xref: /linux/drivers/net/wireless/ath/ath10k/htc.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
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 		return NULL;
50 
51 	skb_reserve(skb, 20); /* FIXME: why 20 bytes? */
52 	WARN_ONCE((unsigned long)skb->data & 3, "unaligned skb");
53 
54 	skb_cb = ATH10K_SKB_CB(skb);
55 	memset(skb_cb, 0, sizeof(*skb_cb));
56 
57 	ath10k_dbg(ar, ATH10K_DBG_HTC, "%s: skb %p\n", __func__, skb);
58 	return skb;
59 }
60 
61 static inline void ath10k_htc_restore_tx_skb(struct ath10k_htc *htc,
62 					     struct sk_buff *skb)
63 {
64 	struct ath10k_skb_cb *skb_cb = ATH10K_SKB_CB(skb);
65 
66 	dma_unmap_single(htc->ar->dev, skb_cb->paddr, skb->len, DMA_TO_DEVICE);
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 	struct ath10k *ar = ep->htc->ar;
74 
75 	ath10k_dbg(ar, ATH10K_DBG_HTC, "%s: ep %d skb %p\n", __func__,
76 		   ep->eid, skb);
77 
78 	ath10k_htc_restore_tx_skb(ep->htc, skb);
79 
80 	if (!ep->ep_ops.ep_tx_complete) {
81 		ath10k_warn(ar, "no tx handler for eid %d\n", ep->eid);
82 		dev_kfree_skb_any(skb);
83 		return;
84 	}
85 
86 	ep->ep_ops.ep_tx_complete(ep->htc->ar, skb);
87 }
88 
89 static void ath10k_htc_prepare_tx_skb(struct ath10k_htc_ep *ep,
90 				      struct sk_buff *skb)
91 {
92 	struct ath10k_htc_hdr *hdr;
93 
94 	hdr = (struct ath10k_htc_hdr *)skb->data;
95 
96 	hdr->eid = ep->eid;
97 	hdr->len = __cpu_to_le16(skb->len - sizeof(*hdr));
98 	hdr->flags = 0;
99 	hdr->flags |= ATH10K_HTC_FLAG_NEED_CREDIT_UPDATE;
100 
101 	spin_lock_bh(&ep->htc->tx_lock);
102 	hdr->seq_no = ep->seq_no++;
103 	spin_unlock_bh(&ep->htc->tx_lock);
104 }
105 
106 int ath10k_htc_send(struct ath10k_htc *htc,
107 		    enum ath10k_htc_ep_id eid,
108 		    struct sk_buff *skb)
109 {
110 	struct ath10k *ar = htc->ar;
111 	struct ath10k_htc_ep *ep = &htc->endpoint[eid];
112 	struct ath10k_skb_cb *skb_cb = ATH10K_SKB_CB(skb);
113 	struct ath10k_hif_sg_item sg_item;
114 	struct device *dev = htc->ar->dev;
115 	int credits = 0;
116 	int ret;
117 
118 	if (htc->ar->state == ATH10K_STATE_WEDGED)
119 		return -ECOMM;
120 
121 	if (eid >= ATH10K_HTC_EP_COUNT) {
122 		ath10k_warn(ar, "Invalid endpoint id: %d\n", eid);
123 		return -ENOENT;
124 	}
125 
126 	skb_push(skb, sizeof(struct ath10k_htc_hdr));
127 
128 	if (ep->tx_credit_flow_enabled) {
129 		credits = DIV_ROUND_UP(skb->len, htc->target_credit_size);
130 		spin_lock_bh(&htc->tx_lock);
131 		if (ep->tx_credits < credits) {
132 			spin_unlock_bh(&htc->tx_lock);
133 			ret = -EAGAIN;
134 			goto err_pull;
135 		}
136 		ep->tx_credits -= credits;
137 		ath10k_dbg(ar, ATH10K_DBG_HTC,
138 			   "htc ep %d consumed %d credits (total %d)\n",
139 			   eid, credits, ep->tx_credits);
140 		spin_unlock_bh(&htc->tx_lock);
141 	}
142 
143 	ath10k_htc_prepare_tx_skb(ep, skb);
144 
145 	skb_cb->eid = eid;
146 	skb_cb->paddr = dma_map_single(dev, skb->data, skb->len, DMA_TO_DEVICE);
