libpcsxcore/psxevents.c

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