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mcd, some improvements (dma timing, interrupt handling)

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This commit is contained in:
kub 2024-04-19 21:08:09 +02:00
parent 4447902711
commit 691abdfa0f
3 changed files with 22 additions and 19 deletions
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15
pico/cd/cdc.c
View file

@ -66,6 +66,7 @@
/* PicoDrive: doing DMA at once, not using callbacks */
//#define DMA_BYTES_PER_LINE 512
#define DMA_CYCLES_PER_BYTE 4 // or 6?
enum dma_type {
word_ram_0_dma_w = 1,
@ -354,7 +355,7 @@ void cdc_dma_update(void)
do_dma(cdc.dma_w, cdc.dbc + 1);
/* reset data byte counter (DBCH bits 4-7 should be set to 1) */
cdc.dbc = 0xf000;
cdc.dbc = 0xffff;
/* clear !DTEN and !DTBSY */
cdc.ifstat |= (BIT_DTBSY | BIT_DTEN);
@ -405,6 +406,9 @@ int cdc_decoder_update(uint8 header[4])
/* set !VALST */
cdc.stat[3] = 0x00;
/* set CRCOK bit */
cdc.stat[0] = BIT_DECEN;
/* pending decoder interrupt */
cdc.ifstat &= ~BIT_DECI;
@ -602,7 +606,7 @@ void cdc_reg_w(unsigned char data)
}
if (cdc.dma_w)
pcd_event_schedule_s68k(PCD_EVENT_DMA, cdc.dbc / 2);
pcd_event_schedule_s68k(PCD_EVENT_DMA, cdc.dbc * DMA_CYCLES_PER_BYTE);
}
Pico_mcd->s68k_regs[0x04+1] = 0x07;
@ -643,11 +647,8 @@ void cdc_reg_w(unsigned char data)
case 0x0a: /* CTRL0 */
{
/* set CRCOK bit only if decoding is enabled */
cdc.stat[0] = data & BIT_DECEN;
/* reset DECI if decoder turned off */
if (!cdc.stat[0])
if (!(data & BIT_DECEN))
cdc.ifstat |= BIT_DECI;
/* update decoding mode */
@ -827,7 +828,7 @@ unsigned short cdc_host_r(void)
if ((int16)cdc.dbc <= 0)
{
/* reset data byte counter (DBCH bits 4-7 should be set to 1) */
cdc.dbc = 0xf000;
cdc.dbc = 0xffff;
/* clear !DTEN and !DTBSY */
cdc.ifstat |= (BIT_DTBSY | BIT_DTEN);

5
pico/cd/mcd.c
View file

@ -149,7 +149,7 @@ static void pcd_cdc_event(unsigned int now)
/* reset CDD command wait flag */
Pico_mcd->s68k_regs[0x4b] = 0xf0;
if (Pico_mcd->s68k_regs[0x33] & PCDS_IEN4) {
if ((Pico_mcd->s68k_regs[0x33] & PCDS_IEN4) && (Pico_mcd->s68k_regs[0x37] & 4)) {
elprintf(EL_INTS|EL_CD, "s68k: cdd irq 4");
pcd_irq_s68k(4, 1);
}
@ -209,8 +209,7 @@ void pcd_event_schedule(unsigned int now, enum pcd_event event, int after)
void pcd_event_schedule_s68k(enum pcd_event event, int after)
{
if (SekCyclesLeftS68k > after)
SekEndRunS68k(after);
SekEndRunS68k(after);
pcd_event_schedule(SekCyclesDoneS68k(), event, after);
}

21
pico/cd/memory.c
View file

@ -142,7 +142,7 @@ static u32 m68k_reg_read16(u32 a)
// comm flag/cmd/status (0xE-0x2F)
m68k_comm_check(a);
d = (Pico_mcd->s68k_regs[a]<<8) | Pico_mcd->s68k_regs[a+1];
goto end;
return d;
}
elprintf(EL_UIO, "m68k_regs FIXME invalid read @ %02x", a);
@ -172,7 +172,8 @@ void m68k_reg_write8(u32 a, u32 d)
elprintf(EL_INTS, "m68k: s68k irq 2");
pcd_sync_s68k(SekCyclesDone(), 0);
pcd_irq_s68k(2, 1);
}
} else
pcd_irq_s68k(2, 0);
return;
case 1:
d &= 3;
@ -456,9 +457,9 @@ void s68k_reg_write8(u32 a, u32 d)
case 0x33: // IRQ mask
elprintf(EL_CDREGS|EL_CD, "s68k irq mask: %02x", d);
d &= 0x7e;
if ((d ^ Pico_mcd->s68k_regs[0x33]) & d & PCDS_IEN4) {
if ((d ^ Pico_mcd->s68k_regs[0x33]) & PCDS_IEN4) {
// XXX: emulate pending irq instead?
if (Pico_mcd->s68k_regs[0x37] & 4) {
if ((d & PCDS_IEN4) && (Pico_mcd->s68k_regs[0x37] & 4)) {
elprintf(EL_INTS, "cdd export irq 4 (unmask)");
pcd_irq_s68k(4, 1);
}
@ -474,11 +475,12 @@ void s68k_reg_write8(u32 a, u32 d)
case 0x37: {
u32 d_old = Pico_mcd->s68k_regs[0x37];
Pico_mcd->s68k_regs[0x37] = d & 7;
if ((d&4) && !(d_old&4)) {
if ((d ^ d_old) & 4) {
// ??
pcd_event_schedule_s68k(PCD_EVENT_CDC, 12500000/75);
if (d & 4)
pcd_event_schedule_s68k(PCD_EVENT_CDC, 12500000/75);
if (Pico_mcd->s68k_regs[0x33] & PCDS_IEN4) {
if ((d & 4) && (Pico_mcd->s68k_regs[0x33] & PCDS_IEN4)) {
elprintf(EL_INTS, "cdd export irq 4");
pcd_irq_s68k(4, 1);
}
@ -1223,9 +1225,10 @@ static void m68k_mem_setup_cd(void);
PICO_INTERNAL void PicoMemSetupCD(void)
{
if (!Pico_mcd)
if (!Pico_mcd) {
Pico_mcd = plat_mmap(0x05000000, sizeof(mcd_state), 0, 0);
memset(Pico_mcd, 0, sizeof(mcd_state));
memset(Pico_mcd, 0, sizeof(mcd_state));
}
pcd_base_address = (Pico.romsize > 0x20000 ? 0x400000 : 0x000000);
// setup default main68k map