linux/drivers/net/wireless/ath/ath6kl/htc_mbox.c
<<
>>
Prefs
   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
  28static void ath6kl_htc_mbox_cleanup(struct htc_target *target);
  29static void ath6kl_htc_mbox_stop(struct htc_target *target);
  30static int ath6kl_htc_mbox_add_rxbuf_multiple(struct htc_target *target,
  31                                              struct list_head *pkt_queue);
  32static 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 */
  40static 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
  52static 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 */
 146static 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 */
 166static 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
 185static 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 */
 220static 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
 287out:
 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 */
 296static 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 */
 329static 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
 348static 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
 359static 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
 375static 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
 383static 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
 408static 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
 438static 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
 451static 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
 467static 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
 507static 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
 546static 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
 599static 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 */
 648static 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
 679static 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 */
 755static 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
 858static 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
 965static 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
1005static 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
1041static 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        htc_reclaim_txctrl_buf(target, send_pkt);
1089
1090        return status;
1091}
1092
1093static void ath6kl_htc_set_credit_dist(struct htc_target *target,
1094                                struct ath6kl_htc_credit_info *credit_info,
1095                                u16 srvc_pri_order[], int list_len)
1096{
1097        struct htc_endpoint *endpoint;
1098        int i, ep;
1099
1100        target->credit_info = credit_info;
1101
1102        list_add_tail(&target->endpoint[ENDPOINT_0].cred_dist.list,
1103                      &target->cred_dist_list);
1104
1105        for (i = 0; i < list_len; i++) {
1106                for (ep = ENDPOINT_1; ep < ENDPOINT_MAX; ep++) {
1107                        endpoint = &target->endpoint[ep];
1108                        if (endpoint->svc_id == srvc_pri_order[i]) {
1109                                list_add_tail(&endpoint->cred_dist.list,
1110                                              &target->cred_dist_list);
1111                                break;
1112                        }
1113                }
1114                if (ep >= ENDPOINT_MAX) {
1115                        WARN_ON(1);
1116                        return;
1117                }
1118        }
1119}
1120
1121static int ath6kl_htc_mbox_tx(struct htc_target *target,
1122                              struct htc_packet *packet)
1123{
1124        struct htc_endpoint *endpoint;
1125        struct list_head queue;
1126
1127        ath6kl_dbg(ATH6KL_DBG_HTC,
1128                   "htc tx ep id %d buf 0x%p len %d\n",
1129                   packet->endpoint, packet->buf, packet->act_len);
1130
1131        if (packet->endpoint >= ENDPOINT_MAX) {
1132                WARN_ON(1);
1133                return -EINVAL;
1134        }
1135
1136        endpoint = &target->endpoint[packet->endpoint];
1137
1138        if (!ath6kl_htc_tx_try(target, endpoint, packet)) {
1139                packet->status = (target->htc_flags & HTC_OP_STATE_STOPPING) ?
1140                                 -ECANCELED : -ENOSPC;
1141                INIT_LIST_HEAD(&queue);
1142                list_add(&packet->list, &queue);
1143                htc_tx_complete(endpoint, &queue);
1144        }
1145
1146        return 0;
1147}
1148
1149/* flush endpoint TX queue */
1150static void ath6kl_htc_mbox_flush_txep(struct htc_target *target,
1151                           enum htc_endpoint_id eid, u16 tag)
1152{
1153        struct htc_packet *packet, *tmp_pkt;
1154        struct list_head discard_q, container;
1155        struct htc_endpoint *endpoint = &target->endpoint[eid];
1156
1157        if (!endpoint->svc_id) {
1158                WARN_ON(1);
1159                return;
1160        }
1161
1162        /* initialize the discard queue */
1163        INIT_LIST_HEAD(&discard_q);
1164
1165        spin_lock_bh(&target->tx_lock);
1166
1167        list_for_each_entry_safe(packet, tmp_pkt, &endpoint->txq, list) {
1168                if ((tag == HTC_TX_PACKET_TAG_ALL) ||
1169                    (tag == packet->info.tx.tag))
1170                        list_move_tail(&packet->list, &discard_q);
1171        }
1172
1173        spin_unlock_bh(&target->tx_lock);
1174
1175        list_for_each_entry_safe(packet, tmp_pkt, &discard_q, list) {
1176                packet->status = -ECANCELED;
1177                list_del(&packet->list);
1178                ath6kl_dbg(ATH6KL_DBG_HTC,
1179                           "htc tx flushing pkt 0x%p len %d  ep %d tag 0x%x\n",
1180                           packet, packet->act_len,
1181                           packet->endpoint, packet->info.tx.tag);
1182
1183                INIT_LIST_HEAD(&container);
1184                list_add_tail(&packet->list, &container);
1185                htc_tx_complete(endpoint, &container);
1186        }
1187}
1188
1189static void ath6kl_htc_flush_txep_all(struct htc_target *target)
1190{
1191        struct htc_endpoint *endpoint;
1192        int i;
1193
1194        dump_cred_dist_stats(target);
1195
1196        for (i = ENDPOINT_0; i < ENDPOINT_MAX; i++) {
1197                endpoint = &target->endpoint[i];
1198                if (endpoint->svc_id == 0)
1199                        /* not in use.. */
1200                        continue;
1201                ath6kl_htc_mbox_flush_txep(target, i, HTC_TX_PACKET_TAG_ALL);
1202        }
1203}
1204
1205static void ath6kl_htc_mbox_activity_changed(struct htc_target *target,
1206                                             enum htc_endpoint_id eid,
1207                                             bool active)
1208{
1209        struct htc_endpoint *endpoint = &target->endpoint[eid];
1210        bool dist = false;
1211
1212        if (endpoint->svc_id == 0) {
1213                WARN_ON(1);
1214                return;
1215        }
1216
1217        spin_lock_bh(&target->tx_lock);
1218
1219        if (active) {
1220                if (!(endpoint->cred_dist.dist_flags & HTC_EP_ACTIVE)) {
1221                        endpoint->cred_dist.dist_flags |= HTC_EP_ACTIVE;
1222                        dist = true;
1223                }
1224        } else {
1225                if (endpoint->cred_dist.dist_flags & HTC_EP_ACTIVE) {
1226                        endpoint->cred_dist.dist_flags &= ~HTC_EP_ACTIVE;
1227                        dist = true;
1228                }
1229        }
1230
1231        if (dist) {
1232                endpoint->cred_dist.txq_depth =
1233                        get_queue_depth(&endpoint->txq);
1234
1235                ath6kl_dbg(ATH6KL_DBG_HTC,
1236                           "htc tx activity ctxt 0x%p dist 0x%p\n",
1237                           target->credit_info, &target->cred_dist_list);
1238
1239                ath6kl_credit_distribute(target->credit_info,
1240                                         &target->cred_dist_list,
1241                                         HTC_CREDIT_DIST_ACTIVITY_CHANGE);
1242        }
1243
1244        spin_unlock_bh(&target->tx_lock);
1245
1246        if (dist && !active)
1247                htc_chk_ep_txq(target);
1248}
1249
1250/* HTC Rx */
1251
1252static inline void ath6kl_htc_rx_update_stats(struct htc_endpoint *endpoint,
1253                                              int n_look_ahds)
1254{
1255        endpoint->ep_st.rx_pkts++;
1256        if (n_look_ahds == 1)
1257                endpoint->ep_st.rx_lkahds++;
1258        else if (n_look_ahds > 1)
1259                endpoint->ep_st.rx_bundle_lkahd++;
1260}
1261
1262static inline bool htc_valid_rx_frame_len(struct htc_target *target,
1263                                          enum htc_endpoint_id eid, int len)
1264{
1265        return (eid == target->dev->ar->ctrl_ep) ?
1266                len <= ATH6KL_BUFFER_SIZE : len <= ATH6KL_AMSDU_BUFFER_SIZE;
1267}
1268
1269static int htc_add_rxbuf(struct htc_target *target, struct htc_packet *packet)
1270{
1271        struct list_head queue;
1272
1273        INIT_LIST_HEAD(&queue);
1274        list_add_tail(&packet->list, &queue);
1275        return ath6kl_htc_mbox_add_rxbuf_multiple(target, &queue);
1276}
1277
1278static void htc_reclaim_rxbuf(struct htc_target *target,
1279                              struct htc_packet *packet,
1280                              struct htc_endpoint *ep)
1281{
1282        if (packet->info.rx.rx_flags & HTC_RX_PKT_NO_RECYCLE) {
1283                htc_rxpkt_reset(packet);
1284                packet->status = -ECANCELED;
1285                ep->ep_cb.rx(ep->target, packet);
1286        } else {
1287                htc_rxpkt_reset(packet);
1288                htc_add_rxbuf((void *)(target), packet);
1289        }
1290}
1291
1292static void reclaim_rx_ctrl_buf(struct htc_target *target,
1293                                struct htc_packet *packet)
1294{
1295        spin_lock_bh(&target->htc_lock);
1296        list_add_tail(&packet->list, &target->free_ctrl_rxbuf);
1297        spin_unlock_bh(&target->htc_lock);
1298}
1299
1300static int ath6kl_htc_rx_packet(struct htc_target *target,
1301                                struct htc_packet *packet,
1302                                u32 rx_len)
1303{
1304        struct ath6kl_device *dev = target->dev;
1305        u32 padded_len;
1306        int status;
1307
1308        padded_len = CALC_TXRX_PADDED_LEN(target, rx_len);
1309
1310        if (padded_len > packet->buf_len) {
1311                ath6kl_err("not enough receive space for packet - padlen %d recvlen %d bufferlen %d\n",
1312                           padded_len, rx_len, packet->buf_len);
1313                return -ENOMEM;
1314        }
1315
1316        ath6kl_dbg(ATH6KL_DBG_HTC,
1317                   "htc rx 0x%p hdr 0x%x len %d mbox 0x%x\n",
1318                   packet, packet->info.rx.exp_hdr,
1319                   padded_len, dev->ar->mbox_info.htc_addr);
1320
1321        status = hif_read_write_sync(dev->ar,
1322                                     dev->ar->mbox_info.htc_addr,
1323                                     packet->buf, padded_len,
1324                                     HIF_RD_SYNC_BLOCK_FIX);
1325
1326        packet->status = status;
1327
1328        return status;
1329}
1330
1331/*
1332 * optimization for recv packets, we can indicate a
1333 * "hint" that there are more  single-packets to fetch
1334 * on this endpoint.
