cmd/bootefi.c

   1 /*
   2  *  EFI application loader
   3  *
   4  *  Copyright (c) 2016 Alexander Graf
   5  *
   6  *  SPDX-License-Identifier:     GPL-2.0+
   7  */
   8
   9 #include <common.h>
  10 #include <command.h>
  11 #include <efi_loader.h>
  12 #include <errno.h>
  13 #include <libfdt.h>
  14 #include <libfdt_env.h>
  15 #include <memalign.h>
  16 #include <asm/global_data.h>
  17
  18 DECLARE_GLOBAL_DATA_PTR;
  19
  20 /*
  21  * When booting using the "bootefi" command, we don't know which
  22  * physical device the file came from. So we create a pseudo-device
  23  * called "bootefi" with the device path /bootefi.
  24  *
  25  * In addition to the originating device we also declare the file path
  26  * of "bootefi" based loads to be /bootefi.
  27  */
  28 static struct efi_device_path_file_path bootefi_image_path[] = {
  29         {
  30                 .dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE,
  31                 .dp.sub_type = DEVICE_PATH_SUB_TYPE_FILE_PATH,
  32                 .dp.length = sizeof(bootefi_image_path[0]),
  33                 .str = { 'b','o','o','t','e','f','i' },
  34         }, {
  35                 .dp.type = DEVICE_PATH_TYPE_END,
  36                 .dp.sub_type = DEVICE_PATH_SUB_TYPE_END,
  37                 .dp.length = sizeof(bootefi_image_path[0]),
  38         }
  39 };
  40
  41 static struct efi_device_path_file_path bootefi_device_path[] = {
  42         {
  43                 .dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE,
  44                 .dp.sub_type = DEVICE_PATH_SUB_TYPE_FILE_PATH,
  45                 .dp.length = sizeof(bootefi_image_path[0]),
  46                 .str = { 'b','o','o','t','e','f','i' },
  47         }, {
  48                 .dp.type = DEVICE_PATH_TYPE_END,
  49                 .dp.sub_type = DEVICE_PATH_SUB_TYPE_END,
  50                 .dp.length = sizeof(bootefi_image_path[0]),
  51         }
  52 };
  53
  54 static efi_status_t bootefi_open_dp(void *handle, efi_guid_t *protocol,
  55                         void **protocol_interface, void *agent_handle,
  56                         void *controller_handle, uint32_t attributes)
  57 {
  58         *protocol_interface = bootefi_device_path;
  59         return EFI_SUCCESS;
  60 }
  61
  62 /* The EFI loaded_image interface for the image executed via "bootefi" */
  63 static struct efi_loaded_image loaded_image_info = {
  64         .device_handle = bootefi_device_path,
  65         .file_path = bootefi_image_path,
  66 };
  67
  68 /* The EFI object struct for the image executed via "bootefi" */
  69 static struct efi_object loaded_image_info_obj = {
  70         .handle = &loaded_image_info,
  71         .protocols = {
  72                 {
  73                         /*
  74                          * When asking for the loaded_image interface, just
  75                          * return handle which points to loaded_image_info
  76                          */
  77                         .guid = &efi_guid_loaded_image,
  78                         .open = &efi_return_handle,
  79                 },
  80                 {
  81                         /*
  82                          * When asking for the device path interface, return
  83                          * bootefi_device_path
  84                          */
  85                         .guid = &efi_guid_device_path,
  86                         .open = &bootefi_open_dp,
  87                 },
  88         },
  89 };
  90
  91 /* The EFI object struct for the device the "bootefi" image was loaded from */
  92 static struct efi_object bootefi_device_obj = {
  93         .handle = bootefi_device_path,
  94         .protocols = {
