 995         spin_lock_bh(&target->tx_lock);
 996         list_add_tail(&tx_pkt->list, &endpoint->txq);
 997         spin_unlock_bh(&target->tx_lock);
 998
 999         ath6kl_htc_tx_from_queue(target, endpoint);
1000
1001         return true;
1002 }
1003
1004 static void htc_chk_ep_txq(struct htc_target *target)
1005 {
1006         struct htc_endpoint *endpoint;
1007         struct htc_endpoint_credit_dist *cred_dist;
1008
1009         /*
1010          * Run through the credit distribution list to see if there are
1011          * packets queued. NOTE: no locks need to be taken since the
1012          * distribution list is not dynamic (cannot be re-ordered) and we
1013          * are not modifying any state.
1014          */
1015         list_for_each_entry(cred_dist, &target->cred_dist_list, list) {
1016                 endpoint = cred_dist->htc_ep;
1017
1018                 spin_lock_bh(&target->tx_lock);
1019                 if (!list_empty(&endpoint->txq)) {
1020                         ath6kl_dbg(ATH6KL_DBG_HTC,
1021                                    "htc creds ep %d credits %d pkts %d\n",
1022                                    cred_dist->endpoint,
1023                                    endpoint->cred_dist.credits,
1024                                    get_queue_depth(&endpoint->txq));
1025                         spin_unlock_bh(&target->tx_lock);
1026                         /*
1027                          * Try to start the stalled queue, this list is
1028                          * ordered by priority. If there are credits
1029                          * available the highest priority queue will get a
1030                          * chance to reclaim credits from lower priority
1031                          * ones.
1032                          */
1033                         ath6kl_htc_tx_from_queue(target, endpoint);
1034                         spin_lock_bh(&target->tx_lock);
1035                 }
1036                 spin_unlock_bh(&target->tx_lock);
1037         }
1038 }
1039
1040 static int htc_setup_tx_complete(struct htc_target *target)
1041 {
1042         struct htc_packet *send_pkt = NULL;
1043         int status;
1044
1045         send_pkt = htc_get_control_buf(target, true);
1046
1047         if (!send_pkt)
1048                 return -ENOMEM;
1049
1050         if (target->htc_tgt_ver >= HTC_VERSION_2P1) {
1051                 struct htc_setup_comp_ext_msg *setup_comp_ext;
1052                 u32 flags = 0;
1053
1054                 setup_comp_ext =
1055                     (struct htc_setup_comp_ext_msg *)send_pkt->buf;
1056                 memset(setup_comp_ext, 0, sizeof(*setup_comp_ext));
1057                 setup_comp_ext->msg_id =
1058                         cpu_to_le16(HTC_MSG_SETUP_COMPLETE_EX_ID);
1059
1060                 if (target->msg_per_bndl_max > 0) {
1061                         /* Indicate HTC bundling to the target */
1062                         flags |= HTC_SETUP_COMP_FLG_RX_BNDL_EN;
1063                         setup_comp_ext->msg_per_rxbndl =
1064                                                 target->msg_per_bndl_max;
1065                 }
1066
1067                 memcpy(&setup_comp_ext->flags, &flags,
1068                        sizeof(setup_comp_ext->flags));
1069                 set_htc_pkt_info(send_pkt, NULL, (u8 *) setup_comp_ext,
1070                                  sizeof(struct htc_setup_comp_ext_msg),
1071                                  ENDPOINT_0, HTC_SERVICE_TX_PACKET_TAG);
1072
1073         } else {
1074                 struct htc_setup_comp_msg *setup_comp;
1075                 setup_comp = (struct htc_setup_comp_msg *)send_pkt->buf;
1076                 memset(setup_comp, 0, sizeof(struct htc_setup_comp_msg));
1077                 setup_comp->msg_id = cpu_to_le16(HTC_MSG_SETUP_COMPLETE_ID);
1078                 set_htc_pkt_info(send_pkt, NULL, (u8 *) setup_comp,
1079                                  sizeof(struct htc_setup_comp_msg),
1080                                  ENDPOINT_0, HTC_SERVICE_TX_PACKET_TAG);
1081         }
1082
1083         /* we want synchronous operation */
1084         send_pkt->completion = NULL;
1085         ath6kl_htc_tx_prep_pkt(send_pkt, 0, 0, 0);
1086         status = ath6kl_htc_tx_issue(target, send_pkt);
1087         htc_reclaim_txctrl_buf(target, send_pkt);
1088
1089         return status;
1090 }
1091
1092 static void ath6kl_htc_set_credit_dist(struct htc_target *target,
1093                                 struct ath6kl_htc_credit_info *credit_info,
1094                                 u16 srvc_pri_order[], int list_len)
1095 {
1096         struct htc_endpoint *endpoint;
1097         int i, ep;
1098
1099         target->credit_info = credit_info;
1100
1101         list_add_tail(&target->endpoint[ENDPOINT_0].cred_dist.list,
1102                       &target->cred_dist_list);
1103
1104         for (i = 0; i < list_len; i++) {
1105                 for (ep = ENDPOINT_1; ep < ENDPOINT_MAX; ep++) {
1106                         endpoint = &target->endpoint[ep];
1107                         if (endpoint->svc_id == srvc_pri_order[i]) {
1108                                 list_add_tail(&endpoint->cred_dist.list,
1109                                               &target->cred_dist_list);
1110                                 break;
1111                         }
1112                 }
1113                 if (ep >= ENDPOINT_MAX) {
1114                         WARN_ON(1);
1115                         return;
1116                 }
1117         }
1118 }
1119
1120 static int ath6kl_htc_mbox_tx(struct htc_target *target,
1121                               struct htc_packet *packet)
1122 {
1123         struct htc_endpoint *endpoint;
1124         struct list_head queue;
1125
1126         ath6kl_dbg(ATH6KL_DBG_HTC,
1127                    "htc tx ep id %d buf 0x%p len %d\n",
1128                    packet->endpoint, packet->buf, packet->act_len);
1129
1130         if (packet->endpoint >= ENDPOINT_MAX) {
1131                 WARN_ON(1);
1132                 return -EINVAL;
1133         }
1134
1135         endpoint = &target->endpoint[packet->endpoint];
1136
1137         if (!ath6kl_htc_tx_try(target, endpoint, packet)) {
1138                 packet->status = (target->htc_flags & HTC_OP_STATE_STOPPING) ?
1139                                  -ECANCELED : -ENOSPC;
1140                 INIT_LIST_HEAD(&queue);
1141                 list_add(&packet->list, &queue);
1142                 htc_tx_complete(endpoint, &queue);
1143         }
1144
1145         return 0;
1146 }
1147
1148 /* flush endpoint TX queue */
1149 static void ath6kl_htc_mbox_flush_txep(struct htc_target *target,
1150                            enum htc_endpoint_id eid, u16 tag)
1151 {
1152         struct htc_packet *packet, *tmp_pkt;
1153         struct list_head discard_q, container;
1154         struct htc_endpoint *endpoint = &target->endpoint[eid];
1155
1156         if (!endpoint->svc_id) {
1157                 WARN_ON(1);
1158                 return;
1159         }
1160
1161         /* initialize the discard queue */
1162         INIT_LIST_HEAD(&discard_q);
1163
1164         spin_lock_bh(&target->tx_lock);
1165
1166         list_for_each_entry_safe(packet, tmp_pkt, &endpoint->txq, list) {
1167                 if ((tag == HTC_TX_PACKET_TAG_ALL) ||
1168                     (tag == packet->info.tx.tag))
1169                         list_move_tail(&packet->list, &discard_q);
1170         }
1171
1172         spin_unlock_bh(&target->tx_lock);
1173
1174         list_for_each_entry_safe(packet, tmp_pkt, &discard_q, list) {
1175                 packet->status = -ECANCELED;
1176                 list_del(&packet->list);
1177                 ath6kl_dbg(ATH6KL_DBG_HTC,
1178                            "htc tx flushing pkt 0x%p len %d  ep %d tag 0x%x\n",
1179                            packet, packet->act_len,
1180                            packet->endpoint, packet->info.tx.tag);
1181
1182                 INIT_LIST_HEAD(&container);
1183                 list_add_tail(&packet->list, &container);
1184                 htc_tx_complete(endpoint, &container);
1185         }
1186 }
1187
1188 static void ath6kl_htc_flush_txep_all(struct htc_target *target)
1189 {
1190         struct htc_endpoint *endpoint;
1191         int i;
1192
1193         dump_cred_dist_stats(target);
1194
1195         for (i = ENDPOINT_0; i < ENDPOINT_MAX; i++) {
1196                 endpoint = &target->endpoint[i];
1197                 if (endpoint->svc_id == 0)
1198                         /* not in use.. */
1199                         continue;
1200                 ath6kl_htc_mbox_flush_txep(target, i, HTC_TX_PACKET_TAG_ALL);
1201         }
1202 }
1203
1204 static void ath6kl_htc_mbox_activity_changed(struct htc_target *target,
1205                                              enum htc_endpoint_id eid,
1206                                              bool active)
1207 {
1208         struct htc_endpoint *endpoint = &target->endpoint[eid];
1209         bool dist = false;
1210
1211         if (endpoint->svc_id == 0) {
1212                 WARN_ON(1);
1213                 return;
1214         }
1215
1216         spin_lock_bh(&target->tx_lock);
1217
1218         if (active) {
1219                 if (!(endpoint->cred_dist.dist_flags & HTC_EP_ACTIVE)) {
1220                         endpoint->cred_dist.dist_flags |= HTC_EP_ACTIVE;
1221                         dist = true;
1222                 }
1223         } else {
1224                 if (endpoint->cred_dist.dist_flags & HTC_EP_ACTIVE) {
1225                         endpoint->cred_dist.dist_flags &= ~HTC_EP_ACTIVE;
1226                         dist = true;
1227                 }
1228         }
1229
1230         if (dist) {
1231                 endpoint->cred_dist.txq_depth =
1232                         get_queue_depth(&endpoint->txq);
1233
1234                 ath6kl_dbg(ATH6KL_DBG_HTC,
1235                            "htc tx activity ctxt 0x%p dist 0x%p\n",
1236                            target->credit_info, &target->cred_dist_list);
1237
1238                 ath6kl_credit_distribute(target->credit_info,
1239                                          &target->cred_dist_list,
1240                                          HTC_CREDIT_DIST_ACTIVITY_CHANGE);
1241         }
1242
1243         spin_unlock_bh(&target->tx_lock);
1244
1245         if (dist && !active)
1246                 htc_chk_ep_txq(target);
1247 }
1248
1249 /* HTC Rx */
1250
1251 static inline void ath6kl_htc_rx_update_stats(struct htc_endpoint *endpoint,
1252                                               int n_look_ahds)
1253 {
1254         endpoint->ep_st.rx_pkts++;
1255         if (n_look_ahds == 1)
1256                 endpoint->ep_st.rx_lkahds++;
1257         else if (n_look_ahds > 1)
1258                 endpoint->ep_st.rx_bundle_lkahd++;
1259 }
1260
1261 static inline bool htc_valid_rx_frame_len(struct htc_target *target,
1262                                           enum htc_endpoint_id eid, int len)
1263 {
1264         return (eid == target->dev->ar->ctrl_ep) ?
