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 #include <sandboxblockdev.h>
  16 #include <asm-generic/unaligned.h>
  17
  18 #ifdef CONFIG_SANDBOX
  19 const efi_guid_t efi_guid_host_dev = U_BOOT_HOST_DEV_GUID;
  20 #endif
  21
  22 /* template END node: */
  23 static const struct efi_device_path END = {
  24         .type     = DEVICE_PATH_TYPE_END,
  25         .sub_type = DEVICE_PATH_SUB_TYPE_END,
  26         .length   = sizeof(END),
  27 };
  28
  29 /* template ROOT node: */
  30 static const struct efi_device_path_vendor ROOT = {
  31         .dp = {
  32                 .type     = DEVICE_PATH_TYPE_HARDWARE_DEVICE,
  33                 .sub_type = DEVICE_PATH_SUB_TYPE_VENDOR,
  34                 .length   = sizeof(ROOT),
  35         },
  36         .guid = U_BOOT_GUID,
  37 };
  38
  39 #if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
  40 /*
  41  * Determine if an MMC device is an SD card.
  42  *
  43  * @desc        block device descriptor
  44  * @return      true if the device is an SD card
  45  */
  46 static bool is_sd(struct blk_desc *desc)
  47 {
  48         struct mmc *mmc = find_mmc_device(desc->devnum);
  49
  50         if (!mmc)
  51                 return false;
  52
  53         return IS_SD(mmc) != 0U;
  54 }
  55 #endif
  56
  57 static void *dp_alloc(size_t sz)
  58 {
  59         void *buf;
  60
  61         if (efi_allocate_pool(EFI_ALLOCATE_ANY_PAGES, sz, &buf) !=
  62             EFI_SUCCESS) {
  63                 debug("EFI: ERROR: out of memory in %s\n", __func__);
  64                 return NULL;
  65         }
  66
  67         memset(buf, 0, sz);
  68         return buf;
  69 }
  70
  71 /*
  72  * Iterate to next block in device-path, terminating (returning NULL)
  73  * at /End* node.
  74  */
  75 struct efi_device_path *efi_dp_next(const struct efi_device_path *dp)
  76 {
  77         if (dp == NULL)
  78                 return NULL;
  79         if (dp->type == DEVICE_PATH_TYPE_END)
  80                 return NULL;
  81         dp = ((void *)dp) + dp->length;
  82         if (dp->type == DEVICE_PATH_TYPE_END)
  83                 return NULL;
  84         return (struct efi_device_path *)dp;
  85 }
  86
  87 /*
  88  * Compare two device-paths, stopping when the shorter of the two hits
  89  * an End* node. This is useful to, for example, compare a device-path
  90  * representing a device with one representing a file on the device, or
  91  * a device with a parent device.
  92  */
  93 int efi_dp_match(const struct efi_device_path *a,
  94                  const struct efi_device_path *b)
  95 {
  96         while (1) {
  97                 int ret;
  98
  99                 ret = memcmp(&a->length, &b->length, sizeof(a->length));
 100                 if (ret)
 101                         return ret;
 102
 103                 ret = memcmp(a, b, a->length);
 104                 if (ret)
 105                         return ret;
 106
 107                 a = efi_dp_next(a);
 108                 b = efi_dp_next(b);
 109
 110                 if (!a || !b)
 111                         return 0;
 112         }
 113 }
 114
 115 /*
 116  * We can have device paths that start with a USB WWID or a USB Class node,
 117  * and a few other cases which don't encode the full device path with bus
 118  * hierarchy:
 119  *
 120  *   - MESSAGING:USB_WWID
 121  *   - MESSAGING:USB_CLASS
 122  *   - MEDIA:FILE_PATH
 123  *   - MEDIA:HARD_DRIVE
 124  *   - MESSAGING:URI
 125  *
 126  * See UEFI spec (section 3.1.2, about short-form device-paths)
 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,
 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         if (length < sizeof(struct efi_device_path))
 345                 return NULL;
 346
 347         ret = dp_alloc(length);
 348         if (!ret)
 349                 return ret;
 350         ret->type = type;
 351         ret->sub_type = sub_type;
 352         ret->length = length;
 353         return ret;
 354 }
 355
 356 struct efi_device_path *efi_dp_append_instance(
 357                 const struct efi_device_path *dp,
 358                 const struct efi_device_path *dpi)
 359 {
 360         size_t sz, szi;
 361         struct efi_device_path *p, *ret;
 362
 363         if (!dpi)
 364                 return NULL;
 365         if (!dp)
 366                 return efi_dp_dup(dpi);
 367         sz = efi_dp_size(dp);
