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view ymz263b.c @ 2490:a0837ea61fda
Get static images working in GL mode
author | Michael Pavone <pavone@retrodev.com> |
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date | Wed, 17 Apr 2024 21:54:44 -0700 |
parents | e8eba0cd5444 |
children |
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#include <string.h> #include "ymz263b.h" #include "backend.h" enum { YMZ_SELT, YMZ_LSI_TEST, YMZ_TIMER0_LOW, YMZ_TIMER0_HIGH, YMZ_TIMER_BASE, YMZ_TIMER1, YMZ_TIMER2_LOW, YMZ_TIMER2_HIGH, YMZ_TIMER_CTRL, YMZ_PCM_PLAY_CTRL, YMZ_PCM_VOL, YMZ_PCM_DATA, YMZ_PCM_CTRL, YMZ_MIDI_CTRL, YMZ_MIDI_DATA }; //YMZ_SELT #define BIT_SELT 0x01 //YMZ_TIMER_CTRL #define BIT_ST0 0x01 #define BIT_ST1 0x02 #define BIT_ST2 0x04 #define BIT_STBC 0x08 #define BIT_T0_MSK 0x10 #define BIT_T1_MSK 0x20 #define BIT_T2_MSK 0x40 #define TIMER_RUN_MASK (BIT_ST0|BIT_ST1|BIT_ST2) #define TIMER_INT_MASK (BIT_T0_MSK|BIT_T1_MSK|BIT_T2_MSK) //YMZ_PCM_PLAY_CTRL #define BIT_ADP_ST 0x01 #define BIT_PLY_REC 0x02 #define BIT_PCM 0x04 #define BIT_PAN_L 0x20 #define BIT_PAN_R 0x40 #define BIT_ADP_RST 0x80 //YMZ_PCM_FIFO_CTRL #define BIT_DMA_ENB 0x01 #define BIT_MSK_FIF 0x02 #define BIT_DMA_MOD 0x80 //YMZ_MIDI_CTRL #define BIT_MSK_RRQ 0x01 #define BIT_MRC_RST 0x02 #define BIT_MSK_TRQ 0x04 #define BIT_MTR_RST 0x08 #define BIT_MSK_MOV 0x10 #define BIT_MSK_POV 0x20 #define STATUS_FIF1 0x01 #define STATUS_FIF2 0x02 #define STATUS_RRQ 0x04 #define STATUS_TRQ 0x08 #define STATUS_T0 0x10 #define STATUS_T1 0x20 #define STATUS_T2 0x40 #define STATUS_OV 0x80 #define TIMER_DIVIDER 32 #define MIDI_BYTE_DIVIDER 170 #define PCM_BASE_DIVIDER 12 #define FIFO_EMPTY 255 void ymz263b_init(ymz263b *ymz, uint32_t master_clock, uint32_t clock_divider) { memset(ymz, 0, sizeof(*ymz)); ymz->clock_inc = clock_divider * TIMER_DIVIDER; ymz->audio = render_audio_source("YMZ263B", master_clock, ymz->clock_inc * PCM_BASE_DIVIDER, 2); ymz->base_regs[YMZ_SELT] = 1; ymz->pcm[0].regs[0] = BIT_ADP_RST; ymz->pcm[1].regs[0] = BIT_ADP_RST; ymz->pcm[0].counter = 1; ymz->pcm[0].fifo_read = FIFO_EMPTY; ymz->pcm[1].counter = 1; ymz->pcm[1].fifo_read = FIFO_EMPTY; ymz->midi_regs[0] = BIT_MTR_RST | BIT_MRC_RST; ymz->midi_trs.read = ymz->midi_rcv.read = FIFO_EMPTY; ymz->status = 0; ymz->pcm_counter = PCM_BASE_DIVIDER; } void ymz263b_free(ymz263b *ymz) { render_free_source(ymz->audio); } void ymz263b_adjust_master_clock(ymz263b *ymz, uint32_t master_clock) { render_audio_adjust_clock(ymz->audio, master_clock, ymz->clock_inc * PCM_BASE_DIVIDER); } static uint8_t fifo_empty(ymz_midi_fifo *fifo) { return fifo->read == FIFO_EMPTY; } static uint8_t fifo_read(ymz_midi_fifo *fifo) { uint8_t ret = fifo->fifo[fifo->read++]; fifo->read &= 15; if (fifo->read == fifo->write) { fifo->read = FIFO_EMPTY; } return ret; } static uint8_t fifo_write(ymz_midi_fifo *fifo, uint8_t value) { uint8_t overflow = fifo->read == fifo->write; if (fifo->read == FIFO_EMPTY) { fifo->read = fifo->write; } fifo->fifo[fifo->write++] = value; fifo->write &= 15; return overflow; } static