cmd/bootefi.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  *  EFI application loader
   4  *
   5  *  Copyright (c) 2016 Alexander Graf
   6  */
   7
   8 #define LOG_CATEGORY LOGC_EFI
   9
  10 #include <common.h>
  11 #include <charset.h>
  12 #include <command.h>
  13 #include <dm.h>
  14 #include <efi_loader.h>
  15 #include <efi_selftest.h>
  16 #include <env.h>
  17 #include <errno.h>
  18 #include <image.h>
  19 #include <log.h>
  20 #include <malloc.h>
  21 #include <linux/libfdt.h>
  22 #include <linux/libfdt_env.h>
  23 #include <mapmem.h>
  24 #include <memalign.h>
  25 #include <asm-generic/sections.h>
  26 #include <linux/linkage.h>
  27
  28 DECLARE_GLOBAL_DATA_PTR;
  29
  30 static struct efi_device_path *bootefi_image_path;
  31 static struct efi_device_path *bootefi_device_path;
  32
  33 /**
  34  * efi_env_set_load_options() - set load options from environment variable
  35  *
  36  * @handle:             the image handle
  37  * @env_var:            name of the environment variable
  38  * @load_options:       pointer to load options (output)
  39  * Return:              status code
  40  */
  41 static efi_status_t efi_env_set_load_options(efi_handle_t handle,
  42                                              const char *env_var,
  43                                              u16 **load_options)
  44 {
  45         const char *env = env_get(env_var);
  46         size_t size;
  47         u16 *pos;
  48         efi_status_t ret;
  49
  50         *load_options = NULL;
  51         if (!env)
  52                 return EFI_SUCCESS;
  53         size = sizeof(u16) * (utf8_utf16_strlen(env) + 1);
  54         pos = calloc(size, 1);
  55         if (!pos)
  56                 return EFI_OUT_OF_RESOURCES;
  57         *load_options = pos;
  58         utf8_utf16_strcpy(&pos, env);
  59         ret = efi_set_load_options(handle, size, *load_options);
  60         if (ret != EFI_SUCCESS) {
  61                 free(*load_options);
  62                 *load_options = NULL;
  63         }
  64         return ret;
  65 }
  66
  67 #if !CONFIG_IS_ENABLED(GENERATE_ACPI_TABLE)
  68
  69 /**
  70  * copy_fdt() - Copy the device tree to a new location available to EFI
  71  *
  72  * The FDT is copied to a suitable location within the EFI memory map.
  73  * Additional 12 KiB are added to the space in case the device tree needs to be
  74  * expanded later with fdt_open_into().
  75  *
  76  * @fdtp:       On entry a pointer to the flattened device tree.
  77  *              On exit a pointer to the copy of the flattened device tree.
  78  *              FDT start
  79  * Return:      status code
  80  */
  81 static efi_status_t copy_fdt(void **fdtp)
  82 {
  83         unsigned long fdt_ram_start = -1L, fdt_pages;
  84         efi_status_t ret = 0;
  85         void *fdt, *new_fdt;
  86         u64 new_fdt_addr;
  87         uint fdt_size;
  88         int i;
  89
  90         for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
  91                 u64 ram_start = gd->bd->bi_dram[i].start;
  92                 u64 ram_size = gd->bd->bi_dram[i].size;
  93
  94                 if (!ram_size)
  95                         continue;
  96
  97                 if (ram_start < fdt_ram_start)
  98                         fdt_ram_start = ram_start;
  99         }
 100
 101         /*
 102          * Give us at least 12 KiB of breathing room in case the device tree
 103          * needs to be expanded later.
 104          */
 105         fdt = *fdtp;
 106         fdt_pages = efi_size_in_pages(fdt_totalsize(fdt) + 0x3000);
 107         fdt_size = fdt_pages << EFI_PAGE_SHIFT;
 108
 109         /*
 110          * Safe fdt location is at 127 MiB.
