xref: /openbmc/linux/drivers/net/wireless/ath/ath10k/htc.c (revision bbde9fc1824aab58bc78c084163007dd6c03fe5b)
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 		goto err_credits;
150 
151 	sg_item.transfer_id = ep->eid;
152 	sg_item.transfer_context = skb;
153 	sg_item.vaddr = skb->data;
154 	sg_item.paddr = skb_cb->paddr;
155 	sg_item.len = skb->len;
156 
157 	ret = ath10k_hif_tx_sg(htc->ar, ep->ul_pipe_id, &sg_item, 1);
158 	if (ret)
159 		goto err_unmap;
160 
161 	return 0;
162 
163 err_unmap:
164 	dma_unmap_single(dev, skb_cb->paddr, skb->len, DMA_TO_DEVICE);
165 err_credits:
166 	if (ep->tx_credit_flow_enabled) {
167 		spin_lock_bh(&htc->tx_lock);
168 		ep->tx_credits += credits;
169 		ath10k_dbg(ar, ATH10K_DBG_HTC,
170 			   "htc ep %d reverted %d credits back (total %d)\n",
171 			   eid, credits, ep->tx_credits);
172 		spin_unlock_bh(&htc->tx_lock);
173 
174 		if (ep->ep_ops.ep_tx_credits)
175 			ep->ep_ops.ep_tx_credits(htc->ar);
176 	}
177 err_pull:
178 	skb_pull(skb, sizeof(struct ath10k_htc_hdr));
179 	return ret;
180 }
181 
182 static int ath10k_htc_tx_completion_handler(struct ath10k *ar,
183 					    struct sk_buff *skb)
184 {
185 	struct ath10k_htc *htc = &ar->htc;
186 	struct ath10k_skb_cb *skb_cb;
187 	struct ath10k_htc_ep *ep;
188 
189 	if (WARN_ON_ONCE(!skb))
190 		return 0;
191 
192 	skb_cb = ATH10K_SKB_CB(skb);
193 	ep = &htc->endpoint[skb_cb->eid];
194 
195 	ath10k_htc_notify_tx_completion(ep, skb);
196 	/* the skb now belongs to the completion handler */
197 
198 	return 0;
199 }
200 
201 /***********/
202 /* Receive */
203 /***********/
204 
205 static void
206 ath10k_htc_process_credit_report(struct ath10k_htc *htc,
207 				 const struct ath10k_htc_credit_report *report,
208 				 int len,
209 				 enum ath10k_htc_ep_id eid)
210 {
211 	struct ath10k *ar = htc->ar;
212 	struct ath10k_htc_ep *ep;
213 	int i, n_reports;
214 
215 	if (len % sizeof(*report))
216 		ath10k_warn(ar, "Uneven credit report len %d", len);
217 
218 	n_reports = len / sizeof(*report);
219 
220 	spin_lock_bh(&htc->tx_lock);
221 	for (i = 0; i < n_reports; i++, report++) {
222 		if (report->eid >= ATH10K_HTC_EP_COUNT)
223 			break;
224 
225 		ep = &htc->endpoint[report->eid];
226 		ep->tx_credits += report->credits;
227 
228 		ath10k_dbg(ar, ATH10K_DBG_HTC, "htc ep %d got %d credits (total %d)\n",
229 			   report->eid, report->credits, ep->tx_credits);
230 
231 		if (ep->ep_ops.ep_tx_credits) {
232 			spin_unlock_bh(&htc->tx_lock);
233 			ep->ep_ops.ep_tx_credits(htc->ar);
234 			spin_lock_bh(&htc->tx_lock);
235 		}
236 	}
237 	spin_unlock_bh(&htc->tx_lock);
238 }
239 
240 static int ath10k_htc_process_trailer(struct ath10k_htc *htc,
241 				      u8 *buffer,
242 				      int length,
243 				      enum ath10k_htc_ep_id src_eid)
244 {
245 	struct ath10k *ar = htc->ar;
246 	int status = 0;
247 	struct ath10k_htc_record *record;
248 	u8 *orig_buffer;
249 	int orig_length;