 368         szi = efi_dp_instance_size(dpi);
 369         p = dp_alloc(sz + szi + 2 * sizeof(END));
 370         if (!p)
 371                 return NULL;
 372         ret = p;
 373         memcpy(p, dp, sz + sizeof(END));
 374         p = (void *)p + sz;
 375         p->sub_type = DEVICE_PATH_SUB_TYPE_INSTANCE_END;
 376         p = (void *)p + sizeof(END);
 377         memcpy(p, dpi, szi);
 378         p = (void *)p + szi;
 379         memcpy(p, &END, sizeof(END));
 380         return ret;
 381 }
 382
 383 struct efi_device_path *efi_dp_get_next_instance(struct efi_device_path **dp,
 384                                                  efi_uintn_t *size)
 385 {
 386         size_t sz;
 387         struct efi_device_path *p;
 388
 389         if (size)
 390                 *size = 0;
 391         if (!dp || !*dp)
 392                 return NULL;
 393         sz = efi_dp_instance_size(*dp);
 394         p = dp_alloc(sz + sizeof(END));
 395         if (!p)
 396                 return NULL;
 397         memcpy(p, *dp, sz + sizeof(END));
 398         *dp = (void *)*dp + sz;
 399         if ((*dp)->sub_type == DEVICE_PATH_SUB_TYPE_INSTANCE_END)
 400                 *dp = (void *)*dp + sizeof(END);
 401         else
 402                 *dp = NULL;
 403         if (size)
 404                 *size = sz + sizeof(END);
 405         return p;
 406 }
 407
 408 bool efi_dp_is_multi_instance(const struct efi_device_path *dp)
 409 {
 410         const struct efi_device_path *p = dp;
 411
 412         if (!p)
 413                 return false;
 414         while (p->type != DEVICE_PATH_TYPE_END)
 415                 p = (void *)p + p->length;
 416         return p->sub_type == DEVICE_PATH_SUB_TYPE_INSTANCE_END;
 417 }
 418
 419 #ifdef CONFIG_DM
 420 /* size of device-path not including END node for device and all parents
 421  * up to the root device.
 422  */
 423 static unsigned dp_size(struct udevice *dev)
 424 {
 425         if (!dev || !dev->driver)
 426                 return sizeof(ROOT);
 427
 428         switch (dev->driver->id) {
 429         case UCLASS_ROOT:
 430         case UCLASS_SIMPLE_BUS:
 431                 /* stop traversing parents at this point: */
 432                 return sizeof(ROOT);
 433         case UCLASS_ETH:
 434                 return dp_size(dev->parent) +
 435                         sizeof(struct efi_device_path_mac_addr);
 436 #ifdef CONFIG_BLK
 437         case UCLASS_BLK:
 438                 switch (dev->parent->uclass->uc_drv->id) {
 439 #ifdef CONFIG_IDE
 440                 case UCLASS_IDE:
 441                         return dp_size(dev->parent) +
 442                                 sizeof(struct efi_device_path_atapi);
 443 #endif
 444 #if defined(CONFIG_SCSI) && defined(CONFIG_DM_SCSI)
 445                 case UCLASS_SCSI:
 446                         return dp_size(dev->parent) +
 447                                 sizeof(struct efi_device_path_scsi);
 448 #endif
 449 #if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
 450                 case UCLASS_MMC:
 451                         return dp_size(dev->parent) +
 452                                 sizeof(struct efi_device_path_sd_mmc_path);
 453 #endif
 454 #ifdef CONFIG_SANDBOX
 455                 case UCLASS_ROOT:
 456                          /*
 457                           * Sandbox's host device will be represented
 458                           * as vendor device with extra one byte for
 459                           * device number
 460                           */
 461                         return dp_size(dev->parent)
 462                                 + sizeof(struct efi_device_path_vendor) + 1;
 463 #endif
 464                 default:
 465                         return dp_size(dev->parent);
 466                 }
 467 #endif
 468 #if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
 469         case UCLASS_MMC:
 470                 return dp_size(dev->parent) +
 471                         sizeof(struct efi_device_path_sd_mmc_path);
 472 #endif
 473         case UCLASS_MASS_STORAGE:
 474         case UCLASS_USB_HUB:
 475                 return dp_size(dev->parent) +
 476                         sizeof(struct efi_device_path_usb_class);
 477         default:
 478                 /* just skip over unknown classes: */
 479                 return dp_size(dev->parent);
 480         }
 481 }
 482
 483 /*
 484  * Recursively build a device path.
