xref: /linux/drivers/net/wireless/ath/ath12k/htc.c (revision 1fd1dc41724319406b0aff221a352a400b0ddfc5)
1 // SPDX-License-Identifier: BSD-3-Clause-Clear
2 /*
3  * Copyright (c) 2018-2021 The Linux Foundation. All rights reserved.
4  * Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries.
5  */
6 #include <linux/skbuff.h>
7 #include <linux/ctype.h>
8 
9 #include "debug.h"
10 #include "hif.h"
11 
12 struct sk_buff *ath12k_htc_alloc_skb(struct ath12k_base *ab, int size)
13 {
14 	struct sk_buff *skb;
15 
16 	skb = dev_alloc_skb(size + sizeof(struct ath12k_htc_hdr));
17 	if (!skb)
18 		return NULL;
19 
20 	skb_reserve(skb, sizeof(struct ath12k_htc_hdr));
21 
22 	/* FW/HTC requires 4-byte aligned streams */
23 	if (!IS_ALIGNED((unsigned long)skb->data, 4))
24 		ath12k_warn(ab, "Unaligned HTC tx skb\n");
25 
26 	return skb;
27 }
28 
29 static void ath12k_htc_control_tx_complete(struct ath12k_base *ab,
30 					   struct sk_buff *skb)
31 {
32 	kfree_skb(skb);
33 }
34 
35 static struct sk_buff *ath12k_htc_build_tx_ctrl_skb(void)
36 {
37 	struct sk_buff *skb;
38 	struct ath12k_skb_cb *skb_cb;
39 
40 	skb = dev_alloc_skb(ATH12K_HTC_CONTROL_BUFFER_SIZE);
41 	if (!skb)
42 		return NULL;
43 
44 	skb_reserve(skb, sizeof(struct ath12k_htc_hdr));
45 	WARN_ON_ONCE(!IS_ALIGNED((unsigned long)skb->data, 4));
46 
47 	skb_cb = ATH12K_SKB_CB(skb);
48 	memset(skb_cb, 0, sizeof(*skb_cb));
49 
50 	return skb;
51 }
52 
53 static void ath12k_htc_prepare_tx_skb(struct ath12k_htc_ep *ep,
54 				      struct sk_buff *skb)
55 {
56 	struct ath12k_htc_hdr *hdr;
57 
58 	hdr = (struct ath12k_htc_hdr *)skb->data;
59 
60 	memset(hdr, 0, sizeof(*hdr));
61 	hdr->htc_info = le32_encode_bits(ep->eid, HTC_HDR_ENDPOINTID) |
62 			le32_encode_bits((skb->len - sizeof(*hdr)),
63 					 HTC_HDR_PAYLOADLEN);
64 
65 	if (ep->tx_credit_flow_enabled)
66 		hdr->htc_info |= le32_encode_bits(ATH12K_HTC_FLAG_NEED_CREDIT_UPDATE,
67 						  HTC_HDR_FLAGS);
68 
69 	spin_lock_bh(&ep->htc->tx_lock);
70 	hdr->ctrl_info = le32_encode_bits(ep->seq_no++, HTC_HDR_CONTROLBYTES1);
71 	spin_unlock_bh(&ep->htc->tx_lock);
72 }
73 
74 int ath12k_htc_send(struct ath12k_htc *htc,
75 		    enum ath12k_htc_ep_id eid,
76 		    struct sk_buff *skb)
77 {
78 	struct ath12k_htc_ep *ep = &htc->endpoint[eid];
79 	struct ath12k_skb_cb *skb_cb = ATH12K_SKB_CB(skb);
80 	struct device *dev = htc->ab->dev;
81 	struct ath12k_base *ab = htc->ab;
82 	int credits = 0;
83 	int ret;
84 
85 	if (eid >= ATH12K_HTC_EP_COUNT) {
86 		ath12k_warn(ab, "Invalid endpoint id: %d\n", eid);
87 		return -ENOENT;
88 	}
89 
90 	skb_push(skb, sizeof(struct ath12k_htc_hdr));
91 
92 	if (ep->tx_credit_flow_enabled) {
93 		credits = DIV_ROUND_UP(skb->len, htc->target_credit_size);
94 		spin_lock_bh(&htc->tx_lock);
95 		if (ep->tx_credits < credits) {
96 			ath12k_dbg(ab, ATH12K_DBG_HTC,
97 				   "htc insufficient credits ep %d required %d available %d\n",
98 				   eid, credits, ep->tx_credits);
99 			spin_unlock_bh(&htc->tx_lock);
100 			ret = -EAGAIN;
101 			goto err_pull;
102 		}
