git.sur5r.net Git - u-boot/blob - lib/efi_loader/efi_device_path.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * EFI device path from u-boot device-model mapping
   4  *
   5  * (C) Copyright 2017 Rob Clark
   6  */
   7
   8 #define LOG_CATEGORY LOGL_ERR
   9
  10 #include <common.h>
  11 #include <blk.h>
  12 #include <dm.h>
  13 #include <usb.h>
  14 #include <mmc.h>
  15 #include <efi_loader.h>
  16 #include <inttypes.h>
  17 #include <part.h>
  18
  19 /* template END node: */
  20 static const struct efi_device_path END = {
  21         .type     = DEVICE_PATH_TYPE_END,
  22         .sub_type = DEVICE_PATH_SUB_TYPE_END,
  23         .length   = sizeof(END),
  24 };
  25
  26 #define U_BOOT_GUID \
  27         EFI_GUID(0xe61d73b9, 0xa384, 0x4acc, \
  28                  0xae, 0xab, 0x82, 0xe8, 0x28, 0xf3, 0x62, 0x8b)
  29
  30 /* template ROOT node: */
  31 static const struct efi_device_path_vendor ROOT = {
  32         .dp = {
  33                 .type     = DEVICE_PATH_TYPE_HARDWARE_DEVICE,
  34                 .sub_type = DEVICE_PATH_SUB_TYPE_VENDOR,
  35                 .length   = sizeof(ROOT),
  36         },
  37         .guid = U_BOOT_GUID,
  38 };
  39
  40 #if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
  41 /*
  42  * Determine if an MMC device is an SD card.
  43  *
  44  * @desc        block device descriptor
  45  * @return      true if the device is an SD card
  46  */
  47 static bool is_sd(struct blk_desc *desc)
  48 {
  49         struct mmc *mmc = find_mmc_device(desc->devnum);
  50
  51         if (!mmc)
  52                 return false;
  53
  54         return IS_SD(mmc) != 0U;
  55 }
  56 #endif
  57
  58 static void *dp_alloc(size_t sz)
  59 {
  60         void *buf;
  61
  62         if (efi_allocate_pool(EFI_ALLOCATE_ANY_PAGES, sz, &buf) !=
  63             EFI_SUCCESS) {
  64                 debug("EFI: ERROR: out of memory in %s\n", __func__);
  65                 return NULL;
  66         }
  67
  68         memset(buf, 0, sz);
  69         return buf;
  70 }
  71
  72 /*
  73  * Iterate to next block in device-path, terminating (returning NULL)
  74  * at /End* node.
  75  */
  76 struct efi_device_path *efi_dp_next(const struct efi_device_path *dp)
  77 {
  78         if (dp == NULL)
  79                 return NULL;
  80         if (dp->type == DEVICE_PATH_TYPE_END)
  81                 return NULL;
  82         dp = ((void *)dp) + dp->length;
  83         if (dp->type == DEVICE_PATH_TYPE_END)
  84                 return NULL;
  85         return (struct efi_device_path *)dp;
  86 }
  87
  88 /*
  89  * Compare two device-paths, stopping when the shorter of the two hits
  90  * an End* node.  This is useful to, for example, compare a device-path
  91  * representing a device with one representing a file on the device, or
  92  * a device with a parent device.
  93  */
  94 int efi_dp_match(const struct efi_device_path *a,
  95                  const struct efi_device_path *b)
  96 {
  97         while (1) {
  98                 int ret;
  99
 100                 ret = memcmp(&a->length, &b->length, sizeof(a->length));
 101                 if (ret)
 102                         return ret;
 103
 104                 ret = memcmp(a, b, a->length);
 105                 if (ret)
 106                         return ret;
 107
 108                 a = efi_dp_next(a);
 109                 b = efi_dp_next(b);
 110
 111                 if (!a || !b)
 112                         return 0;
 113         }
 114 }
 115
 116 /*
 117  * See UEFI spec (section 3.1.2, about short-form device-paths..
 118  * tl;dr: we can have a device-path that starts with a USB WWID
 119  * or USB Class node, and a few other cases which don't encode
 120  * the full device path with bus hierarchy:
 121  *
 122  *   - MESSAGING:USB_WWID
 123  *   - MESSAGING:USB_CLASS
 124  *   - MEDIA:FILE_PATH
 125  *   - MEDIA:HARD_DRIVE
 126  *   - MESSAGING:URI
 127  */
 128 static struct efi_device_path *shorten_path(struct efi_device_path *dp)
 129 {
 130         while (dp) {
 131                 /*
 132                  * TODO: Add MESSAGING:USB_WWID and MESSAGING:URI..
