libpcsxcore/psxevents.c

   1 #include <stddef.h>
   2 #include <stdio.h>
   3 #include "r3000a.h"
   4 #include "cdrom.h"
   5 #include "psxdma.h"
   6 #include "mdec.h"
   7 #include "psxevents.h"
   8
   9 //#define evprintf printf
  10 #define evprintf(...)
  11
  12 static psxRegisters *cp0TOpsxRegs(psxCP0Regs *cp0)
  13 {
  14 #ifndef LIGHTREC
  15         return (void *)((char *)cp0 - offsetof(psxRegisters, CP0));
  16 #else
  17         // lightrec has it's own cp0
  18         return &psxRegs;
  19 #endif
  20 }
  21
  22 u32 schedule_timeslice(psxRegisters *regs)
  23 {
  24         u32 i, c = regs->cycle;
  25         u32 irqs = regs->interrupt;
  26         s32 min, dif;
  27
  28         min = PSXCLK;
  29         for (i = 0; irqs != 0; i++, irqs >>= 1) {
  30                 if (!(irqs & 1))
  31                         continue;
  32                 dif = regs->event_cycles[i] - c;
  33                 //evprintf("  ev %d\n", dif);
  34                 if (0 < dif && dif < min)
  35                         min = dif;
  36         }
  37         regs->next_interupt = c + min;
  38         return regs->next_interupt;
  39 }
  40
  41 static void irqNoOp() {
  42 }
  43
  44 typedef void (irq_func)();
  45
  46 static irq_func * const irq_funcs[] = {
  47         [PSXINT_SIO]    = sioInterrupt,
  48         [PSXINT_CDR]    = cdrInterrupt,
  49         [PSXINT_CDREAD] = cdrPlayReadInterrupt,
  50         [PSXINT_GPUDMA] = gpuInterrupt,
  51         [PSXINT_MDECOUTDMA] = mdec1Interrupt,
  52         [PSXINT_SPUDMA] = spuInterrupt,
  53         [PSXINT_MDECINDMA] = mdec0Interrupt,
  54         [PSXINT_GPUOTCDMA] = gpuotcInterrupt,
  55         [PSXINT_CDRDMA] = cdrDmaInterrupt,
  56         [PSXINT_NEWDRC_CHECK] = irqNoOp,
  57         [PSXINT_CDRLID] = cdrLidSeekInterrupt,
  58         [PSXINT_IRQ10] = irq10Interrupt,
  59         [PSXINT_SPU_UPDATE] = spuUpdate,
  60         [PSXINT_SPU_IRQ] = spuDelayedIrq,
  61         [PSXINT_RCNT] = psxRcntUpdate,
  62 };
  63
  64 void irq_test(psxCP0Regs *cp0)
  65 {
  66         psxRegisters *regs = cp0TOpsxRegs(cp0);
  67         u32 cycle = regs->cycle;
  68         u32 irq, irq_bits;
  69
  70         for (irq = 0, irq_bits = regs->interrupt; irq_bits != 0; irq++, irq_bits >>= 1) {
  71                 if (!(irq_bits & 1))
  72                         continue;
  73                 if ((s32)(cycle - regs->event_cycles[irq]) >= 0) {
  74                         // note: irq_funcs() also modify regs->interrupt
  75                         regs->interrupt &= ~(1u << irq);
  76                         irq_funcs[irq]();
  77                 }
  78         }
  79
  80         cp0->n.Cause &= ~0x400;
  81         if (psxHu32(0x1070) & psxHu32(0x1074))
  82                 cp0->n.Cause |= 0x400;
  83         if (((cp0->n.Cause | 1) & cp0->n.SR & 0x401) == 0x401)
  84                 psxException(0, 0, cp0);
  85 }
  86
  87 void gen_interupt(psxCP0Regs *cp0)
  88 {
  89         psxRegisters *regs = cp0TOpsxRegs(cp0);
  90
  91         evprintf("  +ge %08x, %u->%u (%d)\n", regs->pc, regs->cycle,
  92                 regs->next_interupt, regs->next_interupt - regs->cycle);
  93
  94         irq_test(cp0);
  95         schedule_timeslice(regs);
  96
  97         evprintf("  -ge %08x, %u->%u (%d)\n", regs->pc, regs->cycle,
  98                 regs->next_interupt, regs->next_interupt - regs->cycle);
  99 }
 100
 101 void events_restore(void)
 102 {
 103         int i;
 104         for (i = 0; i < PSXINT_COUNT; i++)
 105                 psxRegs.event_cycles[i] = psxRegs.intCycle[i].sCycle + psxRegs.intCycle[i].cycle;
 106
 107         psxRegs.event_cycles[PSXINT_RCNT] = psxRegs.psxNextsCounter + psxRegs.psxNextCounter;
 108         psxRegs.interrupt |=  1 << PSXINT_RCNT;
 109         psxRegs.interrupt &= (1 << PSXINT_COUNT) - 1;
 110 }