 111          * On the sandbox convert from the sandbox address space.
 112          */
 113         new_fdt_addr = (uintptr_t)map_sysmem(fdt_ram_start + 0x7f00000 +
 114                                              fdt_size, 0);
 115         ret = efi_allocate_pages(EFI_ALLOCATE_MAX_ADDRESS,
 116                                  EFI_ACPI_RECLAIM_MEMORY, fdt_pages,
 117                                  &new_fdt_addr);
 118         if (ret != EFI_SUCCESS) {
 119                 /* If we can't put it there, put it somewhere */
 120                 new_fdt_addr = (ulong)memalign(EFI_PAGE_SIZE, fdt_size);
 121                 ret = efi_allocate_pages(EFI_ALLOCATE_MAX_ADDRESS,
 122                                          EFI_ACPI_RECLAIM_MEMORY, fdt_pages,
 123                                          &new_fdt_addr);
 124                 if (ret != EFI_SUCCESS) {
 125                         log_err("ERROR: Failed to reserve space for FDT\n");
 126                         goto done;
 127                 }
 128         }
 129         new_fdt = (void *)(uintptr_t)new_fdt_addr;
 130         memcpy(new_fdt, fdt, fdt_totalsize(fdt));
 131         fdt_set_totalsize(new_fdt, fdt_size);
 132
 133         *fdtp = (void *)(uintptr_t)new_fdt_addr;
 134 done:
 135         return ret;
 136 }
 137
 138 static void efi_reserve_memory(u64 addr, u64 size)
 139 {
 140         /* Convert from sandbox address space. */
 141         addr = (uintptr_t)map_sysmem(addr, 0);
 142         if (efi_add_memory_map(addr, size,
 143                                EFI_RESERVED_MEMORY_TYPE) != EFI_SUCCESS)
 144                 log_err("Reserved memory mapping failed addr %llx size %llx\n",
 145                         addr, size);
 146 }
 147
 148 /**
 149  * efi_carve_out_dt_rsv() - Carve out DT reserved memory ranges
 150  *
 151  * The mem_rsv entries of the FDT are added to the memory map. Any failures are
 152  * ignored because this is not critical and we would rather continue to try to
 153  * boot.
 154  *
 155  * @fdt: Pointer to device tree
 156  */
 157 static void efi_carve_out_dt_rsv(void *fdt)
 158 {
 159         int nr_rsv, i;
 160         u64 addr, size;
 161         int nodeoffset, subnode;
 162
 163         nr_rsv = fdt_num_mem_rsv(fdt);
 164
 165         /* Look for an existing entry and add it to the efi mem map. */
 166         for (i = 0; i < nr_rsv; i++) {
 167                 if (fdt_get_mem_rsv(fdt, i, &addr, &size) != 0)
 168                         continue;
 169                 efi_reserve_memory(addr, size);
 170         }
 171
 172         /* process reserved-memory */
 173         nodeoffset = fdt_subnode_offset(fdt, 0, "reserved-memory");
 174         if (nodeoffset >= 0) {
 175                 subnode = fdt_first_subnode(fdt, nodeoffset);
 176                 while (subnode >= 0) {
 177                         fdt_addr_t fdt_addr;
 178                         fdt_size_t fdt_size;
 179
 180                         /* check if this subnode has a reg property */
 181                         fdt_addr = fdtdec_get_addr_size_auto_parent(
 182                                                 fdt, nodeoffset, subnode,
 183                                                 "reg", 0, &fdt_size, false);
 184                         /*
 185                          * The /reserved-memory node may have children with
 186                          * a size instead of a reg property.