 133                  * in practice fallback.efi just uses MEDIA:HARD_DRIVE
 134                  * so not sure when we would see these other cases.
 135                  */
 136                 if (EFI_DP_TYPE(dp, MESSAGING_DEVICE, MSG_USB_CLASS) ||
 137                     EFI_DP_TYPE(dp, MEDIA_DEVICE, HARD_DRIVE_PATH) ||
 138                     EFI_DP_TYPE(dp, MEDIA_DEVICE, FILE_PATH))
 139                         return dp;
 140
 141                 dp = efi_dp_next(dp);
 142         }
 143
 144         return dp;
 145 }
 146
 147 static struct efi_object *find_obj(struct efi_device_path *dp, bool short_path,
 148                                    struct efi_device_path **rem)
 149 {
 150         struct efi_object *efiobj;
 151         efi_uintn_t dp_size = efi_dp_instance_size(dp);
 152
 153         list_for_each_entry(efiobj, &efi_obj_list, link) {
 154                 struct efi_handler *handler;
 155                 struct efi_device_path *obj_dp;
 156                 efi_status_t ret;
 157
 158                 ret = efi_search_protocol(efiobj->handle,
 159                                           &efi_guid_device_path, &handler);
 160                 if (ret != EFI_SUCCESS)
 161                         continue;
 162                 obj_dp = handler->protocol_interface;
 163
 164                 do {
 165                         if (efi_dp_match(dp, obj_dp) == 0) {
 166                                 if (rem) {
 167                                         /*
 168                                          * Allow partial matches, but inform
 169                                          * the caller.
 170                                          */
 171                                         *rem = ((void *)dp) +
 172                                                 efi_dp_instance_size(obj_dp);
 173                                         return efiobj;
 174                                 } else {
 175                                         /* Only return on exact matches */
 176                                         if (efi_dp_instance_size(obj_dp) ==
 177                                             dp_size)
 178                                                 return efiobj;
 179                                 }
 180                         }
 181
 182                         obj_dp = shorten_path(efi_dp_next(obj_dp));
 183                 } while (short_path && obj_dp);
 184         }
 185
 186         return NULL;
 187 }
 188
 189 /*
 190  * Find an efiobj from device-path, if 'rem' is not NULL, returns the
 191  * remaining part of the device path after the matched object.
 192  */
 193 struct efi_object *efi_dp_find_obj(struct efi_device_path *dp,
 194                                    struct efi_device_path **rem)
 195 {
 196         struct efi_object *efiobj;
 197
 198         /* Search for an exact match first */
 199         efiobj = find_obj(dp, false, NULL);
 200
 201         /* Then for a fuzzy match */
 202         if (!efiobj)
 203                 efiobj = find_obj(dp, false, rem);
 204
 205         /* And now for a fuzzy short match */
 206         if (!efiobj)
 207                 efiobj = find_obj(dp, true, rem);
 208
 209         return efiobj;
 210 }
 211
 212 /*
 213  * Determine the last device path node that is not the end node.
