xref: /openbmc/linux/drivers/net/wireless/ath/ath10k/htc.c (revision e23feb16)
1 /*
2  * Copyright (c) 2005-2011 Atheros Communications Inc.
3  * Copyright (c) 2011-2013 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 
22 /********/
23 /* Send */
24 /********/
25 
26 static inline void ath10k_htc_send_complete_check(struct ath10k_htc_ep *ep,
27 						  int force)
28 {
29 	/*
30 	 * Check whether HIF has any prior sends that have finished,
31 	 * have not had the post-processing done.
32 	 */
33 	ath10k_hif_send_complete_check(ep->htc->ar, ep->ul_pipe_id, force);
34 }
35 
36 static void ath10k_htc_control_tx_complete(struct ath10k *ar,
37 					   struct sk_buff *skb)
38 {
39 	kfree_skb(skb);
40 }
41 
42 static struct sk_buff *ath10k_htc_build_tx_ctrl_skb(void *ar)
43 {
44 	struct sk_buff *skb;
45 	struct ath10k_skb_cb *skb_cb;
46 
47 	skb = dev_alloc_skb(ATH10K_HTC_CONTROL_BUFFER_SIZE);
48 	if (!skb) {
49 		ath10k_warn("Unable to allocate ctrl skb\n");
50 		return NULL;
51 	}
52 
53 	skb_reserve(skb, 20); /* FIXME: why 20 bytes? */
54 	WARN_ONCE((unsigned long)skb->data & 3, "unaligned skb");
55 
56 	skb_cb = ATH10K_SKB_CB(skb);
57 	memset(skb_cb, 0, sizeof(*skb_cb));
58 
59 	ath10k_dbg(ATH10K_DBG_HTC, "%s: skb %p\n", __func__, skb);
60 	return skb;
61 }
62 
63 static inline void ath10k_htc_restore_tx_skb(struct ath10k_htc *htc,
64 					     struct sk_buff *skb)
65 {
66 	ath10k_skb_unmap(htc->ar->dev, skb);
67 	skb_pull(skb, sizeof(struct ath10k_htc_hdr));
68 }
69 
70 static void ath10k_htc_notify_tx_completion(struct ath10k_htc_ep *ep,
71 					    struct sk_buff *skb)
72 {
73 	ath10k_dbg(ATH10K_DBG_HTC, "%s: ep %d skb %p\n", __func__,
74 		   ep->eid, skb);
75 
76 	ath10k_htc_restore_tx_skb(ep->htc, skb);
77 
78 	if (!ep->ep_ops.ep_tx_complete) {
79 		ath10k_warn("no tx handler for eid %d\n", ep->eid);
80 		dev_kfree_skb_any(skb);
81 		return;
82 	}
83 
84 	ep->ep_ops.ep_tx_complete(ep->htc->ar, skb);
85 }
86 
87 /* assumes tx_lock is held */
88 static bool ath10k_htc_ep_need_credit_update(struct ath10k_htc_ep *ep)
89 {
90 	if (!ep->tx_credit_flow_enabled)
91 		return false;
92 	if (ep->tx_credits >= ep->tx_credits_per_max_message)
93 		return false;
94 
95 	ath10k_dbg(ATH10K_DBG_HTC, "HTC: endpoint %d needs credit update\n",
96 		   ep->eid);
97 	return true;
98 }
99 
100 static void ath10k_htc_prepare_tx_skb(struct ath10k_htc_ep *ep,
101 				      struct sk_buff *skb)
102 {
103 	struct ath10k_htc_hdr *hdr;
104 
105 	hdr = (struct ath10k_htc_hdr *)skb->data;
106 	memset(hdr, 0, sizeof(*hdr));
107 
108 	hdr->eid = ep->eid;
109 	hdr->len = __cpu_to_le16(skb->len - sizeof(*hdr));
110 
111 	spin_lock_bh(&ep->htc->tx_lock);
112 	hdr->seq_no = ep->seq_no++;
113 
114 	if (ath10k_htc_ep_need_credit_update(ep))
115 		hdr->flags |= ATH10K_HTC_FLAG_NEED_CREDIT_UPDATE;
116 
117 	spin_unlock_bh(&ep->htc->tx_lock);
118 }
119 
120 static int ath10k_htc_issue_skb(struct ath10k_htc *htc,
121 				struct ath10k_htc_ep *ep,
122 				struct sk_buff *skb,
123 				u8 credits)
124 {
125 	struct ath10k_skb_cb *skb_cb = ATH10K_SKB_CB(skb);
126 	int ret;
127 
128 	ath10k_dbg(ATH10K_DBG_HTC, "%s: ep %d skb %p\n", __func__,
129 		   ep->eid, skb);
130 
131 	ath10k_htc_prepare_tx_skb(ep, skb);
132 
133 	ret = ath10k_skb_map(htc->ar->dev, skb);
134 	if (ret)
135 		goto err;
136 
137 	ret = ath10k_hif_send_head(htc->ar,
