Mercurial > repos > blastem
view romdb.c @ 767:ea525f600b1d
SRAM detection from ROM header is no working correctly again
author | Michael Pavone <pavone@retrodev.com> |
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date | Mon, 06 Jul 2015 19:46:46 -0700 |
parents | 1b2f8280ba81 |
children | 2f48a3c187c6 |
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#include <stdlib.h> #include <string.h> #include "config.h" #include "romdb.h" #include "util.h" #include "blastem.h" #define TITLE_START 0x150 #define TITLE_END (TITLE_START+48) #define GAME_ID_OFF 0x183 #define GAME_ID_LEN 8 #define ROM_END 0x1A4 #define RAM_ID 0x1B0 #define RAM_FLAGS 0x1B2 #define RAM_START 0x1B4 #define RAM_END 0x1B8 #define REGION_START 0x1F0 uint16_t read_sram_w(uint32_t address, m68k_context * context) { genesis_context * gen = context->system; address &= gen->save_ram_mask; switch(gen->save_type) { case RAM_FLAG_BOTH: return gen->save_storage[address] << 8 | gen->save_storage[address+1]; case RAM_FLAG_EVEN: return gen->save_storage[address >> 1] << 8 | 0xFF; case RAM_FLAG_ODD: return gen->save_storage[address >> 1] | 0xFF00; } return 0xFFFF;//We should never get here } uint8_t read_sram_b(uint32_t address, m68k_context * context) { genesis_context * gen = context->system; address &= gen->save_ram_mask; switch(gen->save_type) { case RAM_FLAG_BOTH: return gen->save_storage[address]; case RAM_FLAG_EVEN: if (address & 1) { return 0xFF; } else { return gen->save_storage[address >> 1]; } case RAM_FLAG_ODD: if (address & 1) { return gen->save_storage[address >> 1]; } else { return 0xFF; } } return 0xFF;//We should never get here } m68k_context * write_sram_area_w(uint32_t address, m68k_context * context, uint16_t value) { genesis_context * gen = context->system; if ((gen->bank_regs[0] & 0x3) == 1) { address &= gen->save_ram_mask; switch(gen->save_type) { case RAM_FLAG_BOTH: gen->save_storage[address] = value >> 8; gen->save_storage[address+1] = value; break; case RAM_FLAG_EVEN: gen->save_storage[address >> 1] = value >> 8; break; case RAM_FLAG_ODD: gen->save_storage[address >> 1] = value; break; } } return context; } m68k_context * write_sram_area_b(uint32_t address, m68k_context * context, uint8_t value) { genesis_context * gen = context->system; if ((gen->bank_regs[0] & 0x3) == 1) { address &= gen->save_ram_mask; switch(gen->save_type) { case RAM_FLAG_BOTH: gen->save_storage[address] = value; break; case RAM_FLAG_EVEN: if (!(address & 1)) { gen->save_storage[address >> 1] = value; } break; case RAM_FLAG_ODD: if (address & 1) { gen->save_storage[address >> 1] = value; } break; } } return context; } m68k_context * write_bank_reg_w(uint32_t address, m68k_context * context, uint16_t value) { genesis_context * gen = context->system; address &= 0xE; address >>= 1; gen->bank_regs[address] = value; if (!address) { if (value & 1) { context->mem_pointers[2] = NULL; } else { context->mem_pointers[2] = cart + 0x200000/2; } } return context; } m68k_context * write_bank_reg_b(uint32_t address, m68k_context * context, uint8_t value) { if (address & 1) { genesis_context * gen = context->system; address &= 0xE; address >>= 1; gen->bank_regs[address] = value; if (!address) { if (value & 1) { context->mem_pointers[2] = NULL; } else { context->mem_pointers[2] = cart + 0x200000/2; } } } return context; } tern_node *load_rom_db() { char *exe_dir = get_exe_dir(); if (!exe_dir) { fputs("Failed to find executable path\n", stderr); exit(1); } char *path = alloc_concat(exe_dir, "/rom.db"); tern_node *db = parse_config_file(path); free(path); if (!db) { fputs("Failed to load ROM DB\n", stderr); } return db; } char *get_header_name(uint8_t *rom) { uint8_t *last = rom + TITLE_END - 1; uint8_t *src = rom + TITLE_START; while (last > src && (*last <= 0x20 || *last >= 0x80)) { last--; } if (last == src) { //TODO: Use other name field return strdup("UNKNOWN"); } else { last++; char *ret = malloc(last - (rom + TITLE_START) + 1); uint8_t *dst; for (dst = ret; src < last; src++) { if (*src >= 0x20 && *src < 0x80) { *(dst++) = *src; } } *dst = 0; return ret; } } char *region_chars = "UB4JEA"; uint8_t region_bits[] = {REGION_U, REGION_U, REGION_U, REGION_J, REGION_E, REGION_E}; uint8_t translate_region_char(uint8_t c) { for (int i = 0; i < sizeof(region_bits); i++) { if (c == region_chars[i]) { return region_bits[i]; } } return 0; } uint8_t