1265                 len <= ATH6KL_BUFFER_SIZE : len <= ATH6KL_AMSDU_BUFFER_SIZE;
1266 }
1267
1268 static int htc_add_rxbuf(struct htc_target *target, struct htc_packet *packet)
1269 {
1270         struct list_head queue;
1271
1272         INIT_LIST_HEAD(&queue);
1273         list_add_tail(&packet->list, &queue);
1274         return ath6kl_htc_mbox_add_rxbuf_multiple(target, &queue);
1275 }
1276
1277 static void htc_reclaim_rxbuf(struct htc_target *target,
1278                               struct htc_packet *packet,
1279                               struct htc_endpoint *ep)
1280 {
1281         if (packet->info.rx.rx_flags & HTC_RX_PKT_NO_RECYCLE) {
1282                 htc_rxpkt_reset(packet);
1283                 packet->status = -ECANCELED;
1284                 ep->ep_cb.rx(ep->target, packet);
1285         } else {
1286                 htc_rxpkt_reset(packet);
1287                 htc_add_rxbuf((void *)(target), packet);
1288         }
1289 }
1290
1291 static void reclaim_rx_ctrl_buf(struct htc_target *target,
1292                                 struct htc_packet *packet)
1293 {
1294         spin_lock_bh(&target->htc_lock);
1295         list_add_tail(&packet->list, &target->free_ctrl_rxbuf);
1296         spin_unlock_bh(&target->htc_lock);
1297 }
1298
1299 static int ath6kl_htc_rx_packet(struct htc_target *target,
1300                                 struct htc_packet *packet,
1301                                 u32 rx_len)
1302 {
1303         struct ath6kl_device *dev = target->dev;
1304         u32 padded_len;
1305         int status;
1306
1307         padded_len = CALC_TXRX_PADDED_LEN(target, rx_len);
1308
1309         if (padded_len > packet->buf_len) {
1310                 ath6kl_err("not enough receive space for packet - padlen %d recvlen %d bufferlen %d\n",
1311                            padded_len, rx_len, packet->buf_len);
1312                 return -ENOMEM;
1313         }
1314
1315         ath6kl_dbg(ATH6KL_DBG_HTC,
1316                    "htc rx 0x%p hdr 0x%x len %d mbox 0x%x\n",
1317                    packet, packet->info.rx.exp_hdr,
1318                    padded_len, dev->ar->mbox_info.htc_addr);
1319
1320         status = hif_read_write_sync(dev->ar,
1321                                      dev->ar->mbox_info.htc_addr,
1322                                      packet->buf, padded_len,
1323                                      HIF_RD_SYNC_BLOCK_FIX);
1324
1325         packet->status = status;
1326
1327         return status;
1328 }
1329
1330 /*
1331  * optimization for recv packets, we can indicate a
1332  * "hint" that there are more  single-packets to fetch
1333  * on this endpoint.
1334  */
1335 static void ath6kl_htc_rx_set_indicate(u32 lk_ahd,
1336                                        struct htc_endpoint *endpoint,
1337                                        struct htc_packet *packet)
1338 {
1339         struct htc_frame_hdr *htc_hdr = (struct htc_frame_hdr *)&lk_ahd;
1340
1341         if (htc_hdr->eid == packet->endpoint) {
1342                 if (!list_empty(&endpoint->rx_bufq))
1343                         packet->info.rx.indicat_flags |=
1344                                         HTC_RX_FLAGS_INDICATE_MORE_PKTS;
1345         }
1346 }
1347
1348 static void ath6kl_htc_rx_chk_water_mark(struct htc_endpoint *endpoint)
1349 {
1350         struct htc_ep_callbacks ep_cb = endpoint->ep_cb;
1351
1352         if (ep_cb.rx_refill_thresh > 0) {
1353                 spin_lock_bh(&endpoint->target->rx_lock);
1354                 if (get_queue_depth(&endpoint->rx_bufq)
1355                     < ep_cb.rx_refill_thresh) {
1356                         spin_unlock_bh(&endpoint->target->rx_lock);
1357                         ep_cb.rx_refill(endpoint->target, endpoint->eid);
1358                         return;
1359                 }
1360                 spin_unlock_bh(&endpoint->target->rx_lock);
1361         }
1362 }
1363
1364 /* This function is called with rx_lock held */
1365 static int ath6kl_htc_rx_setup(struct htc_target *target,
1366                                struct htc_endpoint *ep,
1367                                u32 *lk_ahds, struct list_head *queue, int n_msg)
1368 {
1369         struct htc_packet *packet;
1370         /* FIXME: type of lk_ahds can't be right */
1371         struct htc_frame_hdr *htc_hdr = (struct htc_frame_hdr *)lk_ahds;
1372         struct htc_ep_callbacks ep_cb;
1373         int status = 0, j, full_len;
1374         bool no_recycle;
1375
1376         full_len = CALC_TXRX_PADDED_LEN(target,
1377                                         le16_to_cpu(htc_hdr->payld_len) +
1378                                         sizeof(*htc_hdr));
1379
1380         if (!htc_valid_rx_frame_len(target, ep->eid, full_len)) {
1381                 ath6kl_warn("Rx buffer requested with invalid length htc_hdr:eid %d, flags 0x%x, len %d\n",
1382                             htc_hdr->eid, htc_hdr->flags,
1383                             le16_to_cpu(htc_hdr->payld_len));
1384                 return -EINVAL;
1385         }
1386
1387         ep_cb = ep->ep_cb;
1388         for (j = 0; j < n_msg; j++) {
1389                 /*
1390                  * Reset flag, any packets allocated using the
1391                  * rx_alloc() API cannot be recycled on
1392                  * cleanup,they must be explicitly returned.
1393                  */
1394                 no_recycle = false;
1395
1396                 if (ep_cb.rx_allocthresh &&
1397                     (full_len > ep_cb.rx_alloc_thresh)) {
1398                         ep->ep_st.rx_alloc_thresh_hit += 1;
1399                         ep->ep_st.rxalloc_thresh_byte +=
1400                                 le16_to_cpu(htc_hdr->payld_len);
1401
1402                         spin_unlock_bh(&target->rx_lock);
1403                         no_recycle = true;
1404
1405                         packet = ep_cb.rx_allocthresh(ep->target, ep->eid,
1406                                                       full_len);
1407                         spin_lock_bh(&target->rx_lock);
1408                 } else {
1409                         /* refill handler is being used */
1410                         if (list_empty(&ep->rx_bufq)) {
1411                                 if (ep_cb.rx_refill) {
1412                                         spin_unlock_bh(&target->rx_lock);
1413                                         ep_cb.rx_refill(ep->target, ep->eid);
1414                                         spin_lock_bh(&target->rx_lock);
1415                                 }
1416                         }
1417
1418                         if (list_empty(&ep->rx_bufq)) {
1419                                 packet = NULL;
1420                         } else {
1421                                 packet = list_first_entry(&ep->rx_bufq,
1422                                                 struct htc_packet, list);
1423                                 list_del(&packet->list);
1424                         }
1425                 }
1426
1427                 if (!packet) {
1428                         target->rx_st_flags |= HTC_RECV_WAIT_BUFFERS;
1429                         target->ep_waiting = ep->eid;
1430                         return -ENOSPC;
1431                 }
1432
1433                 /* clear flags */
1434                 packet->info.rx.rx_flags = 0;
1435                 packet->info.rx.indicat_flags = 0;
1436                 packet->status = 0;
1437
1438                 if (no_recycle)
1439                         /*
1440                          * flag that these packets cannot be
1441                          * recycled, they have to be returned to
1442                          * the user
1443                          */
1444                         packet->info.rx.rx_flags |= HTC_RX_PKT_NO_RECYCLE;
1445
1446                 /* Caller needs to free this upon any failure */
1447                 list_add_tail(&packet->list, queue);
1448
1449                 if (target->htc_flags & HTC_OP_STATE_STOPPING) {
1450                         status = -ECANCELED;
1451                         break;
1452                 }
1453
1454                 if (j) {
1455                         packet->info.rx.rx_flags |= HTC_RX_PKT_REFRESH_HDR;
1456                         packet->info.rx.exp_hdr = 0xFFFFFFFF;
1457                 } else
1458                         /* set expected look ahead */
1459                         packet->info.rx.exp_hdr = *lk_ahds;
1460
1461                 packet->act_len = le16_to_cpu(htc_hdr->payld_len) +
1462                         HTC_HDR_LENGTH;
1463         }
1464
1465         return status;
1466 }
1467
1468 static int ath6kl_htc_rx_alloc(struct htc_target *target,
1469                                u32 lk_ahds[], int msg,
1470                                struct htc_endpoint *endpoint,
1471                                struct list_head *queue)
1472 {
1473         int status = 0;
1474         struct htc_packet *packet, *tmp_pkt;
1475         struct htc_frame_hdr *htc_hdr;
1476         int i, n_msg;
1477
1478         spin_lock_bh(&target->rx_lock);
1479
1480         for (i = 0; i < msg; i++) {
1481                 htc_hdr = (struct htc_frame_hdr *)&lk_ahds[i];
1482
1483                 if (htc_hdr->eid >= ENDPOINT_MAX) {
1484                         ath6kl_err("invalid ep in look-ahead: %d\n",
1485                                    htc_hdr->eid);
1486                         status = -ENOMEM;
1487                         break;
1488                 }
1489
1490                 if (htc_hdr->eid != endpoint->eid) {
1491                         ath6kl_err("invalid ep in look-ahead: %d should be : %d (index:%d)\n",
1492                                    htc_hdr->eid, endpoint->eid, i);
1493                         status = -ENOMEM;
1494                         break;
1495                 }
1496
1497                 if (le16_to_cpu(htc_hdr->payld_len) > HTC_MAX_PAYLOAD_LENGTH) {
1498                         ath6kl_err("payload len %d exceeds max htc : %d !\n",
1499                                    htc_hdr->payld_len,
1500                                    (u32) HTC_MAX_PAYLOAD_LENGTH);
1501                         status = -ENOMEM;
1502                         break;
1503                 }
1504
1505                 if (endpoint->svc_id == 0) {
1506                         ath6kl_err("ep %d is not connected !\n", htc_hdr->eid);
1507                         status = -ENOMEM;
1508                         break;
1509                 }
1510
1511                 if (htc_hdr->flags & HTC_FLG_RX_BNDL_CNT) {
1512                         /*
1513                          * HTC header indicates that every packet to follow
1514                          * has the same padded length so that it can be
1515                          * optimally fetched as a full bundle.
