| 1 | /* This file is part of the program psim. |
| 2 | |
| 3 | Copyright (C) 1994-1997, Andrew Cagney <cagney@highland.com.au> |
| 4 | |
| 5 | This program is free software; you can redistribute it and/or modify |
| 6 | it under the terms of the GNU General Public License as published by |
| 7 | the Free Software Foundation; either version 3 of the License, or |
| 8 | (at your option) any later version. |
| 9 | |
| 10 | This program is distributed in the hope that it will be useful, |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | GNU General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU General Public License |
| 16 | along with this program; if not, see <http://www.gnu.org/licenses/>. |
| 17 | |
| 18 | */ |
| 19 | |
| 20 | |
| 21 | #ifndef _HW_DISK_C_ |
| 22 | #define _HW_DISK_C_ |
| 23 | |
| 24 | #include "device_table.h" |
| 25 | |
| 26 | #include "pk.h" |
| 27 | |
| 28 | #include <stdio.h> |
| 29 | |
| 30 | #ifdef HAVE_UNISTD_H |
| 31 | #include <unistd.h> |
| 32 | #endif |
| 33 | |
| 34 | #ifndef SEEK_SET |
| 35 | #define SEEK_SET 0 |
| 36 | #endif |
| 37 | |
| 38 | /* DEVICE |
| 39 | |
| 40 | |
| 41 | cdrom - read-only removable mass storage device |
| 42 | |
| 43 | disk - mass storage device |
| 44 | |
| 45 | floppy - removable mass storage device |
| 46 | |
| 47 | |
| 48 | DESCRIPTION |
| 49 | |
| 50 | |
| 51 | Mass storage devices such as a hard-disk or cdrom-drive are not |
| 52 | normally directly connected to the processor. Instead, these |
| 53 | devices are attached to a logical bus, such as SCSI or IDE, and |
| 54 | then a controller of that bus is made accessible to the processor. |
| 55 | |
| 56 | Reflecting this, within a device tree, mass storage devices such as |
| 57 | a <<cdrom>>, <<disk>> or <<floppy>> are created as children of of a |
| 58 | logical bus controller node (such as a SCSI or IDE interface). |
| 59 | That controller, in turn, would be made the child of a physical bus |
| 60 | node that is directly accessible to the processor. |
| 61 | |
| 62 | The above mass storage devices provide two interfaces - a logical |
| 63 | and a physical. |
| 64 | |
| 65 | At the physical level the <<device_io_...>> functions can be used |
| 66 | perform reads and writes of the raw media. The address being |
| 67 | interpreted as an offset from the start of the disk. |
| 68 | |
| 69 | At the logical level, it is possible to create an instance of the |
| 70 | disk that provides access to any of the physical media, a disk |
| 71 | partition, or even a file within a partition. The <<disk-label>> |
| 72 | package, which implements this functionality, is described |
| 73 | elsewhere. Both the Open Firmware and Moto BUG rom emulations |
| 74 | support this interface. |
| 75 | |
| 76 | Block devices such as the <<floppy>> and <<cdrom>> have removable |
| 77 | media. At the programmer level, the media can be changed using the |
| 78 | <<change_media>> ioctl. From within GDB, a <<change-media>> |
| 79 | operation can be initated by using the command. |
| 80 | |
| 81 | | (gdb) sim |
| 82 | |
| 83 | |
| 84 | PROPERTIES |
| 85 | |
| 86 | |
| 87 | file = <file-name> (required) |
| 88 | |
| 89 | The name of the file that contains an image of the disk. For |
| 90 | <<disk>> and <<floppy>> devices, the image will be opened for both |
