2 * $Id: bios.c,v 1.1 2006-01-22 22:40:53 nkeynes Exp $
4 * "Fake" BIOS functions, for operation without the actual BIOS.
6 * Copyright (c) 2005 Nathan Keynes.
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
22 #include "sh4/sh4core.h"
24 #define COMMAND_QUEUE_LENGTH 16
26 /* TODO: Check if these are the real ATAPI command codes or not */
27 #define GD_CMD_PIOREAD 16
28 #define GD_CMD_DMAREAD 17
29 #define GD_CMD_GETTOC 18
30 #define GD_CMD_GETTOC2 19
31 #define GD_CMD_PLAY 20
32 #define GD_CMD_PLAY2 21
33 #define GD_CMD_PAUSE 22
34 #define GD_CMD_RELEASE 23
35 #define GD_CMD_INIT 24
36 #define GD_CMD_SEEK 27
37 #define GD_CMD_READ 28
38 #define GD_CMD_STOP 33
39 #define GD_CMD_GETSCD 34
40 #define GD_CMD_GETSES 35
42 #define GD_CMD_STATUS_NONE 0
43 #define GD_CMD_STATUS_ACTIVE 1
44 #define GD_CMD_STATUS_DONE 2
45 #define GD_CMD_STATUS_ABORT 3
46 #define GD_CMD_STATUS_ERROR 4
49 #define GD_ERROR_NO_DISC 2
50 #define GD_ERROR_DISC_CHANGE 6
51 #define GD_ERROR_SYSTEM 1
54 typedef struct gdrom_command {
61 static struct gdrom_command gdrom_cmd_queue[COMMAND_QUEUE_LENGTH];
63 static struct bios_gdrom_status {
68 void bios_gdrom_run_command( gdrom_command_t cmd )
70 DEBUG( "BIOS GD command %d", cmd->cmd_code );
71 switch( cmd->cmd_code ) {
74 cmd->status = GD_CMD_STATUS_DONE;
77 cmd->status = GD_CMD_STATUS_ERROR;
78 cmd->result[0] = GD_ERROR_SYSTEM;
83 void bios_gdrom_init( void )
85 memset( &gdrom_cmd_queue, 0, sizeof(gdrom_cmd_queue) );
88 uint32_t bios_gdrom_enqueue( uint32_t cmd, char *ptr )
91 for( i=0; i<COMMAND_QUEUE_LENGTH; i++ ) {
92 if( gdrom_cmd_queue[i].status != GD_CMD_STATUS_ACTIVE ) {
93 gdrom_cmd_queue[i].status = GD_CMD_STATUS_ACTIVE;
94 gdrom_cmd_queue[i].cmd_code = cmd;
95 gdrom_cmd_queue[i].data = ptr;
102 void bios_gdrom_run_queue( void )
105 for( i=0; i<COMMAND_QUEUE_LENGTH; i++ ) {
106 if( gdrom_cmd_queue[i].status == GD_CMD_STATUS_ACTIVE ) {
107 bios_gdrom_run_command( &gdrom_cmd_queue[i] );
112 gdrom_command_t bios_gdrom_get_command( uint32_t id )
114 if( id >= COMMAND_QUEUE_LENGTH ||
115 gdrom_cmd_queue[id].status == GD_CMD_STATUS_NONE )
117 return &gdrom_cmd_queue[id];
120 void bios_install( void )
123 sh4_write_long( 0x8C0000B0, 0xFFFFFFB0 );
124 sh4_write_long( 0x8C0000B4, 0xFFFFFFB4 );
125 sh4_write_long( 0x8C0000B8, 0xFFFFFFB8 );
126 sh4_write_long( 0x8C0000BC, 0xFFFFFFBC );
127 sh4_write_long( 0x8C0000E0, 0xFFFFFFE0 );
131 * Syscall list courtesy of Marcus Comstedt
134 void bios_syscall( uint32_t syscallid )
138 switch( syscallid ) {
139 case 0xB0: /* sysinfo */
141 case 0xB4: /* Font */
143 case 0xB8: /* Flash */
145 case 0xBC: /* Misc/GD-Rom */
146 switch( sh4r.r[6] ) {
148 switch( sh4r.r[7] ) {
149 case 0: /* Send command */
151 sh4r.r[0] = bios_gdrom_enqueue( sh4r.r[4], NULL );
153 sh4r.r[0] = bios_gdrom_enqueue( sh4r.r[4], mem_get_region(sh4r.r[5]) );
155 case 1: /* Check command */
156 cmd = bios_gdrom_get_command( sh4r.r[4] );
158 sh4r.r[0] = GD_CMD_STATUS_NONE;
160 sh4r.r[0] = cmd->status;
161 if( cmd->status == GD_CMD_STATUS_ERROR &&
163 mem_copy_to_sh4( sh4r.r[5], &cmd->result, sizeof(cmd->result) );
167 case 2: /* Mainloop */
168 bios_gdrom_run_queue();
173 case 4: /* Drive status */
174 if( sh4r.r[4] != 0 ) {
175 mem_copy_to_sh4( sh4r.r[4], &bios_gdrom_status,
176 sizeof(bios_gdrom_status) );
180 case 8: /* Abort command */
181 cmd = bios_gdrom_get_command( sh4r.r[4] );
182 if( cmd == NULL || cmd->status != GD_CMD_STATUS_ACTIVE ) {
185 cmd->status = GD_CMD_STATUS_ABORT;
191 case 10: /* Set mode */
202 case 0xE0: /* Menu */
203 switch( sh4r.r[7] ) {
205 WARN( "Entering main program" );
208 WARN( "Program aborted to DC menu");
.