1516                          */
1517                         n_msg = (htc_hdr->flags & HTC_FLG_RX_BNDL_CNT) >>
1518                                 HTC_FLG_RX_BNDL_CNT_S;
1519
1520                         /* the count doesn't include the starter frame */
1521                         n_msg++;
1522                         if (n_msg > target->msg_per_bndl_max) {
1523                                 status = -ENOMEM;
1524                                 break;
1525                         }
1526
1527                         endpoint->ep_st.rx_bundle_from_hdr += 1;
1528                         ath6kl_dbg(ATH6KL_DBG_HTC,
1529                                    "htc rx bundle pkts %d\n",
1530                                    n_msg);
1531                 } else
1532                         /* HTC header only indicates 1 message to fetch */
1533                         n_msg = 1;
1534
1535                 /* Setup packet buffers for each message */
1536                 status = ath6kl_htc_rx_setup(target, endpoint, &lk_ahds[i],
1537                                              queue, n_msg);
1538
1539                 /*
1540                  * This is due to unavailability of buffers to rx entire data.
1541                  * Return no error so that free buffers from queue can be used
1542                  * to receive partial data.
1543                  */
1544                 if (status == -ENOSPC) {
1545                         spin_unlock_bh(&target->rx_lock);
1546                         return 0;
1547                 }
1548
1549                 if (status)
1550                         break;
1551         }
1552
1553         spin_unlock_bh(&target->rx_lock);
1554
1555         if (status) {
1556                 list_for_each_entry_safe(packet, tmp_pkt, queue, list) {
1557                         list_del(&packet->list);
1558                         htc_reclaim_rxbuf(target, packet,
1559                                           &target->endpoint[packet->endpoint]);
1560                 }
1561         }
1562
1563         return status;
1564 }
1565
1566 static void htc_ctrl_rx(struct htc_target *context, struct htc_packet *packets)
1567 {
1568         if (packets->endpoint != ENDPOINT_0) {
1569                 WARN_ON(1);
1570                 return;
1571         }
1572
1573         if (packets->status == -ECANCELED) {
1574                 reclaim_rx_ctrl_buf(context, packets);
1575                 return;
1576         }
1577
1578         if (packets->act_len > 0) {
1579                 ath6kl_err("htc_ctrl_rx, got message with len:%zu\n",
1580                            packets->act_len + HTC_HDR_LENGTH);
1581
1582                 ath6kl_dbg_dump(ATH6KL_DBG_HTC,
1583                                 "htc rx unexpected endpoint 0 message", "",
1584                                 packets->buf - HTC_HDR_LENGTH,
1585                                 packets->act_len + HTC_HDR_LENGTH);
1586         }
1587
1588         htc_reclaim_rxbuf(context, packets, &context->endpoint[0]);
1589 }
1590
1591 static void htc_proc_cred_rpt(struct htc_target *target,
1592                               struct htc_credit_report *rpt,
1593                               int n_entries,
1594                               enum htc_endpoint_id from_ep)
1595 {
1596         struct htc_endpoint *endpoint;
1597         int tot_credits = 0, i;
1598         bool dist = false;
1599
1600         spin_lock_bh(&target->tx_lock);
1601
1602         for (i = 0; i < n_entries; i++, rpt++) {
1603                 if (rpt->eid >= ENDPOINT_MAX) {
1604                         WARN_ON(1);
1605                         spin_unlock_bh(&target->tx_lock);
1606                         return;
1607                 }
1608
1609                 endpoint = &target->endpoint[rpt->eid];
1610
1611                 ath6kl_dbg(ATH6KL_DBG_CREDIT,
1612                            "credit report ep %d credits %d\n",
1613                            rpt->eid, rpt->credits);
1614
1615                 endpoint->ep_st.tx_cred_rpt += 1;
1616                 endpoint->ep_st.cred_retnd += rpt->credits;
1617
1618                 if (from_ep == rpt->eid) {
1619                         /*
1620                          * This credit report arrived on the same endpoint
1621                          * indicating it arrived in an RX packet.
1622                          */
1623                         endpoint->ep_st.cred_from_rx += rpt->credits;
1624                         endpoint->ep_st.cred_rpt_from_rx += 1;
1625                 } else if (from_ep == ENDPOINT_0) {
1626                         /* credit arrived on endpoint 0 as a NULL message */
1627                         endpoint->ep_st.cred_from_ep0 += rpt->credits;
1628                         endpoint->ep_st.cred_rpt_ep0 += 1;
1629                 } else {
1630                         endpoint->ep_st.cred_from_other += rpt->credits;
1631                         endpoint->ep_st.cred_rpt_from_other += 1;
1632                 }
1633
1634                 if (rpt->eid == ENDPOINT_0)
1635                         /* always give endpoint 0 credits back */
1636                         endpoint->cred_dist.credits += rpt->credits;
1637                 else {
1638                         endpoint->cred_dist.cred_to_dist += rpt->credits;
1639                         dist = true;
1640                 }
1641
1642                 /*
1643                  * Refresh tx depth for distribution function that will
1644                  * recover these credits NOTE: this is only valid when
1645                  * there are credits to recover!