 214  *
 215  * @dp          device path
 216  * @return      last node before the end node if it exists
 217  *              otherwise NULL
 218  */
 219 const struct efi_device_path *efi_dp_last_node(const struct efi_device_path *dp)
 220 {
 221         struct efi_device_path *ret;
 222
 223         if (!dp || dp->type == DEVICE_PATH_TYPE_END)
 224                 return NULL;
 225         while (dp) {
 226                 ret = (struct efi_device_path *)dp;
 227                 dp = efi_dp_next(dp);
 228         }
 229         return ret;
 230 }
 231
 232 /* get size of the first device path instance excluding end node */
 233 efi_uintn_t efi_dp_instance_size(const struct efi_device_path *dp)
 234 {
 235         efi_uintn_t sz = 0;
 236
 237         if (!dp || dp->type == DEVICE_PATH_TYPE_END)
 238                 return 0;
 239         while (dp) {
 240                 sz += dp->length;
 241                 dp = efi_dp_next(dp);
 242         }
 243
 244         return sz;
 245 }
 246
 247 /* get size of multi-instance device path excluding end node */
 248 efi_uintn_t efi_dp_size(const struct efi_device_path *dp)
 249 {
 250         const struct efi_device_path *p = dp;
 251
 252         if (!p)
 253                 return 0;
 254         while (p->type != DEVICE_PATH_TYPE_END ||
 255                p->sub_type != DEVICE_PATH_SUB_TYPE_END)
 256                 p = (void *)p + p->length;
 257
 258         return (void *)p - (void *)dp;
 259 }
 260
 261 /* copy multi-instance device path */
 262 struct efi_device_path *efi_dp_dup(const struct efi_device_path *dp)
 263 {
 264         struct efi_device_path *ndp;
 265         size_t sz = efi_dp_size(dp) + sizeof(END);
 266
 267         if (!dp)
 268                 return NULL;
 269
 270         ndp = dp_alloc(sz);
 271         if (!ndp)
 272                 return NULL;
 273         memcpy(ndp, dp, sz);
 274
 275         return ndp;
 276 }
 277
 278 struct efi_device_path *efi_dp_append(const struct efi_device_path *dp1,
 279                                       const struct efi_device_path *dp2)
 280 {
 281         struct efi_device_path *ret;
 282
 283         if (!dp1 && !dp2) {
 284                 /* return an end node */
 285                 ret = efi_dp_dup(&END);
 286         } else if (!dp1) {
 287                 ret = efi_dp_dup(dp2);
 288         } else if (!dp2) {
 289                 ret = efi_dp_dup(dp1);
 290         } else {
 291                 /* both dp1 and dp2 are non-null */
 292                 unsigned sz1 = efi_dp_size(dp1);
 293                 unsigned sz2 = efi_dp_size(dp2);
 294                 void *p = dp_alloc(sz1 + sz2 + sizeof(END));
 295                 if (!p)
 296                         return NULL;
 297                 memcpy(p, dp1, sz1);
 298                 /* the end node of the second device path has to be retained */
 299                 memcpy(p + sz1, dp2, sz2 + sizeof(END));
 300                 ret = p;
 301         }
 302
 303         return ret;
 304 }
 305
 306 struct efi_device_path *efi_dp_append_node(const struct efi_device_path *dp,
 307                                            const struct efi_device_path *node)
 308 {
 309         struct efi_device_path *ret;
 310
 311         if (!node && !dp) {
 312                 ret = efi_dp_dup(&END);
 313         } else if (!node) {
 314                 ret = efi_dp_dup(dp);
 315         } else if (!dp) {
 316                 size_t sz = node->length;
 317                 void *p = dp_alloc(sz + sizeof(END));
 318                 if (!p)
 319                         return NULL;
 320                 memcpy(p, node, sz);
 321                 memcpy(p + sz, &END, sizeof(END));
 322                 ret = p;
 323         } else {
 324                 /* both dp and node are non-null */
 325                 size_t sz = efi_dp_size(dp);
 326                 void *p = dp_alloc(sz + node->length + sizeof(END));
 327                 if (!p)
 328                         return NULL;
 329                 memcpy(p, dp, sz);
 330                 memcpy(p + sz, node, node->length);
 331                 memcpy(p + sz + node->length, &END, sizeof(END));
 332                 ret = p;
 333         }
 334
 335         return ret;
 336 }
 337
 338 struct efi_device_path *efi_dp_create_device_node(const u8 type,
 339                                                   const u8 sub_type,
 340                                                   const u16 length)
 341 {
 342         struct efi_device_path *ret;
 343
 344         ret = dp_alloc(length);
 345         if (!ret)
