/* sd2snes - SD card based universal cartridge for the SNES Copyright (C) 2009-2010 Maximilian Rehkopf AVR firmware portion Inspired by and based on code from sd2iec, written by Ingo Korb et al. See sdcard.c|h, config.h. FAT file system access based on code by ChaN, Jim Brain, Ingo Korb, see ff.c|h. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; version 2 of the License only. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA smc.c: SMC file related operations */ #include "fileops.h" #include "config.h" #include "uart.h" #include "smc.h" #include "string.h" #include "fpga_spi.h" snes_romprops_t romprops; uint32_t hdr_addr[6] = {0xffb0, 0x101b0, 0x7fb0, 0x81b0, 0x40ffb0, 0x4101b0}; uint8_t isFixed( uint8_t *data, int size, uint8_t value ) { uint8_t res = 1; do { size--; if ( data[size] != value ) { res = 0; } } while ( size ); return res; } uint8_t checkChksum( uint16_t cchk, uint16_t chk ) { uint32_t sum = cchk + chk; uint8_t res = 0; if ( sum == 0x0000ffff ) { res = 1; } return res; } void smc_id( snes_romprops_t *props ) { uint8_t score, maxscore = 1, score_idx = 2; /* assume LoROM */ snes_header_t *header = &( props->header ); props->has_dspx = 0; props->has_st0010 = 0; props->has_cx4 = 0; props->fpga_features = 0; props->fpga_conf = NULL; for ( uint8_t num = 0; num < 6; num++ ) { score = smc_headerscore( hdr_addr[num], header ); printf( "%d: offset = %lX; score = %d\n", num, hdr_addr[num], score ); // */ if ( score >= maxscore ) { score_idx = num; maxscore = score; } } if ( score_idx & 1 ) { props->offset = 0x200; } else { props->offset = 0; } /* restore the chosen one */ /*dprintf("winner is %d\n", score_idx); */ file_readblock( header, hdr_addr[score_idx], sizeof( snes_header_t ) ); if ( header->name[0x13] == 0x00 || header->name[0x13] == 0xff ) { if ( header->name[0x14] == 0x00 ) { const uint8_t n15 = header->map; if ( n15 == 0x00 || n15 == 0x80 || n15 == 0x84 || n15 == 0x9c || n15 == 0xbc || n15 == 0xfc ) { if ( header->licensee == 0x33 || header->licensee == 0xff ) { props->mapper_id = 0; /*XXX do this properly */ props->ramsize_bytes = 0x8000; props->romsize_bytes = 0x100000; props->expramsize_bytes = 0; props->mapper_id = 3; /* BS-X Memory Map */ props->region = 0; /* BS-X only existed in Japan */ return; } } } } switch ( header->map & 0xef ) { case 0x21: /* HiROM */ props->mapper_id = 0; if ( header->map == 0x31 && ( header->carttype == 0x03 || header->carttype == 0x05 ) ) { props->has_dspx = 1; props->dsp_fw = DSPFW_1B; props->fpga_features |= FEAT_DSPX; } break; case 0x20: /* LoROM */ props->mapper_id = 1; if ( header->map == 0x20 && header->carttype == 0xf3 ) { props->has_cx4 = 1; props->dsp_fw = CX4FW; props->fpga_conf = FPGA_CX4; props->fpga_features |= FEAT_CX4; } else if ( ( header->map == 0x20 && header->carttype == 0x03 ) || ( header->map == 0x30 && header->carttype == 0x05 && header->licensee != 0xb2 ) ) { props->has_dspx = 1; props->fpga_features |= FEAT_DSPX; /* Pilotwings uses DSP1 instead of DSP1B */ if ( !memcmp( header->name, "PILOTWINGS", 10 ) ) { props->dsp_fw = DSPFW_1; } else { props->dsp_fw = DSPFW_1B; } } else if ( header->map == 0x20 && header->carttype == 0x05 ) { props->has_dspx = 1; props->dsp_fw = DSPFW_2; props->fpga_features |= FEAT_DSPX; } else if ( header->map == 0x30 && header->carttype == 0x05 && header->licensee == 0xb2 ) { props->has_dspx = 1; props->dsp_fw = DSPFW_3; props->fpga_features |= FEAT_DSPX; } else if ( header->map == 0x30 && header->carttype == 0x03 ) { props->has_dspx = 1; props->dsp_fw = DSPFW_4; props->fpga_features |= FEAT_DSPX; } else if ( header->map == 0x30 && header->carttype == 0xf6 && header->romsize >= 0xa ) { props->has_dspx = 1; props->has_st0010 = 1; props->dsp_fw = DSPFW_ST0010; props->fpga_features |= FEAT_ST0010; header->ramsize = 2; } break; case 0x25: /* ExHiROM */ props->mapper_id = 2; break; case 0x22: /* ExLoROM */ if ( file_handle.fsize > 0x400200 ) { props->mapper_id = 6; /* SO96 */ } else { props->mapper_id = 1; } break; default: /* invalid/unsupported mapper, use header location */ switch ( score_idx ) { case 0: case 1: props->mapper_id = 0; break; case 2: case 3: if ( file_handle.fsize > 0x800200 ) { props->mapper_id = 6; /* SO96 interleaved */ } else if ( file_handle.fsize > 0x400200 ) { props->mapper_id = 1; /* ExLoROM */ } else { props->mapper_id = 1; /* LoROM */ } break; case 4: case 5: props->mapper_id = 2; break; default: props->mapper_id = 1; // whatever } } if ( header->romsize == 0 || header->romsize > 13 ) { props->romsize_bytes = 1024; header->romsize = 0; if ( file_handle.fsize >= 1024 ) { while ( props->romsize_bytes < file_handle.fsize - 1 ) { header->romsize++; props->romsize_bytes <<= 1; } } } props->ramsize_bytes = ( uint32_t )1024 << header->ramsize; props->romsize_bytes = ( uint32_t )1024 << header->romsize; props->expramsize_bytes = ( uint32_t )1024 << header->expramsize; //dprintf("ramsize_bytes: %ld\n", props->ramsize_bytes); if ( props->ramsize_bytes > 32768 || props->ramsize_bytes < 2048 ) { props->ramsize_bytes = 0; } props->region = ( header->destcode <= 1 || header->destcode >= 13 ) ? 0 : 1; /*dprintf("ramsize_bytes: %ld\n", props->ramsize_bytes); */ } uint8_t smc_headerscore( uint32_t addr, snes_header_t *header ) { int score = 0; uint8_t reset_inst; uint16_t header_offset; if ( ( addr & 0xfff ) == 0x1b0 ) { header_offset = 0x200; } else { header_offset = 0; } if ( ( file_readblock( header, addr, sizeof( snes_header_t ) ) < sizeof( snes_header_t ) ) || file_res ) { return 0; } uint8_t mapper = header->map & ~0x10; uint16_t resetvector = header->vect_reset; /* not endian safe! */ uint32_t file_addr = ( ( ( addr - header_offset ) & ~0x7fff ) | ( resetvector & 0x7fff ) ) + header_offset; if ( resetvector < 0x8000 ) { return 0; } score += 2 * isFixed( &header->licensee, sizeof( header->licensee ), 0x33 ); score += 4 * checkChksum( header->cchk, header->chk ); if ( header->carttype < 0x08 ) { score++; } if ( header->romsize < 0x10 ) { score++; } if ( header->ramsize < 0x08 ) { score++; } if ( header->destcode < 0x0e ) { score++; } if ( ( addr - header_offset ) == 0x007fc0 && mapper == 0x20 ) { score += 2; } if ( ( addr - header_offset ) == 0x00ffc0 && mapper == 0x21 ) { score += 2; } if ( ( addr - header_offset ) == 0x007fc0 && mapper == 0x22 ) { score += 2; } if ( ( addr - header_offset ) == 0x40ffc0 && mapper == 0x25 ) { score += 2; } file_readblock( &reset_inst, file_addr, 1 ); switch ( reset_inst ) { case 0x78: /* sei */ case 0x18: /* clc */ case 0x38: /* sec */ case 0x9c: /* stz abs */ case 0x4c: /* jmp abs */ case 0x5c: /* jml abs */ score += 8; break; case 0xc2: /* rep */ case 0xe2: /* sep */ case 0xad: /* lda abs */ case 0xae: /* ldx abs */ case 0xac: /* ldy abs */ case 0xaf: /* lda abs long */ case 0xa9: /* lda imm */ case 0xa2: /* ldx imm */ case 0xa0: /* ldy imm */ case 0x20: /* jsr abs */ case 0x22: /* jsl abs */ score += 4; break; case 0x40: /* rti */ case 0x60: /* rts */ case 0x6b: /* rtl */ case 0xcd: /* cmp abs */ case 0xec: /* cpx abs */ case 0xcc: /* cpy abs */ score -= 4; break; case 0x00: /* brk */ case 0x02: /* cop */ case 0xdb: /* stp */ case 0x42: /* wdm */ case 0xff: /* sbc abs long indexed */ score -= 8; break; } if ( score && addr > 0x400000 ) { score += 4; } if ( score < 0 ) { score = 0; } return score; }