1335 */
1336static void ath6kl_htc_rx_set_indicate(u32 lk_ahd,
1337                                       struct htc_endpoint *endpoint,
1338                                       struct htc_packet *packet)
1339{
1340        struct htc_frame_hdr *htc_hdr = (struct htc_frame_hdr *)&lk_ahd;
1341
1342        if (htc_hdr->eid == packet->endpoint) {
1343                if (!list_empty(&endpoint->rx_bufq))
1344                        packet->info.rx.indicat_flags |=
1345                                        HTC_RX_FLAGS_INDICATE_MORE_PKTS;
1346        }
1347}
1348
1349static void ath6kl_htc_rx_chk_water_mark(struct htc_endpoint *endpoint)
1350{
1351        struct htc_ep_callbacks ep_cb = endpoint->ep_cb;
1352
1353        if (ep_cb.rx_refill_thresh > 0) {
1354                spin_lock_bh(&endpoint->target->rx_lock);
1355                if (get_queue_depth(&endpoint->rx_bufq)
1356                    < ep_cb.rx_refill_thresh) {
1357                        spin_unlock_bh(&endpoint->target->rx_lock);
1358                        ep_cb.rx_refill(endpoint->target, endpoint->eid);
1359                        return;
1360                }
1361                spin_unlock_bh(&endpoint->target->rx_lock);
1362        }
1363}
1364
1365/* This function is called with rx_lock held */
1366static int ath6kl_htc_rx_setup(struct htc_target *target,
1367                               struct htc_endpoint *ep,
1368                               u32 *lk_ahds, struct list_head *queue, int n_msg)
1369{
1370        struct htc_packet *packet;
1371        /* FIXME: type of lk_ahds can't be right */
1372        struct htc_frame_hdr *htc_hdr = (struct htc_frame_hdr *)lk_ahds;
1373        struct htc_ep_callbacks ep_cb;
1374        int status = 0, j, full_len;
1375        bool no_recycle;
1376
1377        full_len = CALC_TXRX_PADDED_LEN(target,
1378                                        le16_to_cpu(htc_hdr->payld_len) +
1379                                        sizeof(*htc_hdr));
1380
1381        if (!htc_valid_rx_frame_len(target, ep->eid, full_len)) {
1382                ath6kl_warn("Rx buffer requested with invalid length htc_hdr:eid %d, flags 0x%x, len %d\n",
1383                            htc_hdr->eid, htc_hdr->flags,
1384                            le16_to_cpu(htc_hdr->payld_len));
1385                return -EINVAL;
1386        }
1387
1388        ep_cb = ep->ep_cb;
1389        for (j = 0; j < n_msg; j++) {
1390                /*
1391                 * Reset flag, any packets allocated using the
1392                 * rx_alloc() API cannot be recycled on
1393                 * cleanup,they must be explicitly returned.
1394                 */
1395                no_recycle = false;
1396
1397                if (ep_cb.rx_allocthresh &&
1398                    (full_len > ep_cb.rx_alloc_thresh)) {
1399                        ep->ep_st.rx_alloc_thresh_hit += 1;
1400                        ep->ep_st.rxalloc_thresh_byte +=
1401                                le16_to_cpu(htc_hdr->payld_len);
1402
1403                        spin_unlock_bh(&target->rx_lock);
1404                        no_recycle = true;
1405
1406                        packet = ep_cb.rx_allocthresh(ep->target, ep->eid,
1407                                                      full_len);
1408                        spin_lock_bh(&target->rx_lock);
1409                } else {
1410                        /* refill handler is being used */
1411                        if (list_empty(&ep->rx_bufq)) {
1412                                if (ep_cb.rx_refill) {
1413                                        spin_unlock_bh(&target->rx_lock);
1414                                        ep_cb.rx_refill(ep->target, ep->eid);
1415                                        spin_lock_bh(&target->rx_lock);
1416                                }
1417                        }
1418
1419                        if (list_empty(&ep->rx_bufq)) {
1420                                packet = NULL;
1421                        } else {
1422                                packet = list_first_entry(&ep->rx_bufq,
1423                                                struct htc_packet, list);
1424                                list_del(&packet->list);
1425                        }
1426                }
1427
1428                if (!packet) {
1429                        target->rx_st_flags |= HTC_RECV_WAIT_BUFFERS;
1430                        target->ep_waiting = ep->eid;
1431                        return -ENOSPC;
1432                }
1433
1434                /* clear flags */
1435                packet->info.rx.rx_flags = 0;
1436                packet->info.rx.indicat_flags = 0;
1437                packet->status = 0;
1438
1439                if (no_recycle)
1440                        /*
1441                         * flag that these packets cannot be
1442                         * recycled, they have to be returned to
1443                         * the user
1444                         */
1445                        packet->info.rx.rx_flags |= HTC_RX_PKT_NO_RECYCLE;
1446
1447                /* Caller needs to free this upon any failure */
1448                list_add_tail(&packet->list, queue);
1449
1450                if (target->htc_flags & HTC_OP_STATE_STOPPING) {
1451                        status = -ECANCELED;
1452                        break;
1453                }
1454
1455                if (j) {
1456                        packet->info.rx.rx_flags |= HTC_RX_PKT_REFRESH_HDR;
1457                        packet->info.rx.exp_hdr = 0xFFFFFFFF;
1458                } else
1459                        /* set expected look ahead */
1460                        packet->info.rx.exp_hdr = *lk_ahds;
1461
1462                packet->act_len = le16_to_cpu(htc_hdr->payld_len) +
1463                        HTC_HDR_LENGTH;
1464        }
1465
1466        return status;
1467}
1468
1469static int ath6kl_htc_rx_alloc(struct htc_target *target,
1470                               u32 lk_ahds[], int msg,
1471                               struct htc_endpoint *endpoint,
1472                               struct list_head *queue)
1473{
1474        int status = 0;
1475        struct htc_packet *packet, *tmp_pkt;
1476        struct htc_frame_hdr *htc_hdr;
1477        int i, n_msg;
1478
1479        spin_lock_bh(&target->rx_lock);
1480
1481        for (i = 0; i < msg; i++) {
1482                htc_hdr = (struct htc_frame_hdr *)&lk_ahds[i];
1483
1484                if (htc_hdr->eid >= ENDPOINT_MAX) {
1485                        ath6kl_err("invalid ep in look-ahead: %d\n",
1486                                   htc_hdr->eid);
1487                        status = -ENOMEM;
1488                        break;
1489                }
1490
1491                if (htc_hdr->eid != endpoint->eid) {
1492                        ath6kl_err("invalid ep in look-ahead: %d should be : %d (index:%d)\n",
1493                                   htc_hdr->eid, endpoint->eid, i);
1494                        status = -ENOMEM;
1495                        break;
1496                }
1497
1498                if (le16_to_cpu(htc_hdr->payld_len) > HTC_MAX_PAYLOAD_LENGTH) {
1499                        ath6kl_err("payload len %d exceeds max htc : %d !\n",
1500                                   htc_hdr->payld_len,
1501                                   (u32) HTC_MAX_PAYLOAD_LENGTH);
1502                        status = -ENOMEM;
1503                        break;
1504                }
1505
1506                if (endpoint->svc_id == 0) {
1507                        ath6kl_err("ep %d is not connected !\n", htc_hdr->eid);
1508                        status = -ENOMEM;
1509                        break;
1510                }
1511
1512                if (htc_hdr->flags & HTC_FLG_RX_BNDL_CNT) {
1513                        /*
1514                         * HTC header indicates that every packet to follow
1515                         * has the same padded length so that it can be
1516                         * optimally fetched as a full bundle.