147 	ret = dma_mapping_error(dev, skb_cb->paddr);
148 	if (ret) {
149 		ret = -EIO;
150 		goto err_credits;
151 	}
152 
153 	sg_item.transfer_id = ep->eid;
154 	sg_item.transfer_context = skb;
155 	sg_item.vaddr = skb->data;
156 	sg_item.paddr = skb_cb->paddr;
157 	sg_item.len = skb->len;
158 
159 	ret = ath10k_hif_tx_sg(htc->ar, ep->ul_pipe_id, &sg_item, 1);
160 	if (ret)
161 		goto err_unmap;
162 
163 	return 0;
164 
165 err_unmap:
166 	dma_unmap_single(dev, skb_cb->paddr, skb->len, DMA_TO_DEVICE);
167 err_credits:
168 	if (ep->tx_credit_flow_enabled) {
169 		spin_lock_bh(&htc->tx_lock);
170 		ep->tx_credits += credits;
171 		ath10k_dbg(ar, ATH10K_DBG_HTC,
172 			   "htc ep %d reverted %d credits back (total %d)\n",
173 			   eid, credits, ep->tx_credits);
174 		spin_unlock_bh(&htc->tx_lock);
175 
176 		if (ep->ep_ops.ep_tx_credits)
177 			ep->ep_ops.ep_tx_credits(htc->ar);
178 	}
179 err_pull:
180 	skb_pull(skb, sizeof(struct ath10k_htc_hdr));
181 	return ret;
182 }
183 
184 static int ath10k_htc_tx_completion_handler(struct ath10k *ar,
185 					    struct sk_buff *skb)
186 {
187 	struct ath10k_htc *htc = &ar->htc;
188 	struct ath10k_skb_cb *skb_cb;
189 	struct ath10k_htc_ep *ep;
190 
191 	if (WARN_ON_ONCE(!skb))
192 		return 0;
193 
194 	skb_cb = ATH10K_SKB_CB(skb);
195 	ep = &htc->endpoint[skb_cb->eid];
196 
197 	ath10k_htc_notify_tx_completion(ep, skb);
198 	/* the skb now belongs to the completion handler */
199 
200 	return 0;
201 }
202 
203 /***********/
204 /* Receive */
205 /***********/
206 
207 static void
208 ath10k_htc_process_credit_report(struct ath10k_htc *htc,
209 				 const struct ath10k_htc_credit_report *report,
210 				 int len,
211 				 enum ath10k_htc_ep_id eid)
212 {
213 	struct ath10k *ar = htc->ar;
214 	struct ath10k_htc_ep *ep;
215 	int i, n_reports;
216 
217 	if (len % sizeof(*report))
218 		ath10k_warn(ar, "Uneven credit report len %d", len);
219 
220 	n_reports = len / sizeof(*report);
221 
222 	spin_lock_bh(&htc->tx_lock);
223 	for (i = 0; i < n_reports; i++, report++) {
224 		if (report->eid >= ATH10K_HTC_EP_COUNT)
225 			break;
226 
227 		ep = &htc->endpoint[report->eid];
228 		ep->tx_credits += report->credits;
229 
230 		ath10k_dbg(ar, ATH10K_DBG_HTC, "htc ep %d got %d credits (total %d)\n",
231 			   report->eid, report->credits, ep->tx_credits);
232 
233 		if (ep->ep_ops.ep_tx_credits) {
234 			spin_unlock_bh(&htc->tx_lock);
235 			ep->ep_ops.ep_tx_credits(htc->ar);
236 			spin_lock_bh(&htc->tx_lock);
237 		}
238 	}
239 	spin_unlock_bh(&htc->tx_lock);
240 }
241 
242 static int ath10k_htc_process_trailer(struct ath10k_htc *htc,
243 				      u8 *buffer,
244 				      int length,
245 				      enum ath10k_htc_ep_id src_eid)
246 {
247 	struct ath10k *ar = htc->ar;
248 	int status = 0;
249 	struct ath10k_htc_record *record;
250 	u8 *orig_buffer;
251 	int orig_length;
252 	size_t len;
253 
254 	orig_buffer = buffer;
