disk: expose partition type flags

GPT partition tables include two bytes worth of vendor defined
attributes, per partition. ChromeOS and Qualcomm both use these (with
different encoding!) to handle A/B slot switching with a retry counter.

Expose these via the disk_partition struct so that they can be parsed by
the relevant board code.

This will be used on Qualcomm boards to determine which slot we're
booting on so that we can flash capsule updates to the correct one.

Reviewed-by: Ilias Apalodimas <[email protected]>
Reviewed-by: Mattijs Korpershoek <[email protected]>
Signed-off-by: Caleb Connolly <[email protected]>

Author: calebccff

disk/part_efi.c

@@ -292,6 +292,7 @@ static int __maybe_unused part_get_info_efi(struct blk_desc *desc, int part,
 		 print_efiname(&gpt_pte[part - 1]));
 	strcpy((char *)info->type, "U-Boot");
 	info->bootable = get_bootable(&gpt_pte[part - 1]);
+	info->type_flags = gpt_pte[part - 1].attributes.fields.type_guid_specific;
 	if (CONFIG_IS_ENABLED(PARTITION_UUIDS)) {
 		uuid_bin_to_str(gpt_pte[part - 1].unique_partition_guid.b,
 				(char *)disk_partition_uuid(info),

include/part.h

@@ -74,6 +74,7 @@ struct disk_partition {
 	 * PART_EFI_SYSTEM_PARTITION	the partition is an EFI system partition
 	 */
 	int	bootable;
+	u16	type_flags;	/* top 16 bits of GPT partition attributes	*/
 #if CONFIG_IS_ENABLED(PARTITION_UUIDS)
 	char	uuid[UUID_STR_LEN + 1];	/* filesystem UUID as string, if exists	*/
 #endif