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 <asm/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         /* Endianess? */
 368         put_unaligned((u16)packet->act_len, &hdr->payld_len);
 369         hdr->flags = flags;
 370         hdr->eid = packet->endpoint;
 371         hdr->ctrl[0] = ctrl0;
 372         hdr->ctrl[1] = ctrl1;
 373 }
 374
 375 static void htc_reclaim_txctrl_buf(struct htc_target *target,
 376                                    struct htc_packet *pkt)
 377 {
 378         spin_lock_bh(&target->htc_lock);
 379         list_add_tail(&pkt->list, &target->free_ctrl_txbuf);
 380         spin_unlock_bh(&target->htc_lock);
 381 }
 382
 383 static struct htc_packet *htc_get_control_buf(struct htc_target *target,
 384                                               bool tx)
 385 {
 386         struct htc_packet *packet = NULL;
 387         struct list_head *buf_list;
 388
 389         buf_list = tx ? &target->free_ctrl_txbuf : &target->free_ctrl_rxbuf;
 390
 391         spin_lock_bh(&target->htc_lock);
 392
 393         if (list_empty(buf_list)) {
 394                 spin_unlock_bh(&target->htc_lock);
 395                 return NULL;
 396         }
 397
 398         packet = list_first_entry(buf_list, struct htc_packet, list);
 399         list_del(&packet->list);
 400         spin_unlock_bh(&target->htc_lock);
 401
 402         if (tx)
 403                 packet->buf = packet->buf_start + HTC_HDR_LENGTH;
 404
 405         return packet;
 406 }
 407
 408 static void htc_tx_comp_update(struct htc_target *target,
 409                                struct htc_endpoint *endpoint,
 410                                struct htc_packet *packet)
 411 {
 412         packet->completion = NULL;
 413         packet->buf += HTC_HDR_LENGTH;
 414
 415         if (!packet->status)
 416                 return;
 417
 418         ath6kl_err("req failed (status:%d, ep:%d, len:%d creds:%d)\n",
 419                    packet->status, packet->endpoint, packet->act_len,
 420                    packet->info.tx.cred_used);
 421
 422         /* on failure to submit, reclaim credits for this packet */
 423         spin_lock_bh(&target->tx_lock);
 424         endpoint->cred_dist.cred_to_dist +=
 425                                 packet->info.tx.cred_used;
 426         endpoint->cred_dist.txq_depth = get_queue_depth(&endpoint->txq);
 427
 428         ath6kl_dbg(ATH6KL_DBG_HTC, "htc tx ctxt 0x%p dist 0x%p\n",
 429                    target->credit_info, &target->cred_dist_list);
 430
 431         ath6kl_credit_distribute(target->credit_info,
 432                                  &target->cred_dist_list,
 433                                  HTC_CREDIT_DIST_SEND_COMPLETE);
 434
 435         spin_unlock_bh(&target->tx_lock);
 436 }
 437
 438 static void htc_tx_complete(struct htc_endpoint *endpoint,
 439                             struct list_head *txq)
 440 {
 441         if (list_empty(txq))
 442                 return;
 443
 444         ath6kl_dbg(ATH6KL_DBG_HTC,
 445                    "htc tx complete ep %d pkts %d\n",
 446                    endpoint->eid, get_queue_depth(txq));
 447
 448         ath6kl_tx_complete(endpoint->target, txq);
 449 }
 450
 451 static void htc_tx_comp_handler(struct htc_target *target,
 452                                 struct htc_packet *packet)
 453 {
 454         struct htc_endpoint *endpoint = &target->endpoint[packet->endpoint];
 455         struct list_head container;
 456
 457         ath6kl_dbg(ATH6KL_DBG_HTC, "htc tx complete seqno %d\n",
 458                    packet->info.tx.seqno);
 459
 460         htc_tx_comp_update(target, endpoint, packet);
 461         INIT_LIST_HEAD(&container);
 462         list_add_tail(&packet->list, &container);
 463         /* do completion */
 464         htc_tx_complete(endpoint, &container);
 465 }
 466
 467 static void htc_async_tx_scat_complete(struct htc_target *target,
 468                                        struct hif_scatter_req *scat_req)
 469 {
 470         struct htc_endpoint *endpoint;
 471         struct htc_packet *packet;
 472         struct list_head tx_compq;
 473         int i;
 474
 475         INIT_LIST_HEAD(&tx_compq);
 476
 477         ath6kl_dbg(ATH6KL_DBG_HTC,
 478                    "htc tx scat complete len %d entries %d\n",
 479                    scat_req->len, scat_req->scat_entries);
 480
 481         if (scat_req->status)
 482                 ath6kl_err("send scatter req failed: %d\n", scat_req->status);
 483
 484         packet = scat_req->scat_list[0].packet;
 485         endpoint = &target->endpoint[packet->endpoint];
 486
 487         /* walk through the scatter list and process */
 488         for (i = 0; i < scat_req->scat_entries; i++) {
 489                 packet = scat_req->scat_list[i].packet;
 490                 if (!packet) {
 491                         WARN_ON(1);
 492                         return;
 493                 }
 494
 495                 packet->status = scat_req->status;
 496                 htc_tx_comp_update(target, endpoint, packet);
 497                 list_add_tail(&packet->list, &tx_compq);
 498         }
 499
 500         /* free scatter request */
 501         hif_scatter_req_add(target->dev->ar, scat_req);
 502
 503         /* complete all packets */
 504         htc_tx_complete(endpoint, &tx_compq);
 505 }
 506
 507 static int ath6kl_htc_tx_issue(struct htc_target *target,
 508                                struct htc_packet *packet)
 509 {
 510         int status;
 511         bool sync = false;
 512         u32 padded_len, send_len;
 513
 514         if (!packet->completion)
 515                 sync = true;
 516
 517         send_len = packet->act_len + HTC_HDR_LENGTH;
 518
 519         padded_len = CALC_TXRX_PADDED_LEN(target, send_len);
 520
 521         ath6kl_dbg(ATH6KL_DBG_HTC,
 522                    "htc tx issue len %d seqno %d padded_len %d mbox 0x%X %s\n",
 523                    send_len, packet->info.tx.seqno, padded_len,
 524                    target->dev->ar->mbox_info.htc_addr,
 525                    sync ? "sync" : "async");
 526
 527         if (sync) {
 528                 status = hif_read_write_sync(target->dev->ar,
 529                                 target->dev->ar->mbox_info.htc_addr,
 530                                  packet->buf, padded_len,
 531                                  HIF_WR_SYNC_BLOCK_INC);
 532
 533                 packet->status = status;
 534                 packet->buf += HTC_HDR_LENGTH;
 535         } else
 536                 status = hif_write_async(target->dev->ar,
 537                                 target->dev->ar->mbox_info.htc_addr,
 538                                 packet->buf, padded_len,
 539                                 HIF_WR_ASYNC_BLOCK_INC, packet);
 540
 541         trace_ath6kl_htc_tx(status, packet->endpoint, packet->buf, send_len);
 542
 543         return status;
 544 }
 545
 546 static int htc_check_credits(struct htc_target *target,
 547                              struct htc_endpoint *ep, u8 *flags,
 548                              enum htc_endpoint_id eid, unsigned int len,
 549                              int *req_cred)
 550 {
 551         *req_cred = (len > target->tgt_cred_sz) ?
 552                      DIV_ROUND_UP(len, target->tgt_cred_sz) : 1;
 553
 554         ath6kl_dbg(ATH6KL_DBG_CREDIT, "credit check need %d got %d\n",
 555                    *req_cred, ep->cred_dist.credits);
 556
 557         if (ep->cred_dist.credits < *req_cred) {
 558                 if (eid == ENDPOINT_0)
 559                         return -EINVAL;
 560
 561                 /* Seek more credits */
 562                 ep->cred_dist.seek_cred = *req_cred - ep->cred_dist.credits;
 563
 564                 ath6kl_credit_seek(target->credit_info, &ep->cred_dist);
 565
 566                 ep->cred_dist.seek_cred = 0;
 567
 568                 if (ep->cred_dist.credits < *req_cred) {
 569                         ath6kl_dbg(ATH6KL_DBG_CREDIT,
 570                                    "credit not found for ep %d\n",
 571                                    eid);
 572                         return -EINVAL;
 573                 }
 574         }
 575
 576         ep->cred_dist.credits -= *req_cred;
 577         ep->ep_st.cred_cosumd += *req_cred;
 578
 579          /* When we are getting low on credits, ask for more */
 580         if (ep->cred_dist.credits < ep->cred_dist.cred_per_msg) {
 581                 ep->cred_dist.seek_cred =
 582                 ep->cred_dist.cred_per_msg - ep->cred_dist.credits;
 583
 584                 ath6kl_credit_seek(target->credit_info, &ep->cred_dist);
 585
 586                 /* see if we were successful in getting more */
 587                 if (ep->cred_dist.credits < ep->cred_dist.cred_per_msg) {
 588                         /* tell the target we need credits ASAP! */
 589                         *flags |= HTC_FLAGS_NEED_CREDIT_UPDATE;
 590                         ep->ep_st.cred_low_indicate += 1;
 591                         ath6kl_dbg(ATH6KL_DBG_CREDIT,
 592                                    "credit we need credits asap\n");
 593                 }
 594         }
 595
 596         return 0;
 597 }
 598
 599 static void ath6kl_htc_tx_pkts_get(struct htc_target *target,
 600                                    struct htc_endpoint *endpoint,
 601                                    struct list_head *queue)
 602 {
 603         int req_cred;
 604         u8 flags;
 605         struct htc_packet *packet;
 606         unsigned int len;
 607
 608         while (true) {
 609                 flags = 0;
 610
 611                 if (list_empty(&endpoint->txq))
 612                         break;
 613                 packet = list_first_entry(&endpoint->txq, struct htc_packet,
 614                                           list);
 615
 616                 ath6kl_dbg(ATH6KL_DBG_HTC,
 617                            "htc tx got packet 0x%p queue depth %d\n",
 618                            packet, get_queue_depth(&endpoint->txq));
 619
 620                 len = CALC_TXRX_PADDED_LEN(target,
 621                                            packet->act_len + HTC_HDR_LENGTH);
 622
 623                 if (htc_check_credits(target, endpoint, &flags,
 624                                       packet->endpoint, len, &req_cred))
 625                         break;
 626
 627                 /* now we can fully move onto caller's queue */
 628                 packet = list_first_entry(&endpoint->txq, struct htc_packet,
 629                                           list);
 630                 list_move_tail(&packet->list, queue);
 631
 632                 /* save the number of credits this packet consumed */
 633                 packet->info.tx.cred_used = req_cred;
 634
 635                 /* all TX packets are handled asynchronously */
 636                 packet->completion = htc_tx_comp_handler;
 637                 packet->context = target;
 638                 endpoint->ep_st.tx_issued += 1;
 639
 640                 /* save send flags */
 641                 packet->info.tx.flags = flags;
 642                 packet->info.tx.seqno = endpoint->seqno;
 643                 endpoint->seqno++;
 644         }
 645 }
 646
 647 /* See if the padded tx length falls on a credit boundary */
 648 static int htc_get_credit_padding(unsigned int cred_sz, int *len,
 649                                   struct htc_endpoint *ep)
 650 {
 651         int rem_cred, cred_pad;
 652
 653         rem_cred = *len % cred_sz;
 654
 655         /* No padding needed */
 656         if  (!rem_cred)
 657                 return 0;
 658
 659         if (!(ep->conn_flags & HTC_FLGS_TX_BNDL_PAD_EN))
 660                 return -1;
 661
 662         /*
 663          * The transfer consumes a "partial" credit, this
 664          * packet cannot be bundled unless we add
 665          * additional "dummy" padding (max 255 bytes) to
 666          * consume the entire credit.
