1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * ISHTP client logic
4 *
5 * Copyright (c) 2003-2016, Intel Corporation.
6 */
7
8#include <linux/slab.h>
9#include <linux/sched.h>
10#include <linux/wait.h>
11#include <linux/delay.h>
12#include <linux/dma-mapping.h>
13#include "hbm.h"
14#include "client.h"
15
16int ishtp_cl_get_tx_free_buffer_size(struct ishtp_cl *cl)
17{
18	unsigned long tx_free_flags;
19	int size;
20
21	spin_lock_irqsave(&cl->tx_free_list_spinlock, tx_free_flags);
22	size = cl->tx_ring_free_size * cl->device->fw_client->props.max_msg_length;
23	spin_unlock_irqrestore(&cl->tx_free_list_spinlock, tx_free_flags);
24
25	return size;
26}
27EXPORT_SYMBOL(ishtp_cl_get_tx_free_buffer_size);
28
29int ishtp_cl_get_tx_free_rings(struct ishtp_cl *cl)
30{
31	return cl->tx_ring_free_size;
32}
33EXPORT_SYMBOL(ishtp_cl_get_tx_free_rings);
34
35/**
36 * ishtp_read_list_flush() - Flush read queue
37 * @cl: ishtp client instance
38 *
39 * Used to remove all entries from read queue for a client
40 */
41static void ishtp_read_list_flush(struct ishtp_cl *cl)
42{
43	struct ishtp_cl_rb *rb;
44	struct ishtp_cl_rb *next;
45	unsigned long	flags;
46
47	spin_lock_irqsave(&cl->dev->read_list_spinlock, flags);
48	list_for_each_entry_safe(rb, next, &cl->dev->read_list.list, list)
49		if (rb->cl && ishtp_cl_cmp_id(cl, rb->cl)) {
50			list_del(&rb->list);
51			ishtp_io_rb_free(rb);
52		}
53	spin_unlock_irqrestore(&cl->dev->read_list_spinlock, flags);
54}
55
56/**
57 * ishtp_cl_flush_queues() - Flush all queues for a client
58 * @cl: ishtp client instance
59 *
60 * Used to remove all queues for a client. This is called when a client device
61 * needs reset due to error, S3 resume or during module removal
62 *
63 * Return: 0 on success else -EINVAL if device is NULL
64 */
65int ishtp_cl_flush_queues(struct ishtp_cl *cl)
66{
67	if (WARN_ON(!cl || !cl->dev))
68		return -EINVAL;
69
70	ishtp_read_list_flush(cl);
71
72	return 0;
73}
74EXPORT_SYMBOL(ishtp_cl_flush_queues);
75
76/**
77 * ishtp_cl_init() - Initialize all fields of a client device
78 * @cl: ishtp client instance
79 * @dev: ishtp device
80 *
81 * Initializes a client device fields: Init spinlocks, init queues etc.
82 * This function is called during new client creation
83 */
84static void ishtp_cl_init(struct ishtp_cl *cl, struct ishtp_device *dev)
85{
86	memset(cl, 0, sizeof(struct ishtp_cl));
87	init_waitqueue_head(&cl->wait_ctrl_res);
88	spin_lock_init(&cl->free_list_spinlock);
89	spin_lock_init(&cl->in_process_spinlock);
90	spin_lock_init(&cl->tx_list_spinlock);
91	spin_lock_init(&cl->tx_free_list_spinlock);
92	spin_lock_init(&cl->fc_spinlock);
93	INIT_LIST_HEAD(&cl->link);
94	cl->dev = dev;
95
96	INIT_LIST_HEAD(&cl->free_rb_list.list);
97	INIT_LIST_HEAD(&cl->tx_list.list);
98	INIT_LIST_HEAD(&cl->tx_free_list.list);
99	INIT_LIST_HEAD(&cl->in_process_list.list);
100
101	cl->rx_ring_size = CL_DEF_RX_RING_SIZE;
102	cl->tx_ring_size = CL_DEF_TX_RING_SIZE;
103	cl->tx_ring_free_size = cl->tx_ring_size;
104
105	/* dma */
106	cl->last_tx_path = CL_TX_PATH_IPC;
107	cl->last_dma_acked = 1;
108	cl->last_dma_addr = NULL;
109	cl->last_ipc_acked = 1;
110}
111
112/**
113 * ishtp_cl_allocate() - allocates client structure and sets it up.
114 * @dev: ishtp device
115 *
116 * Allocate memory for new client device and call to initialize each field.
