1 /*
2  * Copyright (c) 2007-2011 Atheros Communications Inc.
3  *
4  * Permission to use, copy, modify, and/or distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include "core.h"
18 #include "hif.h"
19 #include "debug.h"
20 #include "hif-ops.h"
21 #include <asm/unaligned.h>
22 
23 #define CALC_TXRX_PADDED_LEN(dev, len)  (__ALIGN_MASK((len), (dev)->block_mask))
24 
25 /* Functions for Tx credit handling */
ath6kl_credit_deposit(struct ath6kl_htc_credit_info * cred_info,struct htc_endpoint_credit_dist * ep_dist,int credits)26 static void ath6kl_credit_deposit(struct ath6kl_htc_credit_info *cred_info,
27 				  struct htc_endpoint_credit_dist *ep_dist,
28 				  int credits)
29 {
30 	ath6kl_dbg(ATH6KL_DBG_CREDIT, "credit deposit ep %d credits %d\n",
31 		   ep_dist->endpoint, credits);
32 
33 	ep_dist->credits += credits;
34 	ep_dist->cred_assngd += credits;
35 	cred_info->cur_free_credits -= credits;
36 }
37 
ath6kl_credit_init(struct ath6kl_htc_credit_info * cred_info,struct list_head * ep_list,int tot_credits)38 static void ath6kl_credit_init(struct ath6kl_htc_credit_info *cred_info,
39 			       struct list_head *ep_list,
40 			       int tot_credits)
41 {
42 	struct htc_endpoint_credit_dist *cur_ep_dist;
43 	int count;
44 
45 	ath6kl_dbg(ATH6KL_DBG_CREDIT, "credit init total %d\n", tot_credits);
46 
47 	cred_info->cur_free_credits = tot_credits;
48 	cred_info->total_avail_credits = tot_credits;
49 
50 	list_for_each_entry(cur_ep_dist, ep_list, list) {
51 		if (cur_ep_dist->endpoint == ENDPOINT_0)
52 			continue;
53 
54 		cur_ep_dist->cred_min = cur_ep_dist->cred_per_msg;
55 
56 		if (tot_credits > 4) {
57 			if ((cur_ep_dist->svc_id == WMI_DATA_BK_SVC) ||
58 			    (cur_ep_dist->svc_id == WMI_DATA_BE_SVC)) {
59 				ath6kl_credit_deposit(cred_info,
60 						      cur_ep_dist,
61 						      cur_ep_dist->cred_min);
62 				cur_ep_dist->dist_flags |= HTC_EP_ACTIVE;
63 			}
64 		}
65 
66 		if (cur_ep_dist->svc_id == WMI_CONTROL_SVC) {
67 			ath6kl_credit_deposit(cred_info, cur_ep_dist,
68 					      cur_ep_dist->cred_min);
69 			/*
70 			 * Control service is always marked active, it
71 			 * never goes inactive EVER.
72 			 */
73 			cur_ep_dist->dist_flags |= HTC_EP_ACTIVE;
74 		} else if (cur_ep_dist->svc_id == WMI_DATA_BK_SVC)
75 			/* this is the lowest priority data endpoint */
76 			/* FIXME: this looks fishy, check */
77 			cred_info->lowestpri_ep_dist = cur_ep_dist->list;
78 
79 		/*
80 		 * Streams have to be created (explicit | implicit) for all
81 		 * kinds of traffic. BE endpoints are also inactive in the
82 		 * beginning. When BE traffic starts it creates implicit
83 		 * streams that redistributes credits.
84 		 *
85 		 * Note: all other endpoints have minimums set but are
86 		 * initially given NO credits. credits will be distributed
87 		 * as traffic activity demands
88 		 */
89 	}
90 
91 	WARN_ON(cred_info->cur_free_credits <= 0);
92 
93 	list_for_each_entry(cur_ep_dist, ep_list, list) {
94 		if (cur_ep_dist->endpoint == ENDPOINT_0)
95 			continue;
96 
97 		if (cur_ep_dist->svc_id == WMI_CONTROL_SVC)
98 			cur_ep_dist->cred_norm = cur_ep_dist->cred_per_msg;
99 		else {
100 			/*
101 			 * For the remaining data endpoints, we assume that
102 			 * each cred_per_msg are the same. We use a simple
103 			 * calculation here, we take the remaining credits
104 			 * and determine how many max messages this can
105 			 * cover and then set each endpoint's normal value
106 			 * equal to 3/4 this amount.
107 			 */
108 			count = (cred_info->cur_free_credits /
109 				 cur_ep_dist->cred_per_msg)
110 				* cur_ep_dist->cred_per_msg;
111 			count = (count * 3) >> 2;
112 			count = max(count, cur_ep_dist->cred_per_msg);
113 			cur_ep_dist->cred_norm = count;
114 
115 		}
116 
117 		ath6kl_dbg(ATH6KL_DBG_CREDIT,
118 			   "credit ep %d svc_id %d credits %d per_msg %d norm %d min %d\n",
119 			   cur_ep_dist->endpoint,
120 			   cur_ep_dist->svc_id,
121 			   cur_ep_dist->credits,
122 			   cur_ep_dist->cred_per_msg,
123 			   cur_ep_dist->cred_norm,
124 			   cur_ep_dist->cred_min);
125 	}
126 }
127 
128 /* initialize and setup credit distribution */
ath6kl_credit_setup(void * htc_handle,struct ath6kl_htc_credit_info * cred_info)129 int ath6kl_credit_setup(void *htc_handle,
130 			struct ath6kl_htc_credit_info *cred_info)
131 {
132 	u16 servicepriority[5];
133 
134 	memset(cred_info, 0, sizeof(struct ath6kl_htc_credit_info));
135 
136 	servicepriority[0] = WMI_CONTROL_SVC;  /* highest */
137 	servicepriority[1] = WMI_DATA_VO_SVC;
138 	servicepriority[2] = WMI_DATA_VI_SVC;
139 	servicepriority[3] = WMI_DATA_BE_SVC;
140 	servicepriority[4] = WMI_DATA_BK_SVC; /* lowest */
141 
142 	/* set priority list */
143 	ath6kl_htc_set_credit_dist(htc_handle, cred_info, servicepriority, 5);
144 
145 	return 0;
146 }
147 
148 /* reduce an ep's credits back to a set limit */
ath6kl_credit_reduce(struct ath6kl_htc_credit_info * cred_info,struct htc_endpoint_credit_dist * ep_dist,int limit)149 static void ath6kl_credit_reduce(struct ath6kl_htc_credit_info *cred_info,
150 				 struct htc_endpoint_credit_dist *ep_dist,
151 				 int limit)
152 {
153 	int credits;
154 
155 	ath6kl_dbg(ATH6KL_DBG_CREDIT, "credit reduce ep %d limit %d\n",
156 		   ep_dist->endpoint, limit);
157 
158 	ep_dist->cred_assngd = limit;
159 
160 	if (ep_dist->credits <= limit)
161 		return;
162 
163 	credits = ep_dist->credits - limit;
164 	ep_dist->credits -= credits;
165 	cred_info->cur_free_credits += credits;
166 }
167 
ath6kl_credit_update(struct ath6kl_htc_credit_info * cred_info,struct list_head * epdist_list)168 static void ath6kl_credit_update(struct ath6kl_htc_credit_info *cred_info,
169 				 struct list_head *epdist_list)
170 {
171 	struct htc_endpoint_credit_dist *cur_dist_list;
172 
173 	list_for_each_entry(cur_dist_list, epdist_list, list) {
174 		if (cur_dist_list->endpoint == ENDPOINT_0)
175 			continue;
176 
177 		if (cur_dist_list->cred_to_dist > 0) {
178 			cur_dist_list->credits +=
179 					cur_dist_list->cred_to_dist;
180 			cur_dist_list->cred_to_dist = 0;
181 			if (cur_dist_list->credits >
182 			    cur_dist_list->cred_assngd)
183 				ath6kl_credit_reduce(cred_info,
184 						cur_dist_list,
185 						cur_dist_list->cred_assngd);
186 
187 			if (cur_dist_list->credits >
188 			    cur_dist_list->cred_norm)
189 				ath6kl_credit_reduce(cred_info, cur_dist_list,
190 						     cur_dist_list->cred_norm);
191 
192 			if (!(cur_dist_list->dist_flags & HTC_EP_ACTIVE)) {
193 				if (cur_dist_list->txq_depth == 0)
194 					ath6kl_credit_reduce(cred_info,
195 							     cur_dist_list, 0);
196 			}
197 		}
198 	}
199 }
200 
201 /*
202  * HTC has an endpoint that needs credits, ep_dist is the endpoint in
203  * question.
204  */
ath6kl_credit_seek(struct ath6kl_htc_credit_info * cred_info,struct htc_endpoint_credit_dist * ep_dist)205 static void ath6kl_credit_seek(struct ath6kl_htc_credit_info *cred_info,
206 				struct htc_endpoint_credit_dist *ep_dist)
207 {
208 	struct htc_endpoint_credit_dist *curdist_list;
209 	int credits = 0;
210 	int need;
211 
212 	if (ep_dist->svc_id == WMI_CONTROL_SVC)
213 		goto out;
214 
215 	if ((ep_dist->svc_id == WMI_DATA_VI_SVC) ||
216 	    (ep_dist->svc_id == WMI_DATA_VO_SVC))
217 		if ((ep_dist->cred_assngd >= ep_dist->cred_norm))
218 			goto out;
219 
220 	/*
221 	 * For all other services, we follow a simple algorithm of:
222 	 *
223 	 * 1. checking the free pool for credits
224 	 * 2. checking lower priority endpoints for credits to take
225 	 */
226 
227 	credits = min(cred_info->cur_free_credits, ep_dist->seek_cred);
228 
229 	if (credits >= ep_dist->seek_cred)
230 		goto out;
231 
232 	/*
233 	 * We don't have enough in the free pool, try taking away from
234 	 * lower priority services The rule for taking away credits:
235 	 *
236 	 *   1. Only take from lower priority endpoints
237 	 *   2. Only take what is allocated above the minimum (never
238 	 *      starve an endpoint completely)
239 	 *   3. Only take what you need.
240 	 */
241 
242 	list_for_each_entry_reverse(curdist_list,
243 				    &cred_info->lowestpri_ep_dist,
244 				    list) {
245 		if (curdist_list == ep_dist)
246 			break;
247 
248 		need = ep_dist->seek_cred - cred_info->cur_free_credits;
249 
250 		if ((curdist_list->cred_assngd - need) >=
251 		     curdist_list->cred_min) {
252 			/*
253 			 * The current one has been allocated more than
254 			 * it's minimum and it has enough credits assigned
255 			 * above it's minimum to fulfill our need try to
256 			 * take away just enough to fulfill our need.
257 			 */
258 			ath6kl_credit_reduce(cred_info, curdist_list,
259 					     curdist_list->cred_assngd - need);
260 
261 			if (cred_info->cur_free_credits >=
262 			    ep_dist->seek_cred)
263 				break;
264 		}
265 
266 		if (curdist_list->endpoint == ENDPOINT_0)
267 			break;
268 	}
269 
270 	credits = min(cred_info->cur_free_credits, ep_dist->seek_cred);
271 
272 out:
273 	/* did we find some credits? */
274 	if (credits)
275 		ath6kl_credit_deposit(cred_info, ep_dist, credits);
276 
277 	ep_dist->seek_cred = 0;
278 }
279 
280 /* redistribute credits based on activity change */
ath6kl_credit_redistribute(struct ath6kl_htc_credit_info * info,struct list_head * ep_dist_list)281 static void ath6kl_credit_redistribute(struct ath6kl_htc_credit_info *info,
282 				       struct list_head *ep_dist_list)
283 {
284 	struct htc_endpoint_credit_dist *curdist_list;
285 
286 	list_for_each_entry(curdist_list, ep_dist_list, list) {
287 		if (curdist_list->endpoint == ENDPOINT_0)
288 			continue;
289 
290 		if ((curdist_list->svc_id == WMI_DATA_BK_SVC)  ||
291 		    (curdist_list->svc_id == WMI_DATA_BE_SVC))
292 			curdist_list->dist_flags |= HTC_EP_ACTIVE;
293 
294 		if ((curdist_list->svc_id != WMI_CONTROL_SVC) &&
295 		    !(curdist_list->dist_flags & HTC_EP_ACTIVE)) {
296 			if (curdist_list->txq_depth == 0)
297 				ath6kl_credit_reduce(info, curdist_list, 0);
298 			else
299 				ath6kl_credit_reduce(info,
300 						     curdist_list,
301 						     curdist_list->cred_min);
302 		}
303 	}
304 }
305 
306 /*
307  *
308  * This function is invoked whenever endpoints require credit
309  * distributions. A lock is held while this function is invoked, this
310  * function shall NOT block. The ep_dist_list is a list of distribution
311  * structures in prioritized order as defined by the call to the
312  * htc_set_credit_dist() api.
