xref: /freebsd/sys/dev/sound/pcm/buffer.c (revision b8aa2713423518bc3d708a08b52433096de96e9b) 
1 /*-
2  * Copyright (c) 1999 Cameron Grant <cg@freebsd.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <dev/sound/pcm/sound.h>
28 
29 #include "feeder_if.h"
30 
31 SND_DECLARE_FILE("$FreeBSD$");
32 
33 struct snd_dbuf *
34 sndbuf_create(device_t dev, char *drv, char *desc, struct pcm_channel *channel)
35 {
36 	struct snd_dbuf *b;
37 
38 	b = malloc(sizeof(*b), M_DEVBUF, M_WAITOK | M_ZERO);
39 	snprintf(b->name, SNDBUF_NAMELEN, "%s:%s", drv, desc);
40 	b->dev = dev;
41 	b->channel = channel;
42 
43 	return b;
44 }
45 
46 void
47 sndbuf_destroy(struct snd_dbuf *b)
48 {
49 	free(b, M_DEVBUF);
50 }
51 
52 bus_addr_t
53 sndbuf_getbufaddr(struct snd_dbuf *buf)
54 {
55 	return (buf->buf_addr);
56 }
57 
58 static void
59 sndbuf_setmap(void *arg, bus_dma_segment_t *segs, int nseg, int error)
60 {
61 	struct snd_dbuf *b = (struct snd_dbuf *)arg;
62 
63 	if (bootverbose) {
64 		device_printf(b->dev, "sndbuf_setmap %lx, %lx; ",
65 		    (u_long)segs[0].ds_addr, (u_long)segs[0].ds_len);
66 		printf("%p -> %lx\n", b->buf, (u_long)segs[0].ds_addr);
67 	}
68 	if (error == 0)
69 		b->buf_addr = segs[0].ds_addr;
70 	else
71 		b->buf_addr = 0;
72 }
73 
74 /*
75  * Allocate memory for DMA buffer. If the device does not use DMA transfers,
76  * the driver can call malloc(9) and sndbuf_setup() itself.
77  */
78 
79 int
80 sndbuf_alloc(struct snd_dbuf *b, bus_dma_tag_t dmatag, unsigned int size)
81 {
82 	int ret;
83 
84 	b->dmatag = dmatag;
85 	b->maxsize = size;
86 	b->bufsize = b->maxsize;
87 	b->buf_addr = 0;
88 	if (bus_dmamem_alloc(b->dmatag, (void **)&b->buf, BUS_DMA_NOWAIT,
89 	    &b->dmamap))
90 		return (ENOMEM);
91 	if (bus_dmamap_load(b->dmatag, b->dmamap, b->buf, b->maxsize,
92 	    sndbuf_setmap, b, 0) != 0 || b->buf_addr == 0) {
93 		bus_dmamem_free(b->dmatag, b->buf, b->dmamap);
94 		b->dmamap = NULL;
95 		return (ENOMEM);
96 	}
97 
98 	ret = sndbuf_resize(b, 2, b->maxsize / 2);
99 	if (ret != 0)
100 		sndbuf_free(b);
101 	return (ret);
102 }
103 
104 int
105 sndbuf_setup(struct snd_dbuf *b, void *buf, unsigned int size)
106 {
107 	b->buf = buf;
108 	b->maxsize = size;
109 	b->bufsize = b->maxsize;
110 	return sndbuf_resize(b, 2, b->maxsize / 2);
111 }
112 
113 void
114 sndbuf_free(struct snd_dbuf *b)
115 {
116 	if (b->tmpbuf)
117 		free(b->tmpbuf, M_DEVBUF);
118 	b->tmpbuf = NULL;
119 
120 	if (b->shadbuf)
121 		free(b->shadbuf, M_DEVBUF);
122 	b->shadbuf = NULL;
123 	b->sl = 0;
124 
125 	if (b->dmamap)
126 		bus_dmamap_unload(b->dmatag, b->dmamap);
127 
128 	if (b->dmamap && b->buf)