 485  *
 486  * @buf         pointer to the end of the device path
 487  * @dev         device
 488  * @return      pointer to the end of the device path
 489  */
 490 static void *dp_fill(void *buf, struct udevice *dev)
 491 {
 492         if (!dev || !dev->driver)
 493                 return buf;
 494
 495         switch (dev->driver->id) {
 496         case UCLASS_ROOT:
 497         case UCLASS_SIMPLE_BUS: {
 498                 /* stop traversing parents at this point: */
 499                 struct efi_device_path_vendor *vdp = buf;
 500                 *vdp = ROOT;
 501                 return &vdp[1];
 502         }
 503 #ifdef CONFIG_DM_ETH
 504         case UCLASS_ETH: {
 505                 struct efi_device_path_mac_addr *dp =
 506                         dp_fill(buf, dev->parent);
 507                 struct eth_pdata *pdata = dev->platdata;
 508
 509                 dp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
 510                 dp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_MAC_ADDR;
 511                 dp->dp.length = sizeof(*dp);
 512                 memset(&dp->mac, 0, sizeof(dp->mac));
 513                 /* We only support IPv4 */
 514                 memcpy(&dp->mac, &pdata->enetaddr, ARP_HLEN);
 515                 /* Ethernet */
 516                 dp->if_type = 1;
 517                 return &dp[1];
 518         }
 519 #endif
 520 #ifdef CONFIG_BLK
 521         case UCLASS_BLK:
 522                 switch (dev->parent->uclass->uc_drv->id) {
 523 #ifdef CONFIG_SANDBOX
 524                 case UCLASS_ROOT: {
 525                         /* stop traversing parents at this point: */
 526                         struct efi_device_path_vendor *dp = buf;
 527                         struct blk_desc *desc = dev_get_uclass_platdata(dev);
 528
 529                         dp_fill(buf, dev->parent);
 530                         dp = buf;
 531                         ++dp;
 532                         dp->dp.type = DEVICE_PATH_TYPE_HARDWARE_DEVICE;
 533                         dp->dp.sub_type = DEVICE_PATH_SUB_TYPE_VENDOR;
 534                         dp->dp.length = sizeof(*dp) + 1;
 535                         memcpy(&dp->guid, &efi_guid_host_dev,
 536                                sizeof(efi_guid_t));
 537                         dp->vendor_data[0] = desc->devnum;
 538                         return &dp->vendor_data[1];
 539                         }
 540 #endif
 541 #ifdef CONFIG_IDE
 542                 case UCLASS_IDE: {
 543                         struct efi_device_path_atapi *dp =
 544                         dp_fill(buf, dev->parent);
 545                         struct blk_desc *desc = dev_get_uclass_platdata(dev);
 546
 547                         dp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
 548                         dp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_ATAPI;
 549                         dp->dp.length = sizeof(*dp);
 550                         dp->logical_unit_number = desc->devnum;
 551                         dp->primary_secondary = IDE_BUS(desc->devnum);
 552                         dp->slave_master = desc->devnum %
 553                                 (CONFIG_SYS_IDE_MAXDEVICE /
 554                                  CONFIG_SYS_IDE_MAXBUS);
 555                         return &dp[1];
 556                         }
 557 #endif
 558 #if defined(CONFIG_SCSI) && defined(CONFIG_DM_SCSI)
 559                 case UCLASS_SCSI: {
 560                         struct efi_device_path_scsi *dp =
 561                                 dp_fill(buf, dev->parent);
 562                         struct blk_desc *desc = dev_get_uclass_platdata(dev);
 563
 564                         dp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
 565                         dp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_SCSI;
 566                         dp->dp.length = sizeof(*dp);
 567                         dp->logical_unit_number = desc->lun;
 568                         dp->target_id = desc->target;
 569                         return &dp[1];
 570                         }
 571 #endif
 572 #if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
 573                 case UCLASS_MMC: {
 574                         struct efi_device_path_sd_mmc_path *sddp =
 575                                 dp_fill(buf, dev->parent);
 576                         struct blk_desc *desc = dev_get_uclass_platdata(dev);
 577
 578                         sddp->dp.type     = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
 579                         sddp->dp.sub_type = is_sd(desc) ?
