diff options
Diffstat (limited to 'src/mame/machine/seibuspi.c')
-rw-r--r-- | src/mame/machine/seibuspi.c | 388 |
1 files changed, 388 insertions, 0 deletions
diff --git a/src/mame/machine/seibuspi.c b/src/mame/machine/seibuspi.c new file mode 100644 index 00000000000..b9ad91b62ba --- /dev/null +++ b/src/mame/machine/seibuspi.c @@ -0,0 +1,388 @@ +#include "driver.h" + + + +/************************************************************************** + +Tile encryption +--------------- + +The tile graphics encryption uses the same algorithm in all games, with +different keys for the SPI, RISE10 and RISE11 custom chips. + +- Take 24 bits of gfx data (used to decrypt 4 pixels at 6 bpp) and perform + a bit permutation on them (the permutation is the same in all games). +- Take the low 12 bits of the tile code and add a 24-bit number (KEY1) to it. +- Add the two 24-bit numbers resulting from the above steps, but with a + catch: while performing the sum, some bits generate carry as usual, other + bits don't, depending on a 24-bit key (KEY2). Note that the carry generated + by bit 23 (if enabled) wraps around to bit 0. +- XOR the result with a 24-bit number (KEY3). + +The decryption is actually programmable; the games write the key to the +custom IC on startup!! (writes to 000414) + +**************************************************************************/ + +// add two numbers generating carry from one bit to the next only if +// the corresponding bit in carry_mask is 1 +static int partial_carry_sum(int add1,int add2,int carry_mask,int bits) +{ + int i,res,carry; + + res = 0; + carry = 0; + for (i = 0;i < bits;i++) + { + int bit = BIT(add1,i) + BIT(add2,i) + carry; + + res += (bit & 1) << i; + + // generate carry only if the corresponding bit in carry_mask is 1 + if (BIT(carry_mask,i)) + carry = bit >> 1; + else + carry = 0; + } + + // wrap around carry from top bit to bit 0 + if (carry) + res ^=1; + + return res; +} + +static int partial_carry_sum24(int add1,int add2,int carry_mask) +{ + return partial_carry_sum(add1,add2,carry_mask,24); +} + +static int partial_carry_sum16(int add1,int add2,int carry_mask) +{ + return partial_carry_sum(add1,add2,carry_mask,16); +} + +static int partial_carry_sum8(int add1,int add2,int carry_mask) +{ + return partial_carry_sum(add1,add2,carry_mask,8); +} + + + +static UINT32 decrypt_tile(UINT32 val, int tileno, UINT32 key1, UINT32 key2, UINT32 key3) +{ + val = BITSWAP24(val, 18,19,9,5, 10,17,16,20, 21,22,6,11, 15,14,4,23, 0,1,7,8, 13,12,3,2); + + return partial_carry_sum24( val, tileno + key1, key2 ) ^ key3; +} + +static void decrypt_text(UINT8 *rom, UINT32 key1, UINT32 key2, UINT32 key3) +{ + int i; + for(i=0; i<0x10000; i++) + { + UINT32 w; + + w = (rom[(i*3) + 0] << 16) | (rom[(i*3) + 1] << 8) | (rom[(i*3) +2]); + + w = decrypt_tile(w, i >> 4, key1, key2, key3); + + rom[(i*3) + 0] = (w >> 16) & 0xff; + rom[(i*3) + 1] = (w >> 8) & 0xff; + rom[(i*3) + 2] = w & 0xff; + } +} + +static void decrypt_bg(UINT8 *rom, int size, UINT32 key1, UINT32 key2, UINT32 key3) +{ + int i,j; + for(j=0; j<size; j+=0xc0000) + { + for(i=0; i<0x40000; i++) + { + UINT32 w; + + w = (rom[j + (i*3) + 0] << 16) | (rom[j + (i*3) + 1] << 8) | (rom[j + (i*3) + 2]); + + w = decrypt_tile(w, i >> 6, key1, key2, key3); + + rom[j + (i*3) + 0] = (w >> 