 346                 return ret;
 347         ret->type = type;
 348         ret->sub_type = sub_type;
 349         ret->length = length;
 350         return ret;
 351 }
 352
 353 struct efi_device_path *efi_dp_append_instance(
 354                 const struct efi_device_path *dp,
 355                 const struct efi_device_path *dpi)
 356 {
 357         size_t sz, szi;
 358         struct efi_device_path *p, *ret;
 359
 360         if (!dpi)
 361                 return NULL;
 362         if (!dp)
 363                 return efi_dp_dup(dpi);
 364         sz = efi_dp_size(dp);
 365         szi = efi_dp_instance_size(dpi);
 366         p = dp_alloc(sz + szi + 2 * sizeof(END));
 367         if (!p)
 368                 return NULL;
 369         ret = p;
 370         memcpy(p, dp, sz + sizeof(END));
 371         p = (void *)p + sz;
 372         p->sub_type = DEVICE_PATH_SUB_TYPE_INSTANCE_END;
 373         p = (void *)p + sizeof(END);
 374         memcpy(p, dpi, szi);
 375         p = (void *)p + szi;
 376         memcpy(p, &END, sizeof(END));
 377         return ret;
 378 }
 379
 380 struct efi_device_path *efi_dp_get_next_instance(struct efi_device_path **dp,
 381                                                  efi_uintn_t *size)
 382 {
 383         size_t sz;
 384         struct efi_device_path *p;
 385
 386         if (size)
 387                 *size = 0;
 388         if (!dp || !*dp)
 389                 return NULL;
 390         p = *dp;
 391         sz = efi_dp_instance_size(*dp);
 392         p = dp_alloc(sz + sizeof(END));
 393         if (!p)
 394                 return NULL;
 395         memcpy(p, *dp, sz + sizeof(END));
 396         *dp = (void *)*dp + sz;
 397         if ((*dp)->sub_type == DEVICE_PATH_SUB_TYPE_INSTANCE_END)
 398                 *dp = (void *)*dp + sizeof(END);
 399         else
 400                 *dp = NULL;
 401         if (size)
 402                 *size = sz + sizeof(END);
 403         return p;
 404 }
 405
 406 bool efi_dp_is_multi_instance(const struct efi_device_path *dp)
 407 {
 408         const struct efi_device_path *p = dp;
 409
 410         if (!p)
 411                 return false;
 412         while (p->type != DEVICE_PATH_TYPE_END)
 413                 p = (void *)p + p->length;
 414         return p->sub_type == DEVICE_PATH_SUB_TYPE_INSTANCE_END;
 415 }
 416
 417 #ifdef CONFIG_DM
 418 /* size of device-path not including END node for device and all parents
 419  * up to the root device.
 420  */
 421 static unsigned dp_size(struct udevice *dev)
 422 {
 423         if (!dev || !dev->driver)
 424                 return sizeof(ROOT);
 425
 426         switch (dev->driver->id) {
 427         case UCLASS_ROOT:
 428         case UCLASS_SIMPLE_BUS:
 429                 /* stop traversing parents at this point: */
 430                 return sizeof(ROOT);
 431         case UCLASS_ETH:
 432                 return dp_size(dev->parent) +
 433                         sizeof(struct efi_device_path_mac_addr);
 434 #ifdef CONFIG_BLK
 435         case UCLASS_BLK:
 436                 switch (dev->parent->uclass->uc_drv->id) {
 437 #ifdef CONFIG_IDE
 438                 case UCLASS_IDE:
 439                         return dp_size(dev->parent) +
 440                                 sizeof(struct efi_device_path_atapi);
 441 #endif
 442 #if defined(CONFIG_SCSI) && defined(CONFIG_DM_SCSI)
 443                 case UCLASS_SCSI:
 444                         return dp_size(dev->parent) +
 445                                 sizeof(struct efi_device_path_scsi);
 446 #endif
 447 #if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
 448                 case UCLASS_MMC:
 449                         return dp_size(dev->parent) +
 450                                 sizeof(struct efi_device_path_sd_mmc_path);
 451 #endif
 452                 default:
 453                         return dp_size(dev->parent);
 454                 }
 455 #endif
 456 #if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
 457         case UCLASS_MMC:
 458                 return dp_size(dev->parent) +
 459                         sizeof(struct efi_device_path_sd_mmc_path);
 460 #endif
 461         case UCLASS_MASS_STORAGE:
 462         case UCLASS_USB_HUB:
 463                 return dp_size(dev->parent) +
 464                         sizeof(struct efi_device_path_usb_class);
 465         default:
 466                 /* just skip over unknown classes: */
 467                 return dp_size(dev->parent);
 468         }
 469 }
 470
 471 /*
 472  * Recursively build a device path.