250 	size_t len;
251 
252 	orig_buffer = buffer;
253 	orig_length = length;
254 
255 	while (length > 0) {
256 		record = (struct ath10k_htc_record *)buffer;
257 
258 		if (length < sizeof(record->hdr)) {
259 			status = -EINVAL;
260 			break;
261 		}
262 
263 		if (record->hdr.len > length) {
264 			/* no room left in buffer for record */
265 			ath10k_warn(ar, "Invalid record length: %d\n",
266 				    record->hdr.len);
267 			status = -EINVAL;
268 			break;
269 		}
270 
271 		switch (record->hdr.id) {
272 		case ATH10K_HTC_RECORD_CREDITS:
273 			len = sizeof(struct ath10k_htc_credit_report);
274 			if (record->hdr.len < len) {
275 				ath10k_warn(ar, "Credit report too long\n");
276 				status = -EINVAL;
277 				break;
278 			}
279 			ath10k_htc_process_credit_report(htc,
280 							 record->credit_report,
281 							 record->hdr.len,
282 							 src_eid);
283 			break;
284 		default:
285 			ath10k_warn(ar, "Unhandled record: id:%d length:%d\n",
286 				    record->hdr.id, record->hdr.len);
287 			break;
288 		}
289 
290 		if (status)
291 			break;
292 
293 		/* multiple records may be present in a trailer */
294 		buffer += sizeof(record->hdr) + record->hdr.len;
295 		length -= sizeof(record->hdr) + record->hdr.len;
296 	}
297 
298 	if (status)
299 		ath10k_dbg_dump(ar, ATH10K_DBG_HTC, "htc rx bad trailer", "",
300 				orig_buffer, orig_length);
301 
302 	return status;
303 }
304 
305 static int ath10k_htc_rx_completion_handler(struct ath10k *ar,
306 					    struct sk_buff *skb)
307 {
308 	int status = 0;
309 	struct ath10k_htc *htc = &ar->htc;
310 	struct ath10k_htc_hdr *hdr;
311 	struct ath10k_htc_ep *ep;
312 	u16 payload_len;
313 	u32 trailer_len = 0;
314 	size_t min_len;
315 	u8 eid;
316 	bool trailer_present;
317 
318 	hdr = (struct ath10k_htc_hdr *)skb->data;
319 	skb_pull(skb, sizeof(*hdr));
320 
321 	eid = hdr->eid;
322 
323 	if (eid >= ATH10K_HTC_EP_COUNT) {
324 		ath10k_warn(ar, "HTC Rx: invalid eid %d\n", eid);
325 		ath10k_dbg_dump(ar, ATH10K_DBG_HTC, "htc bad header", "",
326 				hdr, sizeof(*hdr));
327 		status = -EINVAL;
328 		goto out;
329 	}
330 
331 	ep = &htc->endpoint[eid];
332 
333 	/*
334 	 * If this endpoint that received a message from the target has
335 	 * a to-target HIF pipe whose send completions are polled rather
336 	 * than interrupt-driven, this is a good point to ask HIF to check
337 	 * whether it has any completed sends to handle.
338 	 */
339 	if (ep->ul_is_polled)
340 		ath10k_htc_send_complete_check(ep, 1);
341 
342 	payload_len = __le16_to_cpu(hdr->len);
343 
344 	if (payload_len + sizeof(*hdr) > ATH10K_HTC_MAX_LEN) {
345 		ath10k_warn(ar, "HTC rx frame too long, len: %zu\n",
346 			    payload_len + sizeof(*hdr));
347 		ath10k_dbg_dump(ar, ATH10K_DBG_HTC, "htc bad rx pkt len", "",
348 				hdr, sizeof(*hdr));
349 		status = -EINVAL;
350 		goto out;
351 	}
352 
353 	if (skb->len < payload_len) {
354 		ath10k_dbg(ar, ATH10K_DBG_HTC,