1646                  */
1647                 endpoint->cred_dist.txq_depth =
1648                         get_queue_depth(&endpoint->txq);
1649
1650                 tot_credits += rpt->credits;
1651         }
1652
1653         if (dist) {
1654                 /*
1655                  * This was a credit return based on a completed send
1656                  * operations note, this is done with the lock held
1657                  */
1658                 ath6kl_credit_distribute(target->credit_info,
1659                                          &target->cred_dist_list,
1660                                          HTC_CREDIT_DIST_SEND_COMPLETE);
1661         }
1662
1663         spin_unlock_bh(&target->tx_lock);
1664
1665         if (tot_credits)
1666                 htc_chk_ep_txq(target);
1667 }
1668
1669 static int htc_parse_trailer(struct htc_target *target,
1670                              struct htc_record_hdr *record,
1671                              u8 *record_buf, u32 *next_lk_ahds,
1672                              enum htc_endpoint_id endpoint,
1673                              int *n_lk_ahds)
1674 {
1675         struct htc_bundle_lkahd_rpt *bundle_lkahd_rpt;
1676         struct htc_lookahead_report *lk_ahd;
1677         int len;
1678
1679         switch (record->rec_id) {
1680         case HTC_RECORD_CREDITS:
1681                 len = record->len / sizeof(struct htc_credit_report);
1682                 if (!len) {
1683                         WARN_ON(1);
1684                         return -EINVAL;
1685                 }
1686
1687                 htc_proc_cred_rpt(target,
1688                                   (struct htc_credit_report *) record_buf,
1689                                   len, endpoint);
1690                 break;
1691         case HTC_RECORD_LOOKAHEAD:
1692                 len = record->len / sizeof(*lk_ahd);
1693                 if (!len) {
1694                         WARN_ON(1);
1695                         return -EINVAL;
1696                 }
1697
1698                 lk_ahd = (struct htc_lookahead_report *) record_buf;
1699                 if ((lk_ahd->pre_valid == ((~lk_ahd->post_valid) & 0xFF)) &&
1700                     next_lk_ahds) {
1701                         ath6kl_dbg(ATH6KL_DBG_HTC,
1702                                    "htc rx lk_ahd found pre_valid 0x%x post_valid 0x%x\n",
1703                                    lk_ahd->pre_valid, lk_ahd->post_valid);
1704
1705                         /* look ahead bytes are valid, copy them over */
1706                         memcpy((u8 *)&next_lk_ahds[0], lk_ahd->lk_ahd, 4);
1707
1708                         ath6kl_dbg_dump(ATH6KL_DBG_HTC,
1709                                         "htc rx next look ahead",
1710                                         "", next_lk_ahds, 4);
1711
1712                         *n_lk_ahds = 1;
1713                 }
1714                 break;
1715         case HTC_RECORD_LOOKAHEAD_BUNDLE:
1716                 len = record->len / sizeof(*bundle_lkahd_rpt);
1717                 if (!len || (len > HTC_HOST_MAX_MSG_PER_BUNDLE)) {
1718                         WARN_ON(1);
1719                         return -EINVAL;
1720                 }
1721
1722                 if (next_lk_ahds) {
1723                         int i;
1724
1725                         bundle_lkahd_rpt =
1726                                 (struct htc_bundle_lkahd_rpt *) record_buf;
1727
1728                         ath6kl_dbg_dump(ATH6KL_DBG_HTC, "htc rx bundle lk_ahd",
1729                                         "", record_buf, record->len);
1730
1731                         for (i = 0; i < len; i++) {
1732                                 memcpy((u8 *)&next_lk_ahds[i],
1733                                        bundle_lkahd_rpt->lk_ahd, 4);
1734                                 bundle_lkahd_rpt++;
1735                         }
1736
1737                         *n_lk_ahds = i;
1738                 }
1739                 break;
1740         default:
1741                 ath6kl_err("unhandled record: id:%d len:%d\n",
1742                            record->rec_id, record->len);
1743                 break;
1744         }
1745
1746         return 0;
1747 }
1748
1749 static int htc_proc_trailer(struct htc_target *target,
1750                             u8 *buf, int len, u32 *next_lk_ahds,
1751                             int *n_lk_ahds, enum htc_endpoint_id endpoint)
1752 {
1753         struct htc_record_hdr *record;
1754         int orig_len;
1755         int status;
1756         u8 *record_buf;
1757         u8 *orig_buf;
1758
1759         ath6kl_dbg(ATH6KL_DBG_HTC, "htc rx trailer len %d\n", len);
1760         ath6kl_dbg_dump(ATH6KL_DBG_HTC, NULL, "", buf, len);
1761
1762         orig_buf = buf;
1763         orig_len = len;
1764         status = 0;
1765
1766         while (len > 0) {
1767                 if (len < sizeof(struct htc_record_hdr)) {
1768                         status = -ENOMEM;
1769                         break;
1770                 }
1771                 /* these are byte aligned structs */
1772                 record = (struct htc_record_hdr *) buf;
1773                 len -= sizeof(struct htc_record_hdr);
1774                 buf += sizeof(struct htc_record_hdr);
1775
1776                 if (record->len > len) {
1777                         ath6kl_err("invalid record len: %d (id:%d) buf has: %d bytes left\n",
1778                                    record->len, record->rec_id, len);
1779                         status = -ENOMEM;
1780                         break;
1781                 }
1782                 record_buf = buf;
1783
1784                 status = htc_parse_trailer(target, record, record_buf,
1785                                            next_lk_ahds, endpoint, n_lk_ahds);
1786
1787                 if (status)
1788                         break;
1789
1790                 /* advance buffer past this record for next time around */
1791                 buf += record->len;
1792                 len -= record->len;
1793         }
1794
1795         if (status)
1796                 ath6kl_dbg_dump(ATH6KL_DBG_HTC, "htc rx bad trailer",
1797                                 "", orig_buf, orig_len);
1798
1799         return status;
1800 }
1801
1802 static int ath6kl_htc_rx_process_hdr(struct htc_target *target,
1803                                      struct htc_packet *packet,
1804                                      u32 *next_lkahds, int *n_lkahds)
1805 {
1806         int status = 0;
1807         u16 payload_len;
1808         u32 lk_ahd;
1809         struct htc_frame_hdr *htc_hdr = (struct htc_frame_hdr *)packet->buf;
1810
1811         if (n_lkahds != NULL)
1812                 *n_lkahds = 0;
1813
1814         /*
1815          * NOTE: we cannot assume the alignment of buf, so we use the safe
1816          * macros to retrieve 16 bit fields.
1817          */
1818         payload_len = le16_to_cpu(get_unaligned(&htc_hdr->payld_len));
1819
1820         memcpy((u8 *)&lk_ahd, packet->buf, sizeof(lk_ahd));
1821
1822         if (packet->info.rx.rx_flags & HTC_RX_PKT_REFRESH_HDR) {
1823                 /*
1824                  * Refresh the expected header and the actual length as it
1825                  * was unknown when this packet was grabbed as part of the
1826                  * bundle.
1827                  */
1828                 packet->info.rx.exp_hdr = lk_ahd;
1829                 packet->act_len = payload_len + HTC_HDR_LENGTH;
1830
1831                 /* validate the actual header that was refreshed  */
1832                 if (packet->act_len > packet->buf_len) {
1833                         ath6kl_err("refreshed hdr payload len (%d) in bundled recv is invalid (hdr: 0x%X)\n",
1834                                    payload_len, lk_ahd);
1835                         /*
1836                          * Limit this to max buffer just to print out some
1837                          * of the buffer.
1838                          */
1839                         packet->act_len = min(packet->act_len, packet->buf_len);
1840                         status = -ENOMEM;
1841                         goto fail_rx;
1842                 }
1843
1844                 if (packet->endpoint != htc_hdr->eid) {
1845                         ath6kl_err("refreshed hdr ep (%d) does not match expected ep (%d)\n",
1846                                    htc_hdr->eid, packet->endpoint);
1847                         status = -ENOMEM;
1848                         goto fail_rx;
1849                 }
1850         }
1851
1852         if (lk_ahd != packet->info.rx.exp_hdr) {
1853                 ath6kl_err("%s(): lk_ahd mismatch! (pPkt:0x%p flags:0x%X)\n",
1854                            __func__, packet, packet->info.rx.rx_flags);
1855                 ath6kl_dbg_dump(ATH6KL_DBG_HTC, "htc rx expected lk_ahd",
1856                                 "", &packet->info.rx.exp_hdr, 4);
1857                 ath6kl_dbg_dump(ATH6KL_DBG_HTC, "htc rx current header",
1858                                 "", (u8 *)&lk_ahd, sizeof(lk_ahd));
1859                 status = -ENOMEM;
1860                 goto fail_rx;
1861         }
1862
1863         if (htc_hdr->flags & HTC_FLG_RX_TRAILER) {
1864                 if (htc_hdr->ctrl[0] < sizeof(struct htc_record_hdr) ||
1865                     htc_hdr->ctrl[0] > payload_len) {
1866                         ath6kl_err("%s(): invalid hdr (payload len should be :%d, CB[0] is:%d)\n",
1867                                    __func__, payload_len, htc_hdr->ctrl[0]);
1868                         status = -ENOMEM;
1869                         goto fail_rx;
1870                 }
1871
1872                 if (packet->info.rx.rx_flags & HTC_RX_PKT_IGNORE_LOOKAHEAD) {
1873                         next_lkahds = NULL;
1874                         n_lkahds = NULL;
1875                 }
1876
1877                 status = htc_proc_trailer(target, packet->buf + HTC_HDR_LENGTH
1878                                           + payload_len - htc_hdr->ctrl[0],
1879                                           htc_hdr->ctrl[0], next_lkahds,
1880                                            n_lkahds, packet->endpoint);
1881
1882                 if (status)
1883                         goto fail_rx;
1884
1885                 packet->act_len -= htc_hdr->ctrl[0];
1886         }
1887
1888         packet->buf += HTC_HDR_LENGTH;
1889         packet->act_len -= HTC_HDR_LENGTH;
1890
1891 fail_rx:
1892         if (status)
1893                 ath6kl_dbg_dump(ATH6KL_DBG_HTC, "htc rx bad packet",
1894                                 "", packet->buf, packet->act_len);
1895
1896         return status;
1897 }
1898
1899 static void ath6kl_htc_rx_complete(struct htc_endpoint *endpoint,
1900                                    struct htc_packet *packet)
1901 {
1902                 ath6kl_dbg(ATH6KL_DBG_HTC,
1903                            "htc rx complete ep %d packet 0x%p\n",
1904                            endpoint->eid, packet);
1905
1906                 endpoint->ep_cb.rx(endpoint->target, packet);
1907 }
1908
1909 static int ath6kl_htc_rx_bundle(struct htc_target *target,
1910                                 struct list_head *rxq,
1911                                 struct list_head *sync_compq,
1912                                 int *n_pkt_fetched, bool part_bundle)
1913 {
1914         struct hif_scatter_req *scat_req;
1915         struct htc_packet *packet;
1916         int rem_space = target->max_rx_bndl_sz;
1917         int n_scat_pkt, status = 0, i, len;
1918
1919         n_scat_pkt = get_queue_depth(rxq);
1920         n_scat_pkt = min(n_scat_pkt, target->msg_per_bndl_max);
1921
1922         if ((get_queue_depth(rxq) - n_scat_pkt) > 0) {
1923                 /*
1924                  * We were forced to split this bundle receive operation
1925                  * all packets in this partial bundle must have their
1926                  * lookaheads ignored.
1927                  */
1928                 part_bundle = true;
1929
1930                 /*
1931                  * This would only happen if the target ignored our max
1932                  * bundle limit.