 187                          */
 188                         if (fdt_addr != FDT_ADDR_T_NONE &&
 189                             fdtdec_get_is_enabled(fdt, subnode))
 190                                 efi_reserve_memory(fdt_addr, fdt_size);
 191                         subnode = fdt_next_subnode(fdt, subnode);
 192                 }
 193         }
 194 }
 195
 196 /**
 197  * get_config_table() - get configuration table
 198  *
 199  * @guid:       GUID of the configuration table
 200  * Return:      pointer to configuration table or NULL
 201  */
 202 static void *get_config_table(const efi_guid_t *guid)
 203 {
 204         size_t i;
 205
 206         for (i = 0; i < systab.nr_tables; i++) {
 207                 if (!guidcmp(guid, &systab.tables[i].guid))
 208                         return systab.tables[i].table;
 209         }
 210         return NULL;
 211 }
 212
 213 #endif /* !CONFIG_IS_ENABLED(GENERATE_ACPI_TABLE) */
 214
 215 /**
 216  * efi_install_fdt() - install device tree
 217  *
 218  * If fdt is not EFI_FDT_USE_INTERNAL, the device tree located at that memory
 219  * address will will be installed as configuration table, otherwise the device
 220  * tree located at the address indicated by environment variable fdt_addr or as
 221  * fallback fdtcontroladdr will be used.
 222  *
 223  * On architectures using ACPI tables device trees shall not be installed as
 224  * configuration table.
 225  *
 226  * @fdt:        address of device tree or EFI_FDT_USE_INTERNAL to use the
 227  *              the hardware device tree as indicated by environment variable
 228  *              fdt_addr or as fallback the internal device tree as indicated by
 229  *              the environment variable fdtcontroladdr
 230  * Return:      status code
 231  */
 232 efi_status_t efi_install_fdt(void *fdt)
 233 {
 234         /*
 235          * The EBBR spec requires that we have either an FDT or an ACPI table
 236          * but not both.
 237          */
 238 #if CONFIG_IS_ENABLED(GENERATE_ACPI_TABLE)
 239         if (fdt) {
 240                 log_err("ERROR: can't have ACPI table and device tree.\n");
 241                 return EFI_LOAD_ERROR;
 242         }
 243 #else
 244         bootm_headers_t img = { 0 };
 245         efi_status_t ret;
 246
 247         if (fdt == EFI_FDT_USE_INTERNAL) {
 248                 const char *fdt_opt;
 249                 uintptr_t fdt_addr;
 250
 251                 /* Look for device tree that is already installed */
 252                 if (get_config_table(&efi_guid_fdt))
 253                         return EFI_SUCCESS;
 254                 /* Check if there is a hardware device tree */
 255                 fdt_opt = env_get("fdt_addr");
 256                 /* Use our own device tree as fallback */
 257                 if (!fdt_opt) {
 258                         fdt_opt = env_get("fdtcontroladdr");
 259                         if (!fdt_opt) {
 260                                 log_err("ERROR: need device tree\n");
 261                                 return EFI_NOT_FOUND;
 262                         }
 263                 }
 264                 fdt_addr = simple_strtoul(fdt_opt, NULL, 16);
 265                 if (!fdt_addr) {
 266                         log_err("ERROR: invalid $fdt_addr or $fdtcontroladdr\n");
 267                         return EFI_LOAD_ERROR;
 268                 }
 269                 fdt = map_sysmem(fdt_addr, 0);
 270         }
 271
 272         /* Install device tree */
 273         if (fdt_check_header(fdt)) {
 274                 log_err("ERROR: invalid device tree\n");
 275                 return EFI_LOAD_ERROR;
 276         }
 277
 278         /* Prepare device tree for payload */
 279         ret = copy_fdt(&fdt);
 280         if (ret) {
 281                 log_err("ERROR: out of memory\n");
 282                 return EFI_OUT_OF_RESOURCES;
 283         }
 284
 285         if (image_setup_libfdt(&img, fdt, 0, NULL)) {
 286                 log_err("ERROR: failed to process device tree\n");
 287                 return EFI_LOAD_ERROR;
 288         }
 289
 290         /* Create memory reservations as indicated by the device tree */
 291         efi_carve_out_dt_rsv(fdt);
 292
 293         /* Install device tree as UEFI table */
 294         ret = efi_install_configuration_table(&efi_guid_fdt, fdt);
 295         if (ret != EFI_SUCCESS) {
 296                 log_err("ERROR: failed to install device tree\n");
 297                 return ret;
 298         }
 299 #endif /* GENERATE_ACPI_TABLE */
 300
 301         return EFI_SUCCESS;
 302 }
 303
 304 /**
 305  * do_bootefi_exec() - execute EFI binary
 306  *
 307  * @handle:             handle of loaded image
 308  * Return:              status code
 309  *
 310  * Load the EFI binary into a newly assigned memory unwinding the relocation
 311  * information, install the loaded image protocol, and call the binary.