 473  *
 474  * @buf         pointer to the end of the device path
 475  * @dev         device
 476  * @return      pointer to the end of the device path
 477  */
 478 static void *dp_fill(void *buf, struct udevice *dev)
 479 {
 480         if (!dev || !dev->driver)
 481                 return buf;
 482
 483         switch (dev->driver->id) {
 484         case UCLASS_ROOT:
 485         case UCLASS_SIMPLE_BUS: {
 486                 /* stop traversing parents at this point: */
 487                 struct efi_device_path_vendor *vdp = buf;
 488                 *vdp = ROOT;
 489                 return &vdp[1];
 490         }
 491 #ifdef CONFIG_DM_ETH
 492         case UCLASS_ETH: {
 493                 struct efi_device_path_mac_addr *dp =
 494                         dp_fill(buf, dev->parent);
 495                 struct eth_pdata *pdata = dev->platdata;
 496
 497                 dp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
 498                 dp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_MAC_ADDR;
 499                 dp->dp.length = sizeof(*dp);
 500                 memset(&dp->mac, 0, sizeof(dp->mac));
 501                 /* We only support IPv4 */
 502                 memcpy(&dp->mac, &pdata->enetaddr, ARP_HLEN);
 503                 /* Ethernet */
 504                 dp->if_type = 1;
 505                 return &dp[1];
 506         }
 507 #endif
 508 #ifdef CONFIG_BLK
 509         case UCLASS_BLK:
 510                 switch (dev->parent->uclass->uc_drv->id) {
 511 #ifdef CONFIG_IDE
 512                 case UCLASS_IDE: {
 513                         struct efi_device_path_atapi *dp =
 514                         dp_fill(buf, dev->parent);
 515                         struct blk_desc *desc = dev_get_uclass_platdata(dev);
 516
 517                         dp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
 518                         dp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_ATAPI;
 519                         dp->dp.length = sizeof(*dp);
 520                         dp->logical_unit_number = desc->devnum;
 521                         dp->primary_secondary = IDE_BUS(desc->devnum);
 522                         dp->slave_master = desc->devnum %
 523                                 (CONFIG_SYS_IDE_MAXDEVICE /
 524                                  CONFIG_SYS_IDE_MAXBUS);
 525                         return &dp[1];
 526                         }
 527 #endif
 528 #if defined(CONFIG_SCSI) && defined(CONFIG_DM_SCSI)
 529                 case UCLASS_SCSI: {
 530                         struct efi_device_path_scsi *dp =
 531                                 dp_fill(buf, dev->parent);
 532                         struct blk_desc *desc = dev_get_uclass_platdata(dev);
 533
 534                         dp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
 535                         dp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_SCSI;
 536                         dp->dp.length = sizeof(*dp);
 537                         dp->logical_unit_number = desc->lun;
 538                         dp->target_id = desc->target;
 539                         return &dp[1];
 540                         }
 541 #endif
 542 #if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
 543                 case UCLASS_MMC: {
 544                         struct efi_device_path_sd_mmc_path *sddp =
 545                                 dp_fill(buf, dev->parent);
 546                         struct blk_desc *desc = dev_get_uclass_platdata(dev);
 547
 548                         sddp->dp.type     = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
 549                         sddp->dp.sub_type = is_sd(desc) ?
 550                                 DEVICE_PATH_SUB_TYPE_MSG_SD :
 551                                 DEVICE_PATH_SUB_TYPE_MSG_MMC;
 552                         sddp->dp.length   = sizeof(*sddp);
 553                         sddp->slot_number = dev->seq;
 554                         return &sddp[1];
 555                         }
 556 #endif
 557                 default:
 558                         debug("%s(%u) %s: unhandled parent class: %s (%u)\n",
 559                               __FILE__, __LINE__, __func__,
 560                               dev->name, dev->parent->uclass->uc_drv->id);
 561                         return dp_fill(buf, dev->parent);
 562                 }
 563 #endif
 564 #if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
 565         case UCLASS_MMC: {
 566                 struct efi_device_path_sd_mmc_path *sddp =
 567                         dp_fill(buf, dev->parent);
 568                 struct mmc *mmc = mmc_get_mmc_dev(dev);
 569                 struct blk_desc *desc = mmc_get_blk_desc(mmc);
 570
 571                 sddp->dp.type     = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
 572                 sddp->dp.sub_type = is_sd(desc) ?