 580                                 DEVICE_PATH_SUB_TYPE_MSG_SD :
 581                                 DEVICE_PATH_SUB_TYPE_MSG_MMC;
 582                         sddp->dp.length   = sizeof(*sddp);
 583                         sddp->slot_number = dev->seq;
 584                         return &sddp[1];
 585                         }
 586 #endif
 587                 default:
 588                         debug("%s(%u) %s: unhandled parent class: %s (%u)\n",
 589                               __FILE__, __LINE__, __func__,
 590                               dev->name, dev->parent->uclass->uc_drv->id);
 591                         return dp_fill(buf, dev->parent);
 592                 }
 593 #endif
 594 #if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
 595         case UCLASS_MMC: {
 596                 struct efi_device_path_sd_mmc_path *sddp =
 597                         dp_fill(buf, dev->parent);
 598                 struct mmc *mmc = mmc_get_mmc_dev(dev);
 599                 struct blk_desc *desc = mmc_get_blk_desc(mmc);
 600
 601                 sddp->dp.type     = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
 602                 sddp->dp.sub_type = is_sd(desc) ?
 603                         DEVICE_PATH_SUB_TYPE_MSG_SD :
 604                         DEVICE_PATH_SUB_TYPE_MSG_MMC;
 605                 sddp->dp.length   = sizeof(*sddp);
 606                 sddp->slot_number = dev->seq;
 607
 608                 return &sddp[1];
 609         }
 610 #endif
 611         case UCLASS_MASS_STORAGE:
 612         case UCLASS_USB_HUB: {
 613                 struct efi_device_path_usb_class *udp =
 614                         dp_fill(buf, dev->parent);
 615                 struct usb_device *udev = dev_get_parent_priv(dev);
 616                 struct usb_device_descriptor *desc = &udev->descriptor;
 617
 618                 udp->dp.type     = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
 619                 udp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_USB_CLASS;
 620                 udp->dp.length   = sizeof(*udp);
 621                 udp->vendor_id   = desc->idVendor;
 622                 udp->product_id  = desc->idProduct;
 623                 udp->device_class    = desc->bDeviceClass;
 624                 udp->device_subclass = desc->bDeviceSubClass;
 625                 udp->device_protocol = desc->bDeviceProtocol;
 626
 627                 return &udp[1];
 628         }
 629         default:
 630                 debug("%s(%u) %s: unhandled device class: %s (%u)\n",
 631                       __FILE__, __LINE__, __func__,
 632                       dev->name, dev->driver->id);
 633                 return dp_fill(buf, dev->parent);
 634         }
 635 }
 636
 637 /* Construct a device-path from a device: */
 638 struct efi_device_path *efi_dp_from_dev(struct udevice *dev)
 639 {
 640         void *buf, *start;
 641
 642         start = buf = dp_alloc(dp_size(dev) + sizeof(END));
 643         if (!buf)
 644                 return NULL;
 645         buf = dp_fill(buf, dev);
 646         *((struct efi_device_path *)buf) = END;
 647
 648         return start;
 649 }
 650 #endif
 651
 652 static unsigned dp_part_size(struct blk_desc *desc, int part)
 653 {
 654         unsigned dpsize;
 655
 656 #ifdef CONFIG_BLK
 657         {
 658                 struct udevice *dev;
 659                 int ret = blk_find_device(desc->if_type, desc->devnum, &dev);
 660
 661                 if (ret)
 662                         dev = desc->bdev->parent;
 663                 dpsize = dp_size(dev);
 664         }
 665 #else
 666         dpsize = sizeof(ROOT) + sizeof(struct efi_device_path_usb);
 667 #endif
 668
 669         if (part == 0) /* the actual disk, not a partition */
 670                 return dpsize;
 671
 672         if (desc->part_type == PART_TYPE_ISO)
 673                 dpsize += sizeof(struct efi_device_path_cdrom_path);
 674         else
 675                 dpsize += sizeof(struct efi_device_path_hard_drive_path);
 676
 677         return dpsize;
 678 }
 679
 680 /*
 681  * Create a device node for a block device partition.
