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 <malloc.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         void *new_fdt;
 108
 109         /* Give us 64kb breathing room */
 110         fdt_size += 64 * 1024;
 111
 112         new_fdt = malloc(fdt_size);
 113         memcpy(new_fdt, fdt, fdt_totalsize(fdt));
 114         fdt_set_totalsize(new_fdt, fdt_size);
 115
 116         return new_fdt;
 117 }
 118
 119 /*
 120  * Load an EFI payload into a newly allocated piece of memory, register all
 121  * EFI objects it would want to access and jump to it.
 122  */
 123 static unsigned long do_bootefi_exec(void *efi)
 124 {
 125         ulong (*entry)(void *image_handle, struct efi_system_table *st);
 126         ulong fdt_pages, fdt_size, fdt_start, fdt_end;
 127         bootm_headers_t img = { 0 };
 128         void *fdt = working_fdt;
 129
 130         /*
 131          * gd lives in a fixed register which may get clobbered while we execute
 132          * the payload. So save it here and restore it on every callback entry
 133          */
 134         efi_save_gd();
 135
 136         /* Update system table to point to our currently loaded FDT */
 137
 138         /* Fall back to included fdt if none was manually loaded */
 139         if (!fdt && gd->fdt_blob)
 140                 fdt = (void *)gd->fdt_blob;
 141
 142         if (fdt) {
 143                 /* Prepare fdt for payload */
 144                 fdt = copy_fdt(fdt);
 145
 146                 if (image_setup_libfdt(&img, fdt, 0, NULL)) {
 147                         printf("ERROR: Failed to process device tree\n");
 148                         return -EINVAL;
 149                 }
 150
 151                 /* Link to it in the efi tables */
 152                 systab.tables[0].guid = EFI_FDT_GUID;
 153                 systab.tables[0].table = fdt;
 154                 systab.nr_tables = 1;
 155
 156                 /* And reserve the space in the memory map */
 157                 fdt_start = ((ulong)fdt) & ~EFI_PAGE_MASK;
 158                 fdt_end = ((ulong)fdt) + fdt_totalsize(fdt);
 159                 fdt_size = (fdt_end - fdt_start) + EFI_PAGE_MASK;
 160                 fdt_pages = fdt_size >> EFI_PAGE_SHIFT;
 161                 /* Give a bootloader the chance to modify the device tree */
 162                 fdt_pages += 2;
 163                 efi_add_memory_map(fdt_start, fdt_pages,
 164                                    EFI_BOOT_SERVICES_DATA, true);
 165         } else {
 166                 printf("WARNING: No device tree loaded, expect boot to fail\n");
 167                 systab.nr_tables = 0;
 168         }
 169
 170         /* Load the EFI payload */
 171         entry = efi_load_pe(efi, &loaded_image_info);
 172         if (!entry)
 173                 return -ENOENT;
 174
 175         /* Initialize and populate EFI object list */
 176         INIT_LIST_HEAD(&efi_obj_list);
 177         list_add_tail(&loaded_image_info_obj.link, &efi_obj_list);
 178         list_add_tail(&bootefi_device_obj.link, &efi_obj_list);
 179 #ifdef CONFIG_PARTITIONS
 180         efi_disk_register();
 181 #endif
 182 #ifdef CONFIG_LCD
 183         efi_gop_register();
 184 #endif
 185
 186         /* Call our payload! */
 187 #ifdef DEBUG_EFI
 188         printf("%s:%d Jumping to 0x%lx\n", __func__, __LINE__, (long)entry);
 189 #endif
 190         return entry(&loaded_image_info, &systab);
 191 }
 192
 193
 194 /* Interpreter command to boot an arbitrary EFI image from memory */
 195 static int do_bootefi(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 196 {
 197         char *saddr;
 198         unsigned long addr;
 199         int r = 0;
 200
 201         if (argc < 2)
 202                 return 1;
 203         saddr = argv[1];
 204
 205         addr = simple_strtoul(saddr, NULL, 16);
 206
 207         printf("## Starting EFI application at 0x%08lx ...\n", addr);
 208         r = do_bootefi_exec((void *)addr);
 209         printf("## Application terminated, r = %d\n", r);
 210
 211         if (r != 0)
 212                 r = 1;
 213
 214         return r;
 215 }
 216
 217 #ifdef CONFIG_SYS_LONGHELP
 218 static char bootefi_help_text[] =
 219         "<image address>\n"
 220         "  - boot EFI payload stored at address <image address>\n"
 221         "\n"
 222         "Since most EFI payloads want to have a device tree provided, please\n"
 223         "make sure you load a device tree using the fdt addr command before\n"
 224         "executing bootefi.\n";
 225 #endif
 226
 227 U_BOOT_CMD(
 228         bootefi, 2, 0, do_bootefi,
 229         "Boots an EFI payload from memory\n",
 230         bootefi_help_text
 231 );
 232
 233 void efi_set_bootdev(const char *dev, const char *devnr, const char *path)
 234 {
 235         __maybe_unused struct blk_desc *desc;
 236         char devname[32] = { 0 }; /* dp->str is u16[32] long */
 237         char *colon;
 238
 239         /* Assemble the condensed device name we use in efi_disk.c */
 240         snprintf(devname, sizeof(devname), "%s%s", dev, devnr);
 241         colon = strchr(devname, ':');
 242
 243 #ifdef CONFIG_ISO_PARTITION
 244         /* For ISOs we create partition block devices */
 245         desc = blk_get_dev(dev, simple_strtol(devnr, NULL, 10));
 246         if (desc && (desc->type != DEV_TYPE_UNKNOWN) &&
 247             (desc->part_type == PART_TYPE_ISO)) {
 248                 if (!colon)
 249                         snprintf(devname, sizeof(devname), "%s%s:1", dev,
 250                                  devnr);
 251                 colon = NULL;
 252         }
 253 #endif
 254
 255         if (colon)
 256                 *colon = '\0';
 257
 258         /* Patch bootefi_device_path to the target device */
 259         memset(bootefi_device_path[0].str, 0, sizeof(bootefi_device_path[0].str));
 260         ascii2unicode(bootefi_device_path[0].str, devname);
 261
 262         /* Patch bootefi_image_path to the target file path */
 263         memset(bootefi_image_path[0].str, 0, sizeof(bootefi_image_path[0].str));
 264         snprintf(devname, sizeof(devname), "%s", path);
 265         ascii2unicode(bootefi_image_path[0].str, devname);
 266 }