313  */
ath6kl_credit_distribute(struct ath6kl_htc_credit_info * cred_info,struct list_head * ep_dist_list,enum htc_credit_dist_reason reason)314 static void ath6kl_credit_distribute(struct ath6kl_htc_credit_info *cred_info,
315 				     struct list_head *ep_dist_list,
316 			      enum htc_credit_dist_reason reason)
317 {
318 	switch (reason) {
319 	case HTC_CREDIT_DIST_SEND_COMPLETE:
320 		ath6kl_credit_update(cred_info, ep_dist_list);
321 		break;
322 	case HTC_CREDIT_DIST_ACTIVITY_CHANGE:
323 		ath6kl_credit_redistribute(cred_info, ep_dist_list);
324 		break;
325 	default:
326 		break;
327 	}
328 
329 	WARN_ON(cred_info->cur_free_credits > cred_info->total_avail_credits);
330 	WARN_ON(cred_info->cur_free_credits < 0);
331 }
332 
ath6kl_htc_tx_buf_align(u8 ** buf,unsigned long len)333 static void ath6kl_htc_tx_buf_align(u8 **buf, unsigned long len)
334 {
335 	u8 *align_addr;
336 
337 	if (!IS_ALIGNED((unsigned long) *buf, 4)) {
338 		align_addr = PTR_ALIGN(*buf - 4, 4);
339 		memmove(align_addr, *buf, len);
340 		*buf = align_addr;
341 	}
342 }
343 
ath6kl_htc_tx_prep_pkt(struct htc_packet * packet,u8 flags,int ctrl0,int ctrl1)344 static void ath6kl_htc_tx_prep_pkt(struct htc_packet *packet, u8 flags,
345 				   int ctrl0, int ctrl1)
346 {
347 	struct htc_frame_hdr *hdr;
348 
349 	packet->buf -= HTC_HDR_LENGTH;
350 	hdr =  (struct htc_frame_hdr *)packet->buf;
351 
352 	/* Endianess? */
353 	put_unaligned((u16)packet->act_len, &hdr->payld_len);
354 	hdr->flags = flags;
355 	hdr->eid = packet->endpoint;
356 	hdr->ctrl[0] = ctrl0;
357 	hdr->ctrl[1] = ctrl1;
358 }
359 
htc_reclaim_txctrl_buf(struct htc_target * target,struct htc_packet * pkt)360 static void htc_reclaim_txctrl_buf(struct htc_target *target,
361 				   struct htc_packet *pkt)
362 {
363 	spin_lock_bh(&target->htc_lock);
364 	list_add_tail(&pkt->list, &target->free_ctrl_txbuf);
365 	spin_unlock_bh(&target->htc_lock);
366 }
367 
htc_get_control_buf(struct htc_target * target,bool tx)368 static struct htc_packet *htc_get_control_buf(struct htc_target *target,
369 					      bool tx)
370 {
371 	struct htc_packet *packet = NULL;
372 	struct list_head *buf_list;
373 
374 	buf_list = tx ? &target->free_ctrl_txbuf : &target->free_ctrl_rxbuf;
375 
376 	spin_lock_bh(&target->htc_lock);
377 
378 	if (list_empty(buf_list)) {
379 		spin_unlock_bh(&target->htc_lock);
380 		return NULL;
381 	}
382 
383 	packet = list_first_entry(buf_list, struct htc_packet, list);
384 	list_del(&packet->list);
385 	spin_unlock_bh(&target->htc_lock);
386 
387 	if (tx)
388 		packet->buf = packet->buf_start + HTC_HDR_LENGTH;
389 
390 	return packet;
391 }
392 
htc_tx_comp_update(struct htc_target * target,struct htc_endpoint * endpoint,struct htc_packet * packet)393 static void htc_tx_comp_update(struct htc_target *target,
394 			       struct htc_endpoint *endpoint,
395 			       struct htc_packet *packet)
396 {
397 	packet->completion = NULL;
398 	packet->buf += HTC_HDR_LENGTH;
399 
400 	if (!packet->status)
401 		return;
402 
403 	ath6kl_err("req failed (status:%d, ep:%d, len:%d creds:%d)\n",
404 		   packet->status, packet->endpoint, packet->act_len,
405 		   packet->info.tx.cred_used);
406 
407 	/* on failure to submit, reclaim credits for this packet */
408 	spin_lock_bh(&target->tx_lock);
409 	endpoint->cred_dist.cred_to_dist +=
410 				packet->info.tx.cred_used;
411 	endpoint->cred_dist.txq_depth = get_queue_depth(&endpoint->txq);
412 
413 	ath6kl_dbg(ATH6KL_DBG_HTC, "htc tx ctxt 0x%p dist 0x%p\n",
414 		   target->credit_info, &target->cred_dist_list);
415 
416 	ath6kl_credit_distribute(target->credit_info,
417 				 &target->cred_dist_list,
418 				 HTC_CREDIT_DIST_SEND_COMPLETE);
419 
420 	spin_unlock_bh(&target->tx_lock);
421 }
422 
htc_tx_complete(struct htc_endpoint * endpoint,struct list_head * txq)423 static void htc_tx_complete(struct htc_endpoint *endpoint,
424 			    struct list_head *txq)
425 {
426 	if (list_empty(txq))
427 		return;
428 
429 	ath6kl_dbg(ATH6KL_DBG_HTC,
430 		   "htc tx complete ep %d pkts %d\n",
431 		   endpoint->eid, get_queue_depth(txq));
432 
433 	ath6kl_tx_complete(endpoint->target->dev->ar, txq);
434 }
435 
htc_tx_comp_handler(struct htc_target * target,struct htc_packet * packet)436 static void htc_tx_comp_handler(struct htc_target *target,
437 				struct htc_packet *packet)
438 {
439 	struct htc_endpoint *endpoint = &target->endpoint[packet->endpoint];
440 	struct list_head container;
441 
442 	ath6kl_dbg(ATH6KL_DBG_HTC, "htc tx complete seqno %d\n",
443 		   packet->info.tx.seqno);
444 
445 	htc_tx_comp_update(target, endpoint, packet);
446 	INIT_LIST_HEAD(&container);
447 	list_add_tail(&packet->list, &container);
448 	/* do completion */
449 	htc_tx_complete(endpoint, &container);
450 }
451 
htc_async_tx_scat_complete(struct htc_target * target,struct hif_scatter_req * scat_req)452 static void htc_async_tx_scat_complete(struct htc_target *target,
453 				       struct hif_scatter_req *scat_req)
454 {
455 	struct htc_endpoint *endpoint;
456 	struct htc_packet *packet;
457 	struct list_head tx_compq;
458 	int i;
459 
460 	INIT_LIST_HEAD(&tx_compq);
461 
462 	ath6kl_dbg(ATH6KL_DBG_HTC,
463 		"htc tx scat complete len %d entries %d\n",
464 		scat_req->len, scat_req->scat_entries);
465 
466 	if (scat_req->status)
467 		ath6kl_err("send scatter req failed: %d\n", scat_req->status);
468 
469 	packet = scat_req->scat_list[0].packet;
470 	endpoint = &target->endpoint[packet->endpoint];
471 
472 	/* walk through the scatter list and process */
473 	for (i = 0; i < scat_req->scat_entries; i++) {
474 		packet = scat_req->scat_list[i].packet;
475 		if (!packet) {
476 			WARN_ON(1);
477 			return;
478 		}
479 
480 		packet->status = scat_req->status;
481 		htc_tx_comp_update(target, endpoint, packet);
482 		list_add_tail(&packet->list, &tx_compq);
483 	}
484 
485 	/* free scatter request */
486 	hif_scatter_req_add(target->dev->ar, scat_req);
487 
488 	/* complete all packets */
489 	htc_tx_complete(endpoint, &tx_compq);
490 }
491 
ath6kl_htc_tx_issue(struct htc_target * target,struct htc_packet * packet)492 static int ath6kl_htc_tx_issue(struct htc_target *target,
493 			       struct htc_packet *packet)
494 {
495 	int status;
496 	bool sync = false;
497 	u32 padded_len, send_len;
498 
499 	if (!packet->completion)
500 		sync = true;
501 
502 	send_len = packet->act_len + HTC_HDR_LENGTH;
503 
504 	padded_len = CALC_TXRX_PADDED_LEN(target, send_len);
505 
506 	ath6kl_dbg(ATH6KL_DBG_HTC,
507 		   "htc tx issue len %d seqno %d padded_len %d mbox 0x%X %s\n",
508 		   send_len, packet->info.tx.seqno, padded_len,
509 		   target->dev->ar->mbox_info.htc_addr,
510 		   sync ? "sync" : "async");
511 
512 	if (sync) {
513 		status = hif_read_write_sync(target->dev->ar,
514 				target->dev->ar->mbox_info.htc_addr,
515 				 packet->buf, padded_len,
516 				 HIF_WR_SYNC_BLOCK_INC);
517 
518 		packet->status = status;
519 		packet->buf += HTC_HDR_LENGTH;
520 	} else
521 		status = hif_write_async(target->dev->ar,
522 				target->dev->ar->mbox_info.htc_addr,
523 				packet->buf, padded_len,
524 				HIF_WR_ASYNC_BLOCK_INC, packet);
525 
526 	return status;
527 }
528 
htc_check_credits(struct htc_target * target,struct htc_endpoint * ep,u8 * flags,enum htc_endpoint_id eid,unsigned int len,int * req_cred)529 static int htc_check_credits(struct htc_target *target,
530 			     struct htc_endpoint *ep, u8 *flags,
531 			     enum htc_endpoint_id eid, unsigned int len,
532 			     int *req_cred)
533 {
534 
535 	*req_cred = (len > target->tgt_cred_sz) ?
536 		     DIV_ROUND_UP(len, target->tgt_cred_sz) : 1;
537 
538 	ath6kl_dbg(ATH6KL_DBG_CREDIT, "credit check need %d got %d\n",
539 		   *req_cred, ep->cred_dist.credits);
540 
541 	if (ep->cred_dist.credits < *req_cred) {
542 		if (eid == ENDPOINT_0)
543 			return -EINVAL;
544 
545 		/* Seek more credits */
546 		ep->cred_dist.seek_cred = *req_cred - ep->cred_dist.credits;
547 
548 		ath6kl_credit_seek(target->credit_info, &ep->cred_dist);
549 
550 		ep->cred_dist.seek_cred = 0;
551 
552 		if (ep->cred_dist.credits < *req_cred) {
553 			ath6kl_dbg(ATH6KL_DBG_CREDIT,
554 				   "credit not found for ep %d\n",
555 				   eid);
556 			return -EINVAL;
557 		}
558 	}
559 
560 	ep->cred_dist.credits -= *req_cred;
561 	ep->ep_st.cred_cosumd += *req_cred;
562 
563 	 /* When we are getting low on credits, ask for more */
564 	if (ep->cred_dist.credits < ep->cred_dist.cred_per_msg) {
565 		ep->cred_dist.seek_cred =
566 		ep->cred_dist.cred_per_msg - ep->cred_dist.credits;
567 
568 		ath6kl_credit_seek(target->credit_info, &ep->cred_dist);
569 
570 		/* see if we were successful in getting more */
571 		if (ep->cred_dist.credits < ep->cred_dist.cred_per_msg) {
572 			/* tell the target we need credits ASAP! */
573 			*flags |= HTC_FLAGS_NEED_CREDIT_UPDATE;
574 			ep->ep_st.cred_low_indicate += 1;
575 			ath6kl_dbg(ATH6KL_DBG_CREDIT,
576 				   "credit we need credits asap\n");
577 		}
578 	}
579 
580 	return 0;
581 }
582 
ath6kl_htc_tx_pkts_get(struct htc_target * target,struct htc_endpoint * endpoint,struct list_head * queue)583 static void ath6kl_htc_tx_pkts_get(struct htc_target *target,
584 				   struct htc_endpoint *endpoint,
585 				   struct list_head *queue)
586 {
587 	int req_cred;
588 	u8 flags;
589 	struct htc_packet *packet;
590 	unsigned int len;
591 
592 	while (true) {
593 
594 		flags = 0;
595 
596 		if (list_empty(&endpoint->txq))
597 			break;
598 		packet = list_first_entry(&endpoint->txq, struct htc_packet,
599 					  list);
600 
601 		ath6kl_dbg(ATH6KL_DBG_HTC,
602 			"htc tx got packet 0x%p queue depth %d\n",
603 			packet, get_queue_depth(&endpoint->txq));
604 
605 		len = CALC_TXRX_PADDED_LEN(target,
606 					   packet->act_len + HTC_HDR_LENGTH);
607 
608 		if (htc_check_credits(target, endpoint, &flags,
609 				      packet->endpoint, len, &req_cred))
610 			break;
611 
612 		/* now we can fully move onto caller's queue */
613 		packet = list_first_entry(&endpoint->txq, struct htc_packet,
614 					  list);
615 		list_move_tail(&packet->list, queue);
616 
617 		/* save the number of credits this packet consumed */
618 		packet->info.tx.cred_used = req_cred;
619 
620 		/* all TX packets are handled asynchronously */
621 		packet->completion = htc_tx_comp_handler;
622 		packet->context = target;
623 		endpoint->ep_st.tx_issued += 1;
624 
625 		/* save send flags */
626 		packet->info.tx.flags = flags;
627 		packet->info.tx.seqno = endpoint->seqno;
628 		endpoint->seqno++;
629 	}
630 }
631 
632 /* See if the padded tx length falls on a credit boundary */
htc_get_credit_padding(unsigned int cred_sz,int * len,struct htc_endpoint * ep)633 static int htc_get_credit_padding(unsigned int cred_sz, int *len,
634 				  struct htc_endpoint *ep)
635 {
636 	int rem_cred, cred_pad;
637 
638 	rem_cred = *len % cred_sz;
639 
640 	/* No padding needed */
641 	if  (!rem_cred)
642 		return 0;
643 
644 	if (!(ep->conn_flags & HTC_FLGS_TX_BNDL_PAD_EN))
645 		return -1;
646 
647 	/*
648 	 * The transfer consumes a "partial" credit, this
649 	 * packet cannot be bundled unless we add
650 	 * additional "dummy" padding (max 255 bytes) to
651 	 * consume the entire credit.
