diff options
Diffstat (limited to 'trunk/src/emu/cpu/scudsp/scudspdasm.c')
-rw-r--r-- | trunk/src/emu/cpu/scudsp/scudspdasm.c | 343 |
1 files changed, 343 insertions, 0 deletions
diff --git a/trunk/src/emu/cpu/scudsp/scudspdasm.c b/trunk/src/emu/cpu/scudsp/scudspdasm.c new file mode 100644 index 00000000000..b696f99f392 --- /dev/null +++ b/trunk/src/emu/cpu/scudsp/scudspdasm.c @@ -0,0 +1,343 @@ +/* + Sega Saturn SCU DSP disassembler + + Written by Angelo Salese +*/ + +#include "emu.h" + +enum +{ + EA_A = 1, + EA_ALU, + EA_D0, + EA_IMM8, + EA_IMM18, + EA_IMM25, + EA_MUL, + EA_P, + EA_X, + EA_Y, + EA_SRCMEMX, + EA_SRCMEMY, + EA_SRCMEMD1, + EA_DMADSTMEM, + EA_DSTMEM, + EA_MVIDSTMEM, +}; + +typedef struct { + char mnemonic[32]; + int address_mode_1; + int address_mode_2; + int address_mode_3, +} SCUDSP_OPCODE; + +static const SCUDSP_OPCODE alu_table[16] = +{ + { "NOP", 0, 0, 0, }, /* 0000 */ + { "AND", 0, 0, 0, }, /* 0001 */ + { "OR ", 0, 0, 0, }, /* 0010 */ + { "XOR", 0, 0, 0, }, /* 0011 */ + { "ADD", 0, 0, 0, }, /* 0100 */ + { "SUB", 0, 0, 0, }, /* 0101 */ + { "AD2", 0, 0, 0, }, /* 0110 */ + { "???", 0, 0, 0, }, /* 0111 */ + { "SR ", 0, 0, 0, }, /* 1000 */ + { "RR ", 0, 0, 0, }, /* 1001 */ + { "SL ", 0, 0, 0, }, /* 1010 */ + { "RL ", 0, 0, 0, }, /* 1011 */ + { "???", 0, 0, 0, }, /* 1100 */ + { "???", 0, 0, 0, }, /* 1101 */ + { "???", 0, 0, 0, }, /* 1110 */ + { "RL8", 0, 0, 0, }, /* 1111 */ +}; + +static const SCUDSP_OPCODE xbus_table[] = +{ + { "NOP", 0, 0, 0, }, /* 000 */ + { "???", 0, 0, 0, }, /* 001 */ + { "MOV", EA_MUL, EA_P, 0, }, /* 010 */ + { "MOV", EA_SRCMEMX, EA_P, 0, }, /* 011 */ //MOV %s,P + { "MOV", EA_SRCMEMX, EA_X, 0, }, /* 100 */ //MOV %s,X + { "???", 0, 0, 0, }, /* 101 */ + { "???", 0, 0, 0, }, /* 110 */ + { "???", 0, 0, 0, }, /* 111 */ +}; + +static const SCUDSP_OPCODE ybus_table[] = +{ + { "NOP", 0, 0, 0, }, /* 000 */ + { "CLR", 0, EA_A, 0, }, /* 001 */ + { "MOV", EA_ALU, EA_A, 0, }, /* 010 */ + { "MOV", EA_SRCMEMY, EA_A, 0, }, /* 011 */ //MOV %s,A + { "MOV", EA_SRCMEMY, EA_Y, 0, }, /* 100 */ //MOV %s,Y + { "???", 0, 0, 0, }, /* 101 */ + { "???", 0, 0, 0, }, /* 110 */ + { "???", 0, 0, 0, }, /* 111 */ +}; + +static const SCUDSP_OPCODE d1bus_table[] = +{ + { "NOP", 0, 0, 0, }, /* 00 */ + { "MOV", EA_IMM8, EA_DSTMEM, 0, }, /* 01 */ //MOV %I8,%d + { "???", 0, 0, 0, }, /* 10 */ + { "MOV", EA_SRCMEMD1,0, 0, }, /* 11 */ //MOV %S,%d +}; + +static const SCUDSP_OPCODE mvi_table[] = +{ + { "MVI", EA_IMM25, EA_MVIDSTMEM, 0, }, /* 0 */ //"MVI %I,%d" + { "MVI", EA_IMM18, EA_MVIDSTMEM, EA_FLAGS, }, /* 1 */ //"MVI %I,%d,%f" +}; + +static const SCUDSP_OPCODE dma_table[] = +{ + { "DMA", EA_D0, EA_DMADSTMEM, EA_IMM8, }, /* 000 */ // "DMA%H%A D0,%M,%I", + { "DMA", EA_DMASRCMEM, EA_D0, EA_IMM8, }, /* 001 */ // "DMA%H%A %s,D0,%I", + { "DMA", 0, 0, 0, }, /* 010 */ // "DMA%H%A D0,%M,%s", + { "DMA", 0, 0, 0, }, /* 011 */ // "DMA%H%A %s,D0,%s", + { "DMAH", EA_D0, EA_DMADSTMEM, EA_IMM8, }, /* 100 */ // "DMA%H%A D0,%M,%I", + { "DMAH", EA_DMASRCMEM, EA_D0, EA_IMM8, }, /* 101 */ // "DMA%H%A %s,D0,%I", + { "DMAH", 0, 0, 0, }, /* 110 */ // "DMA%H%A D0,%M,%s", + { "DMAH", 0, 0, 0, }, /* 111 */ // "DMA%H%A %s,D0,%s", + +}; + +static const SCUDSP_OPCODE jmp_table[] = +{ + { "JMP", EA_IMM8, 0, 0, }, /* 0 */ // unconditional + { "JMP", EA_IMM8, 0, EA_FLAGS, }, /* 1 */ // conditional +}; + +static const SCUDSP_OPCODE loop_table[] = +{ + { "BTM", 0, 0, 0, }, /* 00 */ + { "LPS", 0, 0, 0, }, /* 01 */ +}; + +static const SCUDSP_OPCODE end_table[] = +{ + { "END", 0, 0, 0, }, /* 00 */ + { "ENDI",0, 0, 0, }, /* 01 */ +}; + + +static const char *const src_mem[] = +{ + "M0", /* 0000 */ + "M1", /* 0001 */ + "M2", /* 0010 */ + "M3", /* 0011 */ + "MC0", /* 0100 */ + "MC1", /* 0101 */ + "MC2", /* 0110 */ + "MC3", /* 0111 */ + "???", /* 1000 */ + "ALL", /* 1001 */ + "ALH", /* 1010 */ + "???", /* 1011 */ + "???", /* 1100 */ + "???", /* 1101 */ + "???", /* 1110 */ + "???", /* 1111 */ +}; + +static const char *const dst_mem[] = +{ + "MC0", /* 0000 */ + "MC1", /* 0001 */ + "MC2", /* 0010 */ + "MC3", /* 0011 */ + "RX", /* 0100 */ + "PL", /* 0101 */ + "RA0", /* 0110 */ + "WA0", /* 0111 */ + "???", /* 1000 */ + "???", /* 1001 */ + "LOP", /* 1010 */ + "TOP", /* 1011 */ + "CT0", /* 1100 */ + "CT1", /* 1101 */ + "CT2", /* 1110 */ + "CT3", /* 1111 */ +}; + +static const char *const mvi_dst_mem[] = +{ + "MC0", /* 0000 */ + "MC1", /* 0001 */ + "MC2", /* 0010 */ + "MC3", /* 0011 */ + "RX", /* 0100 */ + "PL", /* 0101 */ + "RA0", /* 0110 */ + "WA0", /* 0111 */ + "???", /* 1000 */ + "???", /* 1001 */ + "LOP", /* 1010 */ + "???", /* 1011 */ + "PC", /* 1100 */ //??? + "???", /* 1101 */ + "???", /* 1110 */ + "???", /* 1111 */ +}; + +static const char *const cond_flags[] = +{ + "??", /* 0000 */ + "Z ", /* 0001 */ + "S ", /* 0010 */ + "ZS", /* 0011 */ + "C ", /* 0100 */ + "??", /* 0101 */ + "??", /* 0110 */ + "??", /* 0111 */ + "T0", /* 1000 */ + "??", /* 1001 */ + "??", /* 1010 */ + "??", /* 1011 */ + "??", /* 1100 */ + "??", /* 1101 */ + "??", /* 1110 */ + "??", /* 1111 */ +}; + +/*****************************************************************************/ + +static char *output; +static const UINT32 *rombase; + +static void ATTR_PRINTF(1,2) print(const char *fmt, ...) +{ + va_list vl; + + va_start(vl, fmt); + output += vsprintf(output, fmt, vl); + va_end(vl); +} + +static UINT32 fetch(void) +{ + return *rombase++; +} + +static UINT8 add_table(UINT32 cur_opcode) +{ + UINT8 res = (cur_opcode & 0x00038000) >> 15; + + if(res == 0) + res = 0; + else + res = 1 << (res-1); + + return res; +} + +static UINT32 decode_opcode(UINT32 pc, const SCUDSP_OPCODE *op_table,UINT32 cur_opcode) +{ + INT8 rel8; + UINT32 imm32; + UINT8 op2; + UINT32 flags = 0; + + //if (!strcmp(op_table->mnemonic, "jsr") || !strcmp(op_table->mnemonic, "bsr")) + // flags = DASMFLAG_STEP_OVER; + //else if (!strcmp(op_table->mnemonic, "rts") || !strcmp(op_table->mnemonic, "rti")) + // flags = DASMFLAG_STEP_OUT; + + print("%s ", op_table->mnemonic); + + switch(op_table->address_mode_1) + { + case EA_ALU: print("ALU "); break; + case EA_IMM8: print("%02X ",cur_opcode & 0xff); break; + case EA_IMM18: print("%08X ",cur_opcode & 0x7ffff); break; + case EA_IMM25: print("%08X ",cur_opcode & 0x1ffffff); break; + case EA_MUL: print("MUL "); break; + case EA_SRCMEMX: print("%s ", src_mem[(cur_opcode & 0x00700000) >> 20]); break; + case EA_SRCMEMY: print("%s ", src_mem[(cur_opcode & 0x0001c000) >> 14]); break; + case EA_SRCMEMD1: print("%s ", src_mem[(cur_opcode & 0x0000000f) >> 0]); break; + case EA_D0: print("%d D0 ",add_table(cur_opcode)); break; + case EA_DMASRCMEM: print("%d %s ",add_table(cur_opcode),src_mem[(cur_opcode & 0x00000300) >> 8]); break; + + default: + break; + } + + switch(op_table->address_mode_2) + { + case EA_A: print("A"); break; + case EA_P: print("P"); break; + case EA_X: print("X"); break; + case EA_Y: print("Y"); break; + case EA_DSTMEM: print("%s ", dst_mem[(cur_opcode & 0x00000f00) >> 8]); break; + case EA_DMADSTMEM: print("%s ", dst_mem[(cur_opcode & 0x00000300) >> 8]); break; + case EA_MVIDSTMEM: print("%s ", mvi_dst_mem[(cur_opcode & 0x3c000000) >> 26]); break; + case EA_D0: print("D0 "); break; + + default: + break; + } + + switch(op_table->address_mode_3) + { + case EA_IMM8: print("%02X ",cur_opcode & 0xff); break; + case EA_FLAGS: + if(!((cur_opcode >> 19) & 0x20)) + print("N"); + print("%s ", cond_flags[(cur_opcode & 0x0780000) >> 19]); + break; + + default: + break; + } + + return flags; +} + +CPU_DISASSEMBLE( scudsp ) +{ + UINT32 flags = 0; + UINT8 opcode; + + output = buffer; + rombase = oprom; + + opcode = fetch(); + switch((opcode & 0xc0000000) >> 30) + { + case 0: // operation + flags = decode_opcode(pc, &alu_table [(opcode & 0x3c000000) >> 26],opcode); + flags |= decode_opcode(pc, &xbus_table [(opcode & 0x03800000) >> 23],opcode); + flags |= decode_opcode(pc, &ybus_table [(opcode & 0x000e0000) >> 17],opcode); + flags |= decode_opcode(pc, &d1bus_table[(opcode & 0x00003000) >> 12],opcode); + break; + case 1: // unknown + print("???"); + flags = 0; + break; + case 2: // move immediate + flags = decode_opcode(pc, &mvi_table [(opcode & 0x02000000) >> 25],opcode); + break; + case 3: // control + switch((opcode & 0x30000000) >> 28) + { + case 0: + flags = decode_opcode(pc, &dma_table [(opcode & 0x7000) >> 12],opcode); + break; + case 1: + flags = decode_opcode(pc, &jmp_table [(opcode & 0x2000000) >> 25],opcode); + break; + case 2: + flags = decode_opcode(pc, &loop_table [(opcode & 0x8000000) >> 27],opcode); + break; + case 3: + flags = decode_opcode(pc, &end_table [(opcode & 0x8000000) >> 27],opcode); + break; + } + break; + } + + return (rombase-oprom) | flags | DASMFLAG_SUPPORTED; +} |