[deliverable/linux.git] / drivers / media / video / cx18 / cx18-queue.c

/*
 *  cx18 buffer queues
 *
 *  Derived from ivtv-queue.c
 *
 *  Copyright (C) 2007  Hans Verkuil <hverkuil@xs4all.nl>
 *  Copyright (C) 2008  Andy Walls <awalls@radix.net>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
 *  02111-1307  USA
 */

#include "cx18-driver.h"
#include "cx18-queue.h"
#include "cx18-streams.h"
#include "cx18-scb.h"

void cx18_buf_swap(struct cx18_buffer *buf)
{
	int i;

	for (i = 0; i < buf->bytesused; i += 4)
		swab32s((u32 *)(buf->buf + i));
}

void cx18_queue_init(struct cx18_queue *q)
{
	INIT_LIST_HEAD(&q->list);
	atomic_set(&q->buffers, 0);
	q->bytesused = 0;
}

struct cx18_queue *_cx18_enqueue(struct cx18_stream *s, struct cx18_buffer *buf,
				 struct cx18_queue *q, int to_front)
{
	/* clear the buffer if it is not to be enqueued to the full queue */
	if (q != &s->q_full) {
		buf->bytesused = 0;
		buf->readpos = 0;
		buf->b_flags = 0;
		buf->skipped = 0;
	}

	/* q_busy is restricted to a max buffer count imposed by firmware */
	if (q == &s->q_busy &&
	    atomic_read(&q->buffers) >= CX18_MAX_FW_MDLS_PER_STREAM)
		q = &s->q_free;

	spin_lock(&q->lock);

	if (to_front)
		list_add(&buf->list, &q->list); /* LIFO */
	else
		list_add_tail(&buf->list, &q->list); /* FIFO */
	q->bytesused += buf->bytesused - buf->readpos;
	atomic_inc(&q->buffers);

	spin_unlock(&q->lock);
	return q;
}

struct cx18_buffer *cx18_dequeue(struct cx18_stream *s, struct cx18_queue *q)
{
	struct cx18_buffer *buf = NULL;

	spin_lock(&q->lock);
	if (!list_empty(&q->list)) {
		buf = list_first_entry(&q->list, struct cx18_buffer, list);
		list_del_init(&buf->list);
		q->bytesused -= buf->bytesused - buf->readpos;
		buf->skipped = 0;
		atomic_dec(&q->buffers);
	}
	spin_unlock(&q->lock);
	return buf;
}

struct cx18_buffer *cx18_queue_get_buf(struct cx18_stream *s, u32 id,
	u32 bytesused)
{
	struct cx18 *cx = s->cx;
	struct cx18_buffer *buf;
	struct cx18_buffer *tmp;
	struct cx18_buffer *ret = NULL;
	LIST_HEAD(sweep_up);

	/*
	 * We don't have to acquire multiple q locks here, because we are
	 * serialized by the single threaded work handler.
	 * Buffers from the firmware will thus remain in order as
	 * they are moved from q_busy to q_full or to the dvb ring buffer.
	 */
	spin_lock(&s->q_busy.lock);
	list_for_each_entry_safe(buf, tmp, &s->q_busy.list, list) {
		/*
		 * We should find what the firmware told us is done,
		 * right at the front of the queue.  If we don't, we likely have
		 * missed a buffer done message from the firmware.
		 * Once we skip a buffer repeatedly, relative to the size of
		 * q_busy, we have high confidence we've missed it.
		 */
		if (buf->id != id) {
			buf->skipped++;
			if (buf->skipped >= atomic_read(&s->q_busy.buffers)-1) {
				/* buffer must have fallen out of rotation */
				CX18_WARN("Skipped %s, buffer %d, %d "
					  "times - it must have dropped out of "
					  "rotation\n", s->name, buf->id,
					  buf->skipped);
				/* Sweep it up to put it back into rotation */
				list_move_tail(&buf->list, &sweep_up);
				atomic_dec(&s->q_busy.buffers);
			}
			continue;
		}
		/*
		 * We pull the desired buffer off of the queue here.  Something
		 * will have to put it back on a queue later.
		 */
		list_del_init(&buf->list);
		atomic_dec(&s->q_busy.buffers);
		ret = buf;
		break;
	}
	spin_unlock(&s->q_busy.lock);