16) & 0xff; + rom[j + (i*3) + 1] = (w >> 8) & 0xff; + rom[j + (i*3) + 2] = w & 0xff; + } + } +} + +/****************************************************************************************** +cpu #0 (PC=0033B2EB): unmapped program memory dword write to 00000414 = 00000000 & 0000FFFF +cpu #0 (PC=0033B2EB): unmapped program memory dword write to 00000414 = 0000DF5B & 0000FFFF +cpu #0 (PC=0033B2EB): unmapped program memory dword write to 00000414 = 000078CF & 0000FFFF +cpu #0 (PC=0033B2EB): unmapped program memory dword write to 00000414 = 00001377 & 0000FFFF +cpu #0 (PC=0033B2EB): unmapped program memory dword write to 00000414 = 00002538 & 0000FFFF +cpu #0 (PC=0033B2EB): unmapped program memory dword write to 00000414 = 00004535 & 0000FFFF +cpu #0 (PC=0033B2EB): unmapped program memory dword write to 00000414 = 06DC0000 & FFFF0000 +******************************************************************************************/ + +void seibuspi_text_decrypt(UINT8 *rom) +{ + decrypt_text( rom, 0x5a3845, 0x77cf5b, 0x1378df); +} + +void seibuspi_bg_decrypt(UINT8 *rom, int size) +{ + decrypt_bg( rom, size, 0x5a3845, 0x77cf5b, 0x1378df); +} + +/****************************************************************************************** +cpu #0 (PC=002A097D): unmapped program memory dword write to 00000414 = 00000001 & 0000FFFF +cpu #0 (PC=002A097D): unmapped program memory dword write to 00000414 = 0000DCF8 & 0000FFFF +cpu #0 (PC=002A097D): unmapped program memory dword write to 00000414 = 00007AE2 & 0000FFFF +cpu #0 (PC=002A097D): unmapped program memory dword write to 00000414 = 0000154D & 0000FFFF +cpu #0 (PC=002A097D): unmapped program memory dword write to 00000414 = 00001731 & 0000FFFF +cpu #0 (PC=002A097D): unmapped program memory dword write to 00000414 = 0000466B & 0000FFFF +cpu #0 (PC=002A097D): unmapped program memory dword write to 00000414 = 3EDC0000 & FFFF0000 +******************************************************************************************/ + +/* RISE10 (Raiden Fighters 2) */ +void seibuspi_rise10_text_decrypt(UINT8 *rom) +{ + decrypt_text( rom, 0x823146, 0x4de2f8, 0x157adc); +} + +void seibuspi_rise10_bg_decrypt(UINT8 *rom, int size) +{ + decrypt_bg( rom, size, 0x823146, 0x4de2f8, 0x157adc); +} + +/****************************************************************************************** +cpu #0 (PC=002C40F9): unmapped program memory dword write to 00000414 = 00000001 & 0000FFFF +cpu #0 (PC=002C40F9): unmapped program memory dword write to 00000414 = 00006630 & 0000FFFF +cpu #0 (PC=002C40F9): unmapped program memory dword write to 00000414 = 0000B685 & 0000FFFF +cpu #0 (PC=002C40F9): unmapped program memory dword write to 00000414 = 0000CCFE & 0000FFFF +cpu #0 (PC=002C40F9): unmapped program memory dword write to 00000414 = 000032A7 & 0000FFFF +cpu #0 (PC=002C40F9): unmapped program memory dword write to 00000414 = 0000547C & 0000FFFF +cpu #0 (PC=002C40F9): unmapped program memory dword write to 00000414 = 3EDC0000 & FFFF0000 +******************************************************************************************/ + +/* RISE11 (Raiden Fighters Jet) */ +void seibuspi_rise11_text_decrypt(UINT8 *rom) +{ + decrypt_text( rom, 0xaea754, 0xfe8530, 0xccb666); +} + +void seibuspi_rise11_bg_decrypt(UINT8 *rom, int size) +{ + decrypt_bg( rom, size, 