103 		ep->tx_credits -= credits;
104 		ath12k_dbg(ab, ATH12K_DBG_HTC,
105 			   "htc ep %d consumed %d credits (total %d)\n",
106 			   eid, credits, ep->tx_credits);
107 		spin_unlock_bh(&htc->tx_lock);
108 	}
109 
110 	ath12k_htc_prepare_tx_skb(ep, skb);
111 
112 	skb_cb->paddr = dma_map_single(dev, skb->data, skb->len, DMA_TO_DEVICE);
113 	ret = dma_mapping_error(dev, skb_cb->paddr);
114 	if (ret) {
115 		ret = -EIO;
116 		goto err_credits;
117 	}
118 
119 	ret = ath12k_ce_send(htc->ab, skb, ep->ul_pipe_id, ep->eid);
120 	if (ret)
121 		goto err_unmap;
122 
123 	return 0;
124 
125 err_unmap:
126 	dma_unmap_single(dev, skb_cb->paddr, skb->len, DMA_TO_DEVICE);
127 err_credits:
128 	if (ep->tx_credit_flow_enabled) {
129 		spin_lock_bh(&htc->tx_lock);
130 		ep->tx_credits += credits;
131 		ath12k_dbg(ab, ATH12K_DBG_HTC,
132 			   "htc ep %d reverted %d credits back (total %d)\n",
133 			   eid, credits, ep->tx_credits);
134 		spin_unlock_bh(&htc->tx_lock);
135 
136 		if (ep->ep_ops.ep_tx_credits)
137 			ep->ep_ops.ep_tx_credits(htc->ab);
138 	}
139 err_pull:
140 	skb_pull(skb, sizeof(struct ath12k_htc_hdr));
141 	return ret;
142 }
143 
144 static void
145 ath12k_htc_process_credit_report(struct ath12k_htc *htc,
146 				 const struct ath12k_htc_credit_report *report,
147 				 int len,
148 				 enum ath12k_htc_ep_id eid)
149 {
150 	struct ath12k_base *ab = htc->ab;
151 	struct ath12k_htc_ep *ep;
152 	int i, n_reports;
153 
154 	if (len % sizeof(*report))
155 		ath12k_warn(ab, "Uneven credit report len %d", len);
156 
157 	n_reports = len / sizeof(*report);
158 
159 	spin_lock_bh(&htc->tx_lock);
160 	for (i = 0; i < n_reports; i++, report++) {
161 		if (report->eid >= ATH12K_HTC_EP_COUNT)
162 			break;
163 
164 		ep = &htc->endpoint[report->eid];
165 		ep->tx_credits += report->credits;
166 
167 		ath12k_dbg(ab, ATH12K_DBG_HTC, "htc ep %d got %d credits (total %d)\n",
168 			   report->eid, report->credits, ep->tx_credits);
169 
170 		if (ep->ep_ops.ep_tx_credits) {
171 			spin_unlock_bh(&htc->tx_lock);
172 			ep->ep_ops.ep_tx_credits(htc->ab);
173 			spin_lock_bh(&htc->tx_lock);
174 		}
175 	}
176 	spin_unlock_bh(&htc->tx_lock);
177 }
178 
179 static int ath12k_htc_process_trailer(struct ath12k_htc *htc,
180 				      u8 *buffer,
181 				      int length,
182 				      enum ath12k_htc_ep_id src_eid)
183 {
184 	struct ath12k_base *ab = htc->ab;
185 	int status = 0;
186 	struct ath12k_htc_record *record;
187 	size_t len;
188 
189 	while (length > 0) {
190 		record = (struct ath12k_htc_record *)buffer;
191 
192 		if (length < sizeof(record->hdr)) {
193 			status = -EINVAL;
194 			break;
195 		}
196 
197 		if (record->hdr.len > length) {
198 			/* no room left in buffer for record */
199 			ath12k_warn(ab, "Invalid record length: %d\n",
200 				    record->hdr.len);
201 			status = -EINVAL;
202 			break;
203 		}
204 
205 		switch (record->hdr.id) {
206 		case ATH12K_HTC_RECORD_CREDITS:
207 			len = sizeof(struct ath12k_htc_credit_report);
208 			if (record->hdr.len < len) {