129 		bus_dmamem_free(b->dmatag, b->buf, b->dmamap);
130 	b->dmamap = NULL;
131 	b->buf = NULL;
132 }
133 
134 int
135 sndbuf_resize(struct snd_dbuf *b, unsigned int blkcnt, unsigned int blksz)
136 {
137 	u_int8_t *tmpbuf, *f2;
138 
139 	chn_lock(b->channel);
140 	if (b->maxsize == 0)
141 		goto out;
142 	if (blkcnt == 0)
143 		blkcnt = b->blkcnt;
144 	if (blksz == 0)
145 		blksz = b->blksz;
146 	if (blkcnt < 2 || blksz < 16 || (blkcnt * blksz > b->maxsize)) {
147 		chn_unlock(b->channel);
148 		return EINVAL;
149 	}
150 	if (blkcnt == b->blkcnt && blksz == b->blksz)
151 		goto out;
152 
153 	chn_unlock(b->channel);
154 	tmpbuf = malloc(blkcnt * blksz, M_DEVBUF, M_NOWAIT);
155 	if (tmpbuf == NULL)
156 		return ENOMEM;
157 	chn_lock(b->channel);
158 	b->blkcnt = blkcnt;
159 	b->blksz = blksz;
160 	b->bufsize = blkcnt * blksz;
161 	f2 =  b->tmpbuf;
162 	b->tmpbuf = tmpbuf;
163 	sndbuf_reset(b);
164 	chn_unlock(b->channel);
165 	free(f2, M_DEVBUF);
166 	return 0;
167 out:
168 	chn_unlock(b->channel);
169 	return 0;
170 }
171 
172 int
173 sndbuf_remalloc(struct snd_dbuf *b, unsigned int blkcnt, unsigned int blksz)
174 {
175         u_int8_t *buf, *tmpbuf, *f1, *f2;
176 	u_int8_t *shadbuf, *f3;
177         unsigned int bufsize;
178 	int ret;
179 
180 	if (blkcnt < 2 || blksz < 16)
181 		return EINVAL;
182 
183 	bufsize = blksz * blkcnt;
184 
185 	chn_unlock(b->channel);
186 	buf = malloc(bufsize, M_DEVBUF, M_WAITOK);
187 	if (buf == NULL) {
188 		ret = ENOMEM;
189 		goto out;
190 	}
191 
192 	tmpbuf = malloc(bufsize, M_DEVBUF, M_WAITOK);
193    	if (tmpbuf == NULL) {
194 		free(buf, M_DEVBUF);
195 		ret = ENOMEM;
196 		goto out;
197 	}
198 
199 	shadbuf = malloc(bufsize, M_DEVBUF, M_WAITOK);
200 	if (shadbuf == NULL) {
201 		free(buf, M_DEVBUF);
202 		free(tmpbuf, M_DEVBUF);
203 		ret = ENOMEM;
204 		goto out;
205 	}
206 
207 	chn_lock(b->channel);
208 
209 	b->blkcnt = blkcnt;
210 	b->blksz = blksz;
211 	b->bufsize = bufsize;
212 	b->maxsize = bufsize;
213 	f1 = b->buf;
214 	f2 = b->tmpbuf;
215 	b->buf = buf;
216 	b->tmpbuf = tmpbuf;
217 	f3 = b->shadbuf;
218 	b->shadbuf = shadbuf;
219 	b->sl = bufsize;
220 
221 	sndbuf_reset(b);
222 
223 	chn_unlock(b->channel);
224       	if (f1)
225 		free(f1, M_DEVBUF);
226       	if (f2)
227 		free(f2, M_DEVBUF);
228 	if (f3)
229 		free(f3, M_DEVBUF);
230 
231 	ret = 0;
232 out:
233 	chn_lock(b->channel);
234 	return ret;
235 }
236 
237 /**
238  * @brief Zero out space in buffer free area
239  *
240  * This function clears a chunk of @c length bytes in the buffer free area
241  * (i.e., where the next write will be placed).
