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sound, faster resampler for SMS FM

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This commit is contained in:
kub 2023-11-23 20:50:25 +01:00
parent 250c8ffbc0
commit 43ef4071da
3 changed files with 67 additions and 38 deletions
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103
pico/sound/sound.c
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@ -27,8 +27,11 @@ s16 cdda_out_buffer[2*1152];
// sn76496
extern int *sn76496_regs;
// FM resampling polyphase FIR
static resampler_t *fmresampler;
static int (*PsndFMUpdate)(s32 *buffer, int length, int stereo, int is_buf_empty);
// ym2413
#define YM2413_CLK 3579545
static OPLL *opll = NULL;
static OPLL old_opll;
static struct {
@ -36,6 +39,14 @@ static struct {
uint8_t reg[sizeof(opll->reg)];
} opll_buf;
void YM2413_regWrite(unsigned data){
OPLL_writeIO(opll,0,data);
}
void YM2413_dataWrite(unsigned data){
OPLL_writeIO(opll,1,data);
}
PICO_INTERNAL void *YM2413GetRegs(void)
{
memcpy(opll_buf.reg, opll->reg, sizeof(opll->reg));
@ -54,12 +65,9 @@ PICO_INTERNAL void YM2413UnpackState(void)
opll->adr = opll_buf.adr;
}
static resampler_t *fmresampler;
static int (*PsndFMUpdate)(s32 *buffer, int length, int stereo, int is_buf_empty);
PICO_INTERNAL void PsndInit(void)
{
opll = OPLL_new(YM2413_CLK, PicoIn.sndRate);
opll = OPLL_new(OSC_NTSC/15, OSC_NTSC/15/72);
OPLL_setChipType(opll,0);
OPLL_reset(opll);
}
@ -95,7 +103,25 @@ static int YM2612UpdateFIR(s32 *buffer, int length, int stereo, int is_buf_empty
return ymchans;
}
static void YM2612_setup_FIR(int inrate, int outrate, int stereo)
// resample SMS FM from its native 49716Hz/49262Hz with polyphase FIR filter
static void YM2413Update(s32 *buffer, int length, int stereo)
{
while (length-- > 0) {
int16_t getdata = OPLL_calc(opll) * 3;
*buffer++ = getdata;
buffer += stereo; // only left for stereo, to be mixed to right later
}
}
static int YM2413UpdateFIR(s32 *buffer, int length, int stereo, int is_buf_empty)
{
if (!is_buf_empty) memset(buffer, 0, (length << stereo) * sizeof(*buffer));
resampler_update(fmresampler, buffer, length, YM2413Update);
return 0;
}
// FIR setup, looks for a close enough rational number matching the ratio
static void YMFM_setup_FIR(int inrate, int outrate, int stereo)
{
int mindiff = 999;
int diff, mul, div;
@ -132,21 +158,31 @@ void PsndRerate(int preserve_state)
void *state = NULL;
int target_fps = Pico.m.pal ? 50 : 60;
int target_lines = Pico.m.pal ? 313 : 262;
int sms_clock = Pico.m.pal ? OSC_PAL/15 : OSC_NTSC/15;
int ym2612_clock = Pico.m.pal ? OSC_PAL/7 : OSC_NTSC/7;
int ym2612_rate = YM2612_NATIVE_RATE();
int ym2413_rate = (sms_clock + 36) / 72;
if (preserve_state) {
state = malloc(0x204);
if (state == NULL) return;
ym2612_pack_state();
memcpy(state, YM2612GetRegs(), 0x204);
if (opll != NULL)
memcpy(&old_opll, opll, sizeof(OPLL)); // remember old state
}
if ((PicoIn.opt & POPT_EN_FM_FILTER) && ym2612_rate != PicoIn.sndRate) {
if (PicoIn.AHW & PAHW_SMS) {
OPLL_setRate(opll, ym2413_rate);
OPLL_reset(opll);
YMFM_setup_FIR(ym2413_rate, PicoIn.sndRate, 0);