255 	orig_length = length;
256 
257 	while (length > 0) {
258 		record = (struct ath10k_htc_record *)buffer;
259 
260 		if (length < sizeof(record->hdr)) {
261 			status = -EINVAL;
262 			break;
263 		}
264 
265 		if (record->hdr.len > length) {
266 			/* no room left in buffer for record */
267 			ath10k_warn(ar, "Invalid record length: %d\n",
268 				    record->hdr.len);
269 			status = -EINVAL;
270 			break;
271 		}
272 
273 		switch (record->hdr.id) {
274 		case ATH10K_HTC_RECORD_CREDITS:
275 			len = sizeof(struct ath10k_htc_credit_report);
276 			if (record->hdr.len < len) {
277 				ath10k_warn(ar, "Credit report too long\n");
278 				status = -EINVAL;
279 				break;
280 			}
281 			ath10k_htc_process_credit_report(htc,
282 							 record->credit_report,
283 							 record->hdr.len,
284 							 src_eid);
285 			break;
286 		default:
287 			ath10k_warn(ar, "Unhandled record: id:%d length:%d\n",
288 				    record->hdr.id, record->hdr.len);
289 			break;
290 		}
291 
292 		if (status)
293 			break;
294 
295 		/* multiple records may be present in a trailer */
296 		buffer += sizeof(record->hdr) + record->hdr.len;
297 		length -= sizeof(record->hdr) + record->hdr.len;
298 	}
299 
300 	if (status)
301 		ath10k_dbg_dump(ar, ATH10K_DBG_HTC, "htc rx bad trailer", "",
302 				orig_buffer, orig_length);
303 
304 	return status;
305 }
306 
307 static int ath10k_htc_rx_completion_handler(struct ath10k *ar,
308 					    struct sk_buff *skb)
309 {
310 	int status = 0;
311 	struct ath10k_htc *htc = &ar->htc;
312 	struct ath10k_htc_hdr *hdr;
313 	struct ath10k_htc_ep *ep;
314 	u16 payload_len;
315 	u32 trailer_len = 0;
316 	size_t min_len;
317 	u8 eid;
318 	bool trailer_present;
319 
320 	hdr = (struct ath10k_htc_hdr *)skb->data;
321 	skb_pull(skb, sizeof(*hdr));
322 
323 	eid = hdr->eid;
324 
325 	if (eid >= ATH10K_HTC_EP_COUNT) {
326 		ath10k_warn(ar, "HTC Rx: invalid eid %d\n", eid);
327 		ath10k_dbg_dump(ar, ATH10K_DBG_HTC, "htc bad header", "",
328 				hdr, sizeof(*hdr));
329 		status = -EINVAL;
330 		goto out;
331 	}
332 
333 	ep = &htc->endpoint[eid];
334 
335 	/*
336 	 * If this endpoint that received a message from the target has
337 	 * a to-target HIF pipe whose send completions are polled rather
338 	 * than interrupt-driven, this is a good point to ask HIF to check
339 	 * whether it has any completed sends to handle.
340 	 */
341 	if (ep->ul_is_polled)
342 		ath10k_htc_send_complete_check(ep, 1);
343 
344 	payload_len = __le16_to_cpu(hdr->len);
345 
346 	if (payload_len + sizeof(*hdr) > ATH10K_HTC_MAX_LEN) {
347 		ath10k_warn(ar, "HTC rx frame too long, len: %zu\n",
348 			    payload_len + sizeof(*hdr));
349 		ath10k_dbg_dump(ar, ATH10K_DBG_HTC, "htc bad rx pkt len", "",
350 				hdr, sizeof(*hdr));
351 		status = -EINVAL;
352 		goto out;
353 	}
354 
355 	if (skb->len < payload_len) {
356 		ath10k_dbg(ar, ATH10K_DBG_HTC,