 573                         DEVICE_PATH_SUB_TYPE_MSG_SD :
 574                         DEVICE_PATH_SUB_TYPE_MSG_MMC;
 575                 sddp->dp.length   = sizeof(*sddp);
 576                 sddp->slot_number = dev->seq;
 577
 578                 return &sddp[1];
 579         }
 580 #endif
 581         case UCLASS_MASS_STORAGE:
 582         case UCLASS_USB_HUB: {
 583                 struct efi_device_path_usb_class *udp =
 584                         dp_fill(buf, dev->parent);
 585                 struct usb_device *udev = dev_get_parent_priv(dev);
 586                 struct usb_device_descriptor *desc = &udev->descriptor;
 587
 588                 udp->dp.type     = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
 589                 udp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_USB_CLASS;
 590                 udp->dp.length   = sizeof(*udp);
 591                 udp->vendor_id   = desc->idVendor;
 592                 udp->product_id  = desc->idProduct;
 593                 udp->device_class    = desc->bDeviceClass;
 594                 udp->device_subclass = desc->bDeviceSubClass;
 595                 udp->device_protocol = desc->bDeviceProtocol;
 596
 597                 return &udp[1];
 598         }
 599         default:
 600                 debug("%s(%u) %s: unhandled device class: %s (%u)\n",
 601                       __FILE__, __LINE__, __func__,
 602                       dev->name, dev->driver->id);
 603                 return dp_fill(buf, dev->parent);
 604         }
 605 }
 606
 607 /* Construct a device-path from a device: */
 608 struct efi_device_path *efi_dp_from_dev(struct udevice *dev)
 609 {
 610         void *buf, *start;
 611
 612         start = buf = dp_alloc(dp_size(dev) + sizeof(END));
 613         if (!buf)
 614                 return NULL;
 615         buf = dp_fill(buf, dev);
 616         *((struct efi_device_path *)buf) = END;
 617
 618         return start;
 619 }
 620 #endif
 621
 622 static unsigned dp_part_size(struct blk_desc *desc, int part)
 623 {
 624         unsigned dpsize;
 625
 626 #ifdef CONFIG_BLK
 627         {
 628                 struct udevice *dev;
 629                 int ret = blk_find_device(desc->if_type, desc->devnum, &dev);
 630
 631                 if (ret)
 632                         dev = desc->bdev->parent;
 633                 dpsize = dp_size(dev);
 634         }
 635 #else
 636         dpsize = sizeof(ROOT) + sizeof(struct efi_device_path_usb);
 637 #endif
 638
 639         if (part == 0) /* the actual disk, not a partition */
 640                 return dpsize;
 641
 642         if (desc->part_type == PART_TYPE_ISO)
 643                 dpsize += sizeof(struct efi_device_path_cdrom_path);
 644         else
 645                 dpsize += sizeof(struct efi_device_path_hard_drive_path);
 646
 647         return dpsize;
 648 }
 649
 650 /*
 651  * Create a device node for a block device partition.
 652  *
 653  * @buf         buffer to which the device path is wirtten
 654  * @desc        block device descriptor
 655  * @part        partition number, 0 identifies a block device
 656  */
 657 static void *dp_part_node(void *buf, struct blk_desc *desc, int part)
 658 {
 659         disk_partition_t info;
 660
 661         part_get_info(desc, part, &info);
 662
 663         if (desc->part_type == PART_TYPE_ISO) {
 664                 struct efi_device_path_cdrom_path *cddp = buf;
 665
 666                 cddp->boot_entry = part;
 667                 cddp->dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
 668                 cddp->dp.sub_type = DEVICE_PATH_SUB_TYPE_CDROM_PATH;
 669                 cddp->dp.length = sizeof(*cddp);
 670                 cddp->partition_start = info.start;
 671                 cddp->partition_end = info.size;
 672
 673                 buf = &cddp[1];
 674         } else {
 675                 struct efi_device_path_hard_drive_path *hddp = buf;
 676
 677                 hddp->dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
 678                 hddp->dp.sub_type = DEVICE_PATH_SUB_TYPE_HARD_DRIVE_PATH;
 679                 hddp->dp.length = sizeof(*hddp);
 680                 hddp->partition_number = part;
 681                 hddp->partition_start = info.start;
 682                 hddp->partition_end = info.size;
 683                 if (desc->part_type == PART_TYPE_EFI)
 684                         hddp->partmap_type = 2;
 685                 else
 686                         hddp->partmap_type = 1;
 687
 688                 switch (desc->sig_type) {
 689                 case SIG_TYPE_NONE:
 690                 default:
 691                         hddp->signature_type = 0;
 692                         memset(hddp->partition_signature, 0,
 693                                sizeof(hddp->partition_signature));
 694                         break;
 695                 case SIG_TYPE_MBR:
 696                         hddp->signature_type = 1;
 697                         memset(hddp->partition_signature, 0,
 698                                sizeof(hddp->partition_signature));
 699                         memcpy(hddp->partition_signature, &desc->mbr_sig,
 700                                sizeof(desc->mbr_sig));
 701                         break;
 702                 case SIG_TYPE_GUID:
 703                         hddp->signature_type = 2;
 704                         memcpy(hddp->partition_signature, &desc->guid_sig,
 705                                sizeof(hddp->partition_signature));
 706                         break;
 707                 }
 708
 709                 buf = &hddp[1];
 710         }
 711
 712         return buf;
 713 }
 714
 715 /*
 716  * Create a device path for a block device or one of its partitions.