 312  */
 313 static efi_status_t do_bootefi_exec(efi_handle_t handle, void *load_options)
 314 {
 315         efi_status_t ret;
 316         efi_uintn_t exit_data_size = 0;
 317         u16 *exit_data = NULL;
 318
 319         /* Call our payload! */
 320         ret = EFI_CALL(efi_start_image(handle, &exit_data_size, &exit_data));
 321         if (ret != EFI_SUCCESS) {
 322                 log_err("## Application failed, r = %lu\n",
 323                         ret & ~EFI_ERROR_MASK);
 324                 if (exit_data) {
 325                         log_err("## %ls\n", exit_data);
 326                         efi_free_pool(exit_data);
 327                 }
 328         }
 329
 330         efi_restore_gd();
 331
 332         free(load_options);
 333
 334         return ret;
 335 }
 336
 337 /**
 338  * do_efibootmgr() - execute EFI boot manager
 339  *
 340  * Return:      status code
 341  */
 342 static int do_efibootmgr(void)
 343 {
 344         efi_handle_t handle;
 345         efi_status_t ret;
 346         void *load_options;
 347
 348         ret = efi_bootmgr_load(&handle, &load_options);
 349         if (ret != EFI_SUCCESS) {
 350                 log_notice("EFI boot manager: Cannot load any image\n");
 351                 return CMD_RET_FAILURE;
 352         }
 353
 354         ret = do_bootefi_exec(handle, load_options);
 355
 356         if (ret != EFI_SUCCESS)
 357                 return CMD_RET_FAILURE;
 358
 359         return CMD_RET_SUCCESS;
 360 }
 361
 362 /**
 363  * do_bootefi_image() - execute EFI binary
 364  *
 365  * Set up memory image for the binary to be loaded, prepare device path, and
 366  * then call do_bootefi_exec() to execute it.
 367  *
 368  * @image_opt:  string of image start address
 369  * Return:      status code
 370  */
 371 static int do_bootefi_image(const char *image_opt)
 372 {
 373         void *image_buf;
 374         unsigned long addr, size;
 375         const char *size_str;
 376         efi_status_t ret;
 377
 378 #ifdef CONFIG_CMD_BOOTEFI_HELLO
 379         if (!strcmp(image_opt, "hello")) {
 380                 char *saddr;
 381
 382                 saddr = env_get("loadaddr");
 383                 size = __efi_helloworld_end - __efi_helloworld_begin;
 384
 385                 if (saddr)
 386                         addr = simple_strtoul(saddr, NULL, 16);
 387                 else
 388                         addr = CONFIG_SYS_LOAD_ADDR;
 389
 390                 image_buf = map_sysmem(addr, size);
 391                 memcpy(image_buf, __efi_helloworld_begin, size);
 392
 393                 efi_free_pool(bootefi_device_path);
 394                 efi_free_pool(bootefi_image_path);
 395                 bootefi_device_path = NULL;
 396                 bootefi_image_path = NULL;
 397         } else
 398 #endif
 399         {
 400                 size_str = env_get("filesize");
 401                 if (size_str)
 402                         size = simple_strtoul(size_str, NULL, 16);
 403                 else
 404                         size = 0;
 405
 406                 addr = simple_strtoul(image_opt, NULL, 16);
 407                 /* Check that a numeric value was passed */
 408                 if (!addr && *image_opt != '0')
 409                         return CMD_RET_USAGE;
 410
 411                 image_buf = map_sysmem(addr, size);
 412         }
 413         ret = efi_run_image(image_buf, size);
 414
 415         if (ret != EFI_SUCCESS)
 416                 return CMD_RET_FAILURE;
 417
