/* * x76f100.c * * Secure SerialFlash * * The X76F100 is a Password Access Security Supervisor, containing one 896-bit Secure SerialFlash array. * Access to the memory array can be controlled by two 64-bit passwords. These passwords protect read and * write operations of the memory array. * */ #include "emu.h" #include "machine/x76f100.h" #define VERBOSE_LEVEL ( 0 ) INLINE void ATTR_PRINTF(3,4) verboselog( running_machine *machine, int n_level, const char *s_fmt, ... ) { if( VERBOSE_LEVEL >= n_level ) { va_list v; char buf[ 32768 ]; va_start( v, s_fmt ); vsprintf( buf, s_fmt, v ); va_end( v ); logerror( "%s: %s", cpuexec_describe_context(machine), buf ); } } #define SIZE_WRITE_BUFFER ( 8 ) struct x76f100_chip { int cs; int rst; int scl; int sdaw; int sdar; int state; int shift; int bit; int byte; int command; UINT8 write_buffer[ SIZE_WRITE_BUFFER ]; UINT8 *response_to_reset; UINT8 *write_password; UINT8 *read_password; UINT8 *data; }; #define SIZE_RESPONSE_TO_RESET ( 4 ) #define SIZE_WRITE_PASSWORD ( SIZE_WRITE_BUFFER ) #define SIZE_READ_PASSWORD ( SIZE_WRITE_BUFFER ) #define SIZE_DATA ( 112 ) static struct x76f100_chip x76f100[ X76F100_MAXCHIP ]; #define COMMAND_WRITE ( 0x80 ) #define COMMAND_READ ( 0x81 ) #define COMMAND_CHANGE_WRITE_PASSWORD ( 0xfc ) #define COMMAND_CHANGE_READ_PASSWORD ( 0xfe ) #define COMMAND_ACK_PASSWORD ( 0x55 ) #define STATE_STOP ( 0 ) #define STATE_RESPONSE_TO_RESET ( 1 ) #define STATE_LOAD_COMMAND ( 2 ) #define STATE_LOAD_PASSWORD ( 4 ) #define STATE_VERIFY_PASSWORD ( 5 ) #define STATE_READ_DATA ( 6 ) #define STATE_WRITE_DATA ( 7 ) void x76f100_init( running_machine *machine, int chip, UINT8 *data ) { int offset; struct x76f100_chip *c; if( chip >= X76F100_MAXCHIP ) { verboselog( machine, 0, "x76f100_init( %d ) chip out of range\n", chip ); return; } c = &x76f100[ chip ]; if( data == NULL ) { data = auto_alloc_array( machine, UINT8, SIZE_RESPONSE_TO_RESET + SIZE_READ_PASSWORD + SIZE_WRITE_PASSWORD + SIZE_DATA ); } c->cs = 0; c->rst = 0; c->scl = 0; c->sdaw = 0; c->sdar = 0; c->state = STATE_STOP; c->shift = 0; c->bit = 0; c->byte = 0; c->command = 0; memset( c->write_buffer, 0, SIZE_WRITE_BUFFER ); offset = 0; c->response_to_reset = &data[ offset ]; offset += SIZE_RESPONSE_TO_RESET; c->write_password = &data[ offset ]; offset += SIZE_WRITE_PASSWORD; c->read_password = &data[ offset ]; offset += SIZE_READ_PASSWORD; c->data = &data[ offset ]; offset += SIZE_DATA; state_save_register_item( machine, "x76f100", NULL, chip, c->cs ); state_save_register_item( machine, "x76f100", NULL, chip, c->rst ); state_save_register_item( machine, "x76f100", NULL, chip, c->scl ); state_save_register_item( machine, "x76f100", NULL, chip, c->sdaw ); state_save_register_item( machine, "x76f100", NULL, chip, c->sdar ); state_save_register_item( machine, "x76f100", NULL, chip, c->state ); state_save_register_item( machine, "x76f100", NULL, chip, c->shift ); state_save_register_item( machine, "x76f100", NULL, chip, c->bit ); state_save_register_item( machine, "x76f100", NULL, chip, c->byte ); state_save_register_item( machine, "x76f100", NULL, chip, c->command ); state_save_register_item_array( machine, "x76f100", NULL, chip, c->write_buffer ); state_save_register_item_pointer( machine, "x76f100", NULL, chip, c->response_to_reset, SIZE_RESPONSE_TO_RESET ); state_save_register_item_pointer( machine, "x76f100", NULL, chip, c->write_password, SIZE_WRITE_PASSWORD ); state_save_register_item_pointer( machine, "x76f100", NULL, chip, c->read_password, SIZE_READ_PASSWORD ); state_save_register_item_pointer( machine, "x76f100", NULL, chip, c->data, SIZE_DATA ); } void x76f100_cs_write( running_machine *machine, int chip, int cs ) { struct x76f100_chip *c; if( chip >= X76F100_MAXCHIP ) { verboselog( machine, 0, "x76f100_cs_write( %d ) chip out of range\n", chip ); return; } c = &x76f100[ chip ]; if( c->cs != cs ) { verboselog( machine, 2, "x76f100(%d) cs=%d\n", chip, cs ); } if( c->cs != 0 && cs == 0 ) { /* enable chip */ c->state = STATE_STOP; } if( c->cs == 0 && cs != 0 ) { /* disable chip */ c->state = STATE_STOP; /* high impendence? */ c->sdar = 0; } c->cs = cs; } void x76f100_rst_write( running_machine *machine, int chip, int rst ) { struct x76f100_chip *c; if( chip >= X76F100_MAXCHIP ) { verboselog( machine, 0, "x76f100_rst_write( %d ) chip out of range\n", chip ); return; } c = &x76f100[ chip ]; if( c->rst != rst ) { verboselog( machine, 2, "x76f100(%d) rst=%d\n", chip, rst ); } if( c->rst == 0 && rst != 0 && c->cs == 0 ) { verboselog( machine, 1, "x76f100(%d) goto response to reset\n", chip ); c->state = STATE_RESPONSE_TO_RESET; c->bit = 0; c->byte = 0; } c->rst = rst; } static UINT8 *x76f100_password( struct x76f100_chip *c ) { if( ( c->command & 0xe1 ) == COMMAND_READ ) { return c->read_password; } return c->write_password; } static void x76f100_password_ok( struct x76f100_chip *c ) { if( ( c->command & 0xe1 ) == COMMAND_READ ) { c->state = STATE_READ_DATA; } else if( ( c->command & 0xe1 ) == COMMAND_WRITE ) { c->state = STATE_WRITE_DATA; } else { /* TODO: */ } } static int x76f100_data_offset( struct x76f100_chip *c ) { int block_offset = ( c->command >> 1 ) & 0x0f; return ( block_offset * SIZE_WRITE_BUFFER ) + c->byte; } void x76f100_scl_write( running_machine *machine, int chip, int scl ) { struct x76f100_chip *c; if( chip >= X76F100_MAXCHIP ) { verboselog( machine, 0, "x76f100_scl_write( %d ) chip out of range\n", chip ); return; } c = &x76f100[ chip ]; if( c->scl != scl ) { verboselog( machine, 2, "x76f100(%d) scl=%d\n", chip, scl ); } if( c->cs == 0 ) { switch( c->state ) { case STATE_STOP: break; case STATE_RESPONSE_TO_RESET: if( c->scl != 0 && scl == 0 ) { if( c->bit == 0 ) { c->shift = c->response_to_reset[ c->byte ]; verboselog( machine, 1, "x76f100(%d) <- response_to_reset[%d]: %02x\n", chip, c->byte, c->shift ); } c->sdar = c->shift & 1; c->shift >>= 1; c->bit++; if( c->bit == 8 ) { c->bit = 0; c->byte++; if( c->byte == 4 ) { c->byte = 0; } } } break; case STATE_LOAD_COMMAND: case STATE_LOAD_PASSWORD: case STATE_VERIFY_PASSWORD: case STATE_WRITE_DATA: if( c->scl == 0 && scl != 0 ) { if( c->bit < 8 ) { verboselog( machine, 2, "x76f100(%d) clock\n", chip ); c->shift <<= 1; if( c->sdaw != 0 ) { c->shift |= 1; } c->bit++; } else { c->sdar = 0; switch( c->state ) { case STATE_LOAD_COMMAND: c->command = c->shift; verboselog( machine, 1, "x76f100(%d) -> command: %02x\n", chip, c->command ); /* todo: verify command is valid? */ c->state = STATE_LOAD_PASSWORD; break; case STATE_LOAD_PASSWORD: verboselog( machine, 1, "x76f100(%d) -> password: %02x\n", chip, c->shift ); c->write_buffer[ c->byte++ ] = c->shift; if( c->byte == SIZE_WRITE_BUFFER ) { c->state = STATE_VERIFY_PASSWORD; } break; case STATE_VERIFY_PASSWORD: verboselog( machine, 1, "x76f100(%d) -> verify password: %02x\n", chip, c->shift ); /* todo: this should probably be handled as a command */ if( c->shift == COMMAND_ACK_PASSWORD ) { /* todo: this should take 10ms before it returns ok. */ if( memcmp( x76f100_password( c ), c->write_buffer, SIZE_WRITE_BUFFER ) == 0 ) { x76f100_password_ok( c ); } else { c->sdar = 1; } } break; case STATE_WRITE_DATA: verboselog( machine, 1, "x76f100(%d) -> data: %02x\n", chip, c->shift ); c->write_buffer[ c->byte++ ] = c->shift; if( c->byte == SIZE_WRITE_BUFFER ) { for( c->byte = 0; c->byte < SIZE_WRITE_BUFFER; c->byte++ ) { c->data[ x76f100_data_offset( c ) ] = c->write_buffer[ c->byte ]; } c->byte = 0; verboselog( machine, 1, "x76f100(%d) data flushed\n", chip ); } break; } c->bit = 0; c->shift = 0; } } break; case STATE_READ_DATA: if( c->scl == 0 && scl != 0 ) { if( c->bit < 8 ) { if( c->bit == 0 ) { switch( c->state ) { case STATE_READ_DATA: c->shift = c->data[ x76f100_data_offset( c ) ]; verboselog( machine, 1, "x76f100(%d) <- data: %02x\n", chip, c->shift ); break; } } c->sdar = ( c->shift >> 7 ) & 1; c->shift <<= 1; c->bit++; } else { c->bit = 0; c->sdar = 0; if( c->sdaw == 0 ) { verboselog( machine, 2, "x76f100(%d) ack <-\n", chip ); c->byte++; } else { verboselog( machine, 2, "x76f100(%d) nak <-\n", chip ); } } } break; } } c->scl = scl; } void x76f100_sda_write( running_machine *machine, int chip, int sda ) { struct x76f100_chip *c; if( chip >= X76F100_MAXCHIP ) { verboselog( machine, 0, "x76f100_sda_write( %d ) chip out of range\n", chip ); return; } c = &x76f100[ chip ]; if( c->sdaw != sda ) { verboselog( machine, 2, "x76f100(%d) sdaw=%d\n", chip, sda ); } if( c->cs == 0 && c->scl != 0 ) { if( c->sdaw == 0 && sda != 0 ) { verboselog( machine, 1, "x76f100(%d) goto stop\n", chip ); c->state = STATE_STOP; c->sdar = 0; } if( c->sdaw != 0 && sda == 0 ) { switch( c->state ) { case STATE_STOP: verboselog( machine, 1, "x76f100(%d) goto start\n", chip ); c->state = STATE_LOAD_COMMAND; break; case STATE_LOAD_PASSWORD: /* todo: this will be the 0xc0 command, but it's not handled as a command yet. */ verboselog( machine, 1, "x76f100(%d) goto start\n", chip ); break; case STATE_READ_DATA: verboselog( machine, 1, "x76f100(%d) continue reading??\n", chip ); // verboselog( machine, 1, "x76f100(%d) goto load address\n", chip ); // c->state = STATE_LOAD_ADDRESS; break; default: verboselog( machine, 1, "x76f100(%d) skipped start (default)\n", chip ); break; } c->bit = 0; c->byte = 0; c->shift = 0; c->sdar = 0; } } c->sdaw = sda; } int x76f100_sda_read( running_machine *machine, int chip ) { struct x76f100_chip *c; if( chip >= X76F100_MAXCHIP ) { verboselog( machine, 0, "x76f100_sda_read( %d ) chip out of range\n", chip ); return 1; } c = &x76f100[ chip ]; if( c->cs != 0 ) { verboselog( machine, 2, "x76f100(%d) not selected\n", chip ); return 1; } verboselog( machine, 2, "x76f100(%d) sdar=%d\n", chip, c->sdar ); return c->sdar; } static void nvram_handler_x76f100( running_machine *machine, mame_file *file, int read_or_write, int chip ) { struct x76f100_chip *c; if( chip >= X76F100_MAXCHIP ) { verboselog( machine, 0, "nvram_handler_x76f100( %d ) chip out of range\n", chip ); return; } c = &x76f100[ chip ]; if( read_or_write ) { mame_fwrite( file, c->write_password, SIZE_WRITE_PASSWORD ); mame_fwrite( file, c->read_password, SIZE_READ_PASSWORD ); mame_fwrite( file, c->data, SIZE_DATA ); } else if( file ) { mame_fread( file, c->write_password, SIZE_WRITE_PASSWORD ); mame_fread( file, c->read_password, SIZE_READ_PASSWORD ); mame_fread( file, c->data, SIZE_DATA ); } } NVRAM_HANDLER( x76f100_0 ) { nvram_handler_x76f100( machine, file, read_or_write, 0 ); } NVRAM_HANDLER( x76f100_1 ) { nvram_handler_x76f100( machine, file, read_or_write, 1 ); }