355 			   "HTC Rx: insufficient length, got %d, expected %d\n",
356 			   skb->len, payload_len);
357 		ath10k_dbg_dump(ar, ATH10K_DBG_HTC, "htc bad rx pkt len",
358 				"", hdr, sizeof(*hdr));
359 		status = -EINVAL;
360 		goto out;
361 	}
362 
363 	/* get flags to check for trailer */
364 	trailer_present = hdr->flags & ATH10K_HTC_FLAG_TRAILER_PRESENT;
365 	if (trailer_present) {
366 		u8 *trailer;
367 
368 		trailer_len = hdr->trailer_len;
369 		min_len = sizeof(struct ath10k_ath10k_htc_record_hdr);
370 
371 		if ((trailer_len < min_len) ||
372 		    (trailer_len > payload_len)) {
373 			ath10k_warn(ar, "Invalid trailer length: %d\n",
374 				    trailer_len);
375 			status = -EPROTO;
376 			goto out;
377 		}
378 
379 		trailer = (u8 *)hdr;
380 		trailer += sizeof(*hdr);
381 		trailer += payload_len;
382 		trailer -= trailer_len;
383 		status = ath10k_htc_process_trailer(htc, trailer,
384 						    trailer_len, hdr->eid);
385 		if (status)
386 			goto out;
387 
388 		skb_trim(skb, skb->len - trailer_len);
389 	}
390 
391 	if (((int)payload_len - (int)trailer_len) <= 0)
392 		/* zero length packet with trailer data, just drop these */
393 		goto out;
394 
395 	if (eid == ATH10K_HTC_EP_0) {
396 		struct ath10k_htc_msg *msg = (struct ath10k_htc_msg *)skb->data;
397 
398 		switch (__le16_to_cpu(msg->hdr.message_id)) {
399 		case ATH10K_HTC_MSG_READY_ID:
400 		case ATH10K_HTC_MSG_CONNECT_SERVICE_RESP_ID:
401 			/* handle HTC control message */
402 			if (completion_done(&htc->ctl_resp)) {
403 				/*
404 				 * this is a fatal error, target should not be
405 				 * sending unsolicited messages on the ep 0
406 				 */
407 				ath10k_warn(ar, "HTC rx ctrl still processing\n");
408 				status = -EINVAL;
409 				complete(&htc->ctl_resp);
410 				goto out;
411 			}
412 
413 			htc->control_resp_len =
414 				min_t(int, skb->len,
415 				      ATH10K_HTC_MAX_CTRL_MSG_LEN);
416 
417 			memcpy(htc->control_resp_buffer, skb->data,
418 			       htc->control_resp_len);
419 
420 			complete(&htc->ctl_resp);
421 			break;
422 		case ATH10K_HTC_MSG_SEND_SUSPEND_COMPLETE:
423 			htc->htc_ops.target_send_suspend_complete(ar);
424 			break;
425 		default:
426 			ath10k_warn(ar, "ignoring unsolicited htc ep0 event\n");
427 			break;
428 		}
429 		goto out;
430 	}
431 
432 	ath10k_dbg(ar, ATH10K_DBG_HTC, "htc rx completion ep %d skb %p\n",
433 		   eid, skb);
434 	ep->ep_ops.ep_rx_complete(ar, skb);
435 
436 	/* skb is now owned by the rx completion handler */
437 	skb = NULL;
438 out:
439 	kfree_skb(skb);
440 
441 	return status;
442 }
443 
444 static void ath10k_htc_control_rx_complete(struct ath10k *ar,
445 					   struct sk_buff *skb)
446 {
447 	/* This is unexpected. FW is not supposed to send regular rx on this
448 	 * endpoint. */
449 	ath10k_warn(ar, "unexpected htc rx\n");
450 	kfree_skb(skb);
451 }
452 
453 /***************/
454 /* Init/Deinit */
455 /***************/