	/*
	 * We found the buffer for which we were looking.  Get it ready for
	 * the caller to put on q_full or in the dvb ring buffer.
	 */
	if (ret != NULL) {
		ret->bytesused = bytesused;
		ret->skipped = 0;
		/* readpos and b_flags were 0'ed when the buf went on q_busy */
		cx18_buf_sync_for_cpu(s, ret);
		if (s->type != CX18_ENC_STREAM_TYPE_TS)
			set_bit(CX18_F_B_NEED_BUF_SWAP, &ret->b_flags);
	}

	/* Put any buffers the firmware is ignoring back into normal rotation */
	list_for_each_entry_safe(buf, tmp, &sweep_up, list) {
		list_del_init(&buf->list);
		cx18_enqueue(s, buf, &s->q_free);
	}
	return ret;
}

/* Move all buffers of a queue to q_free, while flushing the buffers */
static void cx18_queue_flush(struct cx18_stream *s, struct cx18_queue *q)
{
	struct cx18_buffer *buf;

	if (q == &s->q_free)
		return;

	spin_lock(&q->lock);
	while (!list_empty(&q->list)) {
		buf = list_first_entry(&q->list, struct cx18_buffer, list);
		list_move_tail(&buf->list, &s->q_free.list);
		buf->bytesused = buf->readpos = buf->b_flags = buf->skipped = 0;
		atomic_inc(&s->q_free.buffers);
	}
	cx18_queue_init(q);
	spin_unlock(&q->lock);
}

void cx18_flush_queues(struct cx18_stream *s)
{
	cx18_queue_flush(s, &s->q_busy);
	cx18_queue_flush(s, &s->q_full);
}

int cx18_stream_alloc(struct cx18_stream *s)
{
	struct cx18 *cx = s->cx;
	int i;

	if (s->buffers == 0)
		return 0;

	CX18_DEBUG_INFO("Allocate %s stream: %d x %d buffers (%dkB total)\n",
		s->name, s->buffers, s->buf_size,
		s->buffers * s->buf_size / 1024);

	if (((char __iomem *)&cx->scb->cpu_mdl[cx->mdl_offset + s->buffers] -
				(char __iomem *)cx->scb) > SCB_RESERVED_SIZE) {
		unsigned bufsz = (((char __iomem *)cx->scb) + SCB_RESERVED_SIZE -
					((char __iomem *)cx->scb->cpu_mdl));

		CX18_ERR("Too many buffers, cannot fit in SCB area\n");
		CX18_ERR("Max buffers = %zd\n",
			bufsz / sizeof(struct cx18_mdl));
		return -ENOMEM;
	}

	s->mdl_offset = cx->mdl_offset;

	/* allocate stream buffers. Initially all buffers are in q_free. */
	for (i = 0; i < s->buffers; i++) {
		struct cx18_buffer *buf = kzalloc(sizeof(struct cx18_buffer),
						GFP_KERNEL|__GFP_NOWARN);

		if (buf == NULL)
			break;
		buf->buf = kmalloc(s->buf_size, GFP_KERNEL|__GFP_NOWARN);
		if (buf->buf == NULL) {
			kfree(buf);
			break;
		}
		buf->id = cx->buffer_id++;
		INIT_LIST_HEAD(&buf->list);
		buf->dma_handle = pci_map_single(s->cx->pci_dev,
				buf->buf, s->buf_size, s->dma);
		cx18_buf_sync_for_cpu(s, buf);
		cx18_enqueue(s, buf, &s->q_free);
	}
	if (i == s->buffers) {
		cx->mdl_offset += s->buffers;
		return 0;
	}
	CX18_ERR("Couldn't allocate buffers for %s stream\n", s->name);
	cx18_stream_free(s);
	return -ENOMEM;
}

void cx18_stream_free(struct cx18_stream *s)
{
	struct cx18_buffer *buf;

	/* move all buffers to q_free */
	cx18_flush_queues(s);

