uboot/cmd/bootefi.c
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   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 <bootm.h>
  12#include <charset.h>
  13#include <command.h>
  14#include <dm.h>
  15#include <efi_loader.h>
  16#include <efi_selftest.h>
  17#include <env.h>
  18#include <errno.h>
  19#include <image.h>
  20#include <log.h>
  21#include <malloc.h>
  22#include <asm/global_data.h>
  23#include <linux/libfdt.h>
  24#include <linux/libfdt_env.h>
  25#include <mapmem.h>
  26#include <memalign.h>
  27#include <asm-generic/sections.h>
  28#include <linux/linkage.h>
  29
  30DECLARE_GLOBAL_DATA_PTR;
  31
  32static struct efi_device_path *bootefi_image_path;
  33static struct efi_device_path *bootefi_device_path;
  34static void *image_addr;
  35static size_t image_size;
  36
  37/**
  38 * efi_clear_bootdev() - clear boot device
  39 */
  40static void efi_clear_bootdev(void)
  41{
  42        efi_free_pool(bootefi_device_path);
  43        efi_free_pool(bootefi_image_path);
  44        bootefi_device_path = NULL;
  45        bootefi_image_path = NULL;
  46        image_addr = NULL;
  47        image_size = 0;
  48}
  49
  50/**
  51 * efi_set_bootdev() - set boot device
  52 *
  53 * This function is called when a file is loaded, e.g. via the 'load' command.
  54 * We use the path to this file to inform the UEFI binary about the boot device.
  55 *
  56 * @dev:                device, e.g. "MMC"
  57 * @devnr:              number of the device, e.g. "1:2"
  58 * @path:               path to file loaded
  59 * @buffer:             buffer with file loaded
  60 * @buffer_size:        size of file loaded
  61 */
  62void efi_set_bootdev(const char *dev, const char *devnr, const char *path,
  63                     void *buffer, size_t buffer_size)
  64{
  65        struct efi_device_path *device, *image;
  66        efi_status_t ret;
  67
  68        /* Forget overwritten image */
  69        if (buffer + buffer_size >= image_addr &&
  70            image_addr + image_size >= buffer)
  71                efi_clear_bootdev();
  72
  73        /* Remember only PE-COFF and FIT images */
  74        if (efi_check_pe(buffer, buffer_size, NULL) != EFI_SUCCESS) {
  75#ifdef CONFIG_FIT
  76                if (fit_check_format(buffer, IMAGE_SIZE_INVAL))
  77                        return;
  78                /*
  79                 * FIT images of type EFI_OS are started via command bootm.
  80                 * We should not use their boot device with the bootefi command.
  81                 */
  82                buffer = 0;
  83                buffer_size = 0;
  84#else
  85                return;
  86#endif
  87        }
  88
  89        /* efi_set_bootdev() is typically called repeatedly, recover memory */
  90        efi_clear_bootdev();
  91
  92        image_addr = buffer;
  93        image_size = buffer_size;
  94
  95        ret = efi_dp_from_name(dev, devnr, path, &device, &image);
  96        if (ret == EFI_SUCCESS) {
  97                bootefi_device_path = device;
  98                if (image) {
  99                        /* FIXME: image should not contain device */
 100                        struct efi_device_path *image_tmp = image;
 101
 102                        efi_dp_split_file_path(image, &device, &image);
 103                        efi_free_pool(image_tmp);
 104                }
 105                bootefi_image_path = image;
 106        } else {
 107                efi_clear_bootdev();
 108        }
 109}
 110
 111/**
 112 * efi_env_set_load_options() - set load options from environment variable
 113 *
 114 * @handle:             the image handle
 115 * @env_var:            name of the environment variable
 116 * @load_options:       pointer to load options (output)
 117 * Return:              status code
 118 */
 119static efi_status_t efi_env_set_load_options(efi_handle_t handle,
 120                                             const char *env_var,
 121                                             u16 **load_options)
 122{
 123        const char *env = env_get(env_var);
 124        size_t size;
 125        u16 *pos;
 126        efi_status_t ret;
 127
 128        *load_options = NULL;
 129        if (!env)
 130                return EFI_SUCCESS;
 131        size = sizeof(u16) * (utf8_utf16_strlen(env) + 1);
 132        pos = calloc(size, 1);
 133        if (!pos)
 134                return EFI_OUT_OF_RESOURCES;
 135        *load_options = pos;
 136        utf8_utf16_strcpy(&pos, env);
 137        ret = efi_set_load_options(handle, size, *load_options);
 138        if (ret != EFI_SUCCESS) {
 139                free(*load_options);
 140                *load_options = NULL;
 141        }
 142        return ret;
 143}
 144
 145#if !CONFIG_IS_ENABLED(GENERATE_ACPI_TABLE)
 146
 147/**
 148 * copy_fdt() - Copy the device tree to a new location available to EFI
 149 *
 150 * The FDT is copied to a suitable location within the EFI memory map.
