mirror of
https://github.com/RaySollium99/picodrive.git
synced 2025-09-05 07:17:45 -04:00
341 lines
8 KiB
C
341 lines
8 KiB
C
/*
|
|
* PicoDrive
|
|
* (C) notaz, 2009,2010,2013
|
|
*
|
|
* This work is licensed under the terms of MAME license.
|
|
* See COPYING file in the top-level directory.
|
|
*/
|
|
#include "../pico_int.h"
|
|
|
|
static struct {
|
|
int cycles;
|
|
int mult;
|
|
int ptr;
|
|
int irq_reload;
|
|
int doing_fifo;
|
|
int silent;
|
|
short current[2];
|
|
} pwm;
|
|
|
|
void p32x_pwm_ctl_changed(void)
|
|
{
|
|
int control = Pico32x.regs[0x30 / 2];
|
|
int cycles = Pico32x.regs[0x32 / 2];
|
|
|
|
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;
|
|
pwm.irq_reload = ((pwm.irq_reload - 1) & 0x0f) + 1;
|
|
|
|
if (Pico32x.pwm_irq_cnt == 0)
|
|
Pico32x.pwm_irq_cnt = pwm.irq_reload;
|
|
}
|
|
|
|
static void do_pwm_irq(SH2 *sh2, unsigned int m68k_cycles)
|
|
{
|
|
p32x_trigger_irq(sh2, m68k_cycles, P32XI_PWM);
|
|
|
|
if (Pico32x.regs[0x30 / 2] & P32XP_RTP) {
|
|
p32x_event_schedule(m68k_cycles, P32X_EVENT_PWM, pwm.cycles / 3 + 1);
|
|
// note: might recurse
|
|
p32x_dreq1_trigger();
|
|
}
|
|
}
|
|
|
|
static int convert_sample(unsigned int v)
|
|
{
|
|
if (v == 0)
|
|
return 0;
|
|
if (v > pwm.cycles)
|
|
v = pwm.cycles;
|
|
return (v * 2 - 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) \
|
|
consume_fifo_do(sh2, m68k_cycles, cycles_diff); \
|
|
}
|
|
|
|
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;
|
|
|
|
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);
|
|
|
|
// this is for recursion from dreq1 writes
|
|
pwm.doing_fifo = 1;
|
|
|
|
for (; sh2_cycles_diff >= pwm.cycles; sh2_cycles_diff -= pwm.cycles)
|
|
{
|
|
if (Pico32x.pwm_p[0] > 0) {
|
|
mem->pwm_index[0] = (mem->pwm_index[0]+1) % 4;
|
|
Pico32x.pwm_p[0]--;
|
|
pwm.current[0] = convert_sample(fifo_l[mem->pwm_index[0]]);
|
|
sum |= pwm.current[0];
|
|
}
|
|
if (Pico32x.pwm_p[1] > 0) {
|
|
mem->pwm_index[1] = (mem->pwm_index[1]+1) % 4;
|
|
Pico32x.pwm_p[1]--;
|
|
pwm.current[1] = convert_sample(fifo_r[mem->pwm_index[1]]);
|
|
sum |= pwm.current[1];
|
|
}
|
|
|
|
mem->pwm[pwm.ptr * 2 ] = pwm.current[0];
|
|
mem->pwm[pwm.ptr * 2 + 1] = pwm.current[1];
|
|
pwm.ptr = (pwm.ptr + 1) & (PWM_BUFF_LEN - 1);
|
|
|
|
if (--Pico32x.pwm_irq_cnt == 0) {
|
|
Pico32x.pwm_irq_cnt = pwm.irq_reload;
|
|
do_pwm_irq(sh2, 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)