0xaea754, 0xfe8530, 0xccb666); +} + + + + + + + + +static int dec12(int val) +{ + return partial_carry_sum16( val, 0x018a, 0x018a ) ^ 0xccd8; +} + +static int dec3(int val) +{ + return partial_carry_sum8( val, 0x05, 0x1d ) ^ 0x6c; +} + +static int dec4(int val) +{ + return partial_carry_sum8( val, 0x42, 0x46 ) ^ 0xa2; +} + +static int dec5(int val) +{ + return partial_carry_sum8( val, 0x21, 0x27 ) ^ 0x52; +} + +static int dec6(int val) +{ + return partial_carry_sum8( val, 0x08, 0x08 ) ^ 0x3a; +} + + +static void sprite_reorder(UINT8 *buffer) +{ + int j; + UINT8 temp[64]; + for( j=0; j < 16; j++ ) { + temp[2*(j*2)+0] = buffer[2*j+0]; + temp[2*(j*2)+1] = buffer[2*j+1]; + temp[2*(j*2)+2] = buffer[2*j+32]; + temp[2*(j*2)+3] = buffer[2*j+33]; + } + memcpy(buffer, temp, 64); +} + +/* actually this is for the 2000 version - original version might be different */ +void seibuspi_rise10_sprite_decrypt(UINT8 *rom, int size) +{ + int i,j; + int s = size/2; + + for( i=0; i < s; i+=32 ) { + sprite_reorder(&rom[2*i]); + sprite_reorder(&rom[2*(s+i)]); + sprite_reorder(&rom[2*((s*2)+i)]); + for( j=0; j < 32; j++ ) { + int b1,b2; + int d12,d3,d4,d5,d6; + + b1 = rom[2*((s*2)+i+j)] + (rom[2*((s*2)+i+j)+1] << 8) + (rom[2*(s+i+j)] << 16) + (rom[2*(s+i+j)+1] << 24); + b1 = BITSWAP32(b1, + 7,31,26,0,18,9,19,8, + 27,6,15,21,1,28,10,20, + 3,5,29,17,14,22,2,11, + 23,13,24,4,16,12,25,30); + b2 = rom[2*(i+j)] + (rom[2*(i+j)+1] << 8); + + d12 = dec12(b2); + d3 = dec3((b1 >> 0) & 0xff); + d4 = dec4((b1 >> 8) & 0xff); + d5 = dec5((b1 >> 16) & 0xff); + d6 = dec6((b1 >> 24) & 0xff); + + rom[2*(i+j)] = d12 >> 8; + rom[2*(i+j)+1] = d12; + rom[2*(s+i+j)] = d3; + rom[2*(s+i+j)+1] = d4; + rom[2*((s*2)+i+j)] = d5; + rom[2*((s*2)+i+j)+1] = d6; + } + } +} + + + + +/****************************************************************************************** + +rf2_eur (we don't have the gfx ROMs for this one) + +cpu #0 (PC=002A097D): unmapped program memory dword write to 0000054C = 00000000 & 0000FFFF +cpu #0 (PC=002A097D): unmapped program memory dword write to 0000054C = 0000ABCB & 0000FFFF +cpu #0 (PC=002A097D): unmapped program memory dword write to 0000054C = 0000ABCB & 0000FFFF +cpu #0 (PC=002A097D): unmapped program memory dword write to 0000054C = 00006543 & 0000FFFF +cpu #0 (PC=002A097D): unmapped program memory dword write to 0000054C = 000021D9 & 0000FFFF +cpu #0 (PC=002A097D): unmapped program memory dword write to 0000054C = 00006655 & 0000FFFF +cpu #0 (PC=002A097D): unmapped program memory dword write to 0000054C = 000099AA & 0000FFFF +cpu #0 (PC=002A097D): unmapped program memory dword write to 0000054C = 00006655 & 0000FFFF +cpu #0 (PC=002A097D): unmapped program memory dword write to 0000054C = 000099AA & 0000FFFF +cpu #0 (PC=002A097D): unmapped program memory dword write to 0000054C = 00000C1D & 0000FFFF +cpu #0 (PC=002A097D): unmapped program memory dword write to 0000054C = 0000A346 & 0000FFFF +cpu #0 (PC=002A097D): unmapped program memory dword write to 0000054C = 00005237 & 0000FFFF +cpu #0 (PC=002A097D): unmapped program memory dword write to 0000054C = 0000A948 & 0000FFFF + + plane543 = partial_carry_sum24( plane543, 0x??????, 0x??2199 ) ^ 0x??d9aa; + plane210 = partial_carry_sum24( plane210, i, 0x990c52 ) ^ 0xaa1d37; + +rfjet + +cpu #0 (PC=002C40F9): unmapped