138 				   ep->ul_pipe_id,
139 				   ep->eid,
140 				   skb->len,
141 				   skb);
142 	if (unlikely(ret))
143 		goto err;
144 
145 	return 0;
146 err:
147 	ath10k_warn("HTC issue failed: %d\n", ret);
148 
149 	spin_lock_bh(&htc->tx_lock);
150 	ep->tx_credits += credits;
151 	spin_unlock_bh(&htc->tx_lock);
152 
153 	/* this is the simplest way to handle out-of-resources for non-credit
154 	 * based endpoints. credit based endpoints can still get -ENOSR, but
155 	 * this is highly unlikely as credit reservation should prevent that */
156 	if (ret == -ENOSR) {
157 		spin_lock_bh(&htc->tx_lock);
158 		__skb_queue_head(&ep->tx_queue, skb);
159 		spin_unlock_bh(&htc->tx_lock);
160 
161 		return ret;
162 	}
163 
164 	skb_cb->is_aborted = true;
165 	ath10k_htc_notify_tx_completion(ep, skb);
166 
167 	return ret;
168 }
169 
170 static struct sk_buff *ath10k_htc_get_skb_credit_based(struct ath10k_htc *htc,
171 						       struct ath10k_htc_ep *ep,
172 						       u8 *credits)
173 {
174 	struct sk_buff *skb;
175 	struct ath10k_skb_cb *skb_cb;
176 	int credits_required;
177 	int remainder;
178 	unsigned int transfer_len;
179 
180 	lockdep_assert_held(&htc->tx_lock);
181 
182 	skb = __skb_dequeue(&ep->tx_queue);
183 	if (!skb)
184 		return NULL;
185 
186 	skb_cb = ATH10K_SKB_CB(skb);
187 	transfer_len = skb->len;
188 
189 	if (likely(transfer_len <= htc->target_credit_size)) {
190 		credits_required = 1;
191 	} else {
192 		/* figure out how many credits this message requires */
193 		credits_required = transfer_len / htc->target_credit_size;
194 		remainder = transfer_len % htc->target_credit_size;
195 
196 		if (remainder)
197 			credits_required++;
198 	}
199 
200 	ath10k_dbg(ATH10K_DBG_HTC, "Credits required %d got %d\n",
201 		   credits_required, ep->tx_credits);
202 
203 	if (ep->tx_credits < credits_required) {
204 		__skb_queue_head(&ep->tx_queue, skb);
205 		return NULL;
206 	}
207 
208 	ep->tx_credits -= credits_required;
209 	*credits = credits_required;
210 	return skb;
211 }
212 
213 static void ath10k_htc_send_work(struct work_struct *work)
214 {
215 	struct ath10k_htc_ep *ep = container_of(work,
216 					struct ath10k_htc_ep, send_work);
217 	struct ath10k_htc *htc = ep->htc;
218 	struct sk_buff *skb;
219 	u8 credits = 0;
220 	int ret;
221 
222 	while (true) {
223 		if (ep->ul_is_polled)
224 			ath10k_htc_send_complete_check(ep, 0);
225 
226 		spin_lock_bh(&htc->tx_lock);
227 		if (ep->tx_credit_flow_enabled)
228 			skb = ath10k_htc_get_skb_credit_based(htc, ep,
229 							      &credits);
230 		else
231 			skb = __skb_dequeue(&ep->tx_queue);
232 		spin_unlock_bh(&htc->tx_lock);
233 
234 		if (!skb)
235 			break;
236 
237 		ret = ath10k_htc_issue_skb(htc, ep, skb, credits);
238 		if (ret == -ENOSR)
239 			break;
240 	}
241 }
242 
243 int ath10k_htc_send(struct ath10k_htc *htc,
244 		    enum ath10k_htc_ep_id eid,
245 		    struct sk_buff *skb)
246 {
247 	struct ath10k_htc_ep *ep = &htc->endpoint[eid];
248 
249 	if (htc->ar->state == ATH10K_STATE_WEDGED)
250 		return -ECOMM;
251 
252 	if (eid >= ATH10K_HTC_EP_COUNT) {
253 		ath10k_warn("Invalid endpoint id: %d\n", eid);
254 		return -ENOENT;
255 	}
256 
257 	spin_lock_bh(&htc->tx_lock);
258 	if (htc->stopped) {
259 		spin_unlock_bh(&htc->tx_lock);
260 		return -ESHUTDOWN;
261 	}
262 
263 	__skb_queue_tail(&ep->tx_queue, skb);