 667          */
 668         cred_pad = *len < cred_sz ? (cred_sz - *len) : rem_cred;
 669
 670         if ((cred_pad > 0) && (cred_pad <= 255))
 671                 *len += cred_pad;
 672         else
 673                 /* The amount of padding is too large, send as non-bundled */
 674                 return -1;
 675
 676         return cred_pad;
 677 }
 678
 679 static int ath6kl_htc_tx_setup_scat_list(struct htc_target *target,
 680                                          struct htc_endpoint *endpoint,
 681                                          struct hif_scatter_req *scat_req,
 682                                          int n_scat,
 683                                          struct list_head *queue)
 684 {
 685         struct htc_packet *packet;
 686         int i, len, rem_scat, cred_pad;
 687         int status = 0;
 688         u8 flags;
 689
 690         rem_scat = target->max_tx_bndl_sz;
 691
 692         for (i = 0; i < n_scat; i++) {
 693                 scat_req->scat_list[i].packet = NULL;
 694
 695                 if (list_empty(queue))
 696                         break;
 697
 698                 packet = list_first_entry(queue, struct htc_packet, list);
 699                 len = CALC_TXRX_PADDED_LEN(target,
 700                                            packet->act_len + HTC_HDR_LENGTH);
 701
 702                 cred_pad = htc_get_credit_padding(target->tgt_cred_sz,
 703                                                   &len, endpoint);
 704                 if (cred_pad < 0 || rem_scat < len) {
 705                         status = -ENOSPC;
 706                         break;
 707                 }
 708
 709                 rem_scat -= len;
 710                 /* now remove it from the queue */
 711                 list_del(&packet->list);
 712
 713                 scat_req->scat_list[i].packet = packet;
 714                 /* prepare packet and flag message as part of a send bundle */
 715                 flags = packet->info.tx.flags | HTC_FLAGS_SEND_BUNDLE;
 716                 ath6kl_htc_tx_prep_pkt(packet, flags,
 717                                        cred_pad, packet->info.tx.seqno);
 718                 /* Make sure the buffer is 4-byte aligned */
 719                 ath6kl_htc_tx_buf_align(&packet->buf,
 720                                         packet->act_len + HTC_HDR_LENGTH);
 721                 scat_req->scat_list[i].buf = packet->buf;
 722                 scat_req->scat_list[i].len = len;
 723
 724                 scat_req->len += len;
 725                 scat_req->scat_entries++;
 726                 ath6kl_dbg(ATH6KL_DBG_HTC,
 727                            "htc tx adding (%d) pkt 0x%p seqno %d len %d remaining %d\n",
 728                            i, packet, packet->info.tx.seqno, len, rem_scat);
 729         }
 730
 731         /* Roll back scatter setup in case of any failure */
 732         if (scat_req->scat_entries < HTC_MIN_HTC_MSGS_TO_BUNDLE) {
 733                 for (i = scat_req->scat_entries - 1; i >= 0; i--) {
 734                         packet = scat_req->scat_list[i].packet;
 735                         if (packet) {
 736                                 packet->buf += HTC_HDR_LENGTH;
 737                                 list_add(&packet->list, queue);
 738                         }
 739                 }
 740                 return -EAGAIN;
 741         }
 742
 743         return status;
 744 }
 745
 746 /*
 747  * Drain a queue and send as bundles this function may return without fully
 748  * draining the queue when
 749  *
 750  *    1. scatter resources are exhausted
 751  *    2. a message that will consume a partial credit will stop the
 752  *    bundling process early
 753  *    3. we drop below the minimum number of messages for a bundle
 754  */
 755 static void ath6kl_htc_tx_bundle(struct htc_endpoint *endpoint,
 756                                  struct list_head *queue,
 757                                  int *sent_bundle, int *n_bundle_pkts)
 758 {
 759         struct htc_target *target = endpoint->target;
 760         struct hif_scatter_req *scat_req = NULL;
 761         int n_scat, n_sent_bundle = 0, tot_pkts_bundle = 0, i;
 762         struct htc_packet *packet;
 763         int status;
 764         u32 txb_mask;
 765         u8 ac = WMM_NUM_AC;
 766
 767         if ((HTC_CTRL_RSVD_SVC != endpoint->svc_id) &&
 768             (WMI_CONTROL_SVC != endpoint->svc_id))
 769                 ac = target->dev->ar->ep2ac_map[endpoint->eid];
 770
 771         while (true) {
 772                 status = 0;
 773                 n_scat = get_queue_depth(queue);
 774                 n_scat = min(n_scat, target->msg_per_bndl_max);
 775
 776                 if (n_scat < HTC_MIN_HTC_MSGS_TO_BUNDLE)
 777                         /* not enough to bundle */
 778                         break;
 779
 780                 scat_req = hif_scatter_req_get(target->dev->ar);
 781
 782                 if (!scat_req) {
 783                         /* no scatter resources  */
 784                         ath6kl_dbg(ATH6KL_DBG_HTC,
 785                                    "htc tx no more scatter resources\n");
 786                         break;
 787                 }
 788
 789                 if ((ac < WMM_NUM_AC) && (ac != WMM_AC_BK)) {
 790                         if (WMM_AC_BE == ac)
 791                                 /*
 792                                  * BE, BK have priorities and bit
 793                                  * positions reversed
 794                                  */
 795                                 txb_mask = (1 << WMM_AC_BK);
 796                         else
 797                                 /*
 798                                  * any AC with priority lower than
 799                                  * itself
 800                                  */
 801                                 txb_mask = ((1 << ac) - 1);
 802
 803                         /*
 804                          * when the scatter request resources drop below a
 805                          * certain threshold, disable Tx bundling for all
 806                          * AC's with priority lower than the current requesting
 807                          * AC. Otherwise re-enable Tx bundling for them
 808                          */
 809                         if (scat_req->scat_q_depth < ATH6KL_SCATTER_REQS)
 810                                 target->tx_bndl_mask &= ~txb_mask;
 811                         else
 812                                 target->tx_bndl_mask |= txb_mask;
 813                 }
 814
 815                 ath6kl_dbg(ATH6KL_DBG_HTC, "htc tx pkts to scatter: %d\n",
 816                            n_scat);
 817
 818                 scat_req->len = 0;
 819                 scat_req->scat_entries = 0;
 820
 821                 status = ath6kl_htc_tx_setup_scat_list(target, endpoint,
 822                                                        scat_req, n_scat,
 823                                                        queue);
 824                 if (status == -EAGAIN) {
 825                         hif_scatter_req_add(target->dev->ar, scat_req);
 826                         break;
 827                 }
 828
 829                 /* send path is always asynchronous */
 830                 scat_req->complete = htc_async_tx_scat_complete;
 831                 n_sent_bundle++;
 832                 tot_pkts_bundle += scat_req->scat_entries;
 833
 834                 ath6kl_dbg(ATH6KL_DBG_HTC,
 835                            "htc tx scatter bytes %d entries %d\n",
 836                            scat_req->len, scat_req->scat_entries);
 837
 838                 for (i = 0; i < scat_req->scat_entries; i++) {
 839                         packet = scat_req->scat_list[i].packet;
 840                         trace_ath6kl_htc_tx(packet->status, packet->endpoint,
 841                                             packet->buf, packet->act_len);
 842                 }
 843
 844                 ath6kl_hif_submit_scat_req(target->dev, scat_req, false);
 845
 846                 if (status)
 847                         break;
 848         }
 849
 850         *sent_bundle = n_sent_bundle;
 851         *n_bundle_pkts = tot_pkts_bundle;
 852         ath6kl_dbg(ATH6KL_DBG_HTC, "htc tx bundle sent %d pkts\n",
 853                    n_sent_bundle);
 854
 855         return;
 856 }
 857
 858 static void ath6kl_htc_tx_from_queue(struct htc_target *target,
 859                                      struct htc_endpoint *endpoint)
 860 {
 861         struct list_head txq;
 862         struct htc_packet *packet;
 863         int bundle_sent;
 864         int n_pkts_bundle;
 865         u8 ac = WMM_NUM_AC;
 866         int status;
 867
 868         spin_lock_bh(&target->tx_lock);
 869
 870         endpoint->tx_proc_cnt++;
 871         if (endpoint->tx_proc_cnt > 1) {
 872                 endpoint->tx_proc_cnt--;
 873                 spin_unlock_bh(&target->tx_lock);
 874                 ath6kl_dbg(ATH6KL_DBG_HTC, "htc tx busy\n");
 875                 return;
 876         }
 877
 878         /*
 879          * drain the endpoint TX queue for transmission as long
 880          * as we have enough credits.
 881          */
 882         INIT_LIST_HEAD(&txq);
 883
 884         if ((HTC_CTRL_RSVD_SVC != endpoint->svc_id) &&
 885             (WMI_CONTROL_SVC != endpoint->svc_id))
 886                 ac = target->dev->ar->ep2ac_map[endpoint->eid];
 887
 888         while (true) {
 889                 if (list_empty(&endpoint->txq))
 890                         break;
 891
 892                 ath6kl_htc_tx_pkts_get(target, endpoint, &txq);
 893
 894                 if (list_empty(&txq))
 895                         break;
 896
 897                 spin_unlock_bh(&target->tx_lock);
 898
 899                 bundle_sent = 0;
 900                 n_pkts_bundle = 0;
 901
 902                 while (true) {
 903                         /* try to send a bundle on each pass */
 904                         if ((target->tx_bndl_mask) &&
 905                             (get_queue_depth(&txq) >=
 906                             HTC_MIN_HTC_MSGS_TO_BUNDLE)) {
 907                                 int temp1 = 0, temp2 = 0;
 908
 909                                 /* check if bundling is enabled for an AC */
 910                                 if (target->tx_bndl_mask & (1 << ac)) {
 911                                         ath6kl_htc_tx_bundle(endpoint, &txq,
 912                                                              &temp1, &temp2);
 913                                         bundle_sent += temp1;
 914                                         n_pkts_bundle += temp2;
 915                                 }
 916                         }
 917
 918                         if (list_empty(&txq))
 919                                 break;
 920
 921                         packet = list_first_entry(&txq, struct htc_packet,
 922                                                   list);
 923                         list_del(&packet->list);
 924
 925                         ath6kl_htc_tx_prep_pkt(packet, packet->info.tx.flags,
 926                                                0, packet->info.tx.seqno);
 927                         status = ath6kl_htc_tx_issue(target, packet);
 928
 929                         if (status) {
 930                                 packet->status = status;
 931                                 packet->completion(packet->context, packet);
 932                         }
 933                 }
 934
 935                 spin_lock_bh(&target->tx_lock);
 936
 937                 endpoint->ep_st.tx_bundles += bundle_sent;
 938                 endpoint->ep_st.tx_pkt_bundled += n_pkts_bundle;
 939
 940                 /*
 941                  * if an AC has bundling disabled and no tx bundling
 942                  * has occured continously for a certain number of TX,
 943                  * enable tx bundling for this AC
 944                  */
 945                 if (!bundle_sent) {
 946                         if (!(target->tx_bndl_mask & (1 << ac)) &&
 947                             (ac < WMM_NUM_AC)) {
 948                                 if (++target->ac_tx_count[ac] >=
 949                                         TX_RESUME_BUNDLE_THRESHOLD) {
 950                                         target->ac_tx_count[ac] = 0;
 951                                         target->tx_bndl_mask |= (1 << ac);
 952                                 }
 953                         }
 954                 } else {
 955                         /* tx bundling will reset the counter */
 956                         if (ac < WMM_NUM_AC)
 957                                 target->ac_tx_count[ac] = 0;
 958                 }
 959         }
 960
 961         endpoint->tx_proc_cnt = 0;
 962         spin_unlock_bh(&target->tx_lock);
 963 }
 964
 965 static bool ath6kl_htc_tx_try(struct htc_target *target,
 966                               struct htc_endpoint *endpoint,
 967                               struct htc_packet *tx_pkt)
 968 {
 969         struct htc_ep_callbacks ep_cb;
 970         int txq_depth;
 971         bool overflow = false;
 972
 973         ep_cb = endpoint->ep_cb;
 974
 975         spin_lock_bh(&target->tx_lock);
 976         txq_depth = get_queue_depth(&endpoint->txq);
 977         spin_unlock_bh(&target->tx_lock);
 978
 979         if (txq_depth >= endpoint->max_txq_depth)
 980                 overflow = true;
 981
 982         if (overflow)
 983                 ath6kl_dbg(ATH6KL_DBG_HTC,
 984                            "htc tx overflow ep %d depth %d max %d\n",
 985                            endpoint->eid, txq_depth,
 986                            endpoint->max_txq_depth);
 987
 988         if (overflow && ep_cb.tx_full) {
 989                 if (ep_cb.tx_full(endpoint->target, tx_pkt) ==
 990                     HTC_SEND_FULL_DROP) {
 991                         endpoint->ep_st.tx_dropped += 1;
 992                         return false;
 993                 }
 994         }
 995
 996         spin_lock_bh(&target->tx_lock);
 997         list_add_tail(&tx_pkt->list, &endpoint->txq);
 998         spin_unlock_bh(&target->tx_lock);
 999
1000         ath6kl_htc_tx_from_queue(target, endpoint);
1001
1002         return true;
1003 }
1004
1005 static void htc_chk_ep_txq(struct htc_target *target)
1006 {
1007         struct htc_endpoint *endpoint;
1008         struct htc_endpoint_credit_dist *cred_dist;
1009
1010         /*
1011          * Run through the credit distribution list to see if there are
1012          * packets queued. NOTE: no locks need to be taken since the
1013          * distribution list is not dynamic (cannot be re-ordered) and we
1014          * are not modifying any state.