117 *
118 * Return: The allocated client instance or NULL on failure
119 */
120struct ishtp_cl *ishtp_cl_allocate(struct ishtp_cl_device *cl_device)
121{
122	struct ishtp_cl *cl;
123
124	cl = kmalloc(sizeof(struct ishtp_cl), GFP_KERNEL);
125	if (!cl)
126		return NULL;
127
128	ishtp_cl_init(cl, cl_device->ishtp_dev);
129	return cl;
130}
131EXPORT_SYMBOL(ishtp_cl_allocate);
132
133/**
134 * ishtp_cl_free() - Frees a client device
135 * @cl: client device instance
136 *
137 * Frees a client device
138 */
139void	ishtp_cl_free(struct ishtp_cl *cl)
140{
141	struct ishtp_device *dev;
142	unsigned long flags;
143
144	if (!cl)
145		return;
146
147	dev = cl->dev;
148	if (!dev)
149		return;
150
151	spin_lock_irqsave(&dev->cl_list_lock, flags);
152	ishtp_cl_free_rx_ring(cl);
153	ishtp_cl_free_tx_ring(cl);
154	kfree(cl);
155	spin_unlock_irqrestore(&dev->cl_list_lock, flags);
156}
157EXPORT_SYMBOL(ishtp_cl_free);
158
159/**
160 * ishtp_cl_link() - Reserve a host id and link the client instance
161 * @cl: client device instance
162 *
163 * This allocates a single bit in the hostmap. This function will make sure
164 * that not many client sessions are opened at the same time. Once allocated
165 * the client device instance is added to the ishtp device in the current
166 * client list
167 *
168 * Return: 0 or error code on failure
169 */
170int ishtp_cl_link(struct ishtp_cl *cl)
171{
172	struct ishtp_device *dev;
173	unsigned long flags, flags_cl;
174	int id, ret = 0;
175
176	if (WARN_ON(!cl || !cl->dev))
177		return -EINVAL;
178
179	dev = cl->dev;
180
181	spin_lock_irqsave(&dev->device_lock, flags);
182
183	if (dev->open_handle_count >= ISHTP_MAX_OPEN_HANDLE_COUNT) {
184		ret = -EMFILE;
185		goto unlock_dev;
186	}
187
188	id = find_first_zero_bit(dev->host_clients_map, ISHTP_CLIENTS_MAX);
189
190	if (id >= ISHTP_CLIENTS_MAX) {
191		spin_unlock_irqrestore(&dev->device_lock, flags);
192		dev_err(&cl->device->dev, "id exceeded %d", ISHTP_CLIENTS_MAX);
193		return -ENOENT;
194	}
195
196	dev->open_handle_count++;
197	cl->host_client_id = id;
198	spin_lock_irqsave(&dev->cl_list_lock, flags_cl);
199	if (dev->dev_state != ISHTP_DEV_ENABLED) {
200		ret = -ENODEV;
201		goto unlock_cl;
202	}
203	list_add_tail(&cl->link, &dev->cl_list);
204	set_bit(id, dev->host_clients_map);
205	cl->state = ISHTP_CL_INITIALIZING;
206
207unlock_cl:
208	spin_unlock_irqrestore(&dev->cl_list_lock, flags_cl);
209unlock_dev:
210	spin_unlock_irqrestore(&dev->device_lock, flags);
211	return ret;
212}
213EXPORT_SYMBOL(ishtp_cl_link);
214
215/**
216 * ishtp_cl_unlink() - remove fw_cl from the client device list
217 * @cl: client device instance
218 *
219 * Remove a previously linked device to a ishtp device
220 */
221void ishtp_cl_unlink(struct ishtp_cl *cl)
222{
223	struct ishtp_device *dev;
224	struct ishtp_cl *pos;
225	unsigned long	flags;
226
227	/* don't shout on error exit path */
228	if (!cl || !cl->dev)
229		return;
230
231	dev = cl->dev;
232
233	spin_lock_irqsave(&dev->device_lock, flags);
234	if (dev->open_handle_count > 0) {
235		clear_bit(cl->host_client_id, dev->host_clients_map);
236		dev->open_handle_count--;
237	}
238	spin_unlock_irqrestore(&dev->device_lock, flags);
239
240	/*
241	 * This checks that 'cl' is actually linked into device's structure,
242	 * before attempting 'list_del'
243	 */
244	spin_lock_irqsave(&dev->cl_list_lock, flags);
245	list_for_each_entry(pos, &dev->cl_list, link)
246		if (cl->host_client_id == pos->host_client_id) {
247			list_del_init(&pos->link);
248			break;
249		}
250	spin_unlock_irqrestore(&dev->cl_list_lock, flags);
251}
252EXPORT_SYMBOL(ishtp_cl_unlink);
253
254/**
255 * ishtp_cl_disconnect() - Send disconnect request to firmware
256 * @cl: client device instance
257 *
258 * Send a disconnect request for a client to firmware.
