On Thu 13 Jun 2024 at 16:18, Mattijs Korpershoek <mkorpersh...@baylibre.com> wrote:
> Android boot flow is a bit different than a regular Linux distro. > Android relies on multiple partitions in order to boot. > > A typical boot flow would be: > 1. Parse the Bootloader Control Block (BCB, misc partition) > 2. If BCB requested bootonce-bootloader, start fastboot and wait. > 3. If BCB requested recovery or normal android, run the following: > 3.a. Get slot (A/B) from BCB > 3.b. Run AVB (Android Verified Boot) on boot partitions > 3.c. Load boot and vendor_boot partitions > 3.d. Load device-tree, ramdisk and boot > > The AOSP documentation has more details at [1], [2], [3] > > This has been implemented via complex boot scripts such as [4]. > However, these boot script are neither very maintainable nor generic. > Moreover, DISTRO_DEFAULTS is being deprecated [5]. > > Add a generic Android bootflow implementation for bootstd. > For this initial version, only boot image v4 is supported. > > [1] https://source.android.com/docs/core/architecture/bootloader > [2] https://source.android.com/docs/core/architecture/partitions > [3] https://source.android.com/docs/core/architecture/partitions/generic-boot > [4] > https://source.denx.de/u-boot/u-boot/-/blob/master/include/configs/meson64_android.h > [5] https://lore.kernel.org/r/all/20230914165615.1058529-17-...@chromium.org/ > > Reviewed-by: Simon Glass <s...@chromium.org> > Signed-off-by: Mattijs Korpershoek <mkorpersh...@baylibre.com> > --- > MAINTAINERS | 7 + > boot/Kconfig | 16 ++ > boot/Makefile | 2 + > boot/bootmeth_android.c | 553 > ++++++++++++++++++++++++++++++++++++++++++++++++ > boot/bootmeth_android.h | 29 +++ > doc/develop/bootstd.rst | 6 + > 6 files changed, 613 insertions(+) > > diff --git a/MAINTAINERS b/MAINTAINERS > index 66783d636e3d..6d2b87720565 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -939,6 +939,13 @@ F: include/bootstd.h > F: net/eth_bootdevice.c > F: test/boot/ > > +BOOTMETH_ANDROID > +M: Mattijs Korpershoek <mkorpersh...@baylibre.com> > +S: Maintained > +T: git https://source.denx.de/u-boot/custodians/u-boot-dfu.git > +F: boot/bootmeth_android.c > +F: boot/bootmeth_android.h > + > BTRFS > M: Marek Beh.n <ka...@kernel.org> > R: Qu Wenruo <w...@suse.com> > diff --git a/boot/Kconfig b/boot/Kconfig > index 6f3096c15a6f..88266c8d2ed3 100644 > --- a/boot/Kconfig > +++ b/boot/Kconfig > @@ -494,6 +494,22 @@ config BOOTMETH_GLOBAL > EFI bootmgr, since they take full control over which bootdevs are > selected to boot. > > +config BOOTMETH_ANDROID > + bool "Bootdev support for Android" > + depends on X86 || ARM || SANDBOX > + select ANDROID_AB > + select ANDROID_BOOT_IMAGE > + select CMD_BCB > + select CMD_FASTBOOT > + select PARTITION_TYPE_GUID > + select PARTITION_UUIDS > + help > + Enables support for booting Android using bootstd. Android requires > + multiple partitions (misc, boot, vbmeta, ...) in storage for booting. > + > + Note that only MMC bootdevs are supported at present. This is caused > + by AVB being limited to MMC devices only. > + > config BOOTMETH_CROS > bool "Bootdev support for Chromium OS" > depends on X86 || ARM || SANDBOX > diff --git a/boot/Makefile b/boot/Makefile > index 84ccfeaecec4..75d1cd46fabf 100644 > --- a/boot/Makefile > +++ b/boot/Makefile > @@ -66,3 +66,5 @@ obj-$(CONFIG_$(SPL_TPL_)BOOTMETH_VBE_REQUEST) += > vbe_request.o > obj-$(CONFIG_$(SPL_TPL_)BOOTMETH_VBE_SIMPLE) += vbe_simple.o > obj-$(CONFIG_$(SPL_TPL_)BOOTMETH_VBE_SIMPLE_FW) += vbe_simple_fw.o > obj-$(CONFIG_$(SPL_TPL_)BOOTMETH_VBE_SIMPLE_OS) += vbe_simple_os.o > + > +obj-$(CONFIG_$(SPL_TPL_)BOOTMETH_ANDROID) += bootmeth_android.o > diff --git a/boot/bootmeth_android.c b/boot/bootmeth_android.c > new file mode 100644 > index 000000000000..6e8d3e615db0 > --- /dev/null > +++ b/boot/bootmeth_android.c > @@ -0,0 +1,553 @@ > +// SPDX-License-Identifier: GPL-2.0+ > +/* > + * Bootmeth for Android > + * > + * Copyright (C) 2024 BayLibre, SAS > + * Written by Mattijs Korpershoek <mkorpersh...