 418         return CMD_RET_SUCCESS;
 419 }
 420
 421 /**
 422  * efi_run_image() - run loaded UEFI image
 423  *
 424  * @source_buffer:      memory address of the UEFI image
 425  * @source_size:        size of the UEFI image
 426  * Return:              status code
 427  */
 428 efi_status_t efi_run_image(void *source_buffer, efi_uintn_t source_size)
 429 {
 430         efi_handle_t mem_handle = NULL, handle;
 431         struct efi_device_path *file_path = NULL;
 432         efi_status_t ret;
 433
 434         if (!bootefi_device_path || !bootefi_image_path) {
 435                 /*
 436                  * Special case for efi payload not loaded from disk,
 437                  * such as 'bootefi hello' or for example payload
 438                  * loaded directly into memory via JTAG, etc:
 439                  */
 440                 file_path = efi_dp_from_mem(EFI_RESERVED_MEMORY_TYPE,
 441                                             (uintptr_t)source_buffer,
 442                                             source_size);
 443                 /*
 444                  * Make sure that device for device_path exist
 445                  * in load_image(). Otherwise, shell and grub will fail.
 446                  */
 447                 ret = efi_create_handle(&mem_handle);
 448                 if (ret != EFI_SUCCESS)
 449                         goto out;
 450
 451                 ret = efi_add_protocol(mem_handle, &efi_guid_device_path,
 452                                        file_path);
 453                 if (ret != EFI_SUCCESS)
 454                         goto out;
 455         } else {
 456                 file_path = efi_dp_append(bootefi_device_path,
 457                                           bootefi_image_path);
 458         }
 459
 460         ret = EFI_CALL(efi_load_image(false, efi_root, file_path, source_buffer,
 461                                       source_size, &handle));
 462         if (ret != EFI_SUCCESS)
 463                 goto out;
 464
 465         u16 *load_options;
 466
 467         /* Transfer environment variable as load options */
 468         ret = efi_env_set_load_options(handle, "bootargs", &load_options);
 469         if (ret != EFI_SUCCESS)
 470                 goto out;
 471
 472         ret = do_bootefi_exec(handle, load_options);
 473
 474 out:
 475         efi_delete_handle(mem_handle);
 476         efi_free_pool(file_path);
 477         return ret;
 478 }
 479
 480 #ifdef CONFIG_CMD_BOOTEFI_SELFTEST
 481 static efi_status_t bootefi_run_prepare(const char *load_options_path,
 482                 struct efi_device_path *device_path,
 483                 struct efi_device_path *image_path,
 484                 struct efi_loaded_image_obj **image_objp,
 485                 struct efi_loaded_image **loaded_image_infop)
 486 {
 487         efi_status_t ret;
 488         u16 *load_options;
 489
 490         ret = efi_setup_loaded_image(device_path, image_path, image_objp,
 491                                      loaded_image_infop);
 492         if (ret != EFI_SUCCESS)
 493                 return ret;
 494
 495         /* Transfer environment variable as load options */
 496         return efi_env_set_load_options((efi_handle_t)*image_objp,
 497                                         load_options_path,
 498                                         &load_options);
 499 }
 500
 501 /**
 502  * bootefi_test_prepare() - prepare to run an EFI test
 503  *
 504  * Prepare to run a test as if it were provided by a loaded image.
