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 #include <common.h>
   9 #include <blk.h>
  10 #include <dm.h>
  11 #include <usb.h>
  12 #include <mmc.h>
  13 #include <efi_loader.h>
  14 #include <part.h>
  15
  16 /* template END node: */
  17 static const struct efi_device_path END = {
  18         .type     = DEVICE_PATH_TYPE_END,
  19         .sub_type = DEVICE_PATH_SUB_TYPE_END,
  20         .length   = sizeof(END),
  21 };
  22
  23 /* template ROOT node: */
  24 static const struct efi_device_path_vendor ROOT = {
  25         .dp = {
  26                 .type     = DEVICE_PATH_TYPE_HARDWARE_DEVICE,
  27                 .sub_type = DEVICE_PATH_SUB_TYPE_VENDOR,
  28                 .length   = sizeof(ROOT),
  29         },
  30         .guid = U_BOOT_GUID,
  31 };
  32
  33 #if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
  34 /*
  35  * Determine if an MMC device is an SD card.
  36  *
  37  * @desc        block device descriptor
  38  * @return      true if the device is an SD card
  39  */
  40 static bool is_sd(struct blk_desc *desc)
  41 {
  42         struct mmc *mmc = find_mmc_device(desc->devnum);
  43
  44         if (!mmc)
  45                 return false;
  46
  47         return IS_SD(mmc) != 0U;
  48 }
  49 #endif
  50
  51 static void *dp_alloc(size_t sz)
  52 {
  53         void *buf;
  54
  55         if (efi_allocate_pool(EFI_ALLOCATE_ANY_PAGES, sz, &buf) !=
  56             EFI_SUCCESS) {
  57                 debug("EFI: ERROR: out of memory in %s\n", __func__);
  58                 return NULL;
  59         }
  60
  61         memset(buf, 0, sz);
  62         return buf;
  63 }
  64
  65 /*
  66  * Iterate to next block in device-path, terminating (returning NULL)
  67  * at /End* node.
  68  */
  69 struct efi_device_path *efi_dp_next(const struct efi_device_path *dp)
  70 {
  71         if (dp == NULL)
  72                 return NULL;
  73         if (dp->type == DEVICE_PATH_TYPE_END)
  74                 return NULL;
  75         dp = ((void *)dp) + dp->length;
  76         if (dp->type == DEVICE_PATH_TYPE_END)
  77                 return NULL;
  78         return (struct efi_device_path *)dp;
  79 }
  80
  81 /*
  82  * Compare two device-paths, stopping when the shorter of the two hits
  83  * an End* node. This is useful to, for example, compare a device-path
  84  * representing a device with one representing a file on the device, or
  85  * a device with a parent device.
  86  */
  87 int efi_dp_match(const struct efi_device_path *a,
  88                  const struct efi_device_path *b)
  89 {
  90         while (1) {
  91                 int ret;
  92
  93                 ret = memcmp(&a->length, &b->length, sizeof(a->length));
  94                 if (ret)
  95                         return ret;
  96
  97                 ret = memcmp(a, b, a->length);
  98                 if (ret)
  99                         return ret;
 100
 101                 a = efi_dp_next(a);
 102                 b = efi_dp_next(b);
 103
 104                 if (!a || !b)
 105                         return 0;
 106         }
 107 }
 108
 109 /*
 110  * We can have device paths that start with a USB WWID or a USB Class node,
 111  * and a few other cases which don't encode the full device path with bus
 112  * hierarchy:
 113  *
 114  *   - MESSAGING:USB_WWID
 115  *   - MESSAGING:USB_CLASS
 116  *   - MEDIA:FILE_PATH
 117  *   - MEDIA:HARD_DRIVE
 118  *   - MESSAGING:URI
 119  *
 120  * See UEFI spec (section 3.1.2, about short-form device-paths)
 121  */
 122 static struct efi_device_path *shorten_path(struct efi_device_path *dp)
 123 {
 124         while (dp) {
 125                 /*
 126                  * TODO: Add MESSAGING:USB_WWID and MESSAGING:URI..
 127                  * in practice fallback.efi just uses MEDIA:HARD_DRIVE
 128                  * so not sure when we would see these other cases.
