picodrive/pico/32x/sh2soc.c
2013-08-10 19:46:27 +03:00

449 lines
12 KiB
C

/*
* SH2 peripherals/"system on chip"
* (C) notaz, 2013
*
* This work is licensed under the terms of MAME license.
* See COPYING file in the top-level directory.
*
* rough fffffe00-ffffffff map:
* e00-e05 SCI serial communication interface
* e10-e1a FRT free-running timer
* e60-e68 VCRx irq vectors
* e71-e72 DRCR dma selection
* e80-e83 WDT watchdog timer
* e91 SBYCR standby control
* e92 CCR cache control
* ee0 ICR irq control
* ee2 IPRA irq priorities
* ee4 VCRWDT WDT irq vectors
* f00-f17 DIVU
* f40-f7b UBC user break controller
* f80-fb3 DMAC
* fe0-ffb BSC bus state controller
*/
#include "../pico_int.h"
#include "../memory.h"
// DMAC handling
struct dma_chan {
unsigned int sar, dar; // src, dst addr
unsigned int tcr; // transfer count
unsigned int chcr; // chan ctl
// -- dm dm sm sm ts ts ar am al ds dl tb ta ie te de
// ts - transfer size: 1, 2, 4, 16 bytes
// ar - auto request if 1, else dreq signal
// ie - irq enable
// te - transfer end
// de - dma enable
#define DMA_AR (1 << 9)
#define DMA_IE (1 << 2)
#define DMA_TE (1 << 1)
#define DMA_DE (1 << 0)
};
struct dmac {
struct dma_chan chan[2];
unsigned int vcrdma0;
unsigned int unknown0;
unsigned int vcrdma1;
unsigned int unknown1;
unsigned int dmaor;
// -- pr ae nmif dme
// pr - priority: chan0 > chan1 or round-robin
// ae - address error
// nmif - nmi occurred
// dme - DMA master enable
#define DMA_DME (1 << 0)
};
static void dmac_te_irq(SH2 *sh2, struct dma_chan *chan)
{
char *regs = (void *)sh2->peri_regs;
struct dmac *dmac = (void *)(regs + 0x180);
int level = PREG8(regs, 0xe2) & 0x0f; // IPRA
int vector = (chan == &dmac->chan[0]) ?
dmac->vcrdma0 : dmac->vcrdma1;
elprintf(EL_32XP, "dmac irq %d %d", level, vector);
sh2_internal_irq(sh2, level, vector & 0x7f);
}
static void dmac_transfer_complete(SH2 *sh2, struct dma_chan *chan)
{
chan->chcr |= DMA_TE; // DMA has ended normally
p32x_sh2_poll_event(sh2, SH2_STATE_SLEEP, SekCyclesDoneT());
if (chan->chcr & DMA_IE)
dmac_te_irq(sh2, chan);
}
static void dmac_transfer_one(SH2 *sh2, struct dma_chan *chan)
{
u32 size, d;
size = (chan->chcr >> 10) & 3;
switch (size) {
case 0:
d = p32x_sh2_read8(chan->sar, sh2);
p32x_sh2_write8(chan->dar, d, sh2);
case 1:
d = p32x_sh2_read16(chan->sar, sh2);
p32x_sh2_write16(chan->dar, d, sh2);
break;
case 2:
d = p32x_sh2_read32(chan->sar, sh2);
p32x_sh2_write32(chan->dar, d, sh2);
break;
case 3:
d = p32x_sh2_read32(chan->sar + 0x00, sh2);
p32x_sh2_write32(chan->dar + 0x00, d, sh2);
d = p32x_sh2_read32(chan->sar + 0x04, sh2);
p32x_sh2_write32(chan->dar + 0x04, d, sh2);
d = p32x_sh2_read32(chan->sar + 0x08, sh2);
p32x_sh2_write32(chan->dar + 0x08, d, sh2);
d = p32x_sh2_read32(chan->sar + 0x0c, sh2);
p32x_sh2_write32(chan->dar + 0x0c, d, sh2);
chan->sar += 16; // always?
