Android Boot Image v1 adds "Recovery DTB" field in image header and associate payload in boot image itself [1]. Payload should be in Android DTB/DTBO format [2]. That "Recovery DTB" area should be only populated for non-A/B devices, and only in recovery image.
Add function to get an address and size of that payload. That function can be further used e.g. in 'abootimg' command to provide the user a way to get the address of recovery dtbo from U-Boot shell, which can be further parsed using 'adtimg' command.
[1] https://source.android.com/devices/bootloader/boot-image-header [2] https://source.android.com/devices/architecture/dto/partitions
Signed-off-by: Sam Protsenko joe.skb7@gmail.com --- common/image-android.c | 61 ++++++++++++++++++++++++++++++++++++++++++ include/image.h | 1 + 2 files changed, 62 insertions(+)
diff --git a/common/image-android.c b/common/image-android.c index 220983655a..6af9baa121 100644 --- a/common/image-android.c +++ b/common/image-android.c @@ -197,6 +197,67 @@ int android_image_get_second(const struct andr_img_hdr *hdr, return 0; }
+/** + * android_image_get_dtbo() - Get address and size of recovery DTBO image. + * @hdr_addr: Boot image header address + * @addr: If not NULL, will contain address of recovery DTBO image + * @size: If not NULL, will contain size of recovery DTBO image + * + * Get the address and size of DTBO image in "Recovery DTBO" area of Android + * Boot Image in RAM. The format of this image is Android DTBO (see + * corresponding "DTB/DTBO Partitions" AOSP documentation for details). Once + * the address is obtained from this function, one can use 'adtimg' U-Boot + * command or android_dt_*() functions to extract desired DTBO blob. + * + * This DTBO (included in boot image) is only needed for non-A/B devices, and it + * only can be found in recovery image. On A/B devices we can always rely on + * "dtbo" partition. See "Including DTBO in Recovery for Non-A/B Devices" in + * AOSP documentation for details. + * + * Return: true on success or false on error. + */ +bool android_image_get_dtbo(ulong hdr_addr, ulong *addr, u32 *size) +{ + const struct andr_img_hdr *hdr; + ulong dtbo_img_addr; + bool ret = true; + + hdr = map_sysmem(hdr_addr, sizeof(*hdr)); + if (android_image_check_header(hdr)) { + printf("Error: Boot Image header is incorrect\n"); + ret = false; + goto exit; + } + + if (hdr->header_version < 1) { + printf("Error: header_version must be >= 1 to get dtbo\n"); + ret = false; + goto exit; + } + + if (hdr->recovery_dtbo_size == 0) { + printf("Error: recovery_dtbo_size is 0\n"); + ret = false; + goto exit; + } + + /* Calculate the address of DTB area in boot image */ + dtbo_img_addr = hdr_addr; + dtbo_img_addr += hdr->page_size; + dtbo_img_addr += ALIGN(hdr->kernel_size, hdr->page_size); + dtbo_img_addr += ALIGN(hdr->ramdisk_size, hdr->page_size); + dtbo_img_addr += ALIGN(hdr->second_size, hdr->page_size); + + if (addr) + *addr = dtbo_img_addr; + if (size) + *size = hdr->recovery_dtbo_size; + +exit: + unmap_sysmem(hdr); + return ret; +} + /** * android_image_get_dtb_img_addr() - Get the address of DTB area in boot image. * @hdr_addr: Boot image header address diff --git a/include/image.h b/include/image.h index 4e36b87f42..b316d167d8 100644 --- a/include/image.h +++ b/include/image.h @@ -1425,6 +1425,7 @@ int android_image_get_ramdisk(const struct andr_img_hdr *hdr, ulong *rd_data, ulong *rd_len); int android_image_get_second(const struct andr_img_hdr *hdr, ulong *second_data, ulong *second_len); +bool android_image_get_dtbo(ulong hdr_addr, ulong *addr, u32 *size); bool android_image_get_dtb_by_index(ulong hdr_addr, u32 index, ulong *addr, u32 *size); ulong android_image_get_end(const struct andr_img_hdr *hdr);