add support for GPT partition name manipulation

index 3e98821..814cb11 100644
@@ -398,6 +398,23 @@ static int gpt_verify(struct blk_desc *blk_dev_desc, const char *str_part)
 	return ret;
 }
 
+static int do_disk_guid(struct blk_desc *dev_desc, char * const namestr)
+{
+	int ret;
+	char disk_guid[UUID_STR_LEN + 1];
+
+	ret = get_disk_guid(dev_desc, disk_guid);
+	if (ret < 0)
+		return 1;
+
+	if (namestr != NULL)
+		setenv(namestr, disk_guid);
+	else
+		printf("%s\n", disk_guid);
+
+	return 0;
+}
+
 /**
  * do_gpt(): Perform GPT operations
  *

@@ -412,7 +429,7 @@ static int do_gpt(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {
 	int ret = CMD_RET_SUCCESS;
 	int dev = 0;
-	char *ep;
+	char *ep, *varname = NULL;
 	struct blk_desc *blk_dev_desc = NULL;
 
 	if (argc < 4 || argc > 5)

@@ -436,6 +453,9 @@ static int do_gpt(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 	} else if ((strcmp(argv[1], "verify") == 0)) {
 		ret = gpt_verify(blk_dev_desc, argv[4]);
 		printf("Verify GPT: ");
+	} else if (strcmp(argv[1], "guid") == 0) {
+		if (argc == 5) strcpy(varname, argv[4]);
+		return do_disk_guid(blk_dev_desc, varname);
 	} else {
 		return CMD_RET_USAGE;
 	}

@@ -458,4 +478,11 @@ U_BOOT_CMD(gpt, CONFIG_SYS_MAXARGS, 1, do_gpt,
 	" Example usage:\n"
 	" gpt write mmc 0 $partitions\n"
 	" gpt verify mmc 0 $partitions\n"
+	" guid <interface> <dev>\n"
+	"    - print disk GUID\n"
+	" guid <interface> <dev> <varname>\n"
+	"    - set environment variable to disk GUID\n"
+	" Example usage:\n"
+	" gpt guid mmc 0\n"
+	" gpt guid mmc 0 varname\n"
 );

index 1b7ba27..de35c9b 100644
@@ -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 -1;
+		} else {
+			printf("%s: ***        Using Backup GPT ***\n",
+			       __func__);
+		}
+	}
+
+	guid_bin = (unsigned char *)(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);

index 83bce05..69143bb 100644
@@ -367,6 +367,21 @@ int gpt_verify_headers(struct blk_desc *dev_desc, gpt_header *gpt_head,
 int gpt_verify_partitions(struct blk_desc *dev_desc,
 			  disk_partition_t *partitions, int parts,
 			  gpt_header *gpt_head, gpt_entry **gpt_pte);
+
+
+/**
+ * get_disk_guid() - Function to read the GUID string from a device's GPT
+ *
+ * This function reads the GUID string from a block device whose descriptor
+ * is provided.
+ *
+ * @param dev_desc - block device descriptor
+ * @param guid - pre-allocated string in which to return the GUID
+ *
+ * @return - '0' on success, otherwise error
+ */
+int get_disk_guid(struct blk_desc *dev_desc, char *guid);
+
 #endif
 
 #if CONFIG_IS_ENABLED(DOS_PARTITION)

index 814cb11..128c895 100644
@@ -19,6 +19,9 @@
 #include <linux/ctype.h>
 #include <div64.h>
 #include <memalign.h>
+#include <linux/compat.h>
+
+static LIST_HEAD(disk_partitions);
 
 /**
  * extract_env(): Expand env name from string format '&{env_name}'

@@ -151,6 +154,112 @@ static bool found_key(const char *str, const char *key)
 	return result;
 }
 
