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Split arch-dependent codes of dmix

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Split arch-dependent codes of dmix to separate files.
This commit is contained in:
Takashi Iwai 2005-02-08 20:28:29 +00:00
parent c92969845d
commit 22846c486f
5 changed files with 220 additions and 166 deletions
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119
src/pcm/pcm_dmix_generic.c Normal file
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@ -0,0 +1,119 @@
#if defined(__i386__) || defined(__x86_64__)
#define LOCK_PREFIX "lock ; "
#define ARCH_ADD(p,a) \
__asm__ __volatile__(LOCK_PREFIX "addl %1,%0" \
:"=m" (*p) \
:"ir" (a), "m" (*p))
struct __xchg_dummy { unsigned long a[100]; };
#define __xg(x) ((struct __xchg_dummy *)(x))
static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old,
unsigned long new, int size)
{
unsigned long prev;
switch (size) {
case 1:
__asm__ __volatile__(LOCK_PREFIX "cmpxchgb %b1,%2"
: "=a"(prev)
: "q"(new), "m"(*__xg(ptr)), "0"(old)
: "memory");
return prev;
case 2:
__asm__ __volatile__(LOCK_PREFIX "cmpxchgw %w1,%2"
: "=a"(prev)
: "q"(new), "m"(*__xg(ptr)), "0"(old)
: "memory");
return prev;
case 4:
__asm__ __volatile__(LOCK_PREFIX "cmpxchgl %1,%2"
: "=a"(prev)
: "q"(new), "m"(*__xg(ptr)), "0"(old)
: "memory");
return prev;
}
return old;
}
#define ARCH_CMPXCHG(ptr,o,n)\
((__typeof__(*(ptr)))__cmpxchg((ptr),(unsigned long)(o),\
(unsigned long)(n),sizeof(*(ptr))))
#endif
#ifndef ARCH_ADD
#warning Please, define atomic ADD and CMPXCHG for your architecture...
#define ARCH_ADD(p,a) (*(p) += (a))
#define ARCH_CMPXCHG(p,a,b) (*(p)) /* fake */
#endif
static void mix_areas1(unsigned int size,
volatile signed short *dst, signed short *src,
volatile signed int *sum, size_t dst_step,
size_t src_step, size_t sum_step)
{
register signed int sample, old_sample;
src_step /= sizeof(*src);
dst_step /= sizeof(*dst);
sum_step /= sizeof(*sum);
for (;;) {
sample = *src;
old_sample = *sum;
if (ARCH_CMPXCHG(dst, 0, 1) == 0)
sample -= old_sample;
ARCH_ADD(sum, sample);
do {
old_sample = *sum;
if (old_sample > 0x7fff)
sample = 0x7fff;
else if (old_sample < -0x8000)
sample = -0x8000;
else
sample = old_sample;
*dst = sample;
} while (*sum != old_sample);
if (!--size)
return;
src += src_step;
dst += dst_step;
sum += sum_step;
}
}
static void mix_areas2(unsigned int size,
volatile signed int *dst, signed int *src,
volatile signed int *sum, size_t dst_step,
size_t src_step, size_t sum_step)
{
register signed int sample, old_sample;
src_step /= sizeof(*src);
dst_step /= sizeof(*dst);
sum_step /= sizeof(*sum);
for (;;) {
sample = *src / 256;
old_sample = *sum;
if (ARCH_CMPXCHG(dst, 0, 1) == 0)
sample -= old_sample;
ARCH_ADD(sum, sample);
do {
old_sample = *sum;
if (old_sample > 0x7fffff)
sample = 0x7fffffff;
else if (old_sample < -0x800000)
sample = -0x80000000;
else
sample = old_sample * 256;
*dst = sample;
} while (*sum != old_sample);
if (!--size)
return;
src += src_step;
dst += dst_step;
sum += sum_step;
}
}
static void mix_select_callbacks(snd_pcm_direct_t *dmix)
{
dmix->u.dmix.mix_areas1 = mix_areas1;
dmix->u.dmix.mix_areas2 = mix_areas2;
}