aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/media/pci/cx18/cx18-queue.c
blob: 2a247d264b87740f6af9bb23ee411a799beb1020 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
/*
 *  cx18 buffer queues
 *
 *  Derived from ivtv-queue.c
 *
 *  Copyright (C) 2007  Hans Verkuil <hverkuil@xs4all.nl>
 *  Copyright (C) 2008  Andy Walls <awalls@md.metrocast.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"
#include "cx18-io.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_mdl_swap(struct cx18_mdl *mdl)
{
	struct cx18_buffer *buf;

	list_for_each_entry(buf, &mdl->buf_list, list) {
		if (buf->bytesused == 0)
			break;
		cx18_buf_swap(buf);
	}
}

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

struct cx18_queue *_cx18_enqueue(struct cx18_stream *s, struct cx18_mdl *mdl,
				 struct cx18_queue *q, int to_front)
{
	/* clear the mdl if it is not to be enqueued to the full queue */
	if (q != &s->q_full) {
		mdl->bytesused = 0;
		mdl->readpos = 0;
		mdl->m_flags = 0;
		mdl->skipped = 0;
		mdl->curr_buf = NULL;
	}

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

	spin_lock(&q->lock);

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

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

struct cx18_mdl *cx18_dequeue(struct cx18_stream *s, struct cx18_queue *q)
{
	struct cx18_mdl *mdl = NULL;

	spin_lock(&q->lock);
	if (!list_empty(&q->list)) {
		mdl = list_first_entry(&q->list, struct cx18_mdl, list);
		list_del_init(&mdl->list);
		q->bytesused -= mdl->bytesused - mdl->readpos;
		mdl->skipped = 0;
		atomic_dec(&q->depth);
	}
	spin_unlock(&q->lock);
	return mdl;
}

static void _cx18_mdl_update_bufs_for_cpu(struct cx18_stream *s,
					  struct cx18_mdl *mdl)
{
	struct cx18_buffer *buf;
	u32 buf_size = s->buf_size;
	u32 bytesused = mdl->bytesused;

	list_for_each_entry(buf, &mdl->buf_list, list) {
		buf->readpos = 0;
		if (bytesused >= buf_size) {
			buf->bytesused = buf_size;
			bytesused -= buf_size;
		} else {
			buf->bytesused = bytesused;
			bytesused = 0;
		}
		cx18_buf_sync_for_cpu(s, buf);
	}
}

static inline void cx18_mdl_update_bufs_for_cpu(struct cx18_stream *s,
						struct cx18_mdl *mdl)
{
	struct cx18_buffer *buf;

	if (list_is_singular(&mdl->buf_list)) {
		buf = list_first_entry(&mdl->buf_list, struct cx18_buffer,
				       list);
		buf->bytesused = mdl->bytesused;
		buf->readpos = 0;
		cx18_buf_sync_for_cpu(s, buf);
	} else {
		_cx18_mdl_update_bufs_for_cpu(s, mdl);
	}
}

struct cx18_mdl *cx18_queue_get_mdl(struct cx18_stream *s, u32 id,
	u32 bytesused)
{
	struct cx18 *cx = s->cx;
	struct cx18_mdl *mdl;
	struct cx18_mdl *tmp;
	struct cx18_mdl *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.
	 * MDLs 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(mdl, 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 an mdl done message from the firmware.
		 * Once we skip an mdl repeatedly, relative to the size of
		 * q_busy, we have high confidence we've missed it.
		 */
		if (mdl->id != id) {
			mdl->skipped++;
			if (mdl->skipped >= atomic_read(&s->q_busy.depth)-1) {
				/* mdl must have fallen out of rotation */
				CX18_WARN("Skipped %s, MDL %d, %d "
					  "times - it must have dropped out of "
					  "rotation\n", s->name, mdl->id,
					  mdl->skipped);
				/* Sweep it up to put it back into rotation */
				list_move_tail(&mdl->list, &sweep_up);
				atomic_dec(&s->q_busy.depth);
			}
			continue;
		}
		/*
		 * We pull the desired mdl off of the queue here.  Something
		 * will have to put it back on a queue later.
		 */
		list_del_init(&mdl->list);
		atomic_dec(&s->q_busy.depth);
		ret = mdl;
		break;
	}
	spin_unlock(&s->q_busy.lock);