program memory dword write to 0000054C = 00000000 & 0000FFFF +cpu #0 (PC=002C40F9): unmapped program memory dword write to 0000054C = 00000000 & 0000FFFF +cpu #0 (PC=002C40F9): unmapped program memory dword write to 0000054C = 000055AB & 0000FFFF +cpu #0 (PC=002C40F9): unmapped program memory dword write to 0000054C = 00000000 & 0000FFFF +cpu #0 (PC=002C40F9): unmapped program memory dword write to 0000054C = 0000AA6A & 0000FFFF // +cpu #0 (PC=002C40F9): unmapped program memory dword write to 0000054C = 0000ABCB & 0000FFFF +cpu #0 (PC=002C40F9): unmapped program memory dword write to 0000054C = 0000DD4C & 0000FFFF // +cpu #0 (PC=002C40F9): unmapped program memory dword write to 0000054C = 00006543 & 0000FFFF +cpu #0 (PC=002C40F9): unmapped program memory dword write to 0000054C = 0000D68B & 0000FFFF // +cpu #0 (PC=002C40F9): unmapped program memory dword write to 0000054C = 000037F2 & 0000FFFF // +cpu #0 (PC=002C40F9): unmapped program memory dword write to 0000054C = 000021D9 & 0000FFFF +cpu #0 (PC=002C40F9): unmapped program memory dword write to 0000054C = 00005B3B & 0000FFFF // +cpu #0 (PC=002C40F9): unmapped program memory dword write to 0000054C = 00000300 & 0000FFFF + + plane543 = partial_carry_sum24( plane543, 0x01cb64, 0x01aadd ) ^ 0x016a4c; + plane210 = partial_carry_sum24( plane210, i, 0xd6375b ) ^ 0x8bf23b; + +******************************************************************************************/ + + +void seibuspi_rise11_sprite_decrypt(UINT8 *rom, int size) +{ + int i; + + for (i = 0; i < size/2; i++) + { + int b1,b2,b3; + int plane543,plane210; + + b1 = rom[0*size+2*i] + (rom[0*size+2*i+1] << 8); + b2 = rom[1*size+2*i] + (rom[1*size+2*i+1] << 8); + b3 = rom[2*size+2*i] + (rom[2*size+2*i+1] << 8); + + plane543 = (BIT(b2,11)<< 0) | + (BIT(b1, 6)<< 1) | + (BIT(b3,12)<< 2) | + (BIT(b3, 3)<< 3) | + (BIT(b2,12)<< 4) | + (BIT(b3,14)<< 5) | + (BIT(b3, 4)<< 6) | + (BIT(b1,11)<< 7) | + (BIT(b1,12)<< 8) | + (BIT(b1, 2)<< 9) | + (BIT(b2, 5)<<10) | + (BIT(b1, 9)<<11) | + (BIT(b3, 1)<<12) | + (BIT(b2, 2)<<13) | + (BIT(b2,10)<<14) | + (BIT(b3, 5)<<15) | + (BIT(b1, 3)<<16) | + (BIT(b2, 7)<<17) | + (BIT(b1,15)<<18) | + (BIT(b3, 9)<<19) | + (BIT(b2,13)<<20) | + (BIT(b1, 4)<<21) | + (BIT(b3, 2)<<22) | + (BIT(b2, 0)<<23); + + plane210 = (BIT(b1,14)<< 0) | + (BIT(b1, 1)<< 1) | + (BIT(b1,13)<< 2) | + (BIT(b3, 0)<< 3) | + (BIT(b1, 7)<< 4) | + (BIT(b2,14)<< 5) | + (BIT(b2, 4)<< 6) | + (BIT(b2, 9)<< 7) | + (BIT(b3, 8)<< 8) | + (BIT(b2, 1)<< 9) | + (BIT(b3, 7)<<10) | + (BIT(b2, 6)<<11) | + (BIT(b1, 0)<<12) | + (BIT(b3,11)<<13) | + (BIT(b2, 8)<<14) | + (BIT(b3,13)<<15) | + (BIT(b1, 8)<<16) | + (BIT(b3,10)<<17) | + (BIT(b3, 6)<<18) | + (BIT(b1,10)<<19) | + (BIT(b2,15)<<20) | + (BIT(b2, 3)<<21) | + (BIT(b1, 5)<<22) | + (BIT(b3,15)<<23); + + plane543 = partial_carry_sum24( plane543, 0x01cb64, 0x01aadd ) ^ 0x016a4c; + plane210 = partial_carry_sum24( plane210, i, 0xd6375b ) ^ 0x8bf23b; + + rom[0*size+2*i] = plane543 >> 16; + rom[0*size+2*i+1] = plane543 >> 8; + rom[1*size+2*i] = plane543 >> 0; + rom[1*size+2*i+1] = plane210 >> 16; + rom[2*size+2*i] = plane210 >> 8; + rom[2*size+2*i+1] = plane210 >> 0; + } + + for (i = 0; i < size/2; i += 32) + { + sprite_reorder(&rom[0*size+2*i]); + sprite_reorder(&rom[1*size+2*i]); + sprite_reorder(&rom[2*size+2*i]); + } +} |