 129                  */
 130                 if (EFI_DP_TYPE(dp, MESSAGING_DEVICE, MSG_USB_CLASS) ||
 131                     EFI_DP_TYPE(dp, MEDIA_DEVICE, HARD_DRIVE_PATH) ||
 132                     EFI_DP_TYPE(dp, MEDIA_DEVICE, FILE_PATH))
 133                         return dp;
 134
 135                 dp = efi_dp_next(dp);
 136         }
 137
 138         return dp;
 139 }
 140
 141 static struct efi_object *find_obj(struct efi_device_path *dp, bool short_path,
 142                                    struct efi_device_path **rem)
 143 {
 144         struct efi_object *efiobj;
 145         efi_uintn_t dp_size = efi_dp_instance_size(dp);
 146
 147         list_for_each_entry(efiobj, &efi_obj_list, link) {
 148                 struct efi_handler *handler;
 149                 struct efi_device_path *obj_dp;
 150                 efi_status_t ret;
 151
 152                 ret = efi_search_protocol(efiobj,
 153                                           &efi_guid_device_path, &handler);
 154                 if (ret != EFI_SUCCESS)
 155                         continue;
 156                 obj_dp = handler->protocol_interface;
 157
 158                 do {
 159                         if (efi_dp_match(dp, obj_dp) == 0) {
 160                                 if (rem) {
 161                                         /*
 162                                          * Allow partial matches, but inform
 163                                          * the caller.
 164                                          */
 165                                         *rem = ((void *)dp) +
 166                                                 efi_dp_instance_size(obj_dp);
 167                                         return efiobj;
 168                                 } else {
 169                                         /* Only return on exact matches */
 170                                         if (efi_dp_instance_size(obj_dp) ==
 171                                             dp_size)
 172                                                 return efiobj;
 173                                 }
 174                         }
 175
 176                         obj_dp = shorten_path(efi_dp_next(obj_dp));
 177                 } while (short_path && obj_dp);
 178         }
 179
 180         return NULL;
 181 }
 182
 183 /*
 184  * Find an efiobj from device-path, if 'rem' is not NULL, returns the
 185  * remaining part of the device path after the matched object.
 186  */
 187 struct efi_object *efi_dp_find_obj(struct efi_device_path *dp,
 188                                    struct efi_device_path **rem)
 189 {
 190         struct efi_object *efiobj;
 191
 192         /* Search for an exact match first */
 193         efiobj = find_obj(dp, false, NULL);
 194
 195         /* Then for a fuzzy match */
 196         if (!efiobj)
 197                 efiobj = find_obj(dp, false, rem);
 198
 199         /* And now for a fuzzy short match */
 200         if (!efiobj)
 201                 efiobj = find_obj(dp, true, rem);
 202
 203         return efiobj;
 204 }
 205
 206 /*
 207  * Determine the last device path node that is not the end node.
 208  *
 209  * @dp          device path
 210  * @return      last node before the end node if it exists
 211  *              otherwise NULL
 212  */
 213 const struct efi_device_path *efi_dp_last_node(const struct efi_device_path *dp)
 214 {
 215         struct efi_device_path *ret;
 216
 217         if (!dp || dp->type == DEVICE_PATH_TYPE_END)
 218                 return NULL;
 219         while (dp) {
 220                 ret = (struct efi_device_path *)dp;
 221                 dp = efi_dp_next(dp);
 222         }
 223         return ret;
 224 }
 225
 226 /* get size of the first device path instance excluding end node */
 227 efi_uintn_t efi_dp_instance_size(const struct efi_device_path *dp)
 228 {
 229         efi_uintn_t sz = 0;
 230
 231         if (!dp || dp->type == DEVICE_PATH_TYPE_END)
 232                 return 0;
 233         while (dp) {
 234                 sz += dp->length;
 235                 dp = efi_dp_next(dp);
 236         }
 237
 238         return sz;
 239 }
 240
 241 /* get size of multi-instance device path excluding end node */
 242 efi_uintn_t efi_dp_size(const struct efi_device_path *dp)
 243 {
 244         const struct efi_device_path *p = dp;
 245
 246         if (!p)
 247                 return 0;
 248         while (p->type != DEVICE_PATH_TYPE_END ||
 249                p->sub_type != DEVICE_PATH_SUB_TYPE_END)
 250                 p = (void *)p + p->length;
 251
 252         return (void *)p - (void *)dp;
 253 }
 254
 255 /* copy multi-instance device path */
 256 struct efi_device_path *efi_dp_dup(const struct efi_device_path *dp)
 257 {
 258         struct efi_device_path *ndp;
 259         size_t sz = efi_dp_size(dp) + sizeof(END);
 260
 261         if (!dp)
 262                 return NULL;
 263
 264         ndp = dp_alloc(sz);
 265         if (!ndp)
 266                 return NULL;
 267         memcpy(ndp, dp, sz);
 268
 269         return ndp;
 270 }
 271
 272 struct efi_device_path *efi_dp_append(const struct efi_device_path *dp1,