| 91 | reading and writing. Multiple image files may be specified, the |
| 92 | second and later files being opened when <<change-media>> (with a |
| 93 | NULL file name) being specified. |
| 94 | |
| 95 | |
| 96 | block-size = <nr-bytes> (optional) |
| 97 | |
| 98 | The value is returned by the block-size method. The default value |
| 99 | is 512 bytes. |
| 100 | |
| 101 | |
| 102 | max-transfer = <nr-bytes> (optional) |
| 103 | |
| 104 | The value is returned by the max-transfer method. The default value |
| 105 | is 512 bytes. |
| 106 | |
| 107 | |
| 108 | #blocks = <nr-blocks> (optional) |
| 109 | |
| 110 | The value is returned by the #blocks method. If no value is |
| 111 | present then -1 is returned. |
| 112 | |
| 113 | |
| 114 | read-only = <anything> (optional) |
| 115 | |
| 116 | If this property is present, the disk file image is always opened |
| 117 | read-only. |
| 118 | |
| 119 | EXAMPLES |
| 120 | |
| 121 | |
| 122 | Enable tracing |
| 123 | |
| 124 | | $ psim -t 'disk-device' \ |
| 125 | |
| 126 | |
| 127 | Add a CDROM and disk to an IDE bus. Specify the host operating |
| 128 | system's cd drive as the CD-ROM image. |
| 129 | |
| 130 | | -o '/pci/ide/disk@0/file "disk-image' \ |
| 131 | | -o '/pci/ide/cdrom@1/file "/dev/cd0a' \ |
| 132 | |
| 133 | |
| 134 | As part of the code implementing a logical bus device (for instance |
| 135 | the IDE controller), locate the CDROM device and then read block |
| 136 | 47. |
| 137 | |
| 138 | | device *cdrom = device_tree_find_device(me, "cdrom"); |
| 139 | | char block[512]; |
| 140 | | device_io_read_buffer(cdrom, buf, 0, |
| 141 | 0, 47 * sizeof(block), // space, address |
| 142 | sizeof(block), NULL, 0); |
| 143 | |
| 144 | |
| 145 | Use the device instance interface to read block 47 of the file |
| 146 | called <<netbsd.elf>> on the disks default partition. Similar code |
| 147 | would be used in an operating systems pre-boot loader. |
| 148 | |
| 149 | | device_instance *netbsd = |
| 150 | | device_create_instance(root, "/pci/ide/disk:,\netbsd.elf"); |
| 151 | | char block[512]; |
| 152 | | device_instance_seek(netbsd, 0, 47 * sizeof(block)); |
| 153 | | device_instance_read(netbsd, block, sizeof(block)); |
| 154 | |
| 155 | |
| 156 | BUGS |
| 157 | |
| 158 | |
| 159 | The block device specification includes mechanisms for determining |
| 160 | the physical device characteristics - such as the disks size. |
| 161 | Currently this mechanism is not implemented. |
| 162 | |
| 163 | The functionality of this device (in particular the device instance |
| 164 | interface) depends on the implementation of <<disk-label>> package. |
| 165 | That package may not be fully implemented. |
| 166 | |
| 167 | The disk does not know its size. Hence it relies on the failure of |
| 168 | fread(), fwrite() and fseek() calls to detect errors. |
| 169 | |
| 170 | The disk size is limited by the addressable range covered by |
| 171 | unsigned_word (addr). An extension would be to instead use the |
| 172 | concatenated value space:addr. |
| 173 | |
| 174 | The method #blocks should `stat' the disk to determine the number |
| 175 | of blocks if there is no #blocks property. |
| 176 | |
| 177 | It would appear that OpenFirmware does not define a client call for |
