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v6.8
   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 unavailability 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_look_ahead look_ahead;
 
2264
2265	if (ath6kl_hif_poll_mboxmsg_rx(target->dev, &look_ahead.word,
2266				       HTC_TARGET_RESPONSE_TIMEOUT))
2267		return NULL;
2268
2269	ath6kl_dbg(ATH6KL_DBG_HTC,
2270		   "htc rx wait ctrl look_ahead 0x%X\n", look_ahead.word);
2271
2272	if (look_ahead.eid != ENDPOINT_0)
 
 
2273		return NULL;
2274
2275	packet = htc_get_control_buf(target, false);
2276
2277	if (!packet)
2278		return NULL;
2279
2280	packet->info.rx.rx_flags = 0;
2281	packet->info.rx.exp_hdr = look_ahead.word;
2282	packet->act_len = le16_to_cpu(look_ahead.payld_len) + HTC_HDR_LENGTH;
2283
2284	if (packet->act_len > packet->buf_len)
2285		goto fail_ctrl_rx;
2286
2287	/* we want synchronous operation */
2288	packet->completion = NULL;
2289
2290	/* get the message from the device, this will block */
2291	if (ath6kl_htc_rx_packet(target, packet, packet->act_len))
2292		goto fail_ctrl_rx;
2293
2294	trace_ath6kl_htc_rx(packet->status, packet->endpoint,
2295			    packet->buf, packet->act_len);
2296
2297	/* process receive header */
2298	packet->status = ath6kl_htc_rx_process_hdr(target, packet, NULL, NULL);
2299
2300	if (packet->status) {
2301		ath6kl_err("htc_wait_for_ctrl_msg, ath6kl_htc_rx_process_hdr failed (status = %d)\n",
2302			   packet->status);
2303		goto fail_ctrl_rx;
2304	}
2305
2306	return packet;
2307
2308fail_ctrl_rx:
2309	if (packet != NULL) {
2310		htc_rxpkt_reset(packet);
2311		reclaim_rx_ctrl_buf(target, packet);
2312	}
2313
2314	return NULL;
2315}
2316
2317static int ath6kl_htc_mbox_add_rxbuf_multiple(struct htc_target *target,
2318				  struct list_head *pkt_queue)
2319{
2320	struct htc_endpoint *endpoint;
2321	struct htc_packet *first_pkt;
2322	bool rx_unblock = false;
2323	int status = 0, depth;
2324
2325	if (list_empty(pkt_queue))
2326		return -ENOMEM;
2327
2328	first_pkt = list_first_entry(pkt_queue, struct htc_packet, list);
2329
2330	if (first_pkt->endpoint >= ENDPOINT_MAX)
2331		return status;
2332
2333	depth = get_queue_depth(pkt_queue);
2334
2335	ath6kl_dbg(ATH6KL_DBG_HTC,
2336		   "htc rx add multiple ep id %d cnt %d len %d\n",
2337		first_pkt->endpoint, depth, first_pkt->buf_len);
2338
2339	endpoint = &target->endpoint[first_pkt->endpoint];
2340
2341	if (target->htc_flags & HTC_OP_STATE_STOPPING) {
2342		struct htc_packet *packet, *tmp_pkt;
2343
2344		/* walk through queue and mark each one canceled */
2345		list_for_each_entry_safe(packet, tmp_pkt, pkt_queue, list) {
2346			packet->status = -ECANCELED;
2347			list_del(&packet->list);
2348			ath6kl_htc_rx_complete(endpoint, packet);
2349		}
2350
2351		return status;
2352	}
2353
2354	spin_lock_bh(&target->rx_lock);
2355
2356	list_splice_tail_init(pkt_queue, &endpoint->rx_bufq);
2357
2358	/* check if we are blocked waiting for a new buffer */
2359	if (target->rx_st_flags & HTC_RECV_WAIT_BUFFERS) {
2360		if (target->ep_waiting == first_pkt->endpoint) {
2361			ath6kl_dbg(ATH6KL_DBG_HTC,
2362				   "htc rx blocked on ep %d, unblocking\n",
2363				   target->ep_waiting);
2364			target->rx_st_flags &= ~HTC_RECV_WAIT_BUFFERS;
2365			target->ep_waiting = ENDPOINT_MAX;
2366			rx_unblock = true;
2367		}
2368	}
2369
2370	spin_unlock_bh(&target->rx_lock);
2371
2372	if (rx_unblock && !(target->htc_flags & HTC_OP_STATE_STOPPING))
2373		/* TODO : implement a buffer threshold count? */
2374		ath6kl_hif_rx_control(target->dev, true);
2375
2376	return status;
2377}
2378
2379static void ath6kl_htc_mbox_flush_rx_buf(struct htc_target *target)
2380{
2381	struct htc_endpoint *endpoint;
2382	struct htc_packet *packet, *tmp_pkt;
2383	int i;
2384
2385	for (i = ENDPOINT_0; i < ENDPOINT_MAX; i++) {
2386		endpoint = &target->endpoint[i];
2387		if (!endpoint->svc_id)
2388			/* not in use.. */
2389			continue;
2390
2391		spin_lock_bh(&target->rx_lock);
2392		list_for_each_entry_safe(packet, tmp_pkt,
2393					 &endpoint->rx_bufq, list) {
2394			list_del(&packet->list);
2395			spin_unlock_bh(&target->rx_lock);
2396			ath6kl_dbg(ATH6KL_DBG_HTC,
2397				   "htc rx flush pkt 0x%p  len %d  ep %d\n",
2398				   packet, packet->buf_len,
2399				   packet->endpoint);
2400			/*
2401			 * packets in rx_bufq of endpoint 0 have originally
2402			 * been queued from target->free_ctrl_rxbuf where
2403			 * packet and packet->buf_start are allocated
2404			 * separately using kmalloc(). For other endpoint
2405			 * rx_bufq, it is allocated as skb where packet is
2406			 * skb->head. Take care of this difference while freeing
2407			 * the memory.
2408			 */
2409			if (packet->endpoint == ENDPOINT_0) {
2410				kfree(packet->buf_start);
2411				kfree(packet);
2412			} else {
2413				dev_kfree_skb(packet->pkt_cntxt);
2414			}
2415			spin_lock_bh(&target->rx_lock);
2416		}
2417		spin_unlock_bh(&target->rx_lock);
2418	}
2419}
2420
2421static int ath6kl_htc_mbox_conn_service(struct htc_target *target,
2422			    struct htc_service_connect_req *conn_req,
2423			    struct htc_service_connect_resp *conn_resp)
2424{
2425	struct htc_packet *rx_pkt = NULL;
2426	struct htc_packet *tx_pkt = NULL;
2427	struct htc_conn_service_resp *resp_msg;
2428	struct htc_conn_service_msg *conn_msg;
2429	struct htc_endpoint *endpoint;
2430	enum htc_endpoint_id assigned_ep = ENDPOINT_MAX;
2431	unsigned int max_msg_sz = 0;
2432	int status = 0;
2433	u16 msg_id;
2434
2435	ath6kl_dbg(ATH6KL_DBG_HTC,
2436		   "htc connect service target 0x%p service id 0x%x\n",
2437		   target, conn_req->svc_id);
2438
2439	if (conn_req->svc_id == HTC_CTRL_RSVD_SVC) {
2440		/* special case for pseudo control service */
2441		assigned_ep = ENDPOINT_0;
2442		max_msg_sz = HTC_MAX_CTRL_MSG_LEN;
2443	} else {
2444		/* allocate a packet to send to the target */
2445		tx_pkt = htc_get_control_buf(target, true);
2446
2447		if (!tx_pkt)
2448			return -ENOMEM;
2449
2450		conn_msg = (struct htc_conn_service_msg *)tx_pkt->buf;
2451		memset(conn_msg, 0, sizeof(*conn_msg));
2452		conn_msg->msg_id = cpu_to_le16(HTC_MSG_CONN_SVC_ID);
2453		conn_msg->svc_id = cpu_to_le16(conn_req->svc_id);
2454		conn_msg->conn_flags = cpu_to_le16(conn_req->conn_flags);
2455
2456		set_htc_pkt_info(tx_pkt, NULL, (u8 *) conn_msg,
2457				 sizeof(*conn_msg) + conn_msg->svc_meta_len,
2458				 ENDPOINT_0, HTC_SERVICE_TX_PACKET_TAG);
2459
2460		/* we want synchronous operation */
2461		tx_pkt->completion = NULL;
2462		ath6kl_htc_tx_prep_pkt(tx_pkt, 0, 0, 0);
2463		status = ath6kl_htc_tx_issue(target, tx_pkt);
2464
2465		if (status)
2466			goto fail_tx;
2467
2468		/* wait for response */
2469		rx_pkt = htc_wait_for_ctrl_msg(target);
2470
2471		if (!rx_pkt) {
2472			status = -ENOMEM;
2473			goto fail_tx;
2474		}
2475
2476		resp_msg = (struct htc_conn_service_resp *)rx_pkt->buf;
2477		msg_id = le16_to_cpu(resp_msg->msg_id);
2478
2479		if ((msg_id != HTC_MSG_CONN_SVC_RESP_ID) ||
2480		    (rx_pkt->act_len < sizeof(*resp_msg))) {
2481			status = -ENOMEM;
2482			goto fail_tx;
2483		}
2484
2485		conn_resp->resp_code = resp_msg->status;
2486		/* check response status */
2487		if (resp_msg->status != HTC_SERVICE_SUCCESS) {
2488			ath6kl_err("target failed service 0x%X connect request (status:%d)\n",
2489				   resp_msg->svc_id, resp_msg->status);
2490			status = -ENOMEM;
2491			goto fail_tx;
2492		}
2493
2494		assigned_ep = (enum htc_endpoint_id)resp_msg->eid;
2495		max_msg_sz = le16_to_cpu(resp_msg->max_msg_sz);
2496	}
2497
2498	if (WARN_ON_ONCE(assigned_ep == ENDPOINT_UNUSED ||
2499			 assigned_ep >= ENDPOINT_MAX || !max_msg_sz)) {
2500		status = -ENOMEM;
2501		goto fail_tx;
2502	}
2503
2504	endpoint = &target->endpoint[assigned_ep];
2505	endpoint->eid = assigned_ep;
2506	if (endpoint->svc_id) {
2507		status = -ENOMEM;
2508		goto fail_tx;
2509	}
2510
2511	/* return assigned endpoint to caller */
2512	conn_resp->endpoint = assigned_ep;
2513	conn_resp->len_max = max_msg_sz;
2514
2515	/* setup the endpoint */
2516
2517	/* this marks the endpoint in use */
2518	endpoint->svc_id = conn_req->svc_id;
2519
2520	endpoint->max_txq_depth = conn_req->max_txq_depth;
2521	endpoint->len_max = max_msg_sz;
2522	endpoint->ep_cb = conn_req->ep_cb;
2523	endpoint->cred_dist.svc_id = conn_req->svc_id;
2524	endpoint->cred_dist.htc_ep = endpoint;
2525	endpoint->cred_dist.endpoint = assigned_ep;
2526	endpoint->cred_dist.cred_sz = target->tgt_cred_sz;
2527
2528	switch (endpoint->svc_id) {
2529	case WMI_DATA_BK_SVC:
2530		endpoint->tx_drop_packet_threshold = MAX_DEF_COOKIE_NUM / 3;
2531		break;
2532	default:
2533		endpoint->tx_drop_packet_threshold = MAX_HI_COOKIE_NUM;
2534		break;
2535	}
2536
2537	if (conn_req->max_rxmsg_sz) {
2538		/*
2539		 * Override cred_per_msg calculation, this optimizes
2540		 * the credit-low indications since the host will actually
2541		 * issue smaller messages in the Send path.
2542		 */
2543		if (conn_req->max_rxmsg_sz > max_msg_sz) {
2544			status = -ENOMEM;
2545			goto fail_tx;
2546		}
2547		endpoint->cred_dist.cred_per_msg =
2548		    conn_req->max_rxmsg_sz / target->tgt_cred_sz;
2549	} else
2550		endpoint->cred_dist.cred_per_msg =
2551		    max_msg_sz / target->tgt_cred_sz;
2552
2553	if (!endpoint->cred_dist.cred_per_msg)
2554		endpoint->cred_dist.cred_per_msg = 1;
2555
2556	/* save local connection flags */
2557	endpoint->conn_flags = conn_req->flags;
2558
2559fail_tx:
2560	if (tx_pkt)
2561		htc_reclaim_txctrl_buf(target, tx_pkt);
2562
2563	if (rx_pkt) {
2564		htc_rxpkt_reset(rx_pkt);
2565		reclaim_rx_ctrl_buf(target, rx_pkt);
2566	}
2567
2568	return status;
2569}
2570
2571static void reset_ep_state(struct htc_target *target)
2572{
2573	struct htc_endpoint *endpoint;
2574	int i;
2575
2576	for (i = ENDPOINT_0; i < ENDPOINT_MAX; i++) {
2577		endpoint = &target->endpoint[i];
2578		memset(&endpoint->cred_dist, 0, sizeof(endpoint->cred_dist));
2579		endpoint->svc_id = 0;
2580		endpoint->len_max = 0;
2581		endpoint->max_txq_depth = 0;
2582		memset(&endpoint->ep_st, 0,
2583		       sizeof(endpoint->ep_st));
2584		INIT_LIST_HEAD(&endpoint->rx_bufq);
2585		INIT_LIST_HEAD(&endpoint->txq);
2586		endpoint->target = target;
2587	}
2588
2589	/* reset distribution list */
2590	/* FIXME: free existing entries */
2591	INIT_LIST_HEAD(&target->cred_dist_list);
2592}
2593
2594static int ath6kl_htc_mbox_get_rxbuf_num(struct htc_target *target,
2595			     enum htc_endpoint_id endpoint)
2596{
2597	int num;
2598
2599	spin_lock_bh(&target->rx_lock);
2600	num = get_queue_depth(&(target->endpoint[endpoint].rx_bufq));
2601	spin_unlock_bh(&target->rx_lock);
2602	return num;
2603}
2604
2605static void htc_setup_msg_bndl(struct htc_target *target)
2606{
2607	/* limit what HTC can handle */
2608	target->msg_per_bndl_max = min(HTC_HOST_MAX_MSG_PER_BUNDLE,
2609				       target->msg_per_bndl_max);
2610
2611	if (ath6kl_hif_enable_scatter(target->dev->ar)) {
2612		target->msg_per_bndl_max = 0;
2613		return;
2614	}
2615
2616	/* limit bundle what the device layer can handle */
2617	target->msg_per_bndl_max = min(target->max_scat_entries,
2618				       target->msg_per_bndl_max);
2619
2620	ath6kl_dbg(ATH6KL_DBG_BOOT,
2621		   "htc bundling allowed msg_per_bndl_max %d\n",
2622		   target->msg_per_bndl_max);
2623
2624	/* Max rx bundle size is limited by the max tx bundle size */
2625	target->max_rx_bndl_sz = target->max_xfer_szper_scatreq;
2626	/* Max tx bundle size if limited by the extended mbox address range */
2627	target->max_tx_bndl_sz = min(HIF_MBOX0_EXT_WIDTH,
2628				     target->max_xfer_szper_scatreq);
2629
2630	ath6kl_dbg(ATH6KL_DBG_BOOT, "htc max_rx_bndl_sz %d max_tx_bndl_sz %d\n",
2631		   target->max_rx_bndl_sz, target->max_tx_bndl_sz);
2632
2633	if (target->max_tx_bndl_sz)
2634		/* tx_bndl_mask is enabled per AC, each has 1 bit */
2635		target->tx_bndl_mask = (1 << WMM_NUM_AC) - 1;
2636
2637	if (target->max_rx_bndl_sz)
2638		target->rx_bndl_enable = true;
2639
2640	if ((target->tgt_cred_sz % target->block_sz) != 0) {
2641		ath6kl_warn("credit size: %d is not block aligned! Disabling send bundling\n",
2642			    target->tgt_cred_sz);
2643
2644		/*
2645		 * Disallow send bundling since the credit size is
2646		 * not aligned to a block size the I/O block
2647		 * padding will spill into the next credit buffer
2648		 * which is fatal.
