2 * This is from the Android Project,
3 * Repository: https://android.googlesource.com/platform/bootable/recovery
4 * File: bootloader_message/include/bootloader_message/bootloader_message.h
5 * Commit: See U-Boot commit description
7 * Copyright (C) 2008 The Android Open Source Project
9 * SPDX-License-Identifier: BSD-3-Clause
12 #ifndef __ANDROID_BOOTLOADER_MESSAGE_H
13 #define __ANDROID_BOOTLOADER_MESSAGE_H
20 /* compiler.h defines the types that otherwise are included from stdint.h and
26 // Spaces used by misc partition are as below:
27 // 0 - 2K For bootloader_message
28 // 2K - 16K Used by Vendor's bootloader (the 2K - 4K range may be optionally used
29 // as bootloader_message_ab struct)
30 // 16K - 64K Used by uncrypt and recovery to store wipe_package for A/B devices
31 // Note that these offsets are admitted by bootloader,recovery and uncrypt, so they
32 // are not configurable without changing all of them.
33 static const size_t BOOTLOADER_MESSAGE_OFFSET_IN_MISC
= 0;
34 static const size_t WIPE_PACKAGE_OFFSET_IN_MISC
= 16 * 1024;
36 /* Bootloader Message (2-KiB)
38 * This structure describes the content of a block in flash
39 * that is used for recovery and the bootloader to talk to
42 * The command field is updated by linux when it wants to
43 * reboot into recovery or to update radio or bootloader firmware.
44 * It is also updated by the bootloader when firmware update
45 * is complete (to boot into recovery for any final cleanup)
47 * The status field was used by the bootloader after the completion
48 * of an "update-radio" or "update-hboot" command, which has been
49 * deprecated since Froyo.
51 * The recovery field is only written by linux and used
52 * for the system to send a message to recovery or the
55 * The stage field is written by packages which restart themselves
56 * multiple times, so that the UI can reflect which invocation of the
57 * package it is. If the value is of the format "#/#" (eg, "1/3"),
58 * the UI will add a simple indicator of that status.
60 * We used to have slot_suffix field for A/B boot control metadata in
61 * this struct, which gets unintentionally cleared by recovery or
62 * uncrypt. Move it into struct bootloader_message_ab to avoid the
65 struct bootloader_message
{
70 // The 'recovery' field used to be 1024 bytes. It has only ever
71 // been used to store the recovery command line, so 768 bytes
72 // should be plenty. We carve off the last 256 bytes to store the
73 // stage string (for multistage packages) and possible future
77 // The 'reserved' field used to be 224 bytes when it was initially
78 // carved off from the 1024-byte recovery field. Bump it up to
79 // 1184-byte so that the entire bootloader_message struct rounds up
85 * We must be cautious when changing the bootloader_message struct size,
86 * because A/B-specific fields may end up with different offsets.
89 #if (__STDC_VERSION__ >= 201112L) || defined(__cplusplus)
90 static_assert(sizeof(struct bootloader_message
) == 2048,
91 "struct bootloader_message size changes, which may break A/B devices");
93 #endif /* __UBOOT__ */
96 * The A/B-specific bootloader message structure (4-KiB).
98 * We separate A/B boot control metadata from the regular bootloader
99 * message struct and keep it here. Everything that's A/B-specific
100 * stays after struct bootloader_message, which should be managed by
101 * the A/B-bootloader or boot control HAL.
103 * The slot_suffix field is used for A/B implementations where the
104 * bootloader does not set the androidboot.ro.boot.slot_suffix kernel
105 * commandline parameter. This is used by fs_mgr to mount /system and
106 * other partitions with the slotselect flag set in fstab. A/B
107 * implementations are free to use all 32 bytes and may store private
108 * data past the first NUL-byte in this field. It is encouraged, but
109 * not mandatory, to use 'struct bootloader_control' described below.
111 * The update_channel field is used to store the Omaha update channel
112 * if update_engine is compiled with Omaha support.
114 struct bootloader_message_ab
{
115 struct bootloader_message message
;
116 char slot_suffix
[32];
117 char update_channel
[128];
119 // Round up the entire struct to 4096-byte.
124 * Be cautious about the struct size change, in case we put anything post
125 * bootloader_message_ab struct (b/29159185).
128 #if (__STDC_VERSION__ >= 201112L) || defined(__cplusplus)
129 static_assert(sizeof(struct bootloader_message_ab
) == 4096,
130 "struct bootloader_message_ab size changes");
132 #endif /* __UBOOT__ */
134 #define BOOT_CTRL_MAGIC 0x42414342 /* Bootloader Control AB */
135 #define BOOT_CTRL_VERSION 1
137 struct slot_metadata
{
138 // Slot priority with 15 meaning highest priority, 1 lowest
139 // priority and 0 the slot is unbootable.