  95                 {
  96                         /* When asking for the device path interface, return
  97                          * bootefi_device_path */
  98                         .guid = &efi_guid_device_path,
  99                         .open = &bootefi_open_dp,
 100                 }
 101         },
 102 };
 103
 104 static void *copy_fdt(void *fdt)
 105 {
 106         u64 fdt_size = fdt_totalsize(fdt);
 107         unsigned long fdt_ram_start = -1L, fdt_pages;
 108         u64 new_fdt_addr;
 109         void *new_fdt;
 110         int i;
 111
 112         for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
 113                 u64 ram_start = gd->bd->bi_dram[i].start;
 114                 u64 ram_size = gd->bd->bi_dram[i].size;
 115
 116                 if (!ram_size)
 117                         continue;
 118
 119                 if (ram_start < fdt_ram_start)
 120                         fdt_ram_start = ram_start;
 121         }
 122
 123         /* Give us at least 4kb breathing room */
 124         fdt_size = ALIGN(fdt_size + 4096, 4096);
 125         fdt_pages = fdt_size >> EFI_PAGE_SHIFT;
 126
 127         /* Safe fdt location is at 128MB */
 128         new_fdt_addr = fdt_ram_start + (128 * 1024 * 1024) + fdt_size;
 129         if (efi_allocate_pages(1, EFI_BOOT_SERVICES_DATA, fdt_pages,
 130                                &new_fdt_addr) != EFI_SUCCESS) {
 131                 /* If we can't put it there, put it somewhere */
 132                 new_fdt_addr = (ulong)memalign(4096, fdt_size);
 133         }
 134         new_fdt = (void*)(ulong)new_fdt_addr;
 135         memcpy(new_fdt, fdt, fdt_totalsize(fdt));
 136         fdt_set_totalsize(new_fdt, fdt_size);
 137
 138         return new_fdt;
 139 }
 140
 141 /*
 142  * Load an EFI payload into a newly allocated piece of memory, register all
 143  * EFI objects it would want to access and jump to it.
 144  */
 145 static unsigned long do_bootefi_exec(void *efi, void *fdt)
 146 {
 147         ulong (*entry)(void *image_handle, struct efi_system_table *st);
 148         ulong fdt_pages, fdt_size, fdt_start, fdt_end;
 149         bootm_headers_t img = { 0 };
 150
 151         /*
 152          * gd lives in a fixed register which may get clobbered while we execute
 153          * the payload. So save it here and restore it on every callback entry
 154          */
 155         efi_save_gd();
 156
 157         if (fdt && !fdt_check_header(fdt)) {
 158                 /* Prepare fdt for payload */
 159                 fdt = copy_fdt(fdt);
 160
 161                 if (image_setup_libfdt(&img, fdt, 0, NULL)) {
 162                         printf("ERROR: Failed to process device tree\n");
 163                         return -EINVAL;
 164                 }
 165
 166                 /* Link to it in the efi tables */
 167                 systab.tables[0].guid = EFI_FDT_GUID;
 168                 systab.tables[0].table = fdt;
 169                 systab.nr_tables = 1;
 170
 171                 /* And reserve the space in the memory map */
 172                 fdt_start = ((ulong)fdt) & ~EFI_PAGE_MASK;
 173                 fdt_end = ((ulong)fdt) + fdt_totalsize(fdt);
 174                 fdt_size = (fdt_end - fdt_start) + EFI_PAGE_MASK;
 175                 fdt_pages = fdt_size >> EFI_PAGE_SHIFT;
 176                 /* Give a bootloader the chance to modify the device tree */
 177                 fdt_pages += 2;
 178                 efi_add_memory_map(fdt_start, fdt_pages,
 179                                    EFI_BOOT_SERVICES_DATA, true);
 180         } else {
 181                 printf("WARNING: Invalid device tree, expect boot to fail\n");