2649		 */
2650		target->tx_bndl_mask = 0;
2651	}
2652}
2653
2654static int ath6kl_htc_mbox_wait_target(struct htc_target *target)
2655{
2656	struct htc_packet *packet = NULL;
2657	struct htc_ready_ext_msg *rdy_msg;
2658	struct htc_service_connect_req connect;
2659	struct htc_service_connect_resp resp;
2660	int status;
2661
2662	/* we should be getting 1 control message that the target is ready */
2663	packet = htc_wait_for_ctrl_msg(target);
2664
2665	if (!packet)
2666		return -ENOMEM;
2667
2668	/* we controlled the buffer creation so it's properly aligned */
2669	rdy_msg = (struct htc_ready_ext_msg *)packet->buf;
2670
2671	if ((le16_to_cpu(rdy_msg->ver2_0_info.msg_id) != HTC_MSG_READY_ID) ||
2672	    (packet->act_len < sizeof(struct htc_ready_msg))) {
2673		status = -ENOMEM;
2674		goto fail_wait_target;
2675	}
2676
2677	if (!rdy_msg->ver2_0_info.cred_cnt || !rdy_msg->ver2_0_info.cred_sz) {
2678		status = -ENOMEM;
2679		goto fail_wait_target;
2680	}
2681
2682	target->tgt_creds = le16_to_cpu(rdy_msg->ver2_0_info.cred_cnt);
2683	target->tgt_cred_sz = le16_to_cpu(rdy_msg->ver2_0_info.cred_sz);
2684
2685	ath6kl_dbg(ATH6KL_DBG_BOOT,
2686		   "htc target ready credits %d size %d\n",
2687		   target->tgt_creds, target->tgt_cred_sz);
2688
2689	/* check if this is an extended ready message */
2690	if (packet->act_len >= sizeof(struct htc_ready_ext_msg)) {
2691		/* this is an extended message */
2692		target->htc_tgt_ver = rdy_msg->htc_ver;
2693		target->msg_per_bndl_max = rdy_msg->msg_per_htc_bndl;
2694	} else {
2695		/* legacy */
2696		target->htc_tgt_ver = HTC_VERSION_2P0;
2697		target->msg_per_bndl_max = 0;
2698	}
2699
2700	ath6kl_dbg(ATH6KL_DBG_BOOT, "htc using protocol %s (%d)\n",
2701		   (target->htc_tgt_ver == HTC_VERSION_2P0) ? "2.0" : ">= 2.1",
2702		   target->htc_tgt_ver);
2703
2704	if (target->msg_per_bndl_max > 0)
2705		htc_setup_msg_bndl(target);
2706
2707	/* setup our pseudo HTC control endpoint connection */
2708	memset(&connect, 0, sizeof(connect));
2709	memset(&resp, 0, sizeof(resp));
2710	connect.ep_cb.rx = htc_ctrl_rx;
2711	connect.ep_cb.rx_refill = NULL;
2712	connect.ep_cb.tx_full = NULL;
2713	connect.max_txq_depth = NUM_CONTROL_BUFFERS;
2714	connect.svc_id = HTC_CTRL_RSVD_SVC;
2715
2716	/* connect fake service */
2717	status = ath6kl_htc_mbox_conn_service((void *)target, &connect, &resp);
2718
2719	if (status)
2720		/*
2721		 * FIXME: this call doesn't make sense, the caller should
2722		 * call ath6kl_htc_mbox_cleanup() when it wants remove htc
2723		 */
2724		ath6kl_hif_cleanup_scatter(target->dev->ar);
2725
2726fail_wait_target:
2727	if (packet) {
2728		htc_rxpkt_reset(packet);
2729		reclaim_rx_ctrl_buf(target, packet);
2730	}
2731
2732	return status;
2733}
2734
2735/*
2736 * Start HTC, enable interrupts and let the target know
2737 * host has finished setup.
2738 */
2739static int ath6kl_htc_mbox_start(struct htc_target *target)
2740{
2741	struct htc_packet *packet;
2742	int status;
2743
2744	memset(&target->dev->irq_proc_reg, 0,
2745	       sizeof(target->dev->irq_proc_reg));
2746
2747	/* Disable interrupts at the chip level */
2748	ath6kl_hif_disable_intrs(target->dev);
2749
2750	target->htc_flags = 0;
2751	target->rx_st_flags = 0;
2752
2753	/* Push control receive buffers into htc control endpoint */
2754	while ((packet = htc_get_control_buf(target, false)) != NULL) {
2755		status = htc_add_rxbuf(target, packet);
2756		if (status)
2757			return status;
2758	}
2759
2760	/* NOTE: the first entry in the distribution list is ENDPOINT_0 */
2761	ath6kl_credit_init(target->credit_info, &target->cred_dist_list,
2762			   target->tgt_creds);
2763
2764	dump_cred_dist_stats(target);
2765
2766	/* Indicate to the target of the setup completion */
2767	status = htc_setup_tx_complete(target);
2768
2769	if (status)
2770		return status;
2771
2772	/* unmask interrupts */
2773	status = ath6kl_hif_unmask_intrs(target->dev);
2774
2775	if (status)
2776		ath6kl_htc_mbox_stop(target);
2777
2778	return status;
2779}
2780
2781static int ath6kl_htc_reset(struct htc_target *target)
2782{
2783	u32 block_size, ctrl_bufsz;
2784	struct htc_packet *packet;
2785	int i;
2786
2787	reset_ep_state(target);
2788
2789	block_size = target->dev->ar->mbox_info.block_size;
2790
2791	ctrl_bufsz = (block_size > HTC_MAX_CTRL_MSG_LEN) ?
2792		      (block_size + HTC_HDR_LENGTH) :
2793		      (HTC_MAX_CTRL_MSG_LEN + HTC_HDR_LENGTH);
2794
2795	for (i = 0; i < NUM_CONTROL_BUFFERS; i++) {
2796		packet = kzalloc(sizeof(*packet), GFP_KERNEL);
2797		if (!packet)
2798			return -ENOMEM;
2799
2800		packet->buf_start = kzalloc(ctrl_bufsz, GFP_KERNEL);
2801		if (!packet->buf_start) {
2802			kfree(packet);
2803			return -ENOMEM;
2804		}
2805
2806		packet->buf_len = ctrl_bufsz;
2807		if (i < NUM_CONTROL_RX_BUFFERS) {
2808			packet->act_len = 0;
2809			packet->buf = packet->buf_start;
2810			packet->endpoint = ENDPOINT_0;
2811			list_add_tail(&packet->list, &target->free_ctrl_rxbuf);
2812		} else {
2813			list_add_tail(&packet->list, &target->free_ctrl_txbuf);
2814		}
2815	}
2816
2817	return 0;
2818}
2819
2820/* htc_stop: stop interrupt reception, and flush all queued buffers */
2821static void ath6kl_htc_mbox_stop(struct htc_target *target)
2822{
2823	spin_lock_bh(&target->htc_lock);
2824	target->htc_flags |= HTC_OP_STATE_STOPPING;
2825	spin_unlock_bh(&target->htc_lock);
2826
2827	/*
2828	 * Masking interrupts is a synchronous operation, when this
2829	 * function returns all pending HIF I/O has completed, we can
2830	 * safely flush the queues.
2831	 */
2832	ath6kl_hif_mask_intrs(target->dev);
2833
2834	ath6kl_htc_flush_txep_all(target);
2835
2836	ath6kl_htc_mbox_flush_rx_buf(target);
2837
2838	ath6kl_htc_reset(target);
2839}
2840
2841static void *ath6kl_htc_mbox_create(struct ath6kl *ar)
2842{
2843	struct htc_target *target = NULL;
2844	int status = 0;
2845
2846	target = kzalloc(sizeof(*target), GFP_KERNEL);
2847	if (!target) {
2848		ath6kl_err("unable to allocate memory\n");
2849		return NULL;
2850	}
2851
2852	target->dev = kzalloc(sizeof(*target->dev), GFP_KERNEL);
2853	if (!target->dev) {
2854		ath6kl_err("unable to allocate memory\n");
2855		kfree(target);
2856		return NULL;
2857	}
2858
2859	spin_lock_init(&target->htc_lock);
2860	spin_lock_init(&target->rx_lock);
2861	spin_lock_init(&target->tx_lock);
2862
2863	INIT_LIST_HEAD(&target->free_ctrl_txbuf);
2864	INIT_LIST_HEAD(&target->free_ctrl_rxbuf);
2865	INIT_LIST_HEAD(&target->cred_dist_list);
2866
2867	target->dev->ar = ar;
2868	target->dev->htc_cnxt = target;
2869	target->ep_waiting = ENDPOINT_MAX;
2870
2871	status = ath6kl_hif_setup(target->dev);
2872	if (status)
2873		goto err_htc_cleanup;
2874
2875	status = ath6kl_htc_reset(target);
2876	if (status)
2877		goto err_htc_cleanup;
2878
2879	return target;
2880
2881err_htc_cleanup:
2882	ath6kl_htc_mbox_cleanup(target);
2883
2884	return NULL;
2885}
2886
2887/* cleanup the HTC instance */
2888static void ath6kl_htc_mbox_cleanup(struct htc_target *target)
2889{
2890	struct htc_packet *packet, *tmp_packet;
2891
2892	ath6kl_hif_cleanup_scatter(target->dev->ar);
2893
2894	list_for_each_entry_safe(packet, tmp_packet,
2895				 &target->free_ctrl_txbuf, list) {
2896		list_del(&packet->list);
2897		kfree(packet->buf_start);
2898		kfree(packet);
2899	}
2900
2901	list_for_each_entry_safe(packet, tmp_packet,
2902				 &target->free_ctrl_rxbuf, list) {
2903		list_del(&packet->list);
2904		kfree(packet->buf_start);
2905		kfree(packet);
2906	}
2907
2908	kfree(target->dev);
2909	kfree(target);
2910}
2911
2912static const struct ath6kl_htc_ops ath6kl_htc_mbox_ops = {
2913	.create = ath6kl_htc_mbox_create,
2914	.wait_target = ath6kl_htc_mbox_wait_target,
2915	.start = ath6kl_htc_mbox_start,
2916	.conn_service = ath6kl_htc_mbox_conn_service,
2917	.tx = ath6kl_htc_mbox_tx,
2918	.stop = ath6kl_htc_mbox_stop,
2919	.cleanup = ath6kl_htc_mbox_cleanup,
2920	.flush_txep = ath6kl_htc_mbox_flush_txep,
2921	.flush_rx_buf = ath6kl_htc_mbox_flush_rx_buf,
2922	.activity_changed = ath6kl_htc_mbox_activity_changed,
2923	.get_rxbuf_num = ath6kl_htc_mbox_get_rxbuf_num,
2924	.add_rxbuf_multiple = ath6kl_htc_mbox_add_rxbuf_multiple,
2925	.credit_setup = ath6kl_htc_mbox_credit_setup,
2926};
2927
2928void ath6kl_htc_mbox_attach(struct ath6kl *ar)
2929{
2930	ar->htc_ops = &ath6kl_htc_mbox_ops;
2931}
v3.15
   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
 135		ath6kl_dbg(ATH6KL_DBG_CREDIT,
 136			   "credit ep %d svc_id %d credits %d per_msg %d norm %d min %d\n",
 137			   cur_ep_dist->endpoint,
 138			   cur_ep_dist->svc_id,
 139			   cur_ep_dist->credits,
 140			   cur_ep_dist->cred_per_msg,
 141			   cur_ep_dist->cred_norm,
 142			   cur_ep_dist->cred_min);
 143	}
 144}
 145
 146/* initialize and setup credit distribution */
 147static int ath6kl_htc_mbox_credit_setup(struct htc_target *htc_target,
 148			       struct ath6kl_htc_credit_info *cred_info)
 149{
 150	u16 servicepriority[5];
 151
 152	memset(cred_info, 0, sizeof(struct ath6kl_htc_credit_info));
 153
 154	servicepriority[0] = WMI_CONTROL_SVC;  /* highest */
 155	servicepriority[1] = WMI_DATA_VO_SVC;
 156	servicepriority[2] = WMI_DATA_VI_SVC;
 157	servicepriority[3] = WMI_DATA_BE_SVC;
 158	servicepriority[4] = WMI_DATA_BK_SVC; /* lowest */
 159
 160	/* set priority list */
 161	ath6kl_htc_set_credit_dist(htc_target, cred_info, servicepriority, 5);
 162
 163	return 0;
 164}
 165
 166/* reduce an ep's credits back to a set limit */
 167static void ath6kl_credit_reduce(struct ath6kl_htc_credit_info *cred_info,
 168				 struct htc_endpoint_credit_dist *ep_dist,
 169				 int limit)
 170{
 171	int credits;
 172
 173	ath6kl_dbg(ATH6KL_DBG_CREDIT, "credit reduce ep %d limit %d\n",
 174		   ep_dist->endpoint, limit);
 175
 176	ep_dist->cred_assngd = limit;
 177
 178	if (ep_dist->credits <= limit)
 179		return;
 180
 181	credits = ep_dist->credits - limit;
 182	ep_dist->credits -= credits;
 183	cred_info->cur_free_credits += credits;
 184}
 185
 186static void ath6kl_credit_update(struct ath6kl_htc_credit_info *cred_info,
 187				 struct list_head *epdist_list)
 188{
 189	struct htc_endpoint_credit_dist *cur_list;
 190
 191	list_for_each_entry(cur_list, epdist_list, list) {
 192		if (cur_list->endpoint == ENDPOINT_0)
 193			continue;
 194
 195		if (cur_list->cred_to_dist > 0) {
 196			cur_list->credits += cur_list->cred_to_dist;
 197			cur_list->cred_to_dist = 0;
 198
 199			if (cur_list->credits > cur_list->cred_assngd)
 200				ath6kl_credit_reduce(cred_info,
 201						     cur_list,
 202						     cur_list->cred_assngd);
 203
 204			if (cur_list->credits > cur_list->cred_norm)
 205				ath6kl_credit_reduce(cred_info, cur_list,
 206						     cur_list->cred_norm);
 207
 208			if (!(cur_list->dist_flags & HTC_EP_ACTIVE)) {
 209				if (cur_list->txq_depth == 0)
 210					ath6kl_credit_reduce(cred_info,
 211							     cur_list, 0);
 212			}
 213		}
 214	}
 215}
 216
 217/*
 218 * HTC has an endpoint that needs credits, ep_dist is the endpoint in
 219 * question.
 220 */
 221static void ath6kl_credit_seek(struct ath6kl_htc_credit_info *cred_info,
 222				struct htc_endpoint_credit_dist *ep_dist)
 223{
 224	struct htc_endpoint_credit_dist *curdist_list;
 225	int credits = 0;
 226	int need;
 227
 228	if (ep_dist->svc_id == WMI_CONTROL_SVC)
 229		goto out;
 230
 231	if ((ep_dist->svc_id == WMI_DATA_VI_SVC) ||
 232	    (ep_dist->svc_id == WMI_DATA_VO_SVC))
 233		if ((ep_dist->cred_assngd >= ep_dist->cred_norm))
 234			goto out;
 235
 236	/*
 237	 * For all other services, we follow a simple algorithm of:
 238	 *
 239	 * 1. checking the free pool for credits
 240	 * 2. checking lower priority endpoints for credits to take
 241	 */
 242
 243	credits = min(cred_info->cur_free_credits, ep_dist->seek_cred);
 244
 245	if (credits >= ep_dist->seek_cred)
 246		goto out;
 247
 248	/*
 249	 * We don't have enough in the free pool, try taking away from
 250	 * lower priority services The rule for taking away credits:
 251	 *
 252	 *   1. Only take from lower priority endpoints
 253	 *   2. Only take what is allocated above the minimum (never
 254	 *      starve an endpoint completely)
 255	 *   3. Only take what you need.
 256	 */
 257
 258	list_for_each_entry_reverse(curdist_list,
 259				    &cred_info->lowestpri_ep_dist,
 260				    list) {
 261		if (curdist_list == ep_dist)
 262			break;
 263
 264		need = ep_dist->seek_cred - cred_info->cur_free_credits;
 265
 266		if ((curdist_list->cred_assngd - need) >=
 267		     curdist_list->cred_min) {
 268			/*
 269			 * The current one has been allocated more than
 270			 * it's minimum and it has enough credits assigned
 271			 * above it's minimum to fulfill our need try to
 272			 * take away just enough to fulfill our need.
 273			 */
 274			ath6kl_credit_reduce(cred_info, curdist_list,
 275					     curdist_list->cred_assngd - need);
 276
 277			if (cred_info->cur_free_credits >=
 278			    ep_dist->seek_cred)
 279				break;
 280		}
 281
 282		if (curdist_list->endpoint == ENDPOINT_0)
 283			break;
 284	}
 285
 286	credits = min(cred_info->cur_free_credits, ep_dist->seek_cred);
 287
 288out:
 289	/* did we find some credits? */
 290	if (credits)
 291		ath6kl_credit_deposit(cred_info, ep_dist, credits);
 292
 293	ep_dist->seek_cred = 0;
 294}
 295
 296/* redistribute credits based on activity change */
 297static void ath6kl_credit_redistribute(struct ath6kl_htc_credit_info *info,
 298				       struct list_head *ep_dist_list)
 299{
 300	struct htc_endpoint_credit_dist *curdist_list;
 301
 302	list_for_each_entry(curdist_list, ep_dist_list, list) {
 303		if (curdist_list->endpoint == ENDPOINT_0)
 304			continue;
 305
 306		if ((curdist_list->svc_id == WMI_DATA_BK_SVC)  ||
 307		    (curdist_list->svc_id == WMI_DATA_BE_SVC))
 308			curdist_list->dist_flags |= HTC_EP_ACTIVE;
 309
 310		if ((curdist_list->svc_id != WMI_CONTROL_SVC) &&
 311		    !(curdist_list->dist_flags & HTC_EP_ACTIVE)) {
 312			if (curdist_list->txq_depth == 0)
 313				ath6kl_credit_reduce(info, curdist_list, 0);
 314			else
 315				ath6kl_credit_reduce(info,
 316						     curdist_list,
 317						     curdist_list->cred_min);
 318		}
 319	}
 320}
 321
 322/*
 323 *
 324 * This function is invoked whenever endpoints require credit
 325 * distributions. A lock is held while this function is invoked, this
 326 * function shall NOT block. The ep_dist_list is a list of distribution
 327 * structures in prioritized order as defined by the call to the
 328 * htc_set_credit_dist() api.