652 	 */
653 	cred_pad = *len < cred_sz ? (cred_sz - *len) : rem_cred;
654 
655 	if ((cred_pad > 0) && (cred_pad <= 255))
656 		*len += cred_pad;
657 	else
658 		/* The amount of padding is too large, send as non-bundled */
659 		return -1;
660 
661 	return cred_pad;
662 }
663 
ath6kl_htc_tx_setup_scat_list(struct htc_target * target,struct htc_endpoint * endpoint,struct hif_scatter_req * scat_req,int n_scat,struct list_head * queue)664 static int ath6kl_htc_tx_setup_scat_list(struct htc_target *target,
665 					 struct htc_endpoint *endpoint,
666 					 struct hif_scatter_req *scat_req,
667 					 int n_scat,
668 					 struct list_head *queue)
669 {
670 	struct htc_packet *packet;
671 	int i, len, rem_scat, cred_pad;
672 	int status = 0;
673 
674 	rem_scat = target->max_tx_bndl_sz;
675 
676 	for (i = 0; i < n_scat; i++) {
677 		scat_req->scat_list[i].packet = NULL;
678 
679 		if (list_empty(queue))
680 			break;
681 
682 		packet = list_first_entry(queue, struct htc_packet, list);
683 		len = CALC_TXRX_PADDED_LEN(target,
684 					   packet->act_len + HTC_HDR_LENGTH);
685 
686 		cred_pad = htc_get_credit_padding(target->tgt_cred_sz,
687 						  &len, endpoint);
688 		if (cred_pad < 0 || rem_scat < len) {
689 			status = -ENOSPC;
690 			break;
691 		}
692 
693 		rem_scat -= len;
694 		/* now remove it from the queue */
695 		list_del(&packet->list);
696 
697 		scat_req->scat_list[i].packet = packet;
698 		/* prepare packet and flag message as part of a send bundle */
699 		ath6kl_htc_tx_prep_pkt(packet,
700 				packet->info.tx.flags | HTC_FLAGS_SEND_BUNDLE,
701 				cred_pad, packet->info.tx.seqno);
702 		/* Make sure the buffer is 4-byte aligned */
703 		ath6kl_htc_tx_buf_align(&packet->buf,
704 					packet->act_len + HTC_HDR_LENGTH);
705 		scat_req->scat_list[i].buf = packet->buf;
706 		scat_req->scat_list[i].len = len;
707 
708 		scat_req->len += len;
709 		scat_req->scat_entries++;
710 		ath6kl_dbg(ATH6KL_DBG_HTC,
711 			   "htc tx adding (%d) pkt 0x%p seqno %d len %d remaining %d\n",
712 			   i, packet, packet->info.tx.seqno, len, rem_scat);
713 	}
714 
715 	/* Roll back scatter setup in case of any failure */
716 	if (scat_req->scat_entries < HTC_MIN_HTC_MSGS_TO_BUNDLE) {
717 		for (i = scat_req->scat_entries - 1; i >= 0; i--) {
718 			packet = scat_req->scat_list[i].packet;
719 			if (packet) {
720 				packet->buf += HTC_HDR_LENGTH;
721 				list_add(&packet->list, queue);
722 			}
723 		}
724 		return -EAGAIN;
725 	}
726 
727 	return status;
728 }
729 
730 /*
731  * Drain a queue and send as bundles this function may return without fully
732  * draining the queue when
733  *
734  *    1. scatter resources are exhausted
735  *    2. a message that will consume a partial credit will stop the
736  *    bundling process early
737  *    3. we drop below the minimum number of messages for a bundle
738  */
ath6kl_htc_tx_bundle(struct htc_endpoint * endpoint,struct list_head * queue,int * sent_bundle,int * n_bundle_pkts)739 static void ath6kl_htc_tx_bundle(struct htc_endpoint *endpoint,
740 				 struct list_head *queue,
741 				 int *sent_bundle, int *n_bundle_pkts)
742 {
743 	struct htc_target *target = endpoint->target;
744 	struct hif_scatter_req *scat_req = NULL;
745 	int n_scat, n_sent_bundle = 0, tot_pkts_bundle = 0;
746 	int status;
747 
748 	while (true) {
749 		status = 0;
750 		n_scat = get_queue_depth(queue);
751 		n_scat = min(n_scat, target->msg_per_bndl_max);
752 
753 		if (n_scat < HTC_MIN_HTC_MSGS_TO_BUNDLE)
754 			/* not enough to bundle */
755 			break;
756 
757 		scat_req = hif_scatter_req_get(target->dev->ar);
758 
759 		if (!scat_req) {
760 			/* no scatter resources  */
761 			ath6kl_dbg(ATH6KL_DBG_HTC,
762 				"htc tx no more scatter resources\n");
763 			break;
764 		}
765 
766 		ath6kl_dbg(ATH6KL_DBG_HTC, "htc tx pkts to scatter: %d\n",
767 			   n_scat);
768 
769 		scat_req->len = 0;
770 		scat_req->scat_entries = 0;
771 
772 		status = ath6kl_htc_tx_setup_scat_list(target, endpoint,
773 						       scat_req, n_scat,
774 						       queue);
775 		if (status == -EAGAIN) {
776 			hif_scatter_req_add(target->dev->ar, scat_req);
777 			break;
778 		}
779 
780 		/* send path is always asynchronous */
781 		scat_req->complete = htc_async_tx_scat_complete;
782 		n_sent_bundle++;
783 		tot_pkts_bundle += scat_req->scat_entries;
784 
785 		ath6kl_dbg(ATH6KL_DBG_HTC,
786 			   "htc tx scatter bytes %d entries %d\n",
787 			   scat_req->len, scat_req->scat_entries);
788 		ath6kl_hif_submit_scat_req(target->dev, scat_req, false);
789 
790 		if (status)
791 			break;
792 	}
793 
794 	*sent_bundle = n_sent_bundle;
795 	*n_bundle_pkts = tot_pkts_bundle;
796 	ath6kl_dbg(ATH6KL_DBG_HTC, "htc tx bundle sent %d pkts\n",
797 		   n_sent_bundle);
798 
799 	return;
800 }
801 
ath6kl_htc_tx_from_queue(struct htc_target * target,struct htc_endpoint * endpoint)802 static void ath6kl_htc_tx_from_queue(struct htc_target *target,
803 				     struct htc_endpoint *endpoint)
804 {
805 	struct list_head txq;
806 	struct htc_packet *packet;
807 	int bundle_sent;
808 	int n_pkts_bundle;
809 
810 	spin_lock_bh(&target->tx_lock);
811 
812 	endpoint->tx_proc_cnt++;
813 	if (endpoint->tx_proc_cnt > 1) {
814 		endpoint->tx_proc_cnt--;
815 		spin_unlock_bh(&target->tx_lock);
816 		ath6kl_dbg(ATH6KL_DBG_HTC, "htc tx busy\n");
817 		return;
818 	}
819 
820 	/*
821 	 * drain the endpoint TX queue for transmission as long
822 	 * as we have enough credits.
823 	 */
824 	INIT_LIST_HEAD(&txq);
825 
826 	while (true) {
827 
828 		if (list_empty(&endpoint->txq))
829 			break;
830 
831 		ath6kl_htc_tx_pkts_get(target, endpoint, &txq);
832 
833 		if (list_empty(&txq))
834 			break;
835 
836 		spin_unlock_bh(&target->tx_lock);
837 
838 		bundle_sent = 0;
839 		n_pkts_bundle = 0;
840 
841 		while (true) {
842 			/* try to send a bundle on each pass */
843 			if ((target->tx_bndl_enable) &&
844 			    (get_queue_depth(&txq) >=
845 			    HTC_MIN_HTC_MSGS_TO_BUNDLE)) {
846 				int temp1 = 0, temp2 = 0;
847 
848 				ath6kl_htc_tx_bundle(endpoint, &txq,
849 						     &temp1, &temp2);
850 				bundle_sent += temp1;
851 				n_pkts_bundle += temp2;
852 			}
853 
854 			if (list_empty(&txq))
855 				break;
856 
857 			packet = list_first_entry(&txq, struct htc_packet,
858 						  list);
859 			list_del(&packet->list);
860 
861 			ath6kl_htc_tx_prep_pkt(packet, packet->info.tx.flags,
862 					       0, packet->info.tx.seqno);
863 			ath6kl_htc_tx_issue(target, packet);
864 		}
865 
866 		spin_lock_bh(&target->tx_lock);
867 
868 		endpoint->ep_st.tx_bundles += bundle_sent;
869 		endpoint->ep_st.tx_pkt_bundled += n_pkts_bundle;
870 	}
871 
872 	endpoint->tx_proc_cnt = 0;
873 	spin_unlock_bh(&target->tx_lock);
874 }
875 
ath6kl_htc_tx_try(struct htc_target * target,struct htc_endpoint * endpoint,struct htc_packet * tx_pkt)876 static bool ath6kl_htc_tx_try(struct htc_target *target,
877 			      struct htc_endpoint *endpoint,
878 			      struct htc_packet *tx_pkt)
879 {
880 	struct htc_ep_callbacks ep_cb;
881 	int txq_depth;
882 	bool overflow = false;
883 
884 	ep_cb = endpoint->ep_cb;
885 
886 	spin_lock_bh(&target->tx_lock);
887 	txq_depth = get_queue_depth(&endpoint->txq);
888 	spin_unlock_bh(&target->tx_lock);
889 
890 	if (txq_depth >= endpoint->max_txq_depth)
891 		overflow = true;
892 
893 	if (overflow)
894 		ath6kl_dbg(ATH6KL_DBG_HTC,
895 			   "htc tx overflow ep %d depth %d max %d\n",
896 			   endpoint->eid, txq_depth,
897 			   endpoint->max_txq_depth);
898 
899 	if (overflow && ep_cb.tx_full) {
900 		if (ep_cb.tx_full(endpoint->target, tx_pkt) ==
901 		    HTC_SEND_FULL_DROP) {
902 			endpoint->ep_st.tx_dropped += 1;
903 			return false;
904 		}
905 	}
906 
907 	spin_lock_bh(&target->tx_lock);
908 	list_add_tail(&tx_pkt->list, &endpoint->txq);
909 	spin_unlock_bh(&target->tx_lock);
910 
911 	ath6kl_htc_tx_from_queue(target, endpoint);
912 
913 	return true;
914 }
915 
htc_chk_ep_txq(struct htc_target * target)916 static void htc_chk_ep_txq(struct htc_target *target)
917 {
918 	struct htc_endpoint *endpoint;
919 	struct htc_endpoint_credit_dist *cred_dist;
920 
921 	/*
922 	 * Run through the credit distribution list to see if there are
923 	 * packets queued. NOTE: no locks need to be taken since the
924 	 * distribution list is not dynamic (cannot be re-ordered) and we
925 	 * are not modifying any state.
926 	 */
927 	list_for_each_entry(cred_dist, &target->cred_dist_list, list) {
928 		endpoint = cred_dist->htc_ep;
929 
930 		spin_lock_bh(&target->tx_lock);
931 		if (!list_empty(&endpoint->txq)) {
932 			ath6kl_dbg(ATH6KL_DBG_HTC,
933 				   "htc creds ep %d credits %d pkts %d\n",
934 				   cred_dist->endpoint,
935 				   endpoint->cred_dist.credits,
936 				   get_queue_depth(&endpoint->txq));
937 			spin_unlock_bh(&target->tx_lock);
938 			/*
939 			 * Try to start the stalled queue, this list is
940 			 * ordered by priority. If there are credits
941 			 * available the highest priority queue will get a
942 			 * chance to reclaim credits from lower priority
943 			 * ones.
944 			 */
945 			ath6kl_htc_tx_from_queue(target, endpoint);
946 			spin_lock_bh(&target->tx_lock);
947 		}
948 		spin_unlock_bh(&target->tx_lock);
949 	}
950 }
951 
htc_setup_tx_complete(struct htc_target * target)952 static int htc_setup_tx_complete(struct htc_target *target)
953 {
954 	struct htc_packet *send_pkt = NULL;
955 	int status;
956 
957 	send_pkt = htc_get_control_buf(target, true);
958 
959 	if (!send_pkt)
960 		return -ENOMEM;
961 
962 	if (target->htc_tgt_ver >= HTC_VERSION_2P1) {
963 		struct htc_setup_comp_ext_msg *setup_comp_ext;
964 		u32 flags = 0;
965 
966 		setup_comp_ext =
967 		    (struct htc_setup_comp_ext_msg *)send_pkt->buf;
968 		memset(setup_comp_ext, 0, sizeof(*setup_comp_ext));
969 		setup_comp_ext->msg_id =
970 			cpu_to_le16(HTC_MSG_SETUP_COMPLETE_EX_ID);
971 
972 		if (target->msg_per_bndl_max > 0) {
973 			/* Indicate HTC bundling to the target */
974 			flags |= HTC_SETUP_COMP_FLG_RX_BNDL_EN;
975 			setup_comp_ext->msg_per_rxbndl =
976 						target->msg_per_bndl_max;
977 		}
978 
979 		memcpy(&setup_comp_ext->flags, &flags,
980 		       sizeof(setup_comp_ext->flags));
981 		set_htc_pkt_info(send_pkt, NULL, (u8 *) setup_comp_ext,
982 				       sizeof(struct htc_setup_comp_ext_msg),
983 				       ENDPOINT_0, HTC_SERVICE_TX_PACKET_TAG);
984 
985 	} else {
986 		struct htc_setup_comp_msg *setup_comp;
987 		setup_comp = (struct htc_setup_comp_msg *)send_pkt->buf;
988 		memset(setup_comp, 0, sizeof(struct htc_setup_comp_msg));
989 		setup_comp->msg_id = cpu_to_le16(HTC_MSG_SETUP_COMPLETE_ID);
990 		set_htc_pkt_info(send_pkt, NULL, (u8 *) setup_comp,
991 				       sizeof(struct htc_setup_comp_msg),
992 				       ENDPOINT_0, HTC_SERVICE_TX_PACKET_TAG);
993 	}
994 
995 	/* we want synchronous operation */
996 	send_pkt->completion = NULL;
997 	ath6kl_htc_tx_prep_pkt(send_pkt, 0, 0, 0);
998 	status = ath6kl_htc_tx_issue(target, send_pkt);
999 
1000 	if (send_pkt != NULL)
1001 		htc_reclaim_txctrl_buf(target, send_pkt);
1002 
1003 	return status;
1004 }
1005 
ath6kl_htc_set_credit_dist(struct htc_target * target,struct ath6kl_htc_credit_info * credit_info,u16 srvc_pri_order[],int list_len)1006 void ath6kl_htc_set_credit_dist(struct htc_target *target,
1007 				struct ath6kl_htc_credit_info *credit_info,
1008 				u16 srvc_pri_order[], int list_len)
1009 {
1010 	struct htc_endpoint *endpoint;
1011 	int i, ep;
1012 
1013 	target->credit_info = credit_info;
1014 
1015 	list_add_tail(&target->endpoint[ENDPOINT_0].cred_dist.list,
1016 		      &target->cred_dist_list);
1017 
1018 	for (i = 0; i < list_len; i++) {
1019 		for (ep = ENDPOINT_1; ep < ENDPOINT_MAX; ep++) {
1020 			endpoint = &target->endpoint[ep];
1021 			if (endpoint->svc_id == srvc_pri_order[i]) {
1022 				list_add_tail(&endpoint->cred_dist.list,
1023 					      &target->cred_dist_list);
1024 				break;
1025 			}
1026 		}
1027 		if (ep >= ENDPOINT_MAX) {
1028 			WARN_ON(1);
1029 			return;
1030 		}
1031 	}
1032 }
1033 
ath6kl_htc_tx(struct htc_target * target,struct htc_packet * packet)1034 int ath6kl_htc_tx(struct htc_target *target, struct htc_packet *packet)
1035 {
1036 	struct htc_endpoint *endpoint;
1037 	struct list_head queue;
1038 
1039 	ath6kl_dbg(ATH6KL_DBG_HTC,
1040 		   "htc tx ep id %d buf 0x%p len %d\n",
1041 		   packet->endpoint, packet->buf, packet->act_len);
1042 
1043 	if (packet->endpoint >= ENDPOINT_MAX) {
1044 		WARN_ON(1);
1045 		return -EINVAL;
1046 	}
1047 
1048 	endpoint = &target->endpoint[packet->endpoint];
1049 
1050 	if (!ath6kl_htc_tx_try(target, endpoint, packet)) {
1051 		packet->status = (target->htc_flags & HTC_OP_STATE_STOPPING) ?