 505  *
 506  * @image_objp:         pointer to be set to the loaded image handle
 507  * @loaded_image_infop: pointer to be set to the loaded image protocol
 508  * @path:               dummy file path used to construct the device path
 509  *                      set in the loaded image protocol
 510  * @load_options_path:  name of a U-Boot environment variable. Its value is
 511  *                      set as load options in the loaded image protocol.
 512  * Return:              status code
 513  */
 514 static efi_status_t bootefi_test_prepare
 515                 (struct efi_loaded_image_obj **image_objp,
 516                  struct efi_loaded_image **loaded_image_infop, const char *path,
 517                  const char *load_options_path)
 518 {
 519         efi_status_t ret;
 520
 521         /* Construct a dummy device path */
 522         bootefi_device_path = efi_dp_from_mem(EFI_RESERVED_MEMORY_TYPE, 0, 0);
 523         if (!bootefi_device_path)
 524                 return EFI_OUT_OF_RESOURCES;
 525
 526         bootefi_image_path = efi_dp_from_file(NULL, 0, path);
 527         if (!bootefi_image_path) {
 528                 ret = EFI_OUT_OF_RESOURCES;
 529                 goto failure;
 530         }
 531
 532         ret = bootefi_run_prepare(load_options_path, bootefi_device_path,
 533                                   bootefi_image_path, image_objp,
 534                                   loaded_image_infop);
 535         if (ret == EFI_SUCCESS)
 536                 return ret;
 537
 538         efi_free_pool(bootefi_image_path);
 539         bootefi_image_path = NULL;
 540 failure:
 541         efi_free_pool(bootefi_device_path);
 542         bootefi_device_path = NULL;
 543         return ret;
 544 }
 545
 546 /**
 547  * bootefi_run_finish() - finish up after running an EFI test
 548  *
 549  * @loaded_image_info: Pointer to a struct which holds the loaded image info
 550  * @image_obj: Pointer to a struct which holds the loaded image object
 551  */
 552 static void bootefi_run_finish(struct efi_loaded_image_obj *image_obj,
 553                                struct efi_loaded_image *loaded_image_info)
 554 {
 555         efi_restore_gd();
 556         free(loaded_image_info->load_options);
 557         efi_delete_handle(&image_obj->header);
 558 }
 559
 560 /**
 561  * do_efi_selftest() - execute EFI selftest
 562  *
 563  * Return:      status code
 564  */
 565 static int do_efi_selftest(void)
 566 {
 567         struct efi_loaded_image_obj *image_obj;
 568         struct efi_loaded_image *loaded_image_info;
 569         efi_status_t ret;
 570
 571         ret = bootefi_test_prepare(&image_obj, &loaded_image_info,
 572                                    "\\selftest", "efi_selftest");
 573         if (ret != EFI_SUCCESS)
 574                 return CMD_RET_FAILURE;
 575
 576         /* Execute the test */
 577         ret = EFI_CALL(efi_selftest(&image_obj->header, &systab));
 578         bootefi_run_finish(image_obj, loaded_image_info);
 579
 580         return ret != EFI_SUCCESS;
 581 }
 582 #endif /* CONFIG_CMD_BOOTEFI_SELFTEST */
 583
 584 /**
 585  * do_bootefi() - execute `bootefi` command
 586  *
 587  * @cmdtp:      table entry describing command
 588  * @flag:       bitmap indicating how the command was invoked
 589  * @argc:       number of arguments
 590  * @argv:       command line arguments
 591  * Return:      status code
 592  */
 593 static int do_bootefi(struct cmd_tbl *cmdtp, int flag, int argc,
 594                       char *const argv[])
 595 {
 596         efi_status_t ret;
 597         void *fdt;
 598
 599         if (argc < 2)
 600                 return CMD_RET_USAGE;
 601
 602         /* Initialize EFI drivers */
 603         ret = efi_init_obj_list();
