image: android: Add routine to get dtbo params

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>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
This commit is contained in:
Sam Protsenko 2020-01-24 17:53:41 +02:00 committed by Lokesh Vutla
parent c3bfad825a
commit 7f2531502c
2 changed files with 62 additions and 0 deletions

View file

@ -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

View file

@ -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);