264 	skb_push(skb, sizeof(struct ath10k_htc_hdr));
265 	spin_unlock_bh(&htc->tx_lock);
266 
267 	queue_work(htc->ar->workqueue, &ep->send_work);
268 	return 0;
269 }
270 
271 static int ath10k_htc_tx_completion_handler(struct ath10k *ar,
272 					    struct sk_buff *skb,
273 					    unsigned int eid)
274 {
275 	struct ath10k_htc *htc = &ar->htc;
276 	struct ath10k_htc_ep *ep = &htc->endpoint[eid];
277 
278 	ath10k_htc_notify_tx_completion(ep, skb);
279 	/* the skb now belongs to the completion handler */
280 
281 	/* note: when using TX credit flow, the re-checking of queues happens
282 	 * when credits flow back from the target.  in the non-TX credit case,
283 	 * we recheck after the packet completes */
284 	spin_lock_bh(&htc->tx_lock);
285 	if (!ep->tx_credit_flow_enabled && !htc->stopped)
286 		queue_work(ar->workqueue, &ep->send_work);
287 	spin_unlock_bh(&htc->tx_lock);
288 
289 	return 0;
290 }
291 
292 /* flush endpoint TX queue */
293 static void ath10k_htc_flush_endpoint_tx(struct ath10k_htc *htc,
294 					 struct ath10k_htc_ep *ep)
295 {
296 	struct sk_buff *skb;
297 	struct ath10k_skb_cb *skb_cb;
298 
299 	spin_lock_bh(&htc->tx_lock);
300 	for (;;) {
301 		skb = __skb_dequeue(&ep->tx_queue);
302 		if (!skb)
303 			break;
304 
305 		skb_cb = ATH10K_SKB_CB(skb);
306 		skb_cb->is_aborted = true;
307 		ath10k_htc_notify_tx_completion(ep, skb);
308 	}
309 	spin_unlock_bh(&htc->tx_lock);
310 
311 	cancel_work_sync(&ep->send_work);
312 }
313 
314 /***********/
315 /* Receive */
316 /***********/
317 
318 static void
319 ath10k_htc_process_credit_report(struct ath10k_htc *htc,
320 				 const struct ath10k_htc_credit_report *report,
321 				 int len,
322 				 enum ath10k_htc_ep_id eid)
323 {
324 	struct ath10k_htc_ep *ep;
325 	int i, n_reports;
326 
327 	if (len % sizeof(*report))
328 		ath10k_warn("Uneven credit report len %d", len);
329 
330 	n_reports = len / sizeof(*report);
331 
332 	spin_lock_bh(&htc->tx_lock);
333 	for (i = 0; i < n_reports; i++, report++) {
334 		if (report->eid >= ATH10K_HTC_EP_COUNT)
335 			break;
336 
337 		ath10k_dbg(ATH10K_DBG_HTC, "ep %d got %d credits\n",
338 			   report->eid, report->credits);
339 
340 		ep = &htc->endpoint[report->eid];
341 		ep->tx_credits += report->credits;
342 
343 		if (ep->tx_credits && !skb_queue_empty(&ep->tx_queue))
344 			queue_work(htc->ar->workqueue, &ep->send_work);
345 	}
346 	spin_unlock_bh(&htc->tx_lock);
347 }
348 
349 static int ath10k_htc_process_trailer(struct ath10k_htc *htc,
350 				      u8 *buffer,
351 				      int length,
352 				      enum ath10k_htc_ep_id src_eid)
353 {
354 	int status = 0;
355 	struct ath10k_htc_record *record;
356 	u8 *orig_buffer;
357 	int orig_length;
358 	size_t len;
359 
360 	orig_buffer = buffer;
361 	orig_length = length;
362 
363 	while (length > 0) {
364 		record = (struct ath10k_htc_record *)buffer;
365 
366 		if (length < sizeof(record->hdr)) {
367 			status = -EINVAL;
368 			break;
369 		}
370 
371 		if (record->hdr.len > length) {
372 			/* no room left in buffer for record */
373 			ath10k_warn("Invalid record length: %d\n",
374 				    record->hdr.len);
375 			status = -EINVAL;
376 			break;
377 		}
378 
379 		switch (record->hdr.id) {
380 		case ATH10K_HTC_RECORD_CREDITS:
381 			len = sizeof(struct ath10k_htc_credit_report);
382 			if (record->hdr.len < len) {