1517                         */
1518                        n_msg = (htc_hdr->flags & HTC_FLG_RX_BNDL_CNT) >>
1519                                HTC_FLG_RX_BNDL_CNT_S;
1520
1521                        /* the count doesn't include the starter frame */
1522                        n_msg++;
1523                        if (n_msg > target->msg_per_bndl_max) {
1524                                status = -ENOMEM;
1525                                break;
1526                        }
1527
1528                        endpoint->ep_st.rx_bundle_from_hdr += 1;
1529                        ath6kl_dbg(ATH6KL_DBG_HTC,
1530                                   "htc rx bundle pkts %d\n",
1531                                   n_msg);
1532                } else
1533                        /* HTC header only indicates 1 message to fetch */
1534                        n_msg = 1;
1535
1536                /* Setup packet buffers for each message */
1537                status = ath6kl_htc_rx_setup(target, endpoint, &lk_ahds[i],
1538                                             queue, n_msg);
1539
1540                /*
1541                 * This is due to unavailabilty of buffers to rx entire data.
1542                 * Return no error so that free buffers from queue can be used
1543                 * to receive partial data.
1544                 */
1545                if (status == -ENOSPC) {
1546                        spin_unlock_bh(&target->rx_lock);
1547                        return 0;
1548                }
1549
1550                if (status)
1551                        break;
1552        }
1553
1554        spin_unlock_bh(&target->rx_lock);
1555
1556        if (status) {
1557                list_for_each_entry_safe(packet, tmp_pkt, queue, list) {
1558                        list_del(&packet->list);
1559                        htc_reclaim_rxbuf(target, packet,
1560                                          &target->endpoint[packet->endpoint]);
1561                }
1562        }
1563
1564        return status;
1565}
1566
1567static void htc_ctrl_rx(struct htc_target *context, struct htc_packet *packets)
1568{
1569        if (packets->endpoint != ENDPOINT_0) {
1570                WARN_ON(1);
1571                return;
1572        }
1573
1574        if (packets->status == -ECANCELED) {
1575                reclaim_rx_ctrl_buf(context, packets);
1576                return;
1577        }
1578
1579        if (packets->act_len > 0) {
1580                ath6kl_err("htc_ctrl_rx, got message with len:%zu\n",
1581                           packets->act_len + HTC_HDR_LENGTH);
1582
1583                ath6kl_dbg_dump(ATH6KL_DBG_HTC,
1584                                "htc rx unexpected endpoint 0 message", "",
1585                                packets->buf - HTC_HDR_LENGTH,
1586                                packets->act_len + HTC_HDR_LENGTH);
1587        }
1588
1589        htc_reclaim_rxbuf(context, packets, &context->endpoint[0]);
1590}
1591
1592static void htc_proc_cred_rpt(struct htc_target *target,
1593                              struct htc_credit_report *rpt,
1594                              int n_entries,
1595                              enum htc_endpoint_id from_ep)
1596{
1597        struct htc_endpoint *endpoint;
1598        int tot_credits = 0, i;
1599        bool dist = false;
1600
1601        spin_lock_bh(&target->tx_lock);
1602
1603        for (i = 0; i < n_entries; i++, rpt++) {
1604                if (rpt->eid >= ENDPOINT_MAX) {
1605                        WARN_ON(1);
1606                        spin_unlock_bh(&target->tx_lock);
1607                        return;
1608                }
1609
1610                endpoint = &target->endpoint[rpt->eid];
1611
1612                ath6kl_dbg(ATH6KL_DBG_CREDIT,
1613                           "credit report ep %d credits %d\n",
1614                           rpt->eid, rpt->credits);
1615
1616                endpoint->ep_st.tx_cred_rpt += 1;
1617                endpoint->ep_st.cred_retnd += rpt->credits;
1618
1619                if (from_ep == rpt->eid) {
1620                        /*
1621                         * This credit report arrived on the same endpoint
1622                         * indicating it arrived in an RX packet.
1623                         */
1624                        endpoint->ep_st.cred_from_rx += rpt->credits;
1625                        endpoint->ep_st.cred_rpt_from_rx += 1;
1626                } else if (from_ep == ENDPOINT_0) {
1627                        /* credit arrived on endpoint 0 as a NULL message */
1628                        endpoint->ep_st.cred_from_ep0 += rpt->credits;
1629                        endpoint->ep_st.cred_rpt_ep0 += 1;
1630                } else {
1631                        endpoint->ep_st.cred_from_other += rpt->credits;
1632                        endpoint->ep_st.cred_rpt_from_other += 1;
1633                }
1634
1635                if (rpt->eid == ENDPOINT_0)
1636                        /* always give endpoint 0 credits back */
1637                        endpoint->cred_dist.credits += rpt->credits;
1638                else {
1639                        endpoint->cred_dist.cred_to_dist += rpt->credits;
1640                        dist = true;
1641                }
1642
1643                /*
1644                 * Refresh tx depth for distribution function that will
1645                 * recover these credits NOTE: this is only valid when
1646                 * there are credits to recover!
1647                 */
1648                endpoint->cred_dist.txq_depth =
1649                        get_queue_depth(&endpoint->txq);
1650
1651                tot_credits += rpt->credits;
1652        }
1653
1654        if (dist) {
1655                /*
1656                 * This was a credit return based on a completed send
1657                 * operations note, this is done with the lock held
1658                 */
1659                ath6kl_credit_distribute(target->credit_info,
1660                                         &target->cred_dist_list,
1661                                         HTC_CREDIT_DIST_SEND_COMPLETE);
1662        }
1663
1664        spin_unlock_bh(&target->tx_lock);
1665
1666        if (tot_credits)
1667                htc_chk_ep_txq(target);
1668}
1669
1670static int htc_parse_trailer(struct htc_target *target,
1671                             struct htc_record_hdr *record,
1672                             u8 *record_buf, u32 *next_lk_ahds,
1673                             enum htc_endpoint_id endpoint,
1674                             int *n_lk_ahds)
1675{
1676        struct htc_bundle_lkahd_rpt *bundle_lkahd_rpt;
1677        struct htc_lookahead_report *lk_ahd;
1678        int len;
1679
1680        switch (record->rec_id) {
1681        case HTC_RECORD_CREDITS:
1682                len = record->len / sizeof(struct htc_credit_report);
1683                if (!len) {
1684                        WARN_ON(1);
1685                        return -EINVAL;
1686                }
1687
1688                htc_proc_cred_rpt(target,
1689                                  (struct htc_credit_report *) record_buf,
1690                                  len, endpoint);
1691                break;
1692        case HTC_RECORD_LOOKAHEAD:
1693                len = record->len / sizeof(*lk_ahd);
1694                if (!len) {
1695                        WARN_ON(1);
1696                        return -EINVAL;
1697                }
1698
1699                lk_ahd = (struct htc_lookahead_report *) record_buf;
1700                if ((lk_ahd->pre_valid == ((~lk_ahd->post_valid) & 0xFF)) &&
1701                    next_lk_ahds) {
1702                        ath6kl_dbg(ATH6KL_DBG_HTC,
1703                                   "htc rx lk_ahd found pre_valid 0x%x post_valid 0x%x\n",
1704                                   lk_ahd->pre_valid, lk_ahd->post_valid);
1705
1706                        /* look ahead bytes are valid, copy them over */
1707                        memcpy((u8 *)&next_lk_ahds[0], lk_ahd->lk_ahd, 4);
1708
1709                        ath6kl_dbg_dump(ATH6KL_DBG_HTC,
1710                                        "htc rx next look ahead",
1711                                        "", next_lk_ahds, 4);
1712
1713                        *n_lk_ahds = 1;
1714                }
1715                break;
1716        case HTC_RECORD_LOOKAHEAD_BUNDLE:
1717                len = record->len / sizeof(*bundle_lkahd_rpt);
1718                if (!len || (len > HTC_HOST_MAX_MSG_PER_BUNDLE)) {
1719                        WARN_ON(1);
1720                        return -EINVAL;
1721                }
1722
1723                if (next_lk_ahds) {
1724                        int i;
1725
1726                        bundle_lkahd_rpt =
1727                                (struct htc_bundle_lkahd_rpt *) record_buf;
1728
1729                        ath6kl_dbg_dump(ATH6KL_DBG_HTC, "htc rx bundle lk_ahd",
1730                                        "", record_buf, record->len);
1731
1732                        for (i = 0; i < len; i++) {
1733                                memcpy((u8 *)&next_lk_ahds[i],
1734                                       bundle_lkahd_rpt->lk_ahd, 4);
1735                                bundle_lkahd_rpt++;
1736                        }
1737
1738                        *n_lk_ahds = i;
1739                }
1740                break;
1741        default:
1742                ath6kl_err("unhandled record: id:%d len:%d\n",
1743                           record->rec_id, record->len);
1744                break;
1745        }
1746
1747        return 0;
1748}
1749
1750static int htc_proc_trailer(struct htc_target *target,
1751                            u8 *buf, int len, u32 *next_lk_ahds,
1752                            int *n_lk_ahds, enum htc_endpoint_id endpoint)
1753{
1754        struct htc_record_hdr *record;
1755        int orig_len;
1756        int status;
1757        u8 *record_buf;
1758        u8 *orig_buf;
1759
1760        ath6kl_dbg(ATH6KL_DBG_HTC, "htc rx trailer len %d\n", len);
1761        ath6kl_dbg_dump(ATH6KL_DBG_HTC, NULL, "", buf, len);
1762
1763        orig_buf = buf;
1764        orig_len = len;
1765        status = 0;
1766
1767        while (len > 0) {
1768                if (len < sizeof(struct htc_record_hdr)) {
1769                        status = -ENOMEM;
1770                        break;
1771                }
1772                /* these are byte aligned structs */
1773                record = (struct htc_record_hdr *) buf;
1774                len -= sizeof(struct htc_record_hdr);
1775                buf += sizeof(struct htc_record_hdr);
1776
1777                if (record->len > len) {
1778                        ath6kl_err("invalid record len: %d (id:%d) buf has: %d bytes left\n",
1779                                   record->len, record->rec_id, len);
1780                        status = -ENOMEM;
1781                        break;
1782                }
1783                record_buf = buf;
1784
1785                status = htc_parse_trailer(target, record, record_buf,
1786                                           next_lk_ahds, endpoint, n_lk_ahds);
1787
1788                if (status)
1789                        break;
1790
1791                /* advance buffer past this record for next time around */
1792                buf += record->len;
1793                len -= record->len;
1794        }
1795
1796        if (status)
1797                ath6kl_dbg_dump(ATH6KL_DBG_HTC, "htc rx bad trailer",
1798                                "", orig_buf, orig_len);
1799
1800        return status;
1801}
1802
1803static int ath6kl_htc_rx_process_hdr(struct htc_target *target,
1804                                     struct htc_packet *packet,
1805                                     u32 *next_lkahds, int *n_lkahds)
1806{
1807        int status = 0;
1808        u16 payload_len;
1809        u32 lk_ahd;
1810        struct htc_frame_hdr *htc_hdr = (struct htc_frame_hdr *)packet->buf;
1811
1812        if (n_lkahds != NULL)
1813                *n_lkahds = 0;
1814
1815        /*
1816         * NOTE: we cannot assume the alignment of buf, so we use the safe
1817         * macros to retrieve 16 bit fields.
