| /* |
| * Copyright (C) 2016 The Android Open Source Project |
| * |
| * SPDX-License-Identifier: BSD-2-Clause |
| */ |
| |
| #include <android_bootloader.h> |
| #include <android_bootloader_message.h> |
| |
| #include <android_ab.h> |
| #include <cli.h> |
| #include <common.h> |
| #include <log.h> |
| #include <malloc.h> |
| |
| #define ANDROID_PARTITION_BOOT "boot" |
| #define ANDROID_PARTITION_RECOVERY "recovery" |
| #define ANDROID_PARTITION_SYSTEM "system" |
| |
| #define ANDROID_ARG_SLOT_SUFFIX "androidboot.slot_suffix=" |
| #define ANDROID_ARG_ROOT "root=" |
| |
| static int android_bootloader_message_load( |
| struct blk_desc *dev_desc, |
| const disk_partition_t *part_info, |
| struct bootloader_message *message) |
| { |
| ulong message_blocks = sizeof(struct bootloader_message) / |
| part_info->blksz; |
| if (message_blocks > part_info->size) { |
| printf("misc partition too small.\n"); |
| return -1; |
| } |
| |
| if (blk_dread(dev_desc, part_info->start, message_blocks, message) != |
| message_blocks) { |
| printf("Could not read from misc partition\n"); |
| return -1; |
| } |
| debug("ANDROID: Loaded BCB, %lu blocks.\n", message_blocks); |
| return 0; |
| } |
| |
| static int android_bootloader_message_write( |
| struct blk_desc *dev_desc, |
| const disk_partition_t *part_info, |
| struct bootloader_message *message) |
| { |
| ulong message_blocks = sizeof(struct bootloader_message) / |
| part_info->blksz; |
| if (message_blocks > part_info->size) { |
| printf("misc partition too small.\n"); |
| return -1; |
| } |
| |
| if (blk_dwrite(dev_desc, part_info->start, message_blocks, message) != |
| message_blocks) { |
| printf("Could not write to misc partition\n"); |
| return -1; |
| } |
| debug("ANDROID: Wrote new BCB, %lu blocks.\n", message_blocks); |
| return 0; |
| } |
| |
| static enum android_boot_mode android_bootloader_load_and_clear_mode( |
| struct blk_desc *dev_desc, |
| const disk_partition_t *misc_part_info) |
| { |
| struct bootloader_message bcb; |
| |
| #ifdef CONFIG_FASTBOOT |
| char *bootloader_str; |
| |
| /* Check for message from bootloader stored in RAM from a previous boot. |
| */ |
| bootloader_str = (char *)CONFIG_FASTBOOT_BUF_ADDR; |
| if (!strcmp("reboot-bootloader", bootloader_str)) { |
| bootloader_str[0] = '\0'; |
| return ANDROID_BOOT_MODE_BOOTLOADER; |
| } |
| #endif |
| |
| /* Check and update the BCB message if needed. */ |
| if (android_bootloader_message_load(dev_desc, misc_part_info, &bcb) < |
| 0) { |
| printf("WARNING: Unable to load the BCB.\n"); |
| return ANDROID_BOOT_MODE_NORMAL; |
| } |
| |
| if (!strcmp("bootonce-bootloader", bcb.command)) { |
| /* Erase the message in the BCB since this value should be used |
| * only once. |
| */ |
| memset(bcb.command, 0, sizeof(bcb.command)); |
| android_bootloader_message_write(dev_desc, misc_part_info, |
| &bcb); |
| return ANDROID_BOOT_MODE_BOOTLOADER; |
| } |
| |
| if (!strcmp("boot-recovery", bcb.command)) |
| return ANDROID_BOOT_MODE_RECOVERY; |
| |
| return ANDROID_BOOT_MODE_NORMAL; |
| } |
| |
| /** |
| * Return the reboot reason string for the passed boot mode. |
| * |
| * @param mode The Android Boot mode. |
| * @return a pointer to the reboot reason string for mode. |
| */ |
| static const char *android_boot_mode_str(enum android_boot_mode mode) |
| { |
| switch (mode) { |
| case ANDROID_BOOT_MODE_NORMAL: |
| return "(none)"; |
| case ANDROID_BOOT_MODE_RECOVERY: |
| return "recovery"; |
| case ANDROID_BOOT_MODE_BOOTLOADER: |
| return "bootloader"; |
| } |
| return NULL; |
| } |
| |
| static int android_part_get_info_by_name_suffix(struct blk_desc *dev_desc, |
| const char *base_name, |
| const char *slot_suffix, |
| disk_partition_t *part_info) |
| { |