383 				ath10k_warn("Credit report too long\n");
384 				status = -EINVAL;
385 				break;
386 			}
387 			ath10k_htc_process_credit_report(htc,
388 							 record->credit_report,
389 							 record->hdr.len,
390 							 src_eid);
391 			break;
392 		default:
393 			ath10k_warn("Unhandled record: id:%d length:%d\n",
394 				    record->hdr.id, record->hdr.len);
395 			break;
396 		}
397 
398 		if (status)
399 			break;
400 
401 		/* multiple records may be present in a trailer */
402 		buffer += sizeof(record->hdr) + record->hdr.len;
403 		length -= sizeof(record->hdr) + record->hdr.len;
404 	}
405 
406 	if (status)
407 		ath10k_dbg_dump(ATH10K_DBG_HTC, "htc rx bad trailer", "",
408 				orig_buffer, orig_length);
409 
410 	return status;
411 }
412 
413 static int ath10k_htc_rx_completion_handler(struct ath10k *ar,
414 					    struct sk_buff *skb,
415 					    u8 pipe_id)
416 {
417 	int status = 0;
418 	struct ath10k_htc *htc = &ar->htc;
419 	struct ath10k_htc_hdr *hdr;
420 	struct ath10k_htc_ep *ep;
421 	u16 payload_len;
422 	u32 trailer_len = 0;
423 	size_t min_len;
424 	u8 eid;
425 	bool trailer_present;
426 
427 	hdr = (struct ath10k_htc_hdr *)skb->data;
428 	skb_pull(skb, sizeof(*hdr));
429 
430 	eid = hdr->eid;
431 
432 	if (eid >= ATH10K_HTC_EP_COUNT) {
433 		ath10k_warn("HTC Rx: invalid eid %d\n", eid);
434 		ath10k_dbg_dump(ATH10K_DBG_HTC, "htc bad header", "",
435 				hdr, sizeof(*hdr));
436 		status = -EINVAL;
437 		goto out;
438 	}
439 
440 	ep = &htc->endpoint[eid];
441 
442 	/*
443 	 * If this endpoint that received a message from the target has
444 	 * a to-target HIF pipe whose send completions are polled rather
445 	 * than interrupt-driven, this is a good point to ask HIF to check
446 	 * whether it has any completed sends to handle.
447 	 */
448 	if (ep->ul_is_polled)
449 		ath10k_htc_send_complete_check(ep, 1);
450 
451 	payload_len = __le16_to_cpu(hdr->len);
452 
453 	if (payload_len + sizeof(*hdr) > ATH10K_HTC_MAX_LEN) {
454 		ath10k_warn("HTC rx frame too long, len: %zu\n",
455 			    payload_len + sizeof(*hdr));
456 		ath10k_dbg_dump(ATH10K_DBG_HTC, "htc bad rx pkt len", "",
457 				hdr, sizeof(*hdr));
458 		status = -EINVAL;
459 		goto out;
460 	}
461 
462 	if (skb->len < payload_len) {
463 		ath10k_dbg(ATH10K_DBG_HTC,
464 			   "HTC Rx: insufficient length, got %d, expected %d\n",
465 			   skb->len, payload_len);
466 		ath10k_dbg_dump(ATH10K_DBG_HTC, "htc bad rx pkt len",
467 				"", hdr, sizeof(*hdr));
468 		status = -EINVAL;
469 		goto out;
470 	}
471 
472 	/* get flags to check for trailer */
473 	trailer_present = hdr->flags & ATH10K_HTC_FLAG_TRAILER_PRESENT;
474 	if (trailer_present) {
475 		u8 *trailer;
476 
477 		trailer_len = hdr->trailer_len;
478 		min_len = sizeof(struct ath10k_ath10k_htc_record_hdr);
479 
480 		if ((trailer_len < min_len) ||
481 		    (trailer_len > payload_len)) {
482 			ath10k_warn("Invalid trailer length: %d\n",
483 				    trailer_len);
484 			status = -EPROTO;
485 			goto out;
486 		}
487 
488 		trailer = (u8 *)hdr;
489 		trailer += sizeof(*hdr);
490 		trailer += payload_len;
491 		trailer -= trailer_len;
492 		status = ath10k_htc_process_trailer(htc, trailer,
493 						    trailer_len, hdr->eid);
494 		if (status)
495 			goto out;
496 
497 		skb_trim(skb, skb->len - trailer_len);
498 	}
499 
500 	if (((int)payload_len - (int)trailer_len) <= 0)