 329 */
 330static void ath6kl_credit_distribute(struct ath6kl_htc_credit_info *cred_info,
 331				     struct list_head *ep_dist_list,
 332			      enum htc_credit_dist_reason reason)
 333{
 334	switch (reason) {
 335	case HTC_CREDIT_DIST_SEND_COMPLETE:
 336		ath6kl_credit_update(cred_info, ep_dist_list);
 337		break;
 338	case HTC_CREDIT_DIST_ACTIVITY_CHANGE:
 339		ath6kl_credit_redistribute(cred_info, ep_dist_list);
 340		break;
 341	default:
 342		break;
 343	}
 344
 345	WARN_ON(cred_info->cur_free_credits > cred_info->total_avail_credits);
 346	WARN_ON(cred_info->cur_free_credits < 0);
 347}
 348
 349static void ath6kl_htc_tx_buf_align(u8 **buf, unsigned long len)
 350{
 351	u8 *align_addr;
 352
 353	if (!IS_ALIGNED((unsigned long) *buf, 4)) {
 354		align_addr = PTR_ALIGN(*buf - 4, 4);
 355		memmove(align_addr, *buf, len);
 356		*buf = align_addr;
 357	}
 358}
 359
 360static void ath6kl_htc_tx_prep_pkt(struct htc_packet *packet, u8 flags,
 361				   int ctrl0, int ctrl1)
 362{
 363	struct htc_frame_hdr *hdr;
 364
 365	packet->buf -= HTC_HDR_LENGTH;
 366	hdr =  (struct htc_frame_hdr *)packet->buf;
 367
 368	/* Endianess? */
 369	put_unaligned((u16)packet->act_len, &hdr->payld_len);
 370	hdr->flags = flags;
 371	hdr->eid = packet->endpoint;
 372	hdr->ctrl[0] = ctrl0;
 373	hdr->ctrl[1] = ctrl1;
 374}
 375
 376static void htc_reclaim_txctrl_buf(struct htc_target *target,
 377				   struct htc_packet *pkt)
 378{
 379	spin_lock_bh(&target->htc_lock);
 380	list_add_tail(&pkt->list, &target->free_ctrl_txbuf);
 381	spin_unlock_bh(&target->htc_lock);
 382}
 383
 384static struct htc_packet *htc_get_control_buf(struct htc_target *target,
 385					      bool tx)
 386{
 387	struct htc_packet *packet = NULL;
 388	struct list_head *buf_list;
 389
 390	buf_list = tx ? &target->free_ctrl_txbuf : &target->free_ctrl_rxbuf;
 391
 392	spin_lock_bh(&target->htc_lock);
 393
 394	if (list_empty(buf_list)) {
 395		spin_unlock_bh(&target->htc_lock);
 396		return NULL;
 397	}
 398
 399	packet = list_first_entry(buf_list, struct htc_packet, list);
 400	list_del(&packet->list);
 401	spin_unlock_bh(&target->htc_lock);
 402
 403	if (tx)
 404		packet->buf = packet->buf_start + HTC_HDR_LENGTH;
 405
 406	return packet;
 407}
 408
 409static void htc_tx_comp_update(struct htc_target *target,
 410			       struct htc_endpoint *endpoint,
 411			       struct htc_packet *packet)
 412{
 413	packet->completion = NULL;
 414	packet->buf += HTC_HDR_LENGTH;
 415
 416	if (!packet->status)
 417		return;
 418
 419	ath6kl_err("req failed (status:%d, ep:%d, len:%d creds:%d)\n",
 420		   packet->status, packet->endpoint, packet->act_len,
 421		   packet->info.tx.cred_used);
 422
 423	/* on failure to submit, reclaim credits for this packet */
 424	spin_lock_bh(&target->tx_lock);
 425	endpoint->cred_dist.cred_to_dist +=
 426				packet->info.tx.cred_used;
 427	endpoint->cred_dist.txq_depth = get_queue_depth(&endpoint->txq);
 428
 429	ath6kl_dbg(ATH6KL_DBG_HTC, "htc tx ctxt 0x%p dist 0x%p\n",
 430		   target->credit_info, &target->cred_dist_list);
 431
 432	ath6kl_credit_distribute(target->credit_info,
 433				 &target->cred_dist_list,
 434				 HTC_CREDIT_DIST_SEND_COMPLETE);
 435
 436	spin_unlock_bh(&target->tx_lock);
 437}
 438
 439static void htc_tx_complete(struct htc_endpoint *endpoint,
 440			    struct list_head *txq)
 441{
 442	if (list_empty(txq))
 443		return;
 444
 445	ath6kl_dbg(ATH6KL_DBG_HTC,
 446		   "htc tx complete ep %d pkts %d\n",
 447		   endpoint->eid, get_queue_depth(txq));
 448
 449	ath6kl_tx_complete(endpoint->target, txq);
 450}
 451
 452static void htc_tx_comp_handler(struct htc_target *target,
 453				struct htc_packet *packet)
 454{
 455	struct htc_endpoint *endpoint = &target->endpoint[packet->endpoint];
 456	struct list_head container;
 457
 458	ath6kl_dbg(ATH6KL_DBG_HTC, "htc tx complete seqno %d\n",
 459		   packet->info.tx.seqno);
 460
 461	htc_tx_comp_update(target, endpoint, packet);
 462	INIT_LIST_HEAD(&container);
 463	list_add_tail(&packet->list, &container);
 464	/* do completion */
 465	htc_tx_complete(endpoint, &container);
 466}
 467
 468static void htc_async_tx_scat_complete(struct htc_target *target,
 469				       struct hif_scatter_req *scat_req)
 470{
 471	struct htc_endpoint *endpoint;
 472	struct htc_packet *packet;
 473	struct list_head tx_compq;
 474	int i;
 475
 476	INIT_LIST_HEAD(&tx_compq);
 477
 478	ath6kl_dbg(ATH6KL_DBG_HTC,
 479		   "htc tx scat complete len %d entries %d\n",
 480		   scat_req->len, scat_req->scat_entries);
 481
 482	if (scat_req->status)
 483		ath6kl_err("send scatter req failed: %d\n", scat_req->status);
 484
 485	packet = scat_req->scat_list[0].packet;
 486	endpoint = &target->endpoint[packet->endpoint];
 487
 488	/* walk through the scatter list and process */
 489	for (i = 0; i < scat_req->scat_entries; i++) {
 490		packet = scat_req->scat_list[i].packet;
 491		if (!packet) {
 492			WARN_ON(1);
 493			return;
 494		}
 495
 496		packet->status = scat_req->status;
 497		htc_tx_comp_update(target, endpoint, packet);
 498		list_add_tail(&packet->list, &tx_compq);
 499	}
 500
 501	/* free scatter request */
 502	hif_scatter_req_add(target->dev->ar, scat_req);
 503
 504	/* complete all packets */
 505	htc_tx_complete(endpoint, &tx_compq);
 506}
 507
 508static int ath6kl_htc_tx_issue(struct htc_target *target,
 509			       struct htc_packet *packet)
 510{
 511	int status;
 512	bool sync = false;
 513	u32 padded_len, send_len;
 514
 515	if (!packet->completion)
 516		sync = true;
 517
 518	send_len = packet->act_len + HTC_HDR_LENGTH;
 519
 520	padded_len = CALC_TXRX_PADDED_LEN(target, send_len);
 521
 522	ath6kl_dbg(ATH6KL_DBG_HTC,
 523		   "htc tx issue len %d seqno %d padded_len %d mbox 0x%X %s\n",
 524		   send_len, packet->info.tx.seqno, padded_len,
 525		   target->dev->ar->mbox_info.htc_addr,
 526		   sync ? "sync" : "async");
 527
 528	if (sync) {
 529		status = hif_read_write_sync(target->dev->ar,
 530				target->dev->ar->mbox_info.htc_addr,
 531				 packet->buf, padded_len,
 532				 HIF_WR_SYNC_BLOCK_INC);
 533
 534		packet->status = status;
 535		packet->buf += HTC_HDR_LENGTH;
 536	} else
 537		status = hif_write_async(target->dev->ar,
 538				target->dev->ar->mbox_info.htc_addr,
 539				packet->buf, padded_len,
 540				HIF_WR_ASYNC_BLOCK_INC, packet);
 541
 542	trace_ath6kl_htc_tx(status, packet->endpoint, packet->buf, send_len);
 543
 544	return status;
 545}
 546
 547static int htc_check_credits(struct htc_target *target,
 548			     struct htc_endpoint *ep, u8 *flags,
 549			     enum htc_endpoint_id eid, unsigned int len,
 550			     int *req_cred)
 551{
 552
 553	*req_cred = (len > target->tgt_cred_sz) ?
 554		     DIV_ROUND_UP(len, target->tgt_cred_sz) : 1;
 555
 556	ath6kl_dbg(ATH6KL_DBG_CREDIT, "credit check need %d got %d\n",
 557		   *req_cred, ep->cred_dist.credits);
 558
 559	if (ep->cred_dist.credits < *req_cred) {
 560		if (eid == ENDPOINT_0)
 561			return -EINVAL;
 562
 563		/* Seek more credits */
 564		ep->cred_dist.seek_cred = *req_cred - ep->cred_dist.credits;
 565
 566		ath6kl_credit_seek(target->credit_info, &ep->cred_dist);
 567
 568		ep->cred_dist.seek_cred = 0;
 569
 570		if (ep->cred_dist.credits < *req_cred) {
 571			ath6kl_dbg(ATH6KL_DBG_CREDIT,
 572				   "credit not found for ep %d\n",
 573				   eid);
 574			return -EINVAL;
 575		}
 576	}
 577
 578	ep->cred_dist.credits -= *req_cred;
 579	ep->ep_st.cred_cosumd += *req_cred;
 580
 581	 /* When we are getting low on credits, ask for more */
 582	if (ep->cred_dist.credits < ep->cred_dist.cred_per_msg) {
 583		ep->cred_dist.seek_cred =
 584		ep->cred_dist.cred_per_msg - ep->cred_dist.credits;
 585
 586		ath6kl_credit_seek(target->credit_info, &ep->cred_dist);
 587
 588		/* see if we were successful in getting more */
 589		if (ep->cred_dist.credits < ep->cred_dist.cred_per_msg) {
 590			/* tell the target we need credits ASAP! */
 591			*flags |= HTC_FLAGS_NEED_CREDIT_UPDATE;
 592			ep->ep_st.cred_low_indicate += 1;
 593			ath6kl_dbg(ATH6KL_DBG_CREDIT,
 594				   "credit we need credits asap\n");
 595		}
 596	}
 597
 598	return 0;
 599}
 600
 601static void ath6kl_htc_tx_pkts_get(struct htc_target *target,
 602				   struct htc_endpoint *endpoint,
 603				   struct list_head *queue)
 604{
 605	int req_cred;
 606	u8 flags;
 607	struct htc_packet *packet;
 608	unsigned int len;
 609
 610	while (true) {
 611
 612		flags = 0;
 613
 614		if (list_empty(&endpoint->txq))
 615			break;
 616		packet = list_first_entry(&endpoint->txq, struct htc_packet,
 617					  list);
 618
 619		ath6kl_dbg(ATH6KL_DBG_HTC,
 620			   "htc tx got packet 0x%p queue depth %d\n",
 621			   packet, get_queue_depth(&endpoint->txq));
 622
 623		len = CALC_TXRX_PADDED_LEN(target,
 624					   packet->act_len + HTC_HDR_LENGTH);
 625
 626		if (htc_check_credits(target, endpoint, &flags,
 627				      packet->endpoint, len, &req_cred))
 628			break;
 629
 630		/* now we can fully move onto caller's queue */
 631		packet = list_first_entry(&endpoint->txq, struct htc_packet,
 632					  list);
 633		list_move_tail(&packet->list, queue);
 634
 635		/* save the number of credits this packet consumed */
 636		packet->info.tx.cred_used = req_cred;
 637
 638		/* all TX packets are handled asynchronously */
 639		packet->completion = htc_tx_comp_handler;
 640		packet->context = target;
 641		endpoint->ep_st.tx_issued += 1;
 642
 643		/* save send flags */
 644		packet->info.tx.flags = flags;
 645		packet->info.tx.seqno = endpoint->seqno;
 646		endpoint->seqno++;
 647	}
 648}
 649
 650/* See if the padded tx length falls on a credit boundary */
 651static int htc_get_credit_padding(unsigned int cred_sz, int *len,
 652				  struct htc_endpoint *ep)
 653{
 654	int rem_cred, cred_pad;
 655
 656	rem_cred = *len % cred_sz;
 657
 658	/* No padding needed */
 659	if  (!rem_cred)
 660		return 0;
 661
 662	if (!(ep->conn_flags & HTC_FLGS_TX_BNDL_PAD_EN))
 663		return -1;
 664
 665	/*
 666	 * The transfer consumes a "partial" credit, this
 667	 * packet cannot be bundled unless we add
 668	 * additional "dummy" padding (max 255 bytes) to
 669	 * consume the entire credit.
