| 1 | // This is part of Pico Library |
| 2 | |
| 3 | // (c) Copyright 2004 Dave, All rights reserved. |
| 4 | // (c) Copyright 2006 notaz, All rights reserved. |
| 5 | // Free for non-commercial use. |
| 6 | |
| 7 | // For commercial use, separate licencing terms must be obtained. |
| 8 | |
| 9 | |
| 10 | #include "../PicoInt.h" |
| 11 | |
| 12 | |
| 13 | int SekCycleCntS68k=0; // cycles done in this frame |
| 14 | int SekCycleAimS68k=0; // cycle aim |
| 15 | |
| 16 | #ifdef EMU_C68K |
| 17 | // ---------------------- Cyclone 68000 ---------------------- |
| 18 | struct Cyclone PicoCpuS68k; |
| 19 | #endif |
| 20 | |
| 21 | #ifdef EMU_M68K |
| 22 | // ---------------------- MUSASHI 68000 ---------------------- |
| 23 | m68ki_cpu_core PicoS68kCPU; // Mega CD's CPU |
| 24 | #endif |
| 25 | |
| 26 | static int new_irq_level(int level) |
| 27 | { |
| 28 | int level_new = 0, irqs; |
| 29 | Pico_mcd->m.s68k_pend_ints &= ~(1 << level); |
| 30 | irqs = Pico_mcd->m.s68k_pend_ints; |
| 31 | irqs &= Pico_mcd->s68k_regs[0x33]; |
| 32 | while ((irqs >>= 1)) level_new++; |
| 33 | |
| 34 | return level_new; |
| 35 | } |
| 36 | |
| 37 | #ifdef EMU_M68K |
| 38 | static int SekIntAckS68k(int level) |
| 39 | { |
| 40 | int level_new = new_irq_level(level); |
| 41 | dprintf("s68kACK %i -> %i", level, level_new); |
| 42 | CPU_INT_LEVEL = level_new << 8; |
| 43 | return M68K_INT_ACK_AUTOVECTOR; |
| 44 | } |
| 45 | #endif |
| 46 | |
| 47 | #ifdef EMU_C68K |
| 48 | // interrupt acknowledgment |
| 49 | static void SekIntAckS68k(int level) |
| 50 | { |
| 51 | int level_new = new_irq_level(level); |
| 52 | |
| 53 | dprintf("s68kACK %i -> %i", level, level_new); |
| 54 | PicoCpuS68k.irq = level_new; |
| 55 | } |
| 56 | |
| 57 | static void SekResetAck() |
| 58 | { |
| 59 | dprintf("s68k: Reset encountered @ %06x", SekPcS68k); |
| 60 | } |
| 61 | |
| 62 | static int SekUnrecognizedOpcode() |
| 63 | { |
| 64 | unsigned int pc, op; |
| 65 | pc = SekPcS68k; |
| 66 | op = PicoCpuS68k.read16(pc); |
| 67 | dprintf("Unrecognized Opcode %04x @ %06x", op, pc); |
| 68 | //exit(1); |
| 69 | return 0; |
| 70 | } |
| 71 | #endif |
| 72 | |
| 73 | |
| 74 | |
| 75 | int SekInitS68k() |
| 76 | { |
| 77 | #ifdef EMU_C68K |
| 78 | // CycloneInit(); |
| 79 | memset(&PicoCpuS68k,0,sizeof(PicoCpuS68k)); |
| 80 | PicoCpuS68k.IrqCallback=SekIntAckS68k; |
| 81 | PicoCpuS68k.ResetCallback=SekResetAck; |
| 82 | PicoCpuS68k.UnrecognizedCallback=SekUnrecognizedOpcode; |
| 83 | #endif |
| 84 | #ifdef EMU_M68K |
| 85 | { |
| 86 | // Musashi is not very context friendly.. |
| 87 | void *oldcontext = m68ki_cpu_p; |
| 88 | m68k_set_context(&PicoS68kCPU); |
| 89 | m68k_set_cpu_type(M68K_CPU_TYPE_68000); |
| 90 | m68k_init(); |
| 91 | m68k_set_int_ack_callback(SekIntAckS68k); |
| 92 | // m68k_pulse_reset(); // not yet, memmap is not set up |
| 93 | m68k_set_context(oldcontext); |
| 94 | } |
| 95 | #endif |
| 96 | |
| 97 | return 0; |
| 98 | } |
| 99 | |
| 100 | // Reset the 68000: |
| 101 | int SekResetS68k() |
| 102 | { |
| 103 | if (Pico.rom==NULL) return 1; |
| 104 | |
| 105 | #ifdef EMU_C68K |
| 106 | PicoCpuS68k.stopped=0; |
| 107 | PicoCpuS68k.osp=0; |
| 108 | PicoCpuS68k.srh =0x27; // Supervisor mode |
| 109 | PicoCpuS68k.flags=4; // Z set |
| 110 | PicoCpuS68k.irq=0; |
| 111 | PicoCpuS68k.a[7]=PicoCpuS68k.read32(0); // Stack Pointer |
| 112 | PicoCpuS68k.membase=0; |
| 113 | PicoCpuS68k.pc=PicoCpuS68k.checkpc(PicoCpuS68k.read32(4)); // Program Counter |
| 114 | #endif |
| 115 | #ifdef EMU_M68K |
| 116 | { |
| 117 | void *oldcontext = m68ki_cpu_p; |
| 118 | |
| 119 | m68k_set_context(&PicoS68kCPU); |
| 120 | m68k_pulse_reset(); |
| 121 | m68k_set_context(oldcontext); |
| 122 | } |
| 123 | #endif |
| 124 | |
| 125 | return 0; |
| 126 | } |
| 127 | |
| 128 | int SekInterruptS68k(int irq) |
| 129 | { |
| 130 | int irqs, real_irq = 1; |
| 131 | Pico_mcd->m.s68k_pend_ints |= 1 << irq; |
| 132 | irqs = Pico_mcd->m.s68k_pend_ints >> 1; |
| 133 | while ((irqs >>= 1)) real_irq++; // this is probably only needed for Cyclone |
| 134 | |
| 135 | #ifdef EMU_C68K |
| 136 | PicoCpuS68k.irq=real_irq; |
| 137 | #endif |
| 138 | #ifdef EMU_M68K |
| 139 | void *oldcontext = m68ki_cpu_p; |
| 140 | m68k_set_context(&PicoS68kCPU); |
| 141 | m68k_set_irq(real_irq); // raise irq (gets lowered after taken or must be done in ack) |
| 142 | m68k_set_context(oldcontext); |
| 143 | #endif |
| 144 | return 0; |
| 145 | } |
| 146 | |