501 		/* zero length packet with trailer data, just drop these */
502 		goto out;
503 
504 	if (eid == ATH10K_HTC_EP_0) {
505 		struct ath10k_htc_msg *msg = (struct ath10k_htc_msg *)skb->data;
506 
507 		switch (__le16_to_cpu(msg->hdr.message_id)) {
508 		default:
509 			/* handle HTC control message */
510 			if (completion_done(&htc->ctl_resp)) {
511 				/*
512 				 * this is a fatal error, target should not be
513 				 * sending unsolicited messages on the ep 0
514 				 */
515 				ath10k_warn("HTC rx ctrl still processing\n");
516 				status = -EINVAL;
517 				complete(&htc->ctl_resp);
518 				goto out;
519 			}
520 
521 			htc->control_resp_len =
522 				min_t(int, skb->len,
523 				      ATH10K_HTC_MAX_CTRL_MSG_LEN);
524 
525 			memcpy(htc->control_resp_buffer, skb->data,
526 			       htc->control_resp_len);
527 
528 			complete(&htc->ctl_resp);
529 			break;
530 		case ATH10K_HTC_MSG_SEND_SUSPEND_COMPLETE:
531 			htc->htc_ops.target_send_suspend_complete(ar);
532 		}
533 		goto out;
534 	}
535 
536 	ath10k_dbg(ATH10K_DBG_HTC, "htc rx completion ep %d skb %p\n",
537 		   eid, skb);
538 	ep->ep_ops.ep_rx_complete(ar, skb);
539 
540 	/* skb is now owned by the rx completion handler */
541 	skb = NULL;
542 out:
543 	kfree_skb(skb);
544 
545 	return status;
546 }
547 
548 static void ath10k_htc_control_rx_complete(struct ath10k *ar,
549 					   struct sk_buff *skb)
550 {
551 	/* This is unexpected. FW is not supposed to send regular rx on this
552 	 * endpoint. */
553 	ath10k_warn("unexpected htc rx\n");
554 	kfree_skb(skb);
555 }
556 
557 /***************/
558 /* Init/Deinit */
559 /***************/
560 
561 static const char *htc_service_name(enum ath10k_htc_svc_id id)
562 {
563 	switch (id) {
564 	case ATH10K_HTC_SVC_ID_RESERVED:
565 		return "Reserved";
566 	case ATH10K_HTC_SVC_ID_RSVD_CTRL:
567 		return "Control";
568 	case ATH10K_HTC_SVC_ID_WMI_CONTROL:
569 		return "WMI";
570 	case ATH10K_HTC_SVC_ID_WMI_DATA_BE:
571 		return "DATA BE";
572 	case ATH10K_HTC_SVC_ID_WMI_DATA_BK:
573 		return "DATA BK";
574 	case ATH10K_HTC_SVC_ID_WMI_DATA_VI:
575 		return "DATA VI";
576 	case ATH10K_HTC_SVC_ID_WMI_DATA_VO:
577 		return "DATA VO";
578 	case ATH10K_HTC_SVC_ID_NMI_CONTROL:
579 		return "NMI Control";
580 	case ATH10K_HTC_SVC_ID_NMI_DATA:
581 		return "NMI Data";
582 	case ATH10K_HTC_SVC_ID_HTT_DATA_MSG:
583 		return "HTT Data";
584 	case ATH10K_HTC_SVC_ID_TEST_RAW_STREAMS:
585 		return "RAW";
586 	}
587 
588 	return "Unknown";
589 }
590 
591 static void ath10k_htc_reset_endpoint_states(struct ath10k_htc *htc)
592 {
593 	struct ath10k_htc_ep *ep;
594 	int i;
595 
596 	for (i = ATH10K_HTC_EP_0; i < ATH10K_HTC_EP_COUNT; i++) {
597 		ep = &htc->endpoint[i];
598 		ep->service_id = ATH10K_HTC_SVC_ID_UNUSED;
599 		ep->max_ep_message_len = 0;
600 		ep->max_tx_queue_depth = 0;
601 		ep->eid = i;
602 		skb_queue_head_init(&ep->tx_queue);
603 		ep->htc = htc;
604 		ep->tx_credit_flow_enabled = true;
605 		INIT_WORK(&ep->send_work, ath10k_htc_send_work);
606 	}
607 }
608 
609 static void ath10k_htc_setup_target_buffer_assignments(struct ath10k_htc *htc)
610 {
611 	struct ath10k_htc_svc_tx_credits *entry;
612 
613 	entry = &htc->service_tx_alloc[0];
614 
615 	/*
616 	 * for PCIE allocate all credists/HTC buffers to WMI.
617 	 * no buffers are used/required for data. data always
618 	 * remains on host.