+static void del_gpt_info(void)
+{
+	struct list_head *pos = &disk_partitions;
+	struct disk_part *curr;
+	while (!list_empty(pos)) {
+		curr = list_entry(pos->next, struct disk_part, list);
+		list_del(pos->next);
+		free(curr);
+	}
+}
+
+static struct disk_part *allocate_disk_part(disk_partition_t *info, int partnum)
+{
+	struct disk_part *newpart;
+	newpart = (struct disk_part *)malloc(sizeof(*newpart));
+
+	if (!newpart)
+		return ERR_PTR(-ENOMEM);
+	newpart->gpt_part_info.start = info->start;
+	newpart->gpt_part_info.size = info->size;
+	newpart->gpt_part_info.blksz = info->blksz;
+	/*
+	 * 33 rather than 32, as each string must be null-terminated;
+	 * other extract_val() above will fail.
+	 */
+	strncpy((char *)newpart->gpt_part_info.name, (const char *)info->name, 33);
+	strncpy((char *)newpart->gpt_part_info.type, (const char *)info->type, 33);
+	newpart->gpt_part_info.bootable = info->bootable;
+#ifdef CONFIG_PARTITION_UUIDS
+	strncpy(newpart->gpt_part_info.uuid, (const char *)info->uuid,
+		UUID_STR_LEN + 1);
+#endif
+	newpart->partnum = partnum;
+
+	return newpart;
+}
+
+static void print_gpt_info(void)
+{
+	struct list_head *pos;
+	struct disk_part *curr;
+
+	list_for_each(pos, &disk_partitions) {
+		curr = list_entry(pos, struct disk_part, list);
+		printf("Partition %d:\n", curr->partnum);
+		printf("1st block %x, size %x\n", (unsigned)curr->gpt_part_info.start,
+		       (unsigned)curr->gpt_part_info.size);
+		printf("Block size %lu, name %s\n", curr->gpt_part_info.blksz,
+		       curr->gpt_part_info.name);
+		printf("Type %s, bootable %d\n", curr->gpt_part_info.type,
+		       curr->gpt_part_info.bootable);
+#ifdef CONFIG_PARTITION_UUIDS
+		printf("UUID %s\n", curr->gpt_part_info.uuid);
+#endif
+		printf("\n");
+	}
+}
+
+/*
+ * read partition info into disk_partitions list where
+ * it can be printed or modified
+ */
+static int get_gpt_info(struct blk_desc *dev_desc)
+{
+	/* start partition numbering at 1, as u-boot does */
+	int valid_parts = 1, p, ret = 0;
+	disk_partition_t info;
+	struct disk_part *new_disk_part;
+
+	if (disk_partitions.next == NULL)
+		INIT_LIST_HEAD(&disk_partitions);
+
+	for (p = 1; p <= MAX_SEARCH_PARTITIONS; p++) {
+		ret = part_get_info(dev_desc, p, &info);
+		if (ret)
+			continue;
+
+		new_disk_part = allocate_disk_part(&info, valid_parts);
+		if (IS_ERR(new_disk_part) && (valid_parts >= 2))
+			return -1;
+
+		list_add_tail(&new_disk_part->list, &disk_partitions);
+		valid_parts++;
+	}
+	if (!valid_parts) {
+		printf("** No valid partitions found **\n");
+		del_gpt_info();
+		return -1;
+	}
+	return --valid_parts;
+}
+
+/* a wrapper to test get_gpt_info */
+static int do_get_gpt_info(struct blk_desc *dev_desc)
+{
+	int ret;
+
+	ret = get_gpt_info(dev_desc);
+	if (ret > 0) {
+		print_gpt_info();
+		del_gpt_info();
+	}
+	return ret;
+}
+
+
 /**
  * set_gpt_info(): Fill partition information from string
  *		function allocates memory, remember to free!

@@ -456,6 +565,8 @@ static int do_gpt(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 	} else if (strcmp(argv[1], "guid") == 0) {
 		if (argc == 5) strcpy(varname, argv[4]);
 		return do_disk_guid(blk_dev_desc, varname);
+	} else if (strcmp(argv[1], "read") == 0) {
+		return do_get_gpt_info(blk_dev_desc);
 	} else {
 		return CMD_RET_USAGE;
 	}

@@ -478,6 +589,8 @@ U_BOOT_CMD(gpt, CONFIG_SYS_MAXARGS, 1, do_gpt,
 	" Example usage:\n"
 	" gpt write mmc 0 $partitions\n"
 	" gpt verify mmc 0 $partitions\n"
+	" read <interface> <dev>\n"
+	"    - read GPT into a data structure for manipulation\n"
 	" guid <interface> <dev>\n"
 	"    - print disk GUID\n"
 	" guid <interface> <dev> <varname>\n"

index 69143bb..87a9818 100644
@@ -9,6 +9,7 @@
 
 #include <blk.h>
 #include <ide.h>
+#include <linux/list.h>
 
 struct block_drvr {
 	char *name;

@@ -46,6 +47,8 @@ struct block_drvr {
 #define DEV_TYPE_CDROM		0x05	/* CD-ROM */
 #define DEV_TYPE_OPDISK		0x07	/* optical disk */
 