PsndFMUpdate = YM2413UpdateFIR;
} else if ((PicoIn.opt & POPT_EN_FM_FILTER) && ym2612_rate != PicoIn.sndRate) {
// polyphase FIR resampler, resampling directly from native to output rate
YM2612Init(ym2612_clock, ym2612_rate,
((PicoIn.opt&POPT_DIS_FM_SSGEG) ? 0 : ST_SSG) |
((PicoIn.opt&POPT_EN_FM_DAC) ? ST_DAC : 0));
YM2612_setup_FIR(ym2612_rate, PicoIn.sndRate, PicoIn.opt & POPT_EN_STEREO);
YMFM_setup_FIR(ym2612_rate, PicoIn.sndRate, PicoIn.opt & POPT_EN_STEREO);
PsndFMUpdate = YM2612UpdateFIR;
} else {
YM2612Init(ym2612_clock, PicoIn.sndRate,
@ -158,20 +194,17 @@ void PsndRerate(int preserve_state)
// feed it back it's own registers, just like after loading state
memcpy(YM2612GetRegs(), state, 0x204);
ym2612_unpack_state();
if (opll != NULL) {
memcpy(&opll->adr, &old_opll.adr, sizeof(OPLL)-20); // restore old state
OPLL_forceRefresh(opll);
}
}
if (preserve_state) memcpy(state, sn76496_regs, 28*4); // remember old state
SN76496_init(Pico.m.pal ? OSC_PAL/15 : OSC_NTSC/15, PicoIn.sndRate);
if (preserve_state) memcpy(sn76496_regs, state, 28*4); // restore old state
if(opll != NULL){
if (preserve_state) memcpy(&old_opll, opll, sizeof(OPLL)); // remember old state
OPLL_setRate(opll, PicoIn.sndRate);
OPLL_reset(opll);
if (preserve_state) memcpy(&opll->adr, &old_opll.adr, sizeof(OPLL)-20); // restore old state
OPLL_forceRefresh(opll);
}
if (state)
free(state);
@ -284,12 +317,12 @@ PICO_INTERNAL void PsndDoPSG(int cyc_to)
SN76496Update(PicoIn.sndOut + pos, len, stereo);
}
#if 0
PICO_INTERNAL void PsndDoYM2413(int cyc_to)
PICO_INTERNAL void PsndDoSMSFM(int cyc_to)
{
int pos, len;
int stereo = 0;
s16 *buf;
s32 *buf32 = PsndBuffer;
s16 *buf = PicoIn.sndOut;
// nothing to do if sound is off
if (!PicoIn.sndOut) return;
@ -312,22 +345,15 @@ PICO_INTERNAL void PsndDoYM2413(int cyc_to)
pos <<= 1;
}
buf = PicoIn.sndOut + pos;
while (len-- > 0) {
int16_t getdata = OPLL_calc(opll) * 3;
*buf++ += getdata;
buf += stereo; // only left for stereo, to be mixed to right later
if (Pico.m.hardware & PMS_HW_FMUSED) {
buf += pos;
PsndFMUpdate(buf32, len, 0, 0);
while (len--) {
*buf++ += *buf32++;
buf += stereo;
}
}
}
#endif
void YM2413_regWrite(unsigned data){
OPLL_writeIO(opll,0,data);
}
void YM2413_dataWrite(unsigned data){
OPLL_writeIO(opll,1,data);
}
PICO_INTERNAL void PsndDoFM(int cyc_to)
{
@ -515,6 +541,7 @@ PICO_INTERNAL void PsndGetSamples(int y)
static int PsndRenderMS(int offset, int length)
{
s32 *buf32 = PsndBuffer;
int stereo = (PicoIn.opt & 8) >> 3;
int psglen = ((Pico.snd.psg_pos+0x80000) >> 20);
int ym2413len = ((Pico.snd.ym2413_pos+0x80000) >> 20);
@ -536,11 +563,11 @@ static int PsndRenderMS(int offset, int length)
s16 *ym2413buf = PicoIn.sndOut + (ym2413len << stereo);
Pico.snd.ym2413_pos += (length-ym2413len) << 20;
int len = (length-ym2413len);
if (PicoIn.opt & POPT_EN_YM2413){
while (len-- > 0) {
int16_t getdata = OPLL_calc(opll) * 3;
*ym2413buf += getdata;
ym2413buf += 1<<stereo;
if (Pico.m.hardware & PMS_HW_FMUSED) {
PsndFMUpdate(buf32, len, 0, 0);
while (len--) {
*ym2413buf++ += *buf32++;
ym2413buf += stereo;
}
}
}