619 	 */
620 	entry++;
621 	entry->service_id = ATH10K_HTC_SVC_ID_WMI_CONTROL;
622 	entry->credit_allocation = htc->total_transmit_credits;
623 }
624 
625 static u8 ath10k_htc_get_credit_allocation(struct ath10k_htc *htc,
626 					   u16 service_id)
627 {
628 	u8 allocation = 0;
629 	int i;
630 
631 	for (i = 0; i < ATH10K_HTC_EP_COUNT; i++) {
632 		if (htc->service_tx_alloc[i].service_id == service_id)
633 			allocation =
634 			    htc->service_tx_alloc[i].credit_allocation;
635 	}
636 
637 	return allocation;
638 }
639 
640 int ath10k_htc_wait_target(struct ath10k_htc *htc)
641 {
642 	int status = 0;
643 	struct ath10k_htc_svc_conn_req conn_req;
644 	struct ath10k_htc_svc_conn_resp conn_resp;
645 	struct ath10k_htc_msg *msg;
646 	u16 message_id;
647 	u16 credit_count;
648 	u16 credit_size;
649 
650 	INIT_COMPLETION(htc->ctl_resp);
651 
652 	status = ath10k_hif_start(htc->ar);
653 	if (status) {
654 		ath10k_err("could not start HIF (%d)\n", status);
655 		goto err_start;
656 	}
657 
658 	status = wait_for_completion_timeout(&htc->ctl_resp,
659 					     ATH10K_HTC_WAIT_TIMEOUT_HZ);
660 	if (status <= 0) {
661 		if (status == 0)
662 			status = -ETIMEDOUT;
663 
664 		ath10k_err("ctl_resp never came in (%d)\n", status);
665 		goto err_target;
666 	}
667 
668 	if (htc->control_resp_len < sizeof(msg->hdr) + sizeof(msg->ready)) {
669 		ath10k_err("Invalid HTC ready msg len:%d\n",
670 			   htc->control_resp_len);
671 
672 		status = -ECOMM;
673 		goto err_target;
674 	}
675 
676 	msg = (struct ath10k_htc_msg *)htc->control_resp_buffer;
677 	message_id   = __le16_to_cpu(msg->hdr.message_id);
678 	credit_count = __le16_to_cpu(msg->ready.credit_count);
679 	credit_size  = __le16_to_cpu(msg->ready.credit_size);
680 
681 	if (message_id != ATH10K_HTC_MSG_READY_ID) {
682 		ath10k_err("Invalid HTC ready msg: 0x%x\n", message_id);
683 		status = -ECOMM;
684 		goto err_target;
685 	}
686 
687 	htc->total_transmit_credits = credit_count;
688 	htc->target_credit_size = credit_size;
689 
690 	ath10k_dbg(ATH10K_DBG_HTC,
691 		   "Target ready! transmit resources: %d size:%d\n",
692 		   htc->total_transmit_credits,
693 		   htc->target_credit_size);
694 
695 	if ((htc->total_transmit_credits == 0) ||
696 	    (htc->target_credit_size == 0)) {
697 		status = -ECOMM;
698 		ath10k_err("Invalid credit size received\n");
699 		goto err_target;
700 	}
701 
702 	ath10k_htc_setup_target_buffer_assignments(htc);
703 
704 	/* setup our pseudo HTC control endpoint connection */
705 	memset(&conn_req, 0, sizeof(conn_req));
706 	memset(&conn_resp, 0, sizeof(conn_resp));
707 	conn_req.ep_ops.ep_tx_complete = ath10k_htc_control_tx_complete;
708 	conn_req.ep_ops.ep_rx_complete = ath10k_htc_control_rx_complete;
709 	conn_req.max_send_queue_depth = ATH10K_NUM_CONTROL_TX_BUFFERS;
710 	conn_req.service_id = ATH10K_HTC_SVC_ID_RSVD_CTRL;
711 
712 	/* connect fake service */
713 	status = ath10k_htc_connect_service(htc, &conn_req, &conn_resp);
714 	if (status) {
715 		ath10k_err("could not connect to htc service (%d)\n", status);
716 		goto err_target;
717 	}
718 
719 	return 0;
720 err_target:
721 	ath10k_hif_stop(htc->ar);
722 err_start:
723 	return status;
724 }
725 
726 int ath10k_htc_connect_service(struct ath10k_htc *htc,
727 			       struct ath10k_htc_svc_conn_req *conn_req,
728 			       struct ath10k_htc_svc_conn_resp *conn_resp)
729 {
730 	struct ath10k_htc_msg *msg;
731 	struct ath10k_htc_conn_svc *req_msg;
732 	struct ath10k_htc_conn_svc_response resp_msg_dummy;
733 	struct ath10k_htc_conn_svc_response *resp_msg = &resp_msg_dummy;
734 	enum ath10k_htc_ep_id assigned_eid = ATH10K_HTC_EP_COUNT;
735 	struct ath10k_htc_ep *ep;
736 	struct sk_buff *skb;
737 	unsigned int max_msg_size = 0;
738 	int length, status;
739 	bool disable_credit_flow_ctrl = false;
740 	u16 message_id, service_id, flags = 0;
