GPT: add accessor function for disk GUID

[people/ms/u-boot.git] / disk / part_efi.c

diff --git a/disk/part_efi.c b/disk/part_efi.c
index 20d33ef275ffe7618277b33dde051e1a7671bf08..71c3cb3f78d9fbffae660c019cfa54d3bb4ef7e1 100644 (file)
--- a/disk/part_efi.c
+++ b/disk/part_efi.c
@@ -178,6 +178,37 @@ static void prepare_backup_gpt_header(gpt_header *gpt_h)
  * Public Functions (include/part.h)
  */
 
+/*
+ * UUID is displayed as 32 hexadecimal digits, in 5 groups,
+ * separated by hyphens, in the form 8-4-4-4-12 for a total of 36 characters
+ */
+int get_disk_guid(struct blk_desc * dev_desc, char *guid)
+{
+       ALLOC_CACHE_ALIGN_BUFFER_PAD(gpt_header, gpt_head, 1, dev_desc->blksz);
+       gpt_entry *gpt_pte = NULL;
+       unsigned char *guid_bin;
+
+       /* This function validates AND fills in the GPT header and PTE */
+       if (is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA,
+                        gpt_head, &gpt_pte) != 1) {
+               printf("%s: *** ERROR: Invalid GPT ***\n", __func__);
+               if (is_gpt_valid(dev_desc, dev_desc->lba - 1,
+                                gpt_head, &gpt_pte) != 1) {
+                       printf("%s: *** ERROR: Invalid Backup GPT ***\n",
+                              __func__);
+                       return -EINVAL;
+               } else {
+                       printf("%s: ***        Using Backup GPT ***\n",
+                              __func__);
+               }
+       }
+
+       guid_bin = gpt_head->disk_guid.b;
+       uuid_bin_to_str(guid_bin, guid, UUID_STR_FORMAT_GUID);
+
+       return 0;
+}
+
 void part_print_efi(struct blk_desc *dev_desc)
 {
        ALLOC_CACHE_ALIGN_BUFFER_PAD(gpt_header, gpt_head, 1, dev_desc->blksz);