259 *
260 * Return: 0 if successful disconnect response from the firmware or error
261 * code on failure
262 */
263int ishtp_cl_disconnect(struct ishtp_cl *cl)
264{
265	struct ishtp_device *dev;
266	int err;
267
268	if (WARN_ON(!cl || !cl->dev))
269		return -ENODEV;
270
271	dev = cl->dev;
272
273	dev->print_log(dev, "%s() state %d\n", __func__, cl->state);
274
275	if (cl->state != ISHTP_CL_DISCONNECTING) {
276		dev->print_log(dev, "%s() Disconnect in progress\n", __func__);
277		return 0;
278	}
279
280	if (ishtp_hbm_cl_disconnect_req(dev, cl)) {
281		dev->print_log(dev, "%s() Failed to disconnect\n", __func__);
282		dev_err(&cl->device->dev, "failed to disconnect.\n");
283		return -ENODEV;
284	}
285
286	err = wait_event_interruptible_timeout(cl->wait_ctrl_res,
287			(dev->dev_state != ISHTP_DEV_ENABLED ||
288			cl->state == ISHTP_CL_DISCONNECTED),
289			ishtp_secs_to_jiffies(ISHTP_CL_CONNECT_TIMEOUT));
290
291	/*
292	 * If FW reset arrived, this will happen. Don't check cl->,
293	 * as 'cl' may be freed already
294	 */
295	if (dev->dev_state != ISHTP_DEV_ENABLED) {
296		dev->print_log(dev, "%s() dev_state != ISHTP_DEV_ENABLED\n",
297			       __func__);
298		return -ENODEV;
299	}
300
301	if (cl->state == ISHTP_CL_DISCONNECTED) {
302		dev->print_log(dev, "%s() successful\n", __func__);
303		return 0;
304	}
305
306	return -ENODEV;
307}
308EXPORT_SYMBOL(ishtp_cl_disconnect);
309
310/**
311 * ishtp_cl_is_other_connecting() - Check other client is connecting
312 * @cl: client device instance
313 *
314 * Checks if other client with the same fw client id is connecting
315 *
316 * Return: true if other client is connected else false
317 */
318static bool ishtp_cl_is_other_connecting(struct ishtp_cl *cl)
319{
320	struct ishtp_device *dev;
321	struct ishtp_cl *pos;
322	unsigned long	flags;
323
324	if (WARN_ON(!cl || !cl->dev))
325		return false;
326
327	dev = cl->dev;
328	spin_lock_irqsave(&dev->cl_list_lock, flags);
329	list_for_each_entry(pos, &dev->cl_list, link) {
330		if ((pos->state == ISHTP_CL_CONNECTING) && (pos != cl) &&
331				cl->fw_client_id == pos->fw_client_id) {
332			spin_unlock_irqrestore(&dev->cl_list_lock, flags);
333			return true;
334		}
335	}
336	spin_unlock_irqrestore(&dev->cl_list_lock, flags);
337
338	return false;
339}
340
341/**
342 * ishtp_cl_connect() - Send connect request to firmware
343 * @cl: client device instance
344 *
345 * Send a connect request for a client to firmware. If successful it will
346 * RX and TX ring buffers
347 *
348 * Return: 0 if successful connect response from the firmware and able
349 * to bind and allocate ring buffers or error code on failure
350 */
351int ishtp_cl_connect(struct ishtp_cl *cl)
352{
353	struct ishtp_device *dev;
354	int rets;
355
356	if (WARN_ON(!cl || !cl->dev))
357		return -ENODEV;
358
359	dev = cl->dev;
360
361	dev->print_log(dev, "%s() current_state = %d\n", __func__, cl->state);
362
363	if (ishtp_cl_is_other_connecting(cl)) {
364		dev->print_log(dev, "%s() Busy\n", __func__);
365		return	-EBUSY;
366	}
367
368	if (ishtp_hbm_cl_connect_req(dev, cl)) {
369		dev->print_log(dev, "%s() HBM connect req fail\n", __func__);
370		return -ENODEV;
371	}
372
373	rets = wait_event_interruptible_timeout(cl->wait_ctrl_res,
374				(dev->dev_state == ISHTP_DEV_ENABLED &&
375				(cl->state == ISHTP_CL_CONNECTED ||
376				 cl->state == ISHTP_CL_DISCONNECTED)),
377				ishtp_secs_to_jiffies(
378					ISHTP_CL_CONNECT_TIMEOUT));
379	/*
380	 * If FW reset arrived, this will happen. Don't check cl->,
381	 * as 'cl' may be freed already
382	 */
383	if (dev->dev_state != ISHTP_DEV_ENABLED) {
384		dev->print_log(dev, "%s() dev_state != ISHTP_DEV_ENABLED\n",
385			       __func__);
386		return -EFAULT;
387	}
388
389	if (cl->state != ISHTP_CL_CONNECTED) {
390		dev->print_log(dev, "%s() state != ISHTP_CL_CONNECTED\n",
391			       __func__);
392		return -EFAULT;
393	}
394
395	rets = cl->status;
396	if (rets) {
397		dev->print_log(dev, "%s() Invalid status\n", __func__);
398		return rets;
399	}
400
401	rets = ishtp_cl_device_bind(cl);
402	if (rets) {
403		dev->print_log(dev, "%s() Bind error\n", __func__);
404		ishtp_cl_disconnect(cl);
405		return rets;
406	}
407
408	rets = ishtp_cl_alloc_rx_ring(cl);
409	if (rets) {
410		dev->print_log(dev, "%s() Alloc RX ring failed\n", __func__);
411		/* if failed allocation, disconnect */
412		ishtp_cl_disconnect(cl);
413		return rets;
414	}
415
416	rets = ishtp_cl_alloc_tx_ring(cl);
417	if (rets) {
418		dev->print_log(dev, "%s() Alloc TX ring failed\n", __func__);
419		/* if failed allocation, disconnect */
420		ishtp_cl_free_rx_ring(cl);
421		ishtp_cl_disconnect(cl);
422		return rets;
423	}
424
425	/* Upon successful connection and allocation, emit flow-control */
426	rets = ishtp_cl_read_start(cl);
427
428	dev->print_log(dev, "%s() successful\n", __func__);
429
430	return rets;
431}
432EXPORT_SYMBOL(ishtp_cl_connect);
433
434/**
435 * ishtp_cl_read_start() - Prepare to read client message
436 * @cl: client device instance
437 *
438 * Get a free buffer from pool of free read buffers and add to read buffer
439 * pool to add contents. Send a flow control request to firmware to be able
440 * send next message.