741 	u8 tx_alloc = 0;
742 
743 	/* special case for HTC pseudo control service */
744 	if (conn_req->service_id == ATH10K_HTC_SVC_ID_RSVD_CTRL) {
745 		disable_credit_flow_ctrl = true;
746 		assigned_eid = ATH10K_HTC_EP_0;
747 		max_msg_size = ATH10K_HTC_MAX_CTRL_MSG_LEN;
748 		memset(&resp_msg_dummy, 0, sizeof(resp_msg_dummy));
749 		goto setup;
750 	}
751 
752 	tx_alloc = ath10k_htc_get_credit_allocation(htc,
753 						    conn_req->service_id);
754 	if (!tx_alloc)
755 		ath10k_dbg(ATH10K_DBG_HTC,
756 			   "HTC Service %s does not allocate target credits\n",
757 			   htc_service_name(conn_req->service_id));
758 
759 	skb = ath10k_htc_build_tx_ctrl_skb(htc->ar);
760 	if (!skb) {
761 		ath10k_err("Failed to allocate HTC packet\n");
762 		return -ENOMEM;
763 	}
764 
765 	length = sizeof(msg->hdr) + sizeof(msg->connect_service);
766 	skb_put(skb, length);
767 	memset(skb->data, 0, length);
768 
769 	msg = (struct ath10k_htc_msg *)skb->data;
770 	msg->hdr.message_id =
771 		__cpu_to_le16(ATH10K_HTC_MSG_CONNECT_SERVICE_ID);
772 
773 	flags |= SM(tx_alloc, ATH10K_HTC_CONN_FLAGS_RECV_ALLOC);
774 
775 	req_msg = &msg->connect_service;
776 	req_msg->flags = __cpu_to_le16(flags);
777 	req_msg->service_id = __cpu_to_le16(conn_req->service_id);
778 
779 	/* Only enable credit flow control for WMI ctrl service */
780 	if (conn_req->service_id != ATH10K_HTC_SVC_ID_WMI_CONTROL) {
781 		flags |= ATH10K_HTC_CONN_FLAGS_DISABLE_CREDIT_FLOW_CTRL;
782 		disable_credit_flow_ctrl = true;
783 	}
784 
785 	INIT_COMPLETION(htc->ctl_resp);
786 
787 	status = ath10k_htc_send(htc, ATH10K_HTC_EP_0, skb);
788 	if (status) {
789 		kfree_skb(skb);
790 		return status;
791 	}
792 
793 	/* wait for response */
794 	status = wait_for_completion_timeout(&htc->ctl_resp,
795 					     ATH10K_HTC_CONN_SVC_TIMEOUT_HZ);
796 	if (status <= 0) {
797 		if (status == 0)
798 			status = -ETIMEDOUT;
799 		ath10k_err("Service connect timeout: %d\n", status);
800 		return status;
801 	}
802 
803 	/* we controlled the buffer creation, it's aligned */
804 	msg = (struct ath10k_htc_msg *)htc->control_resp_buffer;
805 	resp_msg = &msg->connect_service_response;
806 	message_id = __le16_to_cpu(msg->hdr.message_id);
807 	service_id = __le16_to_cpu(resp_msg->service_id);
808 
809 	if ((message_id != ATH10K_HTC_MSG_CONNECT_SERVICE_RESP_ID) ||
810 	    (htc->control_resp_len < sizeof(msg->hdr) +
811 	     sizeof(msg->connect_service_response))) {
812 		ath10k_err("Invalid resp message ID 0x%x", message_id);
813 		return -EPROTO;
814 	}
815 
816 	ath10k_dbg(ATH10K_DBG_HTC,
817 		   "HTC Service %s connect response: status: 0x%x, assigned ep: 0x%x\n",
818 		   htc_service_name(service_id),
819 		   resp_msg->status, resp_msg->eid);
820 
821 	conn_resp->connect_resp_code = resp_msg->status;
822 
823 	/* check response status */
824 	if (resp_msg->status != ATH10K_HTC_CONN_SVC_STATUS_SUCCESS) {
825 		ath10k_err("HTC Service %s connect request failed: 0x%x)\n",
826 			   htc_service_name(service_id),
827 			   resp_msg->status);
828 		return -EPROTO;
829 	}
830 
831 	assigned_eid = (enum ath10k_htc_ep_id)resp_msg->eid;
832 	max_msg_size = __le16_to_cpu(resp_msg->max_msg_size);
833 
834 setup:
835 
836 	if (assigned_eid >= ATH10K_HTC_EP_COUNT)
837 		return -EPROTO;
838 
839 	if (max_msg_size == 0)
840 		return -EPROTO;
841 
842 	ep = &htc->endpoint[assigned_eid];
843 	ep->eid = assigned_eid;
844 
845 	if (ep->service_id != ATH10K_HTC_SVC_ID_UNUSED)
846 		return -EPROTO;
847 
848 	/* return assigned endpoint to caller */
849 	conn_resp->eid = assigned_eid;
850 	conn_resp->max_msg_len = __le16_to_cpu(resp_msg->max_msg_size);
851 
852 	/* setup the endpoint */
853 	ep->service_id = conn_req->service_id;
854 	ep->max_tx_queue_depth = conn_req->max_send_queue_depth;
855 	ep->max_ep_message_len = __le16_to_cpu(resp_msg->max_msg_size);