209 				ath12k_warn(ab, "Credit report too long\n");
210 				status = -EINVAL;
211 				break;
212 			}
213 			ath12k_htc_process_credit_report(htc,
214 							 record->credit_report,
215 							 record->hdr.len,
216 							 src_eid);
217 			break;
218 		default:
219 			ath12k_warn(ab, "Unhandled record: id:%d length:%d\n",
220 				    record->hdr.id, record->hdr.len);
221 			break;
222 		}
223 
224 		if (status)
225 			break;
226 
227 		/* multiple records may be present in a trailer */
228 		buffer += sizeof(record->hdr) + record->hdr.len;
229 		length -= sizeof(record->hdr) + record->hdr.len;
230 	}
231 
232 	return status;
233 }
234 
235 static void ath12k_htc_suspend_complete(struct ath12k_base *ab, bool ack)
236 {
237 	ath12k_dbg(ab, ATH12K_DBG_BOOT, "boot suspend complete %d\n", ack);
238 
239 	if (ack)
240 		set_bit(ATH12K_FLAG_HTC_SUSPEND_COMPLETE, &ab->dev_flags);
241 	else
242 		clear_bit(ATH12K_FLAG_HTC_SUSPEND_COMPLETE, &ab->dev_flags);
243 
244 	complete(&ab->htc_suspend);
245 }
246 
247 static void ath12k_htc_wakeup_from_suspend(struct ath12k_base *ab)
248 {
249 	ath12k_dbg(ab, ATH12K_DBG_BOOT, "boot wakeup from suspend is received\n");
250 }
251 
252 void ath12k_htc_rx_completion_handler(struct ath12k_base *ab,
253 				      struct sk_buff *skb)
254 {
255 	int status = 0;
256 	struct ath12k_htc *htc = &ab->htc;
257 	struct ath12k_htc_hdr *hdr;
258 	struct ath12k_htc_ep *ep;
259 	u16 payload_len;
260 	u32 trailer_len = 0;
261 	size_t min_len;
262 	u8 eid;
263 	bool trailer_present;
264 
265 	hdr = (struct ath12k_htc_hdr *)skb->data;
266 	skb_pull(skb, sizeof(*hdr));
267 
268 	eid = le32_get_bits(hdr->htc_info, HTC_HDR_ENDPOINTID);
269 
270 	if (eid >= ATH12K_HTC_EP_COUNT) {
271 		ath12k_warn(ab, "HTC Rx: invalid eid %d\n", eid);
272 		goto out;
273 	}
274 
275 	ep = &htc->endpoint[eid];
276 
277 	payload_len = le32_get_bits(hdr->htc_info, HTC_HDR_PAYLOADLEN);
278 
279 	if (payload_len + sizeof(*hdr) > ATH12K_HTC_MAX_LEN) {
280 		ath12k_warn(ab, "HTC rx frame too long, len: %zu\n",
281 			    payload_len + sizeof(*hdr));
282 		goto out;
283 	}
284 
285 	if (skb->len < payload_len) {
286 		ath12k_warn(ab, "HTC Rx: insufficient length, got %d, expected %d\n",
287 			    skb->len, payload_len);
288 		goto out;
289 	}
290 
291 	/* get flags to check for trailer */
292 	trailer_present = le32_get_bits(hdr->htc_info, HTC_HDR_FLAGS) &
293 			  ATH12K_HTC_FLAG_TRAILER_PRESENT;
294 
295 	if (trailer_present) {
296 		u8 *trailer;
297 
298 		trailer_len = le32_get_bits(hdr->ctrl_info,
299 					    HTC_HDR_CONTROLBYTES0);
300 		min_len = sizeof(struct ath12k_htc_record_hdr);
301 
302 		if ((trailer_len < min_len) ||
303 		    (trailer_len > payload_len)) {
304 			ath12k_warn(ab, "Invalid trailer length: %d\n",
305 				    trailer_len);
306 			goto out;
307 		}
308 
309 		trailer = (u8 *)hdr;
310 		trailer += sizeof(*hdr);
311 		trailer += payload_len;
312 		trailer -= trailer_len;
313 		status = ath12k_htc_process_trailer(htc, trailer,
314 						    trailer_len, eid);
315 		if (status)
316 			goto out;
317 
