drivers/fastboot/fb_mmc.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright 2014 Broadcom Corporation.
   4  */
   5
   6 #include <config.h>
   7 #include <common.h>
   8 #include <blk.h>
   9 #include <fastboot.h>
  10 #include <fb_mmc.h>
  11 #include <image-sparse.h>
  12 #include <part.h>
  13 #include <mmc.h>
  14 #include <div64.h>
  15 #include <linux/compat.h>
  16 #include <android_image.h>
  17
  18 #define BOOT_PARTITION_NAME "boot"
  19
  20 struct fb_mmc_sparse {
  21         struct blk_desc *dev_desc;
  22 };
  23
  24 static int part_get_info_by_name_or_alias(struct blk_desc *dev_desc,
  25                 const char *name, disk_partition_t *info)
  26 {
  27         int ret;
  28
  29         ret = part_get_info_by_name(dev_desc, name, info);
  30         if (ret < 0) {
  31                 /* strlen("fastboot_partition_alias_") + 32(part_name) + 1 */
  32                 char env_alias_name[25 + 32 + 1];
  33                 char *aliased_part_name;
  34
  35                 /* check for alias */
  36                 strcpy(env_alias_name, "fastboot_partition_alias_");
  37                 strncat(env_alias_name, name, 32);
  38                 aliased_part_name = env_get(env_alias_name);
  39                 if (aliased_part_name != NULL)
  40                         ret = part_get_info_by_name(dev_desc,
  41                                         aliased_part_name, info);
  42         }
  43         return ret;
  44 }
  45
  46 static lbaint_t fb_mmc_sparse_write(struct sparse_storage *info,
  47                 lbaint_t blk, lbaint_t blkcnt, const void *buffer)
  48 {
  49         struct fb_mmc_sparse *sparse = info->priv;
  50         struct blk_desc *dev_desc = sparse->dev_desc;
  51
  52         return blk_dwrite(dev_desc, blk, blkcnt, buffer);
  53 }
  54
  55 static lbaint_t fb_mmc_sparse_reserve(struct sparse_storage *info,
  56                 lbaint_t blk, lbaint_t blkcnt)
  57 {
  58         return blkcnt;
  59 }
  60
  61 static void write_raw_image(struct blk_desc *dev_desc, disk_partition_t *info,
  62                 const char *part_name, void *buffer,
  63                 unsigned int download_bytes, char *response)
  64 {
  65         lbaint_t blkcnt;
  66         lbaint_t blks;
  67
  68         /* determine number of blocks to write */
  69         blkcnt = ((download_bytes + (info->blksz - 1)) & ~(info->blksz - 1));
  70         blkcnt = lldiv(blkcnt, info->blksz);
  71
  72         if (blkcnt > info->size) {
  73                 pr_err("too large for partition: '%s'\n", part_name);
  74                 fastboot_fail("too large for partition", response);
  75                 return;
  76         }
  77
  78         puts("Flashing Raw Image\n");
  79
  80         blks = blk_dwrite(dev_desc, info->start, blkcnt, buffer);
  81         if (blks != blkcnt) {
  82                 pr_err("failed writing to device %d\n", dev_desc->devnum);
  83                 fastboot_fail("failed writing to device", response);
  84                 return;
  85         }
  86
  87         printf("........ wrote " LBAFU " bytes to '%s'\n", blkcnt * info->blksz,
  88                part_name);
  89         fastboot_okay(NULL, response);
  90 }
  91
  92 #ifdef CONFIG_ANDROID_BOOT_IMAGE
  93 /**
  94  * Read Android boot image header from boot partition.