get_header_regions(uint8_t *rom) { uint8_t regions = 0; for (int i = 0; i < 3; i++) { regions |= translate_region_char(rom[REGION_START + i]); } return regions; } uint32_t get_u32be(uint8_t *data) { return *data << 24 | data[1] << 16 | data[2] << 8 | data[3]; } void add_memmap_header(rom_info *info, uint8_t *rom, uint32_t size, memmap_chunk const *base_map, int base_chunks) { if (rom[RAM_ID] == 'R' && rom[RAM_ID+1] == 'A') { uint32_t rom_end = get_u32be(rom + ROM_END) + 1; uint32_t ram_start = get_u32be(rom + RAM_START); uint32_t ram_end = get_u32be(rom + RAM_END); uint32_t ram_flags = info->save_type = rom[RAM_FLAGS] & RAM_FLAG_MASK; ram_start &= 0xFFFFFE; ram_end |= 1; info->save_mask = ram_end - ram_start; uint32_t size = info->save_mask + 1; if (ram_flags != RAM_FLAG_BOTH) { size /= 2; } info->save_size = size; info->save_buffer = malloc(size); info->map_chunks = base_chunks + (ram_start >= rom_end ? 2 : 3); info->map = malloc(sizeof(memmap_chunk) * info->map_chunks); memset(info->map, 0, sizeof(memmap_chunk)*2); memcpy(info->map+2, base_map, sizeof(memmap_chunk) * base_chunks); if (ram_start >= rom_end) { info->map[0].end = rom_end; //TODO: ROM mirroring info->map[0].mask = 0xFFFFFF; info->map[0].flags = MMAP_READ; info->map[0].buffer = rom; info->map[1].start = ram_start; info->map[1].mask = info->save_mask; info->map[1].end = ram_end + 1; info->map[1].flags = MMAP_READ | MMAP_WRITE; if (ram_flags == RAM_FLAG_ODD) { info->map[1].flags |= MMAP_ONLY_ODD; } else if (ram_flags == RAM_FLAG_EVEN) { info->map[1].flags |= MMAP_ONLY_EVEN; } info->map[1].buffer = info->save_buffer; } else { //Assume the standard Sega mapper info->map[0].end = 0x200000; info->map[0].mask = 0xFFFFFF; info->map[0].flags = MMAP_READ; info->map[0].buffer = rom; info->map[1].start = 0x200000; info->map[1].end = 0x400000; info->map[1].mask = 0x1FFFFF; info->map[1].flags = MMAP_READ | MMAP_PTR_IDX | MMAP_FUNC_NULL; info->map[1].ptr_index = 2; info->map[1].read_16 = (read_16_fun)read_sram_w;//these will only be called when mem_pointers[2] == NULL info->map[1].read_8 = (read_8_fun)read_sram_b; info->map[1].write_16 = (write_16_fun)write_sram_area_w;//these will be called all writes to the area info->map[1].write_8 = (write_8_fun)write_sram_area_b; info->map[1].buffer = cart + 0x200000; memmap_chunk *last = info->map + info->map_chunks - 1; memset(last, 0, sizeof(memmap_chunk)); last->start = 0xA13000; last->end = 0xA13100; last->mask = 0xFF; last->write_16 = (write_16_fun)write_bank_reg_w; last->write_8 = (write_8_fun)write_bank_reg_b; } } else { info->map_chunks = base_chunks + 1; info->map = malloc(sizeof(memmap_chunk) * info->map_chunks); memset(info->map, 0, sizeof(memmap_chunk)); memcpy(info->map+1, base_map, sizeof(memmap_chunk) * base_chunks); info->map[0].end = 0x400000; info->map[0].mask = 0xFFFFFF; info->map[0].flags = MMAP_READ; info->map[0].buffer = rom; info->save_type = SAVE_NONE; } } rom_info configure_rom_heuristics(uint8_t *rom, uint32_t rom_size, memmap_chunk const *base_map, uint32_t base_chunks) { rom_info info; info.name = get_header_name(rom); info.regions = get_header_regions(rom); add_memmap_header(&info, rom, rom_size, base_map, base_chunks); return info; } rom_info configure_rom(tern_node *rom_db, void *vrom, uint32_t rom_size, memmap_chunk const *base_map, uint32_t base_chunks) { uint8_t product_id[GAME_ID_LEN+1]; uint8_t *rom = vrom; product_id[GAME_ID_LEN] = 0; for (int i = 0; i < GAME_ID_LEN; i++) { if (rom[GAME_ID_OFF + i] <= ' ') { product_id[i] = 0; break; } product_id[i] = rom[GAME_ID_OFF + i]; } tern_node * entry = tern_find_prefix(rom_db, product_id); if (!entry) { return configure_rom_heuristics(rom, rom_size, base_map, base_chunks); } rom_info info; info.name = tern_find_ptr(entry, "name"); if (info.name) { info.name = strdup(info.name); } else { info.name = get_header_name(rom); } char *dbreg = tern_find_ptr(entry, "regions"); info.regions = 0; if (dbreg) { while (*dbreg != 0) { info.regions |= translate_region_char(*(dbreg++)); } } if (!info.regions) { info.regions = get_header_regions(rom); } tern_node *map = tern_find_prefix(entry, "map"); if (map) { uint32_t map_count = tern_count(map); if (map_count) { } else { add_memmap_header(&info, rom, rom_size, base_map, base_chunks); } } else { add_memmap_header(&info, rom, rom_size, base_map, base_chunks); } return info; }