242  *
243  * @param b		buffer context
244  * @param length	number of bytes to blank
245  */
246 void
247 sndbuf_clear(struct snd_dbuf *b, unsigned int length)
248 {
249 	int i;
250 	u_char data, *p;
251 
252 	if (length == 0)
253 		return;
254 	if (length > b->bufsize)
255 		length = b->bufsize;
256 
257 	if (b->fmt & AFMT_SIGNED)
258 		data = 0x00;
259 	else
260 		data = 0x80;
261 
262 	i = sndbuf_getfreeptr(b);
263 	p = sndbuf_getbuf(b);
264 	while (length > 0) {
265 		p[i] = data;
266 		length--;
267 		i++;
268 		if (i >= b->bufsize)
269 			i = 0;
270 	}
271 }
272 
273 /**
274  * @brief Zap buffer contents, resetting "ready area" fields
275  *
276  * @param b	buffer context
277  */
278 void
279 sndbuf_fillsilence(struct snd_dbuf *b)
280 {
281 	int i;
282 	u_char data, *p;
283 
284 	if (b->fmt & AFMT_SIGNED)
285 		data = 0x00;
286 	else
287 		data = 0x80;
288 
289 	i = 0;
290 	p = sndbuf_getbuf(b);
291 	while (i < b->bufsize)
292 		p[i++] = data;
293 	b->rp = 0;
294 	b->rl = b->bufsize;
295 }
296 
297 /**
298  * @brief Reset buffer w/o flushing statistics
299  *
300  * This function just zeroes out buffer contents and sets the "ready length"
301  * to zero.  This was originally to facilitate minimal playback interruption
302  * (i.e., dropped samples) in SNDCTL_DSP_SILENCE/SKIP ioctls.
303  *
304  * @param b	buffer context
305  */
306 void
307 sndbuf_softreset(struct snd_dbuf *b)
308 {
309 	b->rl = 0;
310 	if (b->buf && b->bufsize > 0)
311 		sndbuf_clear(b, b->bufsize);
312 }
313 
314 void
315 sndbuf_reset(struct snd_dbuf *b)
316 {
317 	b->hp = 0;
318 	b->rp = 0;
319 	b->rl = 0;
320 	b->dl = 0;
321 	b->prev_total = 0;
322 	b->total = 0;
323 	b->xrun = 0;
324 	if (b->buf && b->bufsize > 0)
325 		sndbuf_clear(b, b->bufsize);
326 	sndbuf_clearshadow(b);
327 }
328 
329 u_int32_t
330 sndbuf_getfmt(struct snd_dbuf *b)
331 {
332 	return b->fmt;
333 }
334 
335 int
336 sndbuf_setfmt(struct snd_dbuf *b, u_int32_t fmt)
337 {
338 	b->fmt = fmt;
339 	b->bps = 1;
340 	b->bps <<= (b->fmt & AFMT_STEREO)? 1 : 0;
341 	if (b->fmt & AFMT_16BIT)
342 		b->bps <<= 1;
343 	else if (b->fmt & AFMT_24BIT)
344 		b->bps *= 3;
345 	else if (b->fmt & AFMT_32BIT)
346 		b->bps <<= 2;
347 	return 0;
348 }
349 
350 unsigned int
351 sndbuf_getspd(struct snd_dbuf *b)
352 {
353 	return b->spd;
354 }
355 
356 void
357 sndbuf_setspd(struct snd_dbuf *b, unsigned int spd)
358 {
359 	b->spd = spd;
360 }
361 
362 unsigned int
363 sndbuf_getalign(struct snd_dbuf *b)
364 {
365 	static int align[] = {0, 1, 1, 2, 2, 2, 2, 3};
366 
367 	return align[b->bps - 1];