1015          */
1016         list_for_each_entry(cred_dist, &target->cred_dist_list, list) {
1017                 endpoint = cred_dist->htc_ep;
1018
1019                 spin_lock_bh(&target->tx_lock);
1020                 if (!list_empty(&endpoint->txq)) {
1021                         ath6kl_dbg(ATH6KL_DBG_HTC,
1022                                    "htc creds ep %d credits %d pkts %d\n",
1023                                    cred_dist->endpoint,
1024                                    endpoint->cred_dist.credits,
1025                                    get_queue_depth(&endpoint->txq));
1026                         spin_unlock_bh(&target->tx_lock);
1027                         /*
1028                          * Try to start the stalled queue, this list is
1029                          * ordered by priority. If there are credits
1030                          * available the highest priority queue will get a
1031                          * chance to reclaim credits from lower priority
1032                          * ones.
1033                          */
1034                         ath6kl_htc_tx_from_queue(target, endpoint);
1035                         spin_lock_bh(&target->tx_lock);
1036                 }
1037                 spin_unlock_bh(&target->tx_lock);
1038         }
1039 }
1040
1041 static int htc_setup_tx_complete(struct htc_target *target)
1042 {
1043         struct htc_packet *send_pkt = NULL;
1044         int status;
1045
1046         send_pkt = htc_get_control_buf(target, true);
1047
1048         if (!send_pkt)
1049                 return -ENOMEM;
1050
1051         if (target->htc_tgt_ver >= HTC_VERSION_2P1) {
1052                 struct htc_setup_comp_ext_msg *setup_comp_ext;
1053                 u32 flags = 0;
1054
1055                 setup_comp_ext =
1056                     (struct htc_setup_comp_ext_msg *)send_pkt->buf;
1057                 memset(setup_comp_ext, 0, sizeof(*setup_comp_ext));
1058                 setup_comp_ext->msg_id =
1059                         cpu_to_le16(HTC_MSG_SETUP_COMPLETE_EX_ID);
1060
1061                 if (target->msg_per_bndl_max > 0) {
1062                         /* Indicate HTC bundling to the target */
1063                         flags |= HTC_SETUP_COMP_FLG_RX_BNDL_EN;
1064                         setup_comp_ext->msg_per_rxbndl =
1065                                                 target->msg_per_bndl_max;
1066                 }
1067
1068                 memcpy(&setup_comp_ext->flags, &flags,
1069                        sizeof(setup_comp_ext->flags));
1070                 set_htc_pkt_info(send_pkt, NULL, (u8 *) setup_comp_ext,
1071                                  sizeof(struct htc_setup_comp_ext_msg),
1072                                  ENDPOINT_0, HTC_SERVICE_TX_PACKET_TAG);
1073
1074         } else {
1075                 struct htc_setup_comp_msg *setup_comp;
1076                 setup_comp = (struct htc_setup_comp_msg *)send_pkt->buf;
1077                 memset(setup_comp, 0, sizeof(struct htc_setup_comp_msg));
1078                 setup_comp->msg_id = cpu_to_le16(HTC_MSG_SETUP_COMPLETE_ID);
1079                 set_htc_pkt_info(send_pkt, NULL, (u8 *) setup_comp,
1080                                  sizeof(struct htc_setup_comp_msg),
1081                                  ENDPOINT_0, HTC_SERVICE_TX_PACKET_TAG);
1082         }
1083
1084         /* we want synchronous operation */
1085         send_pkt->completion = NULL;
1086         ath6kl_htc_tx_prep_pkt(send_pkt, 0, 0, 0);
1087         status = ath6kl_htc_tx_issue(target, send_pkt);
1088
1089         if (send_pkt != NULL)
1090                 htc_reclaim_txctrl_buf(target, send_pkt);
1091
1092         return status;
1093 }
1094
1095 static void ath6kl_htc_set_credit_dist(struct htc_target *target,
1096                                 struct ath6kl_htc_credit_info *credit_info,
1097                                 u16 srvc_pri_order[], int list_len)
1098 {
1099         struct htc_endpoint *endpoint;
1100         int i, ep;
1101
1102         target->credit_info = credit_info;
1103
1104         list_add_tail(&target->endpoint[ENDPOINT_0].cred_dist.list,
1105                       &target->cred_dist_list);
1106
1107         for (i = 0; i < list_len; i++) {
1108                 for (ep = ENDPOINT_1; ep < ENDPOINT_MAX; ep++) {
1109                         endpoint = &target->endpoint[ep];
1110                         if (endpoint->svc_id == srvc_pri_order[i]) {
1111                                 list_add_tail(&endpoint->cred_dist.list,
1112                                               &target->cred_dist_list);
1113                                 break;
1114                         }
1115                 }
1116                 if (ep >= ENDPOINT_MAX) {
1117                         WARN_ON(1);
1118                         return;
1119                 }
1120         }
1121 }
1122
1123 static int ath6kl_htc_mbox_tx(struct htc_target *target,
1124                               struct htc_packet *packet)
1125 {
1126         struct htc_endpoint *endpoint;
1127         struct list_head queue;
1128
1129         ath6kl_dbg(ATH6KL_DBG_HTC,
1130                    "htc tx ep id %d buf 0x%p len %d\n",
1131                    packet->endpoint, packet->buf, packet->act_len);
1132
1133         if (packet->endpoint >= ENDPOINT_MAX) {
1134                 WARN_ON(1);
1135                 return -EINVAL;
1136         }
1137
1138         endpoint = &target->endpoint[packet->endpoint];
1139
1140         if (!ath6kl_htc_tx_try(target, endpoint, packet)) {
1141                 packet->status = (target->htc_flags & HTC_OP_STATE_STOPPING) ?
1142                                  -ECANCELED : -ENOSPC;
1143                 INIT_LIST_HEAD(&queue);
1144                 list_add(&packet->list, &queue);
1145                 htc_tx_complete(endpoint, &queue);
1146         }
1147
1148         return 0;
1149 }
1150
1151 /* flush endpoint TX queue */
1152 static void ath6kl_htc_mbox_flush_txep(struct htc_target *target,
1153                            enum htc_endpoint_id eid, u16 tag)
1154 {
1155         struct htc_packet *packet, *tmp_pkt;
1156         struct list_head discard_q, container;
1157         struct htc_endpoint *endpoint = &target->endpoint[eid];
1158
1159         if (!endpoint->svc_id) {
1160                 WARN_ON(1);
1161                 return;
1162         }
1163
1164         /* initialize the discard queue */
1165         INIT_LIST_HEAD(&discard_q);
1166
1167         spin_lock_bh(&target->tx_lock);
1168
1169         list_for_each_entry_safe(packet, tmp_pkt, &endpoint->txq, list) {
1170                 if ((tag == HTC_TX_PACKET_TAG_ALL) ||
1171                     (tag == packet->info.tx.tag))
1172                         list_move_tail(&packet->list, &discard_q);
1173         }
1174
1175         spin_unlock_bh(&target->tx_lock);
1176
1177         list_for_each_entry_safe(packet, tmp_pkt, &discard_q, list) {
1178                 packet->status = -ECANCELED;
1179                 list_del(&packet->list);
1180                 ath6kl_dbg(ATH6KL_DBG_HTC,
1181                            "htc tx flushing pkt 0x%p len %d  ep %d tag 0x%x\n",
1182                            packet, packet->act_len,
1183                            packet->endpoint, packet->info.tx.tag);
1184
1185                 INIT_LIST_HEAD(&container);
1186                 list_add_tail(&packet->list, &container);
1187                 htc_tx_complete(endpoint, &container);
1188         }
1189 }
1190
1191 static void ath6kl_htc_flush_txep_all(struct htc_target *target)
1192 {
1193         struct htc_endpoint *endpoint;
1194         int i;
1195
1196         dump_cred_dist_stats(target);
1197
1198         for (i = ENDPOINT_0; i < ENDPOINT_MAX; i++) {
1199                 endpoint = &target->endpoint[i];
1200                 if (endpoint->svc_id == 0)
1201                         /* not in use.. */
1202                         continue;
1203                 ath6kl_htc_mbox_flush_txep(target, i, HTC_TX_PACKET_TAG_ALL);
1204         }
1205 }
1206
1207 static void ath6kl_htc_mbox_activity_changed(struct htc_target *target,
1208                                              enum htc_endpoint_id eid,
1209                                              bool active)
1210 {
1211         struct htc_endpoint *endpoint = &target->endpoint[eid];
1212         bool dist = false;
1213
1214         if (endpoint->svc_id == 0) {
1215                 WARN_ON(1);
1216                 return;
1217         }
1218
1219         spin_lock_bh(&target->tx_lock);
1220
1221         if (active) {
1222                 if (!(endpoint->cred_dist.dist_flags & HTC_EP_ACTIVE)) {
1223                         endpoint->cred_dist.dist_flags |= HTC_EP_ACTIVE;
1224                         dist = true;
1225                 }
1226         } else {
1227                 if (endpoint->cred_dist.dist_flags & HTC_EP_ACTIVE) {
1228                         endpoint->cred_dist.dist_flags &= ~HTC_EP_ACTIVE;
1229                         dist = true;
1230                 }
1231         }
1232
1233         if (dist) {
1234                 endpoint->cred_dist.txq_depth =
1235                         get_queue_depth(&endpoint->txq);
1236
1237                 ath6kl_dbg(ATH6KL_DBG_HTC,
1238                            "htc tx activity ctxt 0x%p dist 0x%p\n",
1239                            target->credit_info, &target->cred_dist_list);
1240
1241                 ath6kl_credit_distribute(target->credit_info,
1242                                          &target->cred_dist_list,
1243                                          HTC_CREDIT_DIST_ACTIVITY_CHANGE);
1244         }
1245
1246         spin_unlock_bh(&target->tx_lock);
1247
1248         if (dist && !active)
1249                 htc_chk_ep_txq(target);
1250 }
1251
1252 /* HTC Rx */
1253
1254 static inline void ath6kl_htc_rx_update_stats(struct htc_endpoint *endpoint,
1255                                               int n_look_ahds)
1256 {
1257         endpoint->ep_st.rx_pkts++;
1258         if (n_look_ahds == 1)
1259                 endpoint->ep_st.rx_lkahds++;
1260         else if (n_look_ahds > 1)
1261                 endpoint->ep_st.rx_bundle_lkahd++;
1262 }
1263
1264 static inline bool htc_valid_rx_frame_len(struct htc_target *target,
1265                                           enum htc_endpoint_id eid, int len)
1266 {
1267         return (eid == target->dev->ar->ctrl_ep) ?
1268                 len <= ATH6KL_BUFFER_SIZE : len <= ATH6KL_AMSDU_BUFFER_SIZE;
1269 }
1270
1271 static int htc_add_rxbuf(struct htc_target *target, struct htc_packet *packet)
1272 {
1273         struct list_head queue;
1274
1275         INIT_LIST_HEAD(&queue);
1276         list_add_tail(&packet->list, &queue);
1277         return ath6kl_htc_mbox_add_rxbuf_multiple(target, &queue);
1278 }
1279
1280 static void htc_reclaim_rxbuf(struct htc_target *target,
1281                               struct htc_packet *packet,
1282                               struct htc_endpoint *ep)
1283 {
1284         if (packet->info.rx.rx_flags & HTC_RX_PKT_NO_RECYCLE) {
1285                 htc_rxpkt_reset(packet);
1286                 packet->status = -ECANCELED;
1287                 ep->ep_cb.rx(ep->target, packet);
1288         } else {
1289                 htc_rxpkt_reset(packet);
1290                 htc_add_rxbuf((void *)(target), packet);
1291         }
1292 }
1293
1294 static void reclaim_rx_ctrl_buf(struct htc_target *target,
1295                                 struct htc_packet *packet)
1296 {
1297         spin_lock_bh(&target->htc_lock);
1298         list_add_tail(&packet->list, &target->free_ctrl_rxbuf);
1299         spin_unlock_bh(&target->htc_lock);
1300 }
1301
1302 static int ath6kl_htc_rx_packet(struct htc_target *target,
1303                                 struct htc_packet *packet,
1304                                 u32 rx_len)
1305 {
1306         struct ath6kl_device *dev = target->dev;
1307         u32 padded_len;
1308         int status;
1309
1310         padded_len = CALC_TXRX_PADDED_LEN(target, rx_len);
1311
1312         if (padded_len > packet->buf_len) {
1313                 ath6kl_err("not enough receive space for packet - padlen %d recvlen %d bufferlen %d\n",
1314                            padded_len, rx_len, packet->buf_len);
1315                 return -ENOMEM;
1316         }
1317
1318         ath6kl_dbg(ATH6KL_DBG_HTC,
1319                    "htc rx 0x%p hdr 0x%x len %d mbox 0x%x\n",
1320                    packet, packet->info.rx.exp_hdr,
1321                    padded_len, dev->ar->mbox_info.htc_addr);
1322
1323         status = hif_read_write_sync(dev->ar,
1324                                      dev->ar->mbox_info.htc_addr,
1325                                      packet->buf, padded_len,
1326                                      HIF_RD_SYNC_BLOCK_FIX);
1327
1328         packet->status = status;
1329
1330         return status;
1331 }
1332
1333 /*
1334  * optimization for recv packets, we can indicate a
1335  * "hint" that there are more  single-packets to fetch
1336  * on this endpoint.