1052 				 -ECANCELED : -ENOSPC;
1053 		INIT_LIST_HEAD(&queue);
1054 		list_add(&packet->list, &queue);
1055 		htc_tx_complete(endpoint, &queue);
1056 	}
1057 
1058 	return 0;
1059 }
1060 
1061 /* flush endpoint TX queue */
ath6kl_htc_flush_txep(struct htc_target * target,enum htc_endpoint_id eid,u16 tag)1062 void ath6kl_htc_flush_txep(struct htc_target *target,
1063 			   enum htc_endpoint_id eid, u16 tag)
1064 {
1065 	struct htc_packet *packet, *tmp_pkt;
1066 	struct list_head discard_q, container;
1067 	struct htc_endpoint *endpoint = &target->endpoint[eid];
1068 
1069 	if (!endpoint->svc_id) {
1070 		WARN_ON(1);
1071 		return;
1072 	}
1073 
1074 	/* initialize the discard queue */
1075 	INIT_LIST_HEAD(&discard_q);
1076 
1077 	spin_lock_bh(&target->tx_lock);
1078 
1079 	list_for_each_entry_safe(packet, tmp_pkt, &endpoint->txq, list) {
1080 		if ((tag == HTC_TX_PACKET_TAG_ALL) ||
1081 		    (tag == packet->info.tx.tag))
1082 			list_move_tail(&packet->list, &discard_q);
1083 	}
1084 
1085 	spin_unlock_bh(&target->tx_lock);
1086 
1087 	list_for_each_entry_safe(packet, tmp_pkt, &discard_q, list) {
1088 		packet->status = -ECANCELED;
1089 		list_del(&packet->list);
1090 		ath6kl_dbg(ATH6KL_DBG_HTC,
1091 			"htc tx flushing pkt 0x%p len %d  ep %d tag 0x%x\n",
1092 			packet, packet->act_len,
1093 			packet->endpoint, packet->info.tx.tag);
1094 
1095 		INIT_LIST_HEAD(&container);
1096 		list_add_tail(&packet->list, &container);
1097 		htc_tx_complete(endpoint, &container);
1098 	}
1099 
1100 }
1101 
ath6kl_htc_flush_txep_all(struct htc_target * target)1102 static void ath6kl_htc_flush_txep_all(struct htc_target *target)
1103 {
1104 	struct htc_endpoint *endpoint;
1105 	int i;
1106 
1107 	dump_cred_dist_stats(target);
1108 
1109 	for (i = ENDPOINT_0; i < ENDPOINT_MAX; i++) {
1110 		endpoint = &target->endpoint[i];
1111 		if (endpoint->svc_id == 0)
1112 			/* not in use.. */
1113 			continue;
1114 		ath6kl_htc_flush_txep(target, i, HTC_TX_PACKET_TAG_ALL);
1115 	}
1116 }
1117 
ath6kl_htc_indicate_activity_change(struct htc_target * target,enum htc_endpoint_id eid,bool active)1118 void ath6kl_htc_indicate_activity_change(struct htc_target *target,
1119 					 enum htc_endpoint_id eid, bool active)
1120 {
1121 	struct htc_endpoint *endpoint = &target->endpoint[eid];
1122 	bool dist = false;
1123 
1124 	if (endpoint->svc_id == 0) {
1125 		WARN_ON(1);
1126 		return;
1127 	}
1128 
1129 	spin_lock_bh(&target->tx_lock);
1130 
1131 	if (active) {
1132 		if (!(endpoint->cred_dist.dist_flags & HTC_EP_ACTIVE)) {
1133 			endpoint->cred_dist.dist_flags |= HTC_EP_ACTIVE;
1134 			dist = true;
1135 		}
1136 	} else {
1137 		if (endpoint->cred_dist.dist_flags & HTC_EP_ACTIVE) {
1138 			endpoint->cred_dist.dist_flags &= ~HTC_EP_ACTIVE;
1139 			dist = true;
1140 		}
1141 	}
1142 
1143 	if (dist) {
1144 		endpoint->cred_dist.txq_depth =
1145 			get_queue_depth(&endpoint->txq);
1146 
1147 		ath6kl_dbg(ATH6KL_DBG_HTC,
1148 			   "htc tx activity ctxt 0x%p dist 0x%p\n",
1149 			   target->credit_info, &target->cred_dist_list);
1150 
1151 		ath6kl_credit_distribute(target->credit_info,
1152 					 &target->cred_dist_list,
1153 					 HTC_CREDIT_DIST_ACTIVITY_CHANGE);
1154 	}
1155 
1156 	spin_unlock_bh(&target->tx_lock);
1157 
1158 	if (dist && !active)
1159 		htc_chk_ep_txq(target);
1160 }
1161 
1162 /* HTC Rx */
1163 
ath6kl_htc_rx_update_stats(struct htc_endpoint * endpoint,int n_look_ahds)1164 static inline void ath6kl_htc_rx_update_stats(struct htc_endpoint *endpoint,
1165 					      int n_look_ahds)
1166 {
1167 	endpoint->ep_st.rx_pkts++;
1168 	if (n_look_ahds == 1)
1169 		endpoint->ep_st.rx_lkahds++;
1170 	else if (n_look_ahds > 1)
1171 		endpoint->ep_st.rx_bundle_lkahd++;
1172 }
1173 
htc_valid_rx_frame_len(struct htc_target * target,enum htc_endpoint_id eid,int len)1174 static inline bool htc_valid_rx_frame_len(struct htc_target *target,
1175 					  enum htc_endpoint_id eid, int len)
1176 {
1177 	return (eid == target->dev->ar->ctrl_ep) ?
1178 		len <= ATH6KL_BUFFER_SIZE : len <= ATH6KL_AMSDU_BUFFER_SIZE;
1179 }
1180 
htc_add_rxbuf(struct htc_target * target,struct htc_packet * packet)1181 static int htc_add_rxbuf(struct htc_target *target, struct htc_packet *packet)
1182 {
1183 	struct list_head queue;
1184 
1185 	INIT_LIST_HEAD(&queue);
1186 	list_add_tail(&packet->list, &queue);
1187 	return ath6kl_htc_add_rxbuf_multiple(target, &queue);
1188 }
1189 
htc_reclaim_rxbuf(struct htc_target * target,struct htc_packet * packet,struct htc_endpoint * ep)1190 static void htc_reclaim_rxbuf(struct htc_target *target,
1191 			      struct htc_packet *packet,
1192 			      struct htc_endpoint *ep)
1193 {
1194 	if (packet->info.rx.rx_flags & HTC_RX_PKT_NO_RECYCLE) {
1195 		htc_rxpkt_reset(packet);
1196 		packet->status = -ECANCELED;
1197 		ep->ep_cb.rx(ep->target, packet);
1198 	} else {
1199 		htc_rxpkt_reset(packet);
1200 		htc_add_rxbuf((void *)(target), packet);
1201 	}
1202 }
1203 
reclaim_rx_ctrl_buf(struct htc_target * target,struct htc_packet * packet)1204 static void reclaim_rx_ctrl_buf(struct htc_target *target,
1205 				struct htc_packet *packet)
1206 {
1207 	spin_lock_bh(&target->htc_lock);
1208 	list_add_tail(&packet->list, &target->free_ctrl_rxbuf);
1209 	spin_unlock_bh(&target->htc_lock);
1210 }
1211 
ath6kl_htc_rx_packet(struct htc_target * target,struct htc_packet * packet,u32 rx_len)1212 static int ath6kl_htc_rx_packet(struct htc_target *target,
1213 				struct htc_packet *packet,
1214 				u32 rx_len)
1215 {
1216 	struct ath6kl_device *dev = target->dev;
1217 	u32 padded_len;
1218 	int status;
1219 
1220 	padded_len = CALC_TXRX_PADDED_LEN(target, rx_len);
1221 
1222 	if (padded_len > packet->buf_len) {
1223 		ath6kl_err("not enough receive space for packet - padlen %d recvlen %d bufferlen %d\n",
1224 			   padded_len, rx_len, packet->buf_len);
1225 		return -ENOMEM;
1226 	}
1227 
1228 	ath6kl_dbg(ATH6KL_DBG_HTC,
1229 		   "htc rx 0x%p hdr x%x len %d mbox 0x%x\n",
1230 		   packet, packet->info.rx.exp_hdr,
1231 		   padded_len, dev->ar->mbox_info.htc_addr);
1232 
1233 	status = hif_read_write_sync(dev->ar,
1234 				     dev->ar->mbox_info.htc_addr,
1235 				     packet->buf, padded_len,
1236 				     HIF_RD_SYNC_BLOCK_FIX);
1237 
1238 	packet->status = status;
1239 
1240 	return status;
1241 }
1242 
1243 /*
1244  * optimization for recv packets, we can indicate a
1245  * "hint" that there are more  single-packets to fetch
1246  * on this endpoint.
1247  */
ath6kl_htc_rx_set_indicate(u32 lk_ahd,struct htc_endpoint * endpoint,struct htc_packet * packet)1248 static void ath6kl_htc_rx_set_indicate(u32 lk_ahd,
1249 				       struct htc_endpoint *endpoint,
1250 				       struct htc_packet *packet)
1251 {
1252 	struct htc_frame_hdr *htc_hdr = (struct htc_frame_hdr *)&lk_ahd;
1253 
1254 	if (htc_hdr->eid == packet->endpoint) {
1255 		if (!list_empty(&endpoint->rx_bufq))
1256 			packet->info.rx.indicat_flags |=
1257 					HTC_RX_FLAGS_INDICATE_MORE_PKTS;
1258 	}
1259 }
1260 
ath6kl_htc_rx_chk_water_mark(struct htc_endpoint * endpoint)1261 static void ath6kl_htc_rx_chk_water_mark(struct htc_endpoint *endpoint)
1262 {
1263 	struct htc_ep_callbacks ep_cb = endpoint->ep_cb;
1264 
1265 	if (ep_cb.rx_refill_thresh > 0) {
1266 		spin_lock_bh(&endpoint->target->rx_lock);
1267 		if (get_queue_depth(&endpoint->rx_bufq)
1268 		    < ep_cb.rx_refill_thresh) {
1269 			spin_unlock_bh(&endpoint->target->rx_lock);
1270 			ep_cb.rx_refill(endpoint->target, endpoint->eid);
1271 			return;
1272 		}
1273 		spin_unlock_bh(&endpoint->target->rx_lock);
1274 	}
1275 }
1276 
1277 /* This function is called with rx_lock held */
ath6kl_htc_rx_setup(struct htc_target * target,struct htc_endpoint * ep,u32 * lk_ahds,struct list_head * queue,int n_msg)1278 static int ath6kl_htc_rx_setup(struct htc_target *target,
1279 			       struct htc_endpoint *ep,
1280 			       u32 *lk_ahds, struct list_head *queue, int n_msg)
1281 {
1282 	struct htc_packet *packet;
1283 	/* FIXME: type of lk_ahds can't be right */
1284 	struct htc_frame_hdr *htc_hdr = (struct htc_frame_hdr *)lk_ahds;
1285 	struct htc_ep_callbacks ep_cb;
1286 	int status = 0, j, full_len;
1287 	bool no_recycle;
1288 
1289 	full_len = CALC_TXRX_PADDED_LEN(target,
1290 					le16_to_cpu(htc_hdr->payld_len) +
1291 					sizeof(*htc_hdr));
1292 
1293 	if (!htc_valid_rx_frame_len(target, ep->eid, full_len)) {
1294 		ath6kl_warn("Rx buffer requested with invalid length\n");
1295 		return -EINVAL;
1296 	}
1297 
1298 	ep_cb = ep->ep_cb;
1299 	for (j = 0; j < n_msg; j++) {
1300 
1301 		/*
1302 		 * Reset flag, any packets allocated using the
1303 		 * rx_alloc() API cannot be recycled on
1304 		 * cleanup,they must be explicitly returned.
1305 		 */
1306 		no_recycle = false;
1307 
1308 		if (ep_cb.rx_allocthresh &&
1309 		    (full_len > ep_cb.rx_alloc_thresh)) {
1310 			ep->ep_st.rx_alloc_thresh_hit += 1;
1311 			ep->ep_st.rxalloc_thresh_byte +=
1312 				le16_to_cpu(htc_hdr->payld_len);
1313 
1314 			spin_unlock_bh(&target->rx_lock);
1315 			no_recycle = true;
1316 
1317 			packet = ep_cb.rx_allocthresh(ep->target, ep->eid,
1318 						      full_len);
1319 			spin_lock_bh(&target->rx_lock);
1320 		} else {
1321 			/* refill handler is being used */
1322 			if (list_empty(&ep->rx_bufq)) {
1323 				if (ep_cb.rx_refill) {
1324 					spin_unlock_bh(&target->rx_lock);
1325 					ep_cb.rx_refill(ep->target, ep->eid);
1326 					spin_lock_bh(&target->rx_lock);
1327 				}
1328 			}
1329 
1330 			if (list_empty(&ep->rx_bufq))
1331 				packet = NULL;
1332 			else {
1333 				packet = list_first_entry(&ep->rx_bufq,
1334 						struct htc_packet, list);
1335 				list_del(&packet->list);
1336 			}
1337 		}
1338 
1339 		if (!packet) {
1340 			target->rx_st_flags |= HTC_RECV_WAIT_BUFFERS;
1341 			target->ep_waiting = ep->eid;
1342 			return -ENOSPC;
1343 		}
1344 
1345 		/* clear flags */
1346 		packet->info.rx.rx_flags = 0;
1347 		packet->info.rx.indicat_flags = 0;
1348 		packet->status = 0;
1349 
1350 		if (no_recycle)
1351 			/*
1352 			 * flag that these packets cannot be
1353 			 * recycled, they have to be returned to
1354 			 * the user
1355 			 */
1356 			packet->info.rx.rx_flags |= HTC_RX_PKT_NO_RECYCLE;
1357 
1358 		/* Caller needs to free this upon any failure */
1359 		list_add_tail(&packet->list, queue);
1360 
1361 		if (target->htc_flags & HTC_OP_STATE_STOPPING) {
1362 			status = -ECANCELED;
1363 			break;
1364 		}
1365 
1366 		if (j) {
1367 			packet->info.rx.rx_flags |= HTC_RX_PKT_REFRESH_HDR;
1368 			packet->info.rx.exp_hdr = 0xFFFFFFFF;
1369 		} else
1370 			/* set expected look ahead */
1371 			packet->info.rx.exp_hdr = *lk_ahds;
1372 
1373 		packet->act_len = le16_to_cpu(htc_hdr->payld_len) +
1374 			HTC_HDR_LENGTH;
1375 	}
1376 
1377 	return status;
1378 }
1379 
ath6kl_htc_rx_alloc(struct htc_target * target,u32 lk_ahds[],int msg,struct htc_endpoint * endpoint,struct list_head * queue)1380 static int ath6kl_htc_rx_alloc(struct htc_target *target,
1381 			       u32 lk_ahds[], int msg,
1382 			       struct htc_endpoint *endpoint,
1383 			       struct list_head *queue)
1384 {
1385 	int status = 0;
1386 	struct htc_packet *packet, *tmp_pkt;
1387 	struct htc_frame_hdr *htc_hdr;
1388 	int i, n_msg;
1389 
1390 	spin_lock_bh(&target->rx_lock);
1391 
1392 	for (i = 0; i < msg; i++) {
1393 
1394 		htc_hdr = (struct htc_frame_hdr *)&lk_ahds[i];
1395 
1396 		if (htc_hdr->eid >= ENDPOINT_MAX) {
1397 			ath6kl_err("invalid ep in look-ahead: %d\n",
1398 				   htc_hdr->eid);
1399 			status = -ENOMEM;
1400 			break;
1401 		}
1402 
1403 		if (htc_hdr->eid != endpoint->eid) {
1404 			ath6kl_err("invalid ep in look-ahead: %d should be : %d (index:%d)\n",
1405 				   htc_hdr->eid, endpoint->eid, i);
1406 			status = -ENOMEM;
1407 			break;
1408 		}
1409 
1410 		if (le16_to_cpu(htc_hdr->payld_len) > HTC_MAX_PAYLOAD_LENGTH) {
1411 			ath6kl_err("payload len %d exceeds max htc : %d !\n",
1412 				   htc_hdr->payld_len,
1413 				   (u32) HTC_MAX_PAYLOAD_LENGTH);
1414 			status = -ENOMEM;
1415 			break;
1416 		}
1417 
1418 		if (endpoint->svc_id == 0) {
1419 			ath6kl_err("ep %d is not connected !\n", htc_hdr->eid);
1420 			status = -ENOMEM;
1421 			break;
1422 		}
1423 
1424 		if (htc_hdr->flags & HTC_FLG_RX_BNDL_CNT) {
1425 			/*
1426 			 * HTC header indicates that every packet to follow
1427 			 * has the same padded length so that it can be
1428 			 * optimally fetched as a full bundle.
