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| 1 | +/* |
| 2 | + * Copyright (C) 2015 Michael Brown <mbrown@fensystems.co.uk>. |
| 3 | + * |
| 4 | + * This program is free software; you can redistribute it and/or |
| 5 | + * modify it under the terms of the GNU General Public License as |
| 6 | + * published by the Free Software Foundation; either version 2 of the |
| 7 | + * License, or (at your option) any later version. |
| 8 | + * |
| 9 | + * This program is distributed in the hope that it will be useful, but |
| 10 | + * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 12 | + * General Public License for more details. |
| 13 | + * |
| 14 | + * You should have received a copy of the GNU General Public License |
| 15 | + * along with this program; if not, write to the Free Software |
| 16 | + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 17 | + * 02110-1301, USA. |
| 18 | + * |
| 19 | + * You can also choose to distribute this program under the terms of |
| 20 | + * the Unmodified Binary Distribution Licence (as given in the file |
| 21 | + * COPYING.UBDL), provided that you have satisfied its requirements. |
| 22 | + */ |
| 23 | + |
| 24 | +FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL ); |
| 25 | + |
| 26 | +#include <stdint.h> |
| 27 | +#include <string.h> |
| 28 | +#include <errno.h> |
| 29 | +#include <ipxe/console.h> |
| 30 | +#include <ipxe/init.h> |
| 31 | +#include <realmode.h> |
| 32 | +#include <int13.h> |
| 33 | +#include <config/console.h> |
| 34 | + |
| 35 | +/** @file |
| 36 | + * |
| 37 | + * INT13 disk log console |
| 38 | + * |
| 39 | + */ |
| 40 | + |
| 41 | +/* Set default console usage if applicable */ |
| 42 | +#if ! ( defined ( CONSOLE_INT13 ) && CONSOLE_EXPLICIT ( CONSOLE_INT13 ) ) |
| 43 | +#undef CONSOLE_INT13 |
| 44 | +#define CONSOLE_INT13 ( CONSOLE_USAGE_ALL & ~CONSOLE_USAGE_LOG ) |
| 45 | +#endif |
| 46 | + |
| 47 | +/** Disk drive number */ |
| 48 | +#define INT13CON_DRIVE 0x80 |
| 49 | + |
| 50 | +/** Log partition type */ |
| 51 | +#define INT13CON_PARTITION_TYPE 0xe0 |
| 52 | + |
| 53 | +/** Maximum number of outstanding unwritten characters */ |
| 54 | +#define INT13CON_MAX_UNWRITTEN 64 |
| 55 | + |
| 56 | +/** Log partition header */ |
| 57 | +struct int13con_header { |
| 58 | + /** Magic signature */ |
| 59 | + char magic[10]; |
| 60 | +} __attribute__ (( packed )); |
| 61 | + |
| 62 | +/** Log partition magic signature */ |
| 63 | +#define INT13CON_MAGIC "iPXE LOG\n\n" |
| 64 | + |
| 65 | +/** Sector buffer */ |
| 66 | +static uint8_t __bss16_array ( int13con_buffer, [INT13_BLKSIZE] ); |
| 67 | +#define int13con_buffer __use_data16 ( int13con_buffer ) |
| 68 | + |
| 69 | +/** Disk address packet */ |
| 70 | +static struct int13_disk_address __bss16 ( int13con_address ); |
| 71 | +#define int13con_address __use_data16 ( int13con_address ) |
| 72 | + |
| 73 | +/** Current LBA */ |
| 74 | +static uint64_t int13con_lba; |
| 75 | + |
| 76 | +/** Maximum LBA */ |
| 77 | +static uint64_t int13con_max_lba; |
| 78 | + |
| 79 | +/** Current offset within sector */ |
| 80 | +static size_t int13con_offset; |
| 81 | + |
| 82 | +/** Number of unwritten characters */ |
| 83 | +static size_t int13con_unwritten; |
| 84 | + |
| 85 | +struct console_driver int13con __console_driver; |
| 86 | + |
| 87 | +/** |
| 88 | + * Read/write disk sector |
| 89 | + * |
| 90 | + * @v op Operation |
| 91 | + * @v lba Logical block address |