 151 * Additional 12 KiB are added to the space in case the device tree needs to be
 152 * expanded later with fdt_open_into().
 153 *
 154 * @fdtp:       On entry a pointer to the flattened device tree.
 155 *              On exit a pointer to the copy of the flattened device tree.
 156 *              FDT start
 157 * Return:      status code
 158 */
 159static efi_status_t copy_fdt(void **fdtp)
 160{
 161        unsigned long fdt_ram_start = -1L, fdt_pages;
 162        efi_status_t ret = 0;
 163        void *fdt, *new_fdt;
 164        u64 new_fdt_addr;
 165        uint fdt_size;
 166        int i;
 167
 168        for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
 169                u64 ram_start = gd->bd->bi_dram[i].start;
 170                u64 ram_size = gd->bd->bi_dram[i].size;
 171
 172                if (!ram_size)
 173                        continue;
 174
 175                if (ram_start < fdt_ram_start)
 176                        fdt_ram_start = ram_start;
 177        }
 178
 179        /*
 180         * Give us at least 12 KiB of breathing room in case the device tree
 181         * needs to be expanded later.
 182         */
 183        fdt = *fdtp;
 184        fdt_pages = efi_size_in_pages(fdt_totalsize(fdt) + 0x3000);
 185        fdt_size = fdt_pages << EFI_PAGE_SHIFT;
 186
 187        /*
 188         * Safe fdt location is at 127 MiB.
 189         * On the sandbox convert from the sandbox address space.
 190         */
 191        new_fdt_addr = (uintptr_t)map_sysmem(fdt_ram_start + 0x7f00000 +
 192                                             fdt_size, 0);
 193        ret = efi_allocate_pages(EFI_ALLOCATE_MAX_ADDRESS,
 194                                 EFI_ACPI_RECLAIM_MEMORY, fdt_pages,
 195                                 &new_fdt_addr);
 196        if (ret != EFI_SUCCESS) {
 197                /* If we can't put it there, put it somewhere */
 198                new_fdt_addr = (ulong)memalign(EFI_PAGE_SIZE, fdt_size);
 199                ret = efi_allocate_pages(EFI_ALLOCATE_MAX_ADDRESS,
 200                                         EFI_ACPI_RECLAIM_MEMORY, fdt_pages,
 201                                         &new_fdt_addr);
 202                if (ret != EFI_SUCCESS) {
 203                        log_err("ERROR: Failed to reserve space for FDT\n");
 204                        goto done;
 205                }
 206        }
 207        new_fdt = (void *)(uintptr_t)new_fdt_addr;
 208        memcpy(new_fdt, fdt, fdt_totalsize(fdt));
 209        fdt_set_totalsize(new_fdt, fdt_size);
 210
 211        *fdtp = (void *)(uintptr_t)new_fdt_addr;
 212done:
 213        return ret;
 214}
 215
 216/**
 217 * get_config_table() - get configuration table
 218 *
 219 * @guid:       GUID of the configuration table
 220 * Return:      pointer to configuration table or NULL
 221 */
 222static void *get_config_table(const efi_guid_t *guid)
 223{
 224        size_t i;
 225
 226        for (i = 0; i < systab.nr_tables; i++) {
 227                if (!guidcmp(guid, &systab.tables[i].guid))
 228                        return systab.tables[i].table;
 229        }
 230        return NULL;
 231}
 232
 233#endif /* !CONFIG_IS_ENABLED(GENERATE_ACPI_TABLE) */
 234
 235/**
 236 * efi_install_fdt() - install device tree
 237 *
 238 * If fdt is not EFI_FDT_USE_INTERNAL, the device tree located at that memory
 239 * address will will be installed as configuration table, otherwise the device
 240 * tree located at the address indicated by environment variable fdt_addr or as
 241 * fallback fdtcontroladdr will be used.