  95  *
  96  * @param[in] dev_desc MMC device descriptor
  97  * @param[in] info Boot partition info
  98  * @param[out] hdr Where to store read boot image header
  99  *
 100  * @return Boot image header sectors count or 0 on error
 101  */
 102 static lbaint_t fb_mmc_get_boot_header(struct blk_desc *dev_desc,
 103                                        disk_partition_t *info,
 104                                        struct andr_img_hdr *hdr,
 105                                        char *response)
 106 {
 107         ulong sector_size;              /* boot partition sector size */
 108         lbaint_t hdr_sectors;           /* boot image header sectors count */
 109         int res;
 110
 111         /* Calculate boot image sectors count */
 112         sector_size = info->blksz;
 113         hdr_sectors = DIV_ROUND_UP(sizeof(struct andr_img_hdr), sector_size);
 114         if (hdr_sectors == 0) {
 115                 pr_err("invalid number of boot sectors: 0\n");
 116                 fastboot_fail("invalid number of boot sectors: 0", response);
 117                 return 0;
 118         }
 119
 120         /* Read the boot image header */
 121         res = blk_dread(dev_desc, info->start, hdr_sectors, (void *)hdr);
 122         if (res != hdr_sectors) {
 123                 pr_err("cannot read header from boot partition\n");
 124                 fastboot_fail("cannot read header from boot partition",
 125                               response);
 126                 return 0;
 127         }
 128
 129         /* Check boot header magic string */
 130         res = android_image_check_header(hdr);
 131         if (res != 0) {
 132                 pr_err("bad boot image magic\n");
 133                 fastboot_fail("boot partition not initialized", response);
 134                 return 0;
 135         }
 136
 137         return hdr_sectors;
 138 }
 139
 140 /**
 141  * Write downloaded zImage to boot partition and repack it properly.
 142  *
 143  * @param dev_desc MMC device descriptor
 144  * @param download_buffer Address to fastboot buffer with zImage in it
 145  * @param download_bytes Size of fastboot buffer, in bytes
 146  *
 147  * @return 0 on success or -1 on error
 148  */
 149 static int fb_mmc_update_zimage(struct blk_desc *dev_desc,
 150                                 void *download_buffer,
 151                                 unsigned int download_bytes,
 152                                 char *response)
 153 {
 154         uintptr_t hdr_addr;                     /* boot image header address */
 155         struct andr_img_hdr *hdr;               /* boot image header */
 156         lbaint_t hdr_sectors;                   /* boot image header sectors */
 157         u8 *ramdisk_buffer;
 158         u32 ramdisk_sector_start;
 159         u32 ramdisk_sectors;
 160         u32 kernel_sector_start;
 161         u32 kernel_sectors;
 162         u32 sectors_per_page;
 163         disk_partition_t info;
 164         int res;
 165
 166         puts("Flashing zImage\n");
 167
 168         /* Get boot partition info */
 169         res = part_get_info_by_name(dev_desc, BOOT_PARTITION_NAME, &info);
 170         if (res < 0) {
 171                 pr_err("cannot find boot partition\n");
 172                 fastboot_fail("cannot find boot partition", response);
 173                 return -1;
 174         }
 175
 176         /* Put boot image header in fastboot buffer after downloaded zImage */
 177         hdr_addr = (uintptr_t)download_buffer + ALIGN(download_bytes, PAGE_SIZE);
 178         hdr = (struct andr_img_hdr *)hdr_addr;
 179
 180         /* Read boot image header */
 181         hdr_sectors = fb_mmc_get_boot_header(dev_desc, &info, hdr, response);
 182         if (hdr_sectors == 0) {
 183                 pr_err("unable to read boot image header\n");
 184                 fastboot_fail("unable to read boot image header", response);
 185                 return -1;
 186         }
 187
 188         /* Check if boot image has second stage in it (we don't support it) */
 189         if (hdr->second_size > 0) {
 190                 pr_err("moving second stage is not supported yet\n");
 191                 fastboot_fail("moving second stage is not supported yet",
 192                               response);
 193                 return -1;
 194         }
 195
 196         /* Extract ramdisk location */
 197         sectors_per_page = hdr->page_size / info.blksz;
 198         ramdisk_sector_start = info.start + sectors_per_page;
 199         ramdisk_sector_start += DIV_ROUND_UP(hdr->kernel_size, hdr->page_size) *
