xref: /openbmc/linux/drivers/net/wireless/ath/ath10k/htc.c (revision 12eb4683)
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 
107 	hdr->eid = ep->eid;
108 	hdr->len = __cpu_to_le16(skb->len - sizeof(*hdr));
109 	hdr->flags = 0;
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 int ath10k_htc_send(struct ath10k_htc *htc,
121 		    enum ath10k_htc_ep_id eid,
122 		    struct sk_buff *skb)
123 {
124 	struct ath10k_htc_ep *ep = &htc->endpoint[eid];
125 	int credits = 0;
126 	int ret;
127 
128 	if (htc->ar->state == ATH10K_STATE_WEDGED)
129 		return -ECOMM;
130 
131 	if (eid >= ATH10K_HTC_EP_COUNT) {
132 		ath10k_warn("Invalid endpoint id: %d\n", eid);
133 		return -ENOENT;
134 	}
135 
136 	/* FIXME: This looks ugly, can we fix it? */
137 	spin_lock_bh(&htc->tx_lock);
138 	if (htc->stopped) {
139 		spin_unlock_bh(&htc->tx_lock);
140 		return -ESHUTDOWN;
141 	}
142 	spin_unlock_bh(&htc->tx_lock);
143 
144 	skb_push(skb, sizeof(struct ath10k_htc_hdr));
145 
146 	if (ep->tx_credit_flow_enabled) {
147 		credits = DIV_ROUND_UP(skb->len, htc->target_credit_size);
148 		spin_lock_bh(&htc->tx_lock);
149 		if (ep->tx_credits < credits) {
150 			spin_unlock_bh(&htc->tx_lock);
151 			ret = -EAGAIN;
152 			goto err_pull;
153 		}
154 		ep->tx_credits -= credits;
155 		spin_unlock_bh(&htc->tx_lock);
156 	}
157 
158 	ath10k_htc_prepare_tx_skb(ep, skb);
159 
160 	ret = ath10k_skb_map(htc->ar->dev, skb);
161 	if (ret)
162 		goto err_credits;
163 
164 	ret = ath10k_hif_send_head(htc->ar, ep->ul_pipe_id, ep->eid,
165 				   skb->len, skb);
166 	if (ret)
167 		goto err_unmap;
168 
169 	return 0;
170 
171 err_unmap:
172 	ath10k_skb_unmap(htc->ar->dev, skb);
173 err_credits:
174 	if (ep->tx_credit_flow_enabled) {
175 		spin_lock_bh(&htc->tx_lock);
176 		ep->tx_credits += credits;
177 		spin_unlock_bh(&htc->tx_lock);
178 
179 		if (ep->ep_ops.ep_tx_credits)
180 			ep->ep_ops.ep_tx_credits(htc->ar);
181 	}
182 err_pull:
183 	skb_pull(skb, sizeof(struct ath10k_htc_hdr));
184 	return ret;
185 }
186 
187 static int ath10k_htc_tx_completion_handler(struct ath10k *ar,
188 					    struct sk_buff *skb,
189 					    unsigned int eid)
190 {
191 	struct ath10k_htc *htc = &ar->htc;
192 	struct ath10k_htc_ep *ep = &htc->endpoint[eid];
193 
194 	ath10k_htc_notify_tx_completion(ep, skb);
195 	/* the skb now belongs to the completion handler */
196 
197 	return 0;
198 }
199 
200 /***********/
201 /* Receive */
202 /***********/
203 
204 static void
205 ath10k_htc_process_credit_report(struct ath10k_htc *htc,
206 				 const struct ath10k_htc_credit_report *report,
207 				 int len,
208 				 enum ath10k_htc_ep_id eid)
209 {
210 	struct ath10k_htc_ep *ep;
211 	int i, n_reports;
212 
213 	if (len % sizeof(*report))
214 		ath10k_warn("Uneven credit report len %d", len);
215 
216 	n_reports = len / sizeof(*report);
217 
218 	spin_lock_bh(&htc->tx_lock);
219 	for (i = 0; i < n_reports; i++, report++) {
220 		if (report->eid >= ATH10K_HTC_EP_COUNT)
221 			break;
222 
223 		ath10k_dbg(ATH10K_DBG_HTC, "ep %d got %d credits\n",