441 *
442 * Return: 0 if successful or error code on failure
443 */
444int ishtp_cl_read_start(struct ishtp_cl *cl)
445{
446	struct ishtp_device *dev;
447	struct ishtp_cl_rb *rb;
448	int rets;
449	int i;
450	unsigned long	flags;
451	unsigned long	dev_flags;
452
453	if (WARN_ON(!cl || !cl->dev))
454		return -ENODEV;
455
456	dev = cl->dev;
457
458	if (cl->state != ISHTP_CL_CONNECTED)
459		return -ENODEV;
460
461	if (dev->dev_state != ISHTP_DEV_ENABLED)
462		return -ENODEV;
463
464	i = ishtp_fw_cl_by_id(dev, cl->fw_client_id);
465	if (i < 0) {
466		dev_err(&cl->device->dev, "no such fw client %d\n",
467			cl->fw_client_id);
468		return -ENODEV;
469	}
470
471	/* The current rb is the head of the free rb list */
472	spin_lock_irqsave(&cl->free_list_spinlock, flags);
473	if (list_empty(&cl->free_rb_list.list)) {
474		dev_warn(&cl->device->dev,
475			 "[ishtp-ish] Rx buffers pool is empty\n");
476		rets = -ENOMEM;
477		rb = NULL;
478		spin_unlock_irqrestore(&cl->free_list_spinlock, flags);
479		goto out;
480	}
481	rb = list_entry(cl->free_rb_list.list.next, struct ishtp_cl_rb, list);
482	list_del_init(&rb->list);
483	spin_unlock_irqrestore(&cl->free_list_spinlock, flags);
484
485	rb->cl = cl;
486	rb->buf_idx = 0;
487
488	INIT_LIST_HEAD(&rb->list);
489	rets = 0;
490
491	/*
492	 * This must be BEFORE sending flow control -
493	 * response in ISR may come too fast...
494	 */
495	spin_lock_irqsave(&dev->read_list_spinlock, dev_flags);
496	list_add_tail(&rb->list, &dev->read_list.list);
497	spin_unlock_irqrestore(&dev->read_list_spinlock, dev_flags);
498	if (ishtp_hbm_cl_flow_control_req(dev, cl)) {
499		rets = -ENODEV;
500		goto out;
501	}
502out:
503	/* if ishtp_hbm_cl_flow_control_req failed, return rb to free list */
504	if (rets && rb) {
505		spin_lock_irqsave(&dev->read_list_spinlock, dev_flags);
506		list_del(&rb->list);
507		spin_unlock_irqrestore(&dev->read_list_spinlock, dev_flags);
508
509		spin_lock_irqsave(&cl->free_list_spinlock, flags);
510		list_add_tail(&rb->list, &cl->free_rb_list.list);
511		spin_unlock_irqrestore(&cl->free_list_spinlock, flags);
512	}
513	return rets;
514}
515
516/**
517 * ishtp_cl_send() - Send a message to firmware
518 * @cl: client device instance
519 * @buf: message buffer
520 * @length: length of message
521 *
522 * If the client is correct state to send message, this function gets a buffer
523 * from tx ring buffers, copy the message data and call to send the message
524 * using ishtp_cl_send_msg()
525 *
526 * Return: 0 if successful or error code on failure
527 */
528int ishtp_cl_send(struct ishtp_cl *cl, uint8_t *buf, size_t length)
529{
530	struct ishtp_device	*dev;
531	int	id;
532	struct ishtp_cl_tx_ring	*cl_msg;
533	int	have_msg_to_send = 0;
534	unsigned long	tx_flags, tx_free_flags;
535
536	if (WARN_ON(!cl || !cl->dev))
537		return -ENODEV;
538
539	dev = cl->dev;
540
541	if (cl->state != ISHTP_CL_CONNECTED) {
542		++cl->err_send_msg;
543		return -EPIPE;
544	}
545
546	if (dev->dev_state != ISHTP_DEV_ENABLED) {
547		++cl->err_send_msg;
548		return -ENODEV;
549	}
550
551	/* Check if we have fw client device */
552	id = ishtp_fw_cl_by_id(dev, cl->fw_client_id);
553	if (id < 0) {
554		++cl->err_send_msg;
555		return -ENOENT;
556	}
557
558	if (length > dev->fw_clients[id].props.max_msg_length) {
559		++cl->err_send_msg;
560		return -EMSGSIZE;
561	}
562
563	/* No free bufs */
564	spin_lock_irqsave(&cl->tx_free_list_spinlock, tx_free_flags);
565	if (list_empty(&cl->tx_free_list.list)) {
566		spin_unlock_irqrestore(&cl->tx_free_list_spinlock,
567			tx_free_flags);
568		++cl->err_send_msg;
569		return	-ENOMEM;
570	}
571
572	cl_msg = list_first_entry(&cl->tx_free_list.list,
573		struct ishtp_cl_tx_ring, list);
574	if (!cl_msg->send_buf.data) {
575		spin_unlock_irqrestore(&cl->tx_free_list_spinlock,
576			tx_free_flags);
577		return	-EIO;
578		/* Should not happen, as free list is pre-allocated */
579	}
580	/*
581	 * This is safe, as 'length' is already checked for not exceeding
582	 * max ISHTP message size per client
583	 */
584	list_del_init(&cl_msg->list);
585	--cl->tx_ring_free_size;
586
587	spin_unlock_irqrestore(&cl->tx_free_list_spinlock, tx_free_flags);
588	memcpy(cl_msg->send_buf.data, buf, length);
589	cl_msg->send_buf.size = length;
590	spin_lock_irqsave(&cl->tx_list_spinlock, tx_flags);
