Search
lxdream.org :: lxdream/src/dreamcast.c
lxdream 0.9.1
released Jun 29
Download Now
filename src/dreamcast.c
changeset 450:207461e79f21
prev422:61a0598e07ff
next461:63d4de8dcec6
author nkeynes
date Sun Oct 21 05:31:07 2007 +0000 (13 years ago)
permissions -rw-r--r--
last change Rename mmr_win.c to mmio_win.c
view annotate diff log raw
     1 /**
     2  * $Id: dreamcast.c,v 1.24 2007-10-17 11:26:45 nkeynes Exp $
     3  * Central switchboard for the system. This pulls all the individual modules
     4  * together into some kind of coherent structure. This is also where you'd
     5  * add Naomi support, if I ever get a board to play with...
     6  *
     7  * Copyright (c) 2005 Nathan Keynes.
     8  *
     9  * This program is free software; you can redistribute it and/or modify
    10  * it under the terms of the GNU General Public License as published by
    11  * the Free Software Foundation; either version 2 of the License, or
    12  * (at your option) any later version.
    13  *
    14  * This program is distributed in the hope that it will be useful,
    15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
    16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    17  * GNU General Public License for more details.
    18  */
    20 #include <errno.h>
    21 #include "dream.h"
    22 #include "config.h"
    23 #include "mem.h"
    24 #include "aica/aica.h"
    25 #include "asic.h"
    26 #include "dreamcast.h"
    27 #include "gdrom/ide.h"
    28 #include "maple/maple.h"
    30 /**
    31  * Current state of the DC virtual machine
    32  */
    33 #define STATE_UNINIT 0
    34 #define STATE_RUNNING 1
    35 #define STATE_STOPPING 2
    36 #define STATE_STOPPED 3 
    37 static volatile int dreamcast_state = STATE_UNINIT;
    38 static uint32_t timeslice_length = DEFAULT_TIMESLICE_LENGTH;
    39 const char *dreamcast_config = "DEFAULT";
    41 #define MAX_MODULES 32
    42 static int num_modules = 0;
    43 dreamcast_module_t modules[MAX_MODULES];
    45 /**
    46  * The unknown module is used for logging files without an actual module
    47  * declaration
    48  */
    49 struct dreamcast_module unknown_module = { "****", NULL, NULL, NULL, NULL, 
    50 					   NULL, NULL, NULL };
    52 /**
    53  * This function is responsible for defining how all the pieces of the
    54  * dreamcast actually fit together. 
    55  *
    56  * Note currently the locations of the various MMIO pages are hard coded in
    57  * the MMIO definitions - they should probably be moved here.
    58  */
    59 void dreamcast_configure( )
    60 {
    61     dreamcast_register_module( &eventq_module );
    62     /* Register the memory framework */
    63     dreamcast_register_module( &mem_module );
    65     /* Setup standard memory map */
    66     mem_create_repeating_ram_region( 0x0C000000, 16 MB, MEM_REGION_MAIN, 0x01000000, 0x0F000000 );
    67     mem_create_ram_region( 0x00800000, 2 MB, MEM_REGION_AUDIO );
    68     mem_create_ram_region( 0x00703000, 8 KB, MEM_REGION_AUDIO_SCRATCH );
    69     mem_create_ram_region( 0x05000000, 8 MB, MEM_REGION_VIDEO );
    70     if( mem_load_rom( lxdream_get_config_value(CONFIG_BIOS_PATH),
    71 		      0x00000000, 0x00200000, 0x89f2b1a1 ) == NULL ) {
    72 	/* Bios wasn't found. Dump an empty ram region in there for something to do */
    73 	mem_create_ram_region( 0x00000000, 0x00200000, MEM_REGION_BIOS );
    74     }
    75     mem_create_ram_region( 0x00200000, 0x00020000, MEM_REGION_FLASH );
    76     mem_load_block( lxdream_get_config_value(CONFIG_FLASH_PATH),
    77 		    0x00200000, 0x00020000 );
    79     /* Load in the rest of the core modules */
    80     dreamcast_register_module( &sh4_module );
    81     dreamcast_register_module( &asic_module );
    82     dreamcast_register_module( &pvr2_module );
    83     dreamcast_register_module( &aica_module );
    84     dreamcast_register_module( &maple_module );
    85     dreamcast_register_module( &ide_module );
    86 }
    88 void dreamcast_save_flash()
    89 {
    90     const char *file = lxdream_get_config_value(CONFIG_FLASH_PATH);
    91     mem_save_block( file, 0x00200000, 0x00020000 );
    92 }
    94 /**
    95  * Constructs a system configuration for the AICA in standalone mode,
    96  * ie sound chip only.