| 178 | changing (ejecting) the media of a device. |
| 179 | |
| 180 | */ |
| 181 | |
| 182 | typedef struct _hw_disk_device { |
| 183 | int name_index; |
| 184 | int nr_names; |
| 185 | char *name; |
| 186 | int read_only; |
| 187 | /* unsigned_word size; */ |
| 188 | FILE *image; |
| 189 | } hw_disk_device; |
| 190 | |
| 191 | typedef struct _hw_disk_instance { |
| 192 | unsigned_word pos; |
| 193 | hw_disk_device *disk; |
| 194 | } hw_disk_instance; |
| 195 | |
| 196 | |
| 197 | static void |
| 198 | open_disk_image(device *me, |
| 199 | hw_disk_device *disk, |
| 200 | const char *name) |
| 201 | { |
| 202 | if (disk->image != NULL) |
| 203 | fclose(disk->image); |
| 204 | if (disk->name != NULL) |
| 205 | free(disk->name); |
| 206 | disk->name = strdup(name); |
| 207 | disk->image = fopen(disk->name, disk->read_only ? "r" : "r+"); |
| 208 | if (disk->image == NULL) { |
| 209 | perror(device_name(me)); |
| 210 | device_error(me, "open %s failed\n", disk->name); |
| 211 | } |
| 212 | |
| 213 | DTRACE(disk, ("image %s (%s)\n", |
| 214 | disk->name, |
| 215 | (disk->read_only ? "read-only" : "read-write"))); |
| 216 | } |
| 217 | |
| 218 | static void |
| 219 | hw_disk_init_address(device *me) |
| 220 | { |
| 221 | hw_disk_device *disk = device_data(me); |
| 222 | unsigned_word address; |
| 223 | int space; |
| 224 | const char *name; |
| 225 | |
| 226 | /* attach to the parent. Since the bus is logical, attach using just |
| 227 | the unit-address (size must be zero) */ |
| 228 | device_address_to_attach_address(device_parent(me), device_unit_address(me), |
| 229 | &space, &address, me); |
| 230 | device_attach_address(device_parent(me), attach_callback, |
| 231 | space, address, 0/*size*/, access_read_write_exec, |
| 232 | me); |
| 233 | |
| 234 | /* Tell the world we are a disk. */ |
| 235 | device_add_string_property(me, "device_type", "block"); |
| 236 | |
| 237 | /* get the name of the file specifying the disk image */ |
| 238 | disk->name_index = 0; |
| 239 | disk->nr_names = device_find_string_array_property(me, "file", |
| 240 | disk->name_index, &name); |
| 241 | if (!disk->nr_names) |
| 242 | device_error(me, "invalid file property"); |
| 243 | |
| 244 | /* is it a RO device? */ |
| 245 | disk->read_only = |
| 246 | (strcmp(device_name(me), "disk") != 0 |
| 247 | && strcmp(device_name(me), "floppy") != 0 |
| 248 | && device_find_property(me, "read-only") == NULL); |
| 249 | |
| 250 | /* now open it */ |
| 251 | open_disk_image(me, disk, name); |
| 252 | } |
| 253 | |
| 254 | static int |
| 255 | hw_disk_ioctl(device *me, |
| 256 | cpu *processor, |
| 257 | unsigned_word cia, |
| 258 | device_ioctl_request request, |
| 259 | va_list ap) |
| 260 | { |
| 261 | switch (request) { |
| 262 | case device_ioctl_change_media: |
| 263 | { |
| 264 | hw_disk_device *disk = device_data(me); |
| 265 | const char *name = va_arg(ap, const char *); |
| 266 | if (name != NULL) { |
| 267 | disk->name_index = -1; |
| 268 | } |
| 269 | else { |
| 270 | disk->name_index = (disk->name_index + 1) % disk->nr_names; |
| 271 | if (!device_find_string_array_property(me, "file", |
| 272 | disk->name_index, &name)) |
| 273 | device_error(me, "invalid file property"); |
| 274 | } |
| 275 | open_disk_image(me, disk, name); |
| 276 | } |
| 277 | break; |