224 			   report->eid, report->credits);
225 
226 		ep = &htc->endpoint[report->eid];
227 		ep->tx_credits += report->credits;
228 
229 		if (ep->ep_ops.ep_tx_credits) {
230 			spin_unlock_bh(&htc->tx_lock);
231 			ep->ep_ops.ep_tx_credits(htc->ar);
232 			spin_lock_bh(&htc->tx_lock);
233 		}
234 	}
235 	spin_unlock_bh(&htc->tx_lock);
236 }
237 
238 static int ath10k_htc_process_trailer(struct ath10k_htc *htc,
239 				      u8 *buffer,
240 				      int length,
241 				      enum ath10k_htc_ep_id src_eid)
242 {
243 	int status = 0;
244 	struct ath10k_htc_record *record;
245 	u8 *orig_buffer;
246 	int orig_length;
247 	size_t len;
248 
249 	orig_buffer = buffer;
250 	orig_length = length;
251 
252 	while (length > 0) {
253 		record = (struct ath10k_htc_record *)buffer;
254 
255 		if (length < sizeof(record->hdr)) {
256 			status = -EINVAL;
257 			break;
258 		}
259 
260 		if (record->hdr.len > length) {
261 			/* no room left in buffer for record */
262 			ath10k_warn("Invalid record length: %d\n",
263 				    record->hdr.len);
264 			status = -EINVAL;
265 			break;
266 		}
267 
268 		switch (record->hdr.id) {
269 		case ATH10K_HTC_RECORD_CREDITS:
270 			len = sizeof(struct ath10k_htc_credit_report);
271 			if (record->hdr.len < len) {
272 				ath10k_warn("Credit report too long\n");
273 				status = -EINVAL;
274 				break;
275 			}
276 			ath10k_htc_process_credit_report(htc,
277 							 record->credit_report,
278 							 record->hdr.len,
279 							 src_eid);
280 			break;
281 		default:
282 			ath10k_warn("Unhandled record: id:%d length:%d\n",
283 				    record->hdr.id, record->hdr.len);
284 			break;
285 		}
286 
287 		if (status)
288 			break;
289 
290 		/* multiple records may be present in a trailer */
291 		buffer += sizeof(record->hdr) + record->hdr.len;
292 		length -= sizeof(record->hdr) + record->hdr.len;
293 	}
294 
295 	if (status)
296 		ath10k_dbg_dump(ATH10K_DBG_HTC, "htc rx bad trailer", "",
297 				orig_buffer, orig_length);
298 
299 	return status;
300 }
301 
302 static int ath10k_htc_rx_completion_handler(struct ath10k *ar,
303 					    struct sk_buff *skb,
304 					    u8 pipe_id)
305 {
306 	int status = 0;
307 	struct ath10k_htc *htc = &ar->htc;
308 	struct ath10k_htc_hdr *hdr;
309 	struct ath10k_htc_ep *ep;
310 	u16 payload_len;
311 	u32 trailer_len = 0;
312 	size_t min_len;
313 	u8 eid;
314 	bool trailer_present;
315 
316 	hdr = (struct ath10k_htc_hdr *)skb->data;
317 	skb_pull(skb, sizeof(*hdr));
318 
319 	eid = hdr->eid;
320 
321 	if (eid >= ATH10K_HTC_EP_COUNT) {
322 		ath10k_warn("HTC Rx: invalid eid %d\n", eid);
323 		ath10k_dbg_dump(ATH10K_DBG_HTC, "htc bad header", "",
324 				hdr, sizeof(*hdr));
325 		status = -EINVAL;
326 		goto out;
327 	}
328 
329 	ep = &htc->endpoint[eid];
330 
331 	/*
332 	 * If this endpoint that received a message from the target has
333 	 * a to-target HIF pipe whose send completions are polled rather
334 	 * than interrupt-driven, this is a good point to ask HIF to check
335 	 * whether it has any completed sends to handle.
