+/*
+ * 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 *)Pico32xMem->sh2_peri_regs[sh2->is_slave];
+ 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(Pico32xMem->sh2_peri_regs[i], 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 = Pico32xMem->sh2_peri_regs[i];
+ 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;
+ }
+ }
+}
+
+// ------------------------------------------------------------------
+// SH2 internal peripheral memhandlers
+// we keep them in little endian format
+
+u32 sh2_peripheral_read8(u32 a, int id)
+{
+ u8 *r = (void *)Pico32xMem->sh2_peri_regs[id];
+ u32 d;
+
+ a &= 0x1ff;
+ d = PREG8(r, a);
+
+ elprintf(EL_32XP, "%csh2 peri r8 [%08x] %02x @%06x", id ? 's' : 'm', a | ~0x1ff, d, sh2_pc(id));
+ return d;
+}
+
+u32 sh2_peripheral_read16(u32 a, int id)
+{
+ u16 *r = (void *)Pico32xMem->sh2_peri_regs[id];
+ u32 d;
+
+ a &= 0x1ff;
+ d = r[(a / 2) ^ 1];
+
+ elprintf(EL_32XP, "%csh2 peri r16 [%08x] %04x @%06x", id ? 's' : 'm', a | ~0x1ff, d, sh2_pc(id));
+ return d;
+}
+
+u32 sh2_peripheral_read32(u32 a, int id)
+{
+ u32 d;
+ a &= 0x1fc;
+ d = Pico32xMem->sh2_peri_regs[id][a / 4];
+
+ elprintf(EL_32XP, "%csh2 peri r32 [%08x] %08x @%06x", id ? 's' : 'm', a | ~0x1ff, d, sh2_pc(id));
+ return d;
+}
+
+int REGPARM(3) sh2_peripheral_write8(u32 a, u32 d, int id)
+{
+ u8 *r = (void *)Pico32xMem->sh2_peri_regs[id];
+ elprintf(EL_32XP, "%csh2 peri w8 [%08x] %02x @%06x", id ? 's' : 'm', a, d, sh2_pc(id));
+
+ 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 = Pico32xMem->sh2_peri_regs[id ^ 1];
+ 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)", (id ^ 1) ? 's' : 'm', level, vector);
+ sh2_internal_irq(&sh2s[id ^ 1], level, vector);
+ return 1;
+ }
+ }
+ return 0;
+}
+
+int REGPARM(3) sh2_peripheral_write16(u32 a, u32 d, int id)
+{
+ u16 *r = (void *)Pico32xMem->sh2_peri_regs[id];
+ elprintf(EL_32XP, "%csh2 peri w16 [%08x] %04x @%06x", id ? 's' : 'm', a, d, sh2_pc(id));
+
+ 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 0;
+ }
+
+ r[(a / 2) ^ 1] = d;
+ return 0;
+}
+
+void sh2_peripheral_write32(u32 a, u32 d, int id)
+{
+ u32 *r = Pico32xMem->sh2_peri_regs[id];
+ elprintf(EL_32XP, "%csh2 peri w32 [%08x] %08x @%06x", id ? 's' : 'm', a, d, sh2_pc(id));
+
+ 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", id ? '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",
+ id ? 's' : 'm', r[0x110 / 4], d, r[0x100 / 4], sh2_pc(id));
+ 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", id ? 's' : 'm', sh2_pc(id));
+ 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 *)&Pico32xMem->sh2_peri_regs[id][0x180 / 4];
+ if (!(dmac->dmaor & DMA_DME))
+ return;
+
+ if ((dmac->chan[0].chcr & (DMA_TE|DMA_DE)) == DMA_DE)
+ dmac_trigger(&sh2s[id], &dmac->chan[0]);
+ if ((dmac->chan[1].chcr & (DMA_TE|DMA_DE)) == DMA_DE)
+ dmac_trigger(&sh2s[id], &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 *)&Pico32xMem->sh2_peri_regs[0][0x180 / 4];
+ struct dmac *sdmac = (void *)&Pico32xMem->sh2_peri_regs[1][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 *)&Pico32xMem->sh2_peri_regs[0][0x180 / 4];
+ struct dmac *sdmac = (void *)&Pico32xMem->sh2_peri_regs[1][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