 670	 */
 671	cred_pad = *len < cred_sz ? (cred_sz - *len) : rem_cred;
 672
 673	if ((cred_pad > 0) && (cred_pad <= 255))
 674		*len += cred_pad;
 675	else
 676		/* The amount of padding is too large, send as non-bundled */
 677		return -1;
 678
 679	return cred_pad;
 680}
 681
 682static int ath6kl_htc_tx_setup_scat_list(struct htc_target *target,
 683					 struct htc_endpoint *endpoint,
 684					 struct hif_scatter_req *scat_req,
 685					 int n_scat,
 686					 struct list_head *queue)
 687{
 688	struct htc_packet *packet;
 689	int i, len, rem_scat, cred_pad;
 690	int status = 0;
 691	u8 flags;
 692
 693	rem_scat = target->max_tx_bndl_sz;
 694
 695	for (i = 0; i < n_scat; i++) {
 696		scat_req->scat_list[i].packet = NULL;
 697
 698		if (list_empty(queue))
 699			break;
 700
 701		packet = list_first_entry(queue, struct htc_packet, list);
 702		len = CALC_TXRX_PADDED_LEN(target,
 703					   packet->act_len + HTC_HDR_LENGTH);
 704
 705		cred_pad = htc_get_credit_padding(target->tgt_cred_sz,
 706						  &len, endpoint);
 707		if (cred_pad < 0 || rem_scat < len) {
 708			status = -ENOSPC;
 709			break;
 710		}
 711
 712		rem_scat -= len;
 713		/* now remove it from the queue */
 714		list_del(&packet->list);
 715
 716		scat_req->scat_list[i].packet = packet;
 717		/* prepare packet and flag message as part of a send bundle */
 718		flags = packet->info.tx.flags | HTC_FLAGS_SEND_BUNDLE;
 719		ath6kl_htc_tx_prep_pkt(packet, flags,
 720				       cred_pad, packet->info.tx.seqno);
 721		/* Make sure the buffer is 4-byte aligned */
 722		ath6kl_htc_tx_buf_align(&packet->buf,
 723					packet->act_len + HTC_HDR_LENGTH);
 724		scat_req->scat_list[i].buf = packet->buf;
 725		scat_req->scat_list[i].len = len;
 726
 727		scat_req->len += len;
 728		scat_req->scat_entries++;
 729		ath6kl_dbg(ATH6KL_DBG_HTC,
 730			   "htc tx adding (%d) pkt 0x%p seqno %d len %d remaining %d\n",
 731			   i, packet, packet->info.tx.seqno, len, rem_scat);
 732	}
 733
 734	/* Roll back scatter setup in case of any failure */
 735	if (scat_req->scat_entries < HTC_MIN_HTC_MSGS_TO_BUNDLE) {
 736		for (i = scat_req->scat_entries - 1; i >= 0; i--) {
 737			packet = scat_req->scat_list[i].packet;
 738			if (packet) {
 739				packet->buf += HTC_HDR_LENGTH;
 740				list_add(&packet->list, queue);
 741			}
 742		}
 743		return -EAGAIN;
 744	}
 745
 746	return status;
 747}
 748
 749/*
 750 * Drain a queue and send as bundles this function may return without fully
 751 * draining the queue when
 752 *
 753 *    1. scatter resources are exhausted
 754 *    2. a message that will consume a partial credit will stop the
 755 *    bundling process early
 756 *    3. we drop below the minimum number of messages for a bundle
 757 */
 758static void ath6kl_htc_tx_bundle(struct htc_endpoint *endpoint,
 759				 struct list_head *queue,
 760				 int *sent_bundle, int *n_bundle_pkts)
 761{
 762	struct htc_target *target = endpoint->target;
 763	struct hif_scatter_req *scat_req = NULL;
 764	int n_scat, n_sent_bundle = 0, tot_pkts_bundle = 0, i;
 765	struct htc_packet *packet;
 766	int status;
 767	u32 txb_mask;
 768	u8 ac = WMM_NUM_AC;
 769
 770	if ((HTC_CTRL_RSVD_SVC != endpoint->svc_id) &&
 771	    (WMI_CONTROL_SVC != endpoint->svc_id))
 772		ac = target->dev->ar->ep2ac_map[endpoint->eid];
 773
 774	while (true) {
 775		status = 0;
 776		n_scat = get_queue_depth(queue);
 777		n_scat = min(n_scat, target->msg_per_bndl_max);
 778
 779		if (n_scat < HTC_MIN_HTC_MSGS_TO_BUNDLE)
 780			/* not enough to bundle */
 781			break;
 782
 783		scat_req = hif_scatter_req_get(target->dev->ar);
 784
 785		if (!scat_req) {
 786			/* no scatter resources  */
 787			ath6kl_dbg(ATH6KL_DBG_HTC,
 788				   "htc tx no more scatter resources\n");
 789			break;
 790		}
 791
 792		if ((ac < WMM_NUM_AC) && (ac != WMM_AC_BK)) {
 793			if (WMM_AC_BE == ac)
 794				/*
 795				 * BE, BK have priorities and bit
 796				 * positions reversed
 797				 */
 798				txb_mask = (1 << WMM_AC_BK);
 799			else
 800				/*
 801				 * any AC with priority lower than
 802				 * itself
 803				 */
 804				txb_mask = ((1 << ac) - 1);
 805
 806			/*
 807			 * when the scatter request resources drop below a
 808			 * certain threshold, disable Tx bundling for all
 809			 * AC's with priority lower than the current requesting
 810			 * AC. Otherwise re-enable Tx bundling for them
 811			 */
 812			if (scat_req->scat_q_depth < ATH6KL_SCATTER_REQS)
 813				target->tx_bndl_mask &= ~txb_mask;
 814			else
 815				target->tx_bndl_mask |= txb_mask;
 816		}
 817
 818		ath6kl_dbg(ATH6KL_DBG_HTC, "htc tx pkts to scatter: %d\n",
 819			   n_scat);
 820
 821		scat_req->len = 0;
 822		scat_req->scat_entries = 0;
 823
 824		status = ath6kl_htc_tx_setup_scat_list(target, endpoint,
 825						       scat_req, n_scat,
 826						       queue);
 827		if (status == -EAGAIN) {
 828			hif_scatter_req_add(target->dev->ar, scat_req);
 829			break;
 830		}
 831
 832		/* send path is always asynchronous */
 833		scat_req->complete = htc_async_tx_scat_complete;
 834		n_sent_bundle++;
 835		tot_pkts_bundle += scat_req->scat_entries;
 836
 837		ath6kl_dbg(ATH6KL_DBG_HTC,
 838			   "htc tx scatter bytes %d entries %d\n",
 839			   scat_req->len, scat_req->scat_entries);
 840
 841		for (i = 0; i < scat_req->scat_entries; i++) {
 842			packet = scat_req->scat_list[i].packet;
 843			trace_ath6kl_htc_tx(packet->status, packet->endpoint,
 844					    packet->buf, packet->act_len);
 845		}
 846
 847		ath6kl_hif_submit_scat_req(target->dev, scat_req, false);
 848
 849		if (status)
 850			break;
 851	}
 852
 853	*sent_bundle = n_sent_bundle;
 854	*n_bundle_pkts = tot_pkts_bundle;
 855	ath6kl_dbg(ATH6KL_DBG_HTC, "htc tx bundle sent %d pkts\n",
 856		   n_sent_bundle);
 857
 858	return;
 859}
 860
 861static void ath6kl_htc_tx_from_queue(struct htc_target *target,
 862				     struct htc_endpoint *endpoint)
 863{
 864	struct list_head txq;
 865	struct htc_packet *packet;
 866	int bundle_sent;
 867	int n_pkts_bundle;
 868	u8 ac = WMM_NUM_AC;
 869	int status;
 870
 871	spin_lock_bh(&target->tx_lock);
 872
 873	endpoint->tx_proc_cnt++;
 874	if (endpoint->tx_proc_cnt > 1) {
 875		endpoint->tx_proc_cnt--;
 876		spin_unlock_bh(&target->tx_lock);
 877		ath6kl_dbg(ATH6KL_DBG_HTC, "htc tx busy\n");
 878		return;
 879	}
 880
 881	/*
 882	 * drain the endpoint TX queue for transmission as long
 883	 * as we have enough credits.
 884	 */
 885	INIT_LIST_HEAD(&txq);
 886
 887	if ((HTC_CTRL_RSVD_SVC != endpoint->svc_id) &&
 888	    (WMI_CONTROL_SVC != endpoint->svc_id))
 889		ac = target->dev->ar->ep2ac_map[endpoint->eid];
 890
 891	while (true) {
 892
 893		if (list_empty(&endpoint->txq))
 894			break;
 895
 896		ath6kl_htc_tx_pkts_get(target, endpoint, &txq);
 897
 898		if (list_empty(&txq))
 899			break;
 900
 901		spin_unlock_bh(&target->tx_lock);
 902
 903		bundle_sent = 0;
 904		n_pkts_bundle = 0;
 905
 906		while (true) {
 907			/* try to send a bundle on each pass */
 908			if ((target->tx_bndl_mask) &&
 909			    (get_queue_depth(&txq) >=
 910			    HTC_MIN_HTC_MSGS_TO_BUNDLE)) {
 911				int temp1 = 0, temp2 = 0;
 912
 913				/* check if bundling is enabled for an AC */
 914				if (target->tx_bndl_mask & (1 << ac)) {
 915					ath6kl_htc_tx_bundle(endpoint, &txq,
 916							     &temp1, &temp2);
 917					bundle_sent += temp1;
 918					n_pkts_bundle += temp2;
 919				}
 920			}
 921
 922			if (list_empty(&txq))
 923				break;
 924
 925			packet = list_first_entry(&txq, struct htc_packet,
 926						  list);
 927			list_del(&packet->list);
 928
 929			ath6kl_htc_tx_prep_pkt(packet, packet->info.tx.flags,
 930					       0, packet->info.tx.seqno);
 931			status = ath6kl_htc_tx_issue(target, packet);
 932
 933			if (status) {
 934				packet->status = status;
 935				packet->completion(packet->context, packet);
 936			}
 937		}
 938
 939		spin_lock_bh(&target->tx_lock);
 940
 941		endpoint->ep_st.tx_bundles += bundle_sent;
 942		endpoint->ep_st.tx_pkt_bundled += n_pkts_bundle;
 943
 944		/*
 945		 * if an AC has bundling disabled and no tx bundling
 946		 * has occured continously for a certain number of TX,
 947		 * enable tx bundling for this AC
 948		 */
 949		if (!bundle_sent) {
 950			if (!(target->tx_bndl_mask & (1 << ac)) &&
 951			    (ac < WMM_NUM_AC)) {
 952				if (++target->ac_tx_count[ac] >=
 953					TX_RESUME_BUNDLE_THRESHOLD) {
 954					target->ac_tx_count[ac] = 0;
 955					target->tx_bndl_mask |= (1 << ac);
 956				}
 957			}
 958		} else {
 959			/* tx bundling will reset the counter */
 960			if (ac < WMM_NUM_AC)
 961				target->ac_tx_count[ac] = 0;
 962		}
 963	}
 964
 965	endpoint->tx_proc_cnt = 0;
 966	spin_unlock_bh(&target->tx_lock);
 967}
 968
 969static bool ath6kl_htc_tx_try(struct htc_target *target,
 970			      struct htc_endpoint *endpoint,
 971			      struct htc_packet *tx_pkt)
 972{
 973	struct htc_ep_callbacks ep_cb;
 974	int txq_depth;
 975	bool overflow = false;
 976
 977	ep_cb = endpoint->ep_cb;
 978
 979	spin_lock_bh(&target->tx_lock);
 980	txq_depth = get_queue_depth(&endpoint->txq);
 981	spin_unlock_bh(&target->tx_lock);
 982
 983	if (txq_depth >= endpoint->max_txq_depth)
 984		overflow = true;
 985
 986	if (overflow)
 987		ath6kl_dbg(ATH6KL_DBG_HTC,
 988			   "htc tx overflow ep %d depth %d max %d\n",
 989			   endpoint->eid, txq_depth,
 990			   endpoint->max_txq_depth);
 991
 992	if (overflow && ep_cb.tx_full) {
 993		if (ep_cb.tx_full(endpoint->target, tx_pkt) ==
 994		    HTC_SEND_FULL_DROP) {
 995			endpoint->ep_st.tx_dropped += 1;
 996			return false;
 997		}
 998	}
 999
1000	spin_lock_bh(&target->tx_lock);
1001	list_add_tail(&tx_pkt->list, &endpoint->txq);
1002	spin_unlock_bh(&target->tx_lock);
1003
1004	ath6kl_htc_tx_from_queue(target, endpoint);
1005
1006	return true;
1007}
1008
1009static void htc_chk_ep_txq(struct htc_target *target)
1010{
1011	struct htc_endpoint *endpoint;
1012	struct htc_endpoint_credit_dist *cred_dist;
1013
1014	/*
1015	 * Run through the credit distribution list to see if there are
1016	 * packets queued. NOTE: no locks need to be taken since the
1017	 * distribution list is not dynamic (cannot be re-ordered) and we
1018	 * are not modifying any state.
1019	 */
1020	list_for_each_entry(cred_dist, &target->cred_dist_list, list) {
1021		endpoint = cred_dist->htc_ep;
1022
1023		spin_lock_bh(&target->tx_lock);
1024		if (!list_empty(&endpoint->txq)) {
1025			ath6kl_dbg(ATH6KL_DBG_HTC,
1026				   "htc creds ep %d credits %d pkts %d\n",
1027				   cred_dist->endpoint,
1028				   endpoint->cred_dist.credits,
1029				   get_queue_depth(&endpoint->txq));
1030			spin_unlock_bh(&target->tx_lock);
1031			/*
1032			 * Try to start the stalled queue, this list is
1033			 * ordered by priority. If there are credits
1034			 * available the highest priority queue will get a
1035			 * chance to reclaim credits from lower priority
1036			 * ones.
1037			 */
1038			ath6kl_htc_tx_from_queue(target, endpoint);
1039			spin_lock_bh(&target->tx_lock);
1040		}
1041		spin_unlock_bh(&target->tx_lock);
1042	}
1043}
1044
1045static int htc_setup_tx_complete(struct htc_target *target)
1046{
1047	struct htc_packet *send_pkt = NULL;
1048	int status;
1049
1050	send_pkt = htc_get_control_buf(target, true);
1051
1052	if (!send_pkt)
1053		return -ENOMEM;
1054
1055	if (target->htc_tgt_ver >= HTC_VERSION_2P1) {
1056		struct htc_setup_comp_ext_msg *setup_comp_ext;
1057		u32 flags = 0;
1058
1059		setup_comp_ext =
1060		    (struct htc_setup_comp_ext_msg *)send_pkt->buf;
1061		memset(setup_comp_ext, 0, sizeof(*setup_comp_ext));
1062		setup_comp_ext->msg_id =
1063			cpu_to_le16(HTC_MSG_SETUP_COMPLETE_EX_ID);
1064
1065		if (target->msg_per_bndl_max > 0) {
1066			/* Indicate HTC bundling to the target */
1067			flags |= HTC_SETUP_COMP_FLG_RX_BNDL_EN;
1068			setup_comp_ext->msg_per_rxbndl =
1069						target->msg_per_bndl_max;
1070		}
1071
1072		memcpy(&setup_comp_ext->flags, &flags,
1073		       sizeof(setup_comp_ext->flags));
1074		set_htc_pkt_info(send_pkt, NULL, (u8 *) setup_comp_ext,
1075				 sizeof(struct htc_setup_comp_ext_msg),
1076				 ENDPOINT_0, HTC_SERVICE_TX_PACKET_TAG);
1077
1078	} else {
1079		struct htc_setup_comp_msg *setup_comp;
1080		setup_comp = (struct htc_setup_comp_msg *)send_pkt->buf;
1081		memset(setup_comp, 0, sizeof(struct htc_setup_comp_msg));
1082		setup_comp->msg_id = cpu_to_le16(HTC_MSG_SETUP_COMPLETE_ID);
1083		set_htc_pkt_info(send_pkt, NULL, (u8 *) setup_comp,
1084				 sizeof(struct htc_setup_comp_msg),
1085				 ENDPOINT_0, HTC_SERVICE_TX_PACKET_TAG);
1086	}
1087
1088	/* we want synchronous operation */
1089	send_pkt->completion = NULL;
1090	ath6kl_htc_tx_prep_pkt(send_pkt, 0, 0, 0);
1091	status = ath6kl_htc_tx_issue(target, send_pkt);
1092
1093	if (send_pkt != NULL)
1094		htc_reclaim_txctrl_buf(target, send_pkt);
1095
1096	return status;
1097}
1098
1099static void ath6kl_htc_set_credit_dist(struct htc_target *target,
1100				struct ath6kl_htc_credit_info *credit_info,
1101				u16 srvc_pri_order[], int list_len)
1102{
1103	struct htc_endpoint *endpoint;
1104	int i, ep;
1105
1106	target->credit_info = credit_info;
1107
1108	list_add_tail(&target->endpoint[ENDPOINT_0].cred_dist.list,
1109		      &target->cred_dist_list);
1110
1111	for (i = 0; i < list_len; i++) {
1112		for (ep = ENDPOINT_1; ep < ENDPOINT_MAX; ep++) {
1113			endpoint = &target->endpoint[ep];
1114			if (endpoint->svc_id == srvc_pri_order[i]) {
1115				list_add_tail(&endpoint->cred_dist.list,
1116					      &target->cred_dist_list);
1117				break;
1118			}
1119		}
1120		if (ep >= ENDPOINT_MAX) {
1121			WARN_ON(1);
1122			return;
1123		}
1124	}
1125}
1126
1127static int ath6kl_htc_mbox_tx(struct htc_target *target,
1128			      struct htc_packet *packet)
1129{
1130	struct htc_endpoint *endpoint;
1131	struct list_head queue;
1132
1133	ath6kl_dbg(ATH6KL_DBG_HTC,
1134		   "htc tx ep id %d buf 0x%p len %d\n",
1135		   packet->endpoint, packet->buf, packet->act_len);
1136
1137	if (packet->endpoint >= ENDPOINT_MAX) {
1138		WARN_ON(1);
1139		return -EINVAL;
1140	}
1141
1142	endpoint = &target->endpoint[packet->endpoint];
1143
1144	if (!ath6kl_htc_tx_try(target, endpoint, packet)) {
1145		packet->status = (target->htc_flags & HTC_OP_STATE_STOPPING) ?