 182                 systab.nr_tables = 0;
 183         }
 184
 185         /* Load the EFI payload */
 186         entry = efi_load_pe(efi, &loaded_image_info);
 187         if (!entry)
 188                 return -ENOENT;
 189
 190         /* Initialize and populate EFI object list */
 191         INIT_LIST_HEAD(&efi_obj_list);
 192         list_add_tail(&loaded_image_info_obj.link, &efi_obj_list);
 193         list_add_tail(&bootefi_device_obj.link, &efi_obj_list);
 194 #ifdef CONFIG_PARTITIONS
 195         efi_disk_register();
 196 #endif
 197 #ifdef CONFIG_LCD
 198         efi_gop_register();
 199 #endif
 200
 201         /* Call our payload! */
 202 #ifdef DEBUG_EFI
 203         printf("%s:%d Jumping to 0x%lx\n", __func__, __LINE__, (long)entry);
 204 #endif
 205         return entry(&loaded_image_info, &systab);
 206 }
 207
 208
 209 /* Interpreter command to boot an arbitrary EFI image from memory */
 210 static int do_bootefi(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 211 {
 212         char *saddr, *sfdt;
 213         unsigned long addr, fdt_addr = 0;
 214         int r = 0;
 215
 216         if (argc < 2)
 217                 return 1;
 218         saddr = argv[1];
 219
 220         addr = simple_strtoul(saddr, NULL, 16);
 221
 222         if (argc > 2) {
 223                 sfdt = argv[2];
 224                 fdt_addr = simple_strtoul(sfdt, NULL, 16);
 225         }
 226
 227         printf("## Starting EFI application at 0x%08lx ...\n", addr);
 228         r = do_bootefi_exec((void *)addr, (void*)fdt_addr);
 229         printf("## Application terminated, r = %d\n", r);
 230
 231         if (r != 0)
 232                 r = 1;
 233
 234         return r;
 235 }
 236
 237 #ifdef CONFIG_SYS_LONGHELP
 238 static char bootefi_help_text[] =
 239         "<image address> [fdt address]\n"
 240         "  - boot EFI payload stored at address <image address>.\n"
 241         "    If specified, the device tree located at <fdt address> gets\n"
 242         "    exposed as EFI configuration table.\n";
 243 #endif
 244
 245 U_BOOT_CMD(
 246         bootefi, 3, 0, do_bootefi,
 247         "Boots an EFI payload from memory\n",
 248         bootefi_help_text
 249 );
 250
 251 void efi_set_bootdev(const char *dev, const char *devnr, const char *path)
 252 {
 253         __maybe_unused struct blk_desc *desc;
 254         char devname[32] = { 0 }; /* dp->str is u16[32] long */
 255         char *colon;
 256
 257         /* Assemble the condensed device name we use in efi_disk.c */
 258         snprintf(devname, sizeof(devname), "%s%s", dev, devnr);
 259         colon = strchr(devname, ':');
 260
 261 #ifdef CONFIG_ISO_PARTITION
 262         /* For ISOs we create partition block devices */
 263         desc = blk_get_dev(dev, simple_strtol(devnr, NULL, 10));
 264         if (desc && (desc->type != DEV_TYPE_UNKNOWN) &&
 265             (desc->part_type == PART_TYPE_ISO)) {
 266                 if (!colon)
 267                         snprintf(devname, sizeof(devname), "%s%s:1", dev,
 268                                  devnr);
 269                 colon = NULL;
 270         }
 271 #endif
 272
 273         if (colon)
 274                 *colon = '\0';
 275
 276         /* Patch bootefi_device_path to the target device */
 277         memset(bootefi_device_path[0].str, 0, sizeof(bootefi_device_path[0].str));
 278         ascii2unicode(bootefi_device_path[0].str, devname);
 279
 280         /* Patch bootefi_image_path to the target file path */
 281         memset(bootefi_image_path[0].str, 0, sizeof(bootefi_image_path[0].str));
 282         snprintf(devname, sizeof(devname), "%s", path);
 283         ascii2unicode(bootefi_image_path[0].str, devname);
 284 }