336 	 */
337 	if (ep->ul_is_polled)
338 		ath10k_htc_send_complete_check(ep, 1);
339 
340 	payload_len = __le16_to_cpu(hdr->len);
341 
342 	if (payload_len + sizeof(*hdr) > ATH10K_HTC_MAX_LEN) {
343 		ath10k_warn("HTC rx frame too long, len: %zu\n",
344 			    payload_len + sizeof(*hdr));
345 		ath10k_dbg_dump(ATH10K_DBG_HTC, "htc bad rx pkt len", "",
346 				hdr, sizeof(*hdr));
347 		status = -EINVAL;
348 		goto out;
349 	}
350 
351 	if (skb->len < payload_len) {
352 		ath10k_dbg(ATH10K_DBG_HTC,
353 			   "HTC Rx: insufficient length, got %d, expected %d\n",
354 			   skb->len, payload_len);
355 		ath10k_dbg_dump(ATH10K_DBG_HTC, "htc bad rx pkt len",
356 				"", hdr, sizeof(*hdr));
357 		status = -EINVAL;
358 		goto out;
359 	}
360 
361 	/* get flags to check for trailer */
362 	trailer_present = hdr->flags & ATH10K_HTC_FLAG_TRAILER_PRESENT;
363 	if (trailer_present) {
364 		u8 *trailer;
365 
366 		trailer_len = hdr->trailer_len;
367 		min_len = sizeof(struct ath10k_ath10k_htc_record_hdr);
368 
369 		if ((trailer_len < min_len) ||
370 		    (trailer_len > payload_len)) {
371 			ath10k_warn("Invalid trailer length: %d\n",
372 				    trailer_len);
373 			status = -EPROTO;
374 			goto out;
375 		}
376 
377 		trailer = (u8 *)hdr;
378 		trailer += sizeof(*hdr);
379 		trailer += payload_len;
380 		trailer -= trailer_len;
381 		status = ath10k_htc_process_trailer(htc, trailer,
382 						    trailer_len, hdr->eid);
383 		if (status)
384 			goto out;
385 
386 		skb_trim(skb, skb->len - trailer_len);
387 	}
388 
389 	if (((int)payload_len - (int)trailer_len) <= 0)
390 		/* zero length packet with trailer data, just drop these */
391 		goto out;
392 
393 	if (eid == ATH10K_HTC_EP_0) {
394 		struct ath10k_htc_msg *msg = (struct ath10k_htc_msg *)skb->data;
395 
396 		switch (__le16_to_cpu(msg->hdr.message_id)) {
397 		default:
398 			/* handle HTC control message */
399 			if (completion_done(&htc->ctl_resp)) {
400 				/*
401 				 * this is a fatal error, target should not be
402 				 * sending unsolicited messages on the ep 0
403 				 */
404 				ath10k_warn("HTC rx ctrl still processing\n");
405 				status = -EINVAL;
406 				complete(&htc->ctl_resp);
407 				goto out;
408 			}
409 
410 			htc->control_resp_len =
411 				min_t(int, skb->len,
412 				      ATH10K_HTC_MAX_CTRL_MSG_LEN);
413 
414 			memcpy(htc->control_resp_buffer, skb->data,
415 			       htc->control_resp_len);
416 
417 			complete(&htc->ctl_resp);
418 			break;
419 		case ATH10K_HTC_MSG_SEND_SUSPEND_COMPLETE:
420 			htc->htc_ops.target_send_suspend_complete(ar);
421 		}
422 		goto out;
423 	}
424 
425 	ath10k_dbg(ATH10K_DBG_HTC, "htc rx completion ep %d skb %p\n",
426 		   eid, skb);
427 	ep->ep_ops.ep_rx_complete(ar, skb);
428 
429 	/* skb is now owned by the rx completion handler */
430 	skb = NULL;
431 out:
432 	kfree_skb(skb);
433 
434 	return status;
435 }
436 
437 static void ath10k_htc_control_rx_complete(struct ath10k *ar,
438 					   struct sk_buff *skb)
439 {
440 	/* This is unexpected. FW is not supposed to send regular rx on this
441 	 * endpoint. */
442 	ath10k_warn("unexpected htc rx\n");
443 	kfree_skb(skb);
444 }
445 
446 /***************/
447 /* Init/Deinit */
448 /***************/
449 