 200                                              sectors_per_page;
 201         ramdisk_sectors = DIV_ROUND_UP(hdr->ramdisk_size, hdr->page_size) *
 202                                        sectors_per_page;
 203
 204         /* Read ramdisk and put it in fastboot buffer after boot image header */
 205         ramdisk_buffer = (u8 *)hdr + (hdr_sectors * info.blksz);
 206         res = blk_dread(dev_desc, ramdisk_sector_start, ramdisk_sectors,
 207                         ramdisk_buffer);
 208         if (res != ramdisk_sectors) {
 209                 pr_err("cannot read ramdisk from boot partition\n");
 210                 fastboot_fail("cannot read ramdisk from boot partition",
 211                               response);
 212                 return -1;
 213         }
 214
 215         /* Write new kernel size to boot image header */
 216         hdr->kernel_size = download_bytes;
 217         res = blk_dwrite(dev_desc, info.start, hdr_sectors, (void *)hdr);
 218         if (res == 0) {
 219                 pr_err("cannot writeback boot image header\n");
 220                 fastboot_fail("cannot write back boot image header", response);
 221                 return -1;
 222         }
 223
 224         /* Write the new downloaded kernel */
 225         kernel_sector_start = info.start + sectors_per_page;
 226         kernel_sectors = DIV_ROUND_UP(hdr->kernel_size, hdr->page_size) *
 227                                       sectors_per_page;
 228         res = blk_dwrite(dev_desc, kernel_sector_start, kernel_sectors,
 229                          download_buffer);
 230         if (res == 0) {
 231                 pr_err("cannot write new kernel\n");
 232                 fastboot_fail("cannot write new kernel", response);
 233                 return -1;
 234         }
 235
 236         /* Write the saved ramdisk back */
 237         ramdisk_sector_start = info.start + sectors_per_page;
 238         ramdisk_sector_start += DIV_ROUND_UP(hdr->kernel_size, hdr->page_size) *
 239                                              sectors_per_page;
 240         res = blk_dwrite(dev_desc, ramdisk_sector_start, ramdisk_sectors,
 241                          ramdisk_buffer);
 242         if (res == 0) {
 243                 pr_err("cannot write back original ramdisk\n");
 244                 fastboot_fail("cannot write back original ramdisk", response);
 245                 return -1;
 246         }
 247
 248         puts("........ zImage was updated in boot partition\n");
 249         fastboot_okay(NULL, response);
 250         return 0;
 251 }
 252 #endif
 253
 254 void fb_mmc_flash_write(const char *cmd, void *download_buffer,
 255                         unsigned int download_bytes, char *response)
 256 {
 257         struct blk_desc *dev_desc;
 258         disk_partition_t info;
 259
 260         dev_desc = blk_get_dev("mmc", CONFIG_FASTBOOT_FLASH_MMC_DEV);
 261         if (!dev_desc || dev_desc->type == DEV_TYPE_UNKNOWN) {
 262                 pr_err("invalid mmc device\n");
 263                 fastboot_fail("invalid mmc device", response);
 264                 return;
 265         }
 266
 267 #if CONFIG_IS_ENABLED(EFI_PARTITION)
 268         if (strcmp(cmd, CONFIG_FASTBOOT_GPT_NAME) == 0) {
 269                 printf("%s: updating MBR, Primary and Backup GPT(s)\n",
 270                        __func__);
 271                 if (is_valid_gpt_buf(dev_desc, download_buffer)) {
 272                         printf("%s: invalid GPT - refusing to write to flash\n",
 273                                __func__);
 274                         fastboot_fail("invalid GPT partition", response);
 275                         return;
 276                 }
 277                 if (write_mbr_and_gpt_partitions(dev_desc, download_buffer)) {
 278                         printf("%s: writing GPT partitions failed\n", __func__);
 279                         fastboot_fail("writing GPT partitions failed",
 280                                       response);
 281                         return;
 282                 }
 283                 printf("........ success\n");
 284                 fastboot_okay(NULL, response);
 285                 return;
 286         }
 287 #endif
 288
 289 #if CONFIG_IS_ENABLED(DOS_PARTITION)
 290         if (strcmp(cmd, CONFIG_FASTBOOT_MBR_NAME) == 0) {
 291                 printf("%s: updating MBR\n", __func__);
 292                 if (is_valid_dos_buf(download_buffer)) {
 293                         printf("%s: invalid MBR - refusing to write to flash\n",