1146				 -ECANCELED : -ENOSPC;
1147		INIT_LIST_HEAD(&queue);
1148		list_add(&packet->list, &queue);
1149		htc_tx_complete(endpoint, &queue);
1150	}
1151
1152	return 0;
1153}
1154
1155/* flush endpoint TX queue */
1156static void ath6kl_htc_mbox_flush_txep(struct htc_target *target,
1157			   enum htc_endpoint_id eid, u16 tag)
1158{
1159	struct htc_packet *packet, *tmp_pkt;
1160	struct list_head discard_q, container;
1161	struct htc_endpoint *endpoint = &target->endpoint[eid];
1162
1163	if (!endpoint->svc_id) {
1164		WARN_ON(1);
1165		return;
1166	}
1167
1168	/* initialize the discard queue */
1169	INIT_LIST_HEAD(&discard_q);
1170
1171	spin_lock_bh(&target->tx_lock);
1172
1173	list_for_each_entry_safe(packet, tmp_pkt, &endpoint->txq, list) {
1174		if ((tag == HTC_TX_PACKET_TAG_ALL) ||
1175		    (tag == packet->info.tx.tag))
1176			list_move_tail(&packet->list, &discard_q);
1177	}
1178
1179	spin_unlock_bh(&target->tx_lock);
1180
1181	list_for_each_entry_safe(packet, tmp_pkt, &discard_q, list) {
1182		packet->status = -ECANCELED;
1183		list_del(&packet->list);
1184		ath6kl_dbg(ATH6KL_DBG_HTC,
1185			   "htc tx flushing pkt 0x%p len %d  ep %d tag 0x%x\n",
1186			   packet, packet->act_len,
1187			   packet->endpoint, packet->info.tx.tag);
1188
1189		INIT_LIST_HEAD(&container);
1190		list_add_tail(&packet->list, &container);
1191		htc_tx_complete(endpoint, &container);
1192	}
1193
1194}
1195
1196static void ath6kl_htc_flush_txep_all(struct htc_target *target)
1197{
1198	struct htc_endpoint *endpoint;
1199	int i;
1200
1201	dump_cred_dist_stats(target);
1202
1203	for (i = ENDPOINT_0; i < ENDPOINT_MAX; i++) {
1204		endpoint = &target->endpoint[i];
1205		if (endpoint->svc_id == 0)
1206			/* not in use.. */
1207			continue;
1208		ath6kl_htc_mbox_flush_txep(target, i, HTC_TX_PACKET_TAG_ALL);
1209	}
1210}
1211
1212static void ath6kl_htc_mbox_activity_changed(struct htc_target *target,
1213					     enum htc_endpoint_id eid,
1214					     bool active)
1215{
1216	struct htc_endpoint *endpoint = &target->endpoint[eid];
1217	bool dist = false;
1218
1219	if (endpoint->svc_id == 0) {
1220		WARN_ON(1);
1221		return;
1222	}
1223
1224	spin_lock_bh(&target->tx_lock);
1225
1226	if (active) {
1227		if (!(endpoint->cred_dist.dist_flags & HTC_EP_ACTIVE)) {
1228			endpoint->cred_dist.dist_flags |= HTC_EP_ACTIVE;
1229			dist = true;
1230		}
1231	} else {
1232		if (endpoint->cred_dist.dist_flags & HTC_EP_ACTIVE) {
1233			endpoint->cred_dist.dist_flags &= ~HTC_EP_ACTIVE;
1234			dist = true;
1235		}
1236	}
1237
1238	if (dist) {
1239		endpoint->cred_dist.txq_depth =
1240			get_queue_depth(&endpoint->txq);
1241
1242		ath6kl_dbg(ATH6KL_DBG_HTC,
1243			   "htc tx activity ctxt 0x%p dist 0x%p\n",
1244			   target->credit_info, &target->cred_dist_list);
1245
1246		ath6kl_credit_distribute(target->credit_info,
1247					 &target->cred_dist_list,
1248					 HTC_CREDIT_DIST_ACTIVITY_CHANGE);
1249	}
1250
1251	spin_unlock_bh(&target->tx_lock);
1252
1253	if (dist && !active)
1254		htc_chk_ep_txq(target);
1255}
1256
1257/* HTC Rx */
1258
1259static inline void ath6kl_htc_rx_update_stats(struct htc_endpoint *endpoint,
1260					      int n_look_ahds)
1261{
1262	endpoint->ep_st.rx_pkts++;
1263	if (n_look_ahds == 1)
1264		endpoint->ep_st.rx_lkahds++;
1265	else if (n_look_ahds > 1)
1266		endpoint->ep_st.rx_bundle_lkahd++;
1267}
1268
1269static inline bool htc_valid_rx_frame_len(struct htc_target *target,
1270					  enum htc_endpoint_id eid, int len)
1271{
1272	return (eid == target->dev->ar->ctrl_ep) ?
1273		len <= ATH6KL_BUFFER_SIZE : len <= ATH6KL_AMSDU_BUFFER_SIZE;
1274}
1275
1276static int htc_add_rxbuf(struct htc_target *target, struct htc_packet *packet)
1277{
1278	struct list_head queue;
1279
1280	INIT_LIST_HEAD(&queue);
1281	list_add_tail(&packet->list, &queue);
1282	return ath6kl_htc_mbox_add_rxbuf_multiple(target, &queue);
1283}
1284
1285static void htc_reclaim_rxbuf(struct htc_target *target,
1286			      struct htc_packet *packet,
1287			      struct htc_endpoint *ep)
1288{
1289	if (packet->info.rx.rx_flags & HTC_RX_PKT_NO_RECYCLE) {
1290		htc_rxpkt_reset(packet);
1291		packet->status = -ECANCELED;
1292		ep->ep_cb.rx(ep->target, packet);
1293	} else {
1294		htc_rxpkt_reset(packet);
1295		htc_add_rxbuf((void *)(target), packet);
1296	}
1297}
1298
1299static void reclaim_rx_ctrl_buf(struct htc_target *target,
1300				struct htc_packet *packet)
1301{
1302	spin_lock_bh(&target->htc_lock);
1303	list_add_tail(&packet->list, &target->free_ctrl_rxbuf);
1304	spin_unlock_bh(&target->htc_lock);
1305}
1306
1307static int ath6kl_htc_rx_packet(struct htc_target *target,
1308				struct htc_packet *packet,
1309				u32 rx_len)
1310{
1311	struct ath6kl_device *dev = target->dev;
1312	u32 padded_len;
1313	int status;
1314
1315	padded_len = CALC_TXRX_PADDED_LEN(target, rx_len);
1316
1317	if (padded_len > packet->buf_len) {
1318		ath6kl_err("not enough receive space for packet - padlen %d recvlen %d bufferlen %d\n",
1319			   padded_len, rx_len, packet->buf_len);
1320		return -ENOMEM;
1321	}
1322
1323	ath6kl_dbg(ATH6KL_DBG_HTC,
1324		   "htc rx 0x%p hdr 0x%x len %d mbox 0x%x\n",
1325		   packet, packet->info.rx.exp_hdr,
1326		   padded_len, dev->ar->mbox_info.htc_addr);
1327
1328	status = hif_read_write_sync(dev->ar,
1329				     dev->ar->mbox_info.htc_addr,
1330				     packet->buf, padded_len,
1331				     HIF_RD_SYNC_BLOCK_FIX);
1332
1333	packet->status = status;
1334
1335	return status;
1336}
1337
1338/*
1339 * optimization for recv packets, we can indicate a
1340 * "hint" that there are more  single-packets to fetch
1341 * on this endpoint.
1342 */
1343static void ath6kl_htc_rx_set_indicate(u32 lk_ahd,
1344				       struct htc_endpoint *endpoint,
1345				       struct htc_packet *packet)
1346{
1347	struct htc_frame_hdr *htc_hdr = (struct htc_frame_hdr *)&lk_ahd;
1348
1349	if (htc_hdr->eid == packet->endpoint) {
1350		if (!list_empty(&endpoint->rx_bufq))
1351			packet->info.rx.indicat_flags |=
1352					HTC_RX_FLAGS_INDICATE_MORE_PKTS;
1353	}
1354}
1355
1356static void ath6kl_htc_rx_chk_water_mark(struct htc_endpoint *endpoint)
1357{
1358	struct htc_ep_callbacks ep_cb = endpoint->ep_cb;
1359
1360	if (ep_cb.rx_refill_thresh > 0) {
1361		spin_lock_bh(&endpoint->target->rx_lock);
1362		if (get_queue_depth(&endpoint->rx_bufq)
1363		    < ep_cb.rx_refill_thresh) {
1364			spin_unlock_bh(&endpoint->target->rx_lock);
1365			ep_cb.rx_refill(endpoint->target, endpoint->eid);
1366			return;
1367		}
1368		spin_unlock_bh(&endpoint->target->rx_lock);
1369	}
1370}
1371
1372/* This function is called with rx_lock held */
1373static int ath6kl_htc_rx_setup(struct htc_target *target,
1374			       struct htc_endpoint *ep,
1375			       u32 *lk_ahds, struct list_head *queue, int n_msg)
1376{
1377	struct htc_packet *packet;
1378	/* FIXME: type of lk_ahds can't be right */
1379	struct htc_frame_hdr *htc_hdr = (struct htc_frame_hdr *)lk_ahds;
1380	struct htc_ep_callbacks ep_cb;
1381	int status = 0, j, full_len;
1382	bool no_recycle;
1383
1384	full_len = CALC_TXRX_PADDED_LEN(target,
1385					le16_to_cpu(htc_hdr->payld_len) +
1386					sizeof(*htc_hdr));
1387
1388	if (!htc_valid_rx_frame_len(target, ep->eid, full_len)) {
1389		ath6kl_warn("Rx buffer requested with invalid length htc_hdr:eid %d, flags 0x%x, len %d\n",
1390			    htc_hdr->eid, htc_hdr->flags,
1391			    le16_to_cpu(htc_hdr->payld_len));
1392		return -EINVAL;
1393	}
1394
1395	ep_cb = ep->ep_cb;
1396	for (j = 0; j < n_msg; j++) {
1397
1398		/*
1399		 * Reset flag, any packets allocated using the
1400		 * rx_alloc() API cannot be recycled on
1401		 * cleanup,they must be explicitly returned.
1402		 */
1403		no_recycle = false;
1404
1405		if (ep_cb.rx_allocthresh &&
1406		    (full_len > ep_cb.rx_alloc_thresh)) {
1407			ep->ep_st.rx_alloc_thresh_hit += 1;
1408			ep->ep_st.rxalloc_thresh_byte +=
1409				le16_to_cpu(htc_hdr->payld_len);
1410
1411			spin_unlock_bh(&target->rx_lock);
1412			no_recycle = true;
1413
1414			packet = ep_cb.rx_allocthresh(ep->target, ep->eid,
1415						      full_len);
1416			spin_lock_bh(&target->rx_lock);
1417		} else {
1418			/* refill handler is being used */
1419			if (list_empty(&ep->rx_bufq)) {
1420				if (ep_cb.rx_refill) {
1421					spin_unlock_bh(&target->rx_lock);
1422					ep_cb.rx_refill(ep->target, ep->eid);
1423					spin_lock_bh(&target->rx_lock);
1424				}
1425			}
1426
1427			if (list_empty(&ep->rx_bufq))
1428				packet = NULL;
1429			else {
1430				packet = list_first_entry(&ep->rx_bufq,
1431						struct htc_packet, list);
1432				list_del(&packet->list);
1433			}
1434		}
1435
1436		if (!packet) {
1437			target->rx_st_flags |= HTC_RECV_WAIT_BUFFERS;
1438			target->ep_waiting = ep->eid;
1439			return -ENOSPC;
1440		}
1441
1442		/* clear flags */
1443		packet->info.rx.rx_flags = 0;
1444		packet->info.rx.indicat_flags = 0;
1445		packet->status = 0;
1446
1447		if (no_recycle)
1448			/*
1449			 * flag that these packets cannot be
1450			 * recycled, they have to be returned to
1451			 * the user
1452			 */
1453			packet->info.rx.rx_flags |= HTC_RX_PKT_NO_RECYCLE;
1454
1455		/* Caller needs to free this upon any failure */
1456		list_add_tail(&packet->list, queue);
1457
1458		if (target->htc_flags & HTC_OP_STATE_STOPPING) {
1459			status = -ECANCELED;
1460			break;
1461		}
1462
1463		if (j) {
1464			packet->info.rx.rx_flags |= HTC_RX_PKT_REFRESH_HDR;
1465			packet->info.rx.exp_hdr = 0xFFFFFFFF;
1466		} else
1467			/* set expected look ahead */
1468			packet->info.rx.exp_hdr = *lk_ahds;
1469
1470		packet->act_len = le16_to_cpu(htc_hdr->payld_len) +
1471			HTC_HDR_LENGTH;
1472	}
1473
1474	return status;
1475}
1476
1477static int ath6kl_htc_rx_alloc(struct htc_target *target,
1478			       u32 lk_ahds[], int msg,
1479			       struct htc_endpoint *endpoint,
1480			       struct list_head *queue)
1481{
1482	int status = 0;
1483	struct htc_packet *packet, *tmp_pkt;
1484	struct htc_frame_hdr *htc_hdr;
1485	int i, n_msg;
1486
1487	spin_lock_bh(&target->rx_lock);
1488
1489	for (i = 0; i < msg; i++) {
1490
1491		htc_hdr = (struct htc_frame_hdr *)&lk_ahds[i];
1492
1493		if (htc_hdr->eid >= ENDPOINT_MAX) {
1494			ath6kl_err("invalid ep in look-ahead: %d\n",
1495				   htc_hdr->eid);
1496			status = -ENOMEM;
1497			break;
1498		}
1499
1500		if (htc_hdr->eid != endpoint->eid) {
1501			ath6kl_err("invalid ep in look-ahead: %d should be : %d (index:%d)\n",
1502				   htc_hdr->eid, endpoint->eid, i);
1503			status = -ENOMEM;
1504			break;
1505		}
1506
1507		if (le16_to_cpu(htc_hdr->payld_len) > HTC_MAX_PAYLOAD_LENGTH) {
1508			ath6kl_err("payload len %d exceeds max htc : %d !\n",
1509				   htc_hdr->payld_len,
1510				   (u32) HTC_MAX_PAYLOAD_LENGTH);
1511			status = -ENOMEM;
1512			break;
1513		}
1514
1515		if (endpoint->svc_id == 0) {
1516			ath6kl_err("ep %d is not connected !\n", htc_hdr->eid);
1517			status = -ENOMEM;
1518			break;
1519		}
1520
1521		if (htc_hdr->flags & HTC_FLG_RX_BNDL_CNT) {
1522			/*
1523			 * HTC header indicates that every packet to follow
1524			 * has the same padded length so that it can be
1525			 * optimally fetched as a full bundle.
1526			 */
1527			n_msg = (htc_hdr->flags & HTC_FLG_RX_BNDL_CNT) >>
1528				HTC_FLG_RX_BNDL_CNT_S;
1529
1530			/* the count doesn't include the starter frame */
1531			n_msg++;
1532			if (n_msg > target->msg_per_bndl_max) {
1533				status = -ENOMEM;
1534				break;
1535			}
1536
1537			endpoint->ep_st.rx_bundle_from_hdr += 1;
1538			ath6kl_dbg(ATH6KL_DBG_HTC,
1539				   "htc rx bundle pkts %d\n",
1540				   n_msg);
1541		} else
1542			/* HTC header only indicates 1 message to fetch */
1543			n_msg = 1;
1544
1545		/* Setup packet buffers for each message */
1546		status = ath6kl_htc_rx_setup(target, endpoint, &lk_ahds[i],
1547					     queue, n_msg);
1548
1549		/*
1550		 * This is due to unavailabilty of buffers to rx entire data.
1551		 * Return no error so that free buffers from queue can be used
1552		 * to receive partial data.
1553		 */
1554		if (status == -ENOSPC) {
1555			spin_unlock_bh(&target->rx_lock);
1556			return 0;
1557		}
1558
1559		if (status)
1560			break;
1561	}
1562
1563	spin_unlock_bh(&target->rx_lock);
1564
1565	if (status) {
1566		list_for_each_entry_safe(packet, tmp_pkt, queue, list) {
1567			list_del(&packet->list);
1568			htc_reclaim_rxbuf(target, packet,
1569					  &target->endpoint[packet->endpoint]);
1570		}
1571	}
1572
1573	return status;
1574}
1575
1576static void htc_ctrl_rx(struct htc_target *context, struct htc_packet *packets)
1577{
1578	if (packets->endpoint != ENDPOINT_0) {
1579		WARN_ON(1);
1580		return;
1581	}
1582
1583	if (packets->status == -ECANCELED) {
1584		reclaim_rx_ctrl_buf(context, packets);
1585		return;
1586	}
1587
1588	if (packets->act_len > 0) {
1589		ath6kl_err("htc_ctrl_rx, got message with len:%zu\n",
1590			   packets->act_len + HTC_HDR_LENGTH);
1591
1592		ath6kl_dbg_dump(ATH6KL_DBG_HTC,
1593				"htc rx unexpected endpoint 0 message", "",
1594				packets->buf - HTC_HDR_LENGTH,
1595				packets->act_len + HTC_HDR_LENGTH);
1596	}
1597
1598	htc_reclaim_rxbuf(context, packets, &context->endpoint[0]);
1599}
1600
1601static void htc_proc_cred_rpt(struct htc_target *target,
1602			      struct htc_credit_report *rpt,
1603			      int n_entries,
1604			      enum htc_endpoint_id from_ep)
1605{
1606	struct htc_endpoint *endpoint;
1607	int tot_credits = 0, i;
1608	bool dist = false;
1609
1610	spin_lock_bh(&target->tx_lock);
1611
1612	for (i = 0; i < n_entries; i++, rpt++) {
1613		if (rpt->eid >= ENDPOINT_MAX) {
1614			WARN_ON(1);
1615			spin_unlock_bh(&target->tx_lock);
1616			return;
1617		}
1618
1619		endpoint = &target->endpoint[rpt->eid];
1620
1621		ath6kl_dbg(ATH6KL_DBG_CREDIT,
1622			   "credit report ep %d credits %d\n",
1623			   rpt->eid, rpt->credits);
1624
1625		endpoint->ep_st.tx_cred_rpt += 1;
1626		endpoint->ep_st.cred_retnd += rpt->credits;
1627
1628		if (from_ep == rpt->eid) {
1629			/*
1630			 * This credit report arrived on the same endpoint
1631			 * indicating it arrived in an RX packet.