|
|
{
|
|
unsigned int pwm_now = m68k_now * 3;
|
|
int cycles_diff_sh2;
|
|
|
|
if (pwm.cycles == 0)
|
|
return 0;
|
|
|
|
cycles_diff_sh2 = pwm_now - Pico32x.pwm_cycle_p;
|
|
if (cycles_diff_sh2 >= pwm.cycles)
|
|
consume_fifo_do(sh2, m68k_now, cycles_diff_sh2);
|
|
|
|
if (!((Pico32x.sh2irq_mask[0] | Pico32x.sh2irq_mask[1]) & 1))
|
|
return 0; // masked by everyone
|
|
|
|
cycles_diff_sh2 = pwm_now - Pico32x.pwm_cycle_p;
|
|
return (Pico32x.pwm_irq_cnt * pwm.cycles
|
|
- cycles_diff_sh2) / 3 + 1;
|
|
}
|
|
|
|
void p32x_pwm_schedule(unsigned int m68k_now)
|
|
{
|
|
int after = p32x_pwm_schedule_(NULL, m68k_now);
|
|
if (after != 0)
|
|
p32x_event_schedule(m68k_now, P32X_EVENT_PWM, after);
|
|
}
|
|
|
|
void p32x_pwm_schedule_sh2(SH2 *sh2)
|
|
{
|
|
int after = p32x_pwm_schedule_(sh2, sh2_cycles_done_m68k(sh2));
|
|
if (after != 0)
|
|
p32x_event_schedule_sh2(sh2, P32X_EVENT_PWM, after);
|
|
}
|
|
|
|
void p32x_pwm_sync_to_sh2(SH2 *sh2)
|
|
{
|
|
int m68k_cycles = sh2_cycles_done_m68k(sh2);
|
|
consume_fifo(sh2, m68k_cycles);
|
|
}
|
|
|
|
void p32x_pwm_irq_event(unsigned int m68k_now)
|
|
{
|
|
p32x_pwm_schedule(m68k_now);
|
|
}
|
|
|
|
unsigned int p32x_pwm_read16(unsigned int a, SH2 *sh2,
|
|
unsigned int m68k_cycles)
|
|
{
|
|
unsigned int d = 0;
|
|
|
|
consume_fifo(sh2, m68k_cycles);
|
|
|
|
a &= 0x0e;
|
|
switch (a/2) {
|
|
case 0/2: // control
|
|
case 2/2: // cycle
|
|
d = Pico32x.regs[(0x30 + a) / 2];
|
|
break;
|
|
|
|
case 4/2: // L ch
|
|
if (Pico32x.pwm_p[0] == 3)
|
|
d |= P32XP_FULL;
|
|
else if (Pico32x.pwm_p[0] == 0)
|
|
d |= P32XP_EMPTY;
|
|
break;
|
|
|
|
case 6/2: // R ch
|
|
case 8/2: // MONO
|
|
if (Pico32x.pwm_p[1] == 3)
|
|
d |= P32XP_FULL;
|
|
else if (Pico32x.pwm_p[1] == 0)
|
|
d |= P32XP_EMPTY;
|
|
break;
|
|
}
|
|
|
|
elprintf(EL_PWM, "pwm: %u: r16 %02x %04x (p %d %d)",
|
|
m68k_cycles, a, d, Pico32x.pwm_p[0], Pico32x.pwm_p[1]);
|
|
return d;
|
|
}
|
|
|
|
void p32x_pwm_write16(unsigned int a, unsigned int d,
|
|
SH2 *sh2, unsigned int m68k_cycles)
|
|
{
|
|
unsigned short *fifo;
|
|
int idx;
|
|
|
|
elprintf(EL_PWM, "pwm: %u: w16 %02x %04x (p %d %d)",
|
|
m68k_cycles, a & 0x0e, d, Pico32x.pwm_p[0], Pico32x.pwm_p[1]);
|
|
|
|
consume_fifo(sh2, m68k_cycles);
|
|
|
|
a &= 0x0e;
|
|
switch (a/2) {
|
|
case 0/2: // control
|
|
// 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; // ?