368 }
369 
370 unsigned int
371 sndbuf_getblkcnt(struct snd_dbuf *b)
372 {
373 	return b->blkcnt;
374 }
375 
376 void
377 sndbuf_setblkcnt(struct snd_dbuf *b, unsigned int blkcnt)
378 {
379 	b->blkcnt = blkcnt;
380 }
381 
382 unsigned int
383 sndbuf_getblksz(struct snd_dbuf *b)
384 {
385 	return b->blksz;
386 }
387 
388 void
389 sndbuf_setblksz(struct snd_dbuf *b, unsigned int blksz)
390 {
391 	b->blksz = blksz;
392 }
393 
394 unsigned int
395 sndbuf_getbps(struct snd_dbuf *b)
396 {
397 	return b->bps;
398 }
399 
400 void *
401 sndbuf_getbuf(struct snd_dbuf *b)
402 {
403 	return b->buf;
404 }
405 
406 void *
407 sndbuf_getbufofs(struct snd_dbuf *b, unsigned int ofs)
408 {
409 	KASSERT(ofs < b->bufsize, ("%s: ofs invalid %d", __func__, ofs));
410 
411 	return b->buf + ofs;
412 }
413 
414 unsigned int
415 sndbuf_getsize(struct snd_dbuf *b)
416 {
417 	return b->bufsize;
418 }
419 
420 unsigned int
421 sndbuf_getmaxsize(struct snd_dbuf *b)
422 {
423 	return b->maxsize;
424 }
425 
426 unsigned int
427 sndbuf_runsz(struct snd_dbuf *b)
428 {
429 	return b->dl;
430 }
431 
432 void
433 sndbuf_setrun(struct snd_dbuf *b, int go)
434 {
435 	b->dl = go? b->blksz : 0;
436 }
437 
438 struct selinfo *
439 sndbuf_getsel(struct snd_dbuf *b)
440 {
441 	return &b->sel;
442 }
443 
444 /************************************************************/
445 unsigned int
446 sndbuf_getxrun(struct snd_dbuf *b)
447 {
448 	SNDBUF_LOCKASSERT(b);
449 
450 	return b->xrun;
451 }
452 
453 void
454 sndbuf_setxrun(struct snd_dbuf *b, unsigned int xrun)
455 {
456 	SNDBUF_LOCKASSERT(b);
457 
458 	b->xrun = xrun;
459 }
460 
461 unsigned int
462 sndbuf_gethwptr(struct snd_dbuf *b)
463 {
464 	SNDBUF_LOCKASSERT(b);
465 
466 	return b->hp;
467 }
468 
469 void
470 sndbuf_sethwptr(struct snd_dbuf *b, unsigned int ptr)
471 {
472 	SNDBUF_LOCKASSERT(b);
473 
474 	b->hp = ptr;
475 }
476 
477 unsigned int
478 sndbuf_getready(struct snd_dbuf *b)
479 {
480 	SNDBUF_LOCKASSERT(b);
481 	KASSERT((b->rl >= 0) && (b->rl <= b->bufsize), ("%s: b->rl invalid %d", __func__, b->rl));
482 
483 	return b->rl;
484 }
485 
486 unsigned int
487 sndbuf_getreadyptr(struct snd_dbuf *b)
488 {
489 	SNDBUF_LOCKASSERT(b);
490 	KASSERT((b->rp >= 0) && (b->rp <= b->bufsize), ("%s: b->rp invalid %d", __func__, b->rp));
491 
492 	return b->rp;
493 }
494 
495 unsigned int
496 sndbuf_getfree(struct snd_dbuf *b)
497 {
498 	SNDBUF_LOCKASSERT(b);
499 	KASSERT((b->rl >= 0) && (b->rl <= b->bufsize), ("%s: b->rl invalid %d", __func__, b->rl));
500 
501 	return b->bufsize - b->rl;
502 }