357 			   "HTC Rx: insufficient length, got %d, expected %d\n",
358 			   skb->len, payload_len);
359 		ath10k_dbg_dump(ar, ATH10K_DBG_HTC, "htc bad rx pkt len",
360 				"", hdr, sizeof(*hdr));
361 		status = -EINVAL;
362 		goto out;
363 	}
364 
365 	/* get flags to check for trailer */
366 	trailer_present = hdr->flags & ATH10K_HTC_FLAG_TRAILER_PRESENT;
367 	if (trailer_present) {
368 		u8 *trailer;
369 
370 		trailer_len = hdr->trailer_len;
371 		min_len = sizeof(struct ath10k_ath10k_htc_record_hdr);
372 
373 		if ((trailer_len < min_len) ||
374 		    (trailer_len > payload_len)) {
375 			ath10k_warn(ar, "Invalid trailer length: %d\n",
376 				    trailer_len);
377 			status = -EPROTO;
378 			goto out;
379 		}
380 
381 		trailer = (u8 *)hdr;
382 		trailer += sizeof(*hdr);
383 		trailer += payload_len;
384 		trailer -= trailer_len;
385 		status = ath10k_htc_process_trailer(htc, trailer,
386 						    trailer_len, hdr->eid);
387 		if (status)
388 			goto out;
389 
390 		skb_trim(skb, skb->len - trailer_len);
391 	}
392 
393 	if (((int)payload_len - (int)trailer_len) <= 0)
394 		/* zero length packet with trailer data, just drop these */
395 		goto out;
396 
397 	if (eid == ATH10K_HTC_EP_0) {
398 		struct ath10k_htc_msg *msg = (struct ath10k_htc_msg *)skb->data;
399 
400 		switch (__le16_to_cpu(msg->hdr.message_id)) {
401 		case ATH10K_HTC_MSG_READY_ID:
402 		case ATH10K_HTC_MSG_CONNECT_SERVICE_RESP_ID:
403 			/* handle HTC control message */
404 			if (completion_done(&htc->ctl_resp)) {
405 				/*
406 				 * this is a fatal error, target should not be
407 				 * sending unsolicited messages on the ep 0
408 				 */
409 				ath10k_warn(ar, "HTC rx ctrl still processing\n");
410 				status = -EINVAL;
411 				complete(&htc->ctl_resp);
412 				goto out;
413 			}
414 
415 			htc->control_resp_len =
416 				min_t(int, skb->len,
417 				      ATH10K_HTC_MAX_CTRL_MSG_LEN);
418 
419 			memcpy(htc->control_resp_buffer, skb->data,
420 			       htc->control_resp_len);
421 
422 			complete(&htc->ctl_resp);
423 			break;
424 		case ATH10K_HTC_MSG_SEND_SUSPEND_COMPLETE:
425 			htc->htc_ops.target_send_suspend_complete(ar);
426 			break;
427 		default:
428 			ath10k_warn(ar, "ignoring unsolicited htc ep0 event\n");
429 			break;
430 		}
431 		goto out;
432 	}
433 
434 	ath10k_dbg(ar, ATH10K_DBG_HTC, "htc rx completion ep %d skb %p\n",
435 		   eid, skb);
436 	ep->ep_ops.ep_rx_complete(ar, skb);
437 
438 	/* skb is now owned by the rx completion handler */
439 	skb = NULL;
440 out:
441 	kfree_skb(skb);
442 
443 	return status;
444 }
445 
446 static void ath10k_htc_control_rx_complete(struct ath10k *ar,
447 					   struct sk_buff *skb)
448 {
449 	/* This is unexpected. FW is not supposed to send regular rx on this
450 	 * endpoint. */
451 	ath10k_warn(ar, "unexpected htc rx\n");
452 	kfree_skb(skb);
453 }
454 
455 /***************/
456 /* Init/Deinit */
457 /***************/
458 