    97  */
    98 void dreamcast_configure_aica_only( )
    99 {
   100     dreamcast_register_module( &mem_module );
   101     mem_create_ram_region( 0x00800000, 2 MB, MEM_REGION_AUDIO );
   102     mem_create_ram_region( 0x00703000, 8 KB, MEM_REGION_AUDIO_SCRATCH );
   103     dreamcast_register_module( &aica_module );
   104     aica_enable();
   105     dreamcast_state = STATE_STOPPED;
   106 }
   108 void dreamcast_register_module( dreamcast_module_t module ) 
   109 {
   110     modules[num_modules++] = module;
   111     if( module->init != NULL )
   112 	module->init();
   113 }
   116 void dreamcast_init( void )
   117 {
   118     dreamcast_configure();
   119     dreamcast_state = STATE_STOPPED;
   120 }
   122 void dreamcast_reset( void )
   123 {
   124     int i;
   125     for( i=0; i<num_modules; i++ ) {
   126 	if( modules[i]->reset != NULL )
   127 	    modules[i]->reset();
   128     }
   129 }
   131 void dreamcast_run( void )
   132 {
   133     int i;
   134     if( dreamcast_state != STATE_RUNNING ) {
   135 	for( i=0; i<num_modules; i++ ) {
   136 	    if( modules[i]->start != NULL )
   137 		modules[i]->start();
   138 	}
   139     }
   140     dreamcast_state = STATE_RUNNING;
   141     while( dreamcast_state == STATE_RUNNING ) {
   142 	int time_to_run = timeslice_length;
   143 	for( i=0; i<num_modules; i++ ) {
   144 	    if( modules[i]->run_time_slice != NULL )
   145 		time_to_run = modules[i]->run_time_slice( time_to_run );
   146 	}
   148     }
   150     for( i=0; i<num_modules; i++ ) {
   151 	if( modules[i]->stop != NULL )
   152 	    modules[i]->stop();
   153     }
   154     dreamcast_state = STATE_STOPPED;
   155 }
   157 void dreamcast_run_for( unsigned int seconds, unsigned int nanosecs )
   158 {
   160     int i;
   161     if( dreamcast_state != STATE_RUNNING ) {
   162 	for( i=0; i<num_modules; i++ ) {
   163 	    if( modules[i]->start != NULL )
   164 		modules[i]->start();
   165 	}
   166     }
   167     dreamcast_state = STATE_RUNNING;
   168     uint32_t nanos = 0;
   169     if( nanosecs != 0 ) {
   170         nanos = 1000000000 - nanosecs;
   171 	seconds++;
   172     }
   173     while( dreamcast_state == STATE_RUNNING && seconds != 0 ) {
   174 	int time_to_run = timeslice_length;
   175 	for( i=0; i<num_modules; i++ ) {
   176 	    if( modules[i]->run_time_slice != NULL )
   177 		time_to_run = modules[i]->run_time_slice( time_to_run );
   178 	}
   179 	nanos += time_to_run;
   180 	if( nanos >= 1000000000 ) {
   181 	    nanos -= 1000000000;
   182 	    seconds--;
   183 	}
   184     }
   186     for( i=0; i<num_modules; i++ ) {
   187 	if( modules[i]->stop != NULL )
   188 	    modules[i]->stop();
   189     }
   190     dreamcast_state = STATE_STOPPED;
   191 }
   193 void dreamcast_stop( void )
   194 {
   195     if( dreamcast_state == STATE_RUNNING )
   196 	dreamcast_state = STATE_STOPPING;
   197 }
   199 void dreamcast_shutdown()
   200 {
   201     dreamcast_stop();
   202     dreamcast_save_flash();
   203 }
   205 gboolean dreamcast_is_running( void )
   206 {
   207     return dreamcast_state == STATE_RUNNING;
   208 }
   210 /********************************* Save States *****************************/
   212 struct save_state_header {
   213     char magic[16];
   214     uint32_t version;
   215     uint32_t module_count;
   216 };
   218 int dreamcast_load_state( const gchar *filename )