1632			 */
1633			endpoint->ep_st.cred_from_rx += rpt->credits;
1634			endpoint->ep_st.cred_rpt_from_rx += 1;
1635		} else if (from_ep == ENDPOINT_0) {
1636			/* credit arrived on endpoint 0 as a NULL message */
1637			endpoint->ep_st.cred_from_ep0 += rpt->credits;
1638			endpoint->ep_st.cred_rpt_ep0 += 1;
1639		} else {
1640			endpoint->ep_st.cred_from_other += rpt->credits;
1641			endpoint->ep_st.cred_rpt_from_other += 1;
1642		}
1643
1644		if (rpt->eid == ENDPOINT_0)
1645			/* always give endpoint 0 credits back */
1646			endpoint->cred_dist.credits += rpt->credits;
1647		else {
1648			endpoint->cred_dist.cred_to_dist += rpt->credits;
1649			dist = true;
1650		}
1651
1652		/*
1653		 * Refresh tx depth for distribution function that will
1654		 * recover these credits NOTE: this is only valid when
1655		 * there are credits to recover!
1656		 */
1657		endpoint->cred_dist.txq_depth =
1658			get_queue_depth(&endpoint->txq);
1659
1660		tot_credits += rpt->credits;
1661	}
1662
1663	if (dist) {
1664		/*
1665		 * This was a credit return based on a completed send
1666		 * operations note, this is done with the lock held
1667		 */
1668		ath6kl_credit_distribute(target->credit_info,
1669					 &target->cred_dist_list,
1670					 HTC_CREDIT_DIST_SEND_COMPLETE);
1671	}
1672
1673	spin_unlock_bh(&target->tx_lock);
1674
1675	if (tot_credits)
1676		htc_chk_ep_txq(target);
1677}
1678
1679static int htc_parse_trailer(struct htc_target *target,
1680			     struct htc_record_hdr *record,
1681			     u8 *record_buf, u32 *next_lk_ahds,
1682			     enum htc_endpoint_id endpoint,
1683			     int *n_lk_ahds)
1684{
1685	struct htc_bundle_lkahd_rpt *bundle_lkahd_rpt;
1686	struct htc_lookahead_report *lk_ahd;
1687	int len;
1688
1689	switch (record->rec_id) {
1690	case HTC_RECORD_CREDITS:
1691		len = record->len / sizeof(struct htc_credit_report);
1692		if (!len) {
1693			WARN_ON(1);
1694			return -EINVAL;
1695		}
1696
1697		htc_proc_cred_rpt(target,
1698				  (struct htc_credit_report *) record_buf,
1699				  len, endpoint);
1700		break;
1701	case HTC_RECORD_LOOKAHEAD:
1702		len = record->len / sizeof(*lk_ahd);
1703		if (!len) {
1704			WARN_ON(1);
1705			return -EINVAL;
1706		}
1707
1708		lk_ahd = (struct htc_lookahead_report *) record_buf;
1709		if ((lk_ahd->pre_valid == ((~lk_ahd->post_valid) & 0xFF)) &&
1710		    next_lk_ahds) {
1711
1712			ath6kl_dbg(ATH6KL_DBG_HTC,
1713				   "htc rx lk_ahd found pre_valid 0x%x post_valid 0x%x\n",
1714				   lk_ahd->pre_valid, lk_ahd->post_valid);
1715
1716			/* look ahead bytes are valid, copy them over */
1717			memcpy((u8 *)&next_lk_ahds[0], lk_ahd->lk_ahd, 4);
1718
1719			ath6kl_dbg_dump(ATH6KL_DBG_HTC,
1720					"htc rx next look ahead",
1721					"", next_lk_ahds, 4);
1722
1723			*n_lk_ahds = 1;
1724		}
1725		break;
1726	case HTC_RECORD_LOOKAHEAD_BUNDLE:
1727		len = record->len / sizeof(*bundle_lkahd_rpt);
1728		if (!len || (len > HTC_HOST_MAX_MSG_PER_BUNDLE)) {
1729			WARN_ON(1);
1730			return -EINVAL;
1731		}
1732
1733		if (next_lk_ahds) {
1734			int i;
1735
1736			bundle_lkahd_rpt =
1737				(struct htc_bundle_lkahd_rpt *) record_buf;
1738
1739			ath6kl_dbg_dump(ATH6KL_DBG_HTC, "htc rx bundle lk_ahd",
1740					"", record_buf, record->len);
1741
1742			for (i = 0; i < len; i++) {
1743				memcpy((u8 *)&next_lk_ahds[i],
1744				       bundle_lkahd_rpt->lk_ahd, 4);
1745				bundle_lkahd_rpt++;
1746			}
1747
1748			*n_lk_ahds = i;
1749		}
1750		break;
1751	default:
1752		ath6kl_err("unhandled record: id:%d len:%d\n",
1753			   record->rec_id, record->len);
1754		break;
1755	}
1756
1757	return 0;
1758
1759}
1760
1761static int htc_proc_trailer(struct htc_target *target,
1762			    u8 *buf, int len, u32 *next_lk_ahds,
1763			    int *n_lk_ahds, enum htc_endpoint_id endpoint)
1764{
1765	struct htc_record_hdr *record;
1766	int orig_len;
1767	int status;
1768	u8 *record_buf;
1769	u8 *orig_buf;
1770
1771	ath6kl_dbg(ATH6KL_DBG_HTC, "htc rx trailer len %d\n", len);
1772	ath6kl_dbg_dump(ATH6KL_DBG_HTC, NULL, "", buf, len);
1773
1774	orig_buf = buf;
1775	orig_len = len;
1776	status = 0;
1777
1778	while (len > 0) {
1779
1780		if (len < sizeof(struct htc_record_hdr)) {
1781			status = -ENOMEM;
1782			break;
1783		}
1784		/* these are byte aligned structs */
1785		record = (struct htc_record_hdr *) buf;
1786		len -= sizeof(struct htc_record_hdr);
1787		buf += sizeof(struct htc_record_hdr);
1788
1789		if (record->len > len) {
1790			ath6kl_err("invalid record len: %d (id:%d) buf has: %d bytes left\n",
1791				   record->len, record->rec_id, len);
1792			status = -ENOMEM;
1793			break;
1794		}
1795		record_buf = buf;
1796
1797		status = htc_parse_trailer(target, record, record_buf,
1798					   next_lk_ahds, endpoint, n_lk_ahds);
1799
1800		if (status)
1801			break;
1802
1803		/* advance buffer past this record for next time around */
1804		buf += record->len;
1805		len -= record->len;
1806	}
1807
1808	if (status)
1809		ath6kl_dbg_dump(ATH6KL_DBG_HTC, "htc rx bad trailer",
1810				"", orig_buf, orig_len);
1811
1812	return status;
1813}
1814
1815static int ath6kl_htc_rx_process_hdr(struct htc_target *target,
1816				     struct htc_packet *packet,
1817				     u32 *next_lkahds, int *n_lkahds)
1818{
1819	int status = 0;
1820	u16 payload_len;
1821	u32 lk_ahd;
1822	struct htc_frame_hdr *htc_hdr = (struct htc_frame_hdr *)packet->buf;
1823
1824	if (n_lkahds != NULL)
1825		*n_lkahds = 0;
1826
1827	/*
1828	 * NOTE: we cannot assume the alignment of buf, so we use the safe
1829	 * macros to retrieve 16 bit fields.
1830	 */
1831	payload_len = le16_to_cpu(get_unaligned(&htc_hdr->payld_len));
1832
1833	memcpy((u8 *)&lk_ahd, packet->buf, sizeof(lk_ahd));
1834
1835	if (packet->info.rx.rx_flags & HTC_RX_PKT_REFRESH_HDR) {
1836		/*
1837		 * Refresh the expected header and the actual length as it
1838		 * was unknown when this packet was grabbed as part of the
1839		 * bundle.
1840		 */
1841		packet->info.rx.exp_hdr = lk_ahd;
1842		packet->act_len = payload_len + HTC_HDR_LENGTH;
1843
1844		/* validate the actual header that was refreshed  */
1845		if (packet->act_len > packet->buf_len) {
1846			ath6kl_err("refreshed hdr payload len (%d) in bundled recv is invalid (hdr: 0x%X)\n",
1847				   payload_len, lk_ahd);
1848			/*
1849			 * Limit this to max buffer just to print out some
1850			 * of the buffer.
1851			 */
1852			packet->act_len = min(packet->act_len, packet->buf_len);
1853			status = -ENOMEM;
1854			goto fail_rx;
1855		}
1856
1857		if (packet->endpoint != htc_hdr->eid) {
1858			ath6kl_err("refreshed hdr ep (%d) does not match expected ep (%d)\n",
1859				   htc_hdr->eid, packet->endpoint);
1860			status = -ENOMEM;
1861			goto fail_rx;
1862		}
1863	}
1864
1865	if (lk_ahd != packet->info.rx.exp_hdr) {
1866		ath6kl_err("%s(): lk_ahd mismatch! (pPkt:0x%p flags:0x%X)\n",
1867			   __func__, packet, packet->info.rx.rx_flags);
1868		ath6kl_dbg_dump(ATH6KL_DBG_HTC, "htc rx expected lk_ahd",
1869				"", &packet->info.rx.exp_hdr, 4);
1870		ath6kl_dbg_dump(ATH6KL_DBG_HTC, "htc rx current header",
1871				"", (u8 *)&lk_ahd, sizeof(lk_ahd));
1872		status = -ENOMEM;
1873		goto fail_rx;
1874	}
1875
1876	if (htc_hdr->flags & HTC_FLG_RX_TRAILER) {
1877		if (htc_hdr->ctrl[0] < sizeof(struct htc_record_hdr) ||
1878		    htc_hdr->ctrl[0] > payload_len) {
1879			ath6kl_err("%s(): invalid hdr (payload len should be :%d, CB[0] is:%d)\n",
1880				   __func__, payload_len, htc_hdr->ctrl[0]);
1881			status = -ENOMEM;
1882			goto fail_rx;
1883		}
1884
1885		if (packet->info.rx.rx_flags & HTC_RX_PKT_IGNORE_LOOKAHEAD) {
1886			next_lkahds = NULL;
1887			n_lkahds = NULL;
1888		}
1889
1890		status = htc_proc_trailer(target, packet->buf + HTC_HDR_LENGTH
1891					  + payload_len - htc_hdr->ctrl[0],
1892					  htc_hdr->ctrl[0], next_lkahds,
1893					   n_lkahds, packet->endpoint);
1894
1895		if (status)
1896			goto fail_rx;
1897
1898		packet->act_len -= htc_hdr->ctrl[0];
1899	}
1900
1901	packet->buf += HTC_HDR_LENGTH;
1902	packet->act_len -= HTC_HDR_LENGTH;
1903
1904fail_rx:
1905	if (status)
1906		ath6kl_dbg_dump(ATH6KL_DBG_HTC, "htc rx bad packet",
1907				"", packet->buf, packet->act_len);
1908
1909	return status;
1910}
1911
1912static void ath6kl_htc_rx_complete(struct htc_endpoint *endpoint,
1913				   struct htc_packet *packet)
1914{
1915		ath6kl_dbg(ATH6KL_DBG_HTC,
1916			   "htc rx complete ep %d packet 0x%p\n",
1917			   endpoint->eid, packet);
1918
1919		endpoint->ep_cb.rx(endpoint->target, packet);
1920}
1921
1922static int ath6kl_htc_rx_bundle(struct htc_target *target,
1923				struct list_head *rxq,
1924				struct list_head *sync_compq,
1925				int *n_pkt_fetched, bool part_bundle)
1926{
1927	struct hif_scatter_req *scat_req;
1928	struct htc_packet *packet;
1929	int rem_space = target->max_rx_bndl_sz;
1930	int n_scat_pkt, status = 0, i, len;
1931
1932	n_scat_pkt = get_queue_depth(rxq);
1933	n_scat_pkt = min(n_scat_pkt, target->msg_per_bndl_max);
1934
1935	if ((get_queue_depth(rxq) - n_scat_pkt) > 0) {
1936		/*
1937		 * We were forced to split this bundle receive operation
1938		 * all packets in this partial bundle must have their
1939		 * lookaheads ignored.
1940		 */
1941		part_bundle = true;
1942
1943		/*
1944		 * This would only happen if the target ignored our max
1945		 * bundle limit.
1946		 */
1947		ath6kl_warn("%s(): partial bundle detected num:%d , %d\n",
1948			    __func__, get_queue_depth(rxq), n_scat_pkt);
1949	}
1950
1951	len = 0;
1952
1953	ath6kl_dbg(ATH6KL_DBG_HTC,
1954		   "htc rx bundle depth %d pkts %d\n",
1955		   get_queue_depth(rxq), n_scat_pkt);
1956
1957	scat_req = hif_scatter_req_get(target->dev->ar);
1958
1959	if (scat_req == NULL)
1960		goto fail_rx_pkt;
1961
1962	for (i = 0; i < n_scat_pkt; i++) {
1963		int pad_len;
1964
1965		packet = list_first_entry(rxq, struct htc_packet, list);
1966		list_del(&packet->list);
1967
1968		pad_len = CALC_TXRX_PADDED_LEN(target,
1969						   packet->act_len);
1970
1971		if ((rem_space - pad_len) < 0) {
1972			list_add(&packet->list, rxq);
1973			break;
1974		}
1975
1976		rem_space -= pad_len;
1977
1978		if (part_bundle || (i < (n_scat_pkt - 1)))
1979			/*
1980			 * Packet 0..n-1 cannot be checked for look-aheads
1981			 * since we are fetching a bundle the last packet
1982			 * however can have it's lookahead used
1983			 */
1984			packet->info.rx.rx_flags |=
1985			    HTC_RX_PKT_IGNORE_LOOKAHEAD;
1986
1987		/* NOTE: 1 HTC packet per scatter entry */
1988		scat_req->scat_list[i].buf = packet->buf;
1989		scat_req->scat_list[i].len = pad_len;
1990
1991		packet->info.rx.rx_flags |= HTC_RX_PKT_PART_OF_BUNDLE;
1992
1993		list_add_tail(&packet->list, sync_compq);
1994
1995		WARN_ON(!scat_req->scat_list[i].len);
1996		len += scat_req->scat_list[i].len;
1997	}
1998
1999	scat_req->len = len;
2000	scat_req->scat_entries = i;
2001
2002	status = ath6kl_hif_submit_scat_req(target->dev, scat_req, true);
2003
2004	if (!status)
2005		*n_pkt_fetched = i;
2006
2007	/* free scatter request */
2008	hif_scatter_req_add(target->dev->ar, scat_req);
2009
2010fail_rx_pkt:
2011
2012	return status;
2013}
2014
2015static int ath6kl_htc_rx_process_packets(struct htc_target *target,
2016					 struct list_head *comp_pktq,
2017					 u32 lk_ahds[],
2018					 int *n_lk_ahd)
2019{
2020	struct htc_packet *packet, *tmp_pkt;
2021	struct htc_endpoint *ep;
2022	int status = 0;
2023
2024	list_for_each_entry_safe(packet, tmp_pkt, comp_pktq, list) {
2025		ep = &target->endpoint[packet->endpoint];
2026
2027		trace_ath6kl_htc_rx(packet->status, packet->endpoint,
2028				    packet->buf, packet->act_len);
2029
2030		/* process header for each of the recv packet */
2031		status = ath6kl_htc_rx_process_hdr(target, packet, lk_ahds,
2032						   n_lk_ahd);
2033		if (status)
2034			return status;
2035
2036		list_del(&packet->list);
2037
2038		if (list_empty(comp_pktq)) {
2039			/*
2040			 * Last packet's more packet flag is set
2041			 * based on the lookahead.
2042			 */
2043			if (*n_lk_ahd > 0)
2044				ath6kl_htc_rx_set_indicate(lk_ahds[0],
2045							   ep, packet);
2046		} else
2047			/*
2048			 * Packets in a bundle automatically have
2049			 * this flag set.
2050			 */
2051			packet->info.rx.indicat_flags |=
2052				HTC_RX_FLAGS_INDICATE_MORE_PKTS;
2053
2054		ath6kl_htc_rx_update_stats(ep, *n_lk_ahd);
2055
2056		if (packet->info.rx.rx_flags & HTC_RX_PKT_PART_OF_BUNDLE)
2057			ep->ep_st.rx_bundl += 1;
2058
2059		ath6kl_htc_rx_complete(ep, packet);
2060	}
2061
2062	return status;
2063}
2064
2065static int ath6kl_htc_rx_fetch(struct htc_target *target,
2066			       struct list_head *rx_pktq,
2067			       struct list_head *comp_pktq)
2068{
2069	int fetched_pkts;
2070	bool part_bundle = false;
2071	int status = 0;
2072	struct list_head tmp_rxq;
2073	struct htc_packet *packet, *tmp_pkt;
2074
2075	/* now go fetch the list of HTC packets */
2076	while (!list_empty(rx_pktq)) {
2077		fetched_pkts = 0;
2078
2079		INIT_LIST_HEAD(&tmp_rxq);
2080
2081		if (target->rx_bndl_enable && (get_queue_depth(rx_pktq) > 1)) {
2082			/*
2083			 * There are enough packets to attempt a
2084			 * bundle transfer and recv bundling is
2085			 * allowed.