591	have_msg_to_send = !list_empty(&cl->tx_list.list);
592	list_add_tail(&cl_msg->list, &cl->tx_list.list);
593	spin_unlock_irqrestore(&cl->tx_list_spinlock, tx_flags);
594
595	if (!have_msg_to_send && cl->ishtp_flow_ctrl_creds > 0)
596		ishtp_cl_send_msg(dev, cl);
597
598	return	0;
599}
600EXPORT_SYMBOL(ishtp_cl_send);
601
602/**
603 * ishtp_cl_read_complete() - read complete
604 * @rb: Pointer to client request block
605 *
606 * If the message is completely received call ishtp_cl_bus_rx_event()
607 * to process message
608 */
609static void ishtp_cl_read_complete(struct ishtp_cl_rb *rb)
610{
611	unsigned long	flags;
612	int	schedule_work_flag = 0;
613	struct ishtp_cl	*cl = rb->cl;
614
615	spin_lock_irqsave(&cl->in_process_spinlock, flags);
616	/*
617	 * if in-process list is empty, then need to schedule
618	 * the processing thread
619	 */
620	schedule_work_flag = list_empty(&cl->in_process_list.list);
621	list_add_tail(&rb->list, &cl->in_process_list.list);
622	spin_unlock_irqrestore(&cl->in_process_spinlock, flags);
623
624	if (schedule_work_flag)
625		ishtp_cl_bus_rx_event(cl->device);
626}
627
628/**
629 * ipc_tx_send() - IPC tx send function
630 * @prm: Pointer to client device instance
631 *
632 * Send message over IPC. Message will be split into fragments
633 * if message size is bigger than IPC FIFO size, and all
634 * fragments will be sent one by one.
635 */
636static void ipc_tx_send(void *prm)
637{
638	struct ishtp_cl	*cl = prm;
639	struct ishtp_cl_tx_ring	*cl_msg;
640	size_t	rem;
641	struct ishtp_device	*dev = (cl ? cl->dev : NULL);
642	struct ishtp_msg_hdr	ishtp_hdr;
643	unsigned long	tx_flags, tx_free_flags;
644	unsigned char	*pmsg;
645
646	if (!dev)
647		return;
648
649	/*
650	 * Other conditions if some critical error has
651	 * occurred before this callback is called
652	 */
653	if (dev->dev_state != ISHTP_DEV_ENABLED)
654		return;
655
656	if (cl->state != ISHTP_CL_CONNECTED)
657		return;
658
659	spin_lock_irqsave(&cl->tx_list_spinlock, tx_flags);
660	if (list_empty(&cl->tx_list.list)) {
661		spin_unlock_irqrestore(&cl->tx_list_spinlock, tx_flags);
662		return;
663	}
664
665	if (cl->ishtp_flow_ctrl_creds != 1 && !cl->sending) {
666		spin_unlock_irqrestore(&cl->tx_list_spinlock, tx_flags);
667		return;
668	}
669
670	if (!cl->sending) {
671		--cl->ishtp_flow_ctrl_creds;
672		cl->last_ipc_acked = 0;
673		cl->last_tx_path = CL_TX_PATH_IPC;
674		cl->sending = 1;
675	}
676
677	cl_msg = list_entry(cl->tx_list.list.next, struct ishtp_cl_tx_ring,
678			    list);
679	rem = cl_msg->send_buf.size - cl->tx_offs;
680
681	while (rem > 0) {
682		ishtp_hdr.host_addr = cl->host_client_id;
683		ishtp_hdr.fw_addr = cl->fw_client_id;
684		ishtp_hdr.reserved = 0;
685		pmsg = cl_msg->send_buf.data + cl->tx_offs;
686
687		if (rem <= dev->mtu) {
688			/* Last fragment or only one packet */
689			ishtp_hdr.length = rem;
690			ishtp_hdr.msg_complete = 1;
691			/* Submit to IPC queue with no callback */
692			ishtp_write_message(dev, &ishtp_hdr, pmsg);
693			cl->tx_offs = 0;
694			cl->sending = 0;
695
696			break;
697		} else {
698			/* Send ipc fragment */
699			ishtp_hdr.length = dev->mtu;
700			ishtp_hdr.msg_complete = 0;
701			/* All fregments submitted to IPC queue with no callback */
702			ishtp_write_message(dev, &ishtp_hdr, pmsg);
703			cl->tx_offs += dev->mtu;
704			rem = cl_msg->send_buf.size - cl->tx_offs;
705		}
706	}
707
708	list_del_init(&cl_msg->list);
709	spin_unlock_irqrestore(&cl->tx_list_spinlock, tx_flags);
710
711	spin_lock_irqsave(&cl->tx_free_list_spinlock, tx_free_flags);
712	list_add_tail(&cl_msg->list, &cl->tx_free_list.list);
713	++cl->tx_ring_free_size;
714	spin_unlock_irqrestore(&cl->tx_free_list_spinlock,
715		tx_free_flags);
716}
717
718/**
719 * ishtp_cl_send_msg_ipc() -Send message using IPC
720 * @dev: ISHTP device instance
721 * @cl: Pointer to client device instance
722 *
723 * Send message over IPC not using DMA
724 */
725static void ishtp_cl_send_msg_ipc(struct ishtp_device *dev,
726				  struct ishtp_cl *cl)
727{
728	/* If last DMA message wasn't acked yet, leave this one in Tx queue */
729	if (cl->last_tx_path == CL_TX_PATH_DMA && cl->last_dma_acked == 0)
730		return;
731
732	cl->tx_offs = 0;
733	ipc_tx_send(cl);
734	++cl->send_msg_cnt_ipc;
735}
736
737/**
738 * ishtp_cl_send_msg_dma() -Send message using DMA