 682  *
 683  * @buf         buffer to which the device path is written
 684  * @desc        block device descriptor
 685  * @part        partition number, 0 identifies a block device
 686  */
 687 static void *dp_part_node(void *buf, struct blk_desc *desc, int part)
 688 {
 689         disk_partition_t info;
 690
 691         part_get_info(desc, part, &info);
 692
 693         if (desc->part_type == PART_TYPE_ISO) {
 694                 struct efi_device_path_cdrom_path *cddp = buf;
 695
 696                 cddp->boot_entry = part;
 697                 cddp->dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
 698                 cddp->dp.sub_type = DEVICE_PATH_SUB_TYPE_CDROM_PATH;
 699                 cddp->dp.length = sizeof(*cddp);
 700                 cddp->partition_start = info.start;
 701                 cddp->partition_size = info.size;
 702
 703                 buf = &cddp[1];
 704         } else {
 705                 struct efi_device_path_hard_drive_path *hddp = buf;
 706
 707                 hddp->dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
 708                 hddp->dp.sub_type = DEVICE_PATH_SUB_TYPE_HARD_DRIVE_PATH;
 709                 hddp->dp.length = sizeof(*hddp);
 710                 hddp->partition_number = part;
 711                 hddp->partition_start = info.start;
 712                 hddp->partition_end = info.size;
 713                 if (desc->part_type == PART_TYPE_EFI)
 714                         hddp->partmap_type = 2;
 715                 else
 716                         hddp->partmap_type = 1;
 717
 718                 switch (desc->sig_type) {
 719                 case SIG_TYPE_NONE:
 720                 default:
 721                         hddp->signature_type = 0;
 722                         memset(hddp->partition_signature, 0,
 723                                sizeof(hddp->partition_signature));
 724                         break;
 725                 case SIG_TYPE_MBR:
 726                         hddp->signature_type = 1;
 727                         memset(hddp->partition_signature, 0,
 728                                sizeof(hddp->partition_signature));
 729                         memcpy(hddp->partition_signature, &desc->mbr_sig,
 730                                sizeof(desc->mbr_sig));
 731                         break;
 732                 case SIG_TYPE_GUID:
 733                         hddp->signature_type = 2;
 734                         memcpy(hddp->partition_signature, &desc->guid_sig,
 735                                sizeof(hddp->partition_signature));
 736                         break;
 737                 }
 738
 739                 buf = &hddp[1];
 740         }
 741
 742         return buf;
 743 }
 744
 745 /*
 746  * Create a device path for a block device or one of its partitions.
 747  *
 748  * @buf         buffer to which the device path is written
 749  * @desc        block device descriptor
 750  * @part        partition number, 0 identifies a block device
 751  */
 752 static void *dp_part_fill(void *buf, struct blk_desc *desc, int part)
 753 {
 754 #ifdef CONFIG_BLK
 755         {
 756                 struct udevice *dev;
 757                 int ret = blk_find_device(desc->if_type, desc->devnum, &dev);
 758
 759                 if (ret)
 760                         dev = desc->bdev->parent;
 761                 buf = dp_fill(buf, dev);
 762         }
 763 #else
 764         /*
 765          * We *could* make a more accurate path, by looking at if_type
 766          * and handling all the different cases like we do for non-
 767          * legacy (i.e. CONFIG_BLK=y) case. But most important thing
 768          * is just to have a unique device-path for if_type+devnum.
 769          * So map things to a fictitious USB device.
 770          */
 771         struct efi_device_path_usb *udp;
 772
 773         memcpy(buf, &ROOT, sizeof(ROOT));
 774         buf += sizeof(ROOT);
 775
 776         udp = buf;
 777         udp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
 778         udp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_USB;
 779         udp->dp.length = sizeof(*udp);
 780         udp->parent_port_number = desc->if_type;
 781         udp->usb_interface = desc->devnum;
 782         buf = &udp[1];
 783 #endif
 784
 785         if (part == 0) /* the actual disk, not a partition */
 786                 return buf;
 787
 788         return dp_part_node(buf, desc, part);
 789 }
 790
 791 /* Construct a device-path from a partition on a block device: */
 792 struct efi_device_path *efi_dp_from_part(struct blk_desc *desc, int part)
 793 {
 794         void *buf, *start;
 795
 796         start = buf = dp_alloc(dp_part_size(desc, part) + sizeof(END));
 797         if (!buf)
 798                 return NULL;
 799
 800         buf = dp_part_fill(buf, desc, part);
 801
 802         *((struct efi_device_path *)buf) = END;
 803
 804         return start;
 805 }
 806
 807 /*
 808  * Create a device node for a block device partition.