| char *part_name; |
| int part_num; |
| size_t part_name_len; |
| |
| part_name_len = strlen(base_name) + 1; |
| if (slot_suffix) |
| part_name_len += strlen(slot_suffix); |
| part_name = malloc(part_name_len); |
| if (!part_name) |
| return -1; |
| strcpy(part_name, base_name); |
| if (slot_suffix) |
| strcat(part_name, slot_suffix); |
| |
| part_num = part_get_info_by_name(dev_desc, part_name, part_info); |
| if (part_num < 0) { |
| debug("ANDROID: Could not find partition \"%s\"\n", part_name); |
| part_num = -1; |
| } |
| |
| free(part_name); |
| return part_num; |
| } |
| |
| static int android_bootloader_boot_bootloader(void) |
| { |
| const char *fastboot_cmd = env_get("fastbootcmd"); |
| |
| if (fastboot_cmd) |
| return run_command(fastboot_cmd, CMD_FLAG_ENV); |
| return -1; |
| } |
| |
| static int android_bootloader_boot_kernel(unsigned long kernel_address) |
| { |
| char kernel_addr_str[12]; |
| char *fdt_addr = env_get("fdtaddr"); |
| char *bootm_args[] = { |
| "bootm", kernel_addr_str, kernel_addr_str, fdt_addr, NULL }; |
| |
| sprintf(kernel_addr_str, "0x%lx", kernel_address); |
| |
| printf("Booting kernel at %s with fdt at %s...\n\n\n", |
| kernel_addr_str, fdt_addr); |
| do_bootm(NULL, 0, 4, bootm_args); |
| |
| return -1; |
| } |
| |
| static char *strjoin(const char **chunks, char separator) |
| { |
| int len, joined_len = 0; |
| char *ret, *current; |
| const char **p; |
| |
| for (p = chunks; *p; p++) |
| joined_len += strlen(*p) + 1; |
| |
| if (!joined_len) { |
| ret = malloc(1); |
| if (ret) |
| ret[0] = '\0'; |
| return ret; |
| } |
| |
| ret = malloc(joined_len); |
| current = ret; |
| if (!ret) |
| return ret; |
| |
| for (p = chunks; *p; p++) { |
| len = strlen(*p); |
| memcpy(current, *p, len); |
| current += len; |
| *current = separator; |
| current++; |
| } |
| /* Replace the last separator by a \0. */ |
| current[-1] = '\0'; |
| return ret; |
| } |
| |
| /** android_assemble_cmdline - Assemble the command line to pass to the kernel |
| * @return a newly allocated string |
| */ |
| static char *android_assemble_cmdline(const char *slot_suffix, |
| const char *extra_args) |
| { |
| const char *cmdline_chunks[16]; |
| const char **current_chunk = cmdline_chunks; |
| char *env_cmdline, *cmdline, *rootdev_input; |
| char *allocated_suffix = NULL; |
| char *allocated_rootdev = NULL; |
| unsigned long rootdev_len; |
| |
| env_cmdline = env_get("bootargs"); |
| if (env_cmdline) |
| *(current_chunk++) = env_cmdline; |
| |
| /* The |slot_suffix| needs to be passed to the kernel to know what |
| * slot to boot from. |
| */ |
| if (slot_suffix) { |
| allocated_suffix = malloc(strlen(ANDROID_ARG_SLOT_SUFFIX) + |
| strlen(slot_suffix)); |
| strcpy(allocated_suffix, ANDROID_ARG_SLOT_SUFFIX); |
| strcat(allocated_suffix, slot_suffix); |
| *(current_chunk++) = allocated_suffix; |
| } |
| |
| rootdev_input = env_get("android_rootdev"); |
| if (rootdev_input) { |
| rootdev_len = strlen(ANDROID_ARG_ROOT) + CONFIG_SYS_CBSIZE + 1; |
| allocated_rootdev = malloc(rootdev_len); |
| strcpy(allocated_rootdev, ANDROID_ARG_ROOT); |
| cli_simple_process_macros(rootdev_input, |
| allocated_rootdev + |
| strlen(ANDROID_ARG_ROOT)); |
| /* Make sure that the string is null-terminated since the |
| * previous could not copy to the end of the input string if it |
| * is too big. |
| */ |
| allocated_rootdev[rootdev_len - 1] = '\0'; |
| *(current_chunk++) = allocated_rootdev; |
| } |
| |
| if (extra_args) |
| *(current_chunk++) = extra_args; |
| |
| *(current_chunk++) = NULL; |
| cmdline = strjoin(cmdline_chunks, ' '); |
| free(allocated_suffix); |
| free(allocated_rootdev); |
| return cmdline; |
| } |
| |
| int android_bootloader_boot_flow(struct blk_desc *dev_desc, |