if (chan->chcr & (1 << 15))
chan->dar -= 16;
if (chan->chcr & (1 << 14))
chan->dar += 16;
chan->tcr -= 4;
return;
}
chan->tcr--;
size = 1 << size;
if (chan->chcr & (1 << 15))
chan->dar -= size;
if (chan->chcr & (1 << 14))
chan->dar += size;
if (chan->chcr & (1 << 13))
chan->sar -= size;
if (chan->chcr & (1 << 12))
chan->sar += size;
}
// DMA trigger by SH2 register write
static void dmac_trigger(SH2 *sh2, struct dma_chan *chan)
{
elprintf(EL_32XP, "sh2 DMA %08x->%08x, cnt %d, chcr %04x @%06x",
chan->sar, chan->dar, chan->tcr, chan->chcr, sh2->pc);
chan->tcr &= 0xffffff;
if (chan->chcr & DMA_AR) {
// auto-request transfer
while ((int)chan->tcr > 0)
dmac_transfer_one(sh2, chan);
dmac_transfer_complete(sh2, chan);
return;
}
// DREQ0 is only sent after first 4 words are written.
// we do multiple of 4 words to avoid messing up alignment
if (chan->sar == 0x20004012) {
if (Pico32x.dmac0_fifo_ptr && (Pico32x.dmac0_fifo_ptr & 3) == 0) {
elprintf(EL_32XP, "68k -> sh2 DMA");
p32x_dreq0_trigger();
}
return;
}
elprintf(EL_32XP|EL_ANOMALY, "unhandled DMA: "
"%08x->%08x, cnt %d, chcr %04x @%06x",
chan->sar, chan->dar, chan->tcr, chan->chcr, sh2->pc);
}
// timer state - FIXME
static int timer_cycles[2];
static int timer_tick_cycles[2];
// timers
void p32x_timers_recalc(void)
{
int cycles;
int tmp, i;
// SH2 timer step
for (i = 0; i < 2; i++) {
tmp = PREG8(sh2s[i].peri_regs, 0x80) & 7;
// Sclk cycles per timer tick
if (tmp)
cycles = 0x20 << tmp;
else
cycles = 2;
timer_tick_cycles[i] = cycles;
timer_cycles[i] = 0;
elprintf(EL_32XP, "WDT cycles[%d] = %d", i, cycles);
}
}
void p32x_timers_do(unsigned int m68k_slice)
{
unsigned int cycles = m68k_slice * 3;
int cnt, i;
// WDT timers
for (i = 0; i < 2; i++) {
void *pregs = sh2s[i].peri_regs;
if (PREG8(pregs, 0x80) & 0x20) { // TME
timer_cycles[i] += cycles;
cnt = PREG8(pregs, 0x81);
while (timer_cycles[i] >= timer_tick_cycles[i]) {
timer_cycles[i] -= timer_tick_cycles[i];
cnt++;
}
if (cnt >= 0x100) {
int level = PREG8(pregs, 0xe3) >> 4;
int vector = PREG8(pregs, 0xe4) & 0x7f;
elprintf(EL_32XP, "%csh2 WDT irq (%d, %d)",
i ? 's' : 'm', level, vector);
sh2_internal_irq(&sh2s[i], level, vector);
cnt &= 0xff;
}
PREG8(pregs, 0x81) = cnt;
}
}
}
void sh2_peripheral_reset(SH2 *sh2)
{
memset(sh2->peri_regs, 0, sizeof(sh2->peri_regs)); // ?