+#define MAX_SEARCH_PARTITIONS 16
+
 typedef struct disk_partition {
 	lbaint_t	start;	/* # of first block in partition	*/
 	lbaint_t	size;	/* number of blocks in partition	*/

@@ -64,6 +67,12 @@ typedef struct disk_partition {
 #endif
 } disk_partition_t;
 
+struct disk_part {
+	int partnum;
+	disk_partition_t gpt_part_info;
+	struct list_head list;
+};
+
 /* Misc _get_dev functions */
 #ifdef CONFIG_PARTITIONS
 /**

index 128c895..f2c32ae 100644
@@ -21,6 +21,9 @@
 #include <memalign.h>
 #include <linux/compat.h>
 
+/* ONEMIB is 2**20 */
+#define ONEMIB 1024*1024
+
 static LIST_HEAD(disk_partitions);
 
 /**

@@ -114,7 +117,6 @@ static char *extract_val(const char *str, const char *key)
 			break;
 		}
 	}
-
 	free(strcopy);
 
 	return new;

@@ -158,6 +160,7 @@ static void del_gpt_info(void)
 {
 	struct list_head *pos = &disk_partitions;
 	struct disk_part *curr;
+
 	while (!list_empty(pos)) {
 		curr = list_entry(pos->next, struct disk_part, list);
 		list_del(pos->next);

@@ -165,6 +168,11 @@ static void del_gpt_info(void)
 	}
 }
 
+/*
+ * The number '33' comes from the '32' in the definition of disk_partition_t
+ * in include/part.h.   That file has '37' rather than UUID_STR_LEN + 1, from
+ * include/uuid.h
+ */
 static struct disk_part *allocate_disk_part(disk_partition_t *info, int partnum)
 {
 	struct disk_part *newpart;

@@ -191,16 +199,33 @@ static struct disk_part *allocate_disk_part(disk_partition_t *info, int partnum)
 	return newpart;
 }
 
+static void prettyprint_part_size(char *sizestr, unsigned long partsize,
+				  unsigned long blksize)
+{
+	unsigned long long partbytes;
+	unsigned long partmegabytes;
+
+	partbytes = partsize * blksize;
+	partmegabytes = lldiv(partbytes, ONEMIB);
+	snprintf(sizestr, 16, "%luMiB", partmegabytes);
+}
+
 static void print_gpt_info(void)
 {
 	struct list_head *pos;
 	struct disk_part *curr;
+	char partstartstr[16];
+	char partsizestr[16];
 
 	list_for_each(pos, &disk_partitions) {
 		curr = list_entry(pos, struct disk_part, list);
+		prettyprint_part_size(partstartstr, (unsigned long)curr->gpt_part_info.start,
+				      (unsigned long) curr->gpt_part_info.blksz);
+		prettyprint_part_size(partsizestr, (unsigned long)curr->gpt_part_info.size,
+				      (unsigned long) curr->gpt_part_info.blksz);
+
 		printf("Partition %d:\n", curr->partnum);
-		printf("1st block %x, size %x\n", (unsigned)curr->gpt_part_info.start,
-		       (unsigned)curr->gpt_part_info.size);
+		printf("Start %s, size %s\n", partstartstr, partsizestr);
 		printf("Block size %lu, name %s\n", curr->gpt_part_info.blksz,
 		       curr->gpt_part_info.name);
 		printf("Type %s, bootable %d\n", curr->gpt_part_info.type,

@@ -212,6 +237,89 @@ static void print_gpt_info(void)
 	}
 }
 
+static int calc_parts_list_len(int numparts)
+{
+	/*
+	 * prefatory string:
+	 * doc/README.GPT, suggests that
+	 * int partlistlen = UUID_STR_LEN + 1 + strlen("partitions=uuid_disk=");
+	 * is correct, but extract_val() expects "uuid_disk" first.
+	 */
+	int partlistlen = UUID_STR_LEN + 1 + strlen("uuid_disk=");
+	/* for the comma */
+	partlistlen++;
+
+	/* per-partition additions; numparts starts at 1, so this should be correct */
+	partlistlen += numparts * (strlen("name=,") + 33);
+	/* 17 because partstr below is 16 chars */
+	partlistlen += numparts * (strlen("start=MiB,") + 17);
+	partlistlen += numparts * (strlen("size=MiB,") + 17);
+	partlistlen += numparts * (strlen("uuid=;") + UUID_STR_LEN + 1);
+	/* for the terminating null */
+	partlistlen ++;
+	debug("Length of partitions_