1818         */
1819        payload_len = le16_to_cpu(get_unaligned(&htc_hdr->payld_len));
1820
1821        memcpy((u8 *)&lk_ahd, packet->buf, sizeof(lk_ahd));
1822
1823        if (packet->info.rx.rx_flags & HTC_RX_PKT_REFRESH_HDR) {
1824                /*
1825                 * Refresh the expected header and the actual length as it
1826                 * was unknown when this packet was grabbed as part of the
1827                 * bundle.
1828                 */
1829                packet->info.rx.exp_hdr = lk_ahd;
1830                packet->act_len = payload_len + HTC_HDR_LENGTH;
1831
1832                /* validate the actual header that was refreshed  */
1833                if (packet->act_len > packet->buf_len) {
1834                        ath6kl_err("refreshed hdr payload len (%d) in bundled recv is invalid (hdr: 0x%X)\n",
1835                                   payload_len, lk_ahd);
1836                        /*
1837                         * Limit this to max buffer just to print out some
1838                         * of the buffer.
1839                         */
1840                        packet->act_len = min(packet->act_len, packet->buf_len);
1841                        status = -ENOMEM;
1842                        goto fail_rx;
1843                }
1844
1845                if (packet->endpoint != htc_hdr->eid) {
1846                        ath6kl_err("refreshed hdr ep (%d) does not match expected ep (%d)\n",
1847                                   htc_hdr->eid, packet->endpoint);
1848                        status = -ENOMEM;
1849                        goto fail_rx;
1850                }
1851        }
1852
1853        if (lk_ahd != packet->info.rx.exp_hdr) {
1854                ath6kl_err("%s(): lk_ahd mismatch! (pPkt:0x%p flags:0x%X)\n",
1855                           __func__, packet, packet->info.rx.rx_flags);
1856                ath6kl_dbg_dump(ATH6KL_DBG_HTC, "htc rx expected lk_ahd",
1857                                "", &packet->info.rx.exp_hdr, 4);
1858                ath6kl_dbg_dump(ATH6KL_DBG_HTC, "htc rx current header",
1859                                "", (u8 *)&lk_ahd, sizeof(lk_ahd));
1860                status = -ENOMEM;
1861                goto fail_rx;
1862        }
1863
1864        if (htc_hdr->flags & HTC_FLG_RX_TRAILER) {
1865                if (htc_hdr->ctrl[0] < sizeof(struct htc_record_hdr) ||
1866                    htc_hdr->ctrl[0] > payload_len) {
1867                        ath6kl_err("%s(): invalid hdr (payload len should be :%d, CB[0] is:%d)\n",
1868                                   __func__, payload_len, htc_hdr->ctrl[0]);
1869                        status = -ENOMEM;
1870                        goto fail_rx;
1871                }
1872
1873                if (packet->info.rx.rx_flags & HTC_RX_PKT_IGNORE_LOOKAHEAD) {
1874                        next_lkahds = NULL;
1875                        n_lkahds = NULL;
1876                }
1877
1878                status = htc_proc_trailer(target, packet->buf + HTC_HDR_LENGTH
1879                                          + payload_len - htc_hdr->ctrl[0],
1880                                          htc_hdr->ctrl[0], next_lkahds,
1881                                           n_lkahds, packet->endpoint);
1882
1883                if (status)
1884                        goto fail_rx;
1885
1886                packet->act_len -= htc_hdr->ctrl[0];
1887        }
1888
1889        packet->buf += HTC_HDR_LENGTH;
1890        packet->act_len -= HTC_HDR_LENGTH;
1891
1892fail_rx:
1893        if (status)
1894                ath6kl_dbg_dump(ATH6KL_DBG_HTC, "htc rx bad packet",
1895                                "", packet->buf, packet->act_len);
1896
1897        return status;
1898}
1899
1900static void ath6kl_htc_rx_complete(struct htc_endpoint *endpoint,
1901                                   struct htc_packet *packet)
1902{
1903                ath6kl_dbg(ATH6KL_DBG_HTC,
1904                           "htc rx complete ep %d packet 0x%p\n",
1905                           endpoint->eid, packet);
1906
1907                endpoint->ep_cb.rx(endpoint->target, packet);
1908}
1909
1910static int ath6kl_htc_rx_bundle(struct htc_target *target,
1911                                struct list_head *rxq,
1912                                struct list_head *sync_compq,
1913                                int *n_pkt_fetched, bool part_bundle)
1914{
1915        struct hif_scatter_req *scat_req;
1916        struct htc_packet *packet;
1917        int rem_space = target->max_rx_bndl_sz;
1918        int n_scat_pkt, status = 0, i, len;
1919
1920        n_scat_pkt = get_queue_depth(rxq);
1921        n_scat_pkt = min(n_scat_pkt, target->msg_per_bndl_max);
1922
1923        if ((get_queue_depth(rxq) - n_scat_pkt) > 0) {
1924                /*
1925                 * We were forced to split this bundle receive operation
1926                 * all packets in this partial bundle must have their
1927                 * lookaheads ignored.
1928                 */
1929                part_bundle = true;
1930
1931                /*
1932                 * This would only happen if the target ignored our max
1933                 * bundle limit.
1934                 */
1935                ath6kl_warn("%s(): partial bundle detected num:%d , %d\n",
1936                            __func__, get_queue_depth(rxq), n_scat_pkt);
1937        }
1938
1939        len = 0;
1940
1941        ath6kl_dbg(ATH6KL_DBG_HTC,
1942                   "htc rx bundle depth %d pkts %d\n",
1943                   get_queue_depth(rxq), n_scat_pkt);
1944
1945        scat_req = hif_scatter_req_get(target->dev->ar);
1946
1947        if (scat_req == NULL)
1948                goto fail_rx_pkt;
1949
1950        for (i = 0; i < n_scat_pkt; i++) {
1951                int pad_len;
1952
1953                packet = list_first_entry(rxq, struct htc_packet, list);
1954                list_del(&packet->list);
1955
1956                pad_len = CALC_TXRX_PADDED_LEN(target,
1957                                                   packet->act_len);
1958
1959                if ((rem_space - pad_len) < 0) {
1960                        list_add(&packet->list, rxq);
1961                        break;
1962                }
1963
1964                rem_space -= pad_len;
1965
1966                if (part_bundle || (i < (n_scat_pkt - 1)))
1967                        /*
1968                         * Packet 0..n-1 cannot be checked for look-aheads
1969                         * since we are fetching a bundle the last packet
1970                         * however can have it's lookahead used
1971                         */
1972                        packet->info.rx.rx_flags |=
1973                            HTC_RX_PKT_IGNORE_LOOKAHEAD;
1974
1975                /* NOTE: 1 HTC packet per scatter entry */
1976                scat_req->scat_list[i].buf = packet->buf;
1977                scat_req->scat_list[i].len = pad_len;
1978
1979                packet->info.rx.rx_flags |= HTC_RX_PKT_PART_OF_BUNDLE;
1980
1981                list_add_tail(&packet->list, sync_compq);
1982
1983                WARN_ON(!scat_req->scat_list[i].len);
1984                len += scat_req->scat_list[i].len;
1985        }
1986
1987        scat_req->len = len;
1988        scat_req->scat_entries = i;
1989
1990        status = ath6kl_hif_submit_scat_req(target->dev, scat_req, true);
1991
1992        if (!status)
1993                *n_pkt_fetched = i;
1994
1995        /* free scatter request */
1996        hif_scatter_req_add(target->dev->ar, scat_req);
1997
1998fail_rx_pkt:
1999
2000        return status;
2001}
2002
2003static int ath6kl_htc_rx_process_packets(struct htc_target *target,
2004                                         struct list_head *comp_pktq,
2005                                         u32 lk_ahds[],
2006                                         int *n_lk_ahd)
2007{
2008        struct htc_packet *packet, *tmp_pkt;
2009        struct htc_endpoint *ep;
2010        int status = 0;
2011
2012        list_for_each_entry_safe(packet, tmp_pkt, comp_pktq, list) {
2013                ep = &target->endpoint[packet->endpoint];
2014
2015                trace_ath6kl_htc_rx(packet->status, packet->endpoint,
2016                                    packet->buf, packet->act_len);
2017
2018                /* process header for each of the recv packet */
2019                status = ath6kl_htc_rx_process_hdr(target, packet, lk_ahds,
2020                                                   n_lk_ahd);
2021                if (status)
2022                        return status;
2023
2024                list_del(&packet->list);
2025
2026                if (list_empty(comp_pktq)) {
2027                        /*
2028                         * Last packet's more packet flag is set
2029                         * based on the lookahead.
