d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

channel.c:

Browse Source 
(1) Fix DMA alignment, based on bytes per sample.

feeder_rate.c:
	Handle strayed bytes (mostly caused by #1) better.

This DMA alignment issues are extremely hard to reproduce unless
the user happen to have a 32bit capable soundcards (ATI IXP) and
knowledgeable enough to force it to operate under pure 32bit
operations on both record and play directions.
This commit is contained in:
Ariff Abdullah 2006-01-24 01:10:07 +00:00
parent 7f34b521c7
commit 14665331ab
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=154741
2 changed files with 29 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
sys/dev/sound/pcm/channel.c
View File

@ -34,8 +34,11 @@
SND_DECLARE_FILE("$FreeBSD$");
#define MIN_CHUNK_SIZE 256 /* for uiomove etc. */
#if 0
#define DMA_ALIGN_THRESHOLD 4
#define DMA_ALIGN_MASK (~(DMA_ALIGN_THRESHOLD - 1))
#endif
#define DMA_ALIGN_MASK(bps) (~((bps) - 1))
#define CANCHANGE(c) (!(c->flags & CHN_F_TRIGGERED))
@ -1253,7 +1256,10 @@ chn_getptr(struct pcm_channel *c)
#if 1
hwptr &= ~a ; /* Apply channel align mask */
#endif
#if 0
hwptr &= DMA_ALIGN_MASK; /* Apply DMA align mask */
#endif
hwptr &= DMA_ALIGN_MASK(sndbuf_getbps(c->bufhard));
return hwptr;
}

33
sys/dev/sound/pcm/feeder_rate.c
View File

@ -100,6 +100,7 @@ struct feed_rate_info {
uint32_t alpha; /* interpolation distance */
uint32_t pos, bpos; /* current sample / buffer positions */
uint32_t bufsz; /* total buffer size */
uint32_t stray; /* stray bytes */
int32_t scale, roll; /* scale / roll factor */
int16_t *buffer;
uint32_t (*convert)(struct feed_rate_info *, int16_t *, uint32_t);
@ -350,6 +351,7 @@ feed_rate_setup(struct pcm_feeder *f)
info->pos = 2;
info->bpos = 4;
info->alpha = 0;
info->stray = 0;
feed_rate_reset(info);
if (info->src == info->dst) {
/*
@ -710,12 +712,13 @@ feed_rate(struct pcm_feeder *f, struct pcm_channel *c, uint8_t *b,
slot = (((info->gx * (count >> 1)) + info->gy - info->alpha - 1) / info->gy) << 1;
RATE_TEST((slot & 1) == 0, ("%s: Slot count not sample integral (%d)\n",
__func__, slot));
slot &= ~1;
/*
* Optimize buffer feeding aggresively to ensure calculated slot
* can be fitted nicely into available buffer free space, hence
* avoiding multiple feeding.
*/
RATE_TEST(info->stray == 0, ("%s: [1] Stray bytes: %u\n",
__func__,info->stray));
if (info->pos != 2 && info->bpos - info->pos == 2 &&
info->bpos + slot > info->bufsz) {
/*
@ -734,25 +737,31 @@ feed_rate(struct pcm_feeder *f, struct pcm_channel *c, uint8_t *b,
i = 0;
for (;;) {
for (;;) {
fetch = info->bufsz - info->bpos;
fetch = (info->bufsz - info->bpos) << 1;
fetch -= info->stray;
RATE_ASSERT(fetch >= 0,
("%s: [1] Buffer overrun: %d > %d\n",
__func__, info->bpos, info->bufsz));
if (slot < fetch)
fetch = slot;
fetch &= ~1;
if ((slot << 1) < fetch)
fetch = slot << 1;
if (fetch > 0) {
RATE_TEST((fetch & 1) == 0,
("%s: Fetch size not sample integral (%d)\n",
__func__, fetch));
RATE_ASSERT(((info->bpos << 1) - info->stray) >= 0 &&
((info->bpos << 1) - info->stray) < (info->bufsz << 1),
("%s: DANGER - BUFFER OVERRUN! bufsz=%d, pos=%d\n", __func__,
info->bufsz << 1, (info->bpos << 1) - info->stray));
fetch = FEEDER_FEED(f->source, c,
(uint8_t *)(info->buffer + info->bpos),
fetch << 1, source);
(uint8_t *)(info->buffer) + (info->bpos << 1) - info->stray,
fetch, source);
info->stray = 0;
if (fetch == 0)
break;
RATE_TEST((fetch & 3) == 0,
("%s: Fetch size not byte integral (%d)\n",
__func__, fetch));
info->stray += fetch & 3;
RATE_TEST(info->stray == 0,
("%s: Stray bytes detected (%d)\n",
__func__, info->stray));
fetch >>= 1;
fetch &= ~1;
info->bpos += fetch;
@ -790,6 +799,7 @@ feed_rate(struct pcm_feeder *f, struct pcm_channel *c, uint8_t *b,
* to beginning of buffer so next cycle can
* interpolate using it.
*/
RATE_TEST(info->stray == 0, ("%s: [2] Stray bytes: %u\n", __func__, info->stray));
info->buffer[0] = info->buffer[info->pos - 2];
info->buffer[1] = info->buffer[info->pos - 1];
info->bpos = 2;
@ -798,7 +808,10 @@ feed_rate(struct pcm_feeder *f, struct pcm_channel *c, uint8_t *b,
if (i == count)
break;
}
#if 0
RATE_TEST(count == i, ("Expect: %u , Got: %u\n", count << 1, i << 1));
#endif
RATE_TEST(info->stray == 0, ("%s: [3] Stray bytes: %u\n", __func__, info->stray));
return i << 1;
}