	/* empty q_free */
	while ((buf = cx18_dequeue(s, &s->q_free))) {
		pci_unmap_single(s->cx->pci_dev, buf->dma_handle,
				s->buf_size, s->dma);
		kfree(buf->buf);
		kfree(buf);
	}
}
Commit	Line	Data
1c1e45d1 HV	1	/*
	2	* cx18 buffer queues
	3	*
	4	* Derived from ivtv-queue.c
	5	*
	6	* Copyright (C) 2007 Hans Verkuil <hverkuil@xs4all.nl>
1ed9dcc8	7	* Copyright (C) 2008 Andy Walls <awalls@radix.net>
1c1e45d1 HV	8	*
	9	* This program is free software; you can redistribute it and/or modify
	10	* it under the terms of the GNU General Public License as published by
	11	* the Free Software Foundation; either version 2 of the License, or
	12	* (at your option) any later version.
	13	*
	14	* This program is distributed in the hope that it will be useful,
	15	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	16	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	17	* GNU General Public License for more details.
	18	*
	19	* You should have received a copy of the GNU General Public License
	20	* along with this program; if not, write to the Free Software
	21	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
	22	* 02111-1307 USA
	23	*/
	24
	25	#include "cx18-driver.h"
1c1e45d1	26	#include "cx18-queue.h"
21a278b8	27	#include "cx18-streams.h"
1c1e45d1 HV	28	#include "cx18-scb.h"
1c1e45d1 HV	29
1c1e45d1 HV	30	void cx18_buf_swap(struct cx18_buffer *buf)
	31	{
	32	int i;
	33
	34	for (i = 0; i < buf->bytesused; i += 4)
	35	swab32s((u32 *)(buf->buf + i));
	36	}
	37
	38	void cx18_queue_init(struct cx18_queue *q)
	39	{
	40	INIT_LIST_HEAD(&q->list);
b04bce47	41	atomic_set(&q->buffers, 0);
1c1e45d1 HV	42	q->bytesused = 0;
	43	}
	44
66c2a6b0 AW	45	struct cx18_queue _cx18_enqueue(struct cx18_stream s, struct cx18_buffer *buf,
66c2a6b0 AW	46	struct cx18_queue *q, int to_front)
1c1e45d1	47	{
66c2a6b0 AW	48	/* clear the buffer if it is not to be enqueued to the full queue */
66c2a6b0 AW	49	if (q != &s->q_full) {
1c1e45d1 HV	50	buf->bytesused = 0;
	51	buf->readpos = 0;
	52	buf->b_flags = 0;
bca11a57	53	buf->skipped = 0;
1c1e45d1	54	}
66c2a6b0	55
0ef02892 AW	56	/* q_busy is restricted to a max buffer count imposed by firmware */
	57	if (q == &s->q_busy &&
	58	atomic_read(&q->buffers) >= CX18_MAX_FW_MDLS_PER_STREAM)
66c2a6b0 AW	59	q = &s->q_free;
66c2a6b0 AW	60
40c5520f AW	61	spin_lock(&q->lock);
40c5520f AW	62
b80e1074 AW	63	if (to_front)
	64	list_add(&buf->list, &q->list); /* LIFO */
	65	else
	66	list_add_tail(&buf->list, &q->list); /* FIFO */
1c1e45d1	67	q->bytesused += buf->bytesused - buf->readpos;
66c2a6b0 AW	68	atomic_inc(&q->buffers);
66c2a6b0 AW	69
40c5520f	70	spin_unlock(&q->lock);
66c2a6b0	71	return q;
1c1e45d1 HV	72	}
	73
	74	struct cx18_buffer cx18_dequeue(struct cx18_stream s, struct cx18_queue *q)
	75	{
	76	struct cx18_buffer *buf = NULL;
1c1e45d1	77
40c5520f	78	spin_lock(&q->lock);
1c1e45d1	79	if (!list_empty(&q->list)) {
f6b181ac AW	80	buf = list_first_entry(&q->list, struct cx18_buffer, list);