@baylibre.com> > + */ > +#define LOG_CATEGORY UCLASS_BOOTSTD > + > +#include <android_ab.h> > +#include <android_image.h> > +#if CONFIG_IS_ENABLED(AVB_VERIFY) > +#include <avb_verify.h> > +#endif > +#include <bcb.h> > +#include <blk.h> > +#include <bootflow.h> > +#include <bootm.h> > +#include <bootmeth.h> > +#include <dm.h> > +#include <image.h> > +#include <malloc.h> > +#include <mapmem.h> > +#include <part.h> > +#include "bootmeth_android.h" > + > +#define BCB_FIELD_COMMAND_SZ 32 > +#define BCB_PART_NAME "misc" > +#define BOOT_PART_NAME "boot" > +#define VENDOR_BOOT_PART_NAME "vendor_boot" > + > +/** > + * struct android_priv - Private data > + * > + * This is read from the disk and recorded for use when the full Android > + * kernel must be loaded and booted > + * > + * @boot_mode: Requested boot mode (normal, recovery, bootloader) > + * @slot: Nul-terminated partition slot suffix read from BCB ("a\0" or "b\0") > + * @header_version: Android boot image header version > + */ > +struct android_priv { > + enum android_boot_mode boot_mode; > + char slot[2]; > + u32 header_version; > +}; > + > +static int android_check(struct udevice *dev, struct bootflow_iter *iter) > +{ > + /* This only works on mmc devices */ > + if (bootflow_iter_check_mmc(iter)) > + return log_msg_ret("mmc", -ENOTSUPP); > + > + /* > + * This only works on whole devices, as multiple > + * partitions are needed to boot Android > + */ > + if (iter->part != 0) > + return log_msg_ret("mmc part", -ENOTSUPP); > + > + return 0; > +} > + > +static int scan_boot_part(struct udevice *blk, struct android_priv *priv) > +{ > + struct blk_desc *desc = dev_get_uclass_plat(blk); > + struct disk_partition partition; > + char partname[PART_NAME_LEN]; > + ulong num_blks, bufsz; > + char *buf; > + int ret; > + > + sprintf(partname, BOOT_PART_NAME "_%s", priv->slot); > + ret = part_get_info_by_name(desc, partname, &partition); > + if (ret < 0) > + return log_msg_ret("part info", ret); > + > + num_blks = DIV_ROUND_UP(sizeof(struct andr_boot_img_hdr_v0), > desc->blksz); > + bufsz = num_blks * desc->blksz; > + buf = malloc(bufsz); > + if (!buf) > + return log_msg_ret("buf", -ENOMEM); > + > + ret = blk_read(blk, partition.start, num_blks, buf); > + if (ret != num_blks) { > + free(buf); > + return log_msg_ret("part read", -EIO); > + } > + > + if (!is_android_boot_image_header(buf)) { > + free(buf); > + return log_msg_ret("header", -ENOENT); > + } > + > + priv->header_version = ((struct andr_boot_img_hdr_v0 > *)buf)->header_version; > + free(buf); > + > + return 0; > +} > + > +static int scan_vendor_boot_part(struct udevice *blk, struct android_priv > *priv) > +{ > + struct blk_desc *desc = dev_get_uclass_plat(blk); > + struct disk_partition partition; > + char partname[PART_NAME_LEN]; > + ulong num_blks, bufsz; > + char *buf; > + int ret; > + > + sprintf(partname, VENDOR_BOOT_PART_NAME "_%s", priv->slot); > + ret = part_get_info_by_name(desc, partname, &partition); > + if (ret < 0) > + return log_msg_ret("part info", ret); > + > + num_blks = DIV_ROUND_UP(sizeof(struct andr_vnd_boot_img_hdr), > desc->blksz); > + bufsz = num_blks * desc->blksz; > + buf = malloc(bufsz); > + if (!buf) > + return log_msg_ret("buf", -ENOMEM); > + > + ret = blk_read(blk, partition.start, num_blks, buf); > + if (ret != num_blks) { > + free(buf); > + return log_msg_ret("part read", -EIO); > + } > + > + if (!is_android_vendor_boot_image_header(buf)) { > + free(buf); > + return log_msg_ret("header", -ENOENT); > + } > + free(buf); > + > + return 0; > +} > + > +static int android_read_slot_from_bcb(struct bootflow *bflow, bool decrement) > +{ > + struct blk_desc *desc = dev_get_uclass_plat(bflow->blk); > + struct android_priv *priv = bflow->bootmeth_priv; > + struct disk_partition misc; > + char slot_suffix[3]; > + int ret; > + > + ret = part_get_info_by_name(desc, BCB_PART_NAME, &misc); > + if (ret < 0) > + return log_msg_ret("part", ret); > + > + ret = ab_select_slot(desc, &misc, decrement); > + if (ret < 0) > + return log_msg_ret("slot", ret); > + > + priv->slot[0] = BOOT_SLOT_NAME(ret); > + priv->slot[1] = '\0'; > + > + sprintf(slot_suffix, "_%s", priv->slot); > + ret = bootflow_cmdline_set_arg(bflow, "androidboot.slot_suffix", > + slot_suffix, false); > + if (ret < 0) > + return log_msg_ret("cmdl", ret); > + > + return 0; > +} > + > +static int configure_serialno(struct bootflow *bflow) > +{ > + char *serialno = env_get("serial#"); > + > + if (!serialno) > + return log_msg_ret("serial", -ENOENT); > + > + return bootflow_cmdline_set_arg(bflow, "androidboot.serialno", > serialno, false); > +} > + > +static int android_read_bootflow(struct udevice *dev, struct bootflow *bflow) > +{ > + struct blk_desc *desc = dev_get_uclass_plat(bflow->blk); > + struct disk_partition misc; > + struct android_priv *priv; > + char command[BCB_FIELD_COMMAND_SZ]; > + int ret; > + > + bflow->state = BOOTFLOWST_MEDIA; > + > + /* > + * bcb_find_partition_and_load() will print errors to stdout > + * if BCB_PART_NAME is not found. To avoid that, check if the > + * partition exists first. > + */ > + ret = part_get_info_by_name(desc, BCB_PART_NAME, &misc); > + if (ret < 0) > + return log_msg_ret("part", ret); > + > + ret = bcb_find_partition_and_load("mmc", desc->devnum, BCB_PART_NAME); > + if (ret < 0) > + return log_msg_ret("bcb load", ret); > + > + ret = bcb_get(BCB_FIELD_COMMAND, command, sizeof(command)); > + if (ret < 0) > + return log_msg_ret("bcb read", ret); > + > + priv = malloc(sizeof(struct android_priv)); > + if (!priv) > + return log_msg_ret("buf", -ENOMEM); > + > + if (!strcmp("bootonce-bootloader", command)) { > + priv->boot_mode = ANDROID_BOOT_MODE_BOOTLOADER; > + bflow->os_name = strdup("Android (bootloader)"); > + } else if (!strcmp("boot-fastboot", command)) { > + priv->boot_mode = ANDROID_BOOT_MODE_RECOVERY; > + bflow->os_name = strdup("Android (fastbootd)"); > + } else if (!strcmp("boot-recovery", command)) { > + priv->boot_mode = ANDROID_BOOT_MODE_RECOVERY; > + bflow->os_name = strdup("Android (recovery)"); > + } else { > + priv->boot_mode = ANDROID_BOOT_MODE_NORMAL; > + bflow->os_name = strdup("Android"); > + } > + if (!bflow->os_name) > + return log_msg_ret("os", -ENOMEM); > + > + if (priv->boot_mode == ANDROID_BOOT_MODE_BOOTLOADER) { > + /* Clear BCB */ > + memset(command, 0, sizeof(command)); > + ret = bcb_set(BCB_FIELD_COMMAND, command); > + if (ret < 0) { > + free(priv); > + return log_msg_ret("bcb set", ret); > + } > + ret = bcb_store(); > + if (ret < 0) { > + free(priv); > + return log_msg_ret("bcb store", ret); > + } > + > + bflow->bootmeth_priv = priv; > + bflow->state = BOOTFLOWST_READY; > + return 0; > + } > + > + bflow->bootmeth_priv = priv; > + > + /* For recovery and normal boot, we need to scan the partitions */ > + ret = android_read_slot_from_bcb(bflow, false); > + if (ret < 