1337  */
1338 static void ath6kl_htc_rx_set_indicate(u32 lk_ahd,
1339                                        struct htc_endpoint *endpoint,
1340                                        struct htc_packet *packet)
1341 {
1342         struct htc_frame_hdr *htc_hdr = (struct htc_frame_hdr *)&lk_ahd;
1343
1344         if (htc_hdr->eid == packet->endpoint) {
1345                 if (!list_empty(&endpoint->rx_bufq))
1346                         packet->info.rx.indicat_flags |=
1347                                         HTC_RX_FLAGS_INDICATE_MORE_PKTS;
1348         }
1349 }
1350
1351 static void ath6kl_htc_rx_chk_water_mark(struct htc_endpoint *endpoint)
1352 {
1353         struct htc_ep_callbacks ep_cb = endpoint->ep_cb;
1354
1355         if (ep_cb.rx_refill_thresh > 0) {
1356                 spin_lock_bh(&endpoint->target->rx_lock);
1357                 if (get_queue_depth(&endpoint->rx_bufq)
1358                     < ep_cb.rx_refill_thresh) {
1359                         spin_unlock_bh(&endpoint->target->rx_lock);
1360                         ep_cb.rx_refill(endpoint->target, endpoint->eid);
1361                         return;
1362                 }
1363                 spin_unlock_bh(&endpoint->target->rx_lock);
1364         }
1365 }
1366
1367 /* This function is called with rx_lock held */
1368 static int ath6kl_htc_rx_setup(struct htc_target *target,
1369                                struct htc_endpoint *ep,
1370                                u32 *lk_ahds, struct list_head *queue, int n_msg)
1371 {
1372         struct htc_packet *packet;
1373         /* FIXME: type of lk_ahds can't be right */
1374         struct htc_frame_hdr *htc_hdr = (struct htc_frame_hdr *)lk_ahds;
1375         struct htc_ep_callbacks ep_cb;
1376         int status = 0, j, full_len;
1377         bool no_recycle;
1378
1379         full_len = CALC_TXRX_PADDED_LEN(target,
1380                                         le16_to_cpu(htc_hdr->payld_len) +
1381                                         sizeof(*htc_hdr));
1382
1383         if (!htc_valid_rx_frame_len(target, ep->eid, full_len)) {
1384                 ath6kl_warn("Rx buffer requested with invalid length htc_hdr:eid %d, flags 0x%x, len %d\n",
1385                             htc_hdr->eid, htc_hdr->flags,
1386                             le16_to_cpu(htc_hdr->payld_len));
1387                 return -EINVAL;
1388         }
1389
1390         ep_cb = ep->ep_cb;
1391         for (j = 0; j < n_msg; j++) {
1392                 /*
1393                  * Reset flag, any packets allocated using the
1394                  * rx_alloc() API cannot be recycled on
1395                  * cleanup,they must be explicitly returned.
1396                  */
1397                 no_recycle = false;
1398
1399                 if (ep_cb.rx_allocthresh &&
1400                     (full_len > ep_cb.rx_alloc_thresh)) {
1401                         ep->ep_st.rx_alloc_thresh_hit += 1;
1402                         ep->ep_st.rxalloc_thresh_byte +=
1403                                 le16_to_cpu(htc_hdr->payld_len);
1404
1405                         spin_unlock_bh(&target->rx_lock);
1406                         no_recycle = true;
1407
1408                         packet = ep_cb.rx_allocthresh(ep->target, ep->eid,
1409                                                       full_len);
1410                         spin_lock_bh(&target->rx_lock);
1411                 } else {
1412                         /* refill handler is being used */
1413                         if (list_empty(&ep->rx_bufq)) {
1414                                 if (ep_cb.rx_refill) {
1415                                         spin_unlock_bh(&target->rx_lock);
1416                                         ep_cb.rx_refill(ep->target, ep->eid);
1417                                         spin_lock_bh(&target->rx_lock);
1418                                 }
1419                         }
1420
1421                         if (list_empty(&ep->rx_bufq)) {
1422                                 packet = NULL;
1423                         } else {
1424                                 packet = list_first_entry(&ep->rx_bufq,
1425                                                 struct htc_packet, list);
1426                                 list_del(&packet->list);
1427                         }
1428                 }
1429
1430                 if (!packet) {
1431                         target->rx_st_flags |= HTC_RECV_WAIT_BUFFERS;
1432                         target->ep_waiting = ep->eid;
1433                         return -ENOSPC;
1434                 }
1435
1436                 /* clear flags */
1437                 packet->info.rx.rx_flags = 0;
1438                 packet->info.rx.indicat_flags = 0;
1439                 packet->status = 0;
1440
1441                 if (no_recycle)
1442                         /*
1443                          * flag that these packets cannot be
1444                          * recycled, they have to be returned to
1445                          * the user
1446                          */
1447                         packet->info.rx.rx_flags |= HTC_RX_PKT_NO_RECYCLE;
1448
1449                 /* Caller needs to free this upon any failure */
1450                 list_add_tail(&packet->list, queue);
1451
1452                 if (target->htc_flags & HTC_OP_STATE_STOPPING) {
1453                         status = -ECANCELED;
1454                         break;
1455                 }
1456
1457                 if (j) {
1458                         packet->info.rx.rx_flags |= HTC_RX_PKT_REFRESH_HDR;
1459                         packet->info.rx.exp_hdr = 0xFFFFFFFF;
1460                 } else
1461                         /* set expected look ahead */
1462                         packet->info.rx.exp_hdr = *lk_ahds;
1463
1464                 packet->act_len = le16_to_cpu(htc_hdr->payld_len) +
1465                         HTC_HDR_LENGTH;
1466         }
1467
1468         return status;
1469 }
1470
1471 static int ath6kl_htc_rx_alloc(struct htc_target *target,
1472                                u32 lk_ahds[], int msg,
1473                                struct htc_endpoint *endpoint,
1474                                struct list_head *queue)
1475 {
1476         int status = 0;
1477         struct htc_packet *packet, *tmp_pkt;
1478         struct htc_frame_hdr *htc_hdr;
1479         int i, n_msg;
1480
1481         spin_lock_bh(&target->rx_lock);
1482
1483         for (i = 0; i < msg; i++) {
1484                 htc_hdr = (struct htc_frame_hdr *)&lk_ahds[i];
1485
1486                 if (htc_hdr->eid >= ENDPOINT_MAX) {
1487                         ath6kl_err("invalid ep in look-ahead: %d\n",
1488                                    htc_hdr->eid);
1489                         status = -ENOMEM;
1490                         break;
1491                 }
1492
1493                 if (htc_hdr->eid != endpoint->eid) {
1494                         ath6kl_err("invalid ep in look-ahead: %d should be : %d (index:%d)\n",
1495                                    htc_hdr->eid, endpoint->eid, i);
1496                         status = -ENOMEM;
1497                         break;
1498                 }
1499
1500                 if (le16_to_cpu(htc_hdr->payld_len) > HTC_MAX_PAYLOAD_LENGTH) {
1501                         ath6kl_err("payload len %d exceeds max htc : %d !\n",
1502                                    htc_hdr->payld_len,
1503                                    (u32) HTC_MAX_PAYLOAD_LENGTH);
1504                         status = -ENOMEM;
1505                         break;
1506                 }
1507
1508                 if (endpoint->svc_id == 0) {
1509                         ath6kl_err("ep %d is not connected !\n", htc_hdr->eid);
1510                         status = -ENOMEM;
1511                         break;
1512                 }
1513
1514                 if (htc_hdr->flags & HTC_FLG_RX_BNDL_CNT) {
1515                         /*
1516                          * HTC header indicates that every packet to follow
1517                          * has the same padded length so that it can be
1518                          * optimally fetched as a full bundle.
1519                          */
1520                         n_msg = (htc_hdr->flags & HTC_FLG_RX_BNDL_CNT) >>
1521                                 HTC_FLG_RX_BNDL_CNT_S;
1522
1523                         /* the count doesn't include the starter frame */
1524                         n_msg++;
1525                         if (n_msg > target->msg_per_bndl_max) {
1526                                 status = -ENOMEM;
1527                                 break;
1528                         }
1529
1530                         endpoint->ep_st.rx_bundle_from_hdr += 1;
1531                         ath6kl_dbg(ATH6KL_DBG_HTC,
1532                                    "htc rx bundle pkts %d\n",
1533                                    n_msg);
1534                 } else
1535                         /* HTC header only indicates 1 message to fetch */
1536                         n_msg = 1;
1537
1538                 /* Setup packet buffers for each message */
1539                 status = ath6kl_htc_rx_setup(target, endpoint, &lk_ahds[i],
1540                                              queue, n_msg);
1541
1542                 /*
1543                  * This is due to unavailabilty of buffers to rx entire data.
1544                  * Return no error so that free buffers from queue can be used
1545                  * to receive partial data.
1546                  */
1547                 if (status == -ENOSPC) {
1548                         spin_unlock_bh(&target->rx_lock);
1549                         return 0;
1550                 }
1551
1552                 if (status)
1553                         break;
1554         }
1555
1556         spin_unlock_bh(&target->rx_lock);
1557
1558         if (status) {
1559                 list_for_each_entry_safe(packet, tmp_pkt, queue, list) {
1560                         list_del(&packet->list);
1561                         htc_reclaim_rxbuf(target, packet,
1562                                           &target->endpoint[packet->endpoint]);
1563                 }
1564         }
1565
1566         return status;
1567 }
1568
1569 static void htc_ctrl_rx(struct htc_target *context, struct htc_packet *packets)
1570 {
1571         if (packets->endpoint != ENDPOINT_0) {
1572                 WARN_ON(1);
1573                 return;
1574         }
1575
1576         if (packets->status == -ECANCELED) {
1577                 reclaim_rx_ctrl_buf(context, packets);
1578                 return;
1579         }
1580
1581         if (packets->act_len > 0) {
1582                 ath6kl_err("htc_ctrl_rx, got message with len:%zu\n",
1583                            packets->act_len + HTC_HDR_LENGTH);
1584
1585                 ath6kl_dbg_dump(ATH6KL_DBG_HTC,
1586                                 "htc rx unexpected endpoint 0 message", "",
1587                                 packets->buf - HTC_HDR_LENGTH,
1588                                 packets->act_len + HTC_HDR_LENGTH);
1589         }
1590
1591         htc_reclaim_rxbuf(context, packets, &context->endpoint[0]);
1592 }
1593
1594 static void htc_proc_cred_rpt(struct htc_target *target,
1595                               struct htc_credit_report *rpt,
1596                               int n_entries,
1597                               enum htc_endpoint_id from_ep)
1598 {
1599         struct htc_endpoint *endpoint;
1600         int tot_credits = 0, i;
1601         bool dist = false;
1602
1603         spin_lock_bh(&target->tx_lock);
1604
1605         for (i = 0; i < n_entries; i++, rpt++) {
1606                 if (rpt->eid >= ENDPOINT_MAX) {
1607                         WARN_ON(1);
1608                         spin_unlock_bh(&target->tx_lock);
1609                         return;
1610                 }
1611
1612                 endpoint = &target->endpoint[rpt->eid];
1613
1614                 ath6kl_dbg(ATH6KL_DBG_CREDIT,
1615                            "credit report ep %d credits %d\n",
1616                            rpt->eid, rpt->credits);
1617
1618                 endpoint->ep_st.tx_cred_rpt += 1;
1619                 endpoint->ep_st.cred_retnd += rpt->credits;
1620
1621                 if (from_ep == rpt->eid) {
1622                         /*
1623                          * This credit report arrived on the same endpoint
1624                          * indicating it arrived in an RX packet.
1625                          */
1626                         endpoint->ep_st.cred_from_rx += rpt->credits;
1627                         endpoint->ep_st.cred_rpt_from_rx += 1;
1628                 } else if (from_ep == ENDPOINT_0) {
1629                         /* credit arrived on endpoint 0 as a NULL message */
1630                         endpoint->ep_st.cred_from_ep0 += rpt->credits;
1631                         endpoint->ep_st.cred_rpt_ep0 += 1;
1632                 } else {
1633                         endpoint->ep_st.cred_from_other += rpt->credits;
1634                         endpoint->ep_st.cred_rpt_from_other += 1;
1635                 }
1636
1637                 if (rpt->eid == ENDPOINT_0)
1638                         /* always give endpoint 0 credits back */
1639                         endpoint->cred_dist.credits += rpt->credits;
1640                 else {
1641                         endpoint->cred_dist.cred_to_dist += rpt->credits;
1642                         dist = true;
1643                 }
1644
1645                 /*
1646                  * Refresh tx depth for distribution function that will
1647                  * recover these credits NOTE: this is only valid when
1648                  * there are credits to recover!