 717  *
 718  * @buf         buffer to which the device path is wirtten
 719  * @desc        block device descriptor
 720  * @part        partition number, 0 identifies a block device
 721  */
 722 static void *dp_part_fill(void *buf, struct blk_desc *desc, int part)
 723 {
 724 #ifdef CONFIG_BLK
 725         {
 726                 struct udevice *dev;
 727                 int ret = blk_find_device(desc->if_type, desc->devnum, &dev);
 728
 729                 if (ret)
 730                         dev = desc->bdev->parent;
 731                 buf = dp_fill(buf, dev);
 732         }
 733 #else
 734         /*
 735          * We *could* make a more accurate path, by looking at if_type
 736          * and handling all the different cases like we do for non-
 737          * legacy (ie CONFIG_BLK=y) case.  But most important thing
 738          * is just to have a unique device-path for if_type+devnum.
 739          * So map things to a fictitious USB device.
 740          */
 741         struct efi_device_path_usb *udp;
 742
 743         memcpy(buf, &ROOT, sizeof(ROOT));
 744         buf += sizeof(ROOT);
 745
 746         udp = buf;
 747         udp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
 748         udp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_USB;
 749         udp->dp.length = sizeof(*udp);
 750         udp->parent_port_number = desc->if_type;
 751         udp->usb_interface = desc->devnum;
 752         buf = &udp[1];
 753 #endif
 754
 755         if (part == 0) /* the actual disk, not a partition */
 756                 return buf;
 757
 758         return dp_part_node(buf, desc, part);
 759 }
 760
 761 /* Construct a device-path from a partition on a blk device: */
 762 struct efi_device_path *efi_dp_from_part(struct blk_desc *desc, int part)
 763 {
 764         void *buf, *start;
 765
 766         start = buf = dp_alloc(dp_part_size(desc, part) + sizeof(END));
 767         if (!buf)
 768                 return NULL;
 769
 770         buf = dp_part_fill(buf, desc, part);
 771
 772         *((struct efi_device_path *)buf) = END;
 773
 774         return start;
 775 }
 776
 777 /*
 778  * Create a device node for a block device partition.
 779  *
 780  * @buf         buffer to which the device path is wirtten
 781  * @desc        block device descriptor
 782  * @part        partition number, 0 identifies a block device
 783  */
 784 struct efi_device_path *efi_dp_part_node(struct blk_desc *desc, int part)
 785 {
 786         efi_uintn_t dpsize;
 787         void *buf;
 788
 789         if (desc->part_type == PART_TYPE_ISO)
 790                 dpsize = sizeof(struct efi_device_path_cdrom_path);
 791         else
 792                 dpsize = sizeof(struct efi_device_path_hard_drive_path);
 793         buf = dp_alloc(dpsize);
 794
 795         dp_part_node(buf, desc, part);
 796
 797         return buf;
 798 }
 799
 800 /* convert path to an UEFI style path (ie. DOS style backslashes and utf16) */
 801 static void path_to_uefi(u16 *uefi, const char *path)
 802 {
 803         while (*path) {
 804                 char c = *(path++);
 805                 if (c == '/')
 806                         c = '\\';
 807                 *(uefi++) = c;
 808         }
 809         *uefi = '\0';
 810 }
 811
 812 /*
 813  * If desc is NULL, this creates a path with only the file component,
 814  * otherwise it creates a full path with both device and file components
 815  */
 816 struct efi_device_path *efi_dp_from_file(struct blk_desc *desc, int part,
 817                 const char *path)
 818 {
 819         struct efi_device_path_file_path *fp;
 820         void *buf, *start;
 821         unsigned dpsize = 0, fpsize;
 822
 823         if (desc)
 824                 dpsize = dp_part_size(desc, part);
 825
 826         fpsize = sizeof(struct efi_device_path) + 2 * (strlen(path) + 1);
 827         dpsize += fpsize;
 828
 829         start = buf = dp_alloc(dpsize + sizeof(END));