uint8_t fifo_size(ymz_midi_fifo *fifo) { if (fifo->read == FIFO_EMPTY) { return 0; } if (fifo->read == fifo->write) { return 16; } return (fifo->write - fifo->read) & 15; } static uint8_t pcm_fifo_empty(ymz263b_pcm *pcm) { return pcm->fifo_read == FIFO_EMPTY; } static uint16_t pcm_fifo_read(ymz263b_pcm *pcm, uint8_t nibbles) { uint16_t ret = 0; for (; nibbles && !pcm_fifo_empty(pcm); nibbles--) { ret <<= 4; if (pcm->nibble) { ret |= pcm->fifo[pcm->fifo_read++] & 0xF; pcm->fifo_read &= sizeof(pcm->fifo) - 1; pcm->nibble = 0; if (pcm->fifo_read == pcm->fifo_write) { pcm->fifo_read = FIFO_EMPTY; } } else { ret |= pcm->fifo[pcm->fifo_read] >> 4; pcm->nibble = 1; } } return ret; } static uint8_t pcm_fifo_write(ymz263b_pcm *pcm, uint8_t nibbles, uint16_t value) { uint8_t overflow = 0; value <<= (4 - nibbles) * 4; for (; nibbles; nibbles--) { if (pcm->nibble_write) { pcm->fifo[pcm->fifo_write++] |= value >> 12; pcm->fifo_write &= sizeof(pcm->fifo) - 1; pcm->nibble_write = 0; } else { if (pcm->fifo_read == FIFO_EMPTY) { pcm->fifo_read = pcm->fifo_write; } else if (pcm->fifo_read == pcm->fifo_write) { overflow = 1; } pcm->fifo[pcm->fifo_write] = value >> 8 & 0xF0; pcm->nibble_write = 1; } value <<= 4; } return overflow; } static uint8_t pcm_fifo_free(ymz263b_pcm *pcm) { if (pcm->fifo_read == FIFO_EMPTY) { return sizeof(pcm->fifo); } return (pcm->fifo_read - pcm->fifo_write) & (sizeof(pcm->fifo) - 1); } static uint8_t pcm_dividers[] = {1, 2, 4, 6, 8}; static void ymz263b_pcm_run(ymz263b *ymz, ymz263b_pcm *pcm, int16_t *output) { if ((pcm->regs[0] & (BIT_ADP_RST|BIT_ADP_ST)) != BIT_ADP_ST) { //PCM channel is either in reset or not started return; } pcm->counter--; if (!pcm->counter) { uint8_t fs = pcm->regs[0] >> 3 & 3; if (!(pcm->regs[0] & BIT_PCM)) { //ADPCM can't use 44.1 kHz, but gains 5.5125 kHz fs++; } pcm->counter = pcm_dividers[fs]; uint8_t nibbles = (pcm->regs[3] >> 5 & 3) + 2; if (nibbles > 4) { //4-bit format is encoded as the highest value for some reason nibbles = 1; } //adlib driver suggests that FMT should be 3 for 4-bit ADPCM, but Copera games seem to use zero //maybe FMT is ignored for ADPCM mode? if (!(pcm->regs[0] & BIT_PCM)) { nibbles = 1; } //adlib driver sets SELF to 5 for playback to trigger int "when less than 32 bytes in fifo" aka 96 bytes free //adlib driver sets SELF to 3 for recording to trigger int "when more than 64 bytes in fifo" aka 64 bytes free uint8_t fifo_threshold = ((pcm->regs[3] >> 2 & 7) + 1) << 4; if (pcm->regs[0] & BIT_PLY_REC) { //Playback mode uint16_t sample = pcm_fifo_read(pcm, nibbles); if (pcm->regs[0] & BIT_PCM) { //TODO: Presumably SELT bit impacts this if (sample & (1 << (nibbles * 4 - 1))) { sample |= 0xFFF << (nibbles * 4); } switch (nibbles) { case 1: sample <<= 8; break; case 2: sample <<= 4; break; case 4: //PCem's code seems to imply the "hole" is in the middle //but that's ugly so hoping it's incorrect sample >>= 4; break; } pcm->output = sample; if (pcm->output & 0x800) { pcm->output |= 0xF000; } else { pcm->output &= 0x0FFF; } } else { //This uses superctr's YMZ280B