456 
457 static const char *htc_service_name(enum ath10k_htc_svc_id id)
458 {
459 	switch (id) {
460 	case ATH10K_HTC_SVC_ID_RESERVED:
461 		return "Reserved";
462 	case ATH10K_HTC_SVC_ID_RSVD_CTRL:
463 		return "Control";
464 	case ATH10K_HTC_SVC_ID_WMI_CONTROL:
465 		return "WMI";
466 	case ATH10K_HTC_SVC_ID_WMI_DATA_BE:
467 		return "DATA BE";
468 	case ATH10K_HTC_SVC_ID_WMI_DATA_BK:
469 		return "DATA BK";
470 	case ATH10K_HTC_SVC_ID_WMI_DATA_VI:
471 		return "DATA VI";
472 	case ATH10K_HTC_SVC_ID_WMI_DATA_VO:
473 		return "DATA VO";
474 	case ATH10K_HTC_SVC_ID_NMI_CONTROL:
475 		return "NMI Control";
476 	case ATH10K_HTC_SVC_ID_NMI_DATA:
477 		return "NMI Data";
478 	case ATH10K_HTC_SVC_ID_HTT_DATA_MSG:
479 		return "HTT Data";
480 	case ATH10K_HTC_SVC_ID_TEST_RAW_STREAMS:
481 		return "RAW";
482 	}
483 
484 	return "Unknown";
485 }
486 
487 static void ath10k_htc_reset_endpoint_states(struct ath10k_htc *htc)
488 {
489 	struct ath10k_htc_ep *ep;
490 	int i;
491 
492 	for (i = ATH10K_HTC_EP_0; i < ATH10K_HTC_EP_COUNT; i++) {
493 		ep = &htc->endpoint[i];
494 		ep->service_id = ATH10K_HTC_SVC_ID_UNUSED;
495 		ep->max_ep_message_len = 0;
496 		ep->max_tx_queue_depth = 0;
497 		ep->eid = i;
498 		ep->htc = htc;
499 		ep->tx_credit_flow_enabled = true;
500 	}
501 }
502 
503 static void ath10k_htc_setup_target_buffer_assignments(struct ath10k_htc *htc)
504 {
505 	struct ath10k_htc_svc_tx_credits *entry;
506 
507 	entry = &htc->service_tx_alloc[0];
508 
509 	/*
510 	 * for PCIE allocate all credists/HTC buffers to WMI.
511 	 * no buffers are used/required for data. data always
512 	 * remains on host.
513 	 */
514 	entry++;
515 	entry->service_id = ATH10K_HTC_SVC_ID_WMI_CONTROL;
516 	entry->credit_allocation = htc->total_transmit_credits;
517 }
518 
519 static u8 ath10k_htc_get_credit_allocation(struct ath10k_htc *htc,
520 					   u16 service_id)
521 {
522 	u8 allocation = 0;
523 	int i;
524 
525 	for (i = 0; i < ATH10K_HTC_EP_COUNT; i++) {
526 		if (htc->service_tx_alloc[i].service_id == service_id)
527 			allocation =
528 			    htc->service_tx_alloc[i].credit_allocation;
529 	}
530 
531 	return allocation;
532 }
533 
534 int ath10k_htc_wait_target(struct ath10k_htc *htc)
535 {
536 	struct ath10k *ar = htc->ar;
537 	int i, status = 0;
538 	unsigned long time_left;
539 	struct ath10k_htc_svc_conn_req conn_req;
540 	struct ath10k_htc_svc_conn_resp conn_resp;
541 	struct ath10k_htc_msg *msg;
542 	u16 message_id;
543 	u16 credit_count;
544 	u16 credit_size;
545 
546 	time_left = wait_for_completion_timeout(&htc->ctl_resp,
547 						ATH10K_HTC_WAIT_TIMEOUT_HZ);
548 	if (!time_left) {
549 		/* Workaround: In some cases the PCI HIF doesn't
550 		 * receive interrupt for the control response message
551 		 * even if the buffer was completed. It is suspected
552 		 * iomap writes unmasking PCI CE irqs aren't propagated
553 		 * properly in KVM PCI-passthrough sometimes.