 273                                       const struct efi_device_path *dp2)
 274 {
 275         struct efi_device_path *ret;
 276
 277         if (!dp1 && !dp2) {
 278                 /* return an end node */
 279                 ret = efi_dp_dup(&END);
 280         } else if (!dp1) {
 281                 ret = efi_dp_dup(dp2);
 282         } else if (!dp2) {
 283                 ret = efi_dp_dup(dp1);
 284         } else {
 285                 /* both dp1 and dp2 are non-null */
 286                 unsigned sz1 = efi_dp_size(dp1);
 287                 unsigned sz2 = efi_dp_size(dp2);
 288                 void *p = dp_alloc(sz1 + sz2 + sizeof(END));
 289                 if (!p)
 290                         return NULL;
 291                 memcpy(p, dp1, sz1);
 292                 /* the end node of the second device path has to be retained */
 293                 memcpy(p + sz1, dp2, sz2 + sizeof(END));
 294                 ret = p;
 295         }
 296
 297         return ret;
 298 }
 299
 300 struct efi_device_path *efi_dp_append_node(const struct efi_device_path *dp,
 301                                            const struct efi_device_path *node)
 302 {
 303         struct efi_device_path *ret;
 304
 305         if (!node && !dp) {
 306                 ret = efi_dp_dup(&END);
 307         } else if (!node) {
 308                 ret = efi_dp_dup(dp);
 309         } else if (!dp) {
 310                 size_t sz = node->length;
 311                 void *p = dp_alloc(sz + sizeof(END));
 312                 if (!p)
 313                         return NULL;
 314                 memcpy(p, node, sz);
 315                 memcpy(p + sz, &END, sizeof(END));
 316                 ret = p;
 317         } else {
 318                 /* both dp and node are non-null */
 319                 size_t sz = efi_dp_size(dp);
 320                 void *p = dp_alloc(sz + node->length + sizeof(END));
 321                 if (!p)
 322                         return NULL;
 323                 memcpy(p, dp, sz);
 324                 memcpy(p + sz, node, node->length);
 325                 memcpy(p + sz + node->length, &END, sizeof(END));
 326                 ret = p;
 327         }
 328
 329         return ret;
 330 }
 331
 332 struct efi_device_path *efi_dp_create_device_node(const u8 type,
 333                                                   const u8 sub_type,
 334                                                   const u16 length)
 335 {
 336         struct efi_device_path *ret;
 337
 338         if (length < sizeof(struct efi_device_path))
 339                 return NULL;
 340
 341         ret = dp_alloc(length);
 342         if (!ret)
 343                 return ret;
 344         ret->type = type;
 345         ret->sub_type = sub_type;
 346         ret->length = length;
 347         return ret;
 348 }
 349
 350 struct efi_device_path *efi_dp_append_instance(
 351                 const struct efi_device_path *dp,
 352                 const struct efi_device_path *dpi)
 353 {
 354         size_t sz, szi;
 355         struct efi_device_path *p, *ret;
 356
 357         if (!dpi)
 358                 return NULL;
 359         if (!dp)
 360                 return efi_dp_dup(dpi);
 361         sz = efi_dp_size(dp);
 362         szi = efi_dp_instance_size(dpi);
 363         p = dp_alloc(sz + szi + 2 * sizeof(END));
 364         if (!p)
 365                 return NULL;
 366         ret = p;
 367         memcpy(p, dp, sz + sizeof(END));
 368         p = (void *)p + sz;
 369         p->sub_type = DEVICE_PATH_SUB_TYPE_INSTANCE_END;
 370         p = (void *)p + sizeof(END);
 371         memcpy(p, dpi, szi);
 372         p = (void *)p + szi;
 373         memcpy(p, &END, sizeof(END));
 374         return ret;
 375 }
 376
 377 struct efi_device_path *efi_dp_get_next_instance(struct efi_device_path **dp,
 378                                                  efi_uintn_t *size)
 379 {
 380         size_t sz;
 381         struct efi_device_path *p;
 382
 383         if (size)
 384                 *size = 0;
 385         if (!dp || !*dp)
 386                 return NULL;
 387         sz = efi_dp_instance_size(*dp);
 388         p = dp_alloc(sz + sizeof(END));
 389         if (!p)
 390                 return NULL;
 391         memcpy(p, *dp, sz + sizeof(END));
 392         *dp = (void *)*dp + sz;
 393         if ((*dp)->sub_type == DEVICE_PATH_SUB_TYPE_INSTANCE_END)
 394                 *dp = (void *)*dp + sizeof(END);
 395         else
 396                 *dp = NULL;
 397         if (size)
 398                 *size = sz + sizeof(END);
 399         return p;
 400 }
 401
 402 bool efi_dp_is_multi_instance(const struct efi_device_path *dp)
 403 {
 404         const struct efi_device_path *p = dp;
 405
 406         if (!p)
 407                 return false;
 408         while (p->type != DEVICE_PATH_TYPE_END)
 409                 p = (void *)p + p->length;
 410         return p->sub_type == DEVICE_PATH_SUB_TYPE_INSTANCE_END;
 411 }
 412
 413 #ifdef CONFIG_DM
 414 /* size of device-path not including END node for device and all parents
 415  * up to the root device.