| 278 | default: |
| 279 | device_error(me, "insupported ioctl request"); |
| 280 | break; |
| 281 | } |
| 282 | return 0; |
| 283 | } |
| 284 | |
| 285 | |
| 286 | |
| 287 | |
| 288 | |
| 289 | static unsigned |
| 290 | hw_disk_io_read_buffer(device *me, |
| 291 | void *dest, |
| 292 | int space, |
| 293 | unsigned_word addr, |
| 294 | unsigned nr_bytes, |
| 295 | cpu *processor, |
| 296 | unsigned_word cia) |
| 297 | { |
| 298 | hw_disk_device *disk = device_data(me); |
| 299 | unsigned nr_bytes_read; |
| 300 | if (space != 0) |
| 301 | device_error(me, "read - extended disk addressing unimplemented"); |
| 302 | if (nr_bytes == 0) |
| 303 | nr_bytes_read = 0; |
| 304 | else if (fseek(disk->image, addr, SEEK_SET) < 0) |
| 305 | nr_bytes_read = 0; |
| 306 | else if (fread(dest, nr_bytes, 1, disk->image) != 1) |
| 307 | nr_bytes_read = 0; |
| 308 | else |
| 309 | nr_bytes_read = nr_bytes; |
| 310 | DTRACE(disk, ("io-read - address 0x%lx, nr-bytes-read %d, requested %d\n", |
| 311 | (unsigned long) addr, (int)nr_bytes_read, (int)nr_bytes)); |
| 312 | return nr_bytes_read; |
| 313 | } |
| 314 | |
| 315 | |
| 316 | static unsigned |
| 317 | hw_disk_io_write_buffer(device *me, |
| 318 | const void *source, |
| 319 | int space, |
| 320 | unsigned_word addr, |
| 321 | unsigned nr_bytes, |
| 322 | cpu *processor, |
| 323 | unsigned_word cia) |
| 324 | { |
| 325 | hw_disk_device *disk = device_data(me); |
| 326 | unsigned nr_bytes_written; |
| 327 | if (space != 0) |
| 328 | device_error(me, "write - extended disk addressing unimplemented"); |
| 329 | if (disk->read_only) |
| 330 | nr_bytes_written = 0; |
| 331 | else if (nr_bytes == 0) |
| 332 | nr_bytes_written = 0; |
| 333 | else if (fseek(disk->image, addr, SEEK_SET) < 0) |
| 334 | nr_bytes_written = 0; |
| 335 | else if (fwrite(source, nr_bytes, 1, disk->image) != 1) |
| 336 | nr_bytes_written = 0; |
| 337 | else |
| 338 | nr_bytes_written = nr_bytes; |
| 339 | DTRACE(disk, ("io-write - address 0x%lx, nr-bytes-written %d, requested %d\n", |
| 340 | (unsigned long) addr, (int)nr_bytes_written, (int)nr_bytes)); |
| 341 | return nr_bytes_written; |
| 342 | } |
| 343 | |
| 344 | |
| 345 | /* instances of the hw_disk device */ |
| 346 | |
| 347 | static void |
| 348 | hw_disk_instance_delete(device_instance *instance) |
| 349 | { |
| 350 | hw_disk_instance *data = device_instance_data(instance); |
| 351 | DITRACE(disk, ("delete - instance=%ld\n", |
| 352 | (unsigned long)device_instance_to_external(instance))); |
| 353 | free(data); |
| 354 | } |
| 355 | |
| 356 | static int |
| 357 | hw_disk_instance_read(device_instance *instance, |
| 358 | void *buf, |
| 359 | unsigned_word len) |
| 360 | { |
| 361 | hw_disk_instance *data = device_instance_data(instance); |
| 362 | DITRACE(disk, ("read - instance=%ld len=%ld\n", |
| 363 | (unsigned long)device_instance_to_external(instance), |
| 364 | (long)len)); |
| 365 | if ((data->pos + len) < data->pos) |
| 366 | return -1; /* overflow */ |
| 367 | if (fseek(data->disk->image, data->pos, SEEK_SET) < 0) |
| 368 | return -1; |
| 369 | if (fread(buf, len, 1, data->disk->image) != 1) |
| 370 | return -1; |
| 371 | data->pos = ftell(data->disk->image); |
| 372 | return len; |
| 373 | } |
| 374 | |
| 375 | static int |
| 376 | hw_disk_instance_write(device_instance *instance, |