 294                                __func__);
 295                         fastboot_fail("invalid MBR partition", response);
 296                         return;
 297                 }
 298                 if (write_mbr_partition(dev_desc, download_buffer)) {
 299                         printf("%s: writing MBR partition failed\n", __func__);
 300                         fastboot_fail("writing MBR partition failed",
 301                                       response);
 302                         return;
 303                 }
 304                 printf("........ success\n");
 305                 fastboot_okay(NULL, response);
 306                 return;
 307         }
 308 #endif
 309
 310 #ifdef CONFIG_ANDROID_BOOT_IMAGE
 311         if (strncasecmp(cmd, "zimage", 6) == 0) {
 312                 fb_mmc_update_zimage(dev_desc, download_buffer,
 313                                      download_bytes, response);
 314                 return;
 315         }
 316 #endif
 317
 318         if (part_get_info_by_name_or_alias(dev_desc, cmd, &info) < 0) {
 319                 pr_err("cannot find partition: '%s'\n", cmd);
 320                 fastboot_fail("cannot find partition", response);
 321                 return;
 322         }
 323
 324         if (is_sparse_image(download_buffer)) {
 325                 struct fb_mmc_sparse sparse_priv;
 326                 struct sparse_storage sparse;
 327                 int err;
 328
 329                 sparse_priv.dev_desc = dev_desc;
 330
 331                 sparse.blksz = info.blksz;
 332                 sparse.start = info.start;
 333                 sparse.size = info.size;
 334                 sparse.write = fb_mmc_sparse_write;
 335                 sparse.reserve = fb_mmc_sparse_reserve;
 336                 sparse.mssg = fastboot_fail;
 337
 338                 printf("Flashing sparse image at offset " LBAFU "\n",
 339                        sparse.start);
 340
 341                 sparse.priv = &sparse_priv;
 342                 err = write_sparse_image(&sparse, cmd, download_buffer,
 343                                          response);
 344                 if (!err)
 345                         fastboot_okay(NULL, response);
 346         } else {
 347                 write_raw_image(dev_desc, &info, cmd, download_buffer,
 348                                 download_bytes, response);
 349         }
 350 }
 351
 352 void fb_mmc_erase(const char *cmd, char *response)
 353 {
 354         int ret;
 355         struct blk_desc *dev_desc;
 356         disk_partition_t info;
 357         lbaint_t blks, blks_start, blks_size, grp_size;
 358         struct mmc *mmc = find_mmc_device(CONFIG_FASTBOOT_FLASH_MMC_DEV);
 359
 360         if (mmc == NULL) {
 361                 pr_err("invalid mmc device\n");
 362                 fastboot_fail("invalid mmc device", response);
 363                 return;
 364         }
 365
 366         dev_desc = blk_get_dev("mmc", CONFIG_FASTBOOT_FLASH_MMC_DEV);
 367         if (!dev_desc || dev_desc->type == DEV_TYPE_UNKNOWN) {
 368                 pr_err("invalid mmc device\n");
 369                 fastboot_fail("invalid mmc device", response);
 370                 return;
 371         }
 372
 373         ret = part_get_info_by_name_or_alias(dev_desc, cmd, &info);
 374         if (ret < 0) {
 375                 pr_err("cannot find partition: '%s'\n", cmd);
 376                 fastboot_fail("cannot find partition", response);
 377                 return;
 378         }
 379
 380         /* Align blocks to erase group size to avoid erasing other partitions */
 381         grp_size = mmc->erase_grp_size;
 382         blks_start = (info.start + grp_size - 1) & ~(grp_size - 1);
 383         if (info.size >= grp_size)
 384                 blks_size = (info.size - (blks_start - info.start)) &
 385                                 (~(grp_size - 1));
 386         else
 387                 blks_size = 0;
 388
 389         printf("Erasing blocks " LBAFU " to " LBAFU " due to alignment\n",
 390                blks_start, blks_start + blks_size);
 391
 392         blks = blk_derase(dev_desc, blks_start, blks_size);
 393         if (blks != blks_size) {
 394                 pr_err("failed erasing from device %d\n", dev_desc->devnum);
 395                 fastboot_fail("failed erasing from device", response);
 396                 return;
 397         }
 398
 399         printf("........ erased " LBAFU " bytes from '%s'\n",
 400                blks_size * info.blksz, cmd);
 401         fastboot_okay(NULL, response);
 402 }