 416  */
 417 static unsigned dp_size(struct udevice *dev)
 418 {
 419         if (!dev || !dev->driver)
 420                 return sizeof(ROOT);
 421
 422         switch (dev->driver->id) {
 423         case UCLASS_ROOT:
 424         case UCLASS_SIMPLE_BUS:
 425                 /* stop traversing parents at this point: */
 426                 return sizeof(ROOT);
 427         case UCLASS_ETH:
 428                 return dp_size(dev->parent) +
 429                         sizeof(struct efi_device_path_mac_addr);
 430 #ifdef CONFIG_BLK
 431         case UCLASS_BLK:
 432                 switch (dev->parent->uclass->uc_drv->id) {
 433 #ifdef CONFIG_IDE
 434                 case UCLASS_IDE:
 435                         return dp_size(dev->parent) +
 436                                 sizeof(struct efi_device_path_atapi);
 437 #endif
 438 #if defined(CONFIG_SCSI) && defined(CONFIG_DM_SCSI)
 439                 case UCLASS_SCSI:
 440                         return dp_size(dev->parent) +
 441                                 sizeof(struct efi_device_path_scsi);
 442 #endif
 443 #if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
 444                 case UCLASS_MMC:
 445                         return dp_size(dev->parent) +
 446                                 sizeof(struct efi_device_path_sd_mmc_path);
 447 #endif
 448                 default:
 449                         return dp_size(dev->parent);
 450                 }
 451 #endif
 452 #if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
 453         case UCLASS_MMC:
 454                 return dp_size(dev->parent) +
 455                         sizeof(struct efi_device_path_sd_mmc_path);
 456 #endif
 457         case UCLASS_MASS_STORAGE:
 458         case UCLASS_USB_HUB:
 459                 return dp_size(dev->parent) +
 460                         sizeof(struct efi_device_path_usb_class);
 461         default:
 462                 /* just skip over unknown classes: */
 463                 return dp_size(dev->parent);
 464         }
 465 }
 466
 467 /*
 468  * Recursively build a device path.
 469  *
 470  * @buf         pointer to the end of the device path
 471  * @dev         device
 472  * @return      pointer to the end of the device path
 473  */
 474 static void *dp_fill(void *buf, struct udevice *dev)
 475 {
 476         if (!dev || !dev->driver)
 477                 return buf;
 478
 479         switch (dev->driver->id) {
 480         case UCLASS_ROOT:
 481         case UCLASS_SIMPLE_BUS: {
 482                 /* stop traversing parents at this point: */
 483                 struct efi_device_path_vendor *vdp = buf;
 484                 *vdp = ROOT;
 485                 return &vdp[1];
 486         }
 487 #ifdef CONFIG_DM_ETH
 488         case UCLASS_ETH: {
 489                 struct efi_device_path_mac_addr *dp =
 490                         dp_fill(buf, dev->parent);
 491                 struct eth_pdata *pdata = dev->platdata;
 492
 493                 dp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
 494                 dp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_MAC_ADDR;
 495                 dp->dp.length = sizeof(*dp);
 496                 memset(&dp->mac, 0, sizeof(dp->mac));
 497                 /* We only support IPv4 */
 498                 memcpy(&dp->mac, &pdata->enetaddr, ARP_HLEN);
 499                 /* Ethernet */
 500                 dp->if_type = 1;
 501                 return &dp[1];
 502         }
 503 #endif
 504 #ifdef CONFIG_BLK
 505         case UCLASS_BLK:
 506                 switch (dev->parent->uclass->uc_drv->id) {
 507 #ifdef CONFIG_IDE
 508                 case UCLASS_IDE: {
 509                         struct efi_device_path_atapi *dp =
 510                         dp_fill(buf, dev->parent);
 511                         struct blk_desc *desc = dev_get_uclass_platdata(dev);
 512
 513                         dp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
 514                         dp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_ATAPI;
 515                         dp->dp.length = sizeof(*dp);
 516                         dp->logical_unit_number = desc->devnum;
 517                         dp->primary_secondary = IDE_BUS(desc->devnum);
 518                         dp->slave_master = desc->devnum %
 519                                 (CONFIG_SYS_IDE_MAXDEVICE /
 520                                  CONFIG_SYS_IDE_MAXBUS);
 521                         return &dp[1];
 522                         }
 523 #endif
 524 #if defined(CONFIG_SCSI) && defined(CONFIG_DM_SCSI)
 525                 case UCLASS_SCSI: {
 526                         struct efi_device_path_scsi *dp =
 527                                 dp_fill(buf, dev->parent);
 528                         struct blk_desc *desc = dev_get_uclass_platdata(dev);
 529
 530                         dp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