 809  *
 810  * @buf         buffer to which the device path is written
 811  * @desc        block device descriptor
 812  * @part        partition number, 0 identifies a block device
 813  */
 814 struct efi_device_path *efi_dp_part_node(struct blk_desc *desc, int part)
 815 {
 816         efi_uintn_t dpsize;
 817         void *buf;
 818
 819         if (desc->part_type == PART_TYPE_ISO)
 820                 dpsize = sizeof(struct efi_device_path_cdrom_path);
 821         else
 822                 dpsize = sizeof(struct efi_device_path_hard_drive_path);
 823         buf = dp_alloc(dpsize);
 824
 825         dp_part_node(buf, desc, part);
 826
 827         return buf;
 828 }
 829
 830 /**
 831  * path_to_uefi() - convert UTF-8 path to an UEFI style path
 832  *
 833  * Convert UTF-8 path to a UEFI style path (i.e. with backslashes as path
 834  * separators and UTF-16).
 835  *
 836  * @src:        source buffer
 837  * @uefi:       target buffer, possibly unaligned
 838  */
 839 static void path_to_uefi(void *uefi, const char *src)
 840 {
 841         u16 *pos = uefi;
 842
 843         /*
 844          * efi_set_bootdev() calls this routine indirectly before the UEFI
 845          * subsystem is initialized. So we cannot assume unaligned access to be
 846          * enabled.
 847          */
 848         allow_unaligned();
 849
 850         while (*src) {
 851                 s32 code = utf8_get(&src);
 852
 853                 if (code < 0)
 854                         code = '?';
 855                 else if (code == '/')
 856                         code = '\\';
 857                 utf16_put(code, &pos);
 858         }
 859         *pos = 0;
 860 }
 861
 862 /*
 863  * If desc is NULL, this creates a path with only the file component,
 864  * otherwise it creates a full path with both device and file components
 865  */
 866 struct efi_device_path *efi_dp_from_file(struct blk_desc *desc, int part,
 867                 const char *path)
 868 {
 869         struct efi_device_path_file_path *fp;
 870         void *buf, *start;
 871         unsigned dpsize = 0, fpsize;
 872
 873         if (desc)
 874                 dpsize = dp_part_size(desc, part);
 875
 876         fpsize = sizeof(struct efi_device_path) +
 877                  2 * (utf8_utf16_strlen(path) + 1);
 878         dpsize += fpsize;
 879
 880         start = buf = dp_alloc(dpsize + sizeof(END));
 881         if (!buf)
 882                 return NULL;
 883
 884         if (desc)
 885                 buf = dp_part_fill(buf, desc, part);
 886
 887         /* add file-path: */
 888         fp = buf;
 889         fp->dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
 890         fp->dp.sub_type = DEVICE_PATH_SUB_TYPE_FILE_PATH;
 891         fp->dp.length = fpsize;
 892         path_to_uefi(fp->str, path);
 893         buf += fpsize;
 894
 895         *((struct efi_device_path *)buf) = END;
 896
 897         return start;
 898 }
 899
 900 #ifdef CONFIG_NET
 901 struct efi_device_path *efi_dp_from_eth(void)
 902 {
 903 #ifndef CONFIG_DM_ETH
 904         struct efi_device_path_mac_addr *ndp;
 905 #endif
 906         void *buf, *start;
 907         unsigned dpsize = 0;
 908
 909         assert(eth_get_dev());
 910
 911 #ifdef CONFIG_DM_ETH
 912         dpsize += dp_size(eth_get_dev());
 913 #else
 914         dpsize += sizeof(ROOT);
 915         dpsize += sizeof(*ndp);
 916 #endif
 917
 918         start = buf = dp_alloc(dpsize + sizeof(END));
 919         if (!buf)
 920                 return NULL;
 921
 922 #ifdef CONFIG_DM_ETH
 923         buf = dp_fill(buf, eth_get_dev());
 924 #else
 925         memcpy(buf, &ROOT, sizeof(ROOT));
 926         buf += sizeof(ROOT);
 927
 928         ndp = buf;
 929         ndp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
 930         ndp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_MAC_ADDR;
 931         ndp->dp.length = sizeof(*ndp);
 932         ndp->if_type = 1; /* Ethernet */
 933         memcpy(ndp->mac.addr, eth_get_ethaddr(), ARP_HLEN);
 934         buf = &ndp[1];
 935 #endif
 936
 937         *((struct efi_device_path *)buf) = END;
 938
 939         return start;
 940 }
 941 #endif
 942