140 uint8_t priority
: 4;
141 // Number of times left attempting to boot this slot.
142 uint8_t tries_remaining
: 3;
143 // 1 if this slot has booted successfully, 0 otherwise.
144 uint8_t successful_boot
: 1;
145 // 1 if this slot is corrupted from a dm-verity corruption, 0
147 uint8_t verity_corrupted
: 1;
148 // Reserved for further use.
149 uint8_t reserved
: 7;
150 } __attribute__((packed
));
152 /* Bootloader Control AB
154 * This struct can be used to manage A/B metadata. It is designed to
155 * be put in the 'slot_suffix' field of the 'bootloader_message'
156 * structure described above. It is encouraged to use the
157 * 'bootloader_control' structure to store the A/B metadata, but not
160 struct bootloader_control
{
161 // NUL terminated active slot suffix.
163 // Bootloader Control AB magic number (see BOOT_CTRL_MAGIC).
165 // Version of struct being used (see BOOT_CTRL_VERSION).
167 // Number of slots being managed.
169 // Number of times left attempting to boot recovery.
170 uint8_t recovery_tries_remaining
: 3;
171 // Ensure 4-bytes alignment for slot_info field.
172 uint8_t reserved0
[2];
173 // Per-slot information. Up to 4 slots.
174 struct slot_metadata slot_info
[4];
175 // Reserved for further use.
176 uint8_t reserved1
[8];
177 // CRC32 of all 28 bytes preceding this field (little endian
180 } __attribute__((packed
));
183 #if (__STDC_VERSION__ >= 201112L) || defined(__cplusplus)
184 static_assert(sizeof(struct bootloader_control
) ==
185 sizeof(((struct bootloader_message_ab
*)0)->slot_suffix
),
186 "struct bootloader_control has wrong size");
188 #endif /* __UBOOT__ */
196 // Return the block device name for the bootloader message partition and waits
197 // for the device for up to 10 seconds. In case of error returns the empty
199 std::string
get_bootloader_message_blk_device(std::string
* err
);
201 // Read bootloader message into boot. Error message will be set in err.
202 bool read_bootloader_message(bootloader_message
* boot
, std::string
* err
);
204 // Read bootloader message from the specified misc device into boot.
205 bool read_bootloader_message_from(bootloader_message
* boot
, const std::string
& misc_blk_device
,
208 // Write bootloader message to BCB.
209 bool write_bootloader_message(const bootloader_message
& boot
, std::string
* err
);
211 // Write bootloader message to the specified BCB device.
212 bool write_bootloader_message_to(const bootloader_message
& boot
,
213 const std::string
& misc_blk_device
, std::string
* err
);
215 // Write bootloader message (boots into recovery with the options) to BCB. Will
216 // set the command and recovery fields, and reset the rest.
217 bool write_bootloader_message(const std::vector
<std::string
>& options
, std::string
* err
);
219 // Write bootloader message (boots into recovery with the options) to the specific BCB device. Will
220 // set the command and recovery fields, and reset the rest.
221 bool write_bootloader_message_to(const std::vector
<std::string
>& options
,
222 const std::string
& misc_blk_device
, std::string
* err
);
224 // Update bootloader message (boots into recovery with the options) to BCB. Will
225 // only update the command and recovery fields.
226 bool update_bootloader_message(const std::vector
<std::string
>& options
, std::string
* err
);
228 // Update bootloader message (boots into recovery with the |options|) in |boot|. Will only update
229 // the command and recovery fields.
230 bool update_bootloader_message_in_struct(bootloader_message
* boot
,
231 const std::vector
<std::string
>& options
);
234 bool clear_bootloader_message(std::string
* err
);
236 // Writes the reboot-bootloader reboot reason to the bootloader_message.
237 bool write_reboot_bootloader(std::string
* err
);
239 // Read the wipe package from BCB (from offset WIPE_PACKAGE_OFFSET_IN_MISC).
240 bool read_wipe_package(std::string
* package_data
, size_t size
, std::string
* err
);
242 // Write the wipe package into BCB (to offset WIPE_PACKAGE_OFFSET_IN_MISC).
243 bool write_wipe_package(const std::string
& package_data
, std::string
* err
);
250 bool write_bootloader_message(const char* options
);
251 bool write_reboot_bootloader(void);
253 #endif // ifdef __cplusplus
254 #endif /* __UBOOT__ */
256 #endif /* __ANDROID_BOOTLOADER_MESSAGE_H */