/* ======================================================================== */ /* INTELLICART ROM manipulation routines. J. Zbiciak, 2001 */ /* */ /* These routines are intended for reading and writing Intellicart ROM */ /* images. Portions of this code are based on Chad Schell's own routines */ /* for generating Intellicart ROM images. */ /* ======================================================================== */ /* ======================================================================== */ /* 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; either version 2 of the License, or */ /* (at your option) any later version. */ /* */ /* 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., 675 Mass Ave, Cambridge, MA 02139, USA. */ /* ======================================================================== */ /* Copyright (c) 2001-+Inf, Joseph Zbiciak */ /* ======================================================================== */ #include #include #include "config.h" #include "icartrom.h" #include "crc16.h" #define SET_BIT(bv,idx) do { \ int _ = (idx); \ (bv)[_ >> 5] |= 1 << (_ & 31); \ } while(0) #define CLR_BIT(bv,idx) do { \ int _ = (idx); \ (bv)[_ >> 5] &= ~(1 << (_ & 31)); \ } while(0) #define GET_BIT(bv,i,b) do { \ int _ = (i); \ b = ((bv)[_ >> 5] >> (_ & 31)) & 1; \ } while(0) /* ======================================================================== */ /* ICARTROM_INIT -- Initialize an Intellicart image to defaults. */ /* ======================================================================== */ void icartrom_init(icartrom_t *rom) { if (rom) memset(rom, 0, sizeof(icartrom_t)); } /* ======================================================================== */ /* ICARTROM_ADDSEG -- Adds a segment to an Intellcart ROM structure. */ /* ======================================================================== */ int icartrom_addseg ( icartrom_t *rom, /* Intellicart ROM structure. */ uint_16 *data, /* Data to insert into the ROM. May be NULL. */ uint_32 addr, /* Address to insert the data at. */ uint_32 len, /* Length of the data to insert. */ uint_8 set_attr, /* Attributes to set (read, write, banksw). */ uint_8 clr_attr /* Attributes to clear */ ) { uint_32 p, a; /* jzp_printf("ADDSEG: addr %.4X len %.4X set %.2X clr %.2X\n", addr, len, set_attr, clr_attr);*/ /* -------------------------------------------------------------------- */ /* Sanity checks: */ /* -------------------------------------------------------------------- */ if (!rom) return -1; /* Valid ROM pointer? */ if (addr + len > 0x10000) return -1; /* addr + len doesn't wrap? */ /* -------------------------------------------------------------------- */ /* Next, if any actual data was provided, memcpy() it into the ICart */ /* -------------------------------------------------------------------- */ if (data) { set_attr |= ICARTROM_PRELOAD; /* Force these pages to be preloaded */ clr_attr &= ~ICARTROM_PRELOAD; /* Force these pages to be preloaded */ memcpy(rom->image + addr, data, len * sizeof(uint_16)); } /* -------------------------------------------------------------------- */ /* Now, on the range specified, update the various attributes. */ /* -------------------------------------------------------------------- */ for (a = addr; a < addr + len; a += 256) { p = a >> 8; if (set_attr & ICARTROM_PRELOAD) SET_BIT(rom->preload , p); if (set_attr & ICARTROM_READ ) SET_BIT(rom->readable, p); if (set_attr & ICARTROM_WRITE ) SET_BIT(rom->writable, p); if (set_attr & ICARTROM_NARROW ) SET_BIT(rom->narrow , p); if (set_attr & ICARTROM_BANKSW ) SET_BIT(rom->dobanksw, p); if (clr_attr & ICARTROM_PRELOAD) CLR_BIT(rom->preload , p); if (clr_attr & ICARTROM_READ ) CLR_BIT(rom->readable, p); if (clr_attr & ICARTROM_WRITE ) CLR_BIT(rom->writable, p); if (clr_attr & ICARTROM_NARROW ) CLR_BIT(rom->narrow , p); if (clr_attr & ICARTROM_BANKSW ) CLR_BIT(rom->dobanksw, p); /* jzp_printf("ATTR: set %.2X clr %.2X on %.2X00\n", set_attr,clr_attr,p);*/ if (a + 255 > addr + len) p = (addr + len - 1) >> 8; else p = (a + 255 - 1) >> 8; if (set_attr & ICARTROM_PRELOAD) SET_BIT(rom->preload , p); if (set_attr & ICARTROM_READ ) SET_BIT(rom->readable, p); if (set_attr & ICARTROM_WRITE ) SET_BIT(rom->writable, p); if (set_attr & ICARTROM_NARROW ) SET_BIT(rom->narrow , p); if (set_attr & ICARTROM_BANKSW ) SET_BIT(rom->dobanksw, p); if (clr_attr & ICARTROM_PRELOAD) CLR_BIT(rom->preload , p); if (clr_attr & ICARTROM_READ ) CLR_BIT(rom->readable, p); if (clr_attr & ICARTROM_WRITE ) CLR_BIT(rom->writable, p); if (clr_attr & ICARTROM_NARROW ) CLR_BIT(rom->narrow , p); if (clr_attr & ICARTROM_BANKSW ) CLR_BIT(rom->dobanksw, p); /* jzp_printf("ATTR: set %.2X clr %.2X on %.2X00\n", set_attr,clr_attr,p);*/ } return 0; /*SUCCESS*/ } /* ======================================================================== */ /* ICARTROM_GENROM -- Generate a .ROM image from an icartrom_t. */ /* ======================================================================== */ uint_8 *icartrom_genrom(icartrom_t *rom, uint_32 *rom_size, ictype_t type) { uint_32 size; uint_8 bank_attr[32]; uint_8 fine_addr[32]; uint_8 seg_lo[128], seg_hi[128]; int num_seg; int i, j, lo, hi, b, tmp, attr, ofs; uint_8 *rom_img; uint_16 crc; /* -------------------------------------------------------------------- */ /* Sanity checks. */ /* -------------------------------------------------------------------- */ if (!rom || !rom_size) return NULL; *rom_size = 0; /* -------------------------------------------------------------------- */ /* Scan the memory map looking for segments of memory image to dl. */ /* -------------------------------------------------------------------- */ for (i = num_seg = 0, lo = hi = -1; i <= 256; i++) { if (i != 256) { GET_BIT(rom->preload, i, b); } else { b = 0; } if (b) { hi = i; /* extend upper end of segment */ if (lo == -1) { lo = i; } /* detect start of a segment */ } else { if (lo >= 0) { seg_lo[num_seg] = lo; seg_hi[num_seg] = hi; num_seg++; } hi = lo = -1; } } /* -------------------------------------------------------------------- */ /* Now, build up the attribute flags and fine-address ranges. */ /* -------------------------------------------------------------------- */ for (i = 0; i < 256; i += 8) { uint_8 page[8]; /* attrs for pages within 2K bank */ /* ---------------------------------------------------------------- */ /* First, generate the union of all attributes in this 2K bank. */ /* ---------------------------------------------------------------- */ for (j = attr = 0; j < 8; j++) { tmp = 0; GET_BIT(rom->readable, (i+j), b); if (b) tmp |= ICARTROM_READ; GET_BIT(rom->writable, (i+j), b); if (b) tmp |= ICARTROM_WRITE; GET_BIT(rom->narrow, (i+j), b); if (b) tmp |= ICARTROM_NARROW; GET_BIT(rom->dobanksw, (i+j), b); if (b) tmp |= ICARTROM_BANKSW; attr |= tmp; page[j] = tmp; } /* ---------------------------------------------------------------- */ /* No attributes? Go to next 2K bank. */ /* ---------------------------------------------------------------- */ if (!attr) { fine_addr[i >> 3] = 0x07; bank_attr[i >> 3] = 0x00; continue; } /* ---------------------------------------------------------------- */ /* Next, determine the range of addresses that have any bits set. */ /* Warn if some pages don't have all of the attributes that the */ /* bank will end up having. */ /* ---------------------------------------------------------------- */ for (j = 0, lo = hi = -1; j < 8; j++) { if (page[j]) { if (lo == -1) lo = j; hi = j; if ((page[j] & attr) != attr) { /* put warning here */ } } } /* ---------------------------------------------------------------- */ /* Store out the final fine-address range and bank attributes. */ /* ---------------------------------------------------------------- */ assert (lo != -1 && hi != -1); fine_addr[i >> 3] = (lo << 4) | hi; bank_attr[i >> 3] = attr; } /* -------------------------------------------------------------------- */ /* Next, calculate the size of the .ROM image. The .ROM format has */ /* the following fixed and variable costs: */ /* */ /* -- Header: 3 bytes (fixed) */ /* -- Attribute Table: 16 bytes (fixed) */ /* -- Fine Addr Table: 32 bytes (fixed) */ /* -- Table Checksum: 2 bytes (fixed) */ /* ------------------ */ /* 53 bytes total fixed overhead */ /* */ /* -- ROM segments: 4 + 2*num_words per segment. */ /* -------------------------------------------------------------------- */ size = 53; for (i = 0; i < num_seg; i++) size += 512 * (seg_hi[i] - seg_lo[i] + 1) + 4; *rom_size = size; /* Report the size to the caller. */ /* -------------------------------------------------------------------- */ /* Allocate a hunk of memory for the .ROM file. */ /* -------------------------------------------------------------------- */ if ((rom_img = calloc(size, 1)) == NULL) return NULL; /* fail if out-of-memory. */ /* -------------------------------------------------------------------- */ /* Now, construct the .ROM image. */ /* First: The header. */ /* -------------------------------------------------------------------- */ switch (type) { case ICART: rom_img[0] = 0xA8; /* Autobaud Rate-Detection Byte */ break; case CC3_STD: rom_img[0] = 0x41; /* Autobaud Rate-Detection Byte */ break; case CC3_ADV: rom_img[0] = 0x61; /* Autobaud Rate-Detection Byte */ break; default: free(rom_img); /* Fail on unknown type. */ return NULL; } rom_img[1] = num_seg; /* Number of ROM segments in image. */ rom_img[2] = num_seg ^ 0xFF; /* 1s Complement of # of segments. */ /* -------------------------------------------------------------------- */ /* Next: The ROM segments. */ /* -------------------------------------------------------------------- */ for (i = 0, ofs = 3; i < num_seg; i++) { int start_ofs, len; start_ofs = ofs; /* ---------------------------------------------------------------- */ /* Inclusive segment range. (upper 8 of addresses) */ /* ---------------------------------------------------------------- */ rom_img[ofs++] = seg_lo[i]; rom_img[ofs++] = seg_hi[i]; lo = seg_lo[i] << 8; hi = (seg_hi[i] << 8) + 0x100; len = 2*(hi - lo) + 2; /* +2 to include header */ /* ---------------------------------------------------------------- */ /* Actual ROM image data in big-endian format. */ /* ---------------------------------------------------------------- */ for (j = lo; j < hi; j++) { rom_img[ofs++] = rom->image[j] >> 8; rom_img[ofs++] = rom->image[j] & 0xFF; } /* ---------------------------------------------------------------- */ /* ROM segment checksum (CRC-16), also big-endian. */ /* ---------------------------------------------------------------- */ crc = crc16_block(0xFFFF, rom_img + start_ofs, len); rom_img[ofs++] = crc >> 8; rom_img[ofs++] = crc & 0xFF; } /* -------------------------------------------------------------------- */ /* Last: The attribute and fine-address tables. */ /* -------------------------------------------------------------------- */ for (i = 0; i < 16; i++) rom_img[ofs++] = bank_attr[i*2 + 0] | (bank_attr[i*2 + 1] << 4); for (j = 0; j < 2; j++) for (i = 0; i < 16; i++) rom_img[ofs++] = fine_addr[i*2 + j]; crc = crc16_block(0xFFFF, rom_img + ofs - 48, 48); rom_img[ofs++] = crc >> 8; rom_img[ofs++] = crc & 0xFF; /* -------------------------------------------------------------------- */ /* Return the completed .ROM image. */ /* -------------------------------------------------------------------- */ return rom_img; } /* ======================================================================== */ /* ICARTROM_DECODE -- Decode a .ROM image into an icartrom_t. */ /* ======================================================================== */ int icartrom_decode ( icartrom_t *rom, uint_8 *rom_img, int ignore_crc ) { int num_seg, lo, hi, i, j, ofs, p, attr; uint_16 crc_expect, crc_actual; /* -------------------------------------------------------------------- */ /* Sanity checks. */ /* -------------------------------------------------------------------- */ if (!rom_img) return -1; /* -------------------------------------------------------------------- */ /* First, check to see if the header passes initial muster. */ /* -------------------------------------------------------------------- */ if ((rom_img[0] != 0xA8 && (rom_img[0] & ~0x20) != 0x41) || rom_img[1] != (0xFF ^ rom_img[2])) return -2; /* Bad header */ /* -------------------------------------------------------------------- */ /* Step through the ROM segments. */ /* -------------------------------------------------------------------- */ num_seg = rom_img[1]; ofs = 3; for (i = 0; i < num_seg; i++) { int start; /* ---------------------------------------------------------------- */ /* Get the range of addresses for the ROM segment. */ /* ---------------------------------------------------------------- */ start = ofs; lo = rom_img[ofs++] << 8; hi = (rom_img[ofs++] << 8) + 0x100; if (hi < lo) return -4; /* Bad ROM segment address range. */ if (!rom) ofs += 2 * (hi - lo); else for (j = lo; j < hi; j++) { rom->image[j] = (rom_img[ofs] << 8) | (rom_img[ofs + 1] & 0xFF); ofs += 2; } /* ---------------------------------------------------------------- */ /* Mark the "preload" bits for this ROM segment. */ /* ---------------------------------------------------------------- */ if (rom) for (j = lo >> 8; j < (hi >> 8); j++) SET_BIT(rom->preload, j); /* ---------------------------------------------------------------- */ /* Check the CRC-16, unless instructed not to. (We might do this */ /* to try to rescue a corrupt or tweaked ROM or something.) */ /* ---------------------------------------------------------------- */ if (!ignore_crc) { crc_expect = (rom_img[ofs] << 8) | (rom_img[ofs + 1] & 0xFF); crc_actual = crc16_block(0xFFFF, rom_img + start, 2 * (hi-lo) + 2); if (crc_expect != crc_actual) return -3; /* CRC error in ROM segments. */ } ofs += 2; /* step over CRC */ } /* -------------------------------------------------------------------- */ /* Unpack the attributes into our bitmaps. */ /* -------------------------------------------------------------------- */ for (i = 0; i < 32; i++) { /* ---------------------------------------------------------------- */ /* Get our attribute and fine-address bits from the right nibbles. */ /* ---------------------------------------------------------------- */ attr = 0xF & (rom_img[ofs + (i >> 1)] >> ((i & 1) * 4)); hi = rom_img[ofs + 16 + ((i >> 1) | ((i & 1) << 4))]; lo = (hi >> 4) & 0x7; hi = (hi & 0x7) + 1; /* ---------------------------------------------------------------- */ /* Sanity checks. */ /* ---------------------------------------------------------------- */ if (hi < lo) return -5; /* Bad fine-address range */ if (!attr || !rom) continue; /* ---------------------------------------------------------------- */ /* Apply attributes to our fine-address range. */ /* ---------------------------------------------------------------- */ for (j = lo; j < hi; j++) { p = (i << 3) + j; if (attr & ICARTROM_READ ) SET_BIT(rom->readable, p); if (attr & ICARTROM_WRITE ) SET_BIT(rom->writable, p); if (attr & ICARTROM_NARROW) SET_BIT(rom->narrow , p); if (attr & ICARTROM_BANKSW) SET_BIT(rom->dobanksw, p); } } /* -------------------------------------------------------------------- */ /* Check the CRC on our attributes. */ /* -------------------------------------------------------------------- */ if (!ignore_crc) { crc_expect = (rom_img[ofs + 48] << 8) | (rom_img[ofs + 49] & 0xFF); crc_actual = crc16_block(0xFFFF, rom_img + ofs, 48); if (crc_expect != crc_actual) return -6; /* CRC error in enable tables */ } ofs += 50; /* -------------------------------------------------------------------- */ /* Return the total number of bytes decoded. */ /* -------------------------------------------------------------------- */ return ofs; } /* ======================================================================== */ /* ICARTROM_READFILE -- Reads a file into an icartrom_t. */ /* ======================================================================== */ int icartrom_readfile(char *fname, icartrom_t *the_icart) { int len, decoded; uint_8 *rom_img; FILE *f; f = fopen(fname, "rb"); if (!f) { perror("fopen()"); fprintf(stderr, "ERROR: Couldn't open '%s' for reading\n", fname); exit(1); } fseek(f, 0, SEEK_END); if ((len = ftell(f)) < 0) { perror("fseek()"); fprintf(stderr, "ERROR: Error seeking while reading '%s'\n", fname); exit(1); } rewind(f); if ((rom_img = malloc(len)) == NULL) { perror("malloc()"); fprintf(stderr, "ERROR: Out of memory decoding '%s'\n", fname); exit(1); } fread(rom_img, 1, len, f); fclose(f); decoded = icartrom_decode(the_icart, rom_img, 0); free(rom_img); return decoded; } /* ======================================================================== */ /* ICARTROM_WRITEFILE -- Writes a file from an icartrom_t. */ /* ======================================================================== */ uint_32 icartrom_writefile(char *fname, icartrom_t *the_icart, ictype_t type) { uint_32 size = 0; uint_8 *rom_img = NULL; FILE *fr; fr = fopen(fname, "wb"); if (!fr) { fprintf(stderr, "ERROR: Could not open '%s' for writing\n", fname); exit(1); } rom_img = icartrom_genrom(the_icart, &size, type); if (!rom_img) { fprintf(stderr, "ERROR: No ROM image generated?\n"); exit(1); } fwrite(rom_img, 1, size, fr); fclose(fr); return size; } /* ======================================================================== */ /* Copyright (c) 2001-+Inf, Joseph Zbiciak */ /* ======================================================================== */