| const disk_partition_t *misc_part_info, |
| const char *slot, |
| unsigned long kernel_address) |
| { |
| enum android_boot_mode mode; |
| disk_partition_t boot_part_info; |
| int boot_part_num; |
| int ret; |
| char *command_line; |
| char slot_suffix[3]; |
| const char *mode_cmdline = NULL; |
| const char *boot_partition = ANDROID_PARTITION_BOOT; |
| #ifdef CONFIG_ANDROID_SYSTEM_AS_ROOT |
| int system_part_num |
| disk_partition_t system_part_info; |
| #endif |
| |
| /* Determine the boot mode and clear its value for the next boot if |
| * needed. |
| */ |
| mode = android_bootloader_load_and_clear_mode(dev_desc, misc_part_info); |
| printf("ANDROID: reboot reason: \"%s\"\n", android_boot_mode_str(mode)); |
| |
| switch (mode) { |
| case ANDROID_BOOT_MODE_NORMAL: |
| #ifdef CONFIG_ANDROID_SYSTEM_AS_ROOT |
| /* In normal mode, we load the kernel from "boot" but append |
| * "skip_initramfs" to the cmdline to make it ignore the |
| * recovery initramfs in the boot partition. |
| */ |
| mode_cmdline = "skip_initramfs"; |
| #endif |
| break; |
| case ANDROID_BOOT_MODE_RECOVERY: |
| #ifdef CONFIG_ANDROID_SYSTEM_AS_ROOT |
| /* In recovery mode we still boot the kernel from "boot" but |
| * don't skip the initramfs so it boots to recovery. |
| */ |
| #else |
| boot_partition = ANDROID_PARTITION_RECOVERY; |
| #endif |
| break; |
| case ANDROID_BOOT_MODE_BOOTLOADER: |
| /* Bootloader mode enters fastboot. If this operation fails we |
| * simply return since we can't recover from this situation by |
| * switching to another slot. |
| */ |
| return android_bootloader_boot_bootloader(); |
| } |
| |
| /* Look for an optional slot suffix override. */ |
| if (!slot || !slot[0]) |
| slot = env_get("android_slot_suffix"); |
| |
| slot_suffix[0] = '\0'; |
| if (slot && slot[0]) { |
| slot_suffix[0] = '_'; |
| slot_suffix[1] = slot[0]; |
| slot_suffix[2] = '\0'; |
| } else { |
| #ifdef CONFIG_ANDROID_AB |
| bool normal_boot = (mode == ANDROID_BOOT_MODE_NORMAL); |
| int slot_num = ab_select_slot(dev_desc, misc_part_info, normal_boot); |
| if (slot_num < 0) { |
| log_err("Could not determine Android boot slot.\n"); |
| return -1; |
| } |
| slot_suffix[0] = '_'; |
| slot_suffix[1] = BOOT_SLOT_NAME(slot_num); |
| slot_suffix[2] = '\0'; |
| #endif |
| } |
| |
| /* Load the kernel from the desired "boot" partition. */ |
| boot_part_num = |
| android_part_get_info_by_name_suffix(dev_desc, boot_partition, |
| slot_suffix, &boot_part_info); |
| if (boot_part_num < 0) |
| return -1; |
| debug("ANDROID: Loading kernel from \"%s\", partition %d.\n", |
| boot_part_info.name, boot_part_num); |
| |
| #ifdef CONFIG_ANDROID_SYSTEM_AS_ROOT |
| system_part_num = |
| android_part_get_info_by_name_suffix(dev_desc, |
| ANDROID_PARTITION_SYSTEM, |
| slot_suffix, |
| &system_part_info); |
| if (system_part_num < 0) |
| return -1; |
| debug("ANDROID: Using system image from \"%s\", partition %d.\n", |
| system_part_info.name, system_part_num); |
| #endif |
| |
| ret = android_image_load(dev_desc, &boot_part_info, kernel_address, |
| -1UL); |
| if (ret < 0) |
| return ret; |
| |
| #ifdef CONFIG_ANDROID_SYSTEM_AS_ROOT |
| /* Set Android root variables. */ |
| env_set_ulong("android_root_devnum", dev_desc->devnum); |
| env_set_ulong("android_root_partnum", system_part_num); |
| #endif |
| env_set("android_slotsufix", slot_suffix); |
| |
| /* Assemble the command line */ |
| command_line = android_assemble_cmdline(slot_suffix, mode_cmdline); |
| env_set("bootargs", command_line); |
| |
| debug("ANDROID: bootargs: \"%s\"\n", command_line); |
| |
| android_bootloader_boot_kernel(kernel_address); |
| |
| /* TODO: If the kernel doesn't boot mark the selected slot as bad. */ |
| return -1; |
| } |