 830         if (!buf)
 831                 return NULL;
 832
 833         if (desc)
 834                 buf = dp_part_fill(buf, desc, part);
 835
 836         /* add file-path: */
 837         fp = buf;
 838         fp->dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
 839         fp->dp.sub_type = DEVICE_PATH_SUB_TYPE_FILE_PATH;
 840         fp->dp.length = fpsize;
 841         path_to_uefi(fp->str, path);
 842         buf += fpsize;
 843
 844         *((struct efi_device_path *)buf) = END;
 845
 846         return start;
 847 }
 848
 849 #ifdef CONFIG_NET
 850 struct efi_device_path *efi_dp_from_eth(void)
 851 {
 852 #ifndef CONFIG_DM_ETH
 853         struct efi_device_path_mac_addr *ndp;
 854 #endif
 855         void *buf, *start;
 856         unsigned dpsize = 0;
 857
 858         assert(eth_get_dev());
 859
 860 #ifdef CONFIG_DM_ETH
 861         dpsize += dp_size(eth_get_dev());
 862 #else
 863         dpsize += sizeof(ROOT);
 864         dpsize += sizeof(*ndp);
 865 #endif
 866
 867         start = buf = dp_alloc(dpsize + sizeof(END));
 868         if (!buf)
 869                 return NULL;
 870
 871 #ifdef CONFIG_DM_ETH
 872         buf = dp_fill(buf, eth_get_dev());
 873 #else
 874         memcpy(buf, &ROOT, sizeof(ROOT));
 875         buf += sizeof(ROOT);
 876
 877         ndp = buf;
 878         ndp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
 879         ndp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_MAC_ADDR;
 880         ndp->dp.length = sizeof(*ndp);
 881         ndp->if_type = 1; /* Ethernet */
 882         memcpy(ndp->mac.addr, eth_get_ethaddr(), ARP_HLEN);
 883         buf = &ndp[1];
 884 #endif
 885
 886         *((struct efi_device_path *)buf) = END;
 887
 888         return start;
 889 }
 890 #endif
 891
 892 /* Construct a device-path for memory-mapped image */
 893 struct efi_device_path *efi_dp_from_mem(uint32_t memory_type,
 894                                         uint64_t start_address,
 895                                         uint64_t end_address)
 896 {
 897         struct efi_device_path_memory *mdp;
 898         void *buf, *start;
 899
 900         start = buf = dp_alloc(sizeof(*mdp) + sizeof(END));
 901         if (!buf)
 902                 return NULL;
 903
 904         mdp = buf;
 905         mdp->dp.type = DEVICE_PATH_TYPE_HARDWARE_DEVICE;
 906         mdp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MEMORY;
 907         mdp->dp.length = sizeof(*mdp);
 908         mdp->memory_type = memory_type;
 909         mdp->start_address = start_address;
 910         mdp->end_address = end_address;
 911         buf = &mdp[1];
 912
 913         *((struct efi_device_path *)buf) = END;
 914
 915         return start;
 916 }
 917
 918 /*
 919  * Helper to split a full device path (containing both device and file
 920  * parts) into it's constituent parts.
 921  */
 922 efi_status_t efi_dp_split_file_path(struct efi_device_path *full_path,
 923                                     struct efi_device_path **device_path,
 924                                     struct efi_device_path **file_path)
 925 {
 926         struct efi_device_path *p, *dp, *fp;
 927
 928         *device_path = NULL;
 929         *file_path = NULL;
 930         dp = efi_dp_dup(full_path);
 931         if (!dp)
 932                 return EFI_OUT_OF_RESOURCES;
 933         p = dp;
 934         while (!EFI_DP_TYPE(p, MEDIA_DEVICE, FILE_PATH)) {
 935                 p = efi_dp_next(p);
 936                 if (!p)
 937                         return EFI_OUT_OF_RESOURCES;
 938         }
 939         fp = efi_dp_dup(p);
 940         if (!fp)
 941                 return EFI_OUT_OF_RESOURCES;
 942         p->type = DEVICE_PATH_TYPE_END;
 943         p->sub_type = DEVICE_PATH_SUB_TYPE_END;
 944         p->length = sizeof(*p);
 945
 946         *device_path = dp;
 947         *file_path = fp;
 948         return EFI_SUCCESS;
 949 }