|
|
break;
|
|
case 2/2: // cycle
|
|
Pico32x.regs[0x32 / 2] = d & 0x0fff;
|
|
p32x_pwm_ctl_changed();
|
|
break;
|
|
case 8/2: // MONO
|
|
case 6/2: // R ch
|
|
fifo = Pico32xMem->pwm_fifo[1];
|
|
idx = Pico32xMem->pwm_index[1];
|
|
if (Pico32x.pwm_p[1] < 3)
|
|
Pico32x.pwm_p[1]++;
|
|
else {
|
|
// fifo[(idx+1) % 4] = fifo[idx];
|
|
idx = (idx+1) % 4;
|
|
Pico32xMem->pwm_index[0] = idx;
|
|
}
|
|
fifo[(idx+Pico32x.pwm_p[1]) % 4] = (d - 1) & 0x0fff;
|
|
if (a != 8) break; // fallthrough if MONO
|
|
case 4/2: // L ch
|
|
fifo = Pico32xMem->pwm_fifo[0];
|
|
idx = Pico32xMem->pwm_index[0];
|
|
if (Pico32x.pwm_p[0] < 3)
|
|
Pico32x.pwm_p[0]++;
|
|
else {
|
|
// fifo[(idx+1) % 4] = fifo[idx];
|
|
idx = (idx+1) % 4;
|
|
Pico32xMem->pwm_index[0] = idx;
|
|
}
|
|
fifo[(idx+Pico32x.pwm_p[0]) % 4] = (d - 1) & 0x0fff;
|
|
break;
|
|
}
|
|
}
|
|
|
|
void p32x_pwm_update(int *buf32, int length, int stereo)
|
|
{
|
|
short *pwmb;
|
|
int step;
|
|
int p = 0;
|
|
int xmd;
|
|
|
|
consume_fifo(NULL, SekCyclesDone());
|
|
|
|
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;
|
|
|
|
if (stereo)
|
|
{
|
|
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];
|
|
*buf32++ += pwmb[0];
|
|
|
|
p += step;
|
|
pwmb += (p >> 16) * 2;
|
|
p &= 0xffff;
|
|
}
|
|
}
|
|
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;
|
|
|
|
p += step;
|
|
pwmb += (p >> 16) * 2;
|
|
p &= 0xffff;
|
|
buf32 += 2;
|
|
}
|
|
}
|
|
}
|
|
else
|
|
{
|
|
// mostly unused
|
|
while (length-- > 0) {
|
|
*buf32++ += pwmb[0];
|
|
|
|
p += step;
|
|
pwmb += (p >> 16) * 2;
|
|
p &= 0xffff;
|
|
}
|
|
}
|
|
|
|
elprintf(EL_PWM, "pwm_update: pwm.ptr %d, len %d, step %04x, done %d",
|
|
pwm.ptr, length, step, (pwmb - Pico32xMem->pwm) / 2);
|
|
|
|
out:
|
|
pwm.ptr = 0;
|
|
pwm.silent = pwm.current[0] == 0 && pwm.current[1] == 0;
|
|
}
|
|
|
|
void p32x_pwm_state_loaded(void)
|
|
{
|
|
int cycles_diff_sh2;
|
|
|
|
p32x_pwm_ctl_changed();
|
|
|
|
// for old savestates
|
|
cycles_diff_sh2 = Pico.t.m68c_cnt * 3 - Pico32x.pwm_cycle_p;
|
|
if (cycles_diff_sh2 >= pwm.cycles || cycles_diff_sh2 < 0) {
|
|
Pico32x.pwm_irq_cnt = pwm.irq_reload;
|
|
Pico32x.pwm_cycle_p = Pico.t.m68c_cnt * 3;
|
|
p32x_pwm_schedule(Pico.t.m68c_cnt);
|
|
}
|
|
}
|
|
|
|
// vim:shiftwidth=2:ts=2:expandtab
|