1429 			 */
1430 			n_msg = (htc_hdr->flags & HTC_FLG_RX_BNDL_CNT) >>
1431 				HTC_FLG_RX_BNDL_CNT_S;
1432 
1433 			/* the count doesn't include the starter frame */
1434 			n_msg++;
1435 			if (n_msg > target->msg_per_bndl_max) {
1436 				status = -ENOMEM;
1437 				break;
1438 			}
1439 
1440 			endpoint->ep_st.rx_bundle_from_hdr += 1;
1441 			ath6kl_dbg(ATH6KL_DBG_HTC,
1442 				   "htc rx bundle pkts %d\n",
1443 				   n_msg);
1444 		} else
1445 			/* HTC header only indicates 1 message to fetch */
1446 			n_msg = 1;
1447 
1448 		/* Setup packet buffers for each message */
1449 		status = ath6kl_htc_rx_setup(target, endpoint, &lk_ahds[i],
1450 					     queue, n_msg);
1451 
1452 		/*
1453 		 * This is due to unavailabilty of buffers to rx entire data.
1454 		 * Return no error so that free buffers from queue can be used
1455 		 * to receive partial data.
1456 		 */
1457 		if (status == -ENOSPC) {
1458 			spin_unlock_bh(&target->rx_lock);
1459 			return 0;
1460 		}
1461 
1462 		if (status)
1463 			break;
1464 	}
1465 
1466 	spin_unlock_bh(&target->rx_lock);
1467 
1468 	if (status) {
1469 		list_for_each_entry_safe(packet, tmp_pkt, queue, list) {
1470 			list_del(&packet->list);
1471 			htc_reclaim_rxbuf(target, packet,
1472 					  &target->endpoint[packet->endpoint]);
1473 		}
1474 	}
1475 
1476 	return status;
1477 }
1478 
htc_ctrl_rx(struct htc_target * context,struct htc_packet * packets)1479 static void htc_ctrl_rx(struct htc_target *context, struct htc_packet *packets)
1480 {
1481 	if (packets->endpoint != ENDPOINT_0) {
1482 		WARN_ON(1);
1483 		return;
1484 	}
1485 
1486 	if (packets->status == -ECANCELED) {
1487 		reclaim_rx_ctrl_buf(context, packets);
1488 		return;
1489 	}
1490 
1491 	if (packets->act_len > 0) {
1492 		ath6kl_err("htc_ctrl_rx, got message with len:%zu\n",
1493 			packets->act_len + HTC_HDR_LENGTH);
1494 
1495 		ath6kl_dbg_dump(ATH6KL_DBG_HTC,
1496 				"htc rx unexpected endpoint 0 message", "",
1497 				packets->buf - HTC_HDR_LENGTH,
1498 				packets->act_len + HTC_HDR_LENGTH);
1499 	}
1500 
1501 	htc_reclaim_rxbuf(context, packets, &context->endpoint[0]);
1502 }
1503 
htc_proc_cred_rpt(struct htc_target * target,struct htc_credit_report * rpt,int n_entries,enum htc_endpoint_id from_ep)1504 static void htc_proc_cred_rpt(struct htc_target *target,
1505 			      struct htc_credit_report *rpt,
1506 			      int n_entries,
1507 			      enum htc_endpoint_id from_ep)
1508 {
1509 	struct htc_endpoint *endpoint;
1510 	int tot_credits = 0, i;
1511 	bool dist = false;
1512 
1513 	spin_lock_bh(&target->tx_lock);
1514 
1515 	for (i = 0; i < n_entries; i++, rpt++) {
1516 		if (rpt->eid >= ENDPOINT_MAX) {
1517 			WARN_ON(1);
1518 			spin_unlock_bh(&target->tx_lock);
1519 			return;
1520 		}
1521 
1522 		endpoint = &target->endpoint[rpt->eid];
1523 
1524 		ath6kl_dbg(ATH6KL_DBG_CREDIT,
1525 			   "credit report ep %d credits %d\n",
1526 			   rpt->eid, rpt->credits);
1527 
1528 		endpoint->ep_st.tx_cred_rpt += 1;
1529 		endpoint->ep_st.cred_retnd += rpt->credits;
1530 
1531 		if (from_ep == rpt->eid) {
1532 			/*
1533 			 * This credit report arrived on the same endpoint
1534 			 * indicating it arrived in an RX packet.
1535 			 */
1536 			endpoint->ep_st.cred_from_rx += rpt->credits;
1537 			endpoint->ep_st.cred_rpt_from_rx += 1;
1538 		} else if (from_ep == ENDPOINT_0) {
1539 			/* credit arrived on endpoint 0 as a NULL message */
1540 			endpoint->ep_st.cred_from_ep0 += rpt->credits;
1541 			endpoint->ep_st.cred_rpt_ep0 += 1;
1542 		} else {
1543 			endpoint->ep_st.cred_from_other += rpt->credits;
1544 			endpoint->ep_st.cred_rpt_from_other += 1;
1545 		}
1546 
1547 		if (rpt->eid == ENDPOINT_0)
1548 			/* always give endpoint 0 credits back */
1549 			endpoint->cred_dist.credits += rpt->credits;
1550 		else {
1551 			endpoint->cred_dist.cred_to_dist += rpt->credits;
1552 			dist = true;
1553 		}
1554 
1555 		/*
1556 		 * Refresh tx depth for distribution function that will
1557 		 * recover these credits NOTE: this is only valid when
1558 		 * there are credits to recover!
1559 		 */
1560 		endpoint->cred_dist.txq_depth =
1561 			get_queue_depth(&endpoint->txq);
1562 
1563 		tot_credits += rpt->credits;
1564 	}
1565 
1566 	if (dist) {
1567 		/*
1568 		 * This was a credit return based on a completed send
1569 		 * operations note, this is done with the lock held
1570 		 */
1571 		ath6kl_credit_distribute(target->credit_info,
1572 					 &target->cred_dist_list,
1573 					 HTC_CREDIT_DIST_SEND_COMPLETE);
1574 	}
1575 
1576 	spin_unlock_bh(&target->tx_lock);
1577 
1578 	if (tot_credits)
1579 		htc_chk_ep_txq(target);
1580 }
1581 
htc_parse_trailer(struct htc_target * target,struct htc_record_hdr * record,u8 * record_buf,u32 * next_lk_ahds,enum htc_endpoint_id endpoint,int * n_lk_ahds)1582 static int htc_parse_trailer(struct htc_target *target,
1583 			     struct htc_record_hdr *record,
1584 			     u8 *record_buf, u32 *next_lk_ahds,
1585 			     enum htc_endpoint_id endpoint,
1586 			     int *n_lk_ahds)
1587 {
1588 	struct htc_bundle_lkahd_rpt *bundle_lkahd_rpt;
1589 	struct htc_lookahead_report *lk_ahd;
1590 	int len;
1591 
1592 	switch (record->rec_id) {
1593 	case HTC_RECORD_CREDITS:
1594 		len = record->len / sizeof(struct htc_credit_report);
1595 		if (!len) {
1596 			WARN_ON(1);
1597 			return -EINVAL;
1598 		}
1599 
1600 		htc_proc_cred_rpt(target,
1601 				  (struct htc_credit_report *) record_buf,
1602 				  len, endpoint);
1603 		break;
1604 	case HTC_RECORD_LOOKAHEAD:
1605 		len = record->len / sizeof(*lk_ahd);
1606 		if (!len) {
1607 			WARN_ON(1);
1608 			return -EINVAL;
1609 		}
1610 
1611 		lk_ahd = (struct htc_lookahead_report *) record_buf;
1612 		if ((lk_ahd->pre_valid == ((~lk_ahd->post_valid) & 0xFF))
1613 		    && next_lk_ahds) {
1614 
1615 			ath6kl_dbg(ATH6KL_DBG_HTC,
1616 				   "htc rx lk_ahd found pre_valid 0x%x post_valid 0x%x\n",
1617 				   lk_ahd->pre_valid, lk_ahd->post_valid);
1618 
1619 			/* look ahead bytes are valid, copy them over */
1620 			memcpy((u8 *)&next_lk_ahds[0], lk_ahd->lk_ahd, 4);
1621 
1622 			ath6kl_dbg_dump(ATH6KL_DBG_HTC,
1623 					"htc rx next look ahead",
1624 					"", next_lk_ahds, 4);
1625 
1626 			*n_lk_ahds = 1;
1627 		}
1628 		break;
1629 	case HTC_RECORD_LOOKAHEAD_BUNDLE:
1630 		len = record->len / sizeof(*bundle_lkahd_rpt);
1631 		if (!len || (len > HTC_HOST_MAX_MSG_PER_BUNDLE)) {
1632 			WARN_ON(1);
1633 			return -EINVAL;
1634 		}
1635 
1636 		if (next_lk_ahds) {
1637 			int i;
1638 
1639 			bundle_lkahd_rpt =
1640 				(struct htc_bundle_lkahd_rpt *) record_buf;
1641 
1642 			ath6kl_dbg_dump(ATH6KL_DBG_HTC, "htc rx bundle lk_ahd",
1643 					"", record_buf, record->len);
1644 
1645 			for (i = 0; i < len; i++) {
1646 				memcpy((u8 *)&next_lk_ahds[i],
1647 				       bundle_lkahd_rpt->lk_ahd, 4);
1648 				bundle_lkahd_rpt++;
1649 			}
1650 
1651 			*n_lk_ahds = i;
1652 		}
1653 		break;
1654 	default:
1655 		ath6kl_err("unhandled record: id:%d len:%d\n",
1656 			   record->rec_id, record->len);
1657 		break;
1658 	}
1659 
1660 	return 0;
1661 
1662 }
1663 
htc_proc_trailer(struct htc_target * target,u8 * buf,int len,u32 * next_lk_ahds,int * n_lk_ahds,enum htc_endpoint_id endpoint)1664 static int htc_proc_trailer(struct htc_target *target,
1665 			    u8 *buf, int len, u32 *next_lk_ahds,
1666 			    int *n_lk_ahds, enum htc_endpoint_id endpoint)
1667 {
1668 	struct htc_record_hdr *record;
1669 	int orig_len;
1670 	int status;
1671 	u8 *record_buf;
1672 	u8 *orig_buf;
1673 
1674 	ath6kl_dbg(ATH6KL_DBG_HTC, "htc rx trailer len %d\n", len);
1675 	ath6kl_dbg_dump(ATH6KL_DBG_HTC, NULL, "", buf, len);
1676 
1677 	orig_buf = buf;
1678 	orig_len = len;
1679 	status = 0;
1680 
1681 	while (len > 0) {
1682 
1683 		if (len < sizeof(struct htc_record_hdr)) {
1684 			status = -ENOMEM;
1685 			break;
1686 		}
1687 		/* these are byte aligned structs */
1688 		record = (struct htc_record_hdr *) buf;
1689 		len -= sizeof(struct htc_record_hdr);
1690 		buf += sizeof(struct htc_record_hdr);
1691 
1692 		if (record->len > len) {
1693 			ath6kl_err("invalid record len: %d (id:%d) buf has: %d bytes left\n",
1694 				   record->len, record->rec_id, len);
1695 			status = -ENOMEM;
1696 			break;
1697 		}
1698 		record_buf = buf;
1699 
1700 		status = htc_parse_trailer(target, record, record_buf,
1701 					   next_lk_ahds, endpoint, n_lk_ahds);
1702 
1703 		if (status)
1704 			break;
1705 
1706 		/* advance buffer past this record for next time around */
1707 		buf += record->len;
1708 		len -= record->len;
1709 	}
1710 
1711 	if (status)
1712 		ath6kl_dbg_dump(ATH6KL_DBG_HTC, "htc rx bad trailer",
1713 				"", orig_buf, orig_len);
1714 
1715 	return status;
1716 }
1717 
ath6kl_htc_rx_process_hdr(struct htc_target * target,struct htc_packet * packet,u32 * next_lkahds,int * n_lkahds)1718 static int ath6kl_htc_rx_process_hdr(struct htc_target *target,
1719 				     struct htc_packet *packet,
1720 				     u32 *next_lkahds, int *n_lkahds)
1721 {
1722 	int status = 0;
1723 	u16 payload_len;
1724 	u32 lk_ahd;
1725 	struct htc_frame_hdr *htc_hdr = (struct htc_frame_hdr *)packet->buf;
1726 
1727 	if (n_lkahds != NULL)
1728 		*n_lkahds = 0;
1729 
1730 	/*
1731 	 * NOTE: we cannot assume the alignment of buf, so we use the safe
1732 	 * macros to retrieve 16 bit fields.
1733 	 */
1734 	payload_len = le16_to_cpu(get_unaligned(&htc_hdr->payld_len));
1735 
1736 	memcpy((u8 *)&lk_ahd, packet->buf, sizeof(lk_ahd));
1737 
1738 	if (packet->info.rx.rx_flags & HTC_RX_PKT_REFRESH_HDR) {
1739 		/*
1740 		 * Refresh the expected header and the actual length as it
1741 		 * was unknown when this packet was grabbed as part of the
1742 		 * bundle.