503 
504 unsigned int
505 sndbuf_getfreeptr(struct snd_dbuf *b)
506 {
507 	SNDBUF_LOCKASSERT(b);
508 	KASSERT((b->rp >= 0) && (b->rp <= b->bufsize), ("%s: b->rp invalid %d", __func__, b->rp));
509 	KASSERT((b->rl >= 0) && (b->rl <= b->bufsize), ("%s: b->rl invalid %d", __func__, b->rl));
510 
511 	return (b->rp + b->rl) % b->bufsize;
512 }
513 
514 unsigned int
515 sndbuf_getblocks(struct snd_dbuf *b)
516 {
517 	SNDBUF_LOCKASSERT(b);
518 
519 	return b->total / b->blksz;
520 }
521 
522 unsigned int
523 sndbuf_getprevblocks(struct snd_dbuf *b)
524 {
525 	SNDBUF_LOCKASSERT(b);
526 
527 	return b->prev_total / b->blksz;
528 }
529 
530 unsigned int
531 sndbuf_gettotal(struct snd_dbuf *b)
532 {
533 	SNDBUF_LOCKASSERT(b);
534 
535 	return b->total;
536 }
537 
538 void
539 sndbuf_updateprevtotal(struct snd_dbuf *b)
540 {
541 	SNDBUF_LOCKASSERT(b);
542 
543 	b->prev_total = b->total;
544 }
545 
546 /************************************************************/
547 
548 /**
549  * @brief Acquire buffer space to extend ready area
550  *
551  * This function extends the ready area length by @c count bytes, and may
552  * optionally copy samples from another location stored in @c from.  The
553  * counter @c snd_dbuf::total is also incremented by @c count bytes.
554  *
555  * @param b	audio buffer
556  * @param from	sample source (optional)
557  * @param count	number of bytes to acquire
558  *
559  * @retval 0	Unconditional
560  */
561 int
562 sndbuf_acquire(struct snd_dbuf *b, u_int8_t *from, unsigned int count)
563 {
564 	int l;
565 
566 	KASSERT(count <= sndbuf_getfree(b), ("%s: count %d > free %d", __func__, count, sndbuf_getfree(b)));
567 	KASSERT((b->rl >= 0) && (b->rl <= b->bufsize), ("%s: b->rl invalid %d", __func__, b->rl));
568 	b->total += count;
569 	if (from != NULL) {
570 		while (count > 0) {
571 			l = MIN(count, sndbuf_getsize(b) - sndbuf_getfreeptr(b));
572 			bcopy(from, sndbuf_getbufofs(b, sndbuf_getfreeptr(b)), l);
573 			from += l;
574 			b->rl += l;
575 			count -= l;
576 		}
577 	} else
578 		b->rl += count;
579 	KASSERT((b->rl >= 0) && (b->rl <= b->bufsize), ("%s: b->rl invalid %d, count %d", __func__, b->rl, count));
580 
581 	return 0;
582 }
583 
584 /**
585  * @brief Dispose samples from channel buffer, increasing size of ready area
586  *
587  * This function discards samples from the supplied buffer by advancing the
588  * ready area start pointer and decrementing the ready area length.  If
589  * @c to is not NULL, then the discard samples will be copied to the location
590  * it points to.