 531                         dp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_SCSI;
 532                         dp->dp.length = sizeof(*dp);
 533                         dp->logical_unit_number = desc->lun;
 534                         dp->target_id = desc->target;
 535                         return &dp[1];
 536                         }
 537 #endif
 538 #if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
 539                 case UCLASS_MMC: {
 540                         struct efi_device_path_sd_mmc_path *sddp =
 541                                 dp_fill(buf, dev->parent);
 542                         struct blk_desc *desc = dev_get_uclass_platdata(dev);
 543
 544                         sddp->dp.type     = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
 545                         sddp->dp.sub_type = is_sd(desc) ?
 546                                 DEVICE_PATH_SUB_TYPE_MSG_SD :
 547                                 DEVICE_PATH_SUB_TYPE_MSG_MMC;
 548                         sddp->dp.length   = sizeof(*sddp);
 549                         sddp->slot_number = dev->seq;
 550                         return &sddp[1];
 551                         }
 552 #endif
 553                 default:
 554                         debug("%s(%u) %s: unhandled parent class: %s (%u)\n",
 555                               __FILE__, __LINE__, __func__,
 556                               dev->name, dev->parent->uclass->uc_drv->id);
 557                         return dp_fill(buf, dev->parent);
 558                 }
 559 #endif
 560 #if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
 561         case UCLASS_MMC: {
 562                 struct efi_device_path_sd_mmc_path *sddp =
 563                         dp_fill(buf, dev->parent);
 564                 struct mmc *mmc = mmc_get_mmc_dev(dev);
 565                 struct blk_desc *desc = mmc_get_blk_desc(mmc);
 566
 567                 sddp->dp.type     = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
 568                 sddp->dp.sub_type = is_sd(desc) ?
 569                         DEVICE_PATH_SUB_TYPE_MSG_SD :
 570                         DEVICE_PATH_SUB_TYPE_MSG_MMC;
 571                 sddp->dp.length   = sizeof(*sddp);
 572                 sddp->slot_number = dev->seq;
 573
 574                 return &sddp[1];
 575         }
 576 #endif
 577         case UCLASS_MASS_STORAGE:
 578         case UCLASS_USB_HUB: {
 579                 struct efi_device_path_usb_class *udp =
 580                         dp_fill(buf, dev->parent);
 581                 struct usb_device *udev = dev_get_parent_priv(dev);
 582                 struct usb_device_descriptor *desc = &udev->descriptor;
 583
 584                 udp->dp.type     = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
 585                 udp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_USB_CLASS;
 586                 udp->dp.length   = sizeof(*udp);
 587                 udp->vendor_id   = desc->idVendor;
 588                 udp->product_id  = desc->idProduct;
 589                 udp->device_class    = desc->bDeviceClass;
 590                 udp->device_subclass = desc->bDeviceSubClass;
 591                 udp->device_protocol = desc->bDeviceProtocol;
 592
 593                 return &udp[1];
 594         }
 595         default:
 596                 debug("%s(%u) %s: unhandled device class: %s (%u)\n",
 597                       __FILE__, __LINE__, __func__,
 598                       dev->name, dev->driver->id);
 599                 return dp_fill(buf, dev->parent);
 600         }
 601 }
 602
 603 /* Construct a device-path from a device: */
 604 struct efi_device_path *efi_dp_from_dev(struct udevice *dev)
 605 {
 606         void *buf, *start;
 607
 608         start = buf = dp_alloc(dp_size(dev) + sizeof(END));
 609         if (!buf)
 610                 return NULL;
 611         buf = dp_fill(buf, dev);
 612         *((struct efi_device_path *)buf) = END;
 613
 614         return start;
 615 }
 616 #endif
 617
 618 static unsigned dp_part_size(struct blk_desc *desc, int part)
 619 {
 620         unsigned dpsize;
 621
 622 #ifdef CONFIG_BLK
 623         {
 624                 struct udevice *dev;
 625                 int ret = blk_find_device(desc->if_type, desc->devnum, &dev);
 626
 627                 if (ret)
 628                         dev = desc->bdev->parent;
 629                 dpsize = dp_size(dev);
 630         }
 631 #else
 632         dpsize = sizeof(ROOT) + sizeof(struct efi_device_path_usb);
 633 #endif
 634
 635         if (part == 0) /* the actual disk, not a partition */
 636                 return dpsize;
 637
 638         if (desc->part_type == PART_TYPE_ISO)
 639                 dpsize += sizeof(struct efi_device_path_cdrom_path);
 640         else
 641                 dpsize += sizeof(struct efi_device_path_hard_drive_path);
 642
 643         return dpsize;
 644 }
 645
 646 /*
 647  * Create a device node for a block device partition.