1649                  */
1650                 endpoint->cred_dist.txq_depth =
1651                         get_queue_depth(&endpoint->txq);
1652
1653                 tot_credits += rpt->credits;
1654         }
1655
1656         if (dist) {
1657                 /*
1658                  * This was a credit return based on a completed send
1659                  * operations note, this is done with the lock held
1660                  */
1661                 ath6kl_credit_distribute(target->credit_info,
1662                                          &target->cred_dist_list,
1663                                          HTC_CREDIT_DIST_SEND_COMPLETE);
1664         }
1665
1666         spin_unlock_bh(&target->tx_lock);
1667
1668         if (tot_credits)
1669                 htc_chk_ep_txq(target);
1670 }
1671
1672 static int htc_parse_trailer(struct htc_target *target,
1673                              struct htc_record_hdr *record,
1674                              u8 *record_buf, u32 *next_lk_ahds,
1675                              enum htc_endpoint_id endpoint,
1676                              int *n_lk_ahds)
1677 {
1678         struct htc_bundle_lkahd_rpt *bundle_lkahd_rpt;
1679         struct htc_lookahead_report *lk_ahd;
1680         int len;
1681
1682         switch (record->rec_id) {
1683         case HTC_RECORD_CREDITS:
1684                 len = record->len / sizeof(struct htc_credit_report);
1685                 if (!len) {
1686                         WARN_ON(1);
1687                         return -EINVAL;
1688                 }
1689
1690                 htc_proc_cred_rpt(target,
1691                                   (struct htc_credit_report *) record_buf,
1692                                   len, endpoint);
1693                 break;
1694         case HTC_RECORD_LOOKAHEAD:
1695                 len = record->len / sizeof(*lk_ahd);
1696                 if (!len) {
1697                         WARN_ON(1);
1698                         return -EINVAL;
1699                 }
1700
1701                 lk_ahd = (struct htc_lookahead_report *) record_buf;
1702                 if ((lk_ahd->pre_valid == ((~lk_ahd->post_valid) & 0xFF)) &&
1703                     next_lk_ahds) {
1704                         ath6kl_dbg(ATH6KL_DBG_HTC,
1705                                    "htc rx lk_ahd found pre_valid 0x%x post_valid 0x%x\n",
1706                                    lk_ahd->pre_valid, lk_ahd->post_valid);
1707
1708                         /* look ahead bytes are valid, copy them over */
1709                         memcpy((u8 *)&next_lk_ahds[0], lk_ahd->lk_ahd, 4);
1710
1711                         ath6kl_dbg_dump(ATH6KL_DBG_HTC,
1712                                         "htc rx next look ahead",
1713                                         "", next_lk_ahds, 4);
1714
1715                         *n_lk_ahds = 1;
1716                 }
1717                 break;
1718         case HTC_RECORD_LOOKAHEAD_BUNDLE:
1719                 len = record->len / sizeof(*bundle_lkahd_rpt);
1720                 if (!len || (len > HTC_HOST_MAX_MSG_PER_BUNDLE)) {
1721                         WARN_ON(1);
1722                         return -EINVAL;
1723                 }
1724
1725                 if (next_lk_ahds) {
1726                         int i;
1727
1728                         bundle_lkahd_rpt =
1729                                 (struct htc_bundle_lkahd_rpt *) record_buf;
1730
1731                         ath6kl_dbg_dump(ATH6KL_DBG_HTC, "htc rx bundle lk_ahd",
1732                                         "", record_buf, record->len);
1733
1734                         for (i = 0; i < len; i++) {
1735                                 memcpy((u8 *)&next_lk_ahds[i],
1736                                        bundle_lkahd_rpt->lk_ahd, 4);
1737                                 bundle_lkahd_rpt++;
1738                         }
1739
1740                         *n_lk_ahds = i;
1741                 }
1742                 break;
1743         default:
1744                 ath6kl_err("unhandled record: id:%d len:%d\n",
1745                            record->rec_id, record->len);
1746                 break;
1747         }
1748
1749         return 0;
1750 }
1751
1752 static int htc_proc_trailer(struct htc_target *target,
1753                             u8 *buf, int len, u32 *next_lk_ahds,
1754                             int *n_lk_ahds, enum htc_endpoint_id endpoint)
1755 {
1756         struct htc_record_hdr *record;
1757         int orig_len;
1758         int status;
1759         u8 *record_buf;
1760         u8 *orig_buf;
1761
1762         ath6kl_dbg(ATH6KL_DBG_HTC, "htc rx trailer len %d\n", len);
1763         ath6kl_dbg_dump(ATH6KL_DBG_HTC, NULL, "", buf, len);
1764
1765         orig_buf = buf;
1766         orig_len = len;
1767         status = 0;
1768
1769         while (len > 0) {
1770                 if (len < sizeof(struct htc_record_hdr)) {
1771                         status = -ENOMEM;
1772                         break;
1773                 }
1774                 /* these are byte aligned structs */
1775                 record = (struct htc_record_hdr *) buf;
1776                 len -= sizeof(struct htc_record_hdr);
1777                 buf += sizeof(struct htc_record_hdr);
1778
1779                 if (record->len > len) {
1780                         ath6kl_err("invalid record len: %d (id:%d) buf has: %d bytes left\n",
1781                                    record->len, record->rec_id, len);
1782                         status = -ENOMEM;
1783                         break;
1784                 }
1785                 record_buf = buf;
1786
1787                 status = htc_parse_trailer(target, record, record_buf,
1788                                            next_lk_ahds, endpoint, n_lk_ahds);
1789
1790                 if (status)
1791                         break;
1792
1793                 /* advance buffer past this record for next time around */
1794                 buf += record->len;
1795                 len -= record->len;
1796         }
1797
1798         if (status)
1799                 ath6kl_dbg_dump(ATH6KL_DBG_HTC, "htc rx bad trailer",
1800                                 "", orig_buf, orig_len);
1801
1802         return status;
1803 }
1804
1805 static int ath6kl_htc_rx_process_hdr(struct htc_target *target,
1806                                      struct htc_packet *packet,
1807                                      u32 *next_lkahds, int *n_lkahds)
1808 {
1809         int status = 0;
1810         u16 payload_len;
1811         u32 lk_ahd;
1812         struct htc_frame_hdr *htc_hdr = (struct htc_frame_hdr *)packet->buf;
1813
1814         if (n_lkahds != NULL)
1815                 *n_lkahds = 0;
1816
1817         /*
1818          * NOTE: we cannot assume the alignment of buf, so we use the safe
1819          * macros to retrieve 16 bit fields.
1820          */
1821         payload_len = le16_to_cpu(get_unaligned(&htc_hdr->payld_len));
1822
1823         memcpy((u8 *)&lk_ahd, packet->buf, sizeof(lk_ahd));
1824
1825         if (packet->info.rx.rx_flags & HTC_RX_PKT_REFRESH_HDR) {
1826                 /*
1827                  * Refresh the expected header and the actual length as it
1828                  * was unknown when this packet was grabbed as part of the
1829                  * bundle.
1830                  */
1831                 packet->info.rx.exp_hdr = lk_ahd;
1832                 packet->act_len = payload_len + HTC_HDR_LENGTH;
1833
1834                 /* validate the actual header that was refreshed  */
1835                 if (packet->act_len > packet->buf_len) {
1836                         ath6kl_err("refreshed hdr payload len (%d) in bundled recv is invalid (hdr: 0x%X)\n",
1837                                    payload_len, lk_ahd);
1838                         /*
1839                          * Limit this to max buffer just to print out some
1840                          * of the buffer.
1841                          */
1842                         packet->act_len = min(packet->act_len, packet->buf_len);
1843                         status = -ENOMEM;
1844                         goto fail_rx;
1845                 }
1846
1847                 if (packet->endpoint != htc_hdr->eid) {
1848                         ath6kl_err("refreshed hdr ep (%d) does not match expected ep (%d)\n",
1849                                    htc_hdr->eid, packet->endpoint);
1850                         status = -ENOMEM;
1851                         goto fail_rx;
1852                 }
1853         }
1854
1855         if (lk_ahd != packet->info.rx.exp_hdr) {
1856                 ath6kl_err("%s(): lk_ahd mismatch! (pPkt:0x%p flags:0x%X)\n",
1857                            __func__, packet, packet->info.rx.rx_flags);
1858                 ath6kl_dbg_dump(ATH6KL_DBG_HTC, "htc rx expected lk_ahd",
1859                                 "", &packet->info.rx.exp_hdr, 4);
1860                 ath6kl_dbg_dump(ATH6KL_DBG_HTC, "htc rx current header",
1861                                 "", (u8 *)&lk_ahd, sizeof(lk_ahd));
1862                 status = -ENOMEM;
1863                 goto fail_rx;
1864         }
1865
1866         if (htc_hdr->flags & HTC_FLG_RX_TRAILER) {
1867                 if (htc_hdr->ctrl[0] < sizeof(struct htc_record_hdr) ||
1868                     htc_hdr->ctrl[0] > payload_len) {
1869                         ath6kl_err("%s(): invalid hdr (payload len should be :%d, CB[0] is:%d)\n",
1870                                    __func__, payload_len, htc_hdr->ctrl[0]);
1871                         status = -ENOMEM;
1872                         goto fail_rx;
1873                 }
1874
1875                 if (packet->info.rx.rx_flags & HTC_RX_PKT_IGNORE_LOOKAHEAD) {
1876                         next_lkahds = NULL;
1877                         n_lkahds = NULL;
1878                 }
1879
1880                 status = htc_proc_trailer(target, packet->buf + HTC_HDR_LENGTH
1881                                           + payload_len - htc_hdr->ctrl[0],
1882                                           htc_hdr->ctrl[0], next_lkahds,
1883                                            n_lkahds, packet->endpoint);
1884
1885                 if (status)
1886                         goto fail_rx;
1887
1888                 packet->act_len -= htc_hdr->ctrl[0];
1889         }
1890
1891         packet->buf += HTC_HDR_LENGTH;
1892         packet->act_len -= HTC_HDR_LENGTH;
1893
1894 fail_rx:
1895         if (status)
1896                 ath6kl_dbg_dump(ATH6KL_DBG_HTC, "htc rx bad packet",
1897                                 "", packet->buf, packet->act_len);
1898
1899         return status;
1900 }
1901
1902 static void ath6kl_htc_rx_complete(struct htc_endpoint *endpoint,
1903                                    struct htc_packet *packet)
1904 {
1905                 ath6kl_dbg(ATH6KL_DBG_HTC,
1906                            "htc rx complete ep %d packet 0x%p\n",
1907                            endpoint->eid, packet);
1908
1909                 endpoint->ep_cb.rx(endpoint->target, packet);
1910 }
1911
1912 static int ath6kl_htc_rx_bundle(struct htc_target *target,
1913                                 struct list_head *rxq,
1914                                 struct list_head *sync_compq,
1915                                 int *n_pkt_fetched, bool part_bundle)
1916 {
1917         struct hif_scatter_req *scat_req;
1918         struct htc_packet *packet;
1919         int rem_space = target->max_rx_bndl_sz;
1920         int n_scat_pkt, status = 0, i, len;
1921
1922         n_scat_pkt = get_queue_depth(rxq);
1923         n_scat_pkt = min(n_scat_pkt, target->msg_per_bndl_max);
1924
1925         if ((get_queue_depth(rxq) - n_scat_pkt) > 0) {
1926                 /*
1927                  * We were forced to split this bundle receive operation
1928                  * all packets in this partial bundle must have their
1929                  * lookaheads ignored.
1930                  */
1931                 part_bundle = true;
1932
1933                 /*
1934                  * This would only happen if the target ignored our max
1935                  * bundle limit.