1933                  */
1934                 ath6kl_warn("%s(): partial bundle detected num:%d , %d\n",
1935                             __func__, get_queue_depth(rxq), n_scat_pkt);
1936         }
1937
1938         len = 0;
1939
1940         ath6kl_dbg(ATH6KL_DBG_HTC,
1941                    "htc rx bundle depth %d pkts %d\n",
1942                    get_queue_depth(rxq), n_scat_pkt);
1943
1944         scat_req = hif_scatter_req_get(target->dev->ar);
1945
1946         if (scat_req == NULL)
1947                 goto fail_rx_pkt;
1948
1949         for (i = 0; i < n_scat_pkt; i++) {
1950                 int pad_len;
1951
1952                 packet = list_first_entry(rxq, struct htc_packet, list);
1953                 list_del(&packet->list);
1954
1955                 pad_len = CALC_TXRX_PADDED_LEN(target,
1956                                                    packet->act_len);
1957
1958                 if ((rem_space - pad_len) < 0) {
1959                         list_add(&packet->list, rxq);
1960                         break;
1961                 }
1962
1963                 rem_space -= pad_len;
1964
1965                 if (part_bundle || (i < (n_scat_pkt - 1)))
1966                         /*
1967                          * Packet 0..n-1 cannot be checked for look-aheads
1968                          * since we are fetching a bundle the last packet
1969                          * however can have it's lookahead used
1970                          */
1971                         packet->info.rx.rx_flags |=
1972                             HTC_RX_PKT_IGNORE_LOOKAHEAD;
1973
1974                 /* NOTE: 1 HTC packet per scatter entry */
1975                 scat_req->scat_list[i].buf = packet->buf;
1976                 scat_req->scat_list[i].len = pad_len;
1977
1978                 packet->info.rx.rx_flags |= HTC_RX_PKT_PART_OF_BUNDLE;
1979
1980                 list_add_tail(&packet->list, sync_compq);
1981
1982                 WARN_ON(!scat_req->scat_list[i].len);
1983                 len += scat_req->scat_list[i].len;
1984         }
1985
1986         scat_req->len = len;
1987         scat_req->scat_entries = i;
1988
1989         status = ath6kl_hif_submit_scat_req(target->dev, scat_req, true);
1990
1991         if (!status)
1992                 *n_pkt_fetched = i;
1993
1994         /* free scatter request */
1995         hif_scatter_req_add(target->dev->ar, scat_req);
1996
1997 fail_rx_pkt:
1998
1999         return status;
2000 }
2001
2002 static int ath6kl_htc_rx_process_packets(struct htc_target *target,
2003                                          struct list_head *comp_pktq,
2004                                          u32 lk_ahds[],
2005                                          int *n_lk_ahd)
2006 {
2007         struct htc_packet *packet, *tmp_pkt;
2008         struct htc_endpoint *ep;
2009         int status = 0;
2010
2011         list_for_each_entry_safe(packet, tmp_pkt, comp_pktq, list) {
2012                 ep = &target->endpoint[packet->endpoint];
2013
2014                 trace_ath6kl_htc_rx(packet->status, packet->endpoint,
2015                                     packet->buf, packet->act_len);
2016
2017                 /* process header for each of the recv packet */
2018                 status = ath6kl_htc_rx_process_hdr(target, packet, lk_ahds,
2019                                                    n_lk_ahd);
2020                 if (status)
2021                         return status;
2022
2023                 list_del(&packet->list);
2024
2025                 if (list_empty(comp_pktq)) {
2026                         /*
2027                          * Last packet's more packet flag is set
2028                          * based on the lookahead.
2029                          */
2030                         if (*n_lk_ahd > 0)
2031                                 ath6kl_htc_rx_set_indicate(lk_ahds[0],
2032                                                            ep, packet);
2033                 } else
2034                         /*
2035                          * Packets in a bundle automatically have
2036                          * this flag set.
2037                          */
2038                         packet->info.rx.indicat_flags |=
2039                                 HTC_RX_FLAGS_INDICATE_MORE_PKTS;
2040
2041                 ath6kl_htc_rx_update_stats(ep, *n_lk_ahd);
2042
2043                 if (packet->info.rx.rx_flags & HTC_RX_PKT_PART_OF_BUNDLE)
2044                         ep->ep_st.rx_bundl += 1;
2045
2046                 ath6kl_htc_rx_complete(ep, packet);
2047         }
2048
2049         return status;
2050 }
2051
2052 static int ath6kl_htc_rx_fetch(struct htc_target *target,
2053                                struct list_head *rx_pktq,
2054                                struct list_head *comp_pktq)
2055 {
2056         int fetched_pkts;
2057         bool part_bundle = false;
2058         int status = 0;
2059         struct list_head tmp_rxq;
2060         struct htc_packet *packet, *tmp_pkt;
2061
2062         /* now go fetch the list of HTC packets */
2063         while (!list_empty(rx_pktq)) {
2064                 fetched_pkts = 0;
2065
2066                 INIT_LIST_HEAD(&tmp_rxq);
2067
2068                 if (target->rx_bndl_enable && (get_queue_depth(rx_pktq) > 1)) {
2069                         /*
2070                          * There are enough packets to attempt a
2071                          * bundle transfer and recv bundling is
2072                          * allowed.
2073                          */
2074                         status = ath6kl_htc_rx_bundle(target, rx_pktq,
2075                                                       &tmp_rxq,
2076                                                       &fetched_pkts,
2077                                                       part_bundle);
2078                         if (status)
2079                                 goto fail_rx;
2080
2081                         if (!list_empty(rx_pktq))
2082                                 part_bundle = true;
2083
2084                         list_splice_tail_init(&tmp_rxq, comp_pktq);
2085                 }
2086
2087                 if (!fetched_pkts) {
2088                         packet = list_first_entry(rx_pktq, struct htc_packet,
2089                                                    list);
2090
2091                         /* fully synchronous */
2092                         packet->completion = NULL;
2093
2094                         if (!list_is_singular(rx_pktq))
2095                                 /*
2096                                  * look_aheads in all packet
2097                                  * except the last one in the
2098                                  * bundle must be ignored
2099                                  */
2100                                 packet->info.rx.rx_flags |=
2101                                         HTC_RX_PKT_IGNORE_LOOKAHEAD;
2102
2103                         /* go fetch the packet */
2104                         status = ath6kl_htc_rx_packet(target, packet,
2105                                                       packet->act_len);
2106
2107                         list_move_tail(&packet->list, &tmp_rxq);
2108
2109                         if (status)
2110                                 goto fail_rx;
2111
2112                         list_splice_tail_init(&tmp_rxq, comp_pktq);
2113                 }
2114         }
2115
2116         return 0;
2117
2118 fail_rx:
2119
2120         /*
2121          * Cleanup any packets we allocated but didn't use to
2122          * actually fetch any packets.
2123          */
2124
2125         list_for_each_entry_safe(packet, tmp_pkt, rx_pktq, list) {
2126                 list_del(&packet->list);
2127                 htc_reclaim_rxbuf(target, packet,
2128                                   &target->endpoint[packet->endpoint]);
2129         }
2130
2131         list_for_each_entry_safe(packet, tmp_pkt, &tmp_rxq, list) {
2132                 list_del(&packet->list);
2133                 htc_reclaim_rxbuf(target, packet,
2134                                   &target->endpoint[packet->endpoint]);
2135         }
2136
2137         return status;
2138 }
2139
2140 int ath6kl_htc_rxmsg_pending_handler(struct htc_target *target,
2141                                      u32 msg_look_ahead, int *num_pkts)
2142 {
2143         struct htc_packet *packets, *tmp_pkt;
2144         struct htc_endpoint *endpoint;
2145         struct list_head rx_pktq, comp_pktq;
2146         int status = 0;
2147         u32 look_aheads[HTC_HOST_MAX_MSG_PER_BUNDLE];
2148         int num_look_ahead = 1;
2149         enum htc_endpoint_id id;
2150         int n_fetched = 0;
2151
2152         INIT_LIST_HEAD(&comp_pktq);
2153         *num_pkts = 0;
2154
2155         /*
2156          * On first entry copy the look_aheads into our temp array for
2157          * processing
2158          */
2159         look_aheads[0] = msg_look_ahead;
2160
2161         while (true) {
2162                 /*
2163                  * First lookahead sets the expected endpoint IDs for all
2164                  * packets in a bundle.
2165                  */
2166                 id = ((struct htc_frame_hdr *)&look_aheads[0])->eid;
2167                 endpoint = &target->endpoint[id];
2168
2169                 if (id >= ENDPOINT_MAX) {
2170                         ath6kl_err("MsgPend, invalid endpoint in look-ahead: %d\n",
2171                                    id);
2172                         status = -ENOMEM;
2173                         break;
2174                 }
2175
2176                 INIT_LIST_HEAD(&rx_pktq);
2177                 INIT_LIST_HEAD(&comp_pktq);
2178
2179                 /*
2180                  * Try to allocate as many HTC RX packets indicated by the
2181                  * look_aheads.
2182                  */
2183                 status = ath6kl_htc_rx_alloc(target, look_aheads,
2184                                              num_look_ahead, endpoint,
2185                                              &rx_pktq);
2186                 if (status)
2187                         break;
2188
2189                 if (get_queue_depth(&rx_pktq) >= 2)
2190                         /*
2191                          * A recv bundle was detected, force IRQ status
2192                          * re-check again
2193                          */
2194                         target->chk_irq_status_cnt = 1;
2195
2196                 n_fetched += get_queue_depth(&rx_pktq);
2197
2198                 num_look_ahead = 0;
2199
2200                 status = ath6kl_htc_rx_fetch(target, &rx_pktq, &comp_pktq);
2201
2202                 if (!status)
2203                         ath6kl_htc_rx_chk_water_mark(endpoint);
2204
2205                 /* Process fetched packets */
2206                 status = ath6kl_htc_rx_process_packets(target, &comp_pktq,
2207                                                        look_aheads,
2208                                                        &num_look_ahead);
2209
2210                 if (!num_look_ahead || status)
2211                         break;
2212
2213                 /*
2214                  * For SYNCH processing, if we get here, we are running
2215                  * through the loop again due to a detected lookahead. Set
2216                  * flag that we should re-check IRQ status registers again
2217                  * before leaving IRQ processing, this can net better
2218                  * performance in high throughput situations.
