Mercurial > repos > blastem
view realtec.c @ 1374:8f404b1fa572
Go back to resetting the refresh counter after a DMA. Probably not quite correct as it is probably reset on VDP triggered refresh, but this is close enough for now given the general limitations with my refresh code. VDP FIFO Testing seems to be passing 100% reliably again (was occassionally failing still with the last commit)
author | Michael Pavone <pavone@retrodev.com> |
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date | Tue, 23 May 2017 23:47:40 -0700 |
parents | f13f51e9f9f2 |
children | 11ac0b511cff |
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#include <stdint.h> #include <stdlib.h> #include <string.h> #include "romdb.h" #include "genesis.h" #include "util.h" typedef struct { uint8_t rom_space[512*1024]; uint8_t regs[3]; } realtec; uint8_t realtec_detect(uint8_t *rom, uint32_t rom_size) { //All Realtec mapper games are 512KB total if (rom_size != 512*1024) { return 0; } return memcmp(rom + 0x7E100, "SEGA", 4) == 0; } static void *realtec_write_b(uint32_t address, void *context, uint8_t value) { if (address & 1) { return context; } m68k_context *m68k = context; genesis_context *gen = m68k->system; if (!gen->extra) { gen->extra = m68k->mem_pointers[0]; } realtec *r = gen->extra; uint32_t offset = address >> 13; uint8_t dirty = 0; if (offset < 3 && r->regs[offset] != value) { r->regs[offset] = value; //other regs are only 3 bits, so assume 3 for this one too uint32_t size = (r->regs[1] & 0x7) << 17; uint32_t start = (r->regs[2] & 7) << 17 | (r->regs[0] & 6) << 19; if (size > 512*1024) { size = 512*1024; } for(uint32_t cur = 0; cur < 512*1024; cur += size) { if (start + size > 512*1024) { memcpy(r->rom_space + cur, gen->cart + start/2, 512*1024-start); //assume it wraps memcpy(r->rom_space + cur + 512*1024-start, gen->cart, size - (512*1024-start)); } else { memcpy(r->rom_space + cur, gen->cart + start/2, size); } } m68k_invalidate_code_range(gen->m68k, 0, 0x400000); } return context; } static void *realtec_write_w(uint32_t address, void *context, uint16_t value) { return realtec_write_b(address, context, value >> 8); } rom_info realtec_configure_rom(uint8_t *rom, uint32_t rom_size, memmap_chunk const *base_map, uint32_t base_chunks) { rom_info info; realtec *r = calloc(sizeof(realtec), 1); for (uint32_t i = 0; i < 512*1024; i += 8*1024) { memcpy(r->rom_space + i, rom + 0x7E000, 8*1024); } byteswap_rom(512*1024, (uint16_t *)r->rom_space); uint8_t *name_start = NULL, *name_end = NULL; for (int i = 0x94; i < 0xE0; i++) { if (name_start) { if (rom[i] < ' ' || rom[i] > 0x80 || !memcmp(rom+i, "ARE", 3) || !memcmp(rom+i, "are", 3)) { name_end = rom+i; break; } } else if (rom[i] > ' ' && rom[i] < 0x80 && rom[i] != ':') { name_start = rom + i; } } if (name_start && !name_end) { name_end = rom + 0xE0; } if (name_end) { while (name_end > name_start && name_end[-1] == ' ') { name_end--; } info.name = malloc(name_end-name_start+1); memcpy(info.name, name_start, name_end-name_start); info.name[name_end-name_start] = 0; } else { info.name = strdup("Realtec Game"); } info.save_type = SAVE_NONE; info.save_size = 0; info.save_buffer = NULL; info.num_eeprom = 0; info.eeprom_map = NULL; info.port1_override = info.port2_override = info.ext_override = info.mouse_mode = NULL; info.map_chunks = base_chunks + 2; info.map = calloc(sizeof(memmap_chunk), info.map_chunks); info.map[0].mask = sizeof(r->rom_space)-1; info.map[0].flags = MMAP_READ|MMAP_CODE|MMAP_PTR_IDX; info.map[0].start = 0; info.map[0].end = 0x400000; info.map[0].buffer = r->rom_space; info.map[0].write_16 = NULL; info.map[0].read_16 = NULL; info.map[0].write_8 = NULL; info.map[0].read_8 = NULL; info.map[1].mask = 0x7FFF; info.map[1].flags = 0; info.map[1].start = 0x400000; info.map[1].end = 0x800000; info.map[1].write_16 = realtec_write_w; info.map[1].write_8 = realtec_write_b; info.map[1].read_16 = NULL; info.map[1].read_8 = NULL; memcpy(info.map + 2, base_map, base_chunks * sizeof(memmap_chunk)); return info; }