1743 		 */
1744 		packet->info.rx.exp_hdr = lk_ahd;
1745 		packet->act_len = payload_len + HTC_HDR_LENGTH;
1746 
1747 		/* validate the actual header that was refreshed  */
1748 		if (packet->act_len > packet->buf_len) {
1749 			ath6kl_err("refreshed hdr payload len (%d) in bundled recv is invalid (hdr: 0x%X)\n",
1750 				   payload_len, lk_ahd);
1751 			/*
1752 			 * Limit this to max buffer just to print out some
1753 			 * of the buffer.
1754 			 */
1755 			packet->act_len = min(packet->act_len, packet->buf_len);
1756 			status = -ENOMEM;
1757 			goto fail_rx;
1758 		}
1759 
1760 		if (packet->endpoint != htc_hdr->eid) {
1761 			ath6kl_err("refreshed hdr ep (%d) does not match expected ep (%d)\n",
1762 				   htc_hdr->eid, packet->endpoint);
1763 			status = -ENOMEM;
1764 			goto fail_rx;
1765 		}
1766 	}
1767 
1768 	if (lk_ahd != packet->info.rx.exp_hdr) {
1769 		ath6kl_err("%s(): lk_ahd mismatch! (pPkt:0x%p flags:0x%X)\n",
1770 			   __func__, packet, packet->info.rx.rx_flags);
1771 		ath6kl_dbg_dump(ATH6KL_DBG_HTC, "htc rx expected lk_ahd",
1772 				"", &packet->info.rx.exp_hdr, 4);
1773 		ath6kl_dbg_dump(ATH6KL_DBG_HTC, "htc rx current header",
1774 				"", (u8 *)&lk_ahd, sizeof(lk_ahd));
1775 		status = -ENOMEM;
1776 		goto fail_rx;
1777 	}
1778 
1779 	if (htc_hdr->flags & HTC_FLG_RX_TRAILER) {
1780 		if (htc_hdr->ctrl[0] < sizeof(struct htc_record_hdr) ||
1781 		    htc_hdr->ctrl[0] > payload_len) {
1782 			ath6kl_err("%s(): invalid hdr (payload len should be :%d, CB[0] is:%d)\n",
1783 				   __func__, payload_len, htc_hdr->ctrl[0]);
1784 			status = -ENOMEM;
1785 			goto fail_rx;
1786 		}
1787 
1788 		if (packet->info.rx.rx_flags & HTC_RX_PKT_IGNORE_LOOKAHEAD) {
1789 			next_lkahds = NULL;
1790 			n_lkahds = NULL;
1791 		}
1792 
1793 		status = htc_proc_trailer(target, packet->buf + HTC_HDR_LENGTH
1794 					  + payload_len - htc_hdr->ctrl[0],
1795 					  htc_hdr->ctrl[0], next_lkahds,
1796 					   n_lkahds, packet->endpoint);
1797 
1798 		if (status)
1799 			goto fail_rx;
1800 
1801 		packet->act_len -= htc_hdr->ctrl[0];
1802 	}
1803 
1804 	packet->buf += HTC_HDR_LENGTH;
1805 	packet->act_len -= HTC_HDR_LENGTH;
1806 
1807 fail_rx:
1808 	if (status)
1809 		ath6kl_dbg_dump(ATH6KL_DBG_HTC, "htc rx bad packet",
1810 				"", packet->buf, packet->act_len);
1811 
1812 	return status;
1813 }
1814 
ath6kl_htc_rx_complete(struct htc_endpoint * endpoint,struct htc_packet * packet)1815 static void ath6kl_htc_rx_complete(struct htc_endpoint *endpoint,
1816 				   struct htc_packet *packet)
1817 {
1818 		ath6kl_dbg(ATH6KL_DBG_HTC,
1819 			   "htc rx complete ep %d packet 0x%p\n",
1820 			   endpoint->eid, packet);
1821 		endpoint->ep_cb.rx(endpoint->target, packet);
1822 }
1823 
ath6kl_htc_rx_bundle(struct htc_target * target,struct list_head * rxq,struct list_head * sync_compq,int * n_pkt_fetched,bool part_bundle)1824 static int ath6kl_htc_rx_bundle(struct htc_target *target,
1825 				struct list_head *rxq,
1826 				struct list_head *sync_compq,
1827 				int *n_pkt_fetched, bool part_bundle)
1828 {
1829 	struct hif_scatter_req *scat_req;
1830 	struct htc_packet *packet;
1831 	int rem_space = target->max_rx_bndl_sz;
1832 	int n_scat_pkt, status = 0, i, len;
1833 
1834 	n_scat_pkt = get_queue_depth(rxq);
1835 	n_scat_pkt = min(n_scat_pkt, target->msg_per_bndl_max);
1836 
1837 	if ((get_queue_depth(rxq) - n_scat_pkt) > 0) {
1838 		/*
1839 		 * We were forced to split this bundle receive operation
1840 		 * all packets in this partial bundle must have their
1841 		 * lookaheads ignored.
1842 		 */
1843 		part_bundle = true;
1844 
1845 		/*
1846 		 * This would only happen if the target ignored our max
1847 		 * bundle limit.
1848 		 */
1849 		ath6kl_warn("%s(): partial bundle detected num:%d , %d\n",
1850 			    __func__, get_queue_depth(rxq), n_scat_pkt);
1851 	}
1852 
1853 	len = 0;
1854 
1855 	ath6kl_dbg(ATH6KL_DBG_HTC,
1856 		   "htc rx bundle depth %d pkts %d\n",
1857 		   get_queue_depth(rxq), n_scat_pkt);
1858 
1859 	scat_req = hif_scatter_req_get(target->dev->ar);
1860 
1861 	if (scat_req == NULL)
1862 		goto fail_rx_pkt;
1863 
1864 	for (i = 0; i < n_scat_pkt; i++) {
1865 		int pad_len;
1866 
1867 		packet = list_first_entry(rxq, struct htc_packet, list);
1868 		list_del(&packet->list);
1869 
1870 		pad_len = CALC_TXRX_PADDED_LEN(target,
1871 						   packet->act_len);
1872 
1873 		if ((rem_space - pad_len) < 0) {
1874 			list_add(&packet->list, rxq);
1875 			break;
1876 		}
1877 
1878 		rem_space -= pad_len;
1879 
1880 		if (part_bundle || (i < (n_scat_pkt - 1)))
1881 			/*
1882 			 * Packet 0..n-1 cannot be checked for look-aheads
1883 			 * since we are fetching a bundle the last packet
1884 			 * however can have it's lookahead used
1885 			 */
1886 			packet->info.rx.rx_flags |=
1887 			    HTC_RX_PKT_IGNORE_LOOKAHEAD;
1888 
1889 		/* NOTE: 1 HTC packet per scatter entry */
1890 		scat_req->scat_list[i].buf = packet->buf;
1891 		scat_req->scat_list[i].len = pad_len;
1892 
1893 		packet->info.rx.rx_flags |= HTC_RX_PKT_PART_OF_BUNDLE;
1894 
1895 		list_add_tail(&packet->list, sync_compq);
1896 
1897 		WARN_ON(!scat_req->scat_list[i].len);
1898 		len += scat_req->scat_list[i].len;
1899 	}
1900 
1901 	scat_req->len = len;
1902 	scat_req->scat_entries = i;
1903 
1904 	status = ath6kl_hif_submit_scat_req(target->dev, scat_req, true);
1905 
1906 	if (!status)
1907 		*n_pkt_fetched = i;
1908 
1909 	/* free scatter request */
1910 	hif_scatter_req_add(target->dev->ar, scat_req);
1911 
1912 fail_rx_pkt:
1913 
1914 	return status;
1915 }
1916 
ath6kl_htc_rx_process_packets(struct htc_target * target,struct list_head * comp_pktq,u32 lk_ahds[],int * n_lk_ahd)1917 static int ath6kl_htc_rx_process_packets(struct htc_target *target,
1918 					 struct list_head *comp_pktq,
1919 					 u32 lk_ahds[],
1920 					 int *n_lk_ahd)
1921 {
1922 	struct htc_packet *packet, *tmp_pkt;
1923 	struct htc_endpoint *ep;
1924 	int status = 0;
1925 
1926 	list_for_each_entry_safe(packet, tmp_pkt, comp_pktq, list) {
1927 		ep = &target->endpoint[packet->endpoint];
1928 
1929 		/* process header for each of the recv packet */
1930 		status = ath6kl_htc_rx_process_hdr(target, packet, lk_ahds,
1931 						   n_lk_ahd);
1932 		if (status)
1933 			return status;
1934 
1935 		list_del(&packet->list);
1936 
1937 		if (list_empty(comp_pktq)) {
1938 			/*
1939 			 * Last packet's more packet flag is set
1940 			 * based on the lookahead.
1941 			 */
1942 			if (*n_lk_ahd > 0)
1943 				ath6kl_htc_rx_set_indicate(lk_ahds[0],
1944 							   ep, packet);
1945 		} else
1946 			/*
1947 			 * Packets in a bundle automatically have
1948 			 * this flag set.
1949 			 */
1950 			packet->info.rx.indicat_flags |=
1951 				HTC_RX_FLAGS_INDICATE_MORE_PKTS;
1952 
1953 		ath6kl_htc_rx_update_stats(ep, *n_lk_ahd);
1954 
1955 		if (packet->info.rx.rx_flags & HTC_RX_PKT_PART_OF_BUNDLE)
1956 			ep->ep_st.rx_bundl += 1;
1957 
1958 		ath6kl_htc_rx_complete(ep, packet);
1959 	}
1960 
1961 	return status;
1962 }
1963 
ath6kl_htc_rx_fetch(struct htc_target * target,struct list_head * rx_pktq,struct list_head * comp_pktq)1964 static int ath6kl_htc_rx_fetch(struct htc_target *target,
1965 			       struct list_head *rx_pktq,
1966 			       struct list_head *comp_pktq)
1967 {
1968 	int fetched_pkts;
1969 	bool part_bundle = false;
1970 	int status = 0;
1971 	struct list_head tmp_rxq;
1972 	struct htc_packet *packet, *tmp_pkt;
1973 
1974 	/* now go fetch the list of HTC packets */
1975 	while (!list_empty(rx_pktq)) {
1976 		fetched_pkts = 0;
1977 
1978 		INIT_LIST_HEAD(&tmp_rxq);
1979 
1980 		if (target->rx_bndl_enable && (get_queue_depth(rx_pktq) > 1)) {
1981 			/*
1982 			 * There are enough packets to attempt a
1983 			 * bundle transfer and recv bundling is
1984 			 * allowed.
1985 			 */
1986 			status = ath6kl_htc_rx_bundle(target, rx_pktq,
1987 						      &tmp_rxq,
1988 						      &fetched_pkts,
1989 						      part_bundle);
1990 			if (status)
1991 				goto fail_rx;
1992 
1993 			if (!list_empty(rx_pktq))
1994 				part_bundle = true;
1995 
1996 			list_splice_tail_init(&tmp_rxq, comp_pktq);
1997 		}
1998 
1999 		if (!fetched_pkts) {
2000 
2001 			packet = list_first_entry(rx_pktq, struct htc_packet,
2002 						   list);
2003 
2004 			/* fully synchronous */
2005 			packet->completion = NULL;
2006 
2007 			if (!list_is_singular(rx_pktq))
2008 				/*
2009 				 * look_aheads in all packet
2010 				 * except the last one in the
2011 				 * bundle must be ignored
2012 				 */
2013 				packet->info.rx.rx_flags |=
2014 					HTC_RX_PKT_IGNORE_LOOKAHEAD;
2015 
2016 			/* go fetch the packet */
2017 			status = ath6kl_htc_rx_packet(target, packet,
2018 						      packet->act_len);
2019 
2020 			list_move_tail(&packet->list, &tmp_rxq);
2021 
2022 			if (status)
2023 				goto fail_rx;
2024 
2025 			list_splice_tail_init(&tmp_rxq, comp_pktq);
2026 		}
2027 	}
2028 
2029 	return 0;
2030 
2031 fail_rx:
2032 
2033 	/*
2034 	 * Cleanup any packets we allocated but didn't use to
2035 	 * actually fetch any packets.
2036 	 */
2037 
2038 	list_for_each_entry_safe(packet, tmp_pkt, rx_pktq, list) {
2039 		list_del(&packet->list);
2040 		htc_reclaim_rxbuf(target, packet,
2041 				&target->endpoint[packet->endpoint]);
2042 	}
2043 
2044 	list_for_each_entry_safe(packet, tmp_pkt, &tmp_rxq, list) {
2045 		list_del(&packet->list);
2046 		htc_reclaim_rxbuf(target, packet,
2047 				&target->endpoint[packet->endpoint]);
2048 	}
2049 
2050 	return status;
2051 }
2052 
ath6kl_htc_rxmsg_pending_handler(struct htc_target * target,u32 msg_look_ahead,int * num_pkts)2053 int ath6kl_htc_rxmsg_pending_handler(struct htc_target *target,
2054 				     u32 msg_look_ahead, int *num_pkts)
2055 {
2056 	struct htc_packet *packets, *tmp_pkt;
2057 	struct htc_endpoint *endpoint;
2058 	struct list_head rx_pktq, comp_pktq;
2059 	int status = 0;
2060 	u32 look_aheads[HTC_HOST_MAX_MSG_PER_BUNDLE];
2061 	int num_look_ahead = 1;
2062 	enum htc_endpoint_id id;
2063 	int n_fetched = 0;
2064 
2065 	*num_pkts = 0;
2066 
2067 	/*
2068 	 * On first entry copy the look_aheads into our temp array for
2069 	 * processing
2070 	 */
2071 	look_aheads[0] = msg_look_ahead;
2072 
2073 	while (true) {
2074 
2075 		/*
2076 		 * First lookahead sets the expected endpoint IDs for all
2077 		 * packets in a bundle.
2078 		 */
2079 		id = ((struct htc_frame_hdr *)&look_aheads[0])->eid;
2080 		endpoint = &target->endpoint[id];
2081 
2082 		if (id >= ENDPOINT_MAX) {
2083 			ath6kl_err("MsgPend, invalid endpoint in look-ahead: %d\n",
2084 				   id);
2085 			status = -ENOMEM;
2086 			break;
2087 		}
2088 
2089 		INIT_LIST_HEAD(&rx_pktq);
2090 		INIT_LIST_HEAD(&comp_pktq);
2091 
2092 		/*
2093 		 * Try to allocate as many HTC RX packets indicated by the
2094 		 * look_aheads.