2219                  */
2220                 target->chk_irq_status_cnt = 1;
2221         }
2222
2223         if (status) {
2224                 if (status != -ECANCELED)
2225                         ath6kl_err("failed to get pending recv messages: %d\n",
2226                                    status);
2227
2228                 /* cleanup any packets in sync completion queue */
2229                 list_for_each_entry_safe(packets, tmp_pkt, &comp_pktq, list) {
2230                         list_del(&packets->list);
2231                         htc_reclaim_rxbuf(target, packets,
2232                                           &target->endpoint[packets->endpoint]);
2233                 }
2234
2235                 if (target->htc_flags & HTC_OP_STATE_STOPPING) {
2236                         ath6kl_warn("host is going to stop blocking receiver for htc_stop\n");
2237                         ath6kl_hif_rx_control(target->dev, false);
2238                 }
2239         }
2240
2241         /*
2242          * Before leaving, check to see if host ran out of buffers and
2243          * needs to stop the receiver.
2244          */
2245         if (target->rx_st_flags & HTC_RECV_WAIT_BUFFERS) {
2246                 ath6kl_warn("host has no rx buffers blocking receiver to prevent overrun\n");
2247                 ath6kl_hif_rx_control(target->dev, false);
2248         }
2249         *num_pkts = n_fetched;
2250
2251         return status;
2252 }
2253
2254 /*
2255  * Synchronously wait for a control message from the target,
2256  * This function is used at initialization time ONLY.  At init messages
2257  * on ENDPOINT 0 are expected.
2258  */
2259 static struct htc_packet *htc_wait_for_ctrl_msg(struct htc_target *target)
2260 {
2261         struct htc_packet *packet = NULL;
2262         struct htc_frame_look_ahead look_ahead;
2263
2264         if (ath6kl_hif_poll_mboxmsg_rx(target->dev, &look_ahead.word,
2265                                        HTC_TARGET_RESPONSE_TIMEOUT))
2266                 return NULL;
2267
2268         ath6kl_dbg(ATH6KL_DBG_HTC,
2269                    "htc rx wait ctrl look_ahead 0x%X\n", look_ahead.word);
2270
2271         if (look_ahead.eid != ENDPOINT_0)
2272                 return NULL;
2273
2274         packet = htc_get_control_buf(target, false);
2275
2276         if (!packet)
2277                 return NULL;
2278
2279         packet->info.rx.rx_flags = 0;
2280         packet->info.rx.exp_hdr = look_ahead.word;
2281         packet->act_len = le16_to_cpu(look_ahead.payld_len) + HTC_HDR_LENGTH;
2282
2283         if (packet->act_len > packet->buf_len)
2284                 goto fail_ctrl_rx;
2285
2286         /* we want synchronous operation */
2287         packet->completion = NULL;
2288
2289         /* get the message from the device, this will block */
2290         if (ath6kl_htc_rx_packet(target, packet, packet->act_len))
2291                 goto fail_ctrl_rx;
2292
2293         trace_ath6kl_htc_rx(packet->status, packet->endpoint,
2294                             packet->buf, packet->act_len);
2295
2296         /* process receive header */
2297         packet->status = ath6kl_htc_rx_process_hdr(target, packet, NULL, NULL);
2298
2299         if (packet->status) {
2300                 ath6kl_err("htc_wait_for_ctrl_msg, ath6kl_htc_rx_process_hdr failed (status = %d)\n",
2301                            packet->status);
2302                 goto fail_ctrl_rx;
2303         }
2304
2305         return packet;
2306
2307 fail_ctrl_rx:
2308         if (packet != NULL) {
2309                 htc_rxpkt_reset(packet);
2310                 reclaim_rx_ctrl_buf(target, packet);
2311         }
2312
2313         return NULL;
2314 }
2315
2316 static int ath6kl_htc_mbox_add_rxbuf_multiple(struct htc_target *target,
2317                                   struct list_head *pkt_queue)
2318 {
2319         struct htc_endpoint *endpoint;
2320         struct htc_packet *first_pkt;
2321         bool rx_unblock = false;
2322         int status = 0, depth;
2323
2324         if (list_empty(pkt_queue))
2325                 return -ENOMEM;
2326
2327         first_pkt = list_first_entry(pkt_queue, struct htc_packet, list);
2328
2329         if (first_pkt->endpoint >= ENDPOINT_MAX)
2330                 return status;
2331
2332         depth = get_queue_depth(pkt_queue);
2333
2334         ath6kl_dbg(ATH6KL_DBG_HTC,
2335                    "htc rx add multiple ep id %d cnt %d len %d\n",
2336                 first_pkt->endpoint, depth, first_pkt->buf_len);
2337
2338         endpoint = &target->endpoint[first_pkt->endpoint];
2339
2340         if (target->htc_flags & HTC_OP_STATE_STOPPING) {
2341                 struct htc_packet *packet, *tmp_pkt;
2342
2343                 /* walk through queue and mark each one canceled */
2344                 list_for_each_entry_safe(packet, tmp_pkt, pkt_queue, list) {
2345                         packet->status = -ECANCELED;
2346                         list_del(&packet->list);
2347                         ath6kl_htc_rx_complete(endpoint, packet);
2348                 }
2349
2350                 return status;
2351         }
2352
2353         spin_lock_bh(&target->rx_lock);
2354
2355         list_splice_tail_init(pkt_queue, &endpoint->rx_bufq);
2356
2357         /* check if we are blocked waiting for a new buffer */
2358         if (target->rx_st_flags & HTC_RECV_WAIT_BUFFERS) {
2359                 if (target->ep_waiting == first_pkt->endpoint) {
2360                         ath6kl_dbg(ATH6KL_DBG_HTC,
2361                                    "htc rx blocked on ep %d, unblocking\n",
2362                                    target->ep_waiting);
2363                         target->rx_st_flags &= ~HTC_RECV_WAIT_BUFFERS;
2364                         target->ep_waiting = ENDPOINT_MAX;
2365                         rx_unblock = true;
2366                 }
2367         }
2368
2369         spin_unlock_bh(&target->rx_lock);
2370
2371         if (rx_unblock && !(target->htc_flags & HTC_OP_STATE_STOPPING))
2372                 /* TODO : implement a buffer threshold count? */
2373                 ath6kl_hif_rx_control(target->dev, true);
2374
2375         return status;
2376 }
2377
2378 static void ath6kl_htc_mbox_flush_rx_buf(struct htc_target *target)
2379 {
2380         struct htc_endpoint *endpoint;
2381         struct htc_packet *packet, *tmp_pkt;
2382         int i;
2383
2384         for (i = ENDPOINT_0; i < ENDPOINT_MAX; i++) {
2385                 endpoint = &target->endpoint[i];
2386                 if (!endpoint->svc_id)
2387                         /* not in use.. */
2388                         continue;
2389
2390                 spin_lock_bh(&target->rx_lock);
2391                 list_for_each_entry_safe(packet, tmp_pkt,
2392                                          &endpoint->rx_bufq, list) {
2393                         list_del(&packet->list);
2394                         spin_unlock_bh(&target->rx_lock);
2395                         ath6kl_dbg(ATH6KL_DBG_HTC,
2396                                    "htc rx flush pkt 0x%p  len %d  ep %d\n",
2397                                    packet, packet->buf_len,
2398                                    packet->endpoint);
2399                         /*
2400                          * packets in rx_bufq of endpoint 0 have originally
2401                          * been queued from target->free_ctrl_rxbuf where
2402                          * packet and packet->buf_start are allocated
2403                          * separately using kmalloc(). For other endpoint
2404                          * rx_bufq, it is allocated as skb where packet is
2405                          * skb->head. Take care of this difference while freeing
2406                          * the memory.