| 92 | + * @ret rc Return status code |
| 93 | + */ |
| 94 | +static int int13con_rw ( unsigned int op, uint64_t lba ) { |
| 95 | + uint8_t error; |
| 96 | + |
| 97 | + /* Construct disk address packet */ |
| 98 | + int13con_address.bufsize = sizeof ( int13con_address ); |
| 99 | + int13con_address.count = 1; |
| 100 | + int13con_address.buffer.segment = rm_ds; |
| 101 | + int13con_address.buffer.offset = __from_data16 ( int13con_buffer ); |
| 102 | + int13con_address.lba = lba; |
| 103 | + |
| 104 | + /* Issue INT13 */ |
| 105 | + __asm__ ( REAL_CODE ( "int $0x13\n\t" ) |
| 106 | + : "=a" ( error ) |
| 107 | + : "0" ( op << 8 ), "d" ( INT13CON_DRIVE ), |
| 108 | + "S" ( __from_data16 ( &int13con_address ) ) ); |
| 109 | + if ( error ) { |
| 110 | + DBG ( "INT13CON operation %04x failed: %02x\n", |
| 111 | + op, error ); |
| 112 | + return -EIO; |
| 113 | + } |
| 114 | + |
| 115 | + return 0; |
| 116 | +} |
| 117 | + |
| 118 | +/** |
| 119 | + * Write character to console |
| 120 | + * |
| 121 | + * @v character Character |
| 122 | + */ |
| 123 | +static void int13con_putchar ( int character ) { |
| 124 | + static int busy; |
| 125 | + int rc; |
| 126 | + |
| 127 | + /* Ignore if we are already mid-logging */ |
| 128 | + if ( busy ) |
| 129 | + return; |
| 130 | + busy = 1; |
| 131 | + |
| 132 | + /* Write character to buffer */ |
| 133 | + int13con_buffer[int13con_offset++] = character; |
| 134 | + int13con_unwritten++; |
| 135 | + |
| 136 | + /* Write sector to disk, if applicable */ |
| 137 | + if ( ( int13con_offset == INT13_BLKSIZE ) || |
| 138 | + ( int13con_unwritten == INT13CON_MAX_UNWRITTEN ) || |
| 139 | + ( character == '\n' ) ) { |
| 140 | + |
| 141 | + /* Write sector to disk */ |
| 142 | + if ( ( rc = int13con_rw ( INT13_EXTENDED_WRITE, |
| 143 | + int13con_lba ) ) != 0 ) { |
| 144 | + DBG ( "INT13CON could not write log\n" ); |
| 145 | + /* Ignore and continue; there's nothing we can do */ |
| 146 | + } |
| 147 | + |
| 148 | + /* Reset count of unwritten characters */ |
| 149 | + int13con_unwritten = 0; |
| 150 | + } |
| 151 | + |
| 152 | + /* Move to next sector, if applicable */ |
| 153 | + if ( int13con_offset == INT13_BLKSIZE ) { |
| 154 | + |
| 155 | + /* Disable console if we have run out of space */ |
| 156 | + if ( int13con_lba >= int13con_max_lba ) |
| 157 | + int13con.disabled = 1; |
| 158 | + |
| 159 | + /* Clear log buffer */ |
| 160 | + memset ( int13con_buffer, 0, sizeof ( int13con_buffer ) ); |
| 161 | + int13con_offset = 0; |
| 162 | + |
| 163 | + /* Move to next sector */ |
| 164 | + int13con_lba++; |
| 165 | + } |
| 166 | + |
| 167 | + /* Clear busy flag */ |
| 168 | + busy = 0; |
| 169 | +} |
| 170 | + |
| 171 | +/** |
| 172 | + * Find log partition |
| 173 | + * |
| 174 | + * @ret rc Return status code |
| 175 | + */ |
| 176 | +static int int13con_find ( void ) { |
| 177 | + struct master_boot_record *mbr = |
| 178 | + ( ( struct master_boot_record * ) int13con_buffer ); |
| 179 | + struct int13con_header *hdr = |
| 180 | + ( ( struct int13con_header * ) int13con_buffer ); |
| 181 | + struct partition_table_entry part[4]; |
| 182 | + unsigned int i; |
| 183 | + int rc; |
| 184 | + |
| 185 | + /* Read MBR */ |
| 186 | + if ( ( rc = int13con_rw ( INT13_EXTENDED_READ, 0 ) ) != 0 ) { |
| 187 | + DBG ( "INT13CON could not read MBR: %s\n", strerror ( rc ) ); |
| 188 | + return rc; |
| 189 | + } |
| 190 | + |