450 static const char *htc_service_name(enum ath10k_htc_svc_id id)
451 {
452 	switch (id) {
453 	case ATH10K_HTC_SVC_ID_RESERVED:
454 		return "Reserved";
455 	case ATH10K_HTC_SVC_ID_RSVD_CTRL:
456 		return "Control";
457 	case ATH10K_HTC_SVC_ID_WMI_CONTROL:
458 		return "WMI";
459 	case ATH10K_HTC_SVC_ID_WMI_DATA_BE:
460 		return "DATA BE";
461 	case ATH10K_HTC_SVC_ID_WMI_DATA_BK:
462 		return "DATA BK";
463 	case ATH10K_HTC_SVC_ID_WMI_DATA_VI:
464 		return "DATA VI";
465 	case ATH10K_HTC_SVC_ID_WMI_DATA_VO:
466 		return "DATA VO";
467 	case ATH10K_HTC_SVC_ID_NMI_CONTROL:
468 		return "NMI Control";
469 	case ATH10K_HTC_SVC_ID_NMI_DATA:
470 		return "NMI Data";
471 	case ATH10K_HTC_SVC_ID_HTT_DATA_MSG:
472 		return "HTT Data";
473 	case ATH10K_HTC_SVC_ID_TEST_RAW_STREAMS:
474 		return "RAW";
475 	}
476 
477 	return "Unknown";
478 }
479 
480 static void ath10k_htc_reset_endpoint_states(struct ath10k_htc *htc)
481 {
482 	struct ath10k_htc_ep *ep;
483 	int i;
484 
485 	for (i = ATH10K_HTC_EP_0; i < ATH10K_HTC_EP_COUNT; i++) {
486 		ep = &htc->endpoint[i];
487 		ep->service_id = ATH10K_HTC_SVC_ID_UNUSED;
488 		ep->max_ep_message_len = 0;
489 		ep->max_tx_queue_depth = 0;
490 		ep->eid = i;
491 		ep->htc = htc;
492 		ep->tx_credit_flow_enabled = true;
493 	}
494 }
495 
496 static void ath10k_htc_setup_target_buffer_assignments(struct ath10k_htc *htc)
497 {
498 	struct ath10k_htc_svc_tx_credits *entry;
499 
500 	entry = &htc->service_tx_alloc[0];
501 
502 	/*
503 	 * for PCIE allocate all credists/HTC buffers to WMI.
504 	 * no buffers are used/required for data. data always
505 	 * remains on host.
506 	 */
507 	entry++;
508 	entry->service_id = ATH10K_HTC_SVC_ID_WMI_CONTROL;
509 	entry->credit_allocation = htc->total_transmit_credits;
510 }
511 
512 static u8 ath10k_htc_get_credit_allocation(struct ath10k_htc *htc,
513 					   u16 service_id)
514 {
515 	u8 allocation = 0;
516 	int i;
517 
518 	for (i = 0; i < ATH10K_HTC_EP_COUNT; i++) {
519 		if (htc->service_tx_alloc[i].service_id == service_id)
520 			allocation =
521 			    htc->service_tx_alloc[i].credit_allocation;
522 	}
523 
524 	return allocation;
525 }
526 
527 int ath10k_htc_wait_target(struct ath10k_htc *htc)
528 {
529 	int status = 0;
530 	struct ath10k_htc_svc_conn_req conn_req;
531 	struct ath10k_htc_svc_conn_resp conn_resp;
532 	struct ath10k_htc_msg *msg;
533 	u16 message_id;
534 	u16 credit_count;
535 	u16 credit_size;
536 
537 	reinit_completion(&htc->ctl_resp);
538 
539 	status = ath10k_hif_start(htc->ar);
540 	if (status) {
541 		ath10k_err("could not start HIF (%d)\n", status);
542 		goto err_start;
543 	}
544 
545 	status = wait_for_completion_timeout(&htc->ctl_resp,
546 					     ATH10K_HTC_WAIT_TIMEOUT_HZ);
547 	if (status <= 0) {
548 		if (status == 0)
549 			status = -ETIMEDOUT;
550 
551 		ath10k_err("ctl_resp never came in (%d)\n", status);
552 		goto err_target;
553 	}
554 
555 	if (htc->control_resp_len < sizeof(msg->hdr) + sizeof(msg->ready)) {
556 		ath10k_err("Invalid HTC ready msg len:%d\n",
557 			   htc->control_resp_len);
558 
559 		status = -ECOMM;
560 		goto err_target;
561 	}
562 
563 	msg = (struct ath10k_htc_msg *)htc->control_resp_buffer;
564 	message_id   = __le16_to_cpu(msg->hdr.message_id);