0) { > + log_err("read slot: %d", ret); > + goto free_priv; > + } > + > + ret = scan_boot_part(bflow->blk, priv); > + if (ret < 0) { > + log_debug("scan boot failed: err=%d\n", ret); > + goto free_priv; > + } > + > + if (priv->header_version != 4) { > + log_debug("only boot.img v4 is supported %u\n", > priv->header_version); > + ret = -EINVAL; > + goto free_priv; > + } > + > + ret = scan_vendor_boot_part(bflow->blk, priv); > + if (ret < 0) { > + log_debug("scan vendor_boot failed: err=%d\n", ret); > + goto free_priv; > + } > + > + /* Ignoring return code: setting serial number is not mandatory for > booting */ > + configure_serialno(bflow); > + > + if (priv->boot_mode == ANDROID_BOOT_MODE_NORMAL) { > + ret = bootflow_cmdline_set_arg(bflow, > "androidboot.force_normal_boot", > + "1", false); > + if (ret < 0) { > + log_debug("normal_boot %d", ret); > + goto free_priv; > + } > + } > + > + bflow->state = BOOTFLOWST_READY; > + > + return 0; > + > + free_priv: > + free(priv); > + bflow->bootmeth_priv = NULL; > + return ret; > +} > + > +static int android_read_file(struct udevice *dev, struct bootflow *bflow, > + const char *file_path, ulong addr, ulong *sizep) > +{ > + /* > + * Reading individual files is not supported since we only > + * operate on whole mmc devices (because we require multiple partitions) > + */ > + return log_msg_ret("Unsupported", -ENOSYS); > +} > + > +/** > + * read_slotted_partition() - Read a partition by appending a slot suffix > + * > + * Most modern Android devices use Seamless Updates, where each partition > + * is duplicated. For example, the boot partition has boot_a and boot_b. > + * For more information, see: > + * https://source.android.com/docs/core/ota/ab > + * https://source.android.com/docs/core/ota/ab/ab_implement > + * > + * @blk: Block device to read > + * @name: Partition name to read > + * @slot: Nul-terminated slot suffixed to partition name ("a\0" or "b\0") > + * @addr: Address where the partition content is loaded into > + * Return: 0 if OK, negative errno on failure. > + */ > +static int read_slotted_partition(struct blk_desc *desc, const char *const > name, > + const char slot[2], ulong addr) > +{ > + struct disk_partition partition; > + char partname[PART_NAME_LEN]; > + int ret; > + u32 n; > + > + /* Ensure name fits in partname it should be: <name>_<slot>\0 */ > + if (strlen(name) > (PART_NAME_LEN - 2 - 1)) > + return log_msg_ret("name too long", -EINVAL); > + > + sprintf(partname, "%s_%s", name, slot); > + ret = part_get_info_by_name(desc, partname, &partition); > + if (ret < 0) > + return log_msg_ret("part", ret); > + > + n = blk_dread(desc, partition.start, partition.size, map_sysmem(addr, > 0)); > + if (n < partition.size) > + return log_msg_ret("part read", -EIO); > + > + return 0; > +} > + > +#if CONFIG_IS_ENABLED(AVB_VERIFY) > +static int avb_append_commandline_arg(struct bootflow *bflow, char *arg) > +{ > + char *key = strsep(&arg, "="); > + char *value = arg; > + int ret; > + > + ret = bootflow_cmdline_set_arg(bflow, key, value, false); > + if (ret < 0) > + return log_msg_ret("avb cmdline", ret); > + > + return 0; > +} > + > +static int avb_append_commandline(struct bootflow *bflow, char *cmdline) > +{ > + char *arg = strsep(&cmdline, " "); > + int ret; > + > + while (arg) { > + ret = avb_append_commandline_arg(bflow, arg); > + if (ret < 0) > + return ret; > + > + arg = strsep(&cmdline, " "); > + } > + > + return 0; > +} > + > +static int run_avb_verification(struct bootflow *bflow) > +{ > + struct blk_desc *desc = dev_get_uclass_plat(bflow->blk); > + struct android_priv *priv = bflow->bootmeth_priv; > + const