| 377 | const void *buf, |
| 378 | unsigned_word len) |
| 379 | { |
| 380 | hw_disk_instance *data = device_instance_data(instance); |
| 381 | DITRACE(disk, ("write - instance=%ld len=%ld\n", |
| 382 | (unsigned long)device_instance_to_external(instance), |
| 383 | (long)len)); |
| 384 | if ((data->pos + len) < data->pos) |
| 385 | return -1; /* overflow */ |
| 386 | if (data->disk->read_only) |
| 387 | return -1; |
| 388 | if (fseek(data->disk->image, data->pos, SEEK_SET) < 0) |
| 389 | return -1; |
| 390 | if (fwrite(buf, len, 1, data->disk->image) != 1) |
| 391 | return -1; |
| 392 | data->pos = ftell(data->disk->image); |
| 393 | return len; |
| 394 | } |
| 395 | |
| 396 | static int |
| 397 | hw_disk_instance_seek(device_instance *instance, |
| 398 | unsigned_word pos_hi, |
| 399 | unsigned_word pos_lo) |
| 400 | { |
| 401 | hw_disk_instance *data = device_instance_data(instance); |
| 402 | if (pos_hi != 0) |
| 403 | device_error(device_instance_device(instance), |
| 404 | "seek - extended addressing unimplemented"); |
| 405 | DITRACE(disk, ("seek - instance=%ld pos_hi=%ld pos_lo=%ld\n", |
| 406 | (unsigned long)device_instance_to_external(instance), |
| 407 | (long)pos_hi, (long)pos_lo)); |
| 408 | data->pos = pos_lo; |
| 409 | return 0; |
| 410 | } |
| 411 | |
| 412 | static int |
| 413 | hw_disk_max_transfer(device_instance *instance, |
| 414 | int n_stack_args, |
| 415 | unsigned32 stack_args[/*n_stack_args*/], |
| 416 | int n_stack_returns, |
| 417 | unsigned32 stack_returns[/*n_stack_returns*/]) |
| 418 | { |
| 419 | device *me = device_instance_device(instance); |
| 420 | if ((n_stack_args != 0) |
| 421 | || (n_stack_returns != 1)) { |
| 422 | device_error(me, "Incorrect number of arguments for max-transfer method\n"); |
| 423 | return -1; |
| 424 | } |
| 425 | else { |
| 426 | unsigned_cell max_transfer; |
| 427 | if (device_find_property(me, "max-transfer")) |
| 428 | max_transfer = device_find_integer_property(me, "max-transfer"); |
| 429 | else |
| 430 | max_transfer = 512; |
| 431 | DITRACE(disk, ("max-transfer - instance=%ld max-transfer=%ld\n", |
| 432 | (unsigned long)device_instance_to_external(instance), |
| 433 | (long int)max_transfer)); |
| 434 | stack_returns[0] = max_transfer; |
| 435 | return 0; |
| 436 | } |
| 437 | } |
| 438 | |
| 439 | static int |
| 440 | hw_disk_block_size(device_instance *instance, |
| 441 | int n_stack_args, |
| 442 | unsigned32 stack_args[/*n_stack_args*/], |
| 443 | int n_stack_returns, |
| 444 | unsigned32 stack_returns[/*n_stack_returns*/]) |
| 445 | { |
| 446 | device *me = device_instance_device(instance); |
| 447 | if ((n_stack_args != 0) |
| 448 | || (n_stack_returns != 1)) { |
| 449 | device_error(me, "Incorrect number of arguments for block-size method\n"); |
| 450 | return -1; |
| 451 | } |
| 452 | else { |
| 453 | unsigned_cell block_size; |
| 454 | if (device_find_property(me, "block-size")) |
| 455 | block_size = device_find_integer_property(me, "block-size"); |
| 456 | else |
| 457 | block_size = 512; |
| 458 | DITRACE(disk, ("block-size - instance=%ld block-size=%ld\n", |
| 459 | (unsigned long)device_instance_to_external(instance), |
| 460 | (long int)block_size)); |
| 461 | stack_returns[0] = block_size; |
| 462 | return 0; |
| 463 | } |