554 		 */
555 		ath10k_warn(ar, "failed to receive control response completion, polling..\n");
556 
557 		for (i = 0; i < CE_COUNT; i++)
558 			ath10k_hif_send_complete_check(htc->ar, i, 1);
559 
560 		time_left =
561 		wait_for_completion_timeout(&htc->ctl_resp,
562 					    ATH10K_HTC_WAIT_TIMEOUT_HZ);
563 
564 		if (!time_left)
565 			status = -ETIMEDOUT;
566 	}
567 
568 	if (status < 0) {
569 		ath10k_err(ar, "ctl_resp never came in (%d)\n", status);
570 		return status;
571 	}
572 
573 	if (htc->control_resp_len < sizeof(msg->hdr) + sizeof(msg->ready)) {
574 		ath10k_err(ar, "Invalid HTC ready msg len:%d\n",
575 			   htc->control_resp_len);
576 		return -ECOMM;
577 	}
578 
579 	msg = (struct ath10k_htc_msg *)htc->control_resp_buffer;
580 	message_id   = __le16_to_cpu(msg->hdr.message_id);
581 	credit_count = __le16_to_cpu(msg->ready.credit_count);
582 	credit_size  = __le16_to_cpu(msg->ready.credit_size);
583 
584 	if (message_id != ATH10K_HTC_MSG_READY_ID) {
585 		ath10k_err(ar, "Invalid HTC ready msg: 0x%x\n", message_id);
586 		return -ECOMM;
587 	}
588 
589 	htc->total_transmit_credits = credit_count;
590 	htc->target_credit_size = credit_size;
591 
592 	ath10k_dbg(ar, ATH10K_DBG_HTC,
593 		   "Target ready! transmit resources: %d size:%d\n",
594 		   htc->total_transmit_credits,
595 		   htc->target_credit_size);
596 
597 	if ((htc->total_transmit_credits == 0) ||
598 	    (htc->target_credit_size == 0)) {
599 		ath10k_err(ar, "Invalid credit size received\n");
600 		return -ECOMM;
601 	}
602 
603 	ath10k_htc_setup_target_buffer_assignments(htc);
604 
605 	/* setup our pseudo HTC control endpoint connection */
606 	memset(&conn_req, 0, sizeof(conn_req));
607 	memset(&conn_resp, 0, sizeof(conn_resp));
608 	conn_req.ep_ops.ep_tx_complete = ath10k_htc_control_tx_complete;
609 	conn_req.ep_ops.ep_rx_complete = ath10k_htc_control_rx_complete;
610 	conn_req.max_send_queue_depth = ATH10K_NUM_CONTROL_TX_BUFFERS;
611 	conn_req.service_id = ATH10K_HTC_SVC_ID_RSVD_CTRL;
612 
613 	/* connect fake service */
614 	status = ath10k_htc_connect_service(htc, &conn_req, &conn_resp);
615 	if (status) {
616 		ath10k_err(ar, "could not connect to htc service (%d)\n",
617 			   status);
618 		return status;
619 	}
620 
621 	return 0;
622 }
623 
624 int ath10k_htc_connect_service(struct ath10k_htc *htc,
625 			       struct ath10k_htc_svc_conn_req *conn_req,
626 			       struct ath10k_htc_svc_conn_resp *conn_resp)
627 {
628 	struct ath10k *ar = htc->ar;
629 	struct ath10k_htc_msg *msg;
630 	struct ath10k_htc_conn_svc *req_msg;
631 	struct ath10k_htc_conn_svc_response resp_msg_dummy;
632 	struct ath10k_htc_conn_svc_response *resp_msg = &resp_msg_dummy;
633 	enum ath10k_htc_ep_id assigned_eid = ATH10K_HTC_EP_COUNT;
634 	struct ath10k_htc_ep *ep;
635 	struct sk_buff *skb;
636 	unsigned int max_msg_size = 0;
637 	int length, status;
638 	unsigned long time_left;
639 	bool disable_credit_flow_ctrl = false;
640 	u16 message_id, service_id, flags = 0;
641 	u8 tx_alloc = 0;
642 
643 	/* special case for HTC pseudo control service */
644 	if (conn_req->service_id == ATH10K_HTC_SVC_ID_RSVD_CTRL) {
645 		disable_credit_flow_ctrl = true;
646 		assigned_eid = ATH10K_HTC_EP_0;
647 		max_msg_size = ATH10K_HTC_MAX_CTRL_MSG_LEN;
648 		memset(&resp_msg_dummy, 0, sizeof(resp_msg_dummy));
649 		goto setup;
650 	}
651 