char * const requested_partitions[] = {"boot", "vendor_boot"}; > + struct AvbOps *avb_ops; > + AvbSlotVerifyResult result; > + AvbSlotVerifyData *out_data; > + enum avb_boot_state boot_state; > + char *extra_args; > + char slot_suffix[3]; > + bool unlocked = false; > + int ret; > + > + avb_ops = avb_ops_alloc(desc->devnum); > + if (!avb_ops) > + return log_msg_ret("avb ops", -ENOMEM); > + > + sprintf(slot_suffix, "_%s", priv->slot); > + > + ret = avb_ops->read_is_device_unlocked(avb_ops, &unlocked); > + if (ret != AVB_IO_RESULT_OK) > + return log_msg_ret("avb lock", -EIO); > + > + result = avb_slot_verify(avb_ops, > + requested_partitions, > + slot_suffix, > + unlocked, > + AVB_HASHTREE_ERROR_MODE_RESTART_AND_INVALIDATE, > + &out_data); > + > + if (result != AVB_SLOT_VERIFY_RESULT_OK) { > + printf("Verification failed, reason: %s\n", > + str_avb_slot_error(result)); > + avb_slot_verify_data_free(out_data); > + return log_msg_ret("avb verify", -EIO); > + } > + > + if (unlocked) > + boot_state = AVB_ORANGE; > + else > + boot_state = AVB_GREEN; > + > + extra_args = avb_set_state(avb_ops, boot_state); > + if (extra_args) { > + /* extra_args will be modified after this. This is fine */ > + ret = avb_append_commandline_arg(bflow, extra_args); > + if (ret < 0) > + goto free_out_data; > + } > + > + ret = avb_append_commandline(bflow, out_data->cmdline); > + if (ret < 0) > + goto free_out_data; > + > + return 0; > + > + free_out_data: > + if (out_data) > + avb_slot_verify_data_free(out_data); > + > + return log_msg_ret("avb cmdline", ret); > +} > +#else > +static int run_avb_verification(struct bootflow *bflow) > +{ > + int ret; > + > + /* When AVB is unsupported, pass ORANGE state */ > + ret = bootflow_cmdline_set_arg(bflow, > + "androidboot.verifiedbootstate", > + "orange", false); > + if (ret < 0) > + return log_msg_ret("avb cmdline", ret); > + > + return 0; > +} > +#endif /* AVB_VERIFY */ > + > +static int boot_android_normal(struct bootflow *bflow) > +{ > + struct blk_desc *desc = dev_get_uclass_plat(bflow->blk); > + struct android_priv *priv = bflow->bootmeth_priv; > + int ret; > + ulong loadaddr = env_get_hex("loadaddr", 0); > + ulong vloadaddr = env_get_hex("vendor_boot_comp_addr_r", 0); > + > + ret = run_avb_verification(bflow); > + if (ret < 0) > + return log_msg_ret("avb", ret); > + > + /* Read slot once more to decrement counter from BCB */ > + ret = android_read_slot_from_bcb(bflow, true); > + if (ret < 0) > + return log_msg_ret("read slot", ret); > + > + ret = read_slotted_partition(desc, "boot", priv->slot, loadaddr); > + if (ret < 0) > + return log_msg_ret("read boot", ret); > + > + ret = read_slotted_partition(desc, "vendor_boot", priv->slot, > vloadaddr); > + if (ret < 0) > + return log_msg_ret("read vendor_boot", ret); > + > + set_abootimg_addr(loadaddr); > + set_avendor_bootimg_addr(vloadaddr); > + > + ret = bootm_boot_start(loadaddr, bflow->cmdline); > + > + return log_msg_ret("boot", ret); > +} > + > +static int boot_android_recovery(struct bootflow *bflow) > +{ > + int ret; > + > + ret = boot_android_normal(bflow); > + > + return log_msg_ret("boot", ret); > +} > + > +static int boot_android_bootloader(struct bootflow *bflow) > +{ > + int ret; > + > + ret = run_command("fastboot usb 0", 0); > + do_reset(NULL, 0, 0, NULL); > + > + return log_msg_ret("boot", ret); > +} > + > +static int android_boot(struct udevice *dev, struct bootflow *bflow) > +{ > + struct android_priv *priv = bflow->bootmeth_priv; > + int ret; > + > + switch (priv->boot_mode) { > + case ANDROID_BOOT_MODE_NORMAL: > + ret = boot_android_normal(bflow); > + break; > + case ANDROID_BOOT_MODE_RECOVERY: > + ret = boot_android_recovery(bflow); > + break; > + case ANDROID_BOOT_MODE_BOOTLOADER: > + ret = boot_android_bootloader(bflow); > + break; > + default: > + printf("ANDROID: Unknown boot mode %d. Running fastboot...