565 	credit_count = __le16_to_cpu(msg->ready.credit_count);
566 	credit_size  = __le16_to_cpu(msg->ready.credit_size);
567 
568 	if (message_id != ATH10K_HTC_MSG_READY_ID) {
569 		ath10k_err("Invalid HTC ready msg: 0x%x\n", message_id);
570 		status = -ECOMM;
571 		goto err_target;
572 	}
573 
574 	htc->total_transmit_credits = credit_count;
575 	htc->target_credit_size = credit_size;
576 
577 	ath10k_dbg(ATH10K_DBG_HTC,
578 		   "Target ready! transmit resources: %d size:%d\n",
579 		   htc->total_transmit_credits,
580 		   htc->target_credit_size);
581 
582 	if ((htc->total_transmit_credits == 0) ||
583 	    (htc->target_credit_size == 0)) {
584 		status = -ECOMM;
585 		ath10k_err("Invalid credit size received\n");
586 		goto err_target;
587 	}
588 
589 	ath10k_htc_setup_target_buffer_assignments(htc);
590 
591 	/* setup our pseudo HTC control endpoint connection */
592 	memset(&conn_req, 0, sizeof(conn_req));
593 	memset(&conn_resp, 0, sizeof(conn_resp));
594 	conn_req.ep_ops.ep_tx_complete = ath10k_htc_control_tx_complete;
595 	conn_req.ep_ops.ep_rx_complete = ath10k_htc_control_rx_complete;
596 	conn_req.max_send_queue_depth = ATH10K_NUM_CONTROL_TX_BUFFERS;
597 	conn_req.service_id = ATH10K_HTC_SVC_ID_RSVD_CTRL;
598 
599 	/* connect fake service */
600 	status = ath10k_htc_connect_service(htc, &conn_req, &conn_resp);
601 	if (status) {
602 		ath10k_err("could not connect to htc service (%d)\n", status);
603 		goto err_target;
604 	}
605 
606 	return 0;
607 err_target:
608 	ath10k_hif_stop(htc->ar);
609 err_start:
610 	return status;
611 }
612 
613 int ath10k_htc_connect_service(struct ath10k_htc *htc,
614 			       struct ath10k_htc_svc_conn_req *conn_req,
615 			       struct ath10k_htc_svc_conn_resp *conn_resp)
616 {
617 	struct ath10k_htc_msg *msg;
618 	struct ath10k_htc_conn_svc *req_msg;
619 	struct ath10k_htc_conn_svc_response resp_msg_dummy;
620 	struct ath10k_htc_conn_svc_response *resp_msg = &resp_msg_dummy;
621 	enum ath10k_htc_ep_id assigned_eid = ATH10K_HTC_EP_COUNT;
622 	struct ath10k_htc_ep *ep;
623 	struct sk_buff *skb;
624 	unsigned int max_msg_size = 0;
625 	int length, status;
626 	bool disable_credit_flow_ctrl = false;
627 	u16 message_id, service_id, flags = 0;
628 	u8 tx_alloc = 0;
629 
630 	/* special case for HTC pseudo control service */
631 	if (conn_req->service_id == ATH10K_HTC_SVC_ID_RSVD_CTRL) {
632 		disable_credit_flow_ctrl = true;
633 		assigned_eid = ATH10K_HTC_EP_0;
634 		max_msg_size = ATH10K_HTC_MAX_CTRL_MSG_LEN;
635 		memset(&resp_msg_dummy, 0, sizeof(resp_msg_dummy));
636 		goto setup;
637 	}
638 
639 	tx_alloc = ath10k_htc_get_credit_allocation(htc,
640 						    conn_req->service_id);
641 	if (!tx_alloc)
642 		ath10k_dbg(ATH10K_DBG_BOOT,
643 			   "boot htc service %s does not allocate target credits\n",
644 			   htc_service_name(conn_req->service_id));
645 
646 	skb = ath10k_htc_build_tx_ctrl_skb(htc->ar);
647 	if (!skb) {
648 		ath10k_err("Failed to allocate HTC packet\n");
649 		return -ENOMEM;
650 	}
651 
652 	length = sizeof(msg->hdr) + sizeof(msg->connect_service);
653 	skb_put(skb, length);
654 	memset(skb->data, 0, length);
655 
656 	msg = (struct ath10k_htc_msg *)skb->data;
657 	msg->hdr.message_id =
658 		__cpu_to_le16(ATH10K_HTC_MSG_CONNECT_SERVICE_ID);