 242 *
 243 * On architectures using ACPI tables device trees shall not be installed as
 244 * configuration table.
 245 *
 246 * @fdt:        address of device tree or EFI_FDT_USE_INTERNAL to use the
 247 *              the hardware device tree as indicated by environment variable
 248 *              fdt_addr or as fallback the internal device tree as indicated by
 249 *              the environment variable fdtcontroladdr
 250 * Return:      status code
 251 */
 252efi_status_t efi_install_fdt(void *fdt)
 253{
 254        /*
 255         * The EBBR spec requires that we have either an FDT or an ACPI table
 256         * but not both.
 257         */
 258#if CONFIG_IS_ENABLED(GENERATE_ACPI_TABLE)
 259        if (fdt) {
 260                log_err("ERROR: can't have ACPI table and device tree.\n");
 261                return EFI_LOAD_ERROR;
 262        }
 263#else
 264        bootm_headers_t img = { 0 };
 265        efi_status_t ret;
 266
 267        if (fdt == EFI_FDT_USE_INTERNAL) {
 268                const char *fdt_opt;
 269                uintptr_t fdt_addr;
 270
 271                /* Look for device tree that is already installed */
 272                if (get_config_table(&efi_guid_fdt))
 273                        return EFI_SUCCESS;
 274                /* Check if there is a hardware device tree */
 275                fdt_opt = env_get("fdt_addr");
 276                /* Use our own device tree as fallback */
 277                if (!fdt_opt) {
 278                        fdt_opt = env_get("fdtcontroladdr");
 279                        if (!fdt_opt) {
 280                                log_err("ERROR: need device tree\n");
 281                                return EFI_NOT_FOUND;
 282                        }
 283                }
 284                fdt_addr = simple_strtoul(fdt_opt, NULL, 16);
 285                if (!fdt_addr) {
 286                        log_err("ERROR: invalid $fdt_addr or $fdtcontroladdr\n");
 287                        return EFI_LOAD_ERROR;
 288                }
 289                fdt = map_sysmem(fdt_addr, 0);
 290        }
 291
 292        /* Install device tree */
 293        if (fdt_check_header(fdt)) {
 294                log_err("ERROR: invalid device tree\n");
 295                return EFI_LOAD_ERROR;
 296        }
 297
 298        /* Prepare device tree for payload */
 299        ret = copy_fdt(&fdt);
 300        if (ret) {
 301                log_err("ERROR: out of memory\n");
 302                return EFI_OUT_OF_RESOURCES;
 303        }
 304
 305        if (image_setup_libfdt(&img, fdt, 0, NULL)) {
 306                log_err("ERROR: failed to process device tree\n");
 307                return EFI_LOAD_ERROR;
 308        }
 309
 310        /* Create memory reservations as indicated by the device tree */
 311        efi_carve_out_dt_rsv(fdt);
 312
 313        /* Install device tree as UEFI table */
 314        ret = efi_install_configuration_table(&efi_guid_fdt, fdt);
 315        if (ret != EFI_SUCCESS) {
 316                log_err("ERROR: failed to install device tree\n");
 317                return ret;
 318        }
 319#endif /* GENERATE_ACPI_TABLE */
 320
 321        return EFI_SUCCESS;
 322}
 323
 324/**
 325 * do_bootefi_exec() - execute EFI binary
 326 *
 327 * The image indicated by @handle is started. When it returns the allocated
 328 * memory for the @load_options is freed.
 329 *
 330 * @handle:             handle of loaded image
 331 * @load_options:       load options
 332 * Return:              status code
 333 *
 334 * Load the EFI binary into a newly assigned memory unwinding the relocation
 335 * information, install the loaded image protocol, and call the binary.