2407                          */
2408                         if (packet->endpoint == ENDPOINT_0) {
2409                                 kfree(packet->buf_start);
2410                                 kfree(packet);
2411                         } else {
2412                                 dev_kfree_skb(packet->pkt_cntxt);
2413                         }
2414                         spin_lock_bh(&target->rx_lock);
2415                 }
2416                 spin_unlock_bh(&target->rx_lock);
2417         }
2418 }
2419
2420 static int ath6kl_htc_mbox_conn_service(struct htc_target *target,
2421                             struct htc_service_connect_req *conn_req,
2422                             struct htc_service_connect_resp *conn_resp)
2423 {
2424         struct htc_packet *rx_pkt = NULL;
2425         struct htc_packet *tx_pkt = NULL;
2426         struct htc_conn_service_resp *resp_msg;
2427         struct htc_conn_service_msg *conn_msg;
2428         struct htc_endpoint *endpoint;
2429         enum htc_endpoint_id assigned_ep = ENDPOINT_MAX;
2430         unsigned int max_msg_sz = 0;
2431         int status = 0;
2432         u16 msg_id;
2433
2434         ath6kl_dbg(ATH6KL_DBG_HTC,
2435                    "htc connect service target 0x%p service id 0x%x\n",
2436                    target, conn_req->svc_id);
2437
2438         if (conn_req->svc_id == HTC_CTRL_RSVD_SVC) {
2439                 /* special case for pseudo control service */
2440                 assigned_ep = ENDPOINT_0;
2441                 max_msg_sz = HTC_MAX_CTRL_MSG_LEN;
2442         } else {
2443                 /* allocate a packet to send to the target */
2444                 tx_pkt = htc_get_control_buf(target, true);
2445
2446                 if (!tx_pkt)
2447                         return -ENOMEM;
2448
2449                 conn_msg = (struct htc_conn_service_msg *)tx_pkt->buf;
2450                 memset(conn_msg, 0, sizeof(*conn_msg));
2451                 conn_msg->msg_id = cpu_to_le16(HTC_MSG_CONN_SVC_ID);
2452                 conn_msg->svc_id = cpu_to_le16(conn_req->svc_id);
2453                 conn_msg->conn_flags = cpu_to_le16(conn_req->conn_flags);
2454
2455                 set_htc_pkt_info(tx_pkt, NULL, (u8 *) conn_msg,
2456                                  sizeof(*conn_msg) + conn_msg->svc_meta_len,
2457                                  ENDPOINT_0, HTC_SERVICE_TX_PACKET_TAG);
2458
2459                 /* we want synchronous operation */
2460                 tx_pkt->completion = NULL;
2461                 ath6kl_htc_tx_prep_pkt(tx_pkt, 0, 0, 0);
2462                 status = ath6kl_htc_tx_issue(target, tx_pkt);
2463
2464                 if (status)
2465                         goto fail_tx;
2466
2467                 /* wait for response */
2468                 rx_pkt = htc_wait_for_ctrl_msg(target);
2469
2470                 if (!rx_pkt) {
2471                         status = -ENOMEM;
2472                         goto fail_tx;
2473                 }
2474
2475                 resp_msg = (struct htc_conn_service_resp *)rx_pkt->buf;
2476                 msg_id = le16_to_cpu(resp_msg->msg_id);
2477
2478                 if ((msg_id != HTC_MSG_CONN_SVC_RESP_ID) ||
2479                     (rx_pkt->act_len < sizeof(*resp_msg))) {
2480                         status = -ENOMEM;
2481                         goto fail_tx;
2482                 }
2483
2484                 conn_resp->resp_code = resp_msg->status;
2485                 /* check response status */
2486                 if (resp_msg->status != HTC_SERVICE_SUCCESS) {
2487                         ath6kl_err("target failed service 0x%X connect request (status:%d)\n",
2488                                    resp_msg->svc_id, resp_msg->status);
2489                         status = -ENOMEM;
2490                         goto fail_tx;
2491                 }
2492
2493                 assigned_ep = (enum htc_endpoint_id)resp_msg->eid;
2494                 max_msg_sz = le16_to_cpu(resp_msg->max_msg_sz);
2495         }
2496
2497         if (WARN_ON_ONCE(assigned_ep == ENDPOINT_UNUSED ||
2498                          assigned_ep >= ENDPOINT_MAX || !max_msg_sz)) {
2499                 status = -ENOMEM;
2500                 goto fail_tx;
2501         }
2502
2503         endpoint = &target->endpoint[assigned_ep];
2504         endpoint->eid = assigned_ep;
2505         if (endpoint->svc_id) {
2506                 status = -ENOMEM;
2507                 goto fail_tx;
2508         }
2509
2510         /* return assigned endpoint to caller */
2511         conn_resp->endpoint = assigned_ep;
2512         conn_resp->len_max = max_msg_sz;
2513
2514         /* setup the endpoint */
2515
2516         /* this marks the endpoint in use */
2517         endpoint->svc_id = conn_req->svc_id;
2518
2519         endpoint->max_txq_depth = conn_req->max_txq_depth;
2520         endpoint->len_max = max_msg_sz;
2521         endpoint->ep_cb = conn_req->ep_cb;
2522         endpoint->cred_dist.svc_id = conn_req->svc_id;
2523         endpoint->cred_dist.htc_ep = endpoint;
2524         endpoint->cred_dist.endpoint = assigned_ep;
2525         endpoint->cred_dist.cred_sz = target->tgt_cred_sz;
2526
2527         switch (endpoint->svc_id) {
2528         case WMI_DATA_BK_SVC:
2529                 endpoint->tx_drop_packet_threshold = MAX_DEF_COOKIE_NUM / 3;
2530                 break;
2531         default:
2532                 endpoint->tx_drop_packet_threshold = MAX_HI_COOKIE_NUM;
2533                 break;
2534         }
2535
2536         if (conn_req->max_rxmsg_sz) {
2537                 /*
2538                  * Override cred_per_msg calculation, this optimizes
2539                  * the credit-low indications since the host will actually
2540                  * issue smaller messages in the Send path.
2541                  */
2542                 if (conn_req->max_rxmsg_sz > max_msg_sz) {
2543                         status = -ENOMEM;
2544                         goto fail_tx;
2545                 }
2546                 endpoint->cred_dist.cred_per_msg =
2547                     conn_req->max_rxmsg_sz / target->tgt_cred_sz;
2548         } else
2549                 endpoint->cred_dist.cred_per_msg =
2550                     max_msg_sz / target->tgt_cred_sz;
2551
2552         if (!endpoint->cred_dist.cred_per_msg)
2553                 endpoint->cred_dist.cred_per_msg = 1;
2554
2555         /* save local connection flags */
2556         endpoint->conn_flags = conn_req->flags;
2557
2558 fail_tx:
2559         if (tx_pkt)
2560                 htc_reclaim_txctrl_buf(target, tx_pkt);
2561
2562         if (rx_pkt) {
2563                 htc_rxpkt_reset(rx_pkt);
2564                 reclaim_rx_ctrl_buf(target, rx_pkt);
2565         }
2566
2567         return status;
2568 }
2569
2570 static void reset_ep_state(struct htc_target *target)
2571 {
2572         struct htc_endpoint *endpoint;
2573         int i;
2574
2575         for (i = ENDPOINT_0; i < ENDPOINT_MAX; i++) {
2576                 endpoint = &target->endpoint[i];
2577                 memset(&endpoint->cred_dist, 0, sizeof(endpoint->cred_dist));
2578                 endpoint->svc_id = 0;
2579                 endpoint->len_max = 0;
2580                 endpoint->max_txq_depth = 0;
2581                 memset(&endpoint->ep_st, 0,
2582                        sizeof(endpoint->ep_st));
2583                 INIT_LIST_HEAD(&endpoint->rx_bufq);
2584                 INIT_LIST_HEAD(&endpoint->txq);
2585                 endpoint->target = target;
2586         }
2587
2588         /* reset distribution list */
2589         /* FIXME: free existing entries */
2590         INIT_LIST_HEAD(&target->cred_dist_list);
2591 }
2592
2593 static int ath6kl_htc_mbox_get_rxbuf_num(struct htc_target *target,
2594                              enum htc_endpoint_id endpoint)
2595 {
2596         int num;
2597
2598         spin_lock_bh(&target->rx_lock);
2599         num = get_queue_depth(&(target->endpoint[endpoint].rx_bufq));
2600         spin_unlock_bh(&target->rx_lock);
2601         return num;
2602 }
2603
2604 static void htc_setup_msg_bndl(struct htc_target *target)
2605 {
2606         /* limit what HTC can handle */
2607         target->msg_per_bndl_max = min(HTC_HOST_MAX_MSG_PER_BUNDLE,
2608                                        target->msg_per_bndl_max);
2609
2610         if (ath6kl_hif_enable_scatter(target->dev->ar)) {
2611                 target->msg_per_bndl_max = 0;
2612                 return;
2613         }
2614
2615         /* limit bundle what the device layer can handle */
2616         target->msg_per_bndl_max = min(target->max_scat_entries,
2617                                        target->msg_per_bndl_max);
2618
2619         ath6kl_dbg(ATH6KL_DBG_BOOT,
2620                    "htc bundling allowed msg_per_bndl_max %d\n",
2621                    target->msg_per_bndl_max);
2622
2623         /* Max rx bundle size is limited by the max tx bundle size */
2624         target->max_rx_bndl_sz = target->max_xfer_szper_scatreq;
2625         /* Max tx bundle size if limited by the extended mbox address range */
2626         target->max_tx_bndl_sz = min(HIF_MBOX0_EXT_WIDTH,
2627                                      target->max_xfer_szper_scatreq);
2628
2629         ath6kl_dbg(ATH6KL_DBG_BOOT, "htc max_rx_bndl_sz %d max_tx_bndl_sz %d\n",
2630                    target->max_rx_bndl_sz, target->max_tx_bndl_sz);
2631
2632         if (target->max_tx_bndl_sz)
2633                 /* tx_bndl_mask is enabled per AC, each has 1 bit */
2634                 target->tx_bndl_mask = (1 << WMM_NUM_AC) - 1;
2635
2636         if (target->max_rx_bndl_sz)
2637                 target->rx_bndl_enable = true;
2638
2639         if ((target->tgt_cred_sz % target->block_sz) != 0) {
2640                 ath6kl_warn("credit size: %d is not block aligned! Disabling send bundling\n",
2641                             target->tgt_cred_sz);
2642
2643                 /*
2644                  * Disallow send bundling since the credit size is
2645                  * not aligned to a block size the I/O block
2646                  * padding will spill into the next credit buffer
2647                  * which is fatal.