 943 /* Construct a device-path for memory-mapped image */
 944 struct efi_device_path *efi_dp_from_mem(uint32_t memory_type,
 945                                         uint64_t start_address,
 946                                         uint64_t end_address)
 947 {
 948         struct efi_device_path_memory *mdp;
 949         void *buf, *start;
 950
 951         start = buf = dp_alloc(sizeof(*mdp) + sizeof(END));
 952         if (!buf)
 953                 return NULL;
 954
 955         mdp = buf;
 956         mdp->dp.type = DEVICE_PATH_TYPE_HARDWARE_DEVICE;
 957         mdp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MEMORY;
 958         mdp->dp.length = sizeof(*mdp);
 959         mdp->memory_type = memory_type;
 960         mdp->start_address = start_address;
 961         mdp->end_address = end_address;
 962         buf = &mdp[1];
 963
 964         *((struct efi_device_path *)buf) = END;
 965
 966         return start;
 967 }
 968
 969 /**
 970  * efi_dp_split_file_path() - split of relative file path from device path
 971  *
 972  * Given a device path indicating a file on a device, separate the device
 973  * path in two: the device path of the actual device and the file path
 974  * relative to this device.
 975  *
 976  * @full_path:          device path including device and file path
 977  * @device_path:        path of the device
 978  * @file_path:          relative path of the file or NULL if there is none
 979  * Return:              status code
 980  */
 981 efi_status_t efi_dp_split_file_path(struct efi_device_path *full_path,
 982                                     struct efi_device_path **device_path,
 983                                     struct efi_device_path **file_path)
 984 {
 985         struct efi_device_path *p, *dp, *fp = NULL;
 986
 987         *device_path = NULL;
 988         *file_path = NULL;
 989         dp = efi_dp_dup(full_path);
 990         if (!dp)
 991                 return EFI_OUT_OF_RESOURCES;
 992         p = dp;
 993         while (!EFI_DP_TYPE(p, MEDIA_DEVICE, FILE_PATH)) {
 994                 p = efi_dp_next(p);
 995                 if (!p)
 996                         goto out;
 997         }
 998         fp = efi_dp_dup(p);
 999         if (!fp)
1000                 return EFI_OUT_OF_RESOURCES;
1001         p->type = DEVICE_PATH_TYPE_END;
1002         p->sub_type = DEVICE_PATH_SUB_TYPE_END;
1003         p->length = sizeof(*p);
1004
1005 out:
1006         *device_path = dp;
1007         *file_path = fp;
1008         return EFI_SUCCESS;
1009 }
1010
1011 efi_status_t efi_dp_from_name(const char *dev, const char *devnr,
1012                               const char *path,
1013                               struct efi_device_path **device,
1014                               struct efi_device_path **file)
1015 {
1016         int is_net;
1017         struct blk_desc *desc = NULL;
1018         disk_partition_t fs_partition;
1019         int part = 0;
1020         char filename[32] = { 0 }; /* dp->str is u16[32] long */
1021         char *s;
1022
1023         if (path && !file)
1024                 return EFI_INVALID_PARAMETER;
1025
1026         is_net = !strcmp(dev, "Net");
1027         if (!is_net) {
1028                 part = blk_get_device_part_str(dev, devnr, &desc, &fs_partition,
1029                                                1);
1030                 if (part < 0 || !desc)
1031                         return EFI_INVALID_PARAMETER;
1032
1033                 if (device)
1034                         *device = efi_dp_from_part(desc, part);
1035         } else {
1036 #ifdef CONFIG_NET
1037                 if (device)
1038                         *device = efi_dp_from_eth();
1039 #endif
1040         }
1041
1042         if (!path)
1043                 return EFI_SUCCESS;
1044
1045         snprintf(filename, sizeof(filename), "%s", path);
1046         /* DOS style file path: */
1047         s = filename;
1048         while ((s = strchr(s, '/')))
1049                 *s++ = '\\';
1050         *file = efi_dp_from_file(((!is_net && device) ? desc : NULL),
1051                                  part, filename);
1052
1053         return EFI_SUCCESS;
1054 }