f6b181ac AW	81	list_del_init(&buf->list);
1c1e45d1	82	q->bytesused -= buf->bytesused - buf->readpos;
bca11a57	83	buf->skipped = 0;
66c2a6b0	84	atomic_dec(&q->buffers);
1c1e45d1	85	}
40c5520f	86	spin_unlock(&q->lock);
1c1e45d1 HV	87	return buf;
	88	}
	89
ee2d64f5	90	struct cx18_buffer cx18_queue_get_buf(struct cx18_stream s, u32 id,
1c1e45d1 HV	91	u32 bytesused)
	92	{
	93	struct cx18 *cx = s->cx;
bca11a57	94	struct cx18_buffer *buf;
f6b181ac	95	struct cx18_buffer *tmp;
bca11a57	96	struct cx18_buffer *ret = NULL;
40c5520f AW	97	LIST_HEAD(sweep_up);
	98
	99	/*
	100	* We don't have to acquire multiple q locks here, because we are
	101	* serialized by the single threaded work handler.
	102	* Buffers from the firmware will thus remain in order as
	103	* they are moved from q_busy to q_full or to the dvb ring buffer.
	104	*/
	105	spin_lock(&s->q_busy.lock);
f6b181ac	106	list_for_each_entry_safe(buf, tmp, &s->q_busy.list, list) {
40c5520f AW	107	/*
	108	* We should find what the firmware told us is done,
	109	* right at the front of the queue. If we don't, we likely have
	110	* missed a buffer done message from the firmware.
	111	* Once we skip a buffer repeatedly, relative to the size of
	112	* q_busy, we have high confidence we've missed it.
	113	*/
ee2d64f5	114	if (buf->id != id) {
bca11a57	115	buf->skipped++;
66c2a6b0	116	if (buf->skipped >= atomic_read(&s->q_busy.buffers)-1) {
bca11a57	117	/* buffer must have fallen out of rotation */
bca11a57 AW	118	CX18_WARN("Skipped %s, buffer %d, %d "
	119	"times - it must have dropped out of "
	120	"rotation\n", s->name, buf->id,
	121	buf->skipped);
40c5520f AW	122	/* Sweep it up to put it back into rotation */
40c5520f AW	123	list_move_tail(&buf->list, &sweep_up);
66c2a6b0	124	atomic_dec(&s->q_busy.buffers);
bca11a57	125	}
1c1e45d1	126	continue;
ee2d64f5	127	}
40c5520f AW	128	/*
	129	* We pull the desired buffer off of the queue here. Something
	130	* will have to put it back on a queue later.
	131	*/
	132	list_del_init(&buf->list);
66c2a6b0	133	atomic_dec(&s->q_busy.buffers);
bca11a57 AW	134	ret = buf;
bca11a57 AW	135	break;
1c1e45d1	136	}
40c5520f AW	137	spin_unlock(&s->q_busy.lock);
	138
	139	/*
	140	* We found the buffer for which we were looking. Get it ready for
	141	* the caller to put on q_full or in the dvb ring buffer.
	142	*/
	143	if (ret != NULL) {
	144	ret->bytesused = bytesused;
	145	ret->skipped = 0;
	146	/* readpos and b_flags were 0'ed when the buf went on q_busy */
	147	cx18_buf_sync_for_cpu(s, ret);
	148	if (s->type != CX18_ENC_STREAM_TYPE_TS)
	149	set_bit(CX18_F_B_NEED_BUF_SWAP, &ret->b_flags);
	150	}
	151
	152	/* Put any buffers the firmware is ignoring back into normal rotation */
	153	list_for_each_entry_safe(buf, tmp, &sweep_up, list) {
	154	list_del_init(&buf->list);
	155	cx18_enqueue(s, buf, &s->q_free);
	156	}
bca11a57	157	return ret;
1c1e45d1 HV	158	}
1c1e45d1 HV	159
6c9de528 AW	160	/* Move all buffers of a queue to q_free, while flushing the buffers */