 648  *
 649  * @buf         buffer to which the device path is written
 650  * @desc        block device descriptor
 651  * @part        partition number, 0 identifies a block device
 652  */
 653 static void *dp_part_node(void *buf, struct blk_desc *desc, int part)
 654 {
 655         disk_partition_t info;
 656
 657         part_get_info(desc, part, &info);
 658
 659         if (desc->part_type == PART_TYPE_ISO) {
 660                 struct efi_device_path_cdrom_path *cddp = buf;
 661
 662                 cddp->boot_entry = part;
 663                 cddp->dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
 664                 cddp->dp.sub_type = DEVICE_PATH_SUB_TYPE_CDROM_PATH;
 665                 cddp->dp.length = sizeof(*cddp);
 666                 cddp->partition_start = info.start;
 667                 cddp->partition_end = info.size;
 668
 669                 buf = &cddp[1];
 670         } else {
 671                 struct efi_device_path_hard_drive_path *hddp = buf;
 672
 673                 hddp->dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
 674                 hddp->dp.sub_type = DEVICE_PATH_SUB_TYPE_HARD_DRIVE_PATH;
 675                 hddp->dp.length = sizeof(*hddp);
 676                 hddp->partition_number = part;
 677                 hddp->partition_start = info.start;
 678                 hddp->partition_end = info.size;
 679                 if (desc->part_type == PART_TYPE_EFI)
 680                         hddp->partmap_type = 2;
 681                 else
 682                         hddp->partmap_type = 1;
 683
 684                 switch (desc->sig_type) {
 685                 case SIG_TYPE_NONE:
 686                 default:
 687                         hddp->signature_type = 0;
 688                         memset(hddp->partition_signature, 0,
 689                                sizeof(hddp->partition_signature));
 690                         break;
 691                 case SIG_TYPE_MBR:
 692                         hddp->signature_type = 1;
 693                         memset(hddp->partition_signature, 0,
 694                                sizeof(hddp->partition_signature));
 695                         memcpy(hddp->partition_signature, &desc->mbr_sig,
 696                                sizeof(desc->mbr_sig));
 697                         break;
 698                 case SIG_TYPE_GUID:
 699                         hddp->signature_type = 2;
 700                         memcpy(hddp->partition_signature, &desc->guid_sig,
 701                                sizeof(hddp->partition_signature));
 702                         break;
 703                 }
 704
 705                 buf = &hddp[1];
 706         }
 707
 708         return buf;
 709 }
 710
 711 /*
 712  * Create a device path for a block device or one of its partitions.
 713  *
 714  * @buf         buffer to which the device path is written
 715  * @desc        block device descriptor
 716  * @part        partition number, 0 identifies a block device
 717  */
 718 static void *dp_part_fill(void *buf, struct blk_desc *desc, int part)
 719 {
 720 #ifdef CONFIG_BLK
 721         {
 722                 struct udevice *dev;
 723                 int ret = blk_find_device(desc->if_type, desc->devnum, &dev);
 724
 725                 if (ret)
 726                         dev = desc->bdev->parent;
 727                 buf = dp_fill(buf, dev);
 728         }
 729 #else
 730         /*
 731          * We *could* make a more accurate path, by looking at if_type
 732          * and handling all the different cases like we do for non-
 733          * legacy (i.e. CONFIG_BLK=y) case. But most important thing
 734          * is just to have a unique device-path for if_type+devnum.
 735          * So map things to a fictitious USB device.
