1.1 --- a/src/dreamcast.c	Tue Jul 21 20:33:21 2009 +1000
     1.2 +++ b/src/dreamcast.c	Fri Jun 04 09:13:40 2010 +1000
     1.3 @@ -43,6 +43,7 @@
     1.4                 STATE_STOPPING, STATE_STOPPED } dreamcast_state_t;
     1.5      
     1.6  static volatile dreamcast_state_t dreamcast_state = STATE_UNINIT;
     1.7 +static gboolean dreamcast_use_bios = TRUE;
     1.8  static gboolean dreamcast_has_bios = FALSE;
     1.9  static gboolean dreamcast_has_flash = FALSE;
    1.10  static gboolean dreamcast_exit_on_stop = FALSE;
    1.11 @@ -86,7 +87,7 @@
    1.12   * Note currently the locations of the various MMIO pages are hard coded in
    1.13   * the MMIO definitions - they should probably be moved here.
    1.14   */
    1.15 -void dreamcast_configure( )
    1.16 +void dreamcast_configure( gboolean use_bootrom )
    1.17  {
    1.18      char *bios_path = lxdream_get_global_config_path_value(CONFIG_BIOS_PATH);
    1.19      char *flash_path = lxdream_get_global_config_path_value(CONFIG_FLASH_PATH);
    1.20 @@ -108,7 +109,12 @@
    1.21      mem_map_region( NULL,            0x11000000, 16 MB,  MEM_REGION_PVR2VDMA1,    &mem_region_pvr2vdma1, 0, 16 MB, 0 );
    1.22      mem_map_region( NULL,            0x13000000, 16 MB,  MEM_REGION_PVR2VDMA2,    &mem_region_pvr2vdma2, 0, 16 MB, 0 );
    1.23      
    1.24 -    dreamcast_has_bios = mem_load_rom( dc_boot_rom, bios_path, 2 MB, 0x89f2b1a1 );
    1.25 +    dreamcast_use_bios = use_bootrom;
    1.26 +    dreamcast_has_bios = dreamcast_load_bios( bios_path );
    1.27 +    if( !dreamcast_has_bios ) {
    1.28 +        dreamcast_load_fakebios();
    1.29 +    }
    1.30 +
    1.31      if( flash_path != NULL && flash_path[0] != '\0' ) {
    1.32          mem_load_block( flash_path, 0x00200000, 0x00020000 );
    1.33      }
    1.34 @@ -128,10 +134,28 @@
    1.35  
    1.36  gboolean dreamcast_load_bios( const gchar *filename )
    1.37  {
    1.38 -    dreamcast_has_bios = mem_load_rom( dc_boot_rom, filename, 2 MB, 0x89f2b1a1 );
    1.39 +    if( dreamcast_use_bios ) {
    1.40 +        dreamcast_has_bios = mem_load_rom( dc_boot_rom, filename, 2 MB, 0x89f2b1a1 );
    1.41 +    } else {
    1.42 +        dreamcast_has_bios = FALSE;
    1.43 +    }
    1.44      return dreamcast_has_bios;
    1.45  }
    1.46  
    1.47 +static const char fakebios[] = {
    1.48 +        0x00, 0xd1, /* movl $+4, r1 */
    1.49 +        0x2b, 0x41, /* jmp @r1 */
    1.50 +        0xa0, 0xff, /* .long 0xffffffa0 */
    1.51 +        0xff, 0xff };
    1.52 +gboolean dreamcast_load_fakebios( )
    1.53 +{
    1.54 +    memset( dc_boot_rom, 0, 2 MB );
    1.55 +    memcpy( dc_boot_rom, fakebios, sizeof(fakebios) );
    1.56 +    syscall_add_hook( 0xA0, bios_boot );
    1.57 +    dreamcast_has_bios = TRUE;
    1.58 +    return TRUE;
    1.59 +}
    1.60 +
    1.61  gboolean dreamcast_load_flash( const gchar *filename )
    1.62  {
    1.63      if( filename != NULL && filename[0] != '\0' ) {
    1.64 @@ -201,9 +225,9 @@
    1.65      dreamcast_exit_on_stop = flag;
    1.66  }
    1.67  
    1.68 -void dreamcast_init( void )
    1.69 +void dreamcast_init( gboolean use_bootrom )
    1.70  {
    1.71 -    dreamcast_configure();
    1.72 +    dreamcast_configure( use_bootrom );
    1.73      dreamcast_state = STATE_STOPPED;
    1.74  }
    1.75  
    1.76 @@ -326,8 +350,7 @@
    1.77  
    1.78  gboolean dreamcast_can_run(void)
    1.79  {
    1.80 -    return dreamcast_state != STATE_UNINIT &&
    1.81 -    (dreamcast_has_bios || dreamcast_program_name != NULL);
    1.82 +    return dreamcast_state != STATE_UNINIT;
    1.83  }
    1.84  
    1.85  /********************************* Save States *****************************/