 604         if (ret != EFI_SUCCESS) {
 605                 log_err("Error: Cannot initialize UEFI sub-system, r = %lu\n",
 606                         ret & ~EFI_ERROR_MASK);
 607                 return CMD_RET_FAILURE;
 608         }
 609
 610         if (argc > 2) {
 611                 uintptr_t fdt_addr;
 612
 613                 fdt_addr = simple_strtoul(argv[2], NULL, 16);
 614                 fdt = map_sysmem(fdt_addr, 0);
 615         } else {
 616                 fdt = EFI_FDT_USE_INTERNAL;
 617         }
 618         ret = efi_install_fdt(fdt);
 619         if (ret == EFI_INVALID_PARAMETER)
 620                 return CMD_RET_USAGE;
 621         else if (ret != EFI_SUCCESS)
 622                 return CMD_RET_FAILURE;
 623
 624         if (!strcmp(argv[1], "bootmgr"))
 625                 return do_efibootmgr();
 626 #ifdef CONFIG_CMD_BOOTEFI_SELFTEST
 627         else if (!strcmp(argv[1], "selftest"))
 628                 return do_efi_selftest();
 629 #endif
 630
 631         return do_bootefi_image(argv[1]);
 632 }
 633
 634 #ifdef CONFIG_SYS_LONGHELP
 635 static char bootefi_help_text[] =
 636         "<image address> [fdt address]\n"
 637         "  - boot EFI payload stored at address <image address>.\n"
 638         "    If specified, the device tree located at <fdt address> gets\n"
 639         "    exposed as EFI configuration table.\n"
 640 #ifdef CONFIG_CMD_BOOTEFI_HELLO
 641         "bootefi hello\n"
 642         "  - boot a sample Hello World application stored within U-Boot\n"
 643 #endif
 644 #ifdef CONFIG_CMD_BOOTEFI_SELFTEST
 645         "bootefi selftest [fdt address]\n"
 646         "  - boot an EFI selftest application stored within U-Boot\n"
 647         "    Use environment variable efi_selftest to select a single test.\n"
 648         "    Use 'setenv efi_selftest list' to enumerate all tests.\n"
 649 #endif
 650         "bootefi bootmgr [fdt address]\n"
 651         "  - load and boot EFI payload based on BootOrder/BootXXXX variables.\n"
 652         "\n"
 653         "    If specified, the device tree located at <fdt address> gets\n"
 654         "    exposed as EFI configuration table.\n";
 655 #endif
 656
 657 U_BOOT_CMD(
 658         bootefi, 3, 0, do_bootefi,
 659         "Boots an EFI payload from memory",
 660         bootefi_help_text
 661 );
 662
 663 /**
 664  * efi_set_bootdev() - set boot device
 665  *
 666  * This function is called when a file is loaded, e.g. via the 'load' command.
 667  * We use the path to this file to inform the UEFI binary about the boot device.
 668  *
 669  * @dev:        device, e.g. "MMC"
 670  * @devnr:      number of the device, e.g. "1:2"
 671  * @path:       path to file loaded
 672  */
 673 void efi_set_bootdev(const char *dev, const char *devnr, const char *path)
 674 {
 675         struct efi_device_path *device, *image;
 676         efi_status_t ret;
 677
 678         /* efi_set_bootdev is typically called repeatedly, recover memory */
 679         efi_free_pool(bootefi_device_path);
 680         efi_free_pool(bootefi_image_path);
 681
 682         ret = efi_dp_from_name(dev, devnr, path, &device, &image);
 683         if (ret == EFI_SUCCESS) {
 684                 bootefi_device_path = device;
 685                 if (image) {
 686                         /* FIXME: image should not contain device */
 687                         struct efi_device_path *image_tmp = image;
 688
 689                         efi_dp_split_file_path(image, &device, &image);
 690                         efi_free_pool(image_tmp);
 691                 }
 692                 bootefi_image_path = image;
 693         } else {
 694                 bootefi_device_path = NULL;
 695                 bootefi_image_path = NULL;
 696         }
 697 }