2095 		 */
2096 		status = ath6kl_htc_rx_alloc(target, look_aheads,
2097 					     num_look_ahead, endpoint,
2098 					     &rx_pktq);
2099 		if (status)
2100 			break;
2101 
2102 		if (get_queue_depth(&rx_pktq) >= 2)
2103 			/*
2104 			 * A recv bundle was detected, force IRQ status
2105 			 * re-check again
2106 			 */
2107 			target->chk_irq_status_cnt = 1;
2108 
2109 		n_fetched += get_queue_depth(&rx_pktq);
2110 
2111 		num_look_ahead = 0;
2112 
2113 		status = ath6kl_htc_rx_fetch(target, &rx_pktq, &comp_pktq);
2114 
2115 		if (!status)
2116 			ath6kl_htc_rx_chk_water_mark(endpoint);
2117 
2118 		/* Process fetched packets */
2119 		status = ath6kl_htc_rx_process_packets(target, &comp_pktq,
2120 						       look_aheads,
2121 						       &num_look_ahead);
2122 
2123 		if (!num_look_ahead || status)
2124 			break;
2125 
2126 		/*
2127 		 * For SYNCH processing, if we get here, we are running
2128 		 * through the loop again due to a detected lookahead. Set
2129 		 * flag that we should re-check IRQ status registers again
2130 		 * before leaving IRQ processing, this can net better
2131 		 * performance in high throughput situations.
2132 		 */
2133 		target->chk_irq_status_cnt = 1;
2134 	}
2135 
2136 	if (status) {
2137 		ath6kl_err("failed to get pending recv messages: %d\n",
2138 			   status);
2139 
2140 		/* cleanup any packets in sync completion queue */
2141 		list_for_each_entry_safe(packets, tmp_pkt, &comp_pktq, list) {
2142 			list_del(&packets->list);
2143 			htc_reclaim_rxbuf(target, packets,
2144 					  &target->endpoint[packets->endpoint]);
2145 		}
2146 
2147 		if (target->htc_flags & HTC_OP_STATE_STOPPING) {
2148 			ath6kl_warn("host is going to stop blocking receiver for htc_stop\n");
2149 			ath6kl_hif_rx_control(target->dev, false);
2150 		}
2151 	}
2152 
2153 	/*
2154 	 * Before leaving, check to see if host ran out of buffers and
2155 	 * needs to stop the receiver.
2156 	 */
2157 	if (target->rx_st_flags & HTC_RECV_WAIT_BUFFERS) {
2158 		ath6kl_warn("host has no rx buffers blocking receiver to prevent overrun\n");
2159 		ath6kl_hif_rx_control(target->dev, false);
2160 	}
2161 	*num_pkts = n_fetched;
2162 
2163 	return status;
2164 }
2165 
2166 /*
2167  * Synchronously wait for a control message from the target,
2168  * This function is used at initialization time ONLY.  At init messages
2169  * on ENDPOINT 0 are expected.
2170  */
htc_wait_for_ctrl_msg(struct htc_target * target)2171 static struct htc_packet *htc_wait_for_ctrl_msg(struct htc_target *target)
2172 {
2173 	struct htc_packet *packet = NULL;
2174 	struct htc_frame_hdr *htc_hdr;
2175 	u32 look_ahead;
2176 
2177 	if (ath6kl_hif_poll_mboxmsg_rx(target->dev, &look_ahead,
2178 			       HTC_TARGET_RESPONSE_TIMEOUT))
2179 		return NULL;
2180 
2181 	ath6kl_dbg(ATH6KL_DBG_HTC,
2182 		"htc rx wait ctrl look_ahead 0x%X\n", look_ahead);
2183 
2184 	htc_hdr = (struct htc_frame_hdr *)&look_ahead;
2185 
2186 	if (htc_hdr->eid != ENDPOINT_0)
2187 		return NULL;
2188 
2189 	packet = htc_get_control_buf(target, false);
2190 
2191 	if (!packet)
2192 		return NULL;
2193 
2194 	packet->info.rx.rx_flags = 0;
2195 	packet->info.rx.exp_hdr = look_ahead;
2196 	packet->act_len = le16_to_cpu(htc_hdr->payld_len) + HTC_HDR_LENGTH;
2197 
2198 	if (packet->act_len > packet->buf_len)
2199 		goto fail_ctrl_rx;
2200 
2201 	/* we want synchronous operation */
2202 	packet->completion = NULL;
2203 
2204 	/* get the message from the device, this will block */
2205 	if (ath6kl_htc_rx_packet(target, packet, packet->act_len))
2206 		goto fail_ctrl_rx;
2207 
2208 	/* process receive header */
2209 	packet->status = ath6kl_htc_rx_process_hdr(target, packet, NULL, NULL);
2210 
2211 	if (packet->status) {
2212 		ath6kl_err("htc_wait_for_ctrl_msg, ath6kl_htc_rx_process_hdr failed (status = %d)\n",
2213 			   packet->status);
2214 		goto fail_ctrl_rx;
2215 	}
2216 
2217 	return packet;
2218 
2219 fail_ctrl_rx:
2220 	if (packet != NULL) {
2221 		htc_rxpkt_reset(packet);
2222 		reclaim_rx_ctrl_buf(target, packet);
2223 	}
2224 
2225 	return NULL;
2226 }
2227 
ath6kl_htc_add_rxbuf_multiple(struct htc_target * target,struct list_head * pkt_queue)2228 int ath6kl_htc_add_rxbuf_multiple(struct htc_target *target,
2229 				  struct list_head *pkt_queue)
2230 {
2231 	struct htc_endpoint *endpoint;
2232 	struct htc_packet *first_pkt;
2233 	bool rx_unblock = false;
2234 	int status = 0, depth;
2235 
2236 	if (list_empty(pkt_queue))
2237 		return -ENOMEM;
2238 
2239 	first_pkt = list_first_entry(pkt_queue, struct htc_packet, list);
2240 
2241 	if (first_pkt->endpoint >= ENDPOINT_MAX)
2242 		return status;
2243 
2244 	depth = get_queue_depth(pkt_queue);
2245 
2246 	ath6kl_dbg(ATH6KL_DBG_HTC,
2247 		"htc rx add multiple ep id %d cnt %d len %d\n",
2248 		first_pkt->endpoint, depth, first_pkt->buf_len);
2249 
2250 	endpoint = &target->endpoint[first_pkt->endpoint];
2251 
2252 	if (target->htc_flags & HTC_OP_STATE_STOPPING) {
2253 		struct htc_packet *packet, *tmp_pkt;
2254 
2255 		/* walk through queue and mark each one canceled */
2256 		list_for_each_entry_safe(packet, tmp_pkt, pkt_queue, list) {
2257 			packet->status = -ECANCELED;
2258 			list_del(&packet->list);
2259 			ath6kl_htc_rx_complete(endpoint, packet);
2260 		}
2261 
2262 		return status;
2263 	}
2264 
2265 	spin_lock_bh(&target->rx_lock);
2266 
2267 	list_splice_tail_init(pkt_queue, &endpoint->rx_bufq);
2268 
2269 	/* check if we are blocked waiting for a new buffer */
2270 	if (target->rx_st_flags & HTC_RECV_WAIT_BUFFERS) {
2271 		if (target->ep_waiting == first_pkt->endpoint) {
2272 			ath6kl_dbg(ATH6KL_DBG_HTC,
2273 				"htc rx blocked on ep %d, unblocking\n",
2274 				target->ep_waiting);
2275 			target->rx_st_flags &= ~HTC_RECV_WAIT_BUFFERS;
2276 			target->ep_waiting = ENDPOINT_MAX;
2277 			rx_unblock = true;
2278 		}
2279 	}
2280 
2281 	spin_unlock_bh(&target->rx_lock);
2282 
2283 	if (rx_unblock && !(target->htc_flags & HTC_OP_STATE_STOPPING))
2284 		/* TODO : implement a buffer threshold count? */
2285 		ath6kl_hif_rx_control(target->dev, true);
2286 
2287 	return status;
2288 }
2289 
ath6kl_htc_flush_rx_buf(struct htc_target * target)2290 void ath6kl_htc_flush_rx_buf(struct htc_target *target)
2291 {
2292 	struct htc_endpoint *endpoint;
2293 	struct htc_packet *packet, *tmp_pkt;
2294 	int i;
2295 
2296 	for (i = ENDPOINT_0; i < ENDPOINT_MAX; i++) {
2297 		endpoint = &target->endpoint[i];
2298 		if (!endpoint->svc_id)
2299 			/* not in use.. */
2300 			continue;
2301 
2302 		spin_lock_bh(&target->rx_lock);
2303 		list_for_each_entry_safe(packet, tmp_pkt,
2304 					 &endpoint->rx_bufq, list) {
2305 			list_del(&packet->list);
2306 			spin_unlock_bh(&target->rx_lock);
2307 			ath6kl_dbg(ATH6KL_DBG_HTC,
2308 				   "htc rx flush pkt 0x%p  len %d  ep %d\n",
2309 				   packet, packet->buf_len,
2310 				   packet->endpoint);
2311 			dev_kfree_skb(packet->pkt_cntxt);
2312 			spin_lock_bh(&target->rx_lock);
2313 		}
2314 		spin_unlock_bh(&target->rx_lock);
2315 	}
2316 }
2317 
ath6kl_htc_conn_service(struct htc_target * target,struct htc_service_connect_req * conn_req,struct htc_service_connect_resp * conn_resp)2318 int ath6kl_htc_conn_service(struct htc_target *target,
2319 			    struct htc_service_connect_req *conn_req,
2320 			    struct htc_service_connect_resp *conn_resp)
2321 {
2322 	struct htc_packet *rx_pkt = NULL;
2323 	struct htc_packet *tx_pkt = NULL;
2324 	struct htc_conn_service_resp *resp_msg;
2325 	struct htc_conn_service_msg *conn_msg;
2326 	struct htc_endpoint *endpoint;
2327 	enum htc_endpoint_id assigned_ep = ENDPOINT_MAX;
2328 	unsigned int max_msg_sz = 0;
2329 	int status = 0;
2330 
2331 	ath6kl_dbg(ATH6KL_DBG_HTC,
2332 		   "htc connect service target 0x%p service id 0x%x\n",
2333 		   target, conn_req->svc_id);
2334 
2335 	if (conn_req->svc_id == HTC_CTRL_RSVD_SVC) {
2336 		/* special case for pseudo control service */
2337 		assigned_ep = ENDPOINT_0;
2338 		max_msg_sz = HTC_MAX_CTRL_MSG_LEN;
2339 	} else {
2340 		/* allocate a packet to send to the target */
2341 		tx_pkt = htc_get_control_buf(target, true);
2342 
2343 		if (!tx_pkt)
2344 			return -ENOMEM;
2345 
2346 		conn_msg = (struct htc_conn_service_msg *)tx_pkt->buf;
2347 		memset(conn_msg, 0, sizeof(*conn_msg));
2348 		conn_msg->msg_id = cpu_to_le16(HTC_MSG_CONN_SVC_ID);
2349 		conn_msg->svc_id = cpu_to_le16(conn_req->svc_id);
2350 		conn_msg->conn_flags = cpu_to_le16(conn_req->conn_flags);
2351 
2352 		set_htc_pkt_info(tx_pkt, NULL, (u8 *) conn_msg,
2353 				 sizeof(*conn_msg) + conn_msg->svc_meta_len,
2354 				 ENDPOINT_0, HTC_SERVICE_TX_PACKET_TAG);
2355 
2356 		/* we want synchronous operation */
2357 		tx_pkt->completion = NULL;
2358 		ath6kl_htc_tx_prep_pkt(tx_pkt, 0, 0, 0);
2359 		status = ath6kl_htc_tx_issue(target, tx_pkt);
2360 
2361 		if (status)
2362 			goto fail_tx;
2363 
2364 		/* wait for response */
2365 		rx_pkt = htc_wait_for_ctrl_msg(target);
2366 
2367 		if (!rx_pkt) {
2368 			status = -ENOMEM;
2369 			goto fail_tx;
2370 		}
2371 
2372 		resp_msg = (struct htc_conn_service_resp *)rx_pkt->buf;
2373 
2374 		if ((le16_to_cpu(resp_msg->msg_id) != HTC_MSG_CONN_SVC_RESP_ID)
2375 		    || (rx_pkt->act_len < sizeof(*resp_msg))) {
2376 			status = -ENOMEM;
2377 			goto fail_tx;
2378 		}
2379 
2380 		conn_resp->resp_code = resp_msg->status;
2381 		/* check response status */
2382 		if (resp_msg->status != HTC_SERVICE_SUCCESS) {
2383 			ath6kl_err("target failed service 0x%X connect request (status:%d)\n",
2384 				   resp_msg->svc_id, resp_msg->status);
2385 			status = -ENOMEM;
2386 			goto fail_tx;
2387 		}
2388 
2389 		assigned_ep = (enum htc_endpoint_id)resp_msg->eid;
2390 		max_msg_sz = le16_to_cpu(resp_msg->max_msg_sz);
2391 	}
2392 
2393 	if (assigned_ep >= ENDPOINT_MAX || !max_msg_sz) {
2394 		status = -ENOMEM;
2395 		goto fail_tx;
2396 	}
2397 
2398 	endpoint = &target->endpoint[assigned_ep];
2399 	endpoint->eid = assigned_ep;
2400 	if (endpoint->svc_id) {
2401 		status = -ENOMEM;
2402 		goto fail_tx;
2403 	}
2404 
2405 	/* return assigned endpoint to caller */
2406 	conn_resp->endpoint = assigned_ep;
2407 	conn_resp->len_max = max_msg_sz;
2408 
2409 	/* setup the endpoint */
2410 
2411 	/* this marks the endpoint in use */
2412 	endpoint->svc_id = conn_req->svc_id;
2413 
2414 	endpoint->max_txq_depth = conn_req->max_txq_depth;
2415 	endpoint->len_max = max_msg_sz;
2416 	endpoint->ep_cb = conn_req->ep_cb;
2417 	endpoint->cred_dist.svc_id = conn_req->svc_id;
2418 	endpoint->cred_dist.htc_ep = endpoint;
2419 	endpoint->cred_dist.endpoint = assigned_ep;
2420 	endpoint->cred_dist.cred_sz = target->tgt_cred_sz;
2421 
2422 	if (conn_req->max_rxmsg_sz) {
2423 		/*
2424 		 * Override cred_per_msg calculation, this optimizes
2425 		 * the credit-low indications since the host will actually
2426 		 * issue smaller messages in the Send path.