739 * @dev: ISHTP device instance
740 * @cl: Pointer to client device instance
741 *
742 * Send message using DMA
743 */
744static void ishtp_cl_send_msg_dma(struct ishtp_device *dev,
745	struct ishtp_cl *cl)
746{
747	struct ishtp_msg_hdr	hdr;
748	struct dma_xfer_hbm	dma_xfer;
749	unsigned char	*msg_addr;
750	int off;
751	struct ishtp_cl_tx_ring	*cl_msg;
752	unsigned long tx_flags, tx_free_flags;
753
754	/* If last IPC message wasn't acked yet, leave this one in Tx queue */
755	if (cl->last_tx_path == CL_TX_PATH_IPC && cl->last_ipc_acked == 0)
756		return;
757
758	spin_lock_irqsave(&cl->tx_list_spinlock, tx_flags);
759	if (list_empty(&cl->tx_list.list)) {
760		spin_unlock_irqrestore(&cl->tx_list_spinlock, tx_flags);
761		return;
762	}
763
764	cl_msg = list_entry(cl->tx_list.list.next, struct ishtp_cl_tx_ring,
765		list);
766
767	msg_addr = ishtp_cl_get_dma_send_buf(dev, cl_msg->send_buf.size);
768	if (!msg_addr) {
769		spin_unlock_irqrestore(&cl->tx_list_spinlock, tx_flags);
770		if (dev->transfer_path == CL_TX_PATH_DEFAULT)
771			ishtp_cl_send_msg_ipc(dev, cl);
772		return;
773	}
774
775	list_del_init(&cl_msg->list);	/* Must be before write */
776	spin_unlock_irqrestore(&cl->tx_list_spinlock, tx_flags);
777
778	--cl->ishtp_flow_ctrl_creds;
779	cl->last_dma_acked = 0;
780	cl->last_dma_addr = msg_addr;
781	cl->last_tx_path = CL_TX_PATH_DMA;
782
783	/* write msg to dma buf */
784	memcpy(msg_addr, cl_msg->send_buf.data, cl_msg->send_buf.size);
785
786	/* send dma_xfer hbm msg */
787	off = msg_addr - (unsigned char *)dev->ishtp_host_dma_tx_buf;
788	ishtp_hbm_hdr(&hdr, sizeof(struct dma_xfer_hbm));
789	dma_xfer.hbm = DMA_XFER;
790	dma_xfer.fw_client_id = cl->fw_client_id;
791	dma_xfer.host_client_id = cl->host_client_id;
792	dma_xfer.reserved = 0;
793	dma_xfer.msg_addr = dev->ishtp_host_dma_tx_buf_phys + off;
794	dma_xfer.msg_length = cl_msg->send_buf.size;
795	dma_xfer.reserved2 = 0;
796	ishtp_write_message(dev, &hdr, (unsigned char *)&dma_xfer);
797	spin_lock_irqsave(&cl->tx_free_list_spinlock, tx_free_flags);
798	list_add_tail(&cl_msg->list, &cl->tx_free_list.list);
799	++cl->tx_ring_free_size;
800	spin_unlock_irqrestore(&cl->tx_free_list_spinlock, tx_free_flags);
801	++cl->send_msg_cnt_dma;
802}
803
804/**
805 * ishtp_cl_send_msg() -Send message using DMA or IPC
806 * @dev: ISHTP device instance
807 * @cl: Pointer to client device instance
808 *
809 * Send message using DMA or IPC based on transfer_path
810 */
811void ishtp_cl_send_msg(struct ishtp_device *dev, struct ishtp_cl *cl)
812{
813	if (dev->transfer_path == CL_TX_PATH_DMA)
814		ishtp_cl_send_msg_dma(dev, cl);
815	else
816		ishtp_cl_send_msg_ipc(dev, cl);
817}
818
819/**
820 * recv_ishtp_cl_msg() -Receive client message
821 * @dev: ISHTP device instance
822 * @ishtp_hdr: Pointer to message header
823 *
824 * Receive and dispatch ISHTP client messages. This function executes in ISR
825 * or work queue context
826 */
827void recv_ishtp_cl_msg(struct ishtp_device *dev,
828		       struct ishtp_msg_hdr *ishtp_hdr)
829{
830	struct ishtp_cl *cl;
831	struct ishtp_cl_rb *rb;
832	struct ishtp_cl_rb *new_rb;
833	unsigned char *buffer = NULL;
834	struct ishtp_cl_rb *complete_rb = NULL;
835	unsigned long	flags;
836	int	rb_count;
837
838	if (ishtp_hdr->reserved) {
839		dev_err(dev->devc, "corrupted message header.\n");
840		goto	eoi;
841	}
842
843	if (ishtp_hdr->length > IPC_PAYLOAD_SIZE) {
844		dev_err(dev->devc,
845			"ISHTP message length in hdr exceeds IPC MTU\n");
846		goto	eoi;
847	}
848
849	spin_lock_irqsave(&dev->read_list_spinlock, flags);
850	rb_count = -1;
851	list_for_each_entry(rb, &dev->read_list.list, list) {
852		++rb_count;
853		cl = rb->cl;
854		if (!cl || !(cl->host_client_id == ishtp_hdr->host_addr &&
855				cl->fw_client_id == ishtp_hdr->fw_addr) ||
856				!(cl->state == ISHTP_CL_CONNECTED))
857			continue;
858
859		 /* If no Rx buffer is allocated, disband the rb */
860		if (rb->buffer.size == 0 || rb->buffer.data == NULL) {
861			spin_unlock_irqrestore(&dev->read_list_spinlock, flags);
862			dev_err(&cl->device->dev,
863				"Rx buffer is not allocated.\n");
864			list_del(&rb->list);
865			ishtp_io_rb_free(rb);
866			cl->status = -ENOMEM;
867			goto	eoi;
868		}
869
870		/*
871		 * If message buffer overflown (exceeds max. client msg
872		 * size, drop message and return to free buffer.