318 		skb_trim(skb, skb->len - trailer_len);
319 	}
320 
321 	if (trailer_len >= payload_len)
322 		/* zero length packet with trailer data, just drop these */
323 		goto out;
324 
325 	if (eid == ATH12K_HTC_EP_0) {
326 		struct ath12k_htc_msg *msg = (struct ath12k_htc_msg *)skb->data;
327 
328 		switch (le32_get_bits(msg->msg_svc_id, HTC_MSG_MESSAGEID)) {
329 		case ATH12K_HTC_MSG_READY_ID:
330 		case ATH12K_HTC_MSG_CONNECT_SERVICE_RESP_ID:
331 			/* handle HTC control message */
332 			if (completion_done(&htc->ctl_resp)) {
333 				/* this is a fatal error, target should not be
334 				 * sending unsolicited messages on the ep 0
335 				 */
336 				ath12k_warn(ab, "HTC rx ctrl still processing\n");
337 				complete(&htc->ctl_resp);
338 				goto out;
339 			}
340 
341 			htc->control_resp_len =
342 				min_t(int, skb->len,
343 				      ATH12K_HTC_MAX_CTRL_MSG_LEN);
344 
345 			memcpy(htc->control_resp_buffer, skb->data,
346 			       htc->control_resp_len);
347 
348 			complete(&htc->ctl_resp);
349 			break;
350 		case ATH12K_HTC_MSG_SEND_SUSPEND_COMPLETE:
351 			ath12k_htc_suspend_complete(ab, true);
352 			break;
353 		case ATH12K_HTC_MSG_NACK_SUSPEND:
354 			ath12k_htc_suspend_complete(ab, false);
355 			break;
356 		case ATH12K_HTC_MSG_WAKEUP_FROM_SUSPEND_ID:
357 			ath12k_htc_wakeup_from_suspend(ab);
358 			break;
359 		default:
360 			ath12k_warn(ab, "ignoring unsolicited htc ep0 event %u\n",
361 				    le32_get_bits(msg->msg_svc_id, HTC_MSG_MESSAGEID));
362 			break;
363 		}
364 		goto out;
365 	}
366 
367 	ath12k_dbg(ab, ATH12K_DBG_HTC, "htc rx completion ep %d skb %p\n",
368 		   eid, skb);
369 	ep->ep_ops.ep_rx_complete(ab, skb);
370 
371 	/* poll tx completion for interrupt disabled CE's */
372 	ath12k_ce_poll_send_completed(ab, ep->ul_pipe_id);
373 
374 	/* skb is now owned by the rx completion handler */
375 	skb = NULL;
376 out:
377 	kfree_skb(skb);
378 }
379 EXPORT_SYMBOL(ath12k_htc_rx_completion_handler);
380 
381 static void ath12k_htc_control_rx_complete(struct ath12k_base *ab,
382 					   struct sk_buff *skb)
383 {
384 	/* This is unexpected. FW is not supposed to send regular rx on this
385 	 * endpoint.
386 	 */
387 	ath12k_warn(ab, "unexpected htc rx\n");
388 	kfree_skb(skb);
389 }
390 
391 static const char *htc_service_name(enum ath12k_htc_svc_id id)
392 {
393 	switch (id) {
394 	case ATH12K_HTC_SVC_ID_RESERVED:
395 		return "Reserved";
396 	case ATH12K_HTC_SVC_ID_RSVD_CTRL:
397 		return "Control";
398 	case ATH12K_HTC_SVC_ID_WMI_CONTROL:
399 		return "WMI";
400 	case ATH12K_HTC_SVC_ID_WMI_DATA_BE:
401 		return "DATA BE";
402 	case ATH12K_HTC_SVC_ID_WMI_DATA_BK:
403 		return "DATA BK";
404 	case ATH12K_HTC_SVC_ID_WMI_DATA_VI:
405 		return "DATA VI";
406 	case ATH12K_HTC_SVC_ID_WMI_DATA_VO:
407 		return "DATA VO";
408 	case ATH12K_HTC_SVC_ID_WMI_CONTROL_MAC1:
409 		return "WMI MAC1";
410 	case ATH12K_HTC_SVC_ID_WMI_CONTROL_MAC2:
411 		return "WMI MAC2";
412 	case ATH12K_HTC_SVC_ID_NMI_CONTROL:
413 		return "NMI Control";
414 	case ATH12K_HTC_SVC_ID_NMI_DATA:
415 		return "NMI Data";
416 	case ATH12K_HTC_SVC_ID_HTT_DATA_MSG:
417 		return "HTT Data";
418 	case ATH12K_HTC_SVC_ID_TEST_RAW_STREAMS:
419 		return "RAW";
420 	case ATH12K_HTC_SVC_ID_IPA_TX:
421 		return "IPA TX";
422 	case ATH12K_HTC_SVC_ID_PKT_LOG:
423 		return "PKT LOG";
424 	case ATH12K_HTC_SVC_ID_WMI_CONTROL_DIAG:
425 		return "WMI DIAG";
426 	}
427 
428 	return "Unknown";
429 }
430 
431 static void ath12k_htc_reset_endpoint_states(struct ath12k_htc *htc)
432 {
433 	struct ath12k_htc_ep *ep;
434 	int i;
435 
436 	for (i = ATH12K_HTC_EP_0; i < ATH12K_HTC_EP_COUNT; i++) {
437 		ep = &htc->endpoint[i];
438 		ep->service_id = ATH12K_HTC_SVC_ID_UNUSED;
439 		ep->max_ep_message_len = 0;
440 		ep->max_tx_queue_depth = 0;
441 		ep->eid = i;
442 		ep->htc = htc;
443 		ep->tx_credit_flow_enabled = true;
444 	}
445 }
446 
447 static u8 ath12k_htc_get_credit_allocation(struct ath12k_htc *htc,
448 					   u16 service_id)
449 {
450 	struct ath12k_htc_svc_tx_credits *serv_entry;
451 	u8 i, allocation = 0;
452 
453 	serv_entry = htc->service_alloc_table;
454 
455 	for (i = 0; i < ATH12K_HTC_MAX_SERVICE_ALLOC_ENTRIES; i++) {
456 		if (serv_entry[i].service_id == service_id) {
457 			allocation = serv_entry[i].credit_allocation;
458 			break;
459 		}
460 	}
461 
462 	return allocation;
463 }
464 
465 static int ath12k_htc_setup_target_buffer_assignments(struct ath12k_htc *htc)
466 {
467 	struct ath12k_htc_svc_tx_credits *serv_entry;
468 	static const u32 svc_id[] = {
469 					ATH12K_HTC_SVC_ID_WMI_CONTROL,
470 					ATH12K_HTC_SVC_ID_WMI_CONTROL_MAC1,
471 					ATH12K_HTC_SVC_ID_WMI_CONTROL_MAC2,
472 				};
473 	int i, credits;
474 
475 	credits = htc->total_transmit_credits;
476 	serv_entry = htc->service_alloc_table;
477 
478 	if ((htc->wmi_ep_count == 0) ||
479 	    (htc->wmi_ep_count > ARRAY_SIZE(svc_id)))
480 		return -EINVAL;
481 
482 	/* Divide credits among number of endpoints for WMI */
483 	credits = credits / htc->wmi_ep_count;
484 	for (i = 0; i < htc->wmi_ep_count; i++) {
485 		serv_entry[i].service_id = svc_id[i];
486 		serv_entry[i].credit_allocation = credits;
487 	}
488 
489 	return 0;
490 }
491 
492 int ath12k_htc_wait_target(struct ath12k_htc *htc)
493 {
494 	int i, status = 0;
495 	struct ath12k_base *ab = htc->ab;
496 	unsigned long time_left;
497 	struct ath12k_htc_ready *ready;
498 	u16 message_id;
499 	u16 credit_count;
500 	u16 credit_size;
501 
502 	time_left = wait_for_completion_timeout(&htc->ctl_resp,
503 						ATH12K_HTC_WAIT_TIMEOUT_HZ);
504 	if (!time_left) {
505 		ath12k_warn(ab, "failed to receive control response completion, polling..\n");
506 
507 		for (i = 0; i < ab->hw_params->ce_count; i++)
508 			ath12k_ce_per_engine_service(htc->ab, i);
509 
510 		time_left =
511 			wait_for_completion_timeout(&htc->ctl_resp,
512 						    ATH12K_HTC_WAIT_TIMEOUT_HZ);
513 
514 		if (!time_left)
515 			status = -ETIMEDOUT;
516 	}
517 
518 	if (status < 0) {
519 		ath12k_warn(ab, "ctl_resp never came in (%d)\n", status);
520 		return status;
521 	}
522 