2030                         */
2031                        if (*n_lk_ahd > 0)
2032                                ath6kl_htc_rx_set_indicate(lk_ahds[0],
2033                                                           ep, packet);
2034                } else
2035                        /*
2036                         * Packets in a bundle automatically have
2037                         * this flag set.
2038                         */
2039                        packet->info.rx.indicat_flags |=
2040                                HTC_RX_FLAGS_INDICATE_MORE_PKTS;
2041
2042                ath6kl_htc_rx_update_stats(ep, *n_lk_ahd);
2043
2044                if (packet->info.rx.rx_flags & HTC_RX_PKT_PART_OF_BUNDLE)
2045                        ep->ep_st.rx_bundl += 1;
2046
2047                ath6kl_htc_rx_complete(ep, packet);
2048        }
2049
2050        return status;
2051}
2052
2053static int ath6kl_htc_rx_fetch(struct htc_target *target,
2054                               struct list_head *rx_pktq,
2055                               struct list_head *comp_pktq)
2056{
2057        int fetched_pkts;
2058        bool part_bundle = false;
2059        int status = 0;
2060        struct list_head tmp_rxq;
2061        struct htc_packet *packet, *tmp_pkt;
2062
2063        /* now go fetch the list of HTC packets */
2064        while (!list_empty(rx_pktq)) {
2065                fetched_pkts = 0;
2066
2067                INIT_LIST_HEAD(&tmp_rxq);
2068
2069                if (target->rx_bndl_enable && (get_queue_depth(rx_pktq) > 1)) {
2070                        /*
2071                         * There are enough packets to attempt a
2072                         * bundle transfer and recv bundling is
2073                         * allowed.
2074                         */
2075                        status = ath6kl_htc_rx_bundle(target, rx_pktq,
2076                                                      &tmp_rxq,
2077                                                      &fetched_pkts,
2078                                                      part_bundle);
2079                        if (status)
2080                                goto fail_rx;
2081
2082                        if (!list_empty(rx_pktq))
2083                                part_bundle = true;
2084
2085                        list_splice_tail_init(&tmp_rxq, comp_pktq);
2086                }
2087
2088                if (!fetched_pkts) {
2089                        packet = list_first_entry(rx_pktq, struct htc_packet,
2090                                                   list);
2091
2092                        /* fully synchronous */
2093                        packet->completion = NULL;
2094
2095                        if (!list_is_singular(rx_pktq))
2096                                /*
2097                                 * look_aheads in all packet
2098                                 * except the last one in the
2099                                 * bundle must be ignored
2100                                 */
2101                                packet->info.rx.rx_flags |=
2102                                        HTC_RX_PKT_IGNORE_LOOKAHEAD;
2103
2104                        /* go fetch the packet */
2105                        status = ath6kl_htc_rx_packet(target, packet,
2106                                                      packet->act_len);
2107
2108                        list_move_tail(&packet->list, &tmp_rxq);
2109
2110                        if (status)
2111                                goto fail_rx;
2112
2113                        list_splice_tail_init(&tmp_rxq, comp_pktq);
2114                }
2115        }
2116
2117        return 0;
2118
2119fail_rx:
2120
2121        /*
2122         * Cleanup any packets we allocated but didn't use to
2123         * actually fetch any packets.
2124         */
2125
2126        list_for_each_entry_safe(packet, tmp_pkt, rx_pktq, list) {
2127                list_del(&packet->list);
2128                htc_reclaim_rxbuf(target, packet,
2129                                  &target->endpoint[packet->endpoint]);
2130        }
2131
2132        list_for_each_entry_safe(packet, tmp_pkt, &tmp_rxq, list) {
2133                list_del(&packet->list);
2134                htc_reclaim_rxbuf(target, packet,
2135                                  &target->endpoint[packet->endpoint]);
2136        }
2137
2138        return status;
2139}
2140
2141int ath6kl_htc_rxmsg_pending_handler(struct htc_target *target,
2142                                     u32 msg_look_ahead, int *num_pkts)
2143{
2144        struct htc_packet *packets, *tmp_pkt;
2145        struct htc_endpoint *endpoint;
2146        struct list_head rx_pktq, comp_pktq;
2147        int status = 0;
2148        u32 look_aheads[HTC_HOST_MAX_MSG_PER_BUNDLE];
2149        int num_look_ahead = 1;
2150        enum htc_endpoint_id id;
2151        int n_fetched = 0;
2152
2153        INIT_LIST_HEAD(&comp_pktq);
2154        *num_pkts = 0;
2155
2156        /*
2157         * On first entry copy the look_aheads into our temp array for
2158         * processing
2159         */
2160        look_aheads[0] = msg_look_ahead;
2161
2162        while (true) {
2163                /*
2164                 * First lookahead sets the expected endpoint IDs for all
2165                 * packets in a bundle.
2166                 */
2167                id = ((struct htc_frame_hdr *)&look_aheads[0])->eid;
2168                endpoint = &target->endpoint[id];
2169
2170                if (id >= ENDPOINT_MAX) {
2171                        ath6kl_err("MsgPend, invalid endpoint in look-ahead: %d\n",
2172                                   id);
2173                        status = -ENOMEM;
2174                        break;
2175                }
2176
2177                INIT_LIST_HEAD(&rx_pktq);
2178                INIT_LIST_HEAD(&comp_pktq);
2179
2180                /*
2181                 * Try to allocate as many HTC RX packets indicated by the
2182                 * look_aheads.
2183                 */
2184                status = ath6kl_htc_rx_alloc(target, look_aheads,
2185                                             num_look_ahead, endpoint,
2186                                             &rx_pktq);
2187                if (status)
2188                        break;
2189
2190                if (get_queue_depth(&rx_pktq) >= 2)
2191                        /*
2192                         * A recv bundle was detected, force IRQ status
2193                         * re-check again
2194                         */
2195                        target->chk_irq_status_cnt = 1;
2196
2197                n_fetched += get_queue_depth(&rx_pktq);
2198
2199                num_look_ahead = 0;
2200
2201                status = ath6kl_htc_rx_fetch(target, &rx_pktq, &comp_pktq);
2202
2203                if (!status)
2204                        ath6kl_htc_rx_chk_water_mark(endpoint);
2205
2206                /* Process fetched packets */
2207                status = ath6kl_htc_rx_process_packets(target, &comp_pktq,
2208                                                       look_aheads,
2209                                                       &num_look_ahead);
2210
2211                if (!num_look_ahead || status)
2212                        break;
2213
2214                /*
2215                 * For SYNCH processing, if we get here, we are running
2216                 * through the loop again due to a detected lookahead. Set
2217                 * flag that we should re-check IRQ status registers again
2218                 * before leaving IRQ processing, this can net better
2219                 * performance in high throughput situations.
2220                 */
2221                target->chk_irq_status_cnt = 1;
2222        }
2223
2224        if (status) {
2225                if (status != -ECANCELED)
2226                        ath6kl_err("failed to get pending recv messages: %d\n",
2227                                   status);
2228
2229                /* cleanup any packets in sync completion queue */
2230                list_for_each_entry_safe(packets, tmp_pkt, &comp_pktq, list) {
2231                        list_del(&packets->list);
2232                        htc_reclaim_rxbuf(target, packets,
2233                                          &target->endpoint[packets->endpoint]);
2234                }
2235
2236                if (target->htc_flags & HTC_OP_STATE_STOPPING) {
2237                        ath6kl_warn("host is going to stop blocking receiver for htc_stop\n");
2238                        ath6kl_hif_rx_control(target->dev, false);
2239                }
2240        }
2241
2242        /*
2243         * Before leaving, check to see if host ran out of buffers and
2244         * needs to stop the receiver.
2245         */
2246        if (target->rx_st_flags & HTC_RECV_WAIT_BUFFERS) {
2247                ath6kl_warn("host has no rx buffers blocking receiver to prevent overrun\n");
2248                ath6kl_hif_rx_control(target->dev, false);
2249        }
2250        *num_pkts = n_fetched;
2251
2252        return status;
2253}
2254
2255/*
2256 * Synchronously wait for a control message from the target,
2257 * This function is used at initialization time ONLY.  At init messages
2258 * on ENDPOINT 0 are expected.