2086			 */
2087			status = ath6kl_htc_rx_bundle(target, rx_pktq,
2088						      &tmp_rxq,
2089						      &fetched_pkts,
2090						      part_bundle);
2091			if (status)
2092				goto fail_rx;
2093
2094			if (!list_empty(rx_pktq))
2095				part_bundle = true;
2096
2097			list_splice_tail_init(&tmp_rxq, comp_pktq);
2098		}
2099
2100		if (!fetched_pkts) {
2101
2102			packet = list_first_entry(rx_pktq, struct htc_packet,
2103						   list);
2104
2105			/* fully synchronous */
2106			packet->completion = NULL;
2107
2108			if (!list_is_singular(rx_pktq))
2109				/*
2110				 * look_aheads in all packet
2111				 * except the last one in the
2112				 * bundle must be ignored
2113				 */
2114				packet->info.rx.rx_flags |=
2115					HTC_RX_PKT_IGNORE_LOOKAHEAD;
2116
2117			/* go fetch the packet */
2118			status = ath6kl_htc_rx_packet(target, packet,
2119						      packet->act_len);
2120
2121			list_move_tail(&packet->list, &tmp_rxq);
2122
2123			if (status)
2124				goto fail_rx;
2125
2126			list_splice_tail_init(&tmp_rxq, comp_pktq);
2127		}
2128	}
2129
2130	return 0;
2131
2132fail_rx:
2133
2134	/*
2135	 * Cleanup any packets we allocated but didn't use to
2136	 * actually fetch any packets.
2137	 */
2138
2139	list_for_each_entry_safe(packet, tmp_pkt, rx_pktq, list) {
2140		list_del(&packet->list);
2141		htc_reclaim_rxbuf(target, packet,
2142				  &target->endpoint[packet->endpoint]);
2143	}
2144
2145	list_for_each_entry_safe(packet, tmp_pkt, &tmp_rxq, list) {
2146		list_del(&packet->list);
2147		htc_reclaim_rxbuf(target, packet,
2148				  &target->endpoint[packet->endpoint]);
2149	}
2150
2151	return status;
2152}
2153
2154int ath6kl_htc_rxmsg_pending_handler(struct htc_target *target,
2155				     u32 msg_look_ahead, int *num_pkts)
2156{
2157	struct htc_packet *packets, *tmp_pkt;
2158	struct htc_endpoint *endpoint;
2159	struct list_head rx_pktq, comp_pktq;
2160	int status = 0;
2161	u32 look_aheads[HTC_HOST_MAX_MSG_PER_BUNDLE];
2162	int num_look_ahead = 1;
2163	enum htc_endpoint_id id;
2164	int n_fetched = 0;
2165
2166	INIT_LIST_HEAD(&comp_pktq);
2167	*num_pkts = 0;
2168
2169	/*
2170	 * On first entry copy the look_aheads into our temp array for
2171	 * processing
2172	 */
2173	look_aheads[0] = msg_look_ahead;
2174
2175	while (true) {
2176
2177		/*
2178		 * First lookahead sets the expected endpoint IDs for all
2179		 * packets in a bundle.
2180		 */
2181		id = ((struct htc_frame_hdr *)&look_aheads[0])->eid;
2182		endpoint = &target->endpoint[id];
2183
2184		if (id >= ENDPOINT_MAX) {
2185			ath6kl_err("MsgPend, invalid endpoint in look-ahead: %d\n",
2186				   id);
2187			status = -ENOMEM;
2188			break;
2189		}
2190
2191		INIT_LIST_HEAD(&rx_pktq);
2192		INIT_LIST_HEAD(&comp_pktq);
2193
2194		/*
2195		 * Try to allocate as many HTC RX packets indicated by the
2196		 * look_aheads.
2197		 */
2198		status = ath6kl_htc_rx_alloc(target, look_aheads,
2199					     num_look_ahead, endpoint,
2200					     &rx_pktq);
2201		if (status)
2202			break;
2203
2204		if (get_queue_depth(&rx_pktq) >= 2)
2205			/*
2206			 * A recv bundle was detected, force IRQ status
2207			 * re-check again
2208			 */
2209			target->chk_irq_status_cnt = 1;
2210
2211		n_fetched += get_queue_depth(&rx_pktq);
2212
2213		num_look_ahead = 0;
2214
2215		status = ath6kl_htc_rx_fetch(target, &rx_pktq, &comp_pktq);
2216
2217		if (!status)
2218			ath6kl_htc_rx_chk_water_mark(endpoint);
2219
2220		/* Process fetched packets */
2221		status = ath6kl_htc_rx_process_packets(target, &comp_pktq,
2222						       look_aheads,
2223						       &num_look_ahead);
2224
2225		if (!num_look_ahead || status)
2226			break;
2227
2228		/*
2229		 * For SYNCH processing, if we get here, we are running
2230		 * through the loop again due to a detected lookahead. Set
2231		 * flag that we should re-check IRQ status registers again
2232		 * before leaving IRQ processing, this can net better
2233		 * performance in high throughput situations.
2234		 */
2235		target->chk_irq_status_cnt = 1;
2236	}
2237
2238	if (status) {
2239		ath6kl_err("failed to get pending recv messages: %d\n",
2240			   status);
 
2241
2242		/* cleanup any packets in sync completion queue */
2243		list_for_each_entry_safe(packets, tmp_pkt, &comp_pktq, list) {
2244			list_del(&packets->list);
2245			htc_reclaim_rxbuf(target, packets,
2246					  &target->endpoint[packets->endpoint]);
2247		}
2248
2249		if (target->htc_flags & HTC_OP_STATE_STOPPING) {
2250			ath6kl_warn("host is going to stop blocking receiver for htc_stop\n");
2251			ath6kl_hif_rx_control(target->dev, false);
2252		}
2253	}
2254
2255	/*
2256	 * Before leaving, check to see if host ran out of buffers and
2257	 * needs to stop the receiver.
2258	 */
2259	if (target->rx_st_flags & HTC_RECV_WAIT_BUFFERS) {
2260		ath6kl_warn("host has no rx buffers blocking receiver to prevent overrun\n");
2261		ath6kl_hif_rx_control(target->dev, false);
2262	}
2263	*num_pkts = n_fetched;
2264
2265	return status;
2266}
2267
2268/*
2269 * Synchronously wait for a control message from the target,
2270 * This function is used at initialization time ONLY.  At init messages
2271 * on ENDPOINT 0 are expected.
2272 */
2273static struct htc_packet *htc_wait_for_ctrl_msg(struct htc_target *target)
2274{
2275	struct htc_packet *packet = NULL;
2276	struct htc_frame_hdr *htc_hdr;
2277	u32 look_ahead;
2278
2279	if (ath6kl_hif_poll_mboxmsg_rx(target->dev, &look_ahead,
2280				       HTC_TARGET_RESPONSE_TIMEOUT))
2281		return NULL;
2282
2283	ath6kl_dbg(ATH6KL_DBG_HTC,
2284		   "htc rx wait ctrl look_ahead 0x%X\n", look_ahead);
2285
2286	htc_hdr = (struct htc_frame_hdr *)&look_ahead;
2287
2288	if (htc_hdr->eid != ENDPOINT_0)
2289		return NULL;
2290
2291	packet = htc_get_control_buf(target, false);
2292
2293	if (!packet)
2294		return NULL;
2295
2296	packet->info.rx.rx_flags = 0;
2297	packet->info.rx.exp_hdr = look_ahead;
2298	packet->act_len = le16_to_cpu(htc_hdr->payld_len) + HTC_HDR_LENGTH;
2299
2300	if (packet->act_len > packet->buf_len)
2301		goto fail_ctrl_rx;
2302
2303	/* we want synchronous operation */
2304	packet->completion = NULL;
2305
2306	/* get the message from the device, this will block */
2307	if (ath6kl_htc_rx_packet(target, packet, packet->act_len))
2308		goto fail_ctrl_rx;
2309
2310	trace_ath6kl_htc_rx(packet->status, packet->endpoint,
2311			    packet->buf, packet->act_len);
2312
2313	/* process receive header */
2314	packet->status = ath6kl_htc_rx_process_hdr(target, packet, NULL, NULL);
2315
2316	if (packet->status) {
2317		ath6kl_err("htc_wait_for_ctrl_msg, ath6kl_htc_rx_process_hdr failed (status = %d)\n",
2318			   packet->status);
2319		goto fail_ctrl_rx;
2320	}
2321
2322	return packet;
2323
2324fail_ctrl_rx:
2325	if (packet != NULL) {
2326		htc_rxpkt_reset(packet);
2327		reclaim_rx_ctrl_buf(target, packet);
2328	}
2329
2330	return NULL;
2331}
2332
2333static int ath6kl_htc_mbox_add_rxbuf_multiple(struct htc_target *target,
2334				  struct list_head *pkt_queue)
2335{
2336	struct htc_endpoint *endpoint;
2337	struct htc_packet *first_pkt;
2338	bool rx_unblock = false;
2339	int status = 0, depth;
2340
2341	if (list_empty(pkt_queue))
2342		return -ENOMEM;
2343
2344	first_pkt = list_first_entry(pkt_queue, struct htc_packet, list);
2345
2346	if (first_pkt->endpoint >= ENDPOINT_MAX)
2347		return status;
2348
2349	depth = get_queue_depth(pkt_queue);
2350
2351	ath6kl_dbg(ATH6KL_DBG_HTC,
2352		   "htc rx add multiple ep id %d cnt %d len %d\n",
2353		first_pkt->endpoint, depth, first_pkt->buf_len);
2354
2355	endpoint = &target->endpoint[first_pkt->endpoint];
2356
2357	if (target->htc_flags & HTC_OP_STATE_STOPPING) {
2358		struct htc_packet *packet, *tmp_pkt;
2359
2360		/* walk through queue and mark each one canceled */
2361		list_for_each_entry_safe(packet, tmp_pkt, pkt_queue, list) {
2362			packet->status = -ECANCELED;
2363			list_del(&packet->list);
2364			ath6kl_htc_rx_complete(endpoint, packet);
2365		}
2366
2367		return status;
2368	}
2369
2370	spin_lock_bh(&target->rx_lock);
2371
2372	list_splice_tail_init(pkt_queue, &endpoint->rx_bufq);
2373
2374	/* check if we are blocked waiting for a new buffer */
2375	if (target->rx_st_flags & HTC_RECV_WAIT_BUFFERS) {
2376		if (target->ep_waiting == first_pkt->endpoint) {
2377			ath6kl_dbg(ATH6KL_DBG_HTC,
2378				   "htc rx blocked on ep %d, unblocking\n",
2379				   target->ep_waiting);
2380			target->rx_st_flags &= ~HTC_RECV_WAIT_BUFFERS;
2381			target->ep_waiting = ENDPOINT_MAX;
2382			rx_unblock = true;
2383		}
2384	}
2385
2386	spin_unlock_bh(&target->rx_lock);
2387
2388	if (rx_unblock && !(target->htc_flags & HTC_OP_STATE_STOPPING))
2389		/* TODO : implement a buffer threshold count? */
2390		ath6kl_hif_rx_control(target->dev, true);
2391
2392	return status;
2393}
2394
2395static void ath6kl_htc_mbox_flush_rx_buf(struct htc_target *target)
2396{
2397	struct htc_endpoint *endpoint;
2398	struct htc_packet *packet, *tmp_pkt;
2399	int i;
2400
2401	for (i = ENDPOINT_0; i < ENDPOINT_MAX; i++) {
2402		endpoint = &target->endpoint[i];
2403		if (!endpoint->svc_id)
2404			/* not in use.. */
2405			continue;
2406
2407		spin_lock_bh(&target->rx_lock);
2408		list_for_each_entry_safe(packet, tmp_pkt,
2409					 &endpoint->rx_bufq, list) {
2410			list_del(&packet->list);
2411			spin_unlock_bh(&target->rx_lock);
2412			ath6kl_dbg(ATH6KL_DBG_HTC,
2413				   "htc rx flush pkt 0x%p  len %d  ep %d\n",
2414				   packet, packet->buf_len,
2415				   packet->endpoint);
2416			/*
2417			 * packets in rx_bufq of endpoint 0 have originally
2418			 * been queued from target->free_ctrl_rxbuf where
2419			 * packet and packet->buf_start are allocated
2420			 * separately using kmalloc(). For other endpoint
2421			 * rx_bufq, it is allocated as skb where packet is
2422			 * skb->head. Take care of this difference while freeing
2423			 * the memory.
2424			 */
2425			if (packet->endpoint == ENDPOINT_0) {
2426				kfree(packet->buf_start);
2427				kfree(packet);
2428			} else {
2429				dev_kfree_skb(packet->pkt_cntxt);
2430			}
2431			spin_lock_bh(&target->rx_lock);
2432		}
2433		spin_unlock_bh(&target->rx_lock);
2434	}
2435}
2436
2437static int ath6kl_htc_mbox_conn_service(struct htc_target *target,
2438			    struct htc_service_connect_req *conn_req,
2439			    struct htc_service_connect_resp *conn_resp)
2440{
2441	struct htc_packet *rx_pkt = NULL;
2442	struct htc_packet *tx_pkt = NULL;
2443	struct htc_conn_service_resp *resp_msg;
2444	struct htc_conn_service_msg *conn_msg;
2445	struct htc_endpoint *endpoint;
2446	enum htc_endpoint_id assigned_ep = ENDPOINT_MAX;
2447	unsigned int max_msg_sz = 0;
2448	int status = 0;
2449	u16 msg_id;
2450
2451	ath6kl_dbg(ATH6KL_DBG_HTC,
2452		   "htc connect service target 0x%p service id 0x%x\n",
2453		   target, conn_req->svc_id);
2454
2455	if (conn_req->svc_id == HTC_CTRL_RSVD_SVC) {
2456		/* special case for pseudo control service */
2457		assigned_ep = ENDPOINT_0;
2458		max_msg_sz = HTC_MAX_CTRL_MSG_LEN;
2459	} else {
2460		/* allocate a packet to send to the target */
2461		tx_pkt = htc_get_control_buf(target, true);
2462
2463		if (!tx_pkt)
2464			return -ENOMEM;
2465
2466		conn_msg = (struct htc_conn_service_msg *)tx_pkt->buf;
2467		memset(conn_msg, 0, sizeof(*conn_msg));
2468		conn_msg->msg_id = cpu_to_le16(HTC_MSG_CONN_SVC_ID);
2469		conn_msg->svc_id = cpu_to_le16(conn_req->svc_id);
2470		conn_msg->conn_flags = cpu_to_le16(conn_req->conn_flags);
2471
2472		set_htc_pkt_info(tx_pkt, NULL, (u8 *) conn_msg,
2473				 sizeof(*conn_msg) + conn_msg->svc_meta_len,
2474				 ENDPOINT_0, HTC_SERVICE_TX_PACKET_TAG);
2475
2476		/* we want synchronous operation */
2477		tx_pkt->completion = NULL;
2478		ath6kl_htc_tx_prep_pkt(tx_pkt, 0, 0, 0);
2479		status = ath6kl_htc_tx_issue(target, tx_pkt);
2480
2481		if (status)
2482			goto fail_tx;
2483
2484		/* wait for response */
2485		rx_pkt = htc_wait_for_ctrl_msg(target);
2486
2487		if (!rx_pkt) {
2488			status = -ENOMEM;
2489			goto fail_tx;
2490		}
2491
2492		resp_msg = (struct htc_conn_service_resp *)rx_pkt->buf;
2493		msg_id = le16_to_cpu(resp_msg->msg_id);
2494
2495		if ((msg_id != HTC_MSG_CONN_SVC_RESP_ID) ||
2496		    (rx_pkt->act_len < sizeof(*resp_msg))) {
2497			status = -ENOMEM;
2498			goto fail_tx;
2499		}
2500
2501		conn_resp->resp_code = resp_msg->status;
2502		/* check response status */
2503		if (resp_msg->status != HTC_SERVICE_SUCCESS) {
2504			ath6kl_err("target failed service 0x%X connect request (status:%d)\n",
2505				   resp_msg->svc_id, resp_msg->status);
2506			status = -ENOMEM;
2507			goto fail_tx;
2508		}
2509
2510		assigned_ep = (enum htc_endpoint_id)resp_msg->eid;
2511		max_msg_sz = le16_to_cpu(resp_msg->max_msg_sz);
2512	}
2513
2514	if (WARN_ON_ONCE(assigned_ep == ENDPOINT_UNUSED ||
2515			 assigned_ep >= ENDPOINT_MAX || !max_msg_sz)) {
2516		status = -ENOMEM;
2517		goto fail_tx;
2518	}
2519
2520	endpoint = &target->endpoint[assigned_ep];
2521	endpoint->eid = assigned_ep;
2522	if (endpoint->svc_id) {
2523		status = -ENOMEM;
2524		goto fail_tx;
2525	}
2526
2527	/* return assigned endpoint to caller */
2528	conn_resp->endpoint = assigned_ep;
2529	conn_resp->len_max = max_msg_sz;
2530
2531	/* setup the endpoint */
2532
2533	/* this marks the endpoint in use */
2534	endpoint->svc_id = conn_req->svc_id;
2535
2536	endpoint->max_txq_depth = conn_req->max_txq_depth;
2537	endpoint->len_max = max_msg_sz;
2538	endpoint->ep_cb = conn_req->ep_cb;
2539	endpoint->cred_dist.svc_id = conn_req->svc_id;
2540	endpoint->cred_dist.htc_ep = endpoint;
2541	endpoint->cred_dist.endpoint = assigned_ep;
2542	endpoint->cred_dist.cred_sz = target->tgt_cred_sz;
2543
2544	switch (endpoint->svc_id) {
2545	case WMI_DATA_BK_SVC:
2546		endpoint->tx_drop_packet_threshold = MAX_DEF_COOKIE_NUM / 3;
2547		break;
2548	default:
2549		endpoint->tx_drop_packet_threshold = MAX_HI_COOKIE_NUM;
2550		break;
2551	}
2552
2553	if (conn_req->max_rxmsg_sz) {
2554		/*
2555		 * Override cred_per_msg calculation, this optimizes
2556		 * the credit-low indications since the host will actually
2557		 * issue smaller messages in the Send path.