523 	if (htc->control_resp_len < sizeof(*ready)) {
524 		ath12k_warn(ab, "Invalid HTC ready msg len:%d\n",
525 			    htc->control_resp_len);
526 		return -ECOMM;
527 	}
528 
529 	ready = (struct ath12k_htc_ready *)htc->control_resp_buffer;
530 	message_id = le32_get_bits(ready->id_credit_count, HTC_MSG_MESSAGEID);
531 	credit_count = le32_get_bits(ready->id_credit_count,
532 				     HTC_READY_MSG_CREDITCOUNT);
533 	credit_size = le32_get_bits(ready->size_ep, HTC_READY_MSG_CREDITSIZE);
534 
535 	if (message_id != ATH12K_HTC_MSG_READY_ID) {
536 		ath12k_warn(ab, "Invalid HTC ready msg: 0x%x\n", message_id);
537 		return -ECOMM;
538 	}
539 
540 	htc->total_transmit_credits = credit_count;
541 	htc->target_credit_size = credit_size;
542 
543 	ath12k_dbg(ab, ATH12K_DBG_HTC,
544 		   "Target ready! transmit resources: %d size:%d\n",
545 		   htc->total_transmit_credits, htc->target_credit_size);
546 
547 	if ((htc->total_transmit_credits == 0) ||
548 	    (htc->target_credit_size == 0)) {
549 		ath12k_warn(ab, "Invalid credit size received\n");
550 		return -ECOMM;
551 	}
552 
553 	ath12k_htc_setup_target_buffer_assignments(htc);
554 
555 	return 0;
556 }
557 
558 int ath12k_htc_connect_service(struct ath12k_htc *htc,
559 			       struct ath12k_htc_svc_conn_req *conn_req,
560 			       struct ath12k_htc_svc_conn_resp *conn_resp)
561 {
562 	struct ath12k_base *ab = htc->ab;
563 	struct ath12k_htc_conn_svc *req_msg;
564 	struct ath12k_htc_conn_svc_resp resp_msg_dummy;
565 	struct ath12k_htc_conn_svc_resp *resp_msg = &resp_msg_dummy;
566 	enum ath12k_htc_ep_id assigned_eid = ATH12K_HTC_EP_COUNT;
567 	struct ath12k_htc_ep *ep;
568 	struct sk_buff *skb;
569 	unsigned int max_msg_size = 0;
570 	int length, status;
571 	unsigned long time_left;
572 	bool disable_credit_flow_ctrl = false;
573 	u16 message_id, service_id, flags = 0;
574 	u8 tx_alloc = 0;
575 
576 	/* special case for HTC pseudo control service */
577 	if (conn_req->service_id == ATH12K_HTC_SVC_ID_RSVD_CTRL) {
578 		disable_credit_flow_ctrl = true;
579 		assigned_eid = ATH12K_HTC_EP_0;
580 		max_msg_size = ATH12K_HTC_MAX_CTRL_MSG_LEN;
581 		memset(&resp_msg_dummy, 0, sizeof(resp_msg_dummy));
582 		goto setup;
583 	}
584 
585 	tx_alloc = ath12k_htc_get_credit_allocation(htc,
586 						    conn_req->service_id);
587 	if (!tx_alloc)
588 		ath12k_dbg(ab, ATH12K_DBG_BOOT,
589 			   "boot htc service %s does not allocate target credits\n",
590 			   htc_service_name(conn_req->service_id));
591 
592 	skb = ath12k_htc_build_tx_ctrl_skb();
593 	if (!skb) {
594 		ath12k_warn(ab, "Failed to allocate HTC packet\n");
595 		return -ENOMEM;
596 	}
597 
598 	length = sizeof(*req_msg);
599 	skb_put(skb, length);
600 	memset(skb->data, 0, length);
601 
602 	req_msg = (struct ath12k_htc_conn_svc *)skb->data;
603 	req_msg->msg_svc_id = le32_encode_bits(ATH12K_HTC_MSG_CONNECT_SERVICE_ID,
604 					       HTC_MSG_MESSAGEID);
605 
606 	flags |= u32_encode_bits(tx_alloc, ATH12K_HTC_CONN_FLAGS_RECV_ALLOC);
607 
608 	/* Only enable credit flow control for WMI ctrl service */