459 static const char *htc_service_name(enum ath10k_htc_svc_id id)
460 {
461 	switch (id) {
462 	case ATH10K_HTC_SVC_ID_RESERVED:
463 		return "Reserved";
464 	case ATH10K_HTC_SVC_ID_RSVD_CTRL:
465 		return "Control";
466 	case ATH10K_HTC_SVC_ID_WMI_CONTROL:
467 		return "WMI";
468 	case ATH10K_HTC_SVC_ID_WMI_DATA_BE:
469 		return "DATA BE";
470 	case ATH10K_HTC_SVC_ID_WMI_DATA_BK:
471 		return "DATA BK";
472 	case ATH10K_HTC_SVC_ID_WMI_DATA_VI:
473 		return "DATA VI";
474 	case ATH10K_HTC_SVC_ID_WMI_DATA_VO:
475 		return "DATA VO";
476 	case ATH10K_HTC_SVC_ID_NMI_CONTROL:
477 		return "NMI Control";
478 	case ATH10K_HTC_SVC_ID_NMI_DATA:
479 		return "NMI Data";
480 	case ATH10K_HTC_SVC_ID_HTT_DATA_MSG:
481 		return "HTT Data";
482 	case ATH10K_HTC_SVC_ID_TEST_RAW_STREAMS:
483 		return "RAW";
484 	}
485 
486 	return "Unknown";
487 }
488 
489 static void ath10k_htc_reset_endpoint_states(struct ath10k_htc *htc)
490 {
491 	struct ath10k_htc_ep *ep;
492 	int i;
493 
494 	for (i = ATH10K_HTC_EP_0; i < ATH10K_HTC_EP_COUNT; i++) {
495 		ep = &htc->endpoint[i];
496 		ep->service_id = ATH10K_HTC_SVC_ID_UNUSED;
497 		ep->max_ep_message_len = 0;
498 		ep->max_tx_queue_depth = 0;
499 		ep->eid = i;
500 		ep->htc = htc;
501 		ep->tx_credit_flow_enabled = true;
502 	}
503 }
504 
505 static void ath10k_htc_setup_target_buffer_assignments(struct ath10k_htc *htc)
506 {
507 	struct ath10k_htc_svc_tx_credits *entry;
508 
509 	entry = &htc->service_tx_alloc[0];
510 
511 	/*
512 	 * for PCIE allocate all credists/HTC buffers to WMI.
513 	 * no buffers are used/required for data. data always
514 	 * remains on host.
515 	 */
516 	entry++;
517 	entry->service_id = ATH10K_HTC_SVC_ID_WMI_CONTROL;
518 	entry->credit_allocation = htc->total_transmit_credits;
519 }
520 
521 static u8 ath10k_htc_get_credit_allocation(struct ath10k_htc *htc,
522 					   u16 service_id)
523 {
524 	u8 allocation = 0;
525 	int i;
526 
527 	for (i = 0; i < ATH10K_HTC_EP_COUNT; i++) {
528 		if (htc->service_tx_alloc[i].service_id == service_id)
529 			allocation =
530 			    htc->service_tx_alloc[i].credit_allocation;
531 	}
532 
533 	return allocation;
534 }
535 
536 int ath10k_htc_wait_target(struct ath10k_htc *htc)
537 {
538 	struct ath10k *ar = htc->ar;
539 	int i, status = 0;
540 	unsigned long time_left;
541 	struct ath10k_htc_svc_conn_req conn_req;
542 	struct ath10k_htc_svc_conn_resp conn_resp;
543 	struct ath10k_htc_msg *msg;
544 	u16 message_id;
545 	u16 credit_count;
546 	u16 credit_size;
547 
548 	time_left = wait_for_completion_timeout(&htc->ctl_resp,
549 						ATH10K_HTC_WAIT_TIMEOUT_HZ);
550 	if (!time_left) {
551 		/* Workaround: In some cases the PCI HIF doesn't
552 		 * receive interrupt for the control response message
553 		 * even if the buffer was completed. It is suspected
554 		 * iomap writes unmasking PCI CE irqs aren't propagated
555 		 * properly in KVM PCI-passthrough sometimes.
