Hi Simon, Thank you for your review.
On mar., juin 11, 2024 at 12:52, Simon Glass <s...@chromium.org> wrote: > Hi Mattijs, > > On Thu, 6 Jun 2024 at 06:24, 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/ >> >> Signed-off-by: Mattijs Korpershoek <mkorpersh...@baylibre.com> >> --- >> MAINTAINERS | 7 + >> boot/Kconfig | 14 ++ >> boot/Makefile | 2 + >> boot/bootmeth_android.c | 522 >> ++++++++++++++++++++++++++++++++++++++++++++++++ >> boot/bootmeth_android.h | 27 +++ >> doc/develop/bootstd.rst | 6 + >> 6 files changed, 578 insertions(+) > > Reviewed-by: Simon Glass <s...@chromium.org> > > nits below > >> >> 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 Behún <ka...@kernel.org> >> R: Qu Wenruo <w...@suse.com> >> diff --git a/boot/Kconfig b/boot/Kconfig >> index 6f3096c15a6f..5fa6f3b8315d 100644 >> --- a/boot/Kconfig >> +++ b/boot/Kconfig >> @@ -494,6 +494,20 @@ 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 PARTITION_TYPE_GUID >> + select PARTITION_UUIDS >> + help >> + Enables support for booting Android using bootdevs. Android >> requires > > using standard boot (or using bootstd). Will do for v2. > >> + multiple partitions (misc, boot, vbmeta, ...) in storage for >> booting. >> + >> + Note that only MMC bootdevs are supported at present. > > Why is that limitation present? Can you please mention what is needed > to remove it? Mainly because we use AVB and AVB is hard-coded for MMC. Alistair submitted changes to convert to generic block devices here: https://lore.kernel.org/all/20220926220211.868968-1-ade...@google.com/ There were some review comments but I did not see any v2 on the list. I will add a comment in the KConfig description. > >> + >> 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..26d548d2fd6e >> --- /dev/null >> +++ b/boot/bootmeth_android.c >> @@ -0,0 +1,522 @@ >> +// SPDX-License-Identifier: GPL-2.0+ >> +/* >> + * Bootmethod for Android > > This is my fault, but I think we should settle on Bootmeth throughout. Yes, thank you for noticing. Will do for v2. > >> + * >> + * 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> > > Can you include that header always? I can't, it does not link if I do. It would be possible if we implemented stub functions but that's not the case today. Since this is a nitpick, I will consider this for a future improvement. > >> +#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 > > please add member comments as I don't know what these fields are Will do for v2. > >> + */ >> +struct android_priv { >> + int 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 = android_image_get_version(buf); >> + >> + return 0; >> +} >> + >> +static int scan_vendor_boot_part(struct udevice *blk, const char slot[2]) >> +{ >> + 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", 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); >> + } >> + >> + 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("slot", ret); > > perhaps "cmdl" ? Yes, will do for v2. > >> + >> + 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 > > I believe this first line should just be /* You are right. I've made this mistake in other parts of the file. Will fix all occurences for v2. > >> + * 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); >> + >> + bflow->bootmeth_priv = priv; > > ideally this would happen at the end of the function Yes, Igor pointed out as well. It's dangerous to have a dangling pointer. Will do for v2. > >> + 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->state = BOOTFLOWST_READY; >> + return 0; >> + } >> + >> + /* For recovery and normal boot, we need to scan the partitions */ >> + ret = android_read_slot_from_bcb(bflow, false); >> + if (ret < 0) { >> + free(priv); >> + return log_msg_ret("read slot", ret); >> + } >> + >> + ret = scan_boot_part(bflow->blk, priv); >> + if (ret < 0) { >> + printf("- scan boot failed: err=%d\n", ret); >> + free(priv); >> + return log_msg_ret("scan boot", ret); >> + } >> + >> + if (priv->header_version != 4) { >> + printf("- Only boot.img v4 is supported\n"); > > shouldn't this be log_debug() ? Hmm, I've modeled this to be similar to bootmeth_cros, but I can convert to log_debug(). I don't have a strong opinion on this. > >> + free(priv); >> + return log_msg_ret("version", -EINVAL); >> + } >> + >> + ret = scan_vendor_boot_part(bflow->blk, priv->slot); >> + if (ret < 0) { >> + printf("- scan vendor_boot failed: err=%d\n", ret); >> + free(priv); >> + return log_msg_ret("scan vendor_boot", ret); >> + } >> + >> + /* 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); > > check line length Yes, somehow I missed this with checkpatch. Will fix for v2. > >> + if (ret < 0) { >> + free(priv); >> + return log_msg_ret("normal_boot", ret); >> + } >> + } >> + >> + bflow->state = BOOTFLOWST_READY; >> + >> + return 0; >> +} >> + >> +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); >> +} >> + >> +static int read_slotted_partition(struct blk_desc *desc, const char *const >> name, >> + const char slot[2], ulong addr) > > What is a slotted partition? This function could use a comment Most modern Android devices use "Seamless updates", where each partition is duplicated. For example, the boot partition has boot_a and boot_b. This is what I called "slotted partition". See: https://source.android.com/docs/core/ota/ab https://source.android.com/docs/core/ota/ab/ab_implement I will add a comment pointing to the above documentation and some additional explanation in v2. > >> +{ >> + 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) > > Can you use if() instead, and either rename the functions below or add > this if() to each function? I will try, but most avb_ops related functions are not stubbed so I'm not sure we can do this easily. Since this is a nitpick, I might consider this a future improvement (If stubs are needed, for example). > >> +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)); >> + 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) { >> + ret = avb_append_commandline_arg(bflow, extra_args); > > This function will write to extra_args...is that OK? Yes, extra_args is no longer used after this. I will add a comment to state that this is safe in v2. > >> + 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; >> + > > drop blank line Will do for v2. > >> + 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..411c2f2d15e7 >> --- /dev/null >> +++ b/boot/bootmeth_android.h >> @@ -0,0 +1,27 @@ >> +/* 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 > > Nice! Thank you! It was easier to implement that I imagined, mainly because the bootflow framework is well written (imo) and the bootmeth_cros example was very helpful as well. > >> >> Other ideas: >> >> >> -- >> 2.45.0 >> > > Regards, > Simon