652 	tx_alloc = ath10k_htc_get_credit_allocation(htc,
653 						    conn_req->service_id);
654 	if (!tx_alloc)
655 		ath10k_dbg(ar, ATH10K_DBG_BOOT,
656 			   "boot htc service %s does not allocate target credits\n",
657 			   htc_service_name(conn_req->service_id));
658 
659 	skb = ath10k_htc_build_tx_ctrl_skb(htc->ar);
660 	if (!skb) {
661 		ath10k_err(ar, "Failed to allocate HTC packet\n");
662 		return -ENOMEM;
663 	}
664 
665 	length = sizeof(msg->hdr) + sizeof(msg->connect_service);
666 	skb_put(skb, length);
667 	memset(skb->data, 0, length);
668 
669 	msg = (struct ath10k_htc_msg *)skb->data;
670 	msg->hdr.message_id =
671 		__cpu_to_le16(ATH10K_HTC_MSG_CONNECT_SERVICE_ID);
672 
673 	flags |= SM(tx_alloc, ATH10K_HTC_CONN_FLAGS_RECV_ALLOC);
674 
675 	/* Only enable credit flow control for WMI ctrl service */
676 	if (conn_req->service_id != ATH10K_HTC_SVC_ID_WMI_CONTROL) {
677 		flags |= ATH10K_HTC_CONN_FLAGS_DISABLE_CREDIT_FLOW_CTRL;
678 		disable_credit_flow_ctrl = true;
679 	}
680 
681 	req_msg = &msg->connect_service;
682 	req_msg->flags = __cpu_to_le16(flags);
683 	req_msg->service_id = __cpu_to_le16(conn_req->service_id);
684 
685 	reinit_completion(&htc->ctl_resp);
686 
687 	status = ath10k_htc_send(htc, ATH10K_HTC_EP_0, skb);
688 	if (status) {
689 		kfree_skb(skb);
690 		return status;
691 	}
692 
693 	/* wait for response */
694 	time_left = wait_for_completion_timeout(&htc->ctl_resp,
695 						ATH10K_HTC_CONN_SVC_TIMEOUT_HZ);
696 	if (!time_left) {
697 		ath10k_err(ar, "Service connect timeout\n");
698 		return -ETIMEDOUT;
699 	}
700 
701 	/* we controlled the buffer creation, it's aligned */
702 	msg = (struct ath10k_htc_msg *)htc->control_resp_buffer;
703 	resp_msg = &msg->connect_service_response;
704 	message_id = __le16_to_cpu(msg->hdr.message_id);
705 	service_id = __le16_to_cpu(resp_msg->service_id);
706 
707 	if ((message_id != ATH10K_HTC_MSG_CONNECT_SERVICE_RESP_ID) ||
708 	    (htc->control_resp_len < sizeof(msg->hdr) +
709 	     sizeof(msg->connect_service_response))) {
710 		ath10k_err(ar, "Invalid resp message ID 0x%x", message_id);
711 		return -EPROTO;
712 	}
713 
714 	ath10k_dbg(ar, ATH10K_DBG_HTC,
715 		   "HTC Service %s connect response: status: 0x%x, assigned ep: 0x%x\n",
716 		   htc_service_name(service_id),
717 		   resp_msg->status, resp_msg->eid);
718 
719 	conn_resp->connect_resp_code = resp_msg->status;
720 
721 	/* check response status */
722 	if (resp_msg->status != ATH10K_HTC_CONN_SVC_STATUS_SUCCESS) {
723 		ath10k_err(ar, "HTC Service %s connect request failed: 0x%x)\n",
724 			   htc_service_name(service_id),
725 			   resp_msg->status);
726 		return -EPROTO;
727 	}
728 
729 	assigned_eid = (enum ath10k_htc_ep_id)resp_msg->eid;
730 	max_msg_size = __le16_to_cpu(resp_msg->max_msg_size);
731 
732 setup:
733 
734 	if (assigned_eid >= ATH10K_HTC_EP_COUNT)
735 		return -EPROTO;
736 
737 	if (max_msg_size == 0)
738 		return -EPROTO;
739 
740 	ep = &htc->endpoint[assigned_eid];
741 	ep->eid = assigned_eid;
742 
743 	if (ep->service_id != ATH10K_HTC_SVC_ID_UNUSED)
744 		return -EPROTO;
745 
746 	/* return assigned endpoint to caller */
747 	conn_resp->eid = assigned_eid;
748 	conn_resp->max_msg_len = __le16_to_cpu(resp_msg->max_msg_size);
749 
750 	/* setup the endpoint */
751 	ep->service_id = conn_req->service_id;
752 	ep->max_tx_queue_depth = conn_req->max_send_queue_depth;
