lxdream.org :: lxdream/src/gdrom/ide.c r47:da09bcb7ce69

tree revision 47:da09bcb7ce69

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     1 /**

     2  * $Id: ide.c,v 1.7 2005-12-27 12:41:33 nkeynes Exp $

     3  *

     4  * IDE interface implementation

     5  *

     6  * Copyright (c) 2005 Nathan Keynes.

     7  *

     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.

    12  *

    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.

    17  */

    19 #define MODULE ide_module

    21 #include <stdlib.h>

    22 #include "dream.h"

    23 #include "gdrom/ide.h"

    25 #define MAX_WRITE_BUF 4096;

    27 void ide_init( void );

    28 void ide_init( void );

    30 struct dreamcast_module ide_module = { "IDE", ide_init, ide_reset, NULL, NULL,

    31 				       NULL, NULL, NULL };

    33 struct ide_registers idereg;

    35 static char command_buffer[12];

    37 /* "\0\0\0\0\xb4\x19\0\0\x08SE      REV 6.42990316" */

    38 char gdrom_ident[] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0xb4, 0x19, 0x00,

    39                        0x00, 0x08, 0x53, 0x45, 0x20, 0x20, 0x20, 0x20,

    40                        0x20, 0x20, 0x52, 0x65, 0x76, 0x20, 0x36, 0x2e,

    41                        0x34, 0x32, 0x39, 0x39, 0x30, 0x33, 0x31, 0x36 };

    44 void set_write_buffer( char *buf, int len )

    45 {

    46     idereg.status |= IDE_ST_DATA;

    47     idereg.data = buf;

    48     idereg.datalen = len;

    49     idereg.writeptr = (uint16_t *)buf;

    50     idereg.readptr = NULL;

    51 }

    53 void set_read_buffer( char *buf, int len )

    54 {

    55     idereg.status |= IDE_ST_DATA;

    56     idereg.data = buf;

    57     idereg.datalen = len;

    58     idereg.readptr = (uint16_t *)buf;

    59     idereg.writeptr = NULL;

    60     idereg.lba1 = len&0xFF;

    61     idereg.lba2 = len>>8;

    62 }

    64 void ide_clear_interrupt( void )

    65 {

    66     /* TODO */

    67 }

    69 void ide_init( void )

    70 {

    72 }

    74 void ide_reset( void )

    75 {

    76     ide_clear_interrupt();

    77     idereg.error = 0x01;

    78     idereg.count = 0x01;

    79     idereg.lba0 = 0x21;

    80     idereg.lba1 = 0x14;

    81     idereg.lba2 = 0xeb;

    82     idereg.feature = 0; /* Indeterminate really */

    83     idereg.status = 0x00;

    84     idereg.device = 0x00;

    85     idereg.disc = IDE_DISC_GDROM | IDE_DISC_READY;

    86 }

    88 uint16_t ide_read_data_pio( void ) {

    89     if( idereg.readptr == NULL )

    90         return 0xFFFF;

    91     uint16_t rv = *idereg.readptr++;

    92     idereg.datalen-=2;

    93     if( idereg.datalen <=0 ) {

    94         idereg.readptr = NULL;

    95         idereg.status &= ~IDE_ST_DATA;

    96     }

    97     return rv;

    98 }

   100 void ide_write_data_pio( uint16_t val ) {

   101     if( idereg.writeptr == NULL )

   102         return;

   103     *idereg.writeptr++ = val;

   104     idereg.datalen-=2;

   105     if( idereg.datalen <= 0 ) {

   106         idereg.writeptr = NULL;

   107         idereg.status &= ~IDE_ST_DATA;

   108         ide_write_buffer( idereg.data );

   109     }

   110 }

   112 void ide_write_control( uint8_t val ) {

   113     /* TODO: In theory we can cause a soft-reset here, but the DC doesn't

   114      * appear to support it.

   115      */

   116 }

   118 void ide_write_command( uint8_t val ) {

   119     idereg.command = val;

   120     switch( val ) {

   121     case IDE_CMD_RESET_DEVICE:

   122 	ide_reset();

   123 	break;

   124     case IDE_CMD_PACKET:

   125 	set_write_buffer(command_buffer,12);

   126 	break;

   127     case IDE_CMD_SET_FEATURE:

   128 	switch( idereg.feature ) {

   129 	case IDE_FEAT_SET_TRANSFER_MODE:

   130 	    switch( idereg.count & 0xF8 ) {

   131 	    case IDE_XFER_PIO:

   132 		INFO( "Set PIO default mode: %d", idereg.count&0x07 );

   133 		break;

   134 	    case IDE_XFER_PIO_FLOW:

   135 		INFO( "Set PIO Flow-control mode: %d", idereg.count&0x07 );

   136 		break;

   137 	    case IDE_XFER_MULTI_DMA:

   138 		INFO( "Set Multiword DMA mode: %d", idereg.count&0x07 );

   139 		break;

   140 	    case IDE_XFER_ULTRA_DMA:

   141 		INFO( "Set Ultra DMA mode: %d", idereg.count&0x07 );

   142 		break;

   143 	    default:

   144 		INFO( "Setting unknown transfer mode: %02X", idereg.count );

   145 		break;

   146 	    }

   147 	    break;

   148 	default:

   149 	    WARN( "IDE: unimplemented feature: %02X", idereg.feature );

   150 	}

   151 	break;

   152     default:

   153 	WARN( "IDE: Unimplemented command: %02X", val );

   154     }

   155     idereg.status |= IDE_ST_READY | IDE_ST_SERV;

   156 }

   158 void ide_write_buffer( char *data ) {

   159     uint16_t length;

   160     switch( idereg.command ) {

   161         case IDE_CMD_PACKET:

   162             /* Okay we have the packet in the command buffer */

   163             WARN( "ATAPI: Received Packet command: %02X", data[0] );

   165             switch( command_buffer[0] ) {

   166                 case PKT_CMD_IDENTIFY:

   167                     /* NB: Bios sets data[4] = 0x08, no idea what this is for;

   168                      * different values here appear to have no effect.

   169                      */

   170                     length = *((uint16_t*)(data+2));

   171                     if( length > sizeof(gdrom_ident) )

   172                         length = sizeof(gdrom_ident);

   173                     set_read_buffer(gdrom_ident, length);

   174                     break;

   175             }

   176             break;

   177     }

   178 }