2558		 */
2559		if (conn_req->max_rxmsg_sz > max_msg_sz) {
2560			status = -ENOMEM;
2561			goto fail_tx;
2562		}
2563		endpoint->cred_dist.cred_per_msg =
2564		    conn_req->max_rxmsg_sz / target->tgt_cred_sz;
2565	} else
2566		endpoint->cred_dist.cred_per_msg =
2567		    max_msg_sz / target->tgt_cred_sz;
2568
2569	if (!endpoint->cred_dist.cred_per_msg)
2570		endpoint->cred_dist.cred_per_msg = 1;
2571
2572	/* save local connection flags */
2573	endpoint->conn_flags = conn_req->flags;
2574
2575fail_tx:
2576	if (tx_pkt)
2577		htc_reclaim_txctrl_buf(target, tx_pkt);
2578
2579	if (rx_pkt) {
2580		htc_rxpkt_reset(rx_pkt);
2581		reclaim_rx_ctrl_buf(target, rx_pkt);
2582	}
2583
2584	return status;
2585}
2586
2587static void reset_ep_state(struct htc_target *target)
2588{
2589	struct htc_endpoint *endpoint;
2590	int i;
2591
2592	for (i = ENDPOINT_0; i < ENDPOINT_MAX; i++) {
2593		endpoint = &target->endpoint[i];
2594		memset(&endpoint->cred_dist, 0, sizeof(endpoint->cred_dist));
2595		endpoint->svc_id = 0;
2596		endpoint->len_max = 0;
2597		endpoint->max_txq_depth = 0;
2598		memset(&endpoint->ep_st, 0,
2599		       sizeof(endpoint->ep_st));
2600		INIT_LIST_HEAD(&endpoint->rx_bufq);
2601		INIT_LIST_HEAD(&endpoint->txq);
2602		endpoint->target = target;
2603	}
2604
2605	/* reset distribution list */
2606	/* FIXME: free existing entries */
2607	INIT_LIST_HEAD(&target->cred_dist_list);
2608}
2609
2610static int ath6kl_htc_mbox_get_rxbuf_num(struct htc_target *target,
2611			     enum htc_endpoint_id endpoint)
2612{
2613	int num;
2614
2615	spin_lock_bh(&target->rx_lock);
2616	num = get_queue_depth(&(target->endpoint[endpoint].rx_bufq));
2617	spin_unlock_bh(&target->rx_lock);
2618	return num;
2619}
2620
2621static void htc_setup_msg_bndl(struct htc_target *target)
2622{
2623	/* limit what HTC can handle */
2624	target->msg_per_bndl_max = min(HTC_HOST_MAX_MSG_PER_BUNDLE,
2625				       target->msg_per_bndl_max);
2626
2627	if (ath6kl_hif_enable_scatter(target->dev->ar)) {
2628		target->msg_per_bndl_max = 0;
2629		return;
2630	}
2631
2632	/* limit bundle what the device layer can handle */
2633	target->msg_per_bndl_max = min(target->max_scat_entries,
2634				       target->msg_per_bndl_max);
2635
2636	ath6kl_dbg(ATH6KL_DBG_BOOT,
2637		   "htc bundling allowed msg_per_bndl_max %d\n",
2638		   target->msg_per_bndl_max);
2639
2640	/* Max rx bundle size is limited by the max tx bundle size */
2641	target->max_rx_bndl_sz = target->max_xfer_szper_scatreq;
2642	/* Max tx bundle size if limited by the extended mbox address range */
2643	target->max_tx_bndl_sz = min(HIF_MBOX0_EXT_WIDTH,
2644				     target->max_xfer_szper_scatreq);
2645
2646	ath6kl_dbg(ATH6KL_DBG_BOOT, "htc max_rx_bndl_sz %d max_tx_bndl_sz %d\n",
2647		   target->max_rx_bndl_sz, target->max_tx_bndl_sz);
2648
2649	if (target->max_tx_bndl_sz)
2650		/* tx_bndl_mask is enabled per AC, each has 1 bit */
2651		target->tx_bndl_mask = (1 << WMM_NUM_AC) - 1;
2652
2653	if (target->max_rx_bndl_sz)
2654		target->rx_bndl_enable = true;
2655
2656	if ((target->tgt_cred_sz % target->block_sz) != 0) {
2657		ath6kl_warn("credit size: %d is not block aligned! Disabling send bundling\n",
2658			    target->tgt_cred_sz);
2659
2660		/*
2661		 * Disallow send bundling since the credit size is
2662		 * not aligned to a block size the I/O block
2663		 * padding will spill into the next credit buffer
2664		 * which is fatal.
2665		 */
2666		target->tx_bndl_mask = 0;
2667	}
2668}
2669
2670static int ath6kl_htc_mbox_wait_target(struct htc_target *target)
2671{
2672	struct htc_packet *packet = NULL;
2673	struct htc_ready_ext_msg *rdy_msg;
2674	struct htc_service_connect_req connect;
2675	struct htc_service_connect_resp resp;
2676	int status;
2677
2678	/* we should be getting 1 control message that the target is ready */
2679	packet = htc_wait_for_ctrl_msg(target);
2680
2681	if (!packet)
2682		return -ENOMEM;
2683
2684	/* we controlled the buffer creation so it's properly aligned */
2685	rdy_msg = (struct htc_ready_ext_msg *)packet->buf;
2686
2687	if ((le16_to_cpu(rdy_msg->ver2_0_info.msg_id) != HTC_MSG_READY_ID) ||
2688	    (packet->act_len < sizeof(struct htc_ready_msg))) {
2689		status = -ENOMEM;
2690		goto fail_wait_target;
2691	}
2692
2693	if (!rdy_msg->ver2_0_info.cred_cnt || !rdy_msg->ver2_0_info.cred_sz) {
2694		status = -ENOMEM;
2695		goto fail_wait_target;
2696	}
2697
2698	target->tgt_creds = le16_to_cpu(rdy_msg->ver2_0_info.cred_cnt);
2699	target->tgt_cred_sz = le16_to_cpu(rdy_msg->ver2_0_info.cred_sz);
2700
2701	ath6kl_dbg(ATH6KL_DBG_BOOT,
2702		   "htc target ready credits %d size %d\n",
2703		   target->tgt_creds, target->tgt_cred_sz);
2704
2705	/* check if this is an extended ready message */
2706	if (packet->act_len >= sizeof(struct htc_ready_ext_msg)) {
2707		/* this is an extended message */
2708		target->htc_tgt_ver = rdy_msg->htc_ver;
2709		target->msg_per_bndl_max = rdy_msg->msg_per_htc_bndl;
2710	} else {
2711		/* legacy */
2712		target->htc_tgt_ver = HTC_VERSION_2P0;
2713		target->msg_per_bndl_max = 0;
2714	}
2715
2716	ath6kl_dbg(ATH6KL_DBG_BOOT, "htc using protocol %s (%d)\n",
2717		   (target->htc_tgt_ver == HTC_VERSION_2P0) ? "2.0" : ">= 2.1",
2718		   target->htc_tgt_ver);
2719
2720	if (target->msg_per_bndl_max > 0)
2721		htc_setup_msg_bndl(target);
2722
2723	/* setup our pseudo HTC control endpoint connection */
2724	memset(&connect, 0, sizeof(connect));
2725	memset(&resp, 0, sizeof(resp));
2726	connect.ep_cb.rx = htc_ctrl_rx;
2727	connect.ep_cb.rx_refill = NULL;
2728	connect.ep_cb.tx_full = NULL;
2729	connect.max_txq_depth = NUM_CONTROL_BUFFERS;
2730	connect.svc_id = HTC_CTRL_RSVD_SVC;
2731
2732	/* connect fake service */
2733	status = ath6kl_htc_mbox_conn_service((void *)target, &connect, &resp);
2734
2735	if (status)
2736		/*
2737		 * FIXME: this call doesn't make sense, the caller should
2738		 * call ath6kl_htc_mbox_cleanup() when it wants remove htc
2739		 */
2740		ath6kl_hif_cleanup_scatter(target->dev->ar);
2741
2742fail_wait_target:
2743	if (packet) {
2744		htc_rxpkt_reset(packet);
2745		reclaim_rx_ctrl_buf(target, packet);
2746	}
2747
2748	return status;
2749}
2750
2751/*
2752 * Start HTC, enable interrupts and let the target know
2753 * host has finished setup.
2754 */
2755static int ath6kl_htc_mbox_start(struct htc_target *target)
2756{
2757	struct htc_packet *packet;
2758	int status;
2759
2760	memset(&target->dev->irq_proc_reg, 0,
2761	       sizeof(target->dev->irq_proc_reg));
2762
2763	/* Disable interrupts at the chip level */
2764	ath6kl_hif_disable_intrs(target->dev);
2765
2766	target->htc_flags = 0;
2767	target->rx_st_flags = 0;
2768
2769	/* Push control receive buffers into htc control endpoint */
2770	while ((packet = htc_get_control_buf(target, false)) != NULL) {
2771		status = htc_add_rxbuf(target, packet);
2772		if (status)
2773			return status;
2774	}
2775
2776	/* NOTE: the first entry in the distribution list is ENDPOINT_0 */
2777	ath6kl_credit_init(target->credit_info, &target->cred_dist_list,
2778			   target->tgt_creds);
2779
2780	dump_cred_dist_stats(target);
2781
2782	/* Indicate to the target of the setup completion */
2783	status = htc_setup_tx_complete(target);
2784
2785	if (status)
2786		return status;
2787
2788	/* unmask interrupts */
2789	status = ath6kl_hif_unmask_intrs(target->dev);
2790
2791	if (status)
2792		ath6kl_htc_mbox_stop(target);
2793
2794	return status;
2795}
2796
2797static int ath6kl_htc_reset(struct htc_target *target)
2798{
2799	u32 block_size, ctrl_bufsz;
2800	struct htc_packet *packet;
2801	int i;
2802
2803	reset_ep_state(target);
2804
2805	block_size = target->dev->ar->mbox_info.block_size;
2806
2807	ctrl_bufsz = (block_size > HTC_MAX_CTRL_MSG_LEN) ?
2808		      (block_size + HTC_HDR_LENGTH) :
2809		      (HTC_MAX_CTRL_MSG_LEN + HTC_HDR_LENGTH);
2810
2811	for (i = 0; i < NUM_CONTROL_BUFFERS; i++) {
2812		packet = kzalloc(sizeof(*packet), GFP_KERNEL);
2813		if (!packet)
2814			return -ENOMEM;
2815
2816		packet->buf_start = kzalloc(ctrl_bufsz, GFP_KERNEL);
2817		if (!packet->buf_start) {
2818			kfree(packet);
2819			return -ENOMEM;
2820		}
2821
2822		packet->buf_len = ctrl_bufsz;
2823		if (i < NUM_CONTROL_RX_BUFFERS) {
2824			packet->act_len = 0;
2825			packet->buf = packet->buf_start;
2826			packet->endpoint = ENDPOINT_0;
2827			list_add_tail(&packet->list, &target->free_ctrl_rxbuf);
2828		} else
2829			list_add_tail(&packet->list, &target->free_ctrl_txbuf);
 
2830	}
2831
2832	return 0;
2833}
2834
2835/* htc_stop: stop interrupt reception, and flush all queued buffers */
2836static void ath6kl_htc_mbox_stop(struct htc_target *target)
2837{
2838	spin_lock_bh(&target->htc_lock);
2839	target->htc_flags |= HTC_OP_STATE_STOPPING;
2840	spin_unlock_bh(&target->htc_lock);
2841
2842	/*
2843	 * Masking interrupts is a synchronous operation, when this
2844	 * function returns all pending HIF I/O has completed, we can
2845	 * safely flush the queues.
2846	 */
2847	ath6kl_hif_mask_intrs(target->dev);
2848
2849	ath6kl_htc_flush_txep_all(target);
2850
2851	ath6kl_htc_mbox_flush_rx_buf(target);
2852
2853	ath6kl_htc_reset(target);
2854}
2855
2856static void *ath6kl_htc_mbox_create(struct ath6kl *ar)
2857{
2858	struct htc_target *target = NULL;
2859	int status = 0;
2860
2861	target = kzalloc(sizeof(*target), GFP_KERNEL);
2862	if (!target) {
2863		ath6kl_err("unable to allocate memory\n");
2864		return NULL;
2865	}
2866
2867	target->dev = kzalloc(sizeof(*target->dev), GFP_KERNEL);
2868	if (!target->dev) {
2869		ath6kl_err("unable to allocate memory\n");
2870		status = -ENOMEM;
2871		goto err_htc_cleanup;
2872	}
2873
2874	spin_lock_init(&target->htc_lock);
2875	spin_lock_init(&target->rx_lock);
2876	spin_lock_init(&target->tx_lock);
2877
2878	INIT_LIST_HEAD(&target->free_ctrl_txbuf);
2879	INIT_LIST_HEAD(&target->free_ctrl_rxbuf);
2880	INIT_LIST_HEAD(&target->cred_dist_list);
2881
2882	target->dev->ar = ar;
2883	target->dev->htc_cnxt = target;
2884	target->ep_waiting = ENDPOINT_MAX;
2885
2886	status = ath6kl_hif_setup(target->dev);
2887	if (status)
2888		goto err_htc_cleanup;
2889
2890	status = ath6kl_htc_reset(target);
2891	if (status)
2892		goto err_htc_cleanup;
2893
2894	return target;
2895
2896err_htc_cleanup:
2897	ath6kl_htc_mbox_cleanup(target);
2898
2899	return NULL;
2900}
2901
2902/* cleanup the HTC instance */
2903static void ath6kl_htc_mbox_cleanup(struct htc_target *target)
2904{
2905	struct htc_packet *packet, *tmp_packet;
2906
2907	ath6kl_hif_cleanup_scatter(target->dev->ar);
2908
2909	list_for_each_entry_safe(packet, tmp_packet,
2910				 &target->free_ctrl_txbuf, list) {
2911		list_del(&packet->list);
2912		kfree(packet->buf_start);
2913		kfree(packet);
2914	}
2915
2916	list_for_each_entry_safe(packet, tmp_packet,
2917				 &target->free_ctrl_rxbuf, list) {
2918		list_del(&packet->list);
2919		kfree(packet->buf_start);
2920		kfree(packet);
2921	}
2922
2923	kfree(target->dev);
2924	kfree(target);
2925}
2926
2927static const struct ath6kl_htc_ops ath6kl_htc_mbox_ops = {
2928	.create = ath6kl_htc_mbox_create,
2929	.wait_target = ath6kl_htc_mbox_wait_target,
2930	.start = ath6kl_htc_mbox_start,
2931	.conn_service = ath6kl_htc_mbox_conn_service,
2932	.tx = ath6kl_htc_mbox_tx,
2933	.stop = ath6kl_htc_mbox_stop,
2934	.cleanup = ath6kl_htc_mbox_cleanup,
2935	.flush_txep = ath6kl_htc_mbox_flush_txep,
2936	.flush_rx_buf = ath6kl_htc_mbox_flush_rx_buf,
2937	.activity_changed = ath6kl_htc_mbox_activity_changed,
2938	.get_rxbuf_num = ath6kl_htc_mbox_get_rxbuf_num,
2939	.add_rxbuf_multiple = ath6kl_htc_mbox_add_rxbuf_multiple,
2940	.credit_setup = ath6kl_htc_mbox_credit_setup,
2941};
2942
2943void ath6kl_htc_mbox_attach(struct ath6kl *ar)
2944{
2945	ar->htc_ops = &ath6kl_htc_mbox_ops;
2946}