PREG8(sh2->peri_regs, 4) = 0x84; // SCI SSR
}
// ------------------------------------------------------------------
// SH2 internal peripheral memhandlers
// we keep them in little endian format
u32 sh2_peripheral_read8(u32 a, SH2 *sh2)
{
u8 *r = (void *)sh2->peri_regs;
u32 d;
a &= 0x1ff;
d = PREG8(r, a);
elprintf(EL_32XP, "%csh2 peri r8 [%08x] %02x @%06x",
sh2->is_slave ? 's' : 'm', a | ~0x1ff, d, sh2_pc(sh2));
return d;
}
u32 sh2_peripheral_read16(u32 a, SH2 *sh2)
{
u16 *r = (void *)sh2->peri_regs;
u32 d;
a &= 0x1ff;
d = r[(a / 2) ^ 1];
elprintf(EL_32XP, "%csh2 peri r16 [%08x] %04x @%06x",
sh2->is_slave ? 's' : 'm', a | ~0x1ff, d, sh2_pc(sh2));
return d;
}
u32 sh2_peripheral_read32(u32 a, SH2 *sh2)
{
u32 d;
a &= 0x1fc;
d = sh2->peri_regs[a / 4];
elprintf(EL_32XP, "%csh2 peri r32 [%08x] %08x @%06x",
sh2->is_slave ? 's' : 'm', a | ~0x1ff, d, sh2_pc(sh2));
return d;
}
void REGPARM(3) sh2_peripheral_write8(u32 a, u32 d, SH2 *sh2)
{
u8 *r = (void *)sh2->peri_regs;
elprintf(EL_32XP, "%csh2 peri w8 [%08x] %02x @%06x",
sh2->is_slave ? 's' : 'm', a, d, sh2_pc(sh2));
a &= 0x1ff;
PREG8(r, a) = d;
// X-men SCI hack
if ((a == 2 && (d & 0x20)) || // transmiter enabled
(a == 4 && !(d & 0x80))) { // valid data in TDR
void *oregs = sh2->other_sh2->peri_regs;
if ((PREG8(oregs, 2) & 0x50) == 0x50) { // receiver + irq enabled
int level = PREG8(oregs, 0x60) >> 4;
int vector = PREG8(oregs, 0x63) & 0x7f;
elprintf(EL_32XP, "%csh2 SCI recv irq (%d, %d)",
(sh2->is_slave ^ 1) ? 's' : 'm', level, vector);
sh2_internal_irq(sh2->other_sh2, level, vector);
return;
}
}
}
void REGPARM(3) sh2_peripheral_write16(u32 a, u32 d, SH2 *sh2)
{
u16 *r = (void *)sh2->peri_regs;
elprintf(EL_32XP, "%csh2 peri w16 [%08x] %04x @%06x",
sh2->is_slave ? 's' : 'm', a, d, sh2_pc(sh2));
a &= 0x1ff;
// evil WDT
if (a == 0x80) {
if ((d & 0xff00) == 0xa500) { // WTCSR
PREG8(r, 0x80) = d;
p32x_timers_recalc();
}
if ((d & 0xff00) == 0x5a00) // WTCNT
PREG8(r, 0x81) = d;
return;
}
r[(a / 2) ^ 1] = d;
}
void sh2_peripheral_write32(u32 a, u32 d, SH2 *sh2)
{
u32 *r = sh2->peri_regs;
elprintf(EL_32XP, "%csh2 peri w32 [%08x] %08x @%06x",
sh2->is_slave ? 's' : 'm', a, d, sh2_pc(sh2));
a &= 0x1fc;
r[a / 4] = d;
switch (a) {
// division unit (TODO: verify):
case 0x104: // DVDNT: divident L, starts divide
elprintf(EL_32XP, "%csh2 divide %08x / %08x",
sh2->is_slave ? 's' : 'm', d, r[0x100 / 4]);
if (r[0x100 / 4]) {
signed int divisor = r[0x100 / 4];
r[0x118 / 4] = r[0x110 / 4] = (signed int)d % divisor;
r[0x104 / 4] = r[0x11c / 4] = r[0x114 / 4] = (signed int)d / divisor;
}
else
r[0x110 / 4] = r[0x114 / 4] = r[0x118 / 4] = r[0x11c / 4] = 0; // ?
break;
case 0x114:
elprintf(EL_32XP, "%csh2 divide %08x%08x / %08x @%08x",
sh2->is_slave ? 's' : 'm', r[0x110 / 4], d, r[0x100 / 4], sh2_pc(sh2));
if (r[0x100 / 4]) {
signed long long divident = (signed long long)r[0x110 / 4] << 32 | d;
signed int divisor = r[0x100 / 4];
// XXX: undocumented mirroring to 0x118,0x11c?
r[0x118 / 4] = r[0x110 / 4] = divident % divisor;
divident /= divisor;
r[0x11c / 4] = r[0x114 / 4] = divident;
divident >>= 31;
if ((unsigned long long)divident + 1 > 1) {
//elprintf(EL_32XP, "%csh2 divide overflow! @%08x",
// sh2->is_slave ? 's' : 'm', sh2_pc(sh2));
r[0x11c / 4] = r[0x114 / 4] = divident > 0 ? 0x7fffffff : 0x80000000; // overflow
}
}
else
r[0x110 / 4] = r[0x114 / 4] = r[0x118 / 4] = r[0x11c / 4] = 0; // ?
break;
}
// perhaps starting a DMA?