2259 */
2260static struct htc_packet *htc_wait_for_ctrl_msg(struct htc_target *target)
2261{
2262        struct htc_packet *packet = NULL;
2263        struct htc_frame_hdr *htc_hdr;
2264        u32 look_ahead;
2265
2266        if (ath6kl_hif_poll_mboxmsg_rx(target->dev, &look_ahead,
2267                                       HTC_TARGET_RESPONSE_TIMEOUT))
2268                return NULL;
2269
2270        ath6kl_dbg(ATH6KL_DBG_HTC,
2271                   "htc rx wait ctrl look_ahead 0x%X\n", look_ahead);
2272
2273        htc_hdr = (struct htc_frame_hdr *)&look_ahead;
2274
2275        if (htc_hdr->eid != ENDPOINT_0)
2276                return NULL;
2277
2278        packet = htc_get_control_buf(target, false);
2279
2280        if (!packet)
2281                return NULL;
2282
2283        packet->info.rx.rx_flags = 0;
2284        packet->info.rx.exp_hdr = look_ahead;
2285        packet->act_len = le16_to_cpu(htc_hdr->payld_len) + HTC_HDR_LENGTH;
2286
2287        if (packet->act_len > packet->buf_len)
2288                goto fail_ctrl_rx;
2289
2290        /* we want synchronous operation */
2291        packet->completion = NULL;
2292
2293        /* get the message from the device, this will block */
2294        if (ath6kl_htc_rx_packet(target, packet, packet->act_len))
2295                goto fail_ctrl_rx;
2296
2297        trace_ath6kl_htc_rx(packet->status, packet->endpoint,
2298                            packet->buf, packet->act_len);
2299
2300        /* process receive header */
2301        packet->status = ath6kl_htc_rx_process_hdr(target, packet, NULL, NULL);
2302
2303        if (packet->status) {
2304                ath6kl_err("htc_wait_for_ctrl_msg, ath6kl_htc_rx_process_hdr failed (status = %d)\n",
2305                           packet->status);
2306                goto fail_ctrl_rx;
2307        }
2308
2309        return packet;
2310
2311fail_ctrl_rx:
2312        if (packet != NULL) {
2313                htc_rxpkt_reset(packet);
2314                reclaim_rx_ctrl_buf(target, packet);
2315        }
2316
2317        return NULL;
2318}
2319
2320static int ath6kl_htc_mbox_add_rxbuf_multiple(struct htc_target *target,
2321                                  struct list_head *pkt_queue)
2322{
2323        struct htc_endpoint *endpoint;
2324        struct htc_packet *first_pkt;
2325        bool rx_unblock = false;
2326        int status = 0, depth;
2327
2328        if (list_empty(pkt_queue))
2329                return -ENOMEM;
2330
2331        first_pkt = list_first_entry(pkt_queue, struct htc_packet, list);
2332
2333        if (first_pkt->endpoint >= ENDPOINT_MAX)
2334                return status;
2335
2336        depth = get_queue_depth(pkt_queue);
2337
2338        ath6kl_dbg(ATH6KL_DBG_HTC,
2339                   "htc rx add multiple ep id %d cnt %d len %d\n",
2340                first_pkt->endpoint, depth, first_pkt->buf_len);
2341
2342        endpoint = &target->endpoint[first_pkt->endpoint];
2343
2344        if (target->htc_flags & HTC_OP_STATE_STOPPING) {
2345                struct htc_packet *packet, *tmp_pkt;
2346
2347                /* walk through queue and mark each one canceled */
2348                list_for_each_entry_safe(packet, tmp_pkt, pkt_queue, list) {
2349                        packet->status = -ECANCELED;
2350                        list_del(&packet->list);
2351                        ath6kl_htc_rx_complete(endpoint, packet);
2352                }
2353
2354                return status;
2355        }
2356
2357        spin_lock_bh(&target->rx_lock);
2358
2359        list_splice_tail_init(pkt_queue, &endpoint->rx_bufq);
2360
2361        /* check if we are blocked waiting for a new buffer */
2362        if (target->rx_st_flags & HTC_RECV_WAIT_BUFFERS) {
2363                if (target->ep_waiting == first_pkt->endpoint) {
2364                        ath6kl_dbg(ATH6KL_DBG_HTC,
2365                                   "htc rx blocked on ep %d, unblocking\n",
2366                                   target->ep_waiting);
2367                        target->rx_st_flags &= ~HTC_RECV_WAIT_BUFFERS;
2368                        target->ep_waiting = ENDPOINT_MAX;
2369                        rx_unblock = true;
2370                }
2371        }
2372
2373        spin_unlock_bh(&target->rx_lock);
2374
2375        if (rx_unblock && !(target->htc_flags & HTC_OP_STATE_STOPPING))
2376                /* TODO : implement a buffer threshold count? */
2377                ath6kl_hif_rx_control(target->dev, true);
2378
2379        return status;
2380}
2381
2382static void ath6kl_htc_mbox_flush_rx_buf(struct htc_target *target)
2383{
2384        struct htc_endpoint *endpoint;
2385        struct htc_packet *packet, *tmp_pkt;
2386        int i;
2387
2388        for (i = ENDPOINT_0; i < ENDPOINT_MAX; i++) {
2389                endpoint = &target->endpoint[i];
2390                if (!endpoint->svc_id)
2391                        /* not in use.. */
2392                        continue;
2393
2394                spin_lock_bh(&target->rx_lock);
2395                list_for_each_entry_safe(packet, tmp_pkt,
2396                                         &endpoint->rx_bufq, list) {
2397                        list_del(&packet->list);
2398                        spin_unlock_bh(&target->rx_lock);
2399                        ath6kl_dbg(ATH6KL_DBG_HTC,
2400                                   "htc rx flush pkt 0x%p  len %d  ep %d\n",
2401                                   packet, packet->buf_len,
2402                                   packet->endpoint);
2403                        /*
2404                         * packets in rx_bufq of endpoint 0 have originally
2405                         * been queued from target->free_ctrl_rxbuf where
2406                         * packet and packet->buf_start are allocated
2407                         * separately using kmalloc(). For other endpoint
2408                         * rx_bufq, it is allocated as skb where packet is
2409                         * skb->head. Take care of this difference while freeing
2410                         * the memory.
2411                         */
2412                        if (packet->endpoint == ENDPOINT_0) {
2413                                kfree(packet->buf_start);
2414                                kfree(packet);
2415                        } else {
2416                                dev_kfree_skb(packet->pkt_cntxt);
2417                        }
2418                        spin_lock_bh(&target->rx_lock);
2419                }
2420                spin_unlock_bh(&target->rx_lock);
2421        }
2422}
2423
2424static int ath6kl_htc_mbox_conn_service(struct htc_target *target,
2425                            struct htc_service_connect_req *conn_req,
2426                            struct htc_service_connect_resp *conn_resp)
2427{
2428        struct htc_packet *rx_pkt = NULL;
2429        struct htc_packet *tx_pkt = NULL;
2430        struct htc_conn_service_resp *resp_msg;
2431        struct htc_conn_service_msg *conn_msg;
2432        struct htc_endpoint *endpoint;
2433        enum htc_endpoint_id assigned_ep = ENDPOINT_MAX;
2434        unsigned int max_msg_sz = 0;
2435        int status = 0;
2436        u16 msg_id;
2437
2438        ath6kl_dbg(ATH6KL_DBG_HTC,
2439                   "htc connect service target 0x%p service id 0x%x\n",
2440                   target, conn_req->svc_id);
2441
2442        if (conn_req->svc_id == HTC_CTRL_RSVD_SVC) {
2443                /* special case for pseudo control service */
2444                assigned_ep = ENDPOINT_0;
2445                max_msg_sz = HTC_MAX_CTRL_MSG_LEN;
2446        } else {
2447                /* allocate a packet to send to the target */
2448                tx_pkt = htc_get_control_buf(target, true);
2449
2450                if (!tx_pkt)
2451                        return -ENOMEM;
2452
2453                conn_msg = (struct htc_conn_service_msg *)tx_pkt->buf;
2454                memset(conn_msg, 0, sizeof(*conn_msg));
2455                conn_msg->msg_id = cpu_to_le16(HTC_MSG_CONN_SVC_ID);