609 	if (!(conn_req->service_id == ATH12K_HTC_SVC_ID_WMI_CONTROL ||
610 	      conn_req->service_id == ATH12K_HTC_SVC_ID_WMI_CONTROL_MAC1 ||
611 	      conn_req->service_id == ATH12K_HTC_SVC_ID_WMI_CONTROL_MAC2)) {
612 		flags |= ATH12K_HTC_CONN_FLAGS_DISABLE_CREDIT_FLOW_CTRL;
613 		disable_credit_flow_ctrl = true;
614 	}
615 
616 	req_msg->flags_len = le32_encode_bits(flags, HTC_SVC_MSG_CONNECTIONFLAGS);
617 	req_msg->msg_svc_id |= le32_encode_bits(conn_req->service_id,
618 						HTC_SVC_MSG_SERVICE_ID);
619 
620 	reinit_completion(&htc->ctl_resp);
621 
622 	status = ath12k_htc_send(htc, ATH12K_HTC_EP_0, skb);
623 	if (status) {
624 		kfree_skb(skb);
625 		return status;
626 	}
627 
628 	/* wait for response */
629 	time_left = wait_for_completion_timeout(&htc->ctl_resp,
630 						ATH12K_HTC_CONN_SVC_TIMEOUT_HZ);
631 	if (!time_left) {
632 		ath12k_err(ab, "Service connect timeout\n");
633 		return -ETIMEDOUT;
634 	}
635 
636 	/* we controlled the buffer creation, it's aligned */
637 	resp_msg = (struct ath12k_htc_conn_svc_resp *)htc->control_resp_buffer;
638 	message_id = le32_get_bits(resp_msg->msg_svc_id, HTC_MSG_MESSAGEID);
639 	service_id = le32_get_bits(resp_msg->msg_svc_id,
640 				   HTC_SVC_RESP_MSG_SERVICEID);
641 
642 	if ((message_id != ATH12K_HTC_MSG_CONNECT_SERVICE_RESP_ID) ||
643 	    (htc->control_resp_len < sizeof(*resp_msg))) {
644 		ath12k_err(ab, "Invalid resp message ID 0x%x", message_id);
645 		return -EPROTO;
646 	}
647 
648 	ath12k_dbg(ab, ATH12K_DBG_HTC,
649 		   "HTC Service %s connect response: status: %u, assigned ep: %u\n",
650 		   htc_service_name(service_id),
651 		   le32_get_bits(resp_msg->flags_len, HTC_SVC_RESP_MSG_STATUS),
652 		   le32_get_bits(resp_msg->flags_len, HTC_SVC_RESP_MSG_ENDPOINTID));
653 
654 	conn_resp->connect_resp_code = le32_get_bits(resp_msg->flags_len,
655 						     HTC_SVC_RESP_MSG_STATUS);
656 
657 	/* check response status */
658 	if (conn_resp->connect_resp_code != ATH12K_HTC_CONN_SVC_STATUS_SUCCESS) {
659 		ath12k_err(ab, "HTC Service %s connect request failed: 0x%x)\n",
660 			   htc_service_name(service_id),
661 		       conn_resp->connect_resp_code);
662 		return -EPROTO;
663 	}
664 
665 	assigned_eid = le32_get_bits(resp_msg->flags_len,
666 				     HTC_SVC_RESP_MSG_ENDPOINTID);
667 
668 	max_msg_size = le32_get_bits(resp_msg->flags_len,
669 				     HTC_SVC_RESP_MSG_MAXMSGSIZE);
670 
671 setup:
672 
673 	if (assigned_eid >= ATH12K_HTC_EP_COUNT)
674 		return -EPROTO;
675 
676 	if (max_msg_size == 0)
677 		return -EPROTO;
678 
679 	ep = &htc->endpoint[assigned_eid];
680 	ep->eid = assigned_eid;
681 
682 	if (ep->service_id != ATH12K_HTC_SVC_ID_UNUSED)
683 		return -EPROTO;
684 
685 	/* return assigned endpoint to caller */
686 	conn_resp->eid = assigned_eid;
687 	conn_resp->max_msg_len = le32_get_bits(resp_msg->flags_len,
688 					       HTC_SVC_RESP_MSG_MAXMSGSIZE);
689 
690 	/* setup the endpoint */
691 	ep->service_id = conn_req->service_id;
692 	ep->max_tx_queue_depth = conn_req->max_send_queue_depth;