659 
660 	flags |= SM(tx_alloc, ATH10K_HTC_CONN_FLAGS_RECV_ALLOC);
661 
662 	/* Only enable credit flow control for WMI ctrl service */
663 	if (conn_req->service_id != ATH10K_HTC_SVC_ID_WMI_CONTROL) {
664 		flags |= ATH10K_HTC_CONN_FLAGS_DISABLE_CREDIT_FLOW_CTRL;
665 		disable_credit_flow_ctrl = true;
666 	}
667 
668 	req_msg = &msg->connect_service;
669 	req_msg->flags = __cpu_to_le16(flags);
670 	req_msg->service_id = __cpu_to_le16(conn_req->service_id);
671 
672 	reinit_completion(&htc->ctl_resp);
673 
674 	status = ath10k_htc_send(htc, ATH10K_HTC_EP_0, skb);
675 	if (status) {
676 		kfree_skb(skb);
677 		return status;
678 	}
679 
680 	/* wait for response */
681 	status = wait_for_completion_timeout(&htc->ctl_resp,
682 					     ATH10K_HTC_CONN_SVC_TIMEOUT_HZ);
683 	if (status <= 0) {
684 		if (status == 0)
685 			status = -ETIMEDOUT;
686 		ath10k_err("Service connect timeout: %d\n", status);
687 		return status;
688 	}
689 
690 	/* we controlled the buffer creation, it's aligned */
691 	msg = (struct ath10k_htc_msg *)htc->control_resp_buffer;
692 	resp_msg = &msg->connect_service_response;
693 	message_id = __le16_to_cpu(msg->hdr.message_id);
694 	service_id = __le16_to_cpu(resp_msg->service_id);
695 
696 	if ((message_id != ATH10K_HTC_MSG_CONNECT_SERVICE_RESP_ID) ||
697 	    (htc->control_resp_len < sizeof(msg->hdr) +
698 	     sizeof(msg->connect_service_response))) {
699 		ath10k_err("Invalid resp message ID 0x%x", message_id);
700 		return -EPROTO;
701 	}
702 
703 	ath10k_dbg(ATH10K_DBG_HTC,
704 		   "HTC Service %s connect response: status: 0x%x, assigned ep: 0x%x\n",
705 		   htc_service_name(service_id),
706 		   resp_msg->status, resp_msg->eid);
707 
708 	conn_resp->connect_resp_code = resp_msg->status;
709 
710 	/* check response status */
711 	if (resp_msg->status != ATH10K_HTC_CONN_SVC_STATUS_SUCCESS) {
712 		ath10k_err("HTC Service %s connect request failed: 0x%x)\n",
713 			   htc_service_name(service_id),
714 			   resp_msg->status);
715 		return -EPROTO;
716 	}
717 
718 	assigned_eid = (enum ath10k_htc_ep_id)resp_msg->eid;
719 	max_msg_size = __le16_to_cpu(resp_msg->max_msg_size);
720 
721 setup:
722 
723 	if (assigned_eid >= ATH10K_HTC_EP_COUNT)
724 		return -EPROTO;
725 
726 	if (max_msg_size == 0)
727 		return -EPROTO;
728 
729 	ep = &htc->endpoint[assigned_eid];
730 	ep->eid = assigned_eid;
731 
732 	if (ep->service_id != ATH10K_HTC_SVC_ID_UNUSED)
733 		return -EPROTO;
734 
735 	/* return assigned endpoint to caller */
736 	conn_resp->eid = assigned_eid;
737 	conn_resp->max_msg_len = __le16_to_cpu(resp_msg->max_msg_size);
738 
739 	/* setup the endpoint */
740 	ep->service_id = conn_req->service_id;
741 	ep->max_tx_queue_depth = conn_req->max_send_queue_depth;
742 	ep->max_ep_message_len = __le16_to_cpu(resp_msg->max_msg_size);
743 	ep->tx_credits = tx_alloc;
744 	ep->tx_credit_size = htc->target_credit_size;
745 	ep->tx_credits_per_max_message = ep->max_ep_message_len /
746 					 htc->target_credit_size;
747 
748 	if (ep->max_ep_message_len % htc->target_credit_size)
749 		ep->tx_credits_per_max_message++;
750 
751 	/* copy all the callbacks */
752 	ep->ep_ops = conn_req->ep_ops;
753 
754 	status = ath10k_hif_map_service_to_pipe(htc->ar,