if (a == 0x1b0 || a == 0x18c || a == 0x19c) {
struct dmac *dmac = (void *)&sh2->peri_regs[0x180 / 4];
if (!(dmac->dmaor & DMA_DME))
return;
if ((dmac->chan[0].chcr & (DMA_TE|DMA_DE)) == DMA_DE)
dmac_trigger(sh2, &dmac->chan[0]);
if ((dmac->chan[1].chcr & (DMA_TE|DMA_DE)) == DMA_DE)
dmac_trigger(sh2, &dmac->chan[1]);
}
}
/* 32X specific */
static void dreq0_do(SH2 *sh2, struct dma_chan *chan)
{
unsigned short *dreqlen = &Pico32x.regs[0x10 / 2];
int i;
// debug/sanity checks
if (chan->tcr != *dreqlen)
elprintf(EL_32XP|EL_ANOMALY, "dreq0: tcr0 and len differ: %d != %d",
chan->tcr, *dreqlen);
// note: DACK is not connected, single addr mode should not be used
if ((chan->chcr & 0x3f08) != 0x0400)
elprintf(EL_32XP|EL_ANOMALY, "dreq0: bad control: %04x", chan->chcr);
if (chan->sar != 0x20004012)
elprintf(EL_32XP|EL_ANOMALY, "dreq0: bad sar?: %08x\n", chan->sar);
// HACK: assume bus is busy and SH2 is halted
sh2->state |= SH2_STATE_SLEEP;
for (i = 0; i < Pico32x.dmac0_fifo_ptr && chan->tcr > 0; i++) {
elprintf(EL_32XP, "dmaw [%08x] %04x, left %d",
chan->dar, Pico32x.dmac_fifo[i], *dreqlen);
p32x_sh2_write16(chan->dar, Pico32x.dmac_fifo[i], sh2);
chan->dar += 2;
chan->tcr--;
(*dreqlen)--;
}
if (Pico32x.dmac0_fifo_ptr != i)
memmove(Pico32x.dmac_fifo, &Pico32x.dmac_fifo[i],
(Pico32x.dmac0_fifo_ptr - i) * 2);
Pico32x.dmac0_fifo_ptr -= i;
Pico32x.regs[6 / 2] &= ~P32XS_FULL;
if (*dreqlen == 0)
Pico32x.regs[6 / 2] &= ~P32XS_68S; // transfer complete
if (chan->tcr == 0)
dmac_transfer_complete(sh2, chan);
else
sh2_end_run(sh2, 16);
}
static void dreq1_do(SH2 *sh2, struct dma_chan *chan)
{
// debug/sanity checks
if ((chan->chcr & 0xc308) != 0x0000)
elprintf(EL_32XP|EL_ANOMALY, "dreq1: bad control: %04x", chan->chcr);
if ((chan->dar & ~0xf) != 0x20004030)
elprintf(EL_32XP|EL_ANOMALY, "dreq1: bad dar?: %08x\n", chan->dar);
dmac_transfer_one(sh2, chan);
if (chan->tcr == 0)
dmac_transfer_complete(sh2, chan);
}
void p32x_dreq0_trigger(void)
{
struct dmac *mdmac = (void *)&msh2.peri_regs[0x180 / 4];
struct dmac *sdmac = (void *)&ssh2.peri_regs[0x180 / 4];
elprintf(EL_32XP, "dreq0_trigger");
if ((mdmac->dmaor & DMA_DME) && (mdmac->chan[0].chcr & 3) == DMA_DE) {
dreq0_do(&msh2, &mdmac->chan[0]);
}
if ((sdmac->dmaor & DMA_DME) && (sdmac->chan[0].chcr & 3) == DMA_DE) {
dreq0_do(&ssh2, &sdmac->chan[0]);
}
}
void p32x_dreq1_trigger(void)
{
struct dmac *mdmac = (void *)&msh2.peri_regs[0x180 / 4];
struct dmac *sdmac = (void *)&ssh2.peri_regs[0x180 / 4];
int hit = 0;
elprintf(EL_32XP, "dreq1_trigger");
if ((mdmac->dmaor & DMA_DME) && (mdmac->chan[1].chcr & 3) == DMA_DE) {
dreq1_do(&msh2, &mdmac->chan[1]);
hit = 1;
}
if ((sdmac->dmaor & DMA_DME) && (sdmac->chan[1].chcr & 3) == DMA_DE) {
dreq1_do(&ssh2, &sdmac->chan[1]);
hit = 1;
}
if (!hit)
elprintf(EL_32XP|EL_ANOMALY, "dreq1: nobody cared");
}
// vim:shiftwidth=2:ts=2:expandtab