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32x: improve pwm a bit more

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This commit is contained in:
notaz 2013-08-15 21:51:27 +03:00
parent 1ac97cbbf2
commit 8ad1d2adf2
1 changed files with 32 additions and 22 deletions
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54
pico/32x/pwm.c
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@ -11,6 +11,7 @@ static int pwm_cycles;
static int pwm_mult;
static int pwm_ptr;
static int pwm_irq_reload;
static int pwm_doing_fifo;
void p32x_pwm_ctl_changed(void)
{
@ -49,21 +50,15 @@ static void do_pwm_irq(SH2 *sh2, unsigned int m68k_cycles)
static void consume_fifo_do(SH2 *sh2, unsigned int m68k_cycles,
int sh2_cycles_diff)
{
int do_irq = 0;
if (pwm_cycles == 0)
if (pwm_cycles == 0 || pwm_doing_fifo)
return;
elprintf(EL_PWM, "pwm: %u: consume %d/%d, %d,%d ptr %d",
m68k_cycles, sh2_cycles_diff, sh2_cycles_diff / pwm_cycles,
Pico32x.pwm_p[0], Pico32x.pwm_p[1], pwm_ptr);
if (sh2_cycles_diff >= pwm_cycles * 17) {
// silence/skip
Pico32x.pwm_cycle_p = m68k_cycles * 3;
Pico32x.pwm_p[0] = Pico32x.pwm_p[1] = 0;
return;
}
// this is for recursion from dreq1 writes
pwm_doing_fifo = 1;
while (sh2_cycles_diff >= pwm_cycles) {
struct Pico32xMem *mem = Pico32xMem;
@ -91,15 +86,11 @@ static void consume_fifo_do(SH2 *sh2, unsigned int m68k_cycles,
if (--Pico32x.pwm_irq_cnt == 0) {
Pico32x.pwm_irq_cnt = pwm_irq_reload;
// irq also does dreq1, so call it after cycle update
do_irq = 1;
break;
do_pwm_irq(sh2, m68k_cycles);
}
}
Pico32x.pwm_cycle_p = m68k_cycles * 3 - sh2_cycles_diff;
if (do_irq)
do_pwm_irq(sh2, m68k_cycles);
pwm_doing_fifo = 0;
}
static int p32x_pwm_schedule_(SH2 *sh2, unsigned int m68k_now)
@ -234,16 +225,29 @@ void p32x_pwm_update(int *buf32, int length, int stereo)
int p = 0;
int xmd;
xmd = Pico32x.regs[0x30 / 2] & 0x0f;
if ((xmd != 0x05 && xmd != 0x0a) || pwm_ptr <= 16)
goto out;
consume_fifo(NULL, SekCyclesDoneT2());
step = (pwm_ptr << 16) / length; // FIXME: division..
xmd = Pico32x.regs[0x30 / 2] & 0x0f;
if (xmd == 0 || xmd == 0x06 || xmd == 0x09 || xmd == 0x0f)
goto out; // invalid?
step = (pwm_ptr << 16) / length;
pwmb = Pico32xMem->pwm;
if (stereo)
{
if (xmd == 0x0a) {
if (xmd == 0x05) {
// normal
while (length-- > 0) {
*buf32++ += pwmb[0];
*buf32++ += pwmb[1];
p += step;
pwmb += (p >> 16) * 2;
p &= 0xffff;
}
}
else if (xmd == 0x0a) {
// channel swap
while (length-- > 0) {
*buf32++ += pwmb[1];
@ -255,18 +259,24 @@ void p32x_pwm_update(int *buf32, int length, int stereo)
}
}
else {
// mono - LMD, RMD specify dst
if (xmd & 0x06) // src is R
pwmb++;
if (xmd & 0x0c) // dst is R
buf32++;
while (length-- > 0) {
*buf32++ += pwmb[0];
*buf32++ += pwmb[1];
*buf32 += *pwmb;
p += step;
pwmb += (p >> 16) * 2;
p &= 0xffff;
buf32 += 2;
}
}
}
else
{
// mostly unused
while (length-- > 0) {
*buf32++ += pwmb[0];