2427 		 */
2428 		if (conn_req->max_rxmsg_sz > max_msg_sz) {
2429 			status = -ENOMEM;
2430 			goto fail_tx;
2431 		}
2432 		endpoint->cred_dist.cred_per_msg =
2433 		    conn_req->max_rxmsg_sz / target->tgt_cred_sz;
2434 	} else
2435 		endpoint->cred_dist.cred_per_msg =
2436 		    max_msg_sz / target->tgt_cred_sz;
2437 
2438 	if (!endpoint->cred_dist.cred_per_msg)
2439 		endpoint->cred_dist.cred_per_msg = 1;
2440 
2441 	/* save local connection flags */
2442 	endpoint->conn_flags = conn_req->flags;
2443 
2444 fail_tx:
2445 	if (tx_pkt)
2446 		htc_reclaim_txctrl_buf(target, tx_pkt);
2447 
2448 	if (rx_pkt) {
2449 		htc_rxpkt_reset(rx_pkt);
2450 		reclaim_rx_ctrl_buf(target, rx_pkt);
2451 	}
2452 
2453 	return status;
2454 }
2455 
reset_ep_state(struct htc_target * target)2456 static void reset_ep_state(struct htc_target *target)
2457 {
2458 	struct htc_endpoint *endpoint;
2459 	int i;
2460 
2461 	for (i = ENDPOINT_0; i < ENDPOINT_MAX; i++) {
2462 		endpoint = &target->endpoint[i];
2463 		memset(&endpoint->cred_dist, 0, sizeof(endpoint->cred_dist));
2464 		endpoint->svc_id = 0;
2465 		endpoint->len_max = 0;
2466 		endpoint->max_txq_depth = 0;
2467 		memset(&endpoint->ep_st, 0,
2468 		       sizeof(endpoint->ep_st));
2469 		INIT_LIST_HEAD(&endpoint->rx_bufq);
2470 		INIT_LIST_HEAD(&endpoint->txq);
2471 		endpoint->target = target;
2472 	}
2473 
2474 	/* reset distribution list */
2475 	/* FIXME: free existing entries */
2476 	INIT_LIST_HEAD(&target->cred_dist_list);
2477 }
2478 
ath6kl_htc_get_rxbuf_num(struct htc_target * target,enum htc_endpoint_id endpoint)2479 int ath6kl_htc_get_rxbuf_num(struct htc_target *target,
2480 			     enum htc_endpoint_id endpoint)
2481 {
2482 	int num;
2483 
2484 	spin_lock_bh(&target->rx_lock);
2485 	num = get_queue_depth(&(target->endpoint[endpoint].rx_bufq));
2486 	spin_unlock_bh(&target->rx_lock);
2487 	return num;
2488 }
2489 
htc_setup_msg_bndl(struct htc_target * target)2490 static void htc_setup_msg_bndl(struct htc_target *target)
2491 {
2492 	/* limit what HTC can handle */
2493 	target->msg_per_bndl_max = min(HTC_HOST_MAX_MSG_PER_BUNDLE,
2494 				       target->msg_per_bndl_max);
2495 
2496 	if (ath6kl_hif_enable_scatter(target->dev->ar)) {
2497 		target->msg_per_bndl_max = 0;
2498 		return;
2499 	}
2500 
2501 	/* limit bundle what the device layer can handle */
2502 	target->msg_per_bndl_max = min(target->max_scat_entries,
2503 				       target->msg_per_bndl_max);
2504 
2505 	ath6kl_dbg(ATH6KL_DBG_BOOT,
2506 		   "htc bundling allowed msg_per_bndl_max %d\n",
2507 		   target->msg_per_bndl_max);
2508 
2509 	/* Max rx bundle size is limited by the max tx bundle size */
2510 	target->max_rx_bndl_sz = target->max_xfer_szper_scatreq;
2511 	/* Max tx bundle size if limited by the extended mbox address range */
2512 	target->max_tx_bndl_sz = min(HIF_MBOX0_EXT_WIDTH,
2513 				     target->max_xfer_szper_scatreq);
2514 
2515 	ath6kl_dbg(ATH6KL_DBG_BOOT, "htc max_rx_bndl_sz %d max_tx_bndl_sz %d\n",
2516 		   target->max_rx_bndl_sz, target->max_tx_bndl_sz);
2517 
2518 	if (target->max_tx_bndl_sz)
2519 		target->tx_bndl_enable = true;
2520 
2521 	if (target->max_rx_bndl_sz)
2522 		target->rx_bndl_enable = true;
2523 
2524 	if ((target->tgt_cred_sz % target->block_sz) != 0) {
2525 		ath6kl_warn("credit size: %d is not block aligned! Disabling send bundling\n",
2526 			    target->tgt_cred_sz);
2527 
2528 		/*
2529 		 * Disallow send bundling since the credit size is
2530 		 * not aligned to a block size the I/O block
2531 		 * padding will spill into the next credit buffer
2532 		 * which is fatal.
2533 		 */
2534 		target->tx_bndl_enable = false;
2535 	}
2536 }
2537 
ath6kl_htc_wait_target(struct htc_target * target)2538 int ath6kl_htc_wait_target(struct htc_target *target)
2539 {
2540 	struct htc_packet *packet = NULL;
2541 	struct htc_ready_ext_msg *rdy_msg;
2542 	struct htc_service_connect_req connect;
2543 	struct htc_service_connect_resp resp;
2544 	int status;
2545 
2546 	/* we should be getting 1 control message that the target is ready */
2547 	packet = htc_wait_for_ctrl_msg(target);
2548 
2549 	if (!packet)
2550 		return -ENOMEM;
2551 
2552 	/* we controlled the buffer creation so it's properly aligned */
2553 	rdy_msg = (struct htc_ready_ext_msg *)packet->buf;
2554 
2555 	if ((le16_to_cpu(rdy_msg->ver2_0_info.msg_id) != HTC_MSG_READY_ID) ||
2556 	    (packet->act_len < sizeof(struct htc_ready_msg))) {
2557 		status = -ENOMEM;
2558 		goto fail_wait_target;
2559 	}
2560 
2561 	if (!rdy_msg->ver2_0_info.cred_cnt || !rdy_msg->ver2_0_info.cred_sz) {
2562 		status = -ENOMEM;
2563 		goto fail_wait_target;
2564 	}
2565 
2566 	target->tgt_creds = le16_to_cpu(rdy_msg->ver2_0_info.cred_cnt);
2567 	target->tgt_cred_sz = le16_to_cpu(rdy_msg->ver2_0_info.cred_sz);
2568 
2569 	ath6kl_dbg(ATH6KL_DBG_BOOT,
2570 		   "htc target ready credits %d size %d\n",
2571 		   target->tgt_creds, target->tgt_cred_sz);
2572 
2573 	/* check if this is an extended ready message */
2574 	if (packet->act_len >= sizeof(struct htc_ready_ext_msg)) {
2575 		/* this is an extended message */
2576 		target->htc_tgt_ver = rdy_msg->htc_ver;
2577 		target->msg_per_bndl_max = rdy_msg->msg_per_htc_bndl;
2578 	} else {
2579 		/* legacy */
2580 		target->htc_tgt_ver = HTC_VERSION_2P0;
2581 		target->msg_per_bndl_max = 0;
2582 	}
2583 
2584 	ath6kl_dbg(ATH6KL_DBG_BOOT, "htc using protocol %s (%d)\n",
2585 		  (target->htc_tgt_ver == HTC_VERSION_2P0) ? "2.0" : ">= 2.1",
2586 		  target->htc_tgt_ver);
2587 
2588 	if (target->msg_per_bndl_max > 0)
2589 		htc_setup_msg_bndl(target);
2590 
2591 	/* setup our pseudo HTC control endpoint connection */
2592 	memset(&connect, 0, sizeof(connect));
2593 	memset(&resp, 0, sizeof(resp));
2594 	connect.ep_cb.rx = htc_ctrl_rx;
2595 	connect.ep_cb.rx_refill = NULL;
2596 	connect.ep_cb.tx_full = NULL;
2597 	connect.max_txq_depth = NUM_CONTROL_BUFFERS;
2598 	connect.svc_id = HTC_CTRL_RSVD_SVC;
2599 
2600 	/* connect fake service */
2601 	status = ath6kl_htc_conn_service((void *)target, &connect, &resp);
2602 
2603 	if (status)
2604 		/*
2605 		 * FIXME: this call doesn't make sense, the caller should
2606 		 * call ath6kl_htc_cleanup() when it wants remove htc
2607 		 */
2608 		ath6kl_hif_cleanup_scatter(target->dev->ar);
2609 
2610 fail_wait_target:
2611 	if (packet) {
2612 		htc_rxpkt_reset(packet);
2613 		reclaim_rx_ctrl_buf(target, packet);
2614 	}
2615 
2616 	return status;
2617 }
2618 
2619 /*
2620  * Start HTC, enable interrupts and let the target know
2621  * host has finished setup.
2622  */
ath6kl_htc_start(struct htc_target * target)2623 int ath6kl_htc_start(struct htc_target *target)
2624 {
2625 	struct htc_packet *packet;
2626 	int status;
2627 
2628 	memset(&target->dev->irq_proc_reg, 0,
2629 	       sizeof(target->dev->irq_proc_reg));
2630 
2631 	/* Disable interrupts at the chip level */
2632 	ath6kl_hif_disable_intrs(target->dev);
2633 
2634 	target->htc_flags = 0;
2635 	target->rx_st_flags = 0;
2636 
2637 	/* Push control receive buffers into htc control endpoint */
2638 	while ((packet = htc_get_control_buf(target, false)) != NULL) {
2639 		status = htc_add_rxbuf(target, packet);
2640 		if (status)
2641 			return status;
2642 	}
2643 
2644 	/* NOTE: the first entry in the distribution list is ENDPOINT_0 */
2645 	ath6kl_credit_init(target->credit_info, &target->cred_dist_list,
2646 			   target->tgt_creds);
2647 
2648 	dump_cred_dist_stats(target);
2649 
2650 	/* Indicate to the target of the setup completion */
2651 	status = htc_setup_tx_complete(target);
2652 
2653 	if (status)
2654 		return status;
2655 
2656 	/* unmask interrupts */
2657 	status = ath6kl_hif_unmask_intrs(target->dev);
2658 
2659 	if (status)
2660 		ath6kl_htc_stop(target);
2661 
2662 	return status;
2663 }
2664 
ath6kl_htc_reset(struct htc_target * target)2665 static int ath6kl_htc_reset(struct htc_target *target)
2666 {
2667 	u32 block_size, ctrl_bufsz;
2668 	struct htc_packet *packet;
2669 	int i;
2670 
2671 	reset_ep_state(target);
2672 
2673 	block_size = target->dev->ar->mbox_info.block_size;
2674 
2675 	ctrl_bufsz = (block_size > HTC_MAX_CTRL_MSG_LEN) ?
2676 		      (block_size + HTC_HDR_LENGTH) :
2677 		      (HTC_MAX_CTRL_MSG_LEN + HTC_HDR_LENGTH);
2678 
2679 	for (i = 0; i < NUM_CONTROL_BUFFERS; i++) {
2680 		packet = kzalloc(sizeof(*packet), GFP_KERNEL);
2681 		if (!packet)
2682 			return -ENOMEM;
2683 
2684 		packet->buf_start = kzalloc(ctrl_bufsz, GFP_KERNEL);
2685 		if (!packet->buf_start) {
2686 			kfree(packet);
2687 			return -ENOMEM;
2688 		}
2689 
2690 		packet->buf_len = ctrl_bufsz;
2691 		if (i < NUM_CONTROL_RX_BUFFERS) {
2692 			packet->act_len = 0;
2693 			packet->buf = packet->buf_start;
2694 			packet->endpoint = ENDPOINT_0;
2695 			list_add_tail(&packet->list, &target->free_ctrl_rxbuf);
2696 		} else
2697 			list_add_tail(&packet->list, &target->free_ctrl_txbuf);
2698 	}
2699 
2700 	return 0;
2701 }
2702 
2703 /* htc_stop: stop interrupt reception, and flush all queued buffers */
ath6kl_htc_stop(struct htc_target * target)2704 void ath6kl_htc_stop(struct htc_target *target)
2705 {
2706 	spin_lock_bh(&target->htc_lock);
2707 	target->htc_flags |= HTC_OP_STATE_STOPPING;
2708 	spin_unlock_bh(&target->htc_lock);
2709 
2710 	/*
2711 	 * Masking interrupts is a synchronous operation, when this
2712 	 * function returns all pending HIF I/O has completed, we can
2713 	 * safely flush the queues.
2714 	 */
2715 	ath6kl_hif_mask_intrs(target->dev);
2716 
2717 	ath6kl_htc_flush_txep_all(target);
2718 
2719 	ath6kl_htc_flush_rx_buf(target);
2720 
2721 	ath6kl_htc_reset(target);
2722 }
2723 
ath6kl_htc_create(struct ath6kl * ar)2724 void *ath6kl_htc_create(struct ath6kl *ar)
2725 {
2726 	struct htc_target *target = NULL;
2727 	int status = 0;
2728 
2729 	target = kzalloc(sizeof(*target), GFP_KERNEL);
2730 	if (!target) {
2731 		ath6kl_err("unable to allocate memory\n");
2732 		return NULL;
2733 	}
2734 
2735 	target->dev = kzalloc(sizeof(*target->dev), GFP_KERNEL);
2736 	if (!target->dev) {
2737 		ath6kl_err("unable to allocate memory\n");
2738 		status = -ENOMEM;
2739 		goto err_htc_cleanup;
2740 	}
2741 
2742 	spin_lock_init(&target->htc_lock);
2743 	spin_lock_init(&target->rx_lock);
2744 	spin_lock_init(&target->tx_lock);
2745 
2746 	INIT_LIST_HEAD(&target->free_ctrl_txbuf);
2747 	INIT_LIST_HEAD(&target->free_ctrl_rxbuf);
2748 	INIT_LIST_HEAD(&target->cred_dist_list);
2749 
2750 	target->dev->ar = ar;
2751 	target->dev->htc_cnxt = target;
2752 	target->ep_waiting = ENDPOINT_MAX;
2753 
2754 	status = ath6kl_hif_setup(target->dev);
2755 	if (status)
2756 		goto err_htc_cleanup;
2757 
2758 	status = ath6kl_htc_reset(target);
2759 	if (status)
2760 		goto err_htc_cleanup;
2761 
2762 	return target;
2763 
2764 err_htc_cleanup:
2765 	ath6kl_htc_cleanup(target);
2766 
2767 	return NULL;
2768 }
2769 
2770 /* cleanup the HTC instance */
ath6kl_htc_cleanup(struct htc_target * target)2771 void ath6kl_htc_cleanup(struct htc_target *target)
2772 {
2773 	struct htc_packet *packet, *tmp_packet;
2774 
2775 	ath6kl_hif_cleanup_scatter(target->dev->ar);
2776 
2777 	list_for_each_entry_safe(packet, tmp_packet,
2778 			&target->free_ctrl_txbuf, list) {
2779 		list_del(&packet->list);
2780 		kfree(packet->buf_start);
2781 		kfree(packet);
2782 	}
2783 
2784 	list_for_each_entry_safe(packet, tmp_packet,
2785 			&target->free_ctrl_rxbuf, list) {
2786 		list_del(&packet->list);
2787 		kfree(packet->buf_start);
2788 		kfree(packet);
2789 	}
2790 
2791 	kfree(target->dev);
2792 	kfree(target);
2793 }
2794