753 	ep->max_ep_message_len = __le16_to_cpu(resp_msg->max_msg_size);
754 	ep->tx_credits = tx_alloc;
755 	ep->tx_credit_size = htc->target_credit_size;
756 	ep->tx_credits_per_max_message = ep->max_ep_message_len /
757 					 htc->target_credit_size;
758 
759 	if (ep->max_ep_message_len % htc->target_credit_size)
760 		ep->tx_credits_per_max_message++;
761 
762 	/* copy all the callbacks */
763 	ep->ep_ops = conn_req->ep_ops;
764 
765 	status = ath10k_hif_map_service_to_pipe(htc->ar,
766 						ep->service_id,
767 						&ep->ul_pipe_id,
768 						&ep->dl_pipe_id,
769 						&ep->ul_is_polled,
770 						&ep->dl_is_polled);
771 	if (status)
772 		return status;
773 
774 	ath10k_dbg(ar, ATH10K_DBG_BOOT,
775 		   "boot htc service '%s' ul pipe %d dl pipe %d eid %d ready\n",
776 		   htc_service_name(ep->service_id), ep->ul_pipe_id,
777 		   ep->dl_pipe_id, ep->eid);
778 
779 	ath10k_dbg(ar, ATH10K_DBG_BOOT,
780 		   "boot htc ep %d ul polled %d dl polled %d\n",
781 		   ep->eid, ep->ul_is_polled, ep->dl_is_polled);
782 
783 	if (disable_credit_flow_ctrl && ep->tx_credit_flow_enabled) {
784 		ep->tx_credit_flow_enabled = false;
785 		ath10k_dbg(ar, ATH10K_DBG_BOOT,
786 			   "boot htc service '%s' eid %d TX flow control disabled\n",
787 			   htc_service_name(ep->service_id), assigned_eid);
788 	}
789 
790 	return status;
791 }
792 
793 struct sk_buff *ath10k_htc_alloc_skb(struct ath10k *ar, int size)
794 {
795 	struct sk_buff *skb;
796 
797 	skb = dev_alloc_skb(size + sizeof(struct ath10k_htc_hdr));
798 	if (!skb)
799 		return NULL;
800 
801 	skb_reserve(skb, sizeof(struct ath10k_htc_hdr));
802 
803 	/* FW/HTC requires 4-byte aligned streams */
804 	if (!IS_ALIGNED((unsigned long)skb->data, 4))
805 		ath10k_warn(ar, "Unaligned HTC tx skb\n");
806 
807 	return skb;
808 }
809 
810 int ath10k_htc_start(struct ath10k_htc *htc)
811 {
812 	struct ath10k *ar = htc->ar;
813 	struct sk_buff *skb;
814 	int status = 0;
815 	struct ath10k_htc_msg *msg;
816 
817 	skb = ath10k_htc_build_tx_ctrl_skb(htc->ar);
818 	if (!skb)
819 		return -ENOMEM;
820 
821 	skb_put(skb, sizeof(msg->hdr) + sizeof(msg->setup_complete_ext));
822 	memset(skb->data, 0, skb->len);
823 
824 	msg = (struct ath10k_htc_msg *)skb->data;
825 	msg->hdr.message_id =
826 		__cpu_to_le16(ATH10K_HTC_MSG_SETUP_COMPLETE_EX_ID);
827 
828 	ath10k_dbg(ar, ATH10K_DBG_HTC, "HTC is using TX credit flow control\n");
829 
830 	status = ath10k_htc_send(htc, ATH10K_HTC_EP_0, skb);
831 	if (status) {
832 		kfree_skb(skb);
833 		return status;
834 	}
835 
836 	return 0;
837 }
838 
839 /* registered target arrival callback from the HIF layer */
840 int ath10k_htc_init(struct ath10k *ar)
841 {
842 	struct ath10k_hif_cb htc_callbacks;
843 	struct ath10k_htc_ep *ep = NULL;
844 	struct ath10k_htc *htc = &ar->htc;
845 
846 	spin_lock_init(&htc->tx_lock);
847 
848 	ath10k_htc_reset_endpoint_states(htc);
849 
850 	/* setup HIF layer callbacks */
851 	htc_callbacks.rx_completion = ath10k_htc_rx_completion_handler;
852 	htc_callbacks.tx_completion = ath10k_htc_tx_completion_handler;
853 	htc->ar = ar;
854 
855 	/* Get HIF default pipe for HTC message exchange */
856 	ep = &htc->endpoint[ATH10K_HTC_EP_0];
857 
858 	ath10k_hif_set_callbacks(ar, &htc_callbacks);
859 	ath10k_hif_get_default_pipe(ar, &ep->ul_pipe_id, &ep->dl_pipe_id);
860 
861 	init_completion(&htc->ctl_resp);
862 
863 	return 0;
864 }
865