	/*
	 * We found the mdl 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;
		/* 0'ed readpos, m_flags & curr_buf when mdl went on q_busy */
		cx18_mdl_update_bufs_for_cpu(s, ret);
		if (s->type != CX18_ENC_STREAM_TYPE_TS)
			set_bit(CX18_F_M_NEED_SWAP, &ret->m_flags);
	}

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

/* Move all mdls of a queue, while flushing the mdl */
static void cx18_queue_flush(struct cx18_stream *s,
			     struct cx18_queue *q_src, struct cx18_queue *q_dst)
{
	struct cx18_mdl *mdl;

	/* It only makes sense to flush to q_free or q_idle */
	if (q_src == q_dst || q_dst == &s->q_full || q_dst == &s->q_busy)
		return;

	spin_lock(&q_src->lock);
	spin_lock(&q_dst->lock);
	while (!list_empty(&q_src->list)) {
		mdl = list_first_entry(&q_src->list, struct cx18_mdl, list);
		list_move_tail(&mdl->list, &q_dst->list);
		mdl->bytesused = 0;
		mdl->readpos = 0;
		mdl->m_flags = 0;
		mdl->skipped = 0;
		mdl->curr_buf = NULL;
		atomic_inc(&q_dst->depth);
	}
	cx18_queue_init(q_src);
	spin_unlock(&q_src->lock);
	spin_unlock(&q_dst->lock);
}

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

/*
 * Note, s->buf_pool is not protected by a lock,
 * the stream better not have *anything* going on when calling this
 */
void cx18_unload_queues(struct cx18_stream *s)
{
	struct cx18_queue *q_idle = &s->q_idle;
	struct cx18_mdl *mdl;
	struct cx18_buffer *buf;

	/* Move all MDLS to q_idle */
	cx18_queue_flush(s, &s->q_busy, q_idle);
	cx18_queue_flush(s, &s->q_full, q_idle);
	cx18_queue_flush(s, &s->q_free, q_idle);

	/* Reset MDL id's and move all buffers back to the stream's buf_pool */
	spin_lock(&q_idle->lock);
	list_for_each_entry(mdl, &q_idle->list, list) {
		while (!list_empty(&mdl->buf_list)) {
			buf = list_first_entry(&mdl->buf_list,
					       struct cx18_buffer, list);
			list_move_tail(&buf->list, &s->buf_pool);
			buf->bytesused = 0;
			buf->readpos = 0;
		}
		mdl->id = s->mdl_base_idx; /* reset id to a "safe" value */
		/* all other mdl fields were cleared by cx18_queue_flush() */
	}
	spin_unlock(&q_idle->lock);
}

/*
 * Note, s->buf_pool is not protected by a lock,
 * the stream better not have *anything* going on when calling this
 */
void cx18_load_queues(struct cx18_stream *s)
{
	struct cx18 *cx = s->cx;
	struct cx18_mdl *mdl;
	struct cx18_buffer *buf;
	int mdl_id;
	int i;
	u32 partial_buf_size;

	/*
	 * Attach buffers to MDLs, give the MDLs ids, and add MDLs to q_free
	 * Excess MDLs are left on q_idle
	 * Excess buffers are left in buf_pool and/or on an MDL in q_idle
	 */
	mdl_id = s->mdl_base_idx;
	for (mdl = cx18_dequeue(s, &s->q_idle), i = s->bufs_per_mdl;
	     mdl != NULL && i == s->bufs_per_mdl;
	     mdl = cx18_dequeue(s, &s->q_idle)) {

		mdl->id = mdl_id;

		for (i = 0; i < s->bufs_per_mdl; i++) {
			if (list_empty(&s->buf_pool))
				break;

			buf = list_first_entry(&s->buf_pool, struct cx18_buffer,
					       list);
			list_move_tail(&buf->list, &mdl->buf_list);