856 	ep->tx_credits = tx_alloc;
857 	ep->tx_credit_size = htc->target_credit_size;
858 	ep->tx_credits_per_max_message = ep->max_ep_message_len /
859 					 htc->target_credit_size;
860 
861 	if (ep->max_ep_message_len % htc->target_credit_size)
862 		ep->tx_credits_per_max_message++;
863 
864 	/* copy all the callbacks */
865 	ep->ep_ops = conn_req->ep_ops;
866 
867 	status = ath10k_hif_map_service_to_pipe(htc->ar,
868 						ep->service_id,
869 						&ep->ul_pipe_id,
870 						&ep->dl_pipe_id,
871 						&ep->ul_is_polled,
872 						&ep->dl_is_polled);
873 	if (status)
874 		return status;
875 
876 	ath10k_dbg(ATH10K_DBG_HTC,
877 		   "HTC service: %s UL pipe: %d DL pipe: %d eid: %d ready\n",
878 		   htc_service_name(ep->service_id), ep->ul_pipe_id,
879 		   ep->dl_pipe_id, ep->eid);
880 
881 	ath10k_dbg(ATH10K_DBG_HTC,
882 		   "EP %d UL polled: %d, DL polled: %d\n",
883 		   ep->eid, ep->ul_is_polled, ep->dl_is_polled);
884 
885 	if (disable_credit_flow_ctrl && ep->tx_credit_flow_enabled) {
886 		ep->tx_credit_flow_enabled = false;
887 		ath10k_dbg(ATH10K_DBG_HTC,
888 			   "HTC service: %s eid: %d TX flow control disabled\n",
889 			   htc_service_name(ep->service_id), assigned_eid);
890 	}
891 
892 	return status;
893 }
894 
895 struct sk_buff *ath10k_htc_alloc_skb(int size)
896 {
897 	struct sk_buff *skb;
898 
899 	skb = dev_alloc_skb(size + sizeof(struct ath10k_htc_hdr));
900 	if (!skb) {
901 		ath10k_warn("could not allocate HTC tx skb\n");
902 		return NULL;
903 	}
904 
905 	skb_reserve(skb, sizeof(struct ath10k_htc_hdr));
906 
907 	/* FW/HTC requires 4-byte aligned streams */
908 	if (!IS_ALIGNED((unsigned long)skb->data, 4))
909 		ath10k_warn("Unaligned HTC tx skb\n");
910 
911 	return skb;
912 }
913 
914 int ath10k_htc_start(struct ath10k_htc *htc)
915 {
916 	struct sk_buff *skb;
917 	int status = 0;
918 	struct ath10k_htc_msg *msg;
919 
920 	skb = ath10k_htc_build_tx_ctrl_skb(htc->ar);
921 	if (!skb)
922 		return -ENOMEM;
923 
924 	skb_put(skb, sizeof(msg->hdr) + sizeof(msg->setup_complete_ext));
925 	memset(skb->data, 0, skb->len);
926 
927 	msg = (struct ath10k_htc_msg *)skb->data;
928 	msg->hdr.message_id =
929 		__cpu_to_le16(ATH10K_HTC_MSG_SETUP_COMPLETE_EX_ID);
930 
931 	ath10k_dbg(ATH10K_DBG_HTC, "HTC is using TX credit flow control\n");
932 
933 	status = ath10k_htc_send(htc, ATH10K_HTC_EP_0, skb);
934 	if (status) {
935 		kfree_skb(skb);
936 		return status;
937 	}
938 
939 	return 0;
940 }
941 
942 /*
943  * stop HTC communications, i.e. stop interrupt reception, and flush all
944  * queued buffers
945  */
946 void ath10k_htc_stop(struct ath10k_htc *htc)
947 {
948 	int i;
949 	struct ath10k_htc_ep *ep;
950 
951 	spin_lock_bh(&htc->tx_lock);
952 	htc->stopped = true;
953 	spin_unlock_bh(&htc->tx_lock);
954 
955 	for (i = ATH10K_HTC_EP_0; i < ATH10K_HTC_EP_COUNT; i++) {
956 		ep = &htc->endpoint[i];
957 		ath10k_htc_flush_endpoint_tx(htc, ep);
958 	}
959 
960 	ath10k_hif_stop(htc->ar);
961 }
962 
963 /* registered target arrival callback from the HIF layer */
964 int ath10k_htc_init(struct ath10k *ar)
965 {
966 	struct ath10k_hif_cb htc_callbacks;
967 	struct ath10k_htc_ep *ep = NULL;
968 	struct ath10k_htc *htc = &ar->htc;
969 
970 	spin_lock_init(&htc->tx_lock);
971 
972 	htc->stopped = false;
973 	ath10k_htc_reset_endpoint_states(htc);
974 
975 	/* setup HIF layer callbacks */
976 	htc_callbacks.rx_completion = ath10k_htc_rx_completion_handler;
977 	htc_callbacks.tx_completion = ath10k_htc_tx_completion_handler;
978 	htc->ar = ar;
979 
980 	/* Get HIF default pipe for HTC message exchange */
981 	ep = &htc->endpoint[ATH10K_HTC_EP_0];
982 
983 	ath10k_hif_set_callbacks(ar, &htc_callbacks);
984 	ath10k_hif_get_default_pipe(ar, &ep->ul_pipe_id, &ep->dl_pipe_id);
985 
986 	init_completion(&htc->ctl_resp);
987 
988 	return 0;
989 }
990