873		 * Do we need to disconnect such a client? (We don't send
874		 * back FC, so communication will be stuck anyway)
875		 */
876		if (rb->buffer.size < ishtp_hdr->length + rb->buf_idx) {
877			spin_unlock_irqrestore(&dev->read_list_spinlock, flags);
878			dev_err(&cl->device->dev,
879				"message overflow. size %d len %d idx %ld\n",
880				rb->buffer.size, ishtp_hdr->length,
881				rb->buf_idx);
882			list_del(&rb->list);
883			ishtp_cl_io_rb_recycle(rb);
884			cl->status = -EIO;
885			goto	eoi;
886		}
887
888		buffer = rb->buffer.data + rb->buf_idx;
889		dev->ops->ishtp_read(dev, buffer, ishtp_hdr->length);
890
891		rb->buf_idx += ishtp_hdr->length;
892		if (ishtp_hdr->msg_complete) {
893			/* Last fragment in message - it's complete */
894			cl->status = 0;
895			list_del(&rb->list);
896			complete_rb = rb;
897
898			--cl->out_flow_ctrl_creds;
899			/*
900			 * the whole msg arrived, send a new FC, and add a new
901			 * rb buffer for the next coming msg
902			 */
903			spin_lock(&cl->free_list_spinlock);
904
905			if (!list_empty(&cl->free_rb_list.list)) {
906				new_rb = list_entry(cl->free_rb_list.list.next,
907					struct ishtp_cl_rb, list);
908				list_del_init(&new_rb->list);
909				spin_unlock(&cl->free_list_spinlock);
910				new_rb->cl = cl;
911				new_rb->buf_idx = 0;
912				INIT_LIST_HEAD(&new_rb->list);
913				list_add_tail(&new_rb->list,
914					&dev->read_list.list);
915
916				ishtp_hbm_cl_flow_control_req(dev, cl);
917			} else {
918				spin_unlock(&cl->free_list_spinlock);
919			}
920		}
921		/* One more fragment in message (even if this was last) */
922		++cl->recv_msg_num_frags;
923
924		/*
925		 * We can safely break here (and in BH too),
926		 * a single input message can go only to a single request!
927		 */
928		break;
929	}
930
931	spin_unlock_irqrestore(&dev->read_list_spinlock, flags);
932	/* If it's nobody's message, just read and discard it */
933	if (!buffer) {
934		uint8_t	rd_msg_buf[ISHTP_RD_MSG_BUF_SIZE];
935
936		dev_err(dev->devc, "Dropped Rx msg - no request\n");
937		dev->ops->ishtp_read(dev, rd_msg_buf, ishtp_hdr->length);
938		goto	eoi;
939	}
940
941	if (complete_rb) {
942		cl = complete_rb->cl;
943		cl->ts_rx = ktime_get();
944		++cl->recv_msg_cnt_ipc;
945		ishtp_cl_read_complete(complete_rb);
946	}
947eoi:
948	return;
949}
950
951/**
952 * recv_ishtp_cl_msg_dma() -Receive client message
953 * @dev: ISHTP device instance
954 * @msg: message pointer
955 * @hbm: hbm buffer
956 *
957 * Receive and dispatch ISHTP client messages using DMA. This function executes
958 * in ISR or work queue context
959 */
960void recv_ishtp_cl_msg_dma(struct ishtp_device *dev, void *msg,
961			   struct dma_xfer_hbm *hbm)
962{
963	struct ishtp_cl *cl;
964	struct ishtp_cl_rb *rb;
965	struct ishtp_cl_rb *new_rb;
966	unsigned char *buffer = NULL;
967	struct ishtp_cl_rb *complete_rb = NULL;
968	unsigned long	flags;
969
970	spin_lock_irqsave(&dev->read_list_spinlock, flags);
971
972	list_for_each_entry(rb, &dev->read_list.list, list) {
973		cl = rb->cl;
974		if (!cl || !(cl->host_client_id == hbm->host_client_id &&
975				cl->fw_client_id == hbm->fw_client_id) ||
976				!(cl->state == ISHTP_CL_CONNECTED))
977			continue;
978
979		/*
980		 * If no Rx buffer is allocated, disband the rb
981		 */
982		if (rb->buffer.size == 0 || rb->buffer.data == NULL) {
983			spin_unlock_irqrestore(&dev->read_list_spinlock, flags);
984			dev_err(&cl->device->dev,
985				"response buffer is not allocated.\n");
986			list_del(&rb->list);
987			ishtp_io_rb_free(rb);
988			cl->status = -ENOMEM;
989			goto	eoi;
990		}
991
992		/*
993		 * If message buffer overflown (exceeds max. client msg
994		 * size, drop message and return to free buffer.