 736          */
 737         struct efi_device_path_usb *udp;
 738
 739         memcpy(buf, &ROOT, sizeof(ROOT));
 740         buf += sizeof(ROOT);
 741
 742         udp = buf;
 743         udp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
 744         udp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_USB;
 745         udp->dp.length = sizeof(*udp);
 746         udp->parent_port_number = desc->if_type;
 747         udp->usb_interface = desc->devnum;
 748         buf = &udp[1];
 749 #endif
 750
 751         if (part == 0) /* the actual disk, not a partition */
 752                 return buf;
 753
 754         return dp_part_node(buf, desc, part);
 755 }
 756
 757 /* Construct a device-path from a partition on a block device: */
 758 struct efi_device_path *efi_dp_from_part(struct blk_desc *desc, int part)
 759 {
 760         void *buf, *start;
 761
 762         start = buf = dp_alloc(dp_part_size(desc, part) + sizeof(END));
 763         if (!buf)
 764                 return NULL;
 765
 766         buf = dp_part_fill(buf, desc, part);
 767
 768         *((struct efi_device_path *)buf) = END;
 769
 770         return start;
 771 }
 772
 773 /*
 774  * Create a device node for a block device partition.
 775  *
 776  * @buf         buffer to which the device path is written
 777  * @desc        block device descriptor
 778  * @part        partition number, 0 identifies a block device
 779  */
 780 struct efi_device_path *efi_dp_part_node(struct blk_desc *desc, int part)
 781 {
 782         efi_uintn_t dpsize;
 783         void *buf;
 784
 785         if (desc->part_type == PART_TYPE_ISO)
 786                 dpsize = sizeof(struct efi_device_path_cdrom_path);
 787         else
 788                 dpsize = sizeof(struct efi_device_path_hard_drive_path);
 789         buf = dp_alloc(dpsize);
 790
 791         dp_part_node(buf, desc, part);
 792
 793         return buf;
 794 }
 795
 796 /* convert path to an UEFI style path (i.e. DOS style backslashes and UTF-16) */
 797 static void path_to_uefi(u16 *uefi, const char *path)
 798 {
 799         while (*path) {
 800                 char c = *(path++);
 801                 if (c == '/')
 802                         c = '\\';
 803                 *(uefi++) = c;
 804         }
 805         *uefi = '\0';
 806 }
 807
 808 /*
 809  * If desc is NULL, this creates a path with only the file component,
 810  * otherwise it creates a full path with both device and file components
 811  */
 812 struct efi_device_path *efi_dp_from_file(struct blk_desc *desc, int part,
 813                 const char *path)
 814 {
 815         struct efi_device_path_file_path *fp;
 816         void *buf, *start;
 817         unsigned dpsize = 0, fpsize;
 818
 819         if (desc)
 820                 dpsize = dp_part_size(desc, part);
 821
 822         fpsize = sizeof(struct efi_device_path) + 2 * (strlen(path) + 1);
 823         dpsize += fpsize;
 824
 825         start = buf = dp_alloc(dpsize + sizeof(END));
 826         if (!buf)
 827                 return NULL;
 828
 829         if (desc)
 830                 buf = dp_part_fill(buf, desc, part);
 831
 832         /* add file-path: */
 833         fp = buf;
 834         fp->dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
 835         fp->dp.sub_type = DEVICE_PATH_SUB_TYPE_FILE_PATH;
 836         fp->dp.length = fpsize;
 837         path_to_uefi(fp->str, path);
 838         buf += fpsize;
 839
 840         *((struct efi_device_path *)buf) = END;
 841
 842         return start;
 843 }
 844
 845 #ifdef CONFIG_NET
 846 struct efi_device_path *efi_dp_from_eth(void)
 847 {
 848 #ifndef CONFIG_DM_ETH
 849         struct efi_device_path_mac_addr *ndp;
 850 #endif
 851         void *buf, *start;
 852         unsigned dpsize = 0;
 853
 854         assert(eth_get_dev());
 855
 856 #ifdef CONFIG_DM_ETH
 857         dpsize += dp_size(eth_get_dev());
 858 #else
 859         dpsize += sizeof(ROOT);
 860         dpsize += sizeof(*ndp);
 861 #endif
 862
 863         start = buf = dp_alloc(dpsize + sizeof(END));
 864         if (!buf)
 865                 return NULL;
 866
 867 #ifdef CONFIG_DM_ETH
 868         buf = dp_fill(buf, eth_get_dev());
 869 #else
 870         memcpy(buf, &ROOT, sizeof(ROOT));
 871         buf += sizeof(ROOT);
 872
 873         ndp = buf;
 874         ndp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
 875         ndp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_MAC_ADDR;