2456                conn_msg->svc_id = cpu_to_le16(conn_req->svc_id);
2457                conn_msg->conn_flags = cpu_to_le16(conn_req->conn_flags);
2458
2459                set_htc_pkt_info(tx_pkt, NULL, (u8 *) conn_msg,
2460                                 sizeof(*conn_msg) + conn_msg->svc_meta_len,
2461                                 ENDPOINT_0, HTC_SERVICE_TX_PACKET_TAG);
2462
2463                /* we want synchronous operation */
2464                tx_pkt->completion = NULL;
2465                ath6kl_htc_tx_prep_pkt(tx_pkt, 0, 0, 0);
2466                status = ath6kl_htc_tx_issue(target, tx_pkt);
2467
2468                if (status)
2469                        goto fail_tx;
2470
2471                /* wait for response */
2472                rx_pkt = htc_wait_for_ctrl_msg(target);
2473
2474                if (!rx_pkt) {
2475                        status = -ENOMEM;
2476                        goto fail_tx;
2477                }
2478
2479                resp_msg = (struct htc_conn_service_resp *)rx_pkt->buf;
2480                msg_id = le16_to_cpu(resp_msg->msg_id);
2481
2482                if ((msg_id != HTC_MSG_CONN_SVC_RESP_ID) ||
2483                    (rx_pkt->act_len < sizeof(*resp_msg))) {
2484                        status = -ENOMEM;
2485                        goto fail_tx;
2486                }
2487
2488                conn_resp->resp_code = resp_msg->status;
2489                /* check response status */
2490                if (resp_msg->status != HTC_SERVICE_SUCCESS) {
2491                        ath6kl_err("target failed service 0x%X connect request (status:%d)\n",
2492                                   resp_msg->svc_id, resp_msg->status);
2493                        status = -ENOMEM;
2494                        goto fail_tx;
2495                }
2496
2497                assigned_ep = (enum htc_endpoint_id)resp_msg->eid;
2498                max_msg_sz = le16_to_cpu(resp_msg->max_msg_sz);
2499        }
2500
2501        if (WARN_ON_ONCE(assigned_ep == ENDPOINT_UNUSED ||
2502                         assigned_ep >= ENDPOINT_MAX || !max_msg_sz)) {
2503                status = -ENOMEM;
2504                goto fail_tx;
2505        }
2506
2507        endpoint = &target->endpoint[assigned_ep];
2508        endpoint->eid = assigned_ep;
2509        if (endpoint->svc_id) {
2510                status = -ENOMEM;
2511                goto fail_tx;
2512        }
2513
2514        /* return assigned endpoint to caller */
2515        conn_resp->endpoint = assigned_ep;
2516        conn_resp->len_max = max_msg_sz;
2517
2518        /* setup the endpoint */
2519
2520        /* this marks the endpoint in use */
2521        endpoint->svc_id = conn_req->svc_id;
2522
2523        endpoint->max_txq_depth = conn_req->max_txq_depth;
2524        endpoint->len_max = max_msg_sz;
2525        endpoint->ep_cb = conn_req->ep_cb;
2526        endpoint->cred_dist.svc_id = conn_req->svc_id;
2527        endpoint->cred_dist.htc_ep = endpoint;
2528        endpoint->cred_dist.endpoint = assigned_ep;
2529        endpoint->cred_dist.cred_sz = target->tgt_cred_sz;
2530
2531        switch (endpoint->svc_id) {
2532        case WMI_DATA_BK_SVC:
2533                endpoint->tx_drop_packet_threshold = MAX_DEF_COOKIE_NUM / 3;
2534                break;
2535        default:
2536                endpoint->tx_drop_packet_threshold = MAX_HI_COOKIE_NUM;
2537                break;
2538        }
2539
2540        if (conn_req->max_rxmsg_sz) {
2541                /*
2542                 * Override cred_per_msg calculation, this optimizes
2543                 * the credit-low indications since the host will actually
2544                 * issue smaller messages in the Send path.
2545                 */
2546                if (conn_req->max_rxmsg_sz > max_msg_sz) {
2547                        status = -ENOMEM;
2548                        goto fail_tx;
2549                }
2550                endpoint->cred_dist.cred_per_msg =
2551                    conn_req->max_rxmsg_sz / target->tgt_cred_sz;
2552        } else
2553                endpoint->cred_dist.cred_per_msg =
2554                    max_msg_sz / target->tgt_cred_sz;
2555
2556        if (!endpoint->cred_dist.cred_per_msg)
2557                endpoint->cred_dist.cred_per_msg = 1;
2558
2559        /* save local connection flags */
2560        endpoint->conn_flags = conn_req->flags;
2561
2562fail_tx:
2563        if (tx_pkt)
2564                htc_reclaim_txctrl_buf(target, tx_pkt);
2565
2566        if (rx_pkt) {
2567                htc_rxpkt_reset(rx_pkt);
2568                reclaim_rx_ctrl_buf(target, rx_pkt);
2569        }
2570
2571        return status;
2572}
2573
2574static void reset_ep_state(struct htc_target *target)
2575{
2576        struct htc_endpoint *endpoint;
2577        int i;
2578
2579        for (i = ENDPOINT_0; i < ENDPOINT_MAX; i++) {
2580                endpoint = &target->endpoint[i];
2581                memset(&endpoint->cred_dist, 0, sizeof(endpoint->cred_dist));
2582                endpoint->svc_id = 0;
2583                endpoint->len_max = 0;
2584                endpoint->max_txq_depth = 0;
2585                memset(&endpoint->ep_st, 0,
2586                       sizeof(endpoint->ep_st));
2587                INIT_LIST_HEAD(&endpoint->rx_bufq);
2588                INIT_LIST_HEAD(&endpoint->txq);
2589                endpoint->target = target;
2590        }
2591
2592        /* reset distribution list */
2593        /* FIXME: free existing entries */
2594        INIT_LIST_HEAD(&target->cred_dist_list);
2595}
2596
2597static int ath6kl_htc_mbox_get_rxbuf_num(struct htc_target *target,
2598                             enum htc_endpoint_id endpoint)
2599{
2600        int num;
2601
2602        spin_lock_bh(&target->rx_lock);
2603        num = get_queue_depth(&(target->endpoint[endpoint].rx_bufq));
2604        spin_unlock_bh(&target->rx_lock);
2605        return num;
2606}
2607
2608static void htc_setup_msg_bndl(struct htc_target *target)
2609{
2610        /* limit what HTC can handle */
2611        target->msg_per_bndl_max = min(HTC_HOST_MAX_MSG_PER_BUNDLE,
2612                                       target->msg_per_bndl_max);
2613
2614        if (ath6kl_hif_enable_scatter(target->dev->ar)) {
2615                target->msg_per_bndl_max = 0;
2616                return;
2617        }
2618
2619        /* limit bundle what the device layer can handle */
2620        target->msg_per_bndl_max = min(target->max_scat_entries,
2621                                       target->msg_per_bndl_max);
2622
2623        ath6kl_dbg(ATH6KL_DBG_BOOT,
2624                   "htc bundling allowed msg_per_bndl_max %d\n",
2625                   target->msg_per_bndl_max);
2626
2627        /* Max rx bundle size is limited by the max tx bundle size */
2628        target->max_rx_bndl_sz = target->max_xfer_szper_scatreq;
2629        /* Max tx bundle size if limited by the extended mbox address range */
2630        target->max_tx_bndl_sz = min(HIF_MBOX0_EXT_WIDTH,
2631                                     target->max_xfer_szper_scatreq);
2632
2633        ath6kl_dbg(ATH6KL_DBG_BOOT, "htc max_rx_bndl_sz %d max_tx_bndl_sz %d\n",
2634                   target->max_rx_bndl_sz, target->max_tx_bndl_sz);
2635
2636        if (target->max_tx_bndl_sz)
2637                /* tx_bndl_mask is enabled per AC, each has 1 bit */
2638                target->tx_bndl_mask = (1 << WMM_NUM_AC) - 1;
2639
2640        if (target->max_rx_bndl_sz)
2641                target->rx_bndl_enable = true;
2642
2643        if ((target->tgt_cred_sz % target->block_sz) != 0) {
2644                ath6kl_warn("credit size: %d is not block aligned! Disabling send bundling\n",
2645                            target->tgt_cred_sz);
2646
2647                /*
2648                 * Disallow send bundling since the credit size is
2649                 * not aligned to a block size the I/O block
2650                 * padding will spill into the next credit buffer
2651                 * which is fatal.
