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32x: pwm pop reduction hacks

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This commit is contained in:
notaz 2013-08-18 19:32:56 +03:00
parent 419973a6d6
commit 8ce9c3a782
2 changed files with 42 additions and 18 deletions
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55
pico/32x/pwm.c
View file

@ -12,6 +12,7 @@ static int pwm_mult;
static int pwm_ptr;
static int pwm_irq_reload;
static int pwm_doing_fifo;
static int pwm_silent;
void p32x_pwm_ctl_changed(void)
{
@ -20,6 +21,11 @@ void p32x_pwm_ctl_changed(void)
cycles = (cycles - 1) & 0x0fff;
pwm_cycles = cycles;
// supposedly we should stop FIFO when xMd is 0,
// but mars test disagrees
pwm_mult = 0;
if ((control & 0x0f) != 0)
pwm_mult = 0x10000 / cycles;
pwm_irq_reload = (control & 0x0f00) >> 8;
@ -40,6 +46,15 @@ static void do_pwm_irq(SH2 *sh2, unsigned int m68k_cycles)
}
}
static int convert_sample(unsigned int v)
{
if (v == 0)
return 0;
if (v > pwm_cycles)
v = pwm_cycles;
return ((int)v - pwm_cycles / 2) * pwm_mult;
}
#define consume_fifo(sh2, m68k_cycles) { \
int cycles_diff = ((m68k_cycles) * 3) - Pico32x.pwm_cycle_p; \
if (cycles_diff >= pwm_cycles) \
@ -49,6 +64,11 @@ 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)
{
struct Pico32xMem *mem = Pico32xMem;
unsigned short *fifo_l = mem->pwm_fifo[0];
unsigned short *fifo_r = mem->pwm_fifo[1];
int sum = 0;
if (pwm_cycles == 0 || pwm_doing_fifo)
return;
@ -59,30 +79,29 @@ static void consume_fifo_do(SH2 *sh2, unsigned int m68k_cycles,
// this is for recursion from dreq1 writes
pwm_doing_fifo = 1;
while (sh2_cycles_diff >= pwm_cycles) {
struct Pico32xMem *mem = Pico32xMem;
short *fifo_l = mem->pwm_fifo[0];
short *fifo_r = mem->pwm_fifo[1];
for (; sh2_cycles_diff >= pwm_cycles; sh2_cycles_diff -= pwm_cycles)
{
if (Pico32x.pwm_p[0] > 0) {
fifo_l[0] = fifo_l[1];
fifo_l[1] = fifo_l[2];
fifo_l[2] = fifo_l[3];
Pico32x.pwm_p[0]--;
mem->pwm_current[0] = convert_sample(fifo_l[0]);
sum += mem->pwm_current[0];
}
if (Pico32x.pwm_p[1] > 0) {
fifo_r[0] = fifo_r[1];
fifo_r[1] = fifo_r[2];
fifo_r[2] = fifo_r[3];
Pico32x.pwm_p[1]--;
mem->pwm_current[1] = convert_sample(fifo_r[0]);
sum += mem->pwm_current[1];
}
mem->pwm[pwm_ptr * 2 ] = fifo_l[0];
mem->pwm[pwm_ptr * 2 + 1] = fifo_r[0];
mem->pwm[pwm_ptr * 2 ] = mem->pwm_current[0];
mem->pwm[pwm_ptr * 2 + 1] = mem->pwm_current[1];
pwm_ptr = (pwm_ptr + 1) & (PWM_BUFF_LEN - 1);
sh2_cycles_diff -= pwm_cycles;
if (--Pico32x.pwm_irq_cnt == 0) {
Pico32x.pwm_irq_cnt = pwm_irq_reload;
do_pwm_irq(sh2, m68k_cycles);
@ -90,6 +109,8 @@ static void consume_fifo_do(SH2 *sh2, unsigned int m68k_cycles,
}
Pico32x.pwm_cycle_p = m68k_cycles * 3 - sh2_cycles_diff;
pwm_doing_fifo = 0;
if (sum != 0)
pwm_silent = 0;
}
static int p32x_pwm_schedule_(SH2 *sh2, unsigned int m68k_now)
@ -182,8 +203,9 @@ void p32x_pwm_write16(unsigned int a, unsigned int d,
a &= 0x0e;
if (a == 0) { // control
// supposedly we should stop FIFO when xMd is 0,
// but mars test disagrees
// avoiding pops..
if ((Pico32x.regs[0x30 / 2] & 0x0f) == 0)
Pico32xMem->pwm_fifo[0][0] = Pico32xMem->pwm_fifo[1][0] = 0;
Pico32x.regs[0x30 / 2] = d;
p32x_pwm_ctl_changed();
Pico32x.pwm_irq_cnt = pwm_irq_reload; // ?
@ -194,12 +216,9 @@ void p32x_pwm_write16(unsigned int a, unsigned int d,
}
else if (a <= 8) {
d = (d - 1) & 0x0fff;
if (d > pwm_cycles)
d = pwm_cycles;
d = (d - pwm_cycles / 2) * pwm_mult;
if (a == 4 || a == 8) { // L ch or MONO
short *fifo = Pico32xMem->pwm_fifo[0];
unsigned short *fifo = Pico32xMem->pwm_fifo[0];
if (Pico32x.pwm_p[0] < 3)
Pico32x.pwm_p[0]++;
else {
@ -209,7 +228,7 @@ void p32x_pwm_write16(unsigned int a, unsigned int d,
fifo[Pico32x.pwm_p[0]] = d;
}
if (a == 6 || a == 8) { // R ch or MONO
short *fifo = Pico32xMem->pwm_fifo[1];
unsigned short *fifo = Pico32xMem->pwm_fifo[1];
if (Pico32x.pwm_p[1] < 3)
Pico32x.pwm_p[1]++;
else {
@ -233,6 +252,8 @@ void p32x_pwm_update(int *buf32, int length, int stereo)
xmd = Pico32x.regs[0x30 / 2] & 0x0f;
if (xmd == 0 || xmd == 0x06 || xmd == 0x09 || xmd == 0x0f)
goto out; // invalid?
if (pwm_silent)
return;
step = (pwm_ptr << 16) / length;
pwmb = Pico32xMem->pwm;
@ -294,6 +315,8 @@ void p32x_pwm_update(int *buf32, int length, int stereo)
out:
pwm_ptr = 0;
pwm_silent = Pico32xMem->pwm_current[0] == 0
&& Pico32xMem->pwm_current[1] == 0;
}
void p32x_pwm_state_loaded(void)

3
pico/pico_int.h
View file

@ -548,7 +548,8 @@ struct Pico32xMem
unsigned short pal[0x100];
unsigned short pal_native[0x100]; // converted to native (for renderer)
signed short pwm[2*PWM_BUFF_LEN]; // PWM buffer for current frame
signed short pwm_fifo[2][4]; // [0] - current, others - fifo entries
signed short pwm_current[2]; // current converted samples
unsigned short pwm_fifo[2][4]; // [0] - current raw, others - fifo entries
};
// area.c