decoder as a reference //That chip has 16-bit output, but supposedly is compatible //with ADPCM data from the YM263B //Currently I'm 'calculating as 16-bit internally and //truncating to 12-bit on output uint16_t mag = sample & 7; int32_t delta = (((mag << 1) + 1) * pcm->adpcm_step) >> 3; if (delta > 0x7FFF) { delta = 0x7FFF; } if (sample & 8) { delta = -delta; } int32_t value = ((int16_t)pcm->output); value = (value * 254) >> 8; value += delta; if (value > 0x7FFF) { value = 0x7FFF; } else if (value < -0x8000) { value = -0x8000; } pcm->output = value; static const uint16_t step_adjust[8] = { 230, 230, 230, 230, 307, 409, 512, 614 }; int32_t step = pcm->adpcm_step * step_adjust[mag]; if (step > 24576) { step = 24576; } else if (step < 127) { step = 127; } pcm->adpcm_step = step; } if (pcm_fifo_free(pcm) > fifo_threshold) { ymz->status |= pcm == &ymz->pcm[0] ? STATUS_FIF1 : STATUS_FIF2; } } else { //Recording mode //TODO: support recording actual audio input if (pcm_fifo_write(pcm, nibbles, 0)) { ymz->status |= STATUS_OV; } if (pcm_fifo_free(pcm) < fifo_threshold) { ymz->status |= pcm == &ymz->pcm[0] ? STATUS_FIF1 : STATUS_FIF2; } } } if (pcm->regs[0] & BIT_PLY_REC) { //TODO: Volume int16_t value = pcm->output; if (!(pcm->regs[0] & BIT_PCM)) { value >>= 4; } if (pcm->regs[0] & BIT_PAN_L) { output[0] += value; } if (pcm->regs[0] & BIT_PAN_R) { output[1] += value; } } } void ymz263b_run(ymz263b *ymz, uint32_t target_cycle) { uint8_t timer_ctrl = ymz->base_regs[YMZ_TIMER_CTRL]; for (; ymz->cycle < target_cycle; ymz->cycle += ymz->clock_inc) { if (timer_ctrl & BIT_ST0) { ymz->timers[0]--; if (!ymz->timers[0]) { ymz->timers[0] = ymz->base_regs[YMZ_TIMER0_HIGH] << 8 | ymz->base_regs[YMZ_TIMER0_LOW]; ymz->status |= STATUS_T0; } } if (timer_ctrl & BIT_STBC) { ymz->timers[3]--; ymz->timers[3] &= 0xFFF; if (!ymz->timers[3]) { ymz->timers[3] = ymz->base_regs[YMZ_TIMER1] << 8 & 0xF00; ymz->timers[3] |= ymz->base_regs[YMZ_TIMER_BASE]; if (timer_ctrl & BIT_ST1) { ymz->timers[1]--; if (!ymz->timers[1]) { ymz->timers[1] = ymz->base_regs[YMZ_TIMER1] >> 4; ymz->status |= STATUS_T1; } } if (timer_ctrl & BIT_ST2) { ymz->timers[2]--; if (!ymz->timers[2]) { ymz->timers[2] = ymz->base_regs[YMZ_TIMER2_HIGH] << 8 | ymz->base_regs[YMZ_TIMER2_LOW]; ymz->status |= STATUS_T2; } } } } if (!(ymz->midi_regs[0] & BIT_MTR_RST) && !fifo_empty(&ymz->midi_trs)) { if (ymz->midi_transmit) { --ymz->midi_transmit; } else { ymz->midi_transmit = MIDI_BYTE_DIVIDER - 1; //TODO: send this byte to MIDI device uint8_t byte = fifo_read(&ymz->midi_trs); printf("MIDI Transmit: %X\n", byte); if (fifo_empty(&ymz->midi_trs)) { ymz->status |= STATUS_TRQ; } } } ymz->pcm_counter--; if (!ymz->pcm_counter) { ymz->pcm_counter = PCM_BASE_DIVIDER; int16_t output[2] = {0, 0}; ymz263b_pcm_run(ymz, &ymz->pcm[0], output); ymz263b_pcm_run(ymz, &ymz->pcm[1], output); render_put_stereo_sample(ymz->audio, output[0], output[1]); } } } static uint32_t predict_fifo_thres(ymz263b *ymz, ymz263b_pcm *pcm) { if ((pcm->regs[0] & (BIT_ADP_RST|BIT_ADP_ST)) != BIT_ADP_ST) { //PCM channel