556 		 */
557 		ath10k_warn(ar, "failed to receive control response completion, polling..\n");
558 
559 		for (i = 0; i < CE_COUNT; i++)
560 			ath10k_hif_send_complete_check(htc->ar, i, 1);
561 
562 		time_left =
563 		wait_for_completion_timeout(&htc->ctl_resp,
564 					    ATH10K_HTC_WAIT_TIMEOUT_HZ);
565 
566 		if (!time_left)
567 			status = -ETIMEDOUT;
568 	}
569 
570 	if (status < 0) {
571 		ath10k_err(ar, "ctl_resp never came in (%d)\n", status);
572 		return status;
573 	}
574 
575 	if (htc->control_resp_len < sizeof(msg->hdr) + sizeof(msg->ready)) {
576 		ath10k_err(ar, "Invalid HTC ready msg len:%d\n",
577 			   htc->control_resp_len);
578 		return -ECOMM;
579 	}
580 
581 	msg = (struct ath10k_htc_msg *)htc->control_resp_buffer;
582 	message_id   = __le16_to_cpu(msg->hdr.message_id);
583 	credit_count = __le16_to_cpu(msg->ready.credit_count);
584 	credit_size  = __le16_to_cpu(msg->ready.credit_size);
585 
586 	if (message_id != ATH10K_HTC_MSG_READY_ID) {
587 		ath10k_err(ar, "Invalid HTC ready msg: 0x%x\n", message_id);
588 		return -ECOMM;
589 	}
590 
591 	htc->total_transmit_credits = credit_count;
592 	htc->target_credit_size = credit_size;
593 
594 	ath10k_dbg(ar, ATH10K_DBG_HTC,
595 		   "Target ready! transmit resources: %d size:%d\n",
596 		   htc->total_transmit_credits,
597 		   htc->target_credit_size);
598 
599 	if ((htc->total_transmit_credits == 0) ||
600 	    (htc->target_credit_size == 0)) {
601 		ath10k_err(ar, "Invalid credit size received\n");
602 		return -ECOMM;
603 	}
604 
605 	ath10k_htc_setup_target_buffer_assignments(htc);
606 
607 	/* setup our pseudo HTC control endpoint connection */
608 	memset(&conn_req, 0, sizeof(conn_req));
609 	memset(&conn_resp, 0, sizeof(conn_resp));
610 	conn_req.ep_ops.ep_tx_complete = ath10k_htc_control_tx_complete;
611 	conn_req.ep_ops.ep_rx_complete = ath10k_htc_control_rx_complete;
612 	conn_req.max_send_queue_depth = ATH10K_NUM_CONTROL_TX_BUFFERS;
613 	conn_req.service_id = ATH10K_HTC_SVC_ID_RSVD_CTRL;
614 
615 	/* connect fake service */
616 	status = ath10k_htc_connect_service(htc, &conn_req, &conn_resp);
617 	if (status) {
618 		ath10k_err(ar, "could not connect to htc service (%d)\n",
619 			   status);
620 		return status;
621 	}
622 
623 	return 0;
624 }
625 
626 int ath10k_htc_connect_service(struct ath10k_htc *htc,
627 			       struct ath10k_htc_svc_conn_req *conn_req,
628 			       struct ath10k_htc_svc_conn_resp *conn_resp)
629 {
630 	struct ath10k *ar = htc->ar;
631 	struct ath10k_htc_msg *msg;
632 	struct ath10k_htc_conn_svc *req_msg;
633 	struct ath10k_htc_conn_svc_response resp_msg_dummy;
634 	struct ath10k_htc_conn_svc_response *resp_msg = &resp_msg_dummy;
635 	enum ath10k_htc_ep_id assigned_eid = ATH10K_HTC_EP_COUNT;
636 	struct ath10k_htc_ep *ep;
637 	struct sk_buff *skb;
638 	unsigned int max_msg_size = 0;
639 	int length, status;
640 	unsigned long time_left;
641 	bool disable_credit_flow_ctrl = false;
642 	u16 message_id, service_id, flags = 0;
643 	u8 tx_alloc = 0;
644 
645 	/* special case for HTC pseudo control service */
646 	if (conn_req->service_id == ATH10K_HTC_SVC_ID_RSVD_CTRL) {
647 		disable_credit_flow_ctrl = true;
648 		assigned_eid = ATH10K_HTC_EP_0;
649 		max_msg_size = ATH10K_HTC_MAX_CTRL_MSG_LEN;
650 		memset(&resp_msg_dummy, 0, sizeof(resp_msg_dummy));
651 		goto setup;
652 	}
653 