1936                  */
1937                 ath6kl_warn("%s(): partial bundle detected num:%d , %d\n",
1938                             __func__, get_queue_depth(rxq), n_scat_pkt);
1939         }
1940
1941         len = 0;
1942
1943         ath6kl_dbg(ATH6KL_DBG_HTC,
1944                    "htc rx bundle depth %d pkts %d\n",
1945                    get_queue_depth(rxq), n_scat_pkt);
1946
1947         scat_req = hif_scatter_req_get(target->dev->ar);
1948
1949         if (scat_req == NULL)
1950                 goto fail_rx_pkt;
1951
1952         for (i = 0; i < n_scat_pkt; i++) {
1953                 int pad_len;
1954
1955                 packet = list_first_entry(rxq, struct htc_packet, list);
1956                 list_del(&packet->list);
1957
1958                 pad_len = CALC_TXRX_PADDED_LEN(target,
1959                                                    packet->act_len);
1960
1961                 if ((rem_space - pad_len) < 0) {
1962                         list_add(&packet->list, rxq);
1963                         break;
1964                 }
1965
1966                 rem_space -= pad_len;
1967
1968                 if (part_bundle || (i < (n_scat_pkt - 1)))
1969                         /*
1970                          * Packet 0..n-1 cannot be checked for look-aheads
1971                          * since we are fetching a bundle the last packet
1972                          * however can have it's lookahead used
1973                          */
1974                         packet->info.rx.rx_flags |=
1975                             HTC_RX_PKT_IGNORE_LOOKAHEAD;
1976
1977                 /* NOTE: 1 HTC packet per scatter entry */
1978                 scat_req->scat_list[i].buf = packet->buf;
1979                 scat_req->scat_list[i].len = pad_len;
1980
1981                 packet->info.rx.rx_flags |= HTC_RX_PKT_PART_OF_BUNDLE;
1982
1983                 list_add_tail(&packet->list, sync_compq);
1984
1985                 WARN_ON(!scat_req->scat_list[i].len);
1986                 len += scat_req->scat_list[i].len;
1987         }
1988
1989         scat_req->len = len;
1990         scat_req->scat_entries = i;
1991
1992         status = ath6kl_hif_submit_scat_req(target->dev, scat_req, true);
1993
1994         if (!status)
1995                 *n_pkt_fetched = i;
1996
1997         /* free scatter request */
1998         hif_scatter_req_add(target->dev->ar, scat_req);
1999
2000 fail_rx_pkt:
2001
2002         return status;
2003 }
2004
2005 static int ath6kl_htc_rx_process_packets(struct htc_target *target,
2006                                          struct list_head *comp_pktq,
2007                                          u32 lk_ahds[],
2008                                          int *n_lk_ahd)
2009 {
2010         struct htc_packet *packet, *tmp_pkt;
2011         struct htc_endpoint *ep;
2012         int status = 0;
2013
2014         list_for_each_entry_safe(packet, tmp_pkt, comp_pktq, list) {
2015                 ep = &target->endpoint[packet->endpoint];
2016
2017                 trace_ath6kl_htc_rx(packet->status, packet->endpoint,
2018                                     packet->buf, packet->act_len);
2019
2020                 /* process header for each of the recv packet */
2021                 status = ath6kl_htc_rx_process_hdr(target, packet, lk_ahds,
2022                                                    n_lk_ahd);
2023                 if (status)
2024                         return status;
2025
2026                 list_del(&packet->list);
2027
2028                 if (list_empty(comp_pktq)) {
2029                         /*
2030                          * Last packet's more packet flag is set
2031                          * based on the lookahead.
2032                          */
2033                         if (*n_lk_ahd > 0)
2034                                 ath6kl_htc_rx_set_indicate(lk_ahds[0],
2035                                                            ep, packet);
2036                 } else
2037                         /*
2038                          * Packets in a bundle automatically have
2039                          * this flag set.
2040                          */
2041                         packet->info.rx.indicat_flags |=
2042                                 HTC_RX_FLAGS_INDICATE_MORE_PKTS;
2043
2044                 ath6kl_htc_rx_update_stats(ep, *n_lk_ahd);
2045
2046                 if (packet->info.rx.rx_flags & HTC_RX_PKT_PART_OF_BUNDLE)
2047                         ep->ep_st.rx_bundl += 1;
2048
2049                 ath6kl_htc_rx_complete(ep, packet);
2050         }
2051
2052         return status;
2053 }
2054
2055 static int ath6kl_htc_rx_fetch(struct htc_target *target,
2056                                struct list_head *rx_pktq,
2057                                struct list_head *comp_pktq)
2058 {
2059         int fetched_pkts;
2060         bool part_bundle = false;
2061         int status = 0;
2062         struct list_head tmp_rxq;
2063         struct htc_packet *packet, *tmp_pkt;
2064
2065         /* now go fetch the list of HTC packets */
2066         while (!list_empty(rx_pktq)) {
2067                 fetched_pkts = 0;
2068
2069                 INIT_LIST_HEAD(&tmp_rxq);
2070
2071                 if (target->rx_bndl_enable && (get_queue_depth(rx_pktq) > 1)) {
2072                         /*
2073                          * There are enough packets to attempt a
2074                          * bundle transfer and recv bundling is
2075                          * allowed.
2076                          */
2077                         status = ath6kl_htc_rx_bundle(target, rx_pktq,
2078                                                       &tmp_rxq,
2079                                                       &fetched_pkts,
2080                                                       part_bundle);
2081                         if (status)
2082                                 goto fail_rx;
2083
2084                         if (!list_empty(rx_pktq))
2085                                 part_bundle = true;
2086
2087                         list_splice_tail_init(&tmp_rxq, comp_pktq);
2088                 }
2089
2090                 if (!fetched_pkts) {
2091                         packet = list_first_entry(rx_pktq, struct htc_packet,
2092                                                    list);
2093
2094                         /* fully synchronous */
2095                         packet->completion = NULL;
2096
2097                         if (!list_is_singular(rx_pktq))
2098                                 /*
2099                                  * look_aheads in all packet
2100                                  * except the last one in the
2101                                  * bundle must be ignored
2102                                  */
2103                                 packet->info.rx.rx_flags |=
2104                                         HTC_RX_PKT_IGNORE_LOOKAHEAD;
2105
2106                         /* go fetch the packet */
2107                         status = ath6kl_htc_rx_packet(target, packet,
2108                                                       packet->act_len);
2109
2110                         list_move_tail(&packet->list, &tmp_rxq);
2111
2112                         if (status)
2113                                 goto fail_rx;
2114
2115                         list_splice_tail_init(&tmp_rxq, comp_pktq);
2116                 }
2117         }
2118
2119         return 0;
2120
2121 fail_rx:
2122
2123         /*
2124          * Cleanup any packets we allocated but didn't use to
2125          * actually fetch any packets.
2126          */
2127
2128         list_for_each_entry_safe(packet, tmp_pkt, rx_pktq, list) {
2129                 list_del(&packet->list);
2130                 htc_reclaim_rxbuf(target, packet,
2131                                   &target->endpoint[packet->endpoint]);
2132         }
2133
2134         list_for_each_entry_safe(packet, tmp_pkt, &tmp_rxq, list) {
2135                 list_del(&packet->list);
2136                 htc_reclaim_rxbuf(target, packet,
2137                                   &target->endpoint[packet->endpoint]);
2138         }
2139
2140         return status;
2141 }
2142
2143 int ath6kl_htc_rxmsg_pending_handler(struct htc_target *target,
2144                                      u32 msg_look_ahead, int *num_pkts)
2145 {
2146         struct htc_packet *packets, *tmp_pkt;
2147         struct htc_endpoint *endpoint;
2148         struct list_head rx_pktq, comp_pktq;
2149         int status = 0;
2150         u32 look_aheads[HTC_HOST_MAX_MSG_PER_BUNDLE];
2151         int num_look_ahead = 1;
2152         enum htc_endpoint_id id;
2153         int n_fetched = 0;
2154
2155         INIT_LIST_HEAD(&comp_pktq);
2156         *num_pkts = 0;
2157
2158         /*
2159          * On first entry copy the look_aheads into our temp array for
2160          * processing
2161          */
2162         look_aheads[0] = msg_look_ahead;
2163
2164         while (true) {
2165                 /*
2166                  * First lookahead sets the expected endpoint IDs for all
2167                  * packets in a bundle.
2168                  */
2169                 id = ((struct htc_frame_hdr *)&look_aheads[0])->eid;
2170                 endpoint = &target->endpoint[id];
2171
2172                 if (id >= ENDPOINT_MAX) {
2173                         ath6kl_err("MsgPend, invalid endpoint in look-ahead: %d\n",
2174                                    id);
2175                         status = -ENOMEM;
2176                         break;
2177                 }
2178
2179                 INIT_LIST_HEAD(&rx_pktq);
2180                 INIT_LIST_HEAD(&comp_pktq);
2181
2182                 /*
2183                  * Try to allocate as many HTC RX packets indicated by the
2184                  * look_aheads.
2185                  */
2186                 status = ath6kl_htc_rx_alloc(target, look_aheads,
2187                                              num_look_ahead, endpoint,
2188                                              &rx_pktq);
2189                 if (status)
2190                         break;
2191
2192                 if (get_queue_depth(&rx_pktq) >= 2)
2193                         /*
2194                          * A recv bundle was detected, force IRQ status
2195                          * re-check again
2196                          */
2197                         target->chk_irq_status_cnt = 1;
2198
2199                 n_fetched += get_queue_depth(&rx_pktq);
2200
2201                 num_look_ahead = 0;
2202
2203                 status = ath6kl_htc_rx_fetch(target, &rx_pktq, &comp_pktq);
2204
2205                 if (!status)
2206                         ath6kl_htc_rx_chk_water_mark(endpoint);
2207
2208                 /* Process fetched packets */
2209                 status = ath6kl_htc_rx_process_packets(target, &comp_pktq,
2210                                                        look_aheads,
2211                                                        &num_look_ahead);
2212
2213                 if (!num_look_ahead || status)
2214                         break;
2215
2216                 /*
2217                  * For SYNCH processing, if we get here, we are running
2218                  * through the loop again due to a detected lookahead. Set
2219                  * flag that we should re-check IRQ status registers again
2220                  * before leaving IRQ processing, this can net better
2221                  * performance in high throughput situations.
2222                  */
2223                 target->chk_irq_status_cnt = 1;
2224         }
2225
2226         if (status) {
2227                 ath6kl_err("failed to get pending recv messages: %d\n",
2228                            status);
2229
2230                 /* cleanup any packets in sync completion queue */
2231                 list_for_each_entry_safe(packets, tmp_pkt, &comp_pktq, list) {
2232                         list_del(&packets->list);
2233                         htc_reclaim_rxbuf(target, packets,
2234                                           &target->endpoint[packets->endpoint]);
2235                 }
2236
2237                 if (target->htc_flags & HTC_OP_STATE_STOPPING) {
2238                         ath6kl_warn("host is going to stop blocking receiver for htc_stop\n");
2239                         ath6kl_hif_rx_control(target->dev, false);
2240                 }
2241         }
2242
2243         /*
2244          * Before leaving, check to see if host ran out of buffers and
2245          * needs to stop the receiver.
2246          */
2247         if (target->rx_st_flags & HTC_RECV_WAIT_BUFFERS) {
2248                 ath6kl_warn("host has no rx buffers blocking receiver to prevent overrun\n");
2249                 ath6kl_hif_rx_control(target->dev, false);
2250         }
2251         *num_pkts = n_fetched;
2252
2253         return status;
2254 }
2255
2256 /*
2257  * Synchronously wait for a control message from the target,
2258  * This function is used at initialization time ONLY.  At init messages
2259  * on ENDPOINT 0 are expected.