755 						ep->service_id,
756 						&ep->ul_pipe_id,
757 						&ep->dl_pipe_id,
758 						&ep->ul_is_polled,
759 						&ep->dl_is_polled);
760 	if (status)
761 		return status;
762 
763 	ath10k_dbg(ATH10K_DBG_BOOT,
764 		   "boot htc service '%s' ul pipe %d dl pipe %d eid %d ready\n",
765 		   htc_service_name(ep->service_id), ep->ul_pipe_id,
766 		   ep->dl_pipe_id, ep->eid);
767 
768 	ath10k_dbg(ATH10K_DBG_BOOT,
769 		   "boot htc ep %d ul polled %d dl polled %d\n",
770 		   ep->eid, ep->ul_is_polled, ep->dl_is_polled);
771 
772 	if (disable_credit_flow_ctrl && ep->tx_credit_flow_enabled) {
773 		ep->tx_credit_flow_enabled = false;
774 		ath10k_dbg(ATH10K_DBG_BOOT,
775 			   "boot htc service '%s' eid %d TX flow control disabled\n",
776 			   htc_service_name(ep->service_id), assigned_eid);
777 	}
778 
779 	return status;
780 }
781 
782 struct sk_buff *ath10k_htc_alloc_skb(int size)
783 {
784 	struct sk_buff *skb;
785 
786 	skb = dev_alloc_skb(size + sizeof(struct ath10k_htc_hdr));
787 	if (!skb) {
788 		ath10k_warn("could not allocate HTC tx skb\n");
789 		return NULL;
790 	}
791 
792 	skb_reserve(skb, sizeof(struct ath10k_htc_hdr));
793 
794 	/* FW/HTC requires 4-byte aligned streams */
795 	if (!IS_ALIGNED((unsigned long)skb->data, 4))
796 		ath10k_warn("Unaligned HTC tx skb\n");
797 
798 	return skb;
799 }
800 
801 int ath10k_htc_start(struct ath10k_htc *htc)
802 {
803 	struct sk_buff *skb;
804 	int status = 0;
805 	struct ath10k_htc_msg *msg;
806 
807 	skb = ath10k_htc_build_tx_ctrl_skb(htc->ar);
808 	if (!skb)
809 		return -ENOMEM;
810 
811 	skb_put(skb, sizeof(msg->hdr) + sizeof(msg->setup_complete_ext));
812 	memset(skb->data, 0, skb->len);
813 
814 	msg = (struct ath10k_htc_msg *)skb->data;
815 	msg->hdr.message_id =
816 		__cpu_to_le16(ATH10K_HTC_MSG_SETUP_COMPLETE_EX_ID);
817 
818 	ath10k_dbg(ATH10K_DBG_HTC, "HTC is using TX credit flow control\n");
819 
820 	status = ath10k_htc_send(htc, ATH10K_HTC_EP_0, skb);
821 	if (status) {
822 		kfree_skb(skb);
823 		return status;
824 	}
825 
826 	return 0;
827 }
828 
829 /*
830  * stop HTC communications, i.e. stop interrupt reception, and flush all
831  * queued buffers
832  */
833 void ath10k_htc_stop(struct ath10k_htc *htc)
834 {
835 	spin_lock_bh(&htc->tx_lock);
836 	htc->stopped = true;
837 	spin_unlock_bh(&htc->tx_lock);
838 
839 	ath10k_hif_stop(htc->ar);
840 }
841 
842 /* registered target arrival callback from the HIF layer */
843 int ath10k_htc_init(struct ath10k *ar)
844 {
845 	struct ath10k_hif_cb htc_callbacks;
846 	struct ath10k_htc_ep *ep = NULL;
847 	struct ath10k_htc *htc = &ar->htc;
848 
849 	spin_lock_init(&htc->tx_lock);
850 
851 	htc->stopped = false;
852 	ath10k_htc_reset_endpoint_states(htc);
853 
854 	/* setup HIF layer callbacks */
855 	htc_callbacks.rx_completion = ath10k_htc_rx_completion_handler;
856 	htc_callbacks.tx_completion = ath10k_htc_tx_completion_handler;
857 	htc->ar = ar;
858 
859 	/* Get HIF default pipe for HTC message exchange */
860 	ep = &htc->endpoint[ATH10K_HTC_EP_0];
861 
862 	ath10k_hif_set_callbacks(ar, &htc_callbacks);
863 	ath10k_hif_get_default_pipe(ar, &ep->ul_pipe_id, &ep->dl_pipe_id);
864 
865 	init_completion(&htc->ctl_resp);
866 
867 	return 0;
868 }
869