 336 */
 337static efi_status_t do_bootefi_exec(efi_handle_t handle, void *load_options)
 338{
 339        efi_status_t ret;
 340        efi_uintn_t exit_data_size = 0;
 341        u16 *exit_data = NULL;
 342
 343        /* On ARM switch from EL3 or secure mode to EL2 or non-secure mode */
 344        switch_to_non_secure_mode();
 345
 346        /* Call our payload! */
 347        ret = EFI_CALL(efi_start_image(handle, &exit_data_size, &exit_data));
 348        if (ret != EFI_SUCCESS) {
 349                log_err("## Application failed, r = %lu\n",
 350                        ret & ~EFI_ERROR_MASK);
 351                if (exit_data) {
 352                        log_err("## %ls\n", exit_data);
 353                        efi_free_pool(exit_data);
 354                }
 355        }
 356
 357        efi_restore_gd();
 358
 359        free(load_options);
 360
 361        if (IS_ENABLED(CONFIG_EFI_LOAD_FILE2_INITRD))
 362                efi_initrd_deregister();
 363
 364        return ret;
 365}
 366
 367/**
 368 * do_efibootmgr() - execute EFI boot manager
 369 *
 370 * Return:      status code
 371 */
 372static int do_efibootmgr(void)
 373{
 374        efi_handle_t handle;
 375        efi_status_t ret;
 376        void *load_options;
 377
 378        ret = efi_bootmgr_load(&handle, &load_options);
 379        if (ret != EFI_SUCCESS) {
 380                log_notice("EFI boot manager: Cannot load any image\n");
 381                return CMD_RET_FAILURE;
 382        }
 383
 384        ret = do_bootefi_exec(handle, load_options);
 385
 386        if (ret != EFI_SUCCESS)
 387                return CMD_RET_FAILURE;
 388
 389        return CMD_RET_SUCCESS;
 390}
 391
 392/**
 393 * do_bootefi_image() - execute EFI binary
 394 *
 395 * Set up memory image for the binary to be loaded, prepare device path, and
 396 * then call do_bootefi_exec() to execute it.
 397 *
 398 * @image_opt:  string of image start address
 399 * Return:      status code
 400 */
 401static int do_bootefi_image(const char *image_opt)
 402{
 403        void *image_buf;
 404        unsigned long addr, size;
 405        efi_status_t ret;
 406
 407#ifdef CONFIG_CMD_BOOTEFI_HELLO
 408        if (!strcmp(image_opt, "hello")) {
 409                image_buf = __efi_helloworld_begin;
 410                size = __efi_helloworld_end - __efi_helloworld_begin;
 411                efi_clear_bootdev();
 412        } else
 413#endif
 414        {
 415                addr = strtoul(image_opt, NULL, 16);
 416                /* Check that a numeric value was passed */
 417                if (!addr)
 418                        return CMD_RET_USAGE;
 419
 420                image_buf = map_sysmem(addr, 0);
 421
 422                if (image_buf != image_addr) {
 423                        log_err("No UEFI binary known at %s\n", image_opt);
 424                        return CMD_RET_FAILURE;
 425                }
 426                size = image_size;
 427        }
 428        ret = efi_run_image(image_buf, size);
 429
 430        if (ret != EFI_SUCCESS)
 431                return CMD_RET_FAILURE;
 432
 433        return CMD_RET_SUCCESS;
 434}
 435
 436/**
 437 * efi_run_image() - run loaded UEFI image
 438 *
 439 * @source_buffer:      memory address of the UEFI image
 440 * @source_size:        size of the UEFI image
 441 * Return:              status code
 442 */
 443efi_status_t efi_run_image(void *source_buffer, efi_uintn_t source_size)
 444{
 445        efi_handle_t mem_handle = NULL, handle;
 446        struct efi_device_path *file_path = NULL;
 447        struct efi_device_path *msg_path;
 448        efi_status_t ret;
 449        u16 *load_options;
 450
 451        if (!bootefi_device_path || !bootefi_image_path) {
 452                /*
 453                 * Special case for efi payload not loaded from disk,
 454                 * such as 'bootefi hello' or for example payload
 455                 * loaded directly into memory via JTAG, etc:
 456                 */
 457                file_path = efi_dp_from_mem(EFI_RESERVED_MEMORY_TYPE,
 458                                            (uintptr_t)source_buffer,
 459                                            source_size);
 460                /*
 461                 * Make sure that device for device_path exist
 462                 * in load_image(). Otherwise, shell and grub will fail.