2260  */
2261 static struct htc_packet *htc_wait_for_ctrl_msg(struct htc_target *target)
2262 {
2263         struct htc_packet *packet = NULL;
2264         struct htc_frame_hdr *htc_hdr;
2265         u32 look_ahead;
2266
2267         if (ath6kl_hif_poll_mboxmsg_rx(target->dev, &look_ahead,
2268                                        HTC_TARGET_RESPONSE_TIMEOUT))
2269                 return NULL;
2270
2271         ath6kl_dbg(ATH6KL_DBG_HTC,
2272                    "htc rx wait ctrl look_ahead 0x%X\n", look_ahead);
2273
2274         htc_hdr = (struct htc_frame_hdr *)&look_ahead;
2275
2276         if (htc_hdr->eid != ENDPOINT_0)
2277                 return NULL;
2278
2279         packet = htc_get_control_buf(target, false);
2280
2281         if (!packet)
2282                 return NULL;
2283
2284         packet->info.rx.rx_flags = 0;
2285         packet->info.rx.exp_hdr = look_ahead;
2286         packet->act_len = le16_to_cpu(htc_hdr->payld_len) + HTC_HDR_LENGTH;
2287
2288         if (packet->act_len > packet->buf_len)
2289                 goto fail_ctrl_rx;
2290
2291         /* we want synchronous operation */
2292         packet->completion = NULL;
2293
2294         /* get the message from the device, this will block */
2295         if (ath6kl_htc_rx_packet(target, packet, packet->act_len))
2296                 goto fail_ctrl_rx;
2297
2298         trace_ath6kl_htc_rx(packet->status, packet->endpoint,
2299                             packet->buf, packet->act_len);
2300
2301         /* process receive header */
2302         packet->status = ath6kl_htc_rx_process_hdr(target, packet, NULL, NULL);
2303
2304         if (packet->status) {
2305                 ath6kl_err("htc_wait_for_ctrl_msg, ath6kl_htc_rx_process_hdr failed (status = %d)\n",
2306                            packet->status);
2307                 goto fail_ctrl_rx;
2308         }
2309
2310         return packet;
2311
2312 fail_ctrl_rx:
2313         if (packet != NULL) {
2314                 htc_rxpkt_reset(packet);
2315                 reclaim_rx_ctrl_buf(target, packet);
2316         }
2317
2318         return NULL;
2319 }
2320
2321 static int ath6kl_htc_mbox_add_rxbuf_multiple(struct htc_target *target,
2322                                   struct list_head *pkt_queue)
2323 {
2324         struct htc_endpoint *endpoint;
2325         struct htc_packet *first_pkt;
2326         bool rx_unblock = false;
2327         int status = 0, depth;
2328
2329         if (list_empty(pkt_queue))
2330                 return -ENOMEM;
2331
2332         first_pkt = list_first_entry(pkt_queue, struct htc_packet, list);
2333
2334         if (first_pkt->endpoint >= ENDPOINT_MAX)
2335                 return status;
2336
2337         depth = get_queue_depth(pkt_queue);
2338
2339         ath6kl_dbg(ATH6KL_DBG_HTC,
2340                    "htc rx add multiple ep id %d cnt %d len %d\n",
2341                 first_pkt->endpoint, depth, first_pkt->buf_len);
2342
2343         endpoint = &target->endpoint[first_pkt->endpoint];
2344
2345         if (target->htc_flags & HTC_OP_STATE_STOPPING) {
2346                 struct htc_packet *packet, *tmp_pkt;
2347
2348                 /* walk through queue and mark each one canceled */
2349                 list_for_each_entry_safe(packet, tmp_pkt, pkt_queue, list) {
2350                         packet->status = -ECANCELED;
2351                         list_del(&packet->list);
2352                         ath6kl_htc_rx_complete(endpoint, packet);
2353                 }
2354
2355                 return status;
2356         }
2357
2358         spin_lock_bh(&target->rx_lock);
2359
2360         list_splice_tail_init(pkt_queue, &endpoint->rx_bufq);
2361
2362         /* check if we are blocked waiting for a new buffer */
2363         if (target->rx_st_flags & HTC_RECV_WAIT_BUFFERS) {
2364                 if (target->ep_waiting == first_pkt->endpoint) {
2365                         ath6kl_dbg(ATH6KL_DBG_HTC,
2366                                    "htc rx blocked on ep %d, unblocking\n",
2367                                    target->ep_waiting);
2368                         target->rx_st_flags &= ~HTC_RECV_WAIT_BUFFERS;
2369                         target->ep_waiting = ENDPOINT_MAX;
2370                         rx_unblock = true;
2371                 }
2372         }
2373
2374         spin_unlock_bh(&target->rx_lock);
2375
2376         if (rx_unblock && !(target->htc_flags & HTC_OP_STATE_STOPPING))
2377                 /* TODO : implement a buffer threshold count? */
2378                 ath6kl_hif_rx_control(target->dev, true);
2379
2380         return status;
2381 }
2382
2383 static void ath6kl_htc_mbox_flush_rx_buf(struct htc_target *target)
2384 {
2385         struct htc_endpoint *endpoint;
2386         struct htc_packet *packet, *tmp_pkt;
2387         int i;
2388
2389         for (i = ENDPOINT_0; i < ENDPOINT_MAX; i++) {
2390                 endpoint = &target->endpoint[i];
2391                 if (!endpoint->svc_id)
2392                         /* not in use.. */
2393                         continue;
2394
2395                 spin_lock_bh(&target->rx_lock);
2396                 list_for_each_entry_safe(packet, tmp_pkt,
2397                                          &endpoint->rx_bufq, list) {
2398                         list_del(&packet->list);
2399                         spin_unlock_bh(&target->rx_lock);
2400                         ath6kl_dbg(ATH6KL_DBG_HTC,
2401                                    "htc rx flush pkt 0x%p  len %d  ep %d\n",
2402                                    packet, packet->buf_len,
2403                                    packet->endpoint);
2404                         /*
2405                          * packets in rx_bufq of endpoint 0 have originally
2406                          * been queued from target->free_ctrl_rxbuf where
2407                          * packet and packet->buf_start are allocated
2408                          * separately using kmalloc(). For other endpoint
2409                          * rx_bufq, it is allocated as skb where packet is
2410                          * skb->head. Take care of this difference while freeing
2411                          * the memory.
2412                          */
2413                         if (packet->endpoint == ENDPOINT_0) {
2414                                 kfree(packet->buf_start);
2415                                 kfree(packet);
2416                         } else {
2417                                 dev_kfree_skb(packet->pkt_cntxt);
2418                         }
2419                         spin_lock_bh(&target->rx_lock);
2420                 }
2421                 spin_unlock_bh(&target->rx_lock);
2422         }
2423 }
2424
2425 static int ath6kl_htc_mbox_conn_service(struct htc_target *target,
2426                             struct htc_service_connect_req *conn_req,
2427                             struct htc_service_connect_resp *conn_resp)
2428 {
2429         struct htc_packet *rx_pkt = NULL;
2430         struct htc_packet *tx_pkt = NULL;
2431         struct htc_conn_service_resp *resp_msg;
2432         struct htc_conn_service_msg *conn_msg;
2433         struct htc_endpoint *endpoint;
2434         enum htc_endpoint_id assigned_ep = ENDPOINT_MAX;
2435         unsigned int max_msg_sz = 0;
2436         int status = 0;
2437         u16 msg_id;
2438
2439         ath6kl_dbg(ATH6KL_DBG_HTC,
2440                    "htc connect service target 0x%p service id 0x%x\n",
2441                    target, conn_req->svc_id);
2442
2443         if (conn_req->svc_id == HTC_CTRL_RSVD_SVC) {
2444                 /* special case for pseudo control service */
2445                 assigned_ep = ENDPOINT_0;
2446                 max_msg_sz = HTC_MAX_CTRL_MSG_LEN;
2447         } else {
2448                 /* allocate a packet to send to the target */
2449                 tx_pkt = htc_get_control_buf(target, true);
2450
2451                 if (!tx_pkt)
2452                         return -ENOMEM;
2453
2454                 conn_msg = (struct htc_conn_service_msg *)tx_pkt->buf;
2455                 memset(conn_msg, 0, sizeof(*conn_msg));
2456                 conn_msg->msg_id = cpu_to_le16(HTC_MSG_CONN_SVC_ID);
2457                 conn_msg->svc_id = cpu_to_le16(conn_req->svc_id);
2458                 conn_msg->conn_flags = cpu_to_le16(conn_req->conn_flags);
2459
2460                 set_htc_pkt_info(tx_pkt, NULL, (u8 *) conn_msg,
2461                                  sizeof(*conn_msg) + conn_msg->svc_meta_len,
2462                                  ENDPOINT_0, HTC_SERVICE_TX_PACKET_TAG);
2463
2464                 /* we want synchronous operation */
2465                 tx_pkt->completion = NULL;
2466                 ath6kl_htc_tx_prep_pkt(tx_pkt, 0, 0, 0);
2467                 status = ath6kl_htc_tx_issue(target, tx_pkt);
2468
2469                 if (status)
2470                         goto fail_tx;
2471
2472                 /* wait for response */
2473                 rx_pkt = htc_wait_for_ctrl_msg(target);
2474
2475                 if (!rx_pkt) {
2476                         status = -ENOMEM;
2477                         goto fail_tx;
2478                 }
2479
2480                 resp_msg = (struct htc_conn_service_resp *)rx_pkt->buf;
2481                 msg_id = le16_to_cpu(resp_msg->msg_id);
2482
2483                 if ((msg_id != HTC_MSG_CONN_SVC_RESP_ID) ||
2484                     (rx_pkt->act_len < sizeof(*resp_msg))) {
2485                         status = -ENOMEM;
2486                         goto fail_tx;
2487                 }
2488
2489                 conn_resp->resp_code = resp_msg->status;
2490                 /* check response status */
2491                 if (resp_msg->status != HTC_SERVICE_SUCCESS) {
2492                         ath6kl_err("target failed service 0x%X connect request (status:%d)\n",
2493                                    resp_msg->svc_id, resp_msg->status);
2494                         status = -ENOMEM;
2495                         goto fail_tx;
2496                 }
2497
2498                 assigned_ep = (enum htc_endpoint_id)resp_msg->eid;
2499                 max_msg_sz = le16_to_cpu(resp_msg->max_msg_sz);
2500         }
2501
2502         if (WARN_ON_ONCE(assigned_ep == ENDPOINT_UNUSED ||
2503                          assigned_ep >= ENDPOINT_MAX || !max_msg_sz)) {
2504                 status = -ENOMEM;
2505                 goto fail_tx;
2506         }
2507
2508         endpoint = &target->endpoint[assigned_ep];
2509         endpoint->eid = assigned_ep;
2510         if (endpoint->svc_id) {
2511                 status = -ENOMEM;
2512                 goto fail_tx;
2513         }
2514
2515         /* return assigned endpoint to caller */
2516         conn_resp->endpoint = assigned_ep;
2517         conn_resp->len_max = max_msg_sz;
2518
2519         /* setup the endpoint */
2520
2521         /* this marks the endpoint in use */
2522         endpoint->svc_id = conn_req->svc_id;
2523
2524         endpoint->max_txq_depth = conn_req->max_txq_depth;
2525         endpoint->len_max = max_msg_sz;
2526         endpoint->ep_cb = conn_req->ep_cb;
2527         endpoint->cred_dist.svc_id = conn_req->svc_id;
2528         endpoint->cred_dist.htc_ep = endpoint;
2529         endpoint->cred_dist.endpoint = assigned_ep;
2530         endpoint->cred_dist.cred_sz = target->tgt_cred_sz;
2531
2532         switch (endpoint->svc_id) {
2533         case WMI_DATA_BK_SVC:
2534                 endpoint->tx_drop_packet_threshold = MAX_DEF_COOKIE_NUM / 3;
2535                 break;
2536         default:
2537                 endpoint->tx_drop_packet_threshold = MAX_HI_COOKIE_NUM;
2538                 break;
2539         }
2540
2541         if (conn_req->max_rxmsg_sz) {
2542                 /*
2543                  * Override cred_per_msg calculation, this optimizes
2544                  * the credit-low indications since the host will actually
2545                  * issue smaller messages in the Send path.
2546                  */
2547                 if (conn_req->max_rxmsg_sz > max_msg_sz) {
2548                         status = -ENOMEM;
2549                         goto fail_tx;
2550                 }
2551                 endpoint->cred_dist.cred_per_msg =
2552                     conn_req->max_rxmsg_sz / target->tgt_cred_sz;
2553         } else
2554                 endpoint->cred_dist.cred_per_msg =
2555                     max_msg_sz / target->tgt_cred_sz;
2556
2557         if (!endpoint->cred_dist.cred_per_msg)
2558                 endpoint->cred_dist.cred_per_msg = 1;
2559
2560         /* save local connection flags */
2561         endpoint->conn_flags = conn_req->flags;
2562
2563 fail_tx:
2564         if (tx_pkt)
2565                 htc_reclaim_txctrl_buf(target, tx_pkt);
2566
2567         if (rx_pkt) {
2568                 htc_rxpkt_reset(rx_pkt);
2569                 reclaim_rx_ctrl_buf(target, rx_pkt);
2570         }
2571
2572         return status;
2573 }
2574
2575 static void reset_ep_state(struct htc_target *target)
2576 {
2577         struct htc_endpoint *endpoint;
2578         int i;
2579
2580         for (i = ENDPOINT_0; i < ENDPOINT_MAX; i++) {
2581                 endpoint = &target->endpoint[i];
2582                 memset(&endpoint->cred_dist, 0, sizeof(endpoint->cred_dist));
2583                 endpoint->svc_id = 0;
2584                 endpoint->len_max = 0;
2585                 endpoint->max_txq_depth = 0;
2586                 memset(&endpoint->ep_st, 0,
2587                        sizeof(endpoint->ep_st));
2588                 INIT_LIST_HEAD(&endpoint->rx_bufq);
2589                 INIT_LIST_HEAD(&endpoint->txq);
2590                 endpoint->target = target;
2591         }
2592
2593         /* reset distribution list */
2594         /* FIXME: free existing entries */
2595         INIT_LIST_HEAD(&target->cred_dist_list);
2596 }
2597
2598 static int ath6kl_htc_mbox_get_rxbuf_num(struct htc_target *target,
2599                              enum htc_endpoint_id endpoint)
2600 {
2601         int num;
2602
2603         spin_lock_bh(&target->rx_lock);
2604         num = get_queue_depth(&(target->endpoint[endpoint].rx_bufq));
2605         spin_unlock_bh(&target->rx_lock);
2606         return num;
2607 }
2608
2609 static void htc_setup_msg_bndl(struct htc_target *target)
2610 {
2611         /* limit what HTC can handle */
2612         target->msg_per_bndl_max = min(HTC_HOST_MAX_MSG_PER_BUNDLE,
2613                                        target->msg_per_bndl_max);
2614
2615         if (ath6kl_hif_enable_scatter(target->dev->ar)) {
2616                 target->msg_per_bndl_max = 0;
2617                 return;
2618         }
2619
2620         /* limit bundle what the device layer can handle */
2621         target->msg_per_bndl_max = min(target->max_scat_entries,
2622                                        target->msg_per_bndl_max);
2623
2624         ath6kl_dbg(ATH6KL_DBG_BOOT,
2625                    "htc bundling allowed msg_per_bndl_max %d\n",
2626                    target->msg_per_bndl_max);
2627
2628         /* Max rx bundle size is limited by the max tx bundle size */
2629         target->max_rx_bndl_sz = target->max_xfer_szper_scatreq;
2630         /* Max tx bundle size if limited by the extended mbox address range */
2631         target->max_tx_bndl_sz = min(HIF_MBOX0_EXT_WIDTH,
2632                                      target->max_xfer_szper_scatreq);
2633
2634         ath6kl_dbg(ATH6KL_DBG_BOOT, "htc max_rx_bndl_sz %d max_tx_bndl_sz %d\n",
2635                    target->max_rx_bndl_sz, target->max_tx_bndl_sz);
2636
2637         if (target->max_tx_bndl_sz)
2638                 /* tx_bndl_mask is enabled per AC, each has 1 bit */
2639                 target->tx_bndl_mask = (1 << WMM_NUM_AC) - 1;
2640
2641         if (target->max_rx_bndl_sz)
2642                 target->rx_bndl_enable = true;
2643
2644         if ((target->tgt_cred_sz % target->block_sz) != 0) {
2645                 ath6kl_warn("credit size: %d is not block aligned! Disabling send bundling\n",
2646                             target->tgt_cred_sz);
2647
2648                 /*
2649                  * Disallow send bundling since the credit size is
2650                  * not aligned to a block size the I/O block
2651                  * padding will spill into the next credit buffer
2652                  * which is fatal.