654 	tx_alloc = ath10k_htc_get_credit_allocation(htc,
655 						    conn_req->service_id);
656 	if (!tx_alloc)
657 		ath10k_dbg(ar, ATH10K_DBG_BOOT,
658 			   "boot htc service %s does not allocate target credits\n",
659 			   htc_service_name(conn_req->service_id));
660 
661 	skb = ath10k_htc_build_tx_ctrl_skb(htc->ar);
662 	if (!skb) {
663 		ath10k_err(ar, "Failed to allocate HTC packet\n");
664 		return -ENOMEM;
665 	}
666 
667 	length = sizeof(msg->hdr) + sizeof(msg->connect_service);
668 	skb_put(skb, length);
669 	memset(skb->data, 0, length);
670 
671 	msg = (struct ath10k_htc_msg *)skb->data;
672 	msg->hdr.message_id =
673 		__cpu_to_le16(ATH10K_HTC_MSG_CONNECT_SERVICE_ID);
674 
675 	flags |= SM(tx_alloc, ATH10K_HTC_CONN_FLAGS_RECV_ALLOC);
676 
677 	/* Only enable credit flow control for WMI ctrl service */
678 	if (conn_req->service_id != ATH10K_HTC_SVC_ID_WMI_CONTROL) {
679 		flags |= ATH10K_HTC_CONN_FLAGS_DISABLE_CREDIT_FLOW_CTRL;
680 		disable_credit_flow_ctrl = true;
681 	}
682 
683 	req_msg = &msg->connect_service;
684 	req_msg->flags = __cpu_to_le16(flags);
685 	req_msg->service_id = __cpu_to_le16(conn_req->service_id);
686 
687 	reinit_completion(&htc->ctl_resp);
688 
689 	status = ath10k_htc_send(htc, ATH10K_HTC_EP_0, skb);
690 	if (status) {
691 		kfree_skb(skb);
692 		return status;
693 	}
694 
695 	/* wait for response */
696 	time_left = wait_for_completion_timeout(&htc->ctl_resp,
697 						ATH10K_HTC_CONN_SVC_TIMEOUT_HZ);
698 	if (!time_left) {
699 		ath10k_err(ar, "Service connect timeout\n");
700 		return -ETIMEDOUT;
701 	}
702 
703 	/* we controlled the buffer creation, it's aligned */
704 	msg = (struct ath10k_htc_msg *)htc->control_resp_buffer;
705 	resp_msg = &msg->connect_service_response;
706 	message_id = __le16_to_cpu(msg->hdr.message_id);
707 	service_id = __le16_to_cpu(resp_msg->service_id);
708 
709 	if ((message_id != ATH10K_HTC_MSG_CONNECT_SERVICE_RESP_ID) ||
710 	    (htc->control_resp_len < sizeof(msg->hdr) +
711 	     sizeof(msg->connect_service_response))) {
712 		ath10k_err(ar, "Invalid resp message ID 0x%x", message_id);
713 		return -EPROTO;
714 	}
715 
716 	ath10k_dbg(ar, ATH10K_DBG_HTC,
717 		   "HTC Service %s connect response: status: 0x%x, assigned ep: 0x%x\n",
718 		   htc_service_name(service_id),
719 		   resp_msg->status, resp_msg->eid);
720 
721 	conn_resp->connect_resp_code = resp_msg->status;
722 
723 	/* check response status */
724 	if (resp_msg->status != ATH10K_HTC_CONN_SVC_STATUS_SUCCESS) {
725 		ath10k_err(ar, "HTC Service %s connect request failed: 0x%x)\n",
726 			   htc_service_name(service_id),
727 			   resp_msg->status);
728 		return -EPROTO;
729 	}
730 
731 	assigned_eid = (enum ath10k_htc_ep_id)resp_msg->eid;
732 	max_msg_size = __le16_to_cpu(resp_msg->max_msg_size);
733 
734 setup:
735 
736 	if (assigned_eid >= ATH10K_HTC_EP_COUNT)
737 		return -EPROTO;
738 
739 	if (max_msg_size == 0)
740 		return -EPROTO;
741 
742 	ep = &htc->endpoint[assigned_eid];
743 	ep->eid = assigned_eid;
744 
745 	if (ep->service_id != ATH10K_HTC_SVC_ID_UNUSED)
746 		return -EPROTO;
747 
748 	/* return assigned endpoint to caller */
749 	conn_resp->eid = assigned_eid;
750 	conn_resp->max_msg_len = __le16_to_cpu(resp_msg->max_msg_size);
751 
752 	/* setup the endpoint */
753 	ep->service_id = conn_req->service_id;
754 	ep->max_tx_queue_depth = conn_req->max_send_queue_depth;