693 	ep->max_ep_message_len = le32_get_bits(resp_msg->flags_len,
694 					       HTC_SVC_RESP_MSG_MAXMSGSIZE);
695 	ep->tx_credits = tx_alloc;
696 
697 	/* copy all the callbacks */
698 	ep->ep_ops = conn_req->ep_ops;
699 
700 	status = ath12k_hif_map_service_to_pipe(htc->ab,
701 						ep->service_id,
702 						&ep->ul_pipe_id,
703 						&ep->dl_pipe_id);
704 	if (status)
705 		return status;
706 
707 	ath12k_dbg(ab, ATH12K_DBG_BOOT,
708 		   "boot htc service '%s' ul pipe %d dl pipe %d eid %d ready\n",
709 		   htc_service_name(ep->service_id), ep->ul_pipe_id,
710 		   ep->dl_pipe_id, ep->eid);
711 
712 	if (disable_credit_flow_ctrl && ep->tx_credit_flow_enabled) {
713 		ep->tx_credit_flow_enabled = false;
714 		ath12k_dbg(ab, ATH12K_DBG_BOOT,
715 			   "boot htc service '%s' eid %d TX flow control disabled\n",
716 			   htc_service_name(ep->service_id), assigned_eid);
717 	}
718 
719 	return status;
720 }
721 
722 int ath12k_htc_start(struct ath12k_htc *htc)
723 {
724 	struct sk_buff *skb;
725 	int status;
726 	struct ath12k_base *ab = htc->ab;
727 	struct ath12k_htc_setup_complete_extended *msg;
728 
729 	skb = ath12k_htc_build_tx_ctrl_skb();
730 	if (!skb)
731 		return -ENOMEM;
732 
733 	skb_put(skb, sizeof(*msg));
734 	memset(skb->data, 0, skb->len);
735 
736 	msg = (struct ath12k_htc_setup_complete_extended *)skb->data;
737 	msg->msg_id = le32_encode_bits(ATH12K_HTC_MSG_SETUP_COMPLETE_EX_ID,
738 				       HTC_MSG_MESSAGEID);
739 
740 	ath12k_dbg(ab, ATH12K_DBG_HTC, "HTC is using TX credit flow control\n");
741 
742 	status = ath12k_htc_send(htc, ATH12K_HTC_EP_0, skb);
743 	if (status) {
744 		kfree_skb(skb);
745 		return status;
746 	}
747 
748 	return 0;
749 }
750 
751 int ath12k_htc_init(struct ath12k_base *ab)
752 {
753 	struct ath12k_htc *htc = &ab->htc;
754 	struct ath12k_htc_svc_conn_req conn_req = { };
755 	struct ath12k_htc_svc_conn_resp conn_resp = { };
756 	int ret;
757 
758 	spin_lock_init(&htc->tx_lock);
759 
760 	ath12k_htc_reset_endpoint_states(htc);
761 
762 	htc->ab = ab;
763 
764 	switch (ab->wmi_ab.preferred_hw_mode) {
765 	case WMI_HOST_HW_MODE_SINGLE:
766 		htc->wmi_ep_count = 1;
767 		break;
768 	case WMI_HOST_HW_MODE_DBS:
769 	case WMI_HOST_HW_MODE_DBS_OR_SBS:
770 		htc->wmi_ep_count = 2;
771 		break;
772 	case WMI_HOST_HW_MODE_DBS_SBS:
773 		htc->wmi_ep_count = 3;
774 		break;
775 	default:
776 		htc->wmi_ep_count = ab->hw_params->max_radios;
777 		break;
778 	}
779 
780 	/* setup our pseudo HTC control endpoint connection */
781 	conn_req.ep_ops.ep_tx_complete = ath12k_htc_control_tx_complete;
782 	conn_req.ep_ops.ep_rx_complete = ath12k_htc_control_rx_complete;
783 	conn_req.max_send_queue_depth = ATH12K_NUM_CONTROL_TX_BUFFERS;
784 	conn_req.service_id = ATH12K_HTC_SVC_ID_RSVD_CTRL;
785 
786 	/* connect fake service */
787 	ret = ath12k_htc_connect_service(htc, &conn_req, &conn_resp);
788 	if (ret) {
789 		ath12k_err(ab, "could not connect to htc service (%d)\n", ret);
790 		return ret;
791 	}
792 
793 	init_completion(&htc->ctl_resp);
794 
795 	return 0;
796 }
797