 463                 */
 464                ret = efi_create_handle(&mem_handle);
 465                if (ret != EFI_SUCCESS)
 466                        goto out;
 467
 468                ret = efi_add_protocol(mem_handle, &efi_guid_device_path,
 469                                       file_path);
 470                if (ret != EFI_SUCCESS)
 471                        goto out;
 472                msg_path = file_path;
 473        } else {
 474                file_path = efi_dp_append(bootefi_device_path,
 475                                          bootefi_image_path);
 476                msg_path = bootefi_image_path;
 477        }
 478
 479        log_info("Booting %pD\n", msg_path);
 480
 481        ret = EFI_CALL(efi_load_image(false, efi_root, file_path, source_buffer,
 482                                      source_size, &handle));
 483        if (ret != EFI_SUCCESS) {
 484                log_err("Loading image failed\n");
 485                goto out;
 486        }
 487
 488        /* Transfer environment variable as load options */
 489        ret = efi_env_set_load_options(handle, "bootargs", &load_options);
 490        if (ret != EFI_SUCCESS)
 491                goto out;
 492
 493        ret = do_bootefi_exec(handle, load_options);
 494
 495out:
 496        efi_delete_handle(mem_handle);
 497        efi_free_pool(file_path);
 498        return ret;
 499}
 500
 501#ifdef CONFIG_CMD_BOOTEFI_SELFTEST
 502static efi_status_t bootefi_run_prepare(const char *load_options_path,
 503                struct efi_device_path *device_path,
 504                struct efi_device_path *image_path,
 505                struct efi_loaded_image_obj **image_objp,
 506                struct efi_loaded_image **loaded_image_infop)
 507{
 508        efi_status_t ret;
 509        u16 *load_options;
 510
 511        ret = efi_setup_loaded_image(device_path, image_path, image_objp,
 512                                     loaded_image_infop);
 513        if (ret != EFI_SUCCESS)
 514                return ret;
 515
 516        /* Transfer environment variable as load options */
 517        return efi_env_set_load_options((efi_handle_t)*image_objp,
 518                                        load_options_path,
 519                                        &load_options);
 520}
 521
 522/**
 523 * bootefi_test_prepare() - prepare to run an EFI test
 524 *
 525 * Prepare to run a test as if it were provided by a loaded image.
 526 *
 527 * @image_objp:         pointer to be set to the loaded image handle
 528 * @loaded_image_infop: pointer to be set to the loaded image protocol
 529 * @path:               dummy file path used to construct the device path
 530 *                      set in the loaded image protocol
 531 * @load_options_path:  name of a U-Boot environment variable. Its value is
 532 *                      set as load options in the loaded image protocol.
 533 * Return:              status code
 534 */
 535static efi_status_t bootefi_test_prepare
 536                (struct efi_loaded_image_obj **image_objp,
 537                 struct efi_loaded_image **loaded_image_infop, const char *path,
 538                 const char *load_options_path)
 539{
 540        efi_status_t ret;
 541
 542        /* Construct a dummy device path */
 543        bootefi_device_path = efi_dp_from_mem(EFI_RESERVED_MEMORY_TYPE, 0, 0);
 544        if (!bootefi_device_path)
 545                return EFI_OUT_OF_RESOURCES;
 546
 547        bootefi_image_path = efi_dp_from_file(NULL, 0, path);
 548        if (!bootefi_image_path) {
 549                ret = EFI_OUT_OF_RESOURCES;
 550                goto failure;
 551        }
 552
 553        ret = bootefi_run_prepare(load_options_path, bootefi_device_path,
 554                                  bootefi_image_path, image_objp,
 555                                  loaded_image_infop);
 556        if (ret == EFI_SUCCESS)
 557                return ret;
 558
 559failure:
 560        efi_clear_bootdev();
 561        return ret;
 562}
 563
 564/**
 565 * bootefi_run_finish() - finish up after running an EFI test
 566 *
 567 * @loaded_image_info: Pointer to a struct which holds the loaded image info