is either in reset or not started return CYCLE_NEVER; } uint32_t next_pcm_cycle = ymz->cycle + ymz->pcm_counter * ymz->clock_inc; next_pcm_cycle += (pcm->counter - 1) * PCM_BASE_DIVIDER * ymz->clock_inc; uint32_t fifo_free = pcm_fifo_free(pcm); //convert to nibbles fifo_free <<= 1; uint32_t fifo_threshold = ((pcm->regs[3] >> 2 & 7) + 1) << 5; uint32_t diff; if (pcm->regs[0] & BIT_PLY_REC) { if (pcm->nibble) { fifo_free++; } diff = fifo_threshold - fifo_free + 1; } else { if (pcm->nibble_write) { fifo_free--; } diff = fifo_free - fifo_threshold + 1; } uint32_t nibbles_per_samp = (pcm->regs[3] >> 5 & 3) + 2; if (nibbles_per_samp > 4) { //4-bit format is encoded as the highest value for some reason nibbles_per_samp = 1; } uint8_t fs = pcm->regs[0] >> 3 & 3; if (!(pcm->regs[0] & BIT_PCM)) { //ADPCM can't use 44.1 kHz, but gains 5.5125 kHz fs++; //see note in PCM playback code nibbles_per_samp = 1; } diff /= nibbles_per_samp; next_pcm_cycle += diff * PCM_BASE_DIVIDER * pcm_dividers[fs] * ymz->clock_inc; return next_pcm_cycle; } uint32_t ymz263b_next_int(ymz263b *ymz) { //TODO: Handle MIDI receive interrupts uint8_t enabled_ints = (~ymz->base_regs[YMZ_TIMER_CTRL]) & TIMER_INT_MASK; if (!(ymz->base_regs[YMZ_MIDI_CTRL] & (BIT_MTR_RST|BIT_MSK_TRQ))) { enabled_ints |= STATUS_TRQ; } if (!(ymz->pcm[0].regs[3] & BIT_MSK_FIF)) { enabled_ints |= STATUS_FIF1; } if (!(ymz->pcm[1].regs[3] & BIT_MSK_FIF)) { enabled_ints |= STATUS_FIF2; } if (!enabled_ints) { return CYCLE_NEVER; } //Handle currently pending interrupts if (enabled_ints & ymz->status) { return ymz->cycle; } uint32_t ret = CYCLE_NEVER; if (enabled_ints & STATUS_TRQ) { uint8_t bytes = fifo_size(&ymz->midi_trs); if (bytes) { ret = ymz->cycle + (ymz->midi_transmit + 1) * ymz->clock_inc; if (bytes > 1) { ret += MIDI_BYTE_DIVIDER * ymz->clock_inc * (bytes - 1); } } } if (enabled_ints & STATUS_FIF1) { uint32_t next_pcm = predict_fifo_thres(ymz, &ymz->pcm[0]); if (next_pcm < ret) { ret = next_pcm; } } if (enabled_ints & STATUS_FIF2) { uint32_t next_pcm = predict_fifo_thres(ymz, &ymz->pcm[1]); if (next_pcm < ret) { ret = next_pcm; } } enabled_ints >>= 4; //If timers aren't already expired, interrupts can't fire unless the timers are enabled enabled_ints &= ymz->base_regs[YMZ_TIMER_CTRL]; if (!(ymz->base_regs[YMZ_TIMER_CTRL] & BIT_STBC)) { //Timer 1 and Timer 2 depend on the base timer enabled_ints &= 1; } if (enabled_ints & BIT_ST0) { uint32_t t0 = ymz->cycle + (ymz->timers[0] ? ymz->timers[0] : 0x10000) * ymz->clock_inc; if (t0 < ret) { ret = t0; } } if (enabled_ints & (BIT_ST1|BIT_ST2)) { uint32_t base = ymz->cycle + (ymz->timers[3] ? ymz->timers[3] : 0x1000) * ymz->clock_inc; if (base < ret) { uint32_t load = (ymz->base_regs[YMZ_TIMER1] << 8 & 0xF00) | ymz->base_regs[YMZ_TIMER_BASE]; if (!load) { load = 0x1000; } if (enabled_ints & BIT_ST1) { uint32_t t1 = base + (ymz->timers[1] ? ymz->timers[1] - 1 : 0xF) * load * ymz->clock_inc; if (t1 < ret) { ret = t1; } } if (enabled_ints & BIT_ST2) { uint32_t t2 = base + (ymz->timers[2] ? ymz->timers[2] - 1 : 0xFFFF) * load * ymz->clock_inc; if (t2 < ret) { ret = t2; } } } } return ret; } void ymz263b_address_write(ymz263b *ymz, uint8_t value) { ymz->address = value; } void ymz263b_data_write(ymz263b *ymz, uint32_t channel, uint8_t value) { if (channel) { if (ymz->address >= YMZ_PCM_PLAY_CTRL && ymz->address < YMZ_MIDI_CTRL) { if (ymz->address == YMZ_PCM_PLAY_CTRL) { if (((value ^ ymz->pcm[1].regs[0]) & ymz->pcm[1].regs[0]) & BIT_ADP_RST) { //Perform reset on falling edge of reset bit ymz->pcm[1].counter = 1; ymz->pcm[1].fifo_read = FIFO_EMPTY; ymz->pcm[1].nibble = ymz->pcm[1].nibble_write = 0; ymz->pcm[1].output = 0; ymz->pcm[1].adpcm_step = 127; } } ymz->pcm[1].regs[ymz->address - YMZ_PCM_PLAY_CTRL] = value; if (ymz->address == YMZ_PCM_DATA) { pcm_fifo_write(&ymz->pcm[1], 2, value); //Does an overflow here set the overflow statu sflag? } } } else { if (ymz->address < YMZ_PCM_PLAY_CTRL) { if (ymz->address == YMZ_TIMER_CTRL) { uint8_t newly_set = (ymz->base_regs[ymz->address] ^ value) & value; if (newly_set & BIT_ST0) { ymz->timers[0] = ymz->base_regs[YMZ_TIMER0_HIGH] << 8 | ymz->base_regs[YMZ_TIMER0_LOW]; } if (newly_set & BIT_ST1) { ymz->timers[1] = ymz->base_regs[YMZ_TIMER1] >> 4; } if (newly_set & BIT_ST2) { ymz->timers[2] = ymz->base_regs[YMZ_TIMER2_HIGH] << 8 | ymz->base_regs[YMZ_TIMER2_LOW]; } if (newly_set & BIT_STBC) { ymz->timers[0] = (ymz->base_regs[YMZ_TIMER1] << 8 | ymz->base_regs[YMZ_TIMER_BASE]) & 0xFFF; } } ymz->base_regs[ymz->address] = value; } else if (ymz->address < YMZ_MIDI_CTRL) { if (((value ^ ymz->pcm[0].regs[0]) & ymz->pcm[1].regs[0]) & BIT_ADP_RST) { //Perform reset on falling edge of reset bit ymz->pcm[0].counter = 1; ymz->pcm[0].fifo_read = FIFO_EMPTY; ymz->pcm[0].nibble = ymz->pcm[1].nibble_write = 0; ymz->pcm[0].output = 0; ymz->pcm[0].adpcm_step = 127; } ymz->pcm[0].regs[ymz->address - YMZ_PCM_PLAY_CTRL] = value; if (ymz->address == YMZ_PCM_DATA) { pcm_fifo_write(&ymz->pcm[0], 2, value); //Does an overflow here set the overflow statu sflag? } } else { ymz->midi_regs[ymz->address - YMZ_MIDI_CTRL] = value; if (ymz->address == YMZ_MIDI_DATA) { ymz->status &= ~STATUS_TRQ; if (fifo_empty(&ymz->midi_trs)) { ymz->midi_transmit = MIDI_BYTE_DIVIDER - 1; } fifo_write(&ymz->midi_trs, value); } } } } uint8_t ymz263b_data_read(ymz263b *ymz, uint32_t channel) { //TODO: Supposedly only a few registers are actually readable if (channel) { if (ymz->address >= YMZ_PCM_PLAY_CTRL && ymz->address < YMZ_MIDI_CTRL) { if (ymz->address == YMZ_PCM_DATA) { return pcm_fifo_read(&ymz->pcm[1], 2); } return ymz->pcm[1].regs[ymz->address - YMZ_PCM_PLAY_CTRL]; } } else { if (ymz->address < YMZ_PCM_PLAY_CTRL) { return ymz->base_regs[ymz->address]; } else if (ymz->address < YMZ_MIDI_CTRL) { if (ymz->address == YMZ_PCM_DATA) { return pcm_fifo_read(&ymz->pcm[0], 2); } return ymz->pcm[0].regs[ymz->address - YMZ_PCM_PLAY_CTRL]; } else { return ymz->midi_regs[ymz->address - YMZ_MIDI_CTRL]; } } return 0XFF; } uint8_t ymz263b_status_read(ymz263b *ymz) { uint8_t ret = ymz->status; ymz->status = 0;//&= ~(STATUS_T0|STATUS_T1|STATUS_T2); return ret; }