6c9de528 AW	161	static void cx18_queue_flush(struct cx18_stream s, struct cx18_queue q)
1c1e45d1	162	{
6c9de528	163	struct cx18_buffer *buf;
1c1e45d1	164
6c9de528 AW	165	if (q == &s->q_free)
6c9de528 AW	166	return;
1c1e45d1	167
40c5520f	168	spin_lock(&q->lock);
6c9de528	169	while (!list_empty(&q->list)) {
f6b181ac AW	170	buf = list_first_entry(&q->list, struct cx18_buffer, list);
f6b181ac AW	171	list_move_tail(&buf->list, &s->q_free.list);
bca11a57	172	buf->bytesused = buf->readpos = buf->b_flags = buf->skipped = 0;
b04bce47	173	atomic_inc(&s->q_free.buffers);
1c1e45d1	174	}
6c9de528	175	cx18_queue_init(q);
40c5520f	176	spin_unlock(&q->lock);
1c1e45d1 HV	177	}
	178
	179	void cx18_flush_queues(struct cx18_stream *s)
	180	{
66c2a6b0	181	cx18_queue_flush(s, &s->q_busy);
6c9de528	182	cx18_queue_flush(s, &s->q_full);
1c1e45d1 HV	183	}
	184
	185	int cx18_stream_alloc(struct cx18_stream *s)
	186	{
	187	struct cx18 *cx = s->cx;
	188	int i;
	189
	190	if (s->buffers == 0)
	191	return 0;
	192
	193	CX18_DEBUG_INFO("Allocate %s stream: %d x %d buffers (%dkB total)\n",
	194	s->name, s->buffers, s->buf_size,
	195	s->buffers * s->buf_size / 1024);
	196
c6eb8eaf HV	197	if (((char __iomem *)&cx->scb->cpu_mdl[cx->mdl_offset + s->buffers] -
	198	(char __iomem *)cx->scb) > SCB_RESERVED_SIZE) {
	199	unsigned bufsz = (((char __iomem *)cx->scb) + SCB_RESERVED_SIZE -
	200	((char __iomem *)cx->scb->cpu_mdl));
1c1e45d1 HV	201
	202	CX18_ERR("Too many buffers, cannot fit in SCB area\n");
	203	CX18_ERR("Max buffers = %zd\n",
	204	bufsz / sizeof(struct cx18_mdl));
	205	return -ENOMEM;
	206	}
	207
	208	s->mdl_offset = cx->mdl_offset;
	209
	210	/* allocate stream buffers. Initially all buffers are in q_free. */
	211	for (i = 0; i < s->buffers; i++) {
3f98387e HV	212	struct cx18_buffer *buf = kzalloc(sizeof(struct cx18_buffer),
3f98387e HV	213	GFP_KERNEL\|__GFP_NOWARN);
1c1e45d1 HV	214
	215	if (buf == NULL)
	216	break;
3f98387e	217	buf->buf = kmalloc(s->buf_size, GFP_KERNEL\|__GFP_NOWARN);
1c1e45d1 HV	218	if (buf->buf == NULL) {
	219	kfree(buf);
	220	break;
	221	}
	222	buf->id = cx->buffer_id++;
	223	INIT_LIST_HEAD(&buf->list);
3d05913d	224	buf->dma_handle = pci_map_single(s->cx->pci_dev,
1c1e45d1 HV	225	buf->buf, s->buf_size, s->dma);
	226	cx18_buf_sync_for_cpu(s, buf);
	227	cx18_enqueue(s, buf, &s->q_free);
	228	}
	229	if (i == s->buffers) {
	230	cx->mdl_offset += s->buffers;
	231	return 0;
	232	}
	233	CX18_ERR("Couldn't allocate buffers for %s stream\n", s->name);
	234	cx18_stream_free(s);
	235	return -ENOMEM;
	236	}
	237
	238	void cx18_stream_free(struct cx18_stream *s)
	239	{
	240	struct cx18_buffer *buf;
	241
	242	/* move all buffers to q_free */
	243	cx18_flush_queues(s);
	244
	245	/* empty q_free */
	246	while ((buf = cx18_dequeue(s, &s->q_free))) {
3d05913d	247	pci_unmap_single(s->cx->pci_dev, buf->dma_handle,
1c1e45d1 HV	248	s->buf_size, s->dma);
	249	kfree(buf->buf);
	250	kfree(buf);
	251	}
	252	}