| 464 | } |
| 465 | |
| 466 | static int |
| 467 | hw_disk_nr_blocks(device_instance *instance, |
| 468 | int n_stack_args, |
| 469 | unsigned32 stack_args[/*n_stack_args*/], |
| 470 | int n_stack_returns, |
| 471 | unsigned32 stack_returns[/*n_stack_returns*/]) |
| 472 | { |
| 473 | device *me = device_instance_device(instance); |
| 474 | if ((n_stack_args != 0) |
| 475 | || (n_stack_returns != 1)) { |
| 476 | device_error(me, "Incorrect number of arguments for block-size method\n"); |
| 477 | return -1; |
| 478 | } |
| 479 | else { |
| 480 | unsigned_word nr_blocks; |
| 481 | if (device_find_property(me, "#blocks")) |
| 482 | nr_blocks = device_find_integer_property(me, "#blocks"); |
| 483 | else |
| 484 | nr_blocks = -1; |
| 485 | DITRACE(disk, ("#blocks - instance=%ld #blocks=%ld\n", |
| 486 | (unsigned long)device_instance_to_external(instance), |
| 487 | (long int)nr_blocks)); |
| 488 | stack_returns[0] = nr_blocks; |
| 489 | return 0; |
| 490 | } |
| 491 | } |
| 492 | |
| 493 | static device_instance_methods hw_disk_instance_methods[] = { |
| 494 | { "max-transfer", hw_disk_max_transfer }, |
| 495 | { "block-size", hw_disk_block_size }, |
| 496 | { "#blocks", hw_disk_nr_blocks }, |
| 497 | { NULL, }, |
| 498 | }; |
| 499 | |
| 500 | static const device_instance_callbacks hw_disk_instance_callbacks = { |
| 501 | hw_disk_instance_delete, |
| 502 | hw_disk_instance_read, |
| 503 | hw_disk_instance_write, |
| 504 | hw_disk_instance_seek, |
| 505 | hw_disk_instance_methods, |
| 506 | }; |
| 507 | |
| 508 | static device_instance * |
| 509 | hw_disk_create_instance(device *me, |
| 510 | const char *path, |
| 511 | const char *args) |
| 512 | { |
| 513 | device_instance *instance; |
| 514 | hw_disk_device *disk = device_data(me); |
| 515 | hw_disk_instance *data = ZALLOC(hw_disk_instance); |
| 516 | data->disk = disk; |
| 517 | data->pos = 0; |
| 518 | instance = device_create_instance_from(me, NULL, |
| 519 | data, |
| 520 | path, args, |
| 521 | &hw_disk_instance_callbacks); |
| 522 | DITRACE(disk, ("create - path=%s(%s) instance=%ld\n", |
| 523 | path, args, |
| 524 | (unsigned long)device_instance_to_external(instance))); |
| 525 | return pk_disklabel_create_instance(instance, args); |
| 526 | } |
| 527 | |
| 528 | static device_callbacks const hw_disk_callbacks = { |
| 529 | { hw_disk_init_address, NULL }, |
| 530 | { NULL, }, /* address */ |
| 531 | { hw_disk_io_read_buffer, |
| 532 | hw_disk_io_write_buffer, }, |
| 533 | { NULL, }, /* DMA */ |
| 534 | { NULL, }, /* interrupt */ |
| 535 | { NULL, }, /* unit */ |
| 536 | hw_disk_create_instance, |
| 537 | hw_disk_ioctl, |
| 538 | }; |
| 539 | |
| 540 | |
| 541 | static void * |
| 542 | hw_disk_create(const char *name, |
| 543 | const device_unit *unit_address, |
| 544 | const char *args) |
| 545 | { |
| 546 | /* create the descriptor */ |
| 547 | hw_disk_device *hw_disk = ZALLOC(hw_disk_device); |
| 548 | return hw_disk; |
| 549 | } |
| 550 | |
| 551 | |
| 552 | const device_descriptor hw_disk_device_descriptor[] = { |
| 553 | { "disk", hw_disk_create, &hw_disk_callbacks }, |
| 554 | { "cdrom", hw_disk_create, &hw_disk_callbacks }, |
| 555 | { "floppy", hw_disk_create, &hw_disk_callbacks }, |
| 556 | { NULL }, |
| 557 | }; |
| 558 | |
| 559 | #endif /* _HW_DISK_C_ */ |