2652                 */
2653                target->tx_bndl_mask = 0;
2654        }
2655}
2656
2657static int ath6kl_htc_mbox_wait_target(struct htc_target *target)
2658{
2659        struct htc_packet *packet = NULL;
2660        struct htc_ready_ext_msg *rdy_msg;
2661        struct htc_service_connect_req connect;
2662        struct htc_service_connect_resp resp;
2663        int status;
2664
2665        /* we should be getting 1 control message that the target is ready */
2666        packet = htc_wait_for_ctrl_msg(target);
2667
2668        if (!packet)
2669                return -ENOMEM;
2670
2671        /* we controlled the buffer creation so it's properly aligned */
2672        rdy_msg = (struct htc_ready_ext_msg *)packet->buf;
2673
2674        if ((le16_to_cpu(rdy_msg->ver2_0_info.msg_id) != HTC_MSG_READY_ID) ||
2675            (packet->act_len < sizeof(struct htc_ready_msg))) {
2676                status = -ENOMEM;
2677                goto fail_wait_target;
2678        }
2679
2680        if (!rdy_msg->ver2_0_info.cred_cnt || !rdy_msg->ver2_0_info.cred_sz) {
2681                status = -ENOMEM;
2682                goto fail_wait_target;
2683        }
2684
2685        target->tgt_creds = le16_to_cpu(rdy_msg->ver2_0_info.cred_cnt);
2686        target->tgt_cred_sz = le16_to_cpu(rdy_msg->ver2_0_info.cred_sz);
2687
2688        ath6kl_dbg(ATH6KL_DBG_BOOT,
2689                   "htc target ready credits %d size %d\n",
2690                   target->tgt_creds, target->tgt_cred_sz);
2691
2692        /* check if this is an extended ready message */
2693        if (packet->act_len >= sizeof(struct htc_ready_ext_msg)) {
2694                /* this is an extended message */
2695                target->htc_tgt_ver = rdy_msg->htc_ver;
2696                target->msg_per_bndl_max = rdy_msg->msg_per_htc_bndl;
2697        } else {
2698                /* legacy */
2699                target->htc_tgt_ver = HTC_VERSION_2P0;
2700                target->msg_per_bndl_max = 0;
2701        }
2702
2703        ath6kl_dbg(ATH6KL_DBG_BOOT, "htc using protocol %s (%d)\n",
2704                   (target->htc_tgt_ver == HTC_VERSION_2P0) ? "2.0" : ">= 2.1",
2705                   target->htc_tgt_ver);
2706
2707        if (target->msg_per_bndl_max > 0)
2708                htc_setup_msg_bndl(target);
2709
2710        /* setup our pseudo HTC control endpoint connection */
2711        memset(&connect, 0, sizeof(connect));
2712        memset(&resp, 0, sizeof(resp));
2713        connect.ep_cb.rx = htc_ctrl_rx;
2714        connect.ep_cb.rx_refill = NULL;
2715        connect.ep_cb.tx_full = NULL;
2716        connect.max_txq_depth = NUM_CONTROL_BUFFERS;
2717        connect.svc_id = HTC_CTRL_RSVD_SVC;
2718
2719        /* connect fake service */
2720        status = ath6kl_htc_mbox_conn_service((void *)target, &connect, &resp);
2721
2722        if (status)
2723                /*
2724                 * FIXME: this call doesn't make sense, the caller should
2725                 * call ath6kl_htc_mbox_cleanup() when it wants remove htc
2726                 */
2727                ath6kl_hif_cleanup_scatter(target->dev->ar);
2728
2729fail_wait_target:
2730        if (packet) {
2731                htc_rxpkt_reset(packet);
2732                reclaim_rx_ctrl_buf(target, packet);
2733        }
2734
2735        return status;
2736}
2737
2738/*
2739 * Start HTC, enable interrupts and let the target know
2740 * host has finished setup.
2741 */
2742static int ath6kl_htc_mbox_start(struct htc_target *target)
2743{
2744        struct htc_packet *packet;
2745        int status;
2746
2747        memset(&target->dev->irq_proc_reg, 0,
2748               sizeof(target->dev->irq_proc_reg));
2749
2750        /* Disable interrupts at the chip level */
2751        ath6kl_hif_disable_intrs(target->dev);
2752
2753        target->htc_flags = 0;
2754        target->rx_st_flags = 0;
2755
2756        /* Push control receive buffers into htc control endpoint */
2757        while ((packet = htc_get_control_buf(target, false)) != NULL) {
2758                status = htc_add_rxbuf(target, packet);
2759                if (status)
2760                        return status;
2761        }
2762
2763        /* NOTE: the first entry in the distribution list is ENDPOINT_0 */
2764        ath6kl_credit_init(target->credit_info, &target->cred_dist_list,
2765                           target->tgt_creds);
2766
2767        dump_cred_dist_stats(target);
2768
2769        /* Indicate to the target of the setup completion */
2770        status = htc_setup_tx_complete(target);
2771
2772        if (status)
2773                return status;
2774
2775        /* unmask interrupts */
2776        status = ath6kl_hif_unmask_intrs(target->dev);
2777
2778        if (status)
2779                ath6kl_htc_mbox_stop(target);
2780
2781        return status;
2782}
2783
2784static int ath6kl_htc_reset(struct htc_target *target)
2785{
2786        u32 block_size, ctrl_bufsz;
2787        struct htc_packet *packet;
2788        int i;
2789
2790        reset_ep_state(target);
2791
2792        block_size = target->dev->ar->mbox_info.block_size;
2793
2794        ctrl_bufsz = (block_size > HTC_MAX_CTRL_MSG_LEN) ?
2795                      (block_size + HTC_HDR_LENGTH) :
2796                      (HTC_MAX_CTRL_MSG_LEN + HTC_HDR_LENGTH);
2797
2798        for (i = 0; i < NUM_CONTROL_BUFFERS; i++) {
2799                packet = kzalloc(sizeof(*packet), GFP_KERNEL);
2800                if (!packet)
2801                        return -ENOMEM;
2802
2803                packet->buf_start = kzalloc(ctrl_bufsz, GFP_KERNEL);
2804                if (!packet->buf_start) {
2805                        kfree(packet);
2806                        return -ENOMEM;
2807                }
2808
2809                packet->buf_len = ctrl_bufsz;
2810                if (i < NUM_CONTROL_RX_BUFFERS) {
2811                        packet->act_len = 0;
2812                        packet->buf = packet->buf_start;
2813                        packet->endpoint = ENDPOINT_0;
2814                        list_add_tail(&packet->list, &target->free_ctrl_rxbuf);
2815                } else {
2816                        list_add_tail(&packet->list, &target->free_ctrl_txbuf);
2817                }
2818        }
2819
2820        return 0;
2821}
2822
2823/* htc_stop: stop interrupt reception, and flush all queued buffers */
2824static void ath6kl_htc_mbox_stop(struct htc_target *target)
2825{
2826        spin_lock_bh(&target->htc_lock);
2827        target->htc_flags |= HTC_OP_STATE_STOPPING;
2828        spin_unlock_bh(&target->htc_lock);
2829
2830        /*
2831         * Masking interrupts is a synchronous operation, when this
2832         * function returns all pending HIF I/O has completed, we can
2833         * safely flush the queues.
2834         */
2835        ath6kl_hif_mask_intrs(target->dev);
2836
2837        ath6kl_htc_flush_txep_all(target);
2838
2839        ath6kl_htc_mbox_flush_rx_buf(target);
2840
2841        ath6kl_htc_reset(target);
2842}
2843
2844static void *ath6kl_htc_mbox_create(struct ath6kl *ar)
2845{
2846        struct htc_target *target = NULL;
2847        int status = 0;
2848
2849        target = kzalloc(sizeof(*target), GFP_KERNEL);
2850        if (!target) {
2851                ath6kl_err("unable to allocate memory\n");
2852                return NULL;
2853        }
2854
2855        target->dev = kzalloc(sizeof(*target->dev), GFP_KERNEL);
2856        if (!target->dev) {
2857                ath6kl_err("unable to allocate memory\n");
2858                kfree(target);
2859                return NULL;
2860        }
2861
2862        spin_lock_init(&target->htc_lock);
2863        spin_lock_init(&target->rx_lock);
2864        spin_lock_init(&target->tx_lock);
2865
2866        INIT_LIST_HEAD(&target->free_ctrl_txbuf);
2867        INIT_LIST_HEAD(&target->free_ctrl_rxbuf);
2868        INIT_LIST_HEAD(&target->cred_dist_list);
2869
2870        target->dev->ar = ar;
2871        target->dev->htc_cnxt = target;
2872        target->ep_waiting = ENDPOINT_MAX;
2873
2874        status = ath6kl_hif_setup(target->dev);
2875        if (status)
2876                goto err_htc_cleanup;
2877
2878        status = ath6kl_htc_reset(target);
2879        if (status)
2880                goto err_htc_cleanup;
2881
2882        return target;
2883
2884err_htc_cleanup:
2885        ath6kl_htc_mbox_cleanup(target);
2886
2887        return NULL;
2888}
2889
2890/* cleanup the HTC instance */
2891static void ath6kl_htc_mbox_cleanup(struct htc_target *target)
2892{
2893        struct htc_packet *packet, *tmp_packet;
2894
2895        ath6kl_hif_cleanup_scatter(target->dev->ar);
2896
2897        list_for_each_entry_safe(packet, tmp_packet,
2898                                 &target->free_ctrl_txbuf, list) {
2899                list_del(&packet->list);
2900                kfree(packet->buf_start);
2901                kfree(packet);
2902        }
2903
2904        list_for_each_entry_safe(packet, tmp_packet,
2905                                 &target->free_ctrl_rxbuf, list) {
2906                list_del(&packet->list);
2907                kfree(packet->buf_start);
2908                kfree(packet);
2909        }
2910
2911        kfree(target->dev);
2912        kfree(target);
2913}
2914
2915static const struct ath6kl_htc_ops ath6kl_htc_mbox_ops = {
2916        .create = ath6kl_htc_mbox_create,
2917        .wait_target = ath6kl_htc_mbox_wait_target,
2918        .start = ath6kl_htc_mbox_start,
2919        .conn_service = ath6kl_htc_mbox_conn_service,
2920        .tx = ath6kl_htc_mbox_tx,
2921        .stop = ath6kl_htc_mbox_stop,
2922        .cleanup = ath6kl_htc_mbox_cleanup,
2923        .flush_txep = ath6kl_htc_mbox_flush_txep,
2924        .flush_rx_buf = ath6kl_htc_mbox_flush_rx_buf,
2925        .activity_changed = ath6kl_htc_mbox_activity_changed,
2926        .get_rxbuf_num = ath6kl_htc_mbox_get_rxbuf_num,
2927        .add_rxbuf_multiple = ath6kl_htc_mbox_add_rxbuf_multiple,
2928        .credit_setup = ath6kl_htc_mbox_credit_setup,
2929};
2930
2931void ath6kl_htc_mbox_attach(struct ath6kl *ar)
2932{
2933        ar->htc_ops = &ath6kl_htc_mbox_ops;
2934}
2935