 876         ndp->dp.length = sizeof(*ndp);
 877         ndp->if_type = 1; /* Ethernet */
 878         memcpy(ndp->mac.addr, eth_get_ethaddr(), ARP_HLEN);
 879         buf = &ndp[1];
 880 #endif
 881
 882         *((struct efi_device_path *)buf) = END;
 883
 884         return start;
 885 }
 886 #endif
 887
 888 /* Construct a device-path for memory-mapped image */
 889 struct efi_device_path *efi_dp_from_mem(uint32_t memory_type,
 890                                         uint64_t start_address,
 891                                         uint64_t end_address)
 892 {
 893         struct efi_device_path_memory *mdp;
 894         void *buf, *start;
 895
 896         start = buf = dp_alloc(sizeof(*mdp) + sizeof(END));
 897         if (!buf)
 898                 return NULL;
 899
 900         mdp = buf;
 901         mdp->dp.type = DEVICE_PATH_TYPE_HARDWARE_DEVICE;
 902         mdp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MEMORY;
 903         mdp->dp.length = sizeof(*mdp);
 904         mdp->memory_type = memory_type;
 905         mdp->start_address = start_address;
 906         mdp->end_address = end_address;
 907         buf = &mdp[1];
 908
 909         *((struct efi_device_path *)buf) = END;
 910
 911         return start;
 912 }
 913
 914 /**
 915  * efi_dp_split_file_path() - split of relative file path from device path
 916  *
 917  * Given a device path indicating a file on a device, separate the device
 918  * path in two: the device path of the actual device and the file path
 919  * relative to this device.
 920  *
 921  * @full_path:          device path including device and file path
 922  * @device_path:        path of the device
 923  * @file_path:          relative path of the file or NULL if there is none
 924  * Return:              status code
 925  */
 926 efi_status_t efi_dp_split_file_path(struct efi_device_path *full_path,
 927                                     struct efi_device_path **device_path,
 928                                     struct efi_device_path **file_path)
 929 {
 930         struct efi_device_path *p, *dp, *fp = NULL;
 931
 932         *device_path = NULL;
 933         *file_path = NULL;
 934         dp = efi_dp_dup(full_path);
 935         if (!dp)
 936                 return EFI_OUT_OF_RESOURCES;
 937         p = dp;
 938         while (!EFI_DP_TYPE(p, MEDIA_DEVICE, FILE_PATH)) {
 939                 p = efi_dp_next(p);
 940                 if (!p)
 941                         goto out;
 942         }
 943         fp = efi_dp_dup(p);
 944         if (!fp)
 945                 return EFI_OUT_OF_RESOURCES;
 946         p->type = DEVICE_PATH_TYPE_END;
 947         p->sub_type = DEVICE_PATH_SUB_TYPE_END;
 948         p->length = sizeof(*p);
 949
 950 out:
 951         *device_path = dp;
 952         *file_path = fp;
 953         return EFI_SUCCESS;
 954 }
 955
 956 efi_status_t efi_dp_from_name(const char *dev, const char *devnr,
 957                               const char *path,
 958                               struct efi_device_path **device,
 959                               struct efi_device_path **file)
 960 {
 961         int is_net;
 962         struct blk_desc *desc = NULL;
 963         disk_partition_t fs_partition;
 964         int part = 0;
 965         char filename[32] = { 0 }; /* dp->str is u16[32] long */
 966         char *s;
 967
 968         if (path && !file)
 969                 return EFI_INVALID_PARAMETER;
 970
 971         is_net = !strcmp(dev, "Net");
 972         if (!is_net) {
 973                 part = blk_get_device_part_str(dev, devnr, &desc, &fs_partition,
 974                                                1);
 975                 if (part < 0 || !desc)
 976                         return EFI_INVALID_PARAMETER;
 977
 978                 if (device)
 979                         *device = efi_dp_from_part(desc, part);
 980         } else {
 981 #ifdef CONFIG_NET
 982                 if (device)
 983                         *device = efi_dp_from_eth();
 984 #endif
 985         }
 986
 987         if (!path)
 988                 return EFI_SUCCESS;
 989
 990         snprintf(filename, sizeof(filename), "%s", path);
 991         /* DOS style file path: */
 992         s = filename;
 993         while ((s = strchr(s, '/')))
 994                 *s++ = '\\';
 995         *file = efi_dp_from_file(((!is_net && device) ? desc : NULL),
 996                                  part, filename);
 997
 998         return EFI_SUCCESS;
 999 }