 568 * @image_obj: Pointer to a struct which holds the loaded image object
 569 */
 570static void bootefi_run_finish(struct efi_loaded_image_obj *image_obj,
 571                               struct efi_loaded_image *loaded_image_info)
 572{
 573        efi_restore_gd();
 574        free(loaded_image_info->load_options);
 575        efi_delete_handle(&image_obj->header);
 576}
 577
 578/**
 579 * do_efi_selftest() - execute EFI selftest
 580 *
 581 * Return:      status code
 582 */
 583static int do_efi_selftest(void)
 584{
 585        struct efi_loaded_image_obj *image_obj;
 586        struct efi_loaded_image *loaded_image_info;
 587        efi_status_t ret;
 588
 589        ret = bootefi_test_prepare(&image_obj, &loaded_image_info,
 590                                   "\\selftest", "efi_selftest");
 591        if (ret != EFI_SUCCESS)
 592                return CMD_RET_FAILURE;
 593
 594        /* Execute the test */
 595        ret = EFI_CALL(efi_selftest(&image_obj->header, &systab));
 596        bootefi_run_finish(image_obj, loaded_image_info);
 597
 598        return ret != EFI_SUCCESS;
 599}
 600#endif /* CONFIG_CMD_BOOTEFI_SELFTEST */
 601
 602/**
 603 * do_bootefi() - execute `bootefi` command
 604 *
 605 * @cmdtp:      table entry describing command
 606 * @flag:       bitmap indicating how the command was invoked
 607 * @argc:       number of arguments
 608 * @argv:       command line arguments
 609 * Return:      status code
 610 */
 611static int do_bootefi(struct cmd_tbl *cmdtp, int flag, int argc,
 612                      char *const argv[])
 613{
 614        efi_status_t ret;
 615        void *fdt;
 616
 617        if (argc < 2)
 618                return CMD_RET_USAGE;
 619
 620        /* Initialize EFI drivers */
 621        ret = efi_init_obj_list();
 622        if (ret != EFI_SUCCESS) {
 623                log_err("Error: Cannot initialize UEFI sub-system, r = %lu\n",
 624                        ret & ~EFI_ERROR_MASK);
 625                return CMD_RET_FAILURE;
 626        }
 627
 628        if (argc > 2) {
 629                uintptr_t fdt_addr;
 630
 631                fdt_addr = simple_strtoul(argv[2], NULL, 16);
 632                fdt = map_sysmem(fdt_addr, 0);
 633        } else {
 634                fdt = EFI_FDT_USE_INTERNAL;
 635        }
 636        ret = efi_install_fdt(fdt);
 637        if (ret == EFI_INVALID_PARAMETER)
 638                return CMD_RET_USAGE;
 639        else if (ret != EFI_SUCCESS)
 640                return CMD_RET_FAILURE;
 641
 642        if (IS_ENABLED(CONFIG_CMD_BOOTEFI_BOOTMGR)) {
 643                if (!strcmp(argv[1], "bootmgr"))
 644                        return do_efibootmgr();
 645        }
 646#ifdef CONFIG_CMD_BOOTEFI_SELFTEST
 647        if (!strcmp(argv[1], "selftest"))
 648                return do_efi_selftest();
 649#endif
 650
 651        return do_bootefi_image(argv[1]);
 652}
 653
 654#ifdef CONFIG_SYS_LONGHELP
 655static char bootefi_help_text[] =
 656        "<image address> [fdt address]\n"
 657        "  - boot EFI payload stored at address <image address>.\n"
 658        "    If specified, the device tree located at <fdt address> gets\n"
 659        "    exposed as EFI configuration table.\n"
 660#ifdef CONFIG_CMD_BOOTEFI_HELLO
 661        "bootefi hello\n"
 662        "  - boot a sample Hello World application stored within U-Boot\n"
 663#endif
 664#ifdef CONFIG_CMD_BOOTEFI_SELFTEST
 665        "bootefi selftest [fdt address]\n"
 666        "  - boot an EFI selftest application stored within U-Boot\n"
 667        "    Use environment variable efi_selftest to select a single test.\n"
 668        "    Use 'setenv efi_selftest list' to enumerate all tests.\n"
 669#endif
 670#ifdef CONFIG_CMD_BOOTEFI_BOOTMGR
 671        "bootefi bootmgr [fdt address]\n"
 672        "  - load and boot EFI payload based on BootOrder/BootXXXX variables.\n"
 673        "\n"
 674        "    If specified, the device tree located at <fdt address> gets\n"
 675        "    exposed as EFI configuration table.\n"
 676#endif
 677        ;
 678#endif
 679
 680U_BOOT_CMD(
 681        bootefi, 3, 0, do_bootefi,
 682        "Boots an EFI payload from memory",
 683        bootefi_help_text
 684);
 685