591  *
592  * @param b	PCM channel sound buffer
593  * @param to	destination buffer (optional)
594  * @param count	number of bytes to discard
595  *
596  * @returns 0 unconditionally
597  */
598 int
599 sndbuf_dispose(struct snd_dbuf *b, u_int8_t *to, unsigned int count)
600 {
601 	int l;
602 
603 	KASSERT(count <= sndbuf_getready(b), ("%s: count %d > ready %d", __func__, count, sndbuf_getready(b)));
604 	KASSERT((b->rl >= 0) && (b->rl <= b->bufsize), ("%s: b->rl invalid %d", __func__, b->rl));
605 	if (to != NULL) {
606 		while (count > 0) {
607 			l = MIN(count, sndbuf_getsize(b) - sndbuf_getreadyptr(b));
608 			bcopy(sndbuf_getbufofs(b, sndbuf_getreadyptr(b)), to, l);
609 			to += l;
610 			b->rl -= l;
611 			b->rp = (b->rp + l) % b->bufsize;
612 			count -= l;
613 		}
614 	} else {
615 		b->rl -= count;
616 		b->rp = (b->rp + count) % b->bufsize;
617 	}
618 	KASSERT((b->rl >= 0) && (b->rl <= b->bufsize), ("%s: b->rl invalid %d, count %d", __func__, b->rl, count));
619 
620 	return 0;
621 }
622 
623 /* count is number of bytes we want added to destination buffer */
624 int
625 sndbuf_feed(struct snd_dbuf *from, struct snd_dbuf *to, struct pcm_channel *channel, struct pcm_feeder *feeder, unsigned int count)
626 {
627 	KASSERT(count > 0, ("can't feed 0 bytes"));
628 
629 	if (sndbuf_getfree(to) < count)
630 		return EINVAL;
631 
632 	count = FEEDER_FEED(feeder, channel, to->tmpbuf, count, from);
633 	if (count)
634 		sndbuf_acquire(to, to->tmpbuf, count);
635 	/* the root feeder has called sndbuf_dispose(from, , bytes fetched) */
636 
637 	return 0;
638 }
639 
640 /************************************************************/
641 
642 void
643 sndbuf_dump(struct snd_dbuf *b, char *s, u_int32_t what)
644 {
645 	printf("%s: [", s);
646 	if (what & 0x01)
647 		printf(" bufsize: %d, maxsize: %d", b->bufsize, b->maxsize);
648 	if (what & 0x02)
649 		printf(" dl: %d, rp: %d, rl: %d, hp: %d", b->dl, b->rp, b->rl, b->hp);
650 	if (what & 0x04)
651 		printf(" total: %d, prev_total: %d, xrun: %d", b->total, b->prev_total, b->xrun);
652    	if (what & 0x08)
653 		printf(" fmt: 0x%x, spd: %d", b->fmt, b->spd);
654 	if (what & 0x10)
655 		printf(" blksz: %d, blkcnt: %d, flags: 0x%x", b->blksz, b->blkcnt, b->flags);
656 	printf(" ]\n");
657 }
658 
659 /************************************************************/
660 u_int32_t
661 sndbuf_getflags(struct snd_dbuf *b)
662 {
663 	return b->flags;
664 }
665 
666 void
667 sndbuf_setflags(struct snd_dbuf *b, u_int32_t flags, int on)
668 {
669 	b->flags &= ~flags;
670 	if (on)
671 		b->flags |= flags;
672 }
673 
674 /**
675  * @brief Clear the shadow buffer by filling with samples equal to zero.
676  *
677  * @param b buffer to clear
678  */
679 void
680 sndbuf_clearshadow(struct snd_dbuf *b)
681 {
682 	KASSERT(b != NULL, ("b is a null pointer"));
683 	KASSERT(b->sl >= 0, ("illegal shadow length"));
684 
685 	if ((b->shadbuf != NULL) && (b->sl > 0)) {
686 		if (b->fmt & AFMT_SIGNED)
687 			memset(b->shadbuf, 0x00, b->sl);
688 		else
689 			memset(b->shadbuf, 0x80, b->sl);
690 	}
691 }
692 
693 #ifdef OSSV4_EXPERIMENT
694 /**
695  * @brief Return peak value from samples in buffer ready area.
696  *
697  * Peak ranges from 0-32767.  If channel is monaural, most significant 16
698  * bits will be zero.  For now, only expects to work with 1-2 channel
699  * buffers.
700  *
701  * @note  Currently only operates with linear PCM formats.
702  *
703  * @param b buffer to analyze
704  * @param lpeak pointer to store left peak value
705  * @param rpeak pointer to store right peak value
706  */
707 void
708 sndbuf_getpeaks(struct snd_dbuf *b, int *lp, int *rp)
709 {
710 	u_int32_t lpeak, rpeak;
711 
712 	lpeak = 0;
713 	rpeak = 0;
714 
715 	/**
716 	 * @todo fill this in later
717 	 */
718 }
719 #endif
720