2648                  */
2649                 target->tx_bndl_mask = 0;
2650         }
2651 }
2652
2653 static int ath6kl_htc_mbox_wait_target(struct htc_target *target)
2654 {
2655         struct htc_packet *packet = NULL;
2656         struct htc_ready_ext_msg *rdy_msg;
2657         struct htc_service_connect_req connect;
2658         struct htc_service_connect_resp resp;
2659         int status;
2660
2661         /* we should be getting 1 control message that the target is ready */
2662         packet = htc_wait_for_ctrl_msg(target);
2663
2664         if (!packet)
2665                 return -ENOMEM;
2666
2667         /* we controlled the buffer creation so it's properly aligned */
2668         rdy_msg = (struct htc_ready_ext_msg *)packet->buf;
2669
2670         if ((le16_to_cpu(rdy_msg->ver2_0_info.msg_id) != HTC_MSG_READY_ID) ||
2671             (packet->act_len < sizeof(struct htc_ready_msg))) {
2672                 status = -ENOMEM;
2673                 goto fail_wait_target;
2674         }
2675
2676         if (!rdy_msg->ver2_0_info.cred_cnt || !rdy_msg->ver2_0_info.cred_sz) {
2677                 status = -ENOMEM;
2678                 goto fail_wait_target;
2679         }
2680
2681         target->tgt_creds = le16_to_cpu(rdy_msg->ver2_0_info.cred_cnt);
2682         target->tgt_cred_sz = le16_to_cpu(rdy_msg->ver2_0_info.cred_sz);
2683
2684         ath6kl_dbg(ATH6KL_DBG_BOOT,
2685                    "htc target ready credits %d size %d\n",
2686                    target->tgt_creds, target->tgt_cred_sz);
2687
2688         /* check if this is an extended ready message */
2689         if (packet->act_len >= sizeof(struct htc_ready_ext_msg)) {
2690                 /* this is an extended message */
2691                 target->htc_tgt_ver = rdy_msg->htc_ver;
2692                 target->msg_per_bndl_max = rdy_msg->msg_per_htc_bndl;
2693         } else {
2694                 /* legacy */
2695                 target->htc_tgt_ver = HTC_VERSION_2P0;
2696                 target->msg_per_bndl_max = 0;
2697         }
2698
2699         ath6kl_dbg(ATH6KL_DBG_BOOT, "htc using protocol %s (%d)\n",
2700                    (target->htc_tgt_ver == HTC_VERSION_2P0) ? "2.0" : ">= 2.1",
2701                    target->htc_tgt_ver);
2702
2703         if (target->msg_per_bndl_max > 0)
2704                 htc_setup_msg_bndl(target);
2705
2706         /* setup our pseudo HTC control endpoint connection */
2707         memset(&connect, 0, sizeof(connect));
2708         memset(&resp, 0, sizeof(resp));
2709         connect.ep_cb.rx = htc_ctrl_rx;
2710         connect.ep_cb.rx_refill = NULL;
2711         connect.ep_cb.tx_full = NULL;
2712         connect.max_txq_depth = NUM_CONTROL_BUFFERS;
2713         connect.svc_id = HTC_CTRL_RSVD_SVC;
2714
2715         /* connect fake service */
2716         status = ath6kl_htc_mbox_conn_service((void *)target, &connect, &resp);
2717
2718         if (status)
2719                 /*
2720                  * FIXME: this call doesn't make sense, the caller should
2721                  * call ath6kl_htc_mbox_cleanup() when it wants remove htc
2722                  */
2723                 ath6kl_hif_cleanup_scatter(target->dev->ar);
2724
2725 fail_wait_target:
2726         if (packet) {
2727                 htc_rxpkt_reset(packet);
2728                 reclaim_rx_ctrl_buf(target, packet);
2729         }
2730
2731         return status;
2732 }
2733
2734 /*
2735  * Start HTC, enable interrupts and let the target know
2736  * host has finished setup.
2737  */
2738 static int ath6kl_htc_mbox_start(struct htc_target *target)
2739 {
2740         struct htc_packet *packet;
2741         int status;
2742
2743         memset(&target->dev->irq_proc_reg, 0,
2744                sizeof(target->dev->irq_proc_reg));
2745
2746         /* Disable interrupts at the chip level */
2747         ath6kl_hif_disable_intrs(target->dev);
2748
2749         target->htc_flags = 0;
2750         target->rx_st_flags = 0;
2751
2752         /* Push control receive buffers into htc control endpoint */
2753         while ((packet = htc_get_control_buf(target, false)) != NULL) {
2754                 status = htc_add_rxbuf(target, packet);
2755                 if (status)
2756                         return status;
2757         }
2758
2759         /* NOTE: the first entry in the distribution list is ENDPOINT_0 */
2760         ath6kl_credit_init(target->credit_info, &target->cred_dist_list,
2761                            target->tgt_creds);
2762
2763         dump_cred_dist_stats(target);
2764
2765         /* Indicate to the target of the setup completion */
2766         status = htc_setup_tx_complete(target);
2767
2768         if (status)
2769                 return status;
2770
2771         /* unmask interrupts */
2772         status = ath6kl_hif_unmask_intrs(target->dev);
2773
2774         if (status)
2775                 ath6kl_htc_mbox_stop(target);
2776
2777         return status;
2778 }
2779
2780 static int ath6kl_htc_reset(struct htc_target *target)
2781 {
2782         u32 block_size, ctrl_bufsz;
2783         struct htc_packet *packet;
2784         int i;
2785
2786         reset_ep_state(target);
2787
2788         block_size = target->dev->ar->mbox_info.block_size;
2789
2790         ctrl_bufsz = (block_size > HTC_MAX_CTRL_MSG_LEN) ?
2791                       (block_size + HTC_HDR_LENGTH) :
2792                       (HTC_MAX_CTRL_MSG_LEN + HTC_HDR_LENGTH);
2793
2794         for (i = 0; i < NUM_CONTROL_BUFFERS; i++) {
2795                 packet = kzalloc(sizeof(*packet), GFP_KERNEL);
2796                 if (!packet)
2797                         return -ENOMEM;
2798
2799                 packet->buf_start = kzalloc(ctrl_bufsz, GFP_KERNEL);
2800                 if (!packet->buf_start) {
2801                         kfree(packet);
2802                         return -ENOMEM;
2803                 }
2804
2805                 packet->buf_len = ctrl_bufsz;
2806                 if (i < NUM_CONTROL_RX_BUFFERS) {
2807                         packet->act_len = 0;
2808                         packet->buf = packet->buf_start;
2809                         packet->endpoint = ENDPOINT_0;
2810                         list_add_tail(&packet->list, &target->free_ctrl_rxbuf);
2811                 } else {
2812                         list_add_tail(&packet->list, &target->free_ctrl_txbuf);
2813                 }
2814         }
2815
2816         return 0;
2817 }
2818
2819 /* htc_stop: stop interrupt reception, and flush all queued buffers */
2820 static void ath6kl_htc_mbox_stop(struct htc_target *target)
2821 {
2822         spin_lock_bh(&target->htc_lock);
2823         target->htc_flags |= HTC_OP_STATE_STOPPING;
2824         spin_unlock_bh(&target->htc_lock);
2825
2826         /*
2827          * Masking interrupts is a synchronous operation, when this
2828          * function returns all pending HIF I/O has completed, we can
2829          * safely flush the queues.
2830          */
2831         ath6kl_hif_mask_intrs(target->dev);
2832
2833         ath6kl_htc_flush_txep_all(target);
2834
2835         ath6kl_htc_mbox_flush_rx_buf(target);
2836
2837         ath6kl_htc_reset(target);
2838 }
2839
2840 static void *ath6kl_htc_mbox_create(struct ath6kl *ar)
2841 {
2842         struct htc_target *target = NULL;
2843         int status = 0;
2844
2845         target = kzalloc(sizeof(*target), GFP_KERNEL);
2846         if (!target) {
2847                 ath6kl_err("unable to allocate memory\n");
2848                 return NULL;
2849         }
2850
2851         target->dev = kzalloc(sizeof(*target->dev), GFP_KERNEL);
2852         if (!target->dev) {
2853                 ath6kl_err("unable to allocate memory\n");
2854                 kfree(target);
2855                 return NULL;
2856         }
2857
2858         spin_lock_init(&target->htc_lock);
2859         spin_lock_init(&target->rx_lock);
2860         spin_lock_init(&target->tx_lock);
2861
2862         INIT_LIST_HEAD(&target->free_ctrl_txbuf);
2863         INIT_LIST_HEAD(&target->free_ctrl_rxbuf);
2864         INIT_LIST_HEAD(&target->cred_dist_list);
2865
2866         target->dev->ar = ar;
2867         target->dev->htc_cnxt = target;
2868         target->ep_waiting = ENDPOINT_MAX;
2869
2870         status = ath6kl_hif_setup(target->dev);
2871         if (status)
2872                 goto err_htc_cleanup;
2873
2874         status = ath6kl_htc_reset(target);
2875         if (status)
2876                 goto err_htc_cleanup;
2877
2878         return target;
2879
2880 err_htc_cleanup:
2881         ath6kl_htc_mbox_cleanup(target);
2882
2883         return NULL;
2884 }
2885
2886 /* cleanup the HTC instance */
2887 static void ath6kl_htc_mbox_cleanup(struct htc_target *target)
2888 {
2889         struct htc_packet *packet, *tmp_packet;
2890
2891         ath6kl_hif_cleanup_scatter(target->dev->ar);
2892
2893         list_for_each_entry_safe(packet, tmp_packet,
2894                                  &target->free_ctrl_txbuf, list) {
2895                 list_del(&packet->list);
2896                 kfree(packet->buf_start);
2897                 kfree(packet);
2898         }
2899
2900         list_for_each_entry_safe(packet, tmp_packet,
2901                                  &target->free_ctrl_rxbuf, list) {
2902                 list_del(&packet->list);
2903                 kfree(packet->buf_start);
2904                 kfree(packet);
2905         }
2906
2907         kfree(target->dev);
2908         kfree(target);
2909 }
2910
2911 static const struct ath6kl_htc_ops ath6kl_htc_mbox_ops = {
2912         .create = ath6kl_htc_mbox_create,
2913         .wait_target = ath6kl_htc_mbox_wait_target,
2914         .start = ath6kl_htc_mbox_start,
2915         .conn_service = ath6kl_htc_mbox_conn_service,
2916         .tx = ath6kl_htc_mbox_tx,
2917         .stop = ath6kl_htc_mbox_stop,
2918         .cleanup = ath6kl_htc_mbox_cleanup,
2919         .flush_txep = ath6kl_htc_mbox_flush_txep,
2920         .flush_rx_buf = ath6kl_htc_mbox_flush_rx_buf,
2921         .activity_changed = ath6kl_htc_mbox_activity_changed,
2922         .get_rxbuf_num = ath6kl_htc_mbox_get_rxbuf_num,
2923         .add_rxbuf_multiple = ath6kl_htc_mbox_add_rxbuf_multiple,
2924         .credit_setup = ath6kl_htc_mbox_credit_setup,
2925 };
2926
2927 void ath6kl_htc_mbox_attach(struct ath6kl *ar)
2928 {
2929         ar->htc_ops = &ath6kl_htc_mbox_ops;
2930 }