995		 * Do we need to disconnect such a client? (We don't send
996		 * back FC, so communication will be stuck anyway)
997		 */
998		if (rb->buffer.size < hbm->msg_length) {
999			spin_unlock_irqrestore(&dev->read_list_spinlock, flags);
1000			dev_err(&cl->device->dev,
1001				"message overflow. size %d len %d idx %ld\n",
1002				rb->buffer.size, hbm->msg_length, rb->buf_idx);
1003			list_del(&rb->list);
1004			ishtp_cl_io_rb_recycle(rb);
1005			cl->status = -EIO;
1006			goto	eoi;
1007		}
1008
1009		buffer = rb->buffer.data;
1010		memcpy(buffer, msg, hbm->msg_length);
1011		rb->buf_idx = hbm->msg_length;
1012
1013		/* Last fragment in message - it's complete */
1014		cl->status = 0;
1015		list_del(&rb->list);
1016		complete_rb = rb;
1017
1018		--cl->out_flow_ctrl_creds;
1019		/*
1020		 * the whole msg arrived, send a new FC, and add a new
1021		 * rb buffer for the next coming msg
1022		 */
1023		spin_lock(&cl->free_list_spinlock);
1024
1025		if (!list_empty(&cl->free_rb_list.list)) {
1026			new_rb = list_entry(cl->free_rb_list.list.next,
1027				struct ishtp_cl_rb, list);
1028			list_del_init(&new_rb->list);
1029			spin_unlock(&cl->free_list_spinlock);
1030			new_rb->cl = cl;
1031			new_rb->buf_idx = 0;
1032			INIT_LIST_HEAD(&new_rb->list);
1033			list_add_tail(&new_rb->list,
1034				&dev->read_list.list);
1035
1036			ishtp_hbm_cl_flow_control_req(dev, cl);
1037		} else {
1038			spin_unlock(&cl->free_list_spinlock);
1039		}
1040
1041		/* One more fragment in message (this is always last) */
1042		++cl->recv_msg_num_frags;
1043
1044		/*
1045		 * We can safely break here (and in BH too),
1046		 * a single input message can go only to a single request!
1047		 */
1048		break;
1049	}
1050
1051	spin_unlock_irqrestore(&dev->read_list_spinlock, flags);
1052	/* If it's nobody's message, just read and discard it */
1053	if (!buffer) {
1054		dev_err(dev->devc, "Dropped Rx (DMA) msg - no request\n");
1055		goto	eoi;
1056	}
1057
1058	if (complete_rb) {
1059		cl = complete_rb->cl;
1060		cl->ts_rx = ktime_get();
1061		++cl->recv_msg_cnt_dma;
1062		ishtp_cl_read_complete(complete_rb);
1063	}
1064eoi:
1065	return;
1066}
1067
1068void *ishtp_get_client_data(struct ishtp_cl *cl)
1069{
1070	return cl->client_data;
1071}
1072EXPORT_SYMBOL(ishtp_get_client_data);
1073
1074void ishtp_set_client_data(struct ishtp_cl *cl, void *data)
1075{
1076	cl->client_data = data;
1077}
1078EXPORT_SYMBOL(ishtp_set_client_data);
1079
1080struct ishtp_device *ishtp_get_ishtp_device(struct ishtp_cl *cl)
1081{
1082	return cl->dev;
1083}
1084EXPORT_SYMBOL(ishtp_get_ishtp_device);
1085
1086void ishtp_set_tx_ring_size(struct ishtp_cl *cl, int size)
1087{
1088	cl->tx_ring_size = size;
1089}
1090EXPORT_SYMBOL(ishtp_set_tx_ring_size);
1091
1092void ishtp_set_rx_ring_size(struct ishtp_cl *cl, int size)
1093{
1094	cl->rx_ring_size = size;
1095}
1096EXPORT_SYMBOL(ishtp_set_rx_ring_size);
1097
1098void ishtp_set_connection_state(struct ishtp_cl *cl, int state)
1099{
1100	cl->state = state;
1101}
1102EXPORT_SYMBOL(ishtp_set_connection_state);
1103
1104void ishtp_cl_set_fw_client_id(struct ishtp_cl *cl, int fw_client_id)
1105{
1106	cl->fw_client_id = fw_client_id;
1107}
1108EXPORT_SYMBOL(ishtp_cl_set_fw_client_id);
1109