			/* update the firmware's MDL array with this buffer */
			cx18_writel(cx, buf->dma_handle,
				    &cx->scb->cpu_mdl[mdl_id + i].paddr);
			cx18_writel(cx, s->buf_size,
				    &cx->scb->cpu_mdl[mdl_id + i].length);
		}

		if (i == s->bufs_per_mdl) {
			/*
			 * The encoder doesn't honor s->mdl_size.  So in the
			 * case of a non-integral number of buffers to meet
			 * mdl_size, we lie about the size of the last buffer
			 * in the MDL to get the encoder to really only send
			 * us mdl_size bytes per MDL transfer.
			 */
			partial_buf_size = s->mdl_size % s->buf_size;
			if (partial_buf_size) {
				cx18_writel(cx, partial_buf_size,
				      &cx->scb->cpu_mdl[mdl_id + i - 1].length);
			}
			cx18_enqueue(s, mdl, &s->q_free);
		} else {
			/* Not enough buffers for this MDL; we won't use it */
			cx18_push(s, mdl, &s->q_idle);
		}
		mdl_id += i;
	}
}

void _cx18_mdl_sync_for_device(struct cx18_stream *s, struct cx18_mdl *mdl)
{
	int dma = s->dma;
	u32 buf_size = s->buf_size;
	struct pci_dev *pci_dev = s->cx->pci_dev;
	struct cx18_buffer *buf;

	list_for_each_entry(buf, &mdl->buf_list, list)
		pci_dma_sync_single_for_device(pci_dev, buf->dma_handle,
					       buf_size, dma);
}

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 "
			"(%d.%02d kB total)\n",
		s->name, s->buffers, s->buf_size,
		s->buffers * s->buf_size / 1024,
		(s->buffers * s->buf_size * 100 / 1024) % 100);

	if (((char __iomem *)&cx->scb->cpu_mdl[cx->free_mdl_idx + 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 = %zu\n",
			bufsz / sizeof(struct cx18_mdl_ent));
		return -ENOMEM;
	}

	s->mdl_base_idx = cx->free_mdl_idx;

	/* allocate stream buffers and MDLs */
	for (i = 0; i < s->buffers; i++) {
		struct cx18_mdl *mdl;
		struct cx18_buffer *buf;

		/* 1 MDL per buffer to handle the worst & also default case */
		mdl = kzalloc(sizeof(struct cx18_mdl), GFP_KERNEL|__GFP_NOWARN);
		if (mdl == NULL)
			break;

		buf = kzalloc(sizeof(struct cx18_buffer),
				GFP_KERNEL|__GFP_NOWARN);
		if (buf == NULL) {
			kfree(mdl);
			break;
		}

		buf->buf = kmalloc(s->buf_size, GFP_KERNEL|__GFP_NOWARN);
		if (buf->buf == NULL) {
			kfree(mdl);
			kfree(buf);
			break;
		}

		INIT_LIST_HEAD(&mdl->list);
		INIT_LIST_HEAD(&mdl->buf_list);
		mdl->id = s->mdl_base_idx; /* a somewhat safe value */
		cx18_enqueue(s, mdl, &s->q_idle);

		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);
		list_add_tail(&buf->list, &s->buf_pool);
	}
	if (i == s->buffers) {
		cx->free_mdl_idx += 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_mdl *mdl;
	struct cx18_buffer *buf;
	struct cx18 *cx = s->cx;

	CX18_DEBUG_INFO("Deallocating buffers for %s stream\n", s->name);

	/* move all buffers to buf_pool and all MDLs to q_idle */
	cx18_unload_queues(s);

	/* empty q_idle */
	while ((mdl = cx18_dequeue(s, &s->q_idle)))
		kfree(mdl);

	/* empty buf_pool */
	while (!list_empty(&s->buf_pool)) {
		buf = list_first_entry(&s->buf_pool, struct cx18_buffer, list);
		list_del_init(&buf->list);

		pci_unmap_single(s->cx->pci_dev, buf->dma_handle,
				s->buf_size, s->dma);
		kfree(buf->buf);
		kfree(buf);
	}
}

Privacy Policy