   219 {
   220     int i,j;
   221     uint32_t len;
   222     int have_read[MAX_MODULES];
   223     char tmp[64];
   224     struct save_state_header header;
   225     FILE *f;
   227     f = fopen( filename, "r" );
   228     if( f == NULL ) return errno;
   230     fread( &header, sizeof(header), 1, f );
   231     if( strncmp( header.magic, DREAMCAST_SAVE_MAGIC, 16 ) != 0 ) {
   232 	ERROR( "Not a %s save state file", APP_NAME );
   233 	return 1;
   234     }
   235     if( header.version != DREAMCAST_SAVE_VERSION ) {
   236 	ERROR( "%s save state version not supported", APP_NAME );
   237 	return 1;
   238     }
   239     if( header.module_count > MAX_MODULES ) {
   240 	ERROR( "%s save state is corrupted (bad module count)", APP_NAME );
   241 	return 1;
   242     }
   243     for( i=0; i<MAX_MODULES; i++ ) {
   244 	have_read[i] = 0;
   245     }
   247     for( i=0; i<header.module_count; i++ ) {
   248 	fread(tmp, 4, 1, f );
   249 	if( strncmp(tmp, "BLCK", 4) != 0 ) {
   250 	    ERROR( "%s save state is corrupted (missing block header %d)", APP_NAME, i );
   251 	    return 2;
   252 	}
   253 	len = fread_string(tmp, sizeof(tmp), f );
   254 	if( len > 64 || len < 1 ) {
   255 	    ERROR( "%s save state is corrupted (bad string)", APP_NAME );
   256 	    return 2;
   257 	}
   259 	/* Find the matching module by name */
   260 	for( j=0; j<num_modules; j++ ) {
   261 	    if( strcmp(modules[j]->name,tmp) == 0 ) {
   262 		have_read[j] = 1;
   263 		if( modules[j]->load == NULL ) {
   264 		    ERROR( "%s save state is corrupted (no loader for %s)", APP_NAME, modules[j]->name );
   265 		    return 2;
   266 		} else if( modules[j]->load(f) != 0 ) {
   267 		    ERROR( "%s save state is corrupted (%s failed)", APP_NAME, modules[j]->name );
   268 		    return 2;
   269 		}
   270 		break;
   271 	    }
   272 	}
   273 	if( j == num_modules ) {
   274 	    ERROR( "%s save state contains unrecognized section", APP_NAME );
   275 	    return 2;
   276 	}
   277     }
   279     /* Any modules that we didn't load - reset to the default state.
   280      * (ie it's not an error to skip a module if you don't actually
   281      * care about its state).
   282      */
   283     for( j=0; j<num_modules; j++ ) {
   284 	if( have_read[j] == 0 && modules[j]->reset != NULL ) {
   285 	    modules[j]->reset();
   286 	}
   287     }
   288     fclose(f);
   289     INFO( "Save state read from %s", filename );
   290     return 0;
   291 }
   293 int dreamcast_save_state( const gchar *filename )
   294 {
   295     int i;
   296     FILE *f;
   297     struct save_state_header header;
   299     f = fopen( filename, "w" );
   300     if( f == NULL )
   301 	return errno;
   302     strcpy( header.magic, DREAMCAST_SAVE_MAGIC );
   303     header.version = DREAMCAST_SAVE_VERSION;
   304     header.module_count = 0;
   306     for( i=0; i<num_modules; i++ ) {
   307 	if( modules[i]->save != NULL )
   308 	    header.module_count++;
   309     }
   310     fwrite( &header, sizeof(header), 1, f );
   311     for( i=0; i<num_modules; i++ ) {
   312 	if( modules[i]->save != NULL ) {
   313 	    fwrite( "BLCK", 4, 1, f );
   314 	    fwrite_string( modules[i]->name, f );
   315 	    modules[i]->save(f);
   316 	}
   317     }
   318     fclose( f );
   319     INFO( "Save state written to %s", filename );
   320     return 0;
   321 }
.