755 	ep->max_ep_message_len = __le16_to_cpu(resp_msg->max_msg_size);
756 	ep->tx_credits = tx_alloc;
757 	ep->tx_credit_size = htc->target_credit_size;
758 	ep->tx_credits_per_max_message = ep->max_ep_message_len /
759 					 htc->target_credit_size;
760 
761 	if (ep->max_ep_message_len % htc->target_credit_size)
762 		ep->tx_credits_per_max_message++;
763 
764 	/* copy all the callbacks */
765 	ep->ep_ops = conn_req->ep_ops;
766 
767 	status = ath10k_hif_map_service_to_pipe(htc->ar,
768 						ep->service_id,
769 						&ep->ul_pipe_id,
770 						&ep->dl_pipe_id,
771 						&ep->ul_is_polled,
772 						&ep->dl_is_polled);
773 	if (status)
774 		return status;
775 
776 	ath10k_dbg(ar, ATH10K_DBG_BOOT,
777 		   "boot htc service '%s' ul pipe %d dl pipe %d eid %d ready\n",
778 		   htc_service_name(ep->service_id), ep->ul_pipe_id,
779 		   ep->dl_pipe_id, ep->eid);
780 
781 	ath10k_dbg(ar, ATH10K_DBG_BOOT,
782 		   "boot htc ep %d ul polled %d dl polled %d\n",
783 		   ep->eid, ep->ul_is_polled, ep->dl_is_polled);
784 
785 	if (disable_credit_flow_ctrl && ep->tx_credit_flow_enabled) {
786 		ep->tx_credit_flow_enabled = false;
787 		ath10k_dbg(ar, ATH10K_DBG_BOOT,
788 			   "boot htc service '%s' eid %d TX flow control disabled\n",
789 			   htc_service_name(ep->service_id), assigned_eid);
790 	}
791 
792 	return status;
793 }
794 
795 struct sk_buff *ath10k_htc_alloc_skb(struct ath10k *ar, int size)
796 {
797 	struct sk_buff *skb;
798 
799 	skb = dev_alloc_skb(size + sizeof(struct ath10k_htc_hdr));
800 	if (!skb)
801 		return NULL;
802 
803 	skb_reserve(skb, sizeof(struct ath10k_htc_hdr));
804 
805 	/* FW/HTC requires 4-byte aligned streams */
806 	if (!IS_ALIGNED((unsigned long)skb->data, 4))
807 		ath10k_warn(ar, "Unaligned HTC tx skb\n");
808 
809 	return skb;
810 }
811 
812 int ath10k_htc_start(struct ath10k_htc *htc)
813 {
814 	struct ath10k *ar = htc->ar;
815 	struct sk_buff *skb;
816 	int status = 0;
817 	struct ath10k_htc_msg *msg;
818 
819 	skb = ath10k_htc_build_tx_ctrl_skb(htc->ar);
820 	if (!skb)
821 		return -ENOMEM;
822 
823 	skb_put(skb, sizeof(msg->hdr) + sizeof(msg->setup_complete_ext));
824 	memset(skb->data, 0, skb->len);
825 
826 	msg = (struct ath10k_htc_msg *)skb->data;
827 	msg->hdr.message_id =
828 		__cpu_to_le16(ATH10K_HTC_MSG_SETUP_COMPLETE_EX_ID);
829 
830 	ath10k_dbg(ar, ATH10K_DBG_HTC, "HTC is using TX credit flow control\n");
831 
832 	status = ath10k_htc_send(htc, ATH10K_HTC_EP_0, skb);
833 	if (status) {
834 		kfree_skb(skb);
835 		return status;
836 	}
837 
838 	return 0;
839 }
840 
841 /* registered target arrival callback from the HIF layer */
842 int ath10k_htc_init(struct ath10k *ar)
843 {
844 	struct ath10k_hif_cb htc_callbacks;
845 	struct ath10k_htc_ep *ep = NULL;
846 	struct ath10k_htc *htc = &ar->htc;
847 
848 	spin_lock_init(&htc->tx_lock);
849 
850 	ath10k_htc_reset_endpoint_states(htc);
851 
852 	/* setup HIF layer callbacks */
853 	htc_callbacks.rx_completion = ath10k_htc_rx_completion_handler;
854 	htc_callbacks.tx_completion = ath10k_htc_tx_completion_handler;
855 	htc->ar = ar;
856 
857 	/* Get HIF default pipe for HTC message exchange */
858 	ep = &htc->endpoint[ATH10K_HTC_EP_0];
859 
860 	ath10k_hif_set_callbacks(ar, &htc_callbacks);
861 	ath10k_hif_get_default_pipe(ar, &ep->ul_pipe_id, &ep->dl_pipe_id);
862 
863 	init_completion(&htc->ctl_resp);
864 
865 	return 0;
866 }
867