\n", > + priv->boot_mode); > + boot_android_bootloader(bflow); > + /* Tell we failed to boot since boot mode is unknown */ > + ret = -EFAULT; > + } > + > + return ret; > +} > + > +static int android_bootmeth_bind(struct udevice *dev) > +{ > + struct bootmeth_uc_plat *plat = dev_get_uclass_plat(dev); > + > + plat->desc = "Android boot"; > + plat->flags = BOOTMETHF_ANY_PART; > + > + return 0; > +} > + > +static struct bootmeth_ops android_bootmeth_ops = { > + .check = android_check, > + .read_bootflow = android_read_bootflow, > + .read_file = android_read_file, > + .boot = android_boot, > +}; > + > +static const struct udevice_id android_bootmeth_ids[] = { > + { .compatible = "u-boot,android" }, > + { } > +}; > + > +U_BOOT_DRIVER(bootmeth_android) = { > + .name = "bootmeth_android", > + .id = UCLASS_BOOTMETH, > + .of_match = android_bootmeth_ids, > + .ops = &android_bootmeth_ops, > + .bind = android_bootmeth_bind, > +}; > diff --git a/boot/bootmeth_android.h b/boot/bootmeth_android.h > new file mode 100644 > index 000000000000..a57fad9f0113 > --- /dev/null > +++ b/boot/bootmeth_android.h > @@ -0,0 +1,29 @@ > +/* SPDX-License-Identifier: GPL-2.0+ */ > +/* > + * Bootmethod for Android > + * > + * Copyright (C) 2024 BayLibre, SAS > + * Written by Mattijs Korpershoek <mkorpersh...@baylibre.com> > + */ > + > +enum android_boot_mode { > + ANDROID_BOOT_MODE_NORMAL = 0, > + > + /* > + * Android "recovery" is a special boot mode that uses another ramdisk. > + * It can be used to "factory reset" a board or to flash logical > partitions > + * It operates in 2 modes: adb or fastbootd > + * To enter recovery from Android, we can do: > + * $ adb reboot recovery > + * $ adb reboot fastboot > + */ > + ANDROID_BOOT_MODE_RECOVERY, > + > + /* > + * Android "bootloader" is for accessing/reflashing physical partitions > + * Typically, this will launch a fastboot process in U-Boot. > + * To enter "bootloader" from Android, we can do: > + * $ adb reboot bootloader > + */ > + ANDROID_BOOT_MODE_BOOTLOADER, > +}; > diff --git a/doc/develop/bootstd.rst b/doc/develop/bootstd.rst > index a07a72581e7a..709fa9e64ff3 100644 > --- a/doc/develop/bootstd.rst > +++ b/doc/develop/bootstd.rst > @@ -95,6 +95,7 @@ bootflows. > > Note: it is possible to have a bootmeth that uses a partition or a whole > device > directly, but it is more common to use a filesystem. > +For example, the Android bootmeth uses a whole device. > > Note that some bootmeths are 'global', meaning that they select the bootdev > themselves. Examples include VBE and EFI boot manager. In this case, they > @@ -277,6 +278,9 @@ script_offset_f > script_size_f > Size of the script to load, e.g. 0x2000 > > +vendor_boot_comp_addr_r > + Address to which to load the vendor_boot Android image, e.g. 0xe0000000 > + > Some variables are set by script bootmeth: > > devtype > @@ -418,6 +422,7 @@ Bootmeth drivers are provided for: > - EFI boot using bootefi from disk > - VBE > - EFI boot using boot manager > + - Android bootflow (boot image v4) > > > Command interface > @@ -786,6 +791,7 @@ To do > Some things that need to be done to completely replace the distro-boot > scripts: > > - implement extensions (devicetree overlays with add-on boards) > +- implement legacy (boot image v2) android boot flow > > Other ideas: > > > -- > 2.45.2 > Reviewed-by: Julien Masson <jmas...@baylibre.com> -- Julien Masson