2653                  */
2654                 target->tx_bndl_mask = 0;
2655         }
2656 }
2657
2658 static int ath6kl_htc_mbox_wait_target(struct htc_target *target)
2659 {
2660         struct htc_packet *packet = NULL;
2661         struct htc_ready_ext_msg *rdy_msg;
2662         struct htc_service_connect_req connect;
2663         struct htc_service_connect_resp resp;
2664         int status;
2665
2666         /* we should be getting 1 control message that the target is ready */
2667         packet = htc_wait_for_ctrl_msg(target);
2668
2669         if (!packet)
2670                 return -ENOMEM;
2671
2672         /* we controlled the buffer creation so it's properly aligned */
2673         rdy_msg = (struct htc_ready_ext_msg *)packet->buf;
2674
2675         if ((le16_to_cpu(rdy_msg->ver2_0_info.msg_id) != HTC_MSG_READY_ID) ||
2676             (packet->act_len < sizeof(struct htc_ready_msg))) {
2677                 status = -ENOMEM;
2678                 goto fail_wait_target;
2679         }
2680
2681         if (!rdy_msg->ver2_0_info.cred_cnt || !rdy_msg->ver2_0_info.cred_sz) {
2682                 status = -ENOMEM;
2683                 goto fail_wait_target;
2684         }
2685
2686         target->tgt_creds = le16_to_cpu(rdy_msg->ver2_0_info.cred_cnt);
2687         target->tgt_cred_sz = le16_to_cpu(rdy_msg->ver2_0_info.cred_sz);
2688
2689         ath6kl_dbg(ATH6KL_DBG_BOOT,
2690                    "htc target ready credits %d size %d\n",
2691                    target->tgt_creds, target->tgt_cred_sz);
2692
2693         /* check if this is an extended ready message */
2694         if (packet->act_len >= sizeof(struct htc_ready_ext_msg)) {
2695                 /* this is an extended message */
2696                 target->htc_tgt_ver = rdy_msg->htc_ver;
2697                 target->msg_per_bndl_max = rdy_msg->msg_per_htc_bndl;
2698         } else {
2699                 /* legacy */
2700                 target->htc_tgt_ver = HTC_VERSION_2P0;
2701                 target->msg_per_bndl_max = 0;
2702         }
2703
2704         ath6kl_dbg(ATH6KL_DBG_BOOT, "htc using protocol %s (%d)\n",
2705                    (target->htc_tgt_ver == HTC_VERSION_2P0) ? "2.0" : ">= 2.1",
2706                    target->htc_tgt_ver);
2707
2708         if (target->msg_per_bndl_max > 0)
2709                 htc_setup_msg_bndl(target);
2710
2711         /* setup our pseudo HTC control endpoint connection */
2712         memset(&connect, 0, sizeof(connect));
2713         memset(&resp, 0, sizeof(resp));
2714         connect.ep_cb.rx = htc_ctrl_rx;
2715         connect.ep_cb.rx_refill = NULL;
2716         connect.ep_cb.tx_full = NULL;
2717         connect.max_txq_depth = NUM_CONTROL_BUFFERS;
2718         connect.svc_id = HTC_CTRL_RSVD_SVC;
2719
2720         /* connect fake service */
2721         status = ath6kl_htc_mbox_conn_service((void *)target, &connect, &resp);
2722
2723         if (status)
2724                 /*
2725                  * FIXME: this call doesn't make sense, the caller should
2726                  * call ath6kl_htc_mbox_cleanup() when it wants remove htc
2727                  */
2728                 ath6kl_hif_cleanup_scatter(target->dev->ar);
2729
2730 fail_wait_target:
2731         if (packet) {
2732                 htc_rxpkt_reset(packet);
2733                 reclaim_rx_ctrl_buf(target, packet);
2734         }
2735
2736         return status;
2737 }
2738
2739 /*
2740  * Start HTC, enable interrupts and let the target know
2741  * host has finished setup.
2742  */
2743 static int ath6kl_htc_mbox_start(struct htc_target *target)
2744 {
2745         struct htc_packet *packet;
2746         int status;
2747
2748         memset(&target->dev->irq_proc_reg, 0,
2749                sizeof(target->dev->irq_proc_reg));
2750
2751         /* Disable interrupts at the chip level */
2752         ath6kl_hif_disable_intrs(target->dev);
2753
2754         target->htc_flags = 0;
2755         target->rx_st_flags = 0;
2756
2757         /* Push control receive buffers into htc control endpoint */
2758         while ((packet = htc_get_control_buf(target, false)) != NULL) {
2759                 status = htc_add_rxbuf(target, packet);
2760                 if (status)
2761                         return status;
2762         }
2763
2764         /* NOTE: the first entry in the distribution list is ENDPOINT_0 */
2765         ath6kl_credit_init(target->credit_info, &target->cred_dist_list,
2766                            target->tgt_creds);
2767
2768         dump_cred_dist_stats(target);
2769
2770         /* Indicate to the target of the setup completion */
2771         status = htc_setup_tx_complete(target);
2772
2773         if (status)
2774                 return status;
2775
2776         /* unmask interrupts */
2777         status = ath6kl_hif_unmask_intrs(target->dev);
2778
2779         if (status)
2780                 ath6kl_htc_mbox_stop(target);
2781
2782         return status;
2783 }
2784
2785 static int ath6kl_htc_reset(struct htc_target *target)
2786 {
2787         u32 block_size, ctrl_bufsz;
2788         struct htc_packet *packet;
2789         int i;
2790
2791         reset_ep_state(target);
2792
2793         block_size = target->dev->ar->mbox_info.block_size;
2794
2795         ctrl_bufsz = (block_size > HTC_MAX_CTRL_MSG_LEN) ?
2796                       (block_size + HTC_HDR_LENGTH) :
2797                       (HTC_MAX_CTRL_MSG_LEN + HTC_HDR_LENGTH);
2798
2799         for (i = 0; i < NUM_CONTROL_BUFFERS; i++) {
2800                 packet = kzalloc(sizeof(*packet), GFP_KERNEL);
2801                 if (!packet)
2802                         return -ENOMEM;
2803
2804                 packet->buf_start = kzalloc(ctrl_bufsz, GFP_KERNEL);
2805                 if (!packet->buf_start) {
2806                         kfree(packet);
2807                         return -ENOMEM;
2808                 }
2809
2810                 packet->buf_len = ctrl_bufsz;
2811                 if (i < NUM_CONTROL_RX_BUFFERS) {
2812                         packet->act_len = 0;
2813                         packet->buf = packet->buf_start;
2814                         packet->endpoint = ENDPOINT_0;
2815                         list_add_tail(&packet->list, &target->free_ctrl_rxbuf);
2816                 } else {
2817                         list_add_tail(&packet->list, &target->free_ctrl_txbuf);
2818                 }
2819         }
2820
2821         return 0;
2822 }
2823
2824 /* htc_stop: stop interrupt reception, and flush all queued buffers */
2825 static void ath6kl_htc_mbox_stop(struct htc_target *target)
2826 {
2827         spin_lock_bh(&target->htc_lock);
2828         target->htc_flags |= HTC_OP_STATE_STOPPING;
2829         spin_unlock_bh(&target->htc_lock);
2830
2831         /*
2832          * Masking interrupts is a synchronous operation, when this
2833          * function returns all pending HIF I/O has completed, we can
2834          * safely flush the queues.
2835          */
2836         ath6kl_hif_mask_intrs(target->dev);
2837
2838         ath6kl_htc_flush_txep_all(target);
2839
2840         ath6kl_htc_mbox_flush_rx_buf(target);
2841
2842         ath6kl_htc_reset(target);
2843 }
2844
2845 static void *ath6kl_htc_mbox_create(struct ath6kl *ar)
2846 {
2847         struct htc_target *target = NULL;
2848         int status = 0;
2849
2850         target = kzalloc(sizeof(*target), GFP_KERNEL);
2851         if (!target) {
2852                 ath6kl_err("unable to allocate memory\n");
2853                 return NULL;
2854         }
2855
2856         target->dev = kzalloc(sizeof(*target->dev), GFP_KERNEL);
2857         if (!target->dev) {
2858                 ath6kl_err("unable to allocate memory\n");
2859                 status = -ENOMEM;
2860                 goto err_htc_cleanup;
2861         }
2862
2863         spin_lock_init(&target->htc_lock);
2864         spin_lock_init(&target->rx_lock);
2865         spin_lock_init(&target->tx_lock);
2866
2867         INIT_LIST_HEAD(&target->free_ctrl_txbuf);
2868         INIT_LIST_HEAD(&target->free_ctrl_rxbuf);
2869         INIT_LIST_HEAD(&target->cred_dist_list);
2870
2871         target->dev->ar = ar;
2872         target->dev->htc_cnxt = target;
2873         target->ep_waiting = ENDPOINT_MAX;
2874
2875         status = ath6kl_hif_setup(target->dev);
2876         if (status)
2877                 goto err_htc_cleanup;
2878
2879         status = ath6kl_htc_reset(target);
2880         if (status)
2881                 goto err_htc_cleanup;
2882
2883         return target;
2884
2885 err_htc_cleanup:
2886         ath6kl_htc_mbox_cleanup(target);
2887
2888         return NULL;
2889 }
2890
2891 /* cleanup the HTC instance */
2892 static void ath6kl_htc_mbox_cleanup(struct htc_target *target)
2893 {
2894         struct htc_packet *packet, *tmp_packet;
2895
2896         ath6kl_hif_cleanup_scatter(target->dev->ar);
2897
2898         list_for_each_entry_safe(packet, tmp_packet,
2899                                  &target->free_ctrl_txbuf, list) {
2900                 list_del(&packet->list);
2901                 kfree(packet->buf_start);
2902                 kfree(packet);
2903         }
2904
2905         list_for_each_entry_safe(packet, tmp_packet,
2906                                  &target->free_ctrl_rxbuf, list) {
2907                 list_del(&packet->list);
2908                 kfree(packet->buf_start);
2909                 kfree(packet);
2910         }
2911
2912         kfree(target->dev);
2913         kfree(target);
2914 }
2915
2916 static const struct ath6kl_htc_ops ath6kl_htc_mbox_ops = {
2917         .create = ath6kl_htc_mbox_create,
2918         .wait_target = ath6kl_htc_mbox_wait_target,
2919         .start = ath6kl_htc_mbox_start,
2920         .conn_service = ath6kl_htc_mbox_conn_service,
2921         .tx = ath6kl_htc_mbox_tx,
2922         .stop = ath6kl_htc_mbox_stop,
2923         .cleanup = ath6kl_htc_mbox_cleanup,
2924         .flush_txep = ath6kl_htc_mbox_flush_txep,
2925         .flush_rx_buf = ath6kl_htc_mbox_flush_rx_buf,
2926         .activity_changed = ath6kl_htc_mbox_activity_changed,
2927         .get_rxbuf_num = ath6kl_htc_mbox_get_rxbuf_num,
2928         .add_rxbuf_multiple = ath6kl_htc_mbox_add_rxbuf_multiple,
2929         .credit_setup = ath6kl_htc_mbox_credit_setup,
2930 };
2931
2932 void ath6kl_htc_mbox_attach(struct ath6kl *ar)
2933 {
2934         ar->htc_ops = &ath6kl_htc_mbox_ops;
2935 }