- part_str = strchr(dev_str, ':');
- if (part_str)
- part = (int)simple_strtoul(++part_str, NULL, 16);
-
- ret = get_partition_info(desc, part, info);
- if (ret) {
- printf("** Invalid partition %d, use `dev[:part]' **\n", part);
- return -1;
+ /*
+ * Now there's known to be a partition table,
+ * not specifying a partition means to pick partition 1.
+ */
+ if (part == PART_UNSPECIFIED)
+ part = 1;
+
+ /*
+ * If user didn't specify a partition number, or did specify something
+ * other than "auto", use that partition number directly.
+ */
+ if (part != PART_AUTO) {
+ ret = get_partition_info(*dev_desc, part, info);
+ if (ret) {
+ printf("** Invalid partition %d **\n", part);
+ goto cleanup;
+ }
+ } else {
+ /*
+ * Find the first bootable partition.
+ * If none are bootable, fall back to the first valid partition.
+ */
+ part = 0;
+ for (p = 1; p <= MAX_SEARCH_PARTITIONS; p++) {
+ ret = get_partition_info(*dev_desc, p, info);
+ if (ret)
+ continue;
+
+ /*
+ * First valid partition, or new better partition?
+ * If so, save partition ID.
+ */
+ if (!part || info->bootable)
+ part = p;
+
+ /* Best possible partition? Stop searching. */
+ if (info->bootable)
+ break;
+
+ /*
+ * We now need to search further for best possible.
+ * If we what we just queried was the best so far,
+ * save the info since we over-write it next loop.
+ */
+ if (part == p)
+ tmpinfo = *info;
+ }
+ /* If we found any acceptable partition */
+ if (part) {
+ /*
+ * If we searched all possible partition IDs,
+ * return the first valid partition we found.
+ */
+ if (p == MAX_SEARCH_PARTITIONS + 1)
+ *info = tmpinfo;
+ ret = 0;
+ } else {
+ printf("** No valid partitions found **\n");
+ goto cleanup;
+ }