blob: 4334079b907a5471b2a3a19153b9a33009b88d37 [file] [log] [blame]
/*
* 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;
}