| 191 | + /* Check MBR magic */ |
| 192 | + if ( mbr->magic != INT13_MBR_MAGIC ) { |
| 193 | + DBG ( "INT13CON incorrect MBR magic\n" ); |
| 194 | + DBG2_HDA ( 0, mbr, sizeof ( *mbr ) ); |
| 195 | + return -EINVAL; |
| 196 | + } |
| 197 | + |
| 198 | + /* Look for magic partition */ |
| 199 | + memcpy ( part, mbr->partitions, sizeof ( part ) ); |
| 200 | + for ( i = 0 ; i < ( sizeof ( part ) / sizeof ( part[0] ) ) ; i++ ) { |
| 201 | + |
| 202 | + /* Skip partitions of the wrong type */ |
| 203 | + if ( part[i].type != INT13CON_PARTITION_TYPE ) |
| 204 | + continue; |
| 205 | + |
| 206 | + /* Read partition header */ |
| 207 | + if ( ( rc = int13con_rw ( INT13_EXTENDED_READ, |
| 208 | + part[i].start ) ) != 0 ) { |
| 209 | + DBG ( "INT13CON partition %d could not read header: " |
| 210 | + "%s\n", ( i + 1 ), strerror ( rc ) ); |
| 211 | + continue; |
| 212 | + } |
| 213 | + |
| 214 | + /* Check partition header */ |
| 215 | + if ( memcmp ( hdr->magic, INT13CON_MAGIC, |
| 216 | + sizeof ( hdr->magic ) ) != 0 ) { |
| 217 | + DBG ( "INT13CON partition %d bad magic\n", ( i + 1 ) ); |
| 218 | + DBG2_HDA ( 0, hdr, sizeof ( *hdr ) ); |
| 219 | + continue; |
| 220 | + } |
| 221 | + |
| 222 | + /* Found log partition */ |
| 223 | + DBG ( "INT13CON partition %d at [%08x,%08x)\n", ( i + 1 ), |
| 224 | + part[i].start, ( part[i].start + part[i].length ) ); |
| 225 | + int13con_lba = part[i].start; |
| 226 | + int13con_max_lba = ( part[i].start + part[i].length - 1 ); |
| 227 | + |
| 228 | + /* Initialise log buffer */ |
| 229 | + memset ( &int13con_buffer[ sizeof ( *hdr ) ], 0, |
| 230 | + ( sizeof ( int13con_buffer ) - sizeof ( *hdr ) ) ); |
| 231 | + int13con_offset = sizeof ( hdr->magic ); |
| 232 | + |
| 233 | + return 0; |
| 234 | + } |
| 235 | + |
| 236 | + DBG ( "INT13CON found no log partition\n" ); |
| 237 | + return -ENOENT; |
| 238 | +} |
| 239 | + |
| 240 | +/** |
| 241 | + * Initialise INT13 console |
| 242 | + * |
| 243 | + */ |
| 244 | +static void int13con_init ( void ) { |
| 245 | + uint8_t error; |
| 246 | + uint16_t check; |
| 247 | + unsigned int discard_c; |
| 248 | + unsigned int discard_d; |
| 249 | + int rc; |
| 250 | + |
| 251 | + /* Check for INT13 extensions */ |
| 252 | + __asm__ __volatile__ ( REAL_CODE ( "int $0x13\n\t" |
| 253 | + "setc %%al\n\t" ) |
| 254 | + : "=a" ( error ), "=b" ( check ), |
| 255 | + "=c" ( discard_c ), "=d" ( discard_d ) |
| 256 | + : "0" ( INT13_EXTENSION_CHECK << 8 ), |
| 257 | + "1" ( 0x55aa ), "3" ( INT13CON_DRIVE ) ); |
| 258 | + if ( error || ( check != 0xaa55 ) ) { |
| 259 | + DBG ( "INT13CON missing extensions (%02x,%04x)\n", |
| 260 | + error, check ); |
| 261 | + return; |
| 262 | + } |
| 263 | + |
| 264 | + /* Locate log partition */ |
| 265 | + if ( ( rc = int13con_find() ) != 0) |
| 266 | + return; |
| 267 | + |
| 268 | + /* Enable console */ |
| 269 | + int13con.disabled = 0; |
| 270 | +} |
| 271 | + |
| 272 | +/** |
| 273 | + * INT13 console initialisation function |
| 274 | + */ |
| 275 | +struct init_fn int13con_init_fn __init_fn ( INIT_CONSOLE ) = { |
| 276 | + .initialise = int13con_init, |
| 277 | +}; |
| 278 | + |
| 279 | +/** INT13 console driver */ |
| 280 | +struct console_driver int13con __console_driver = { |
| 281 | + .putchar = int13con_putchar, |
| 282 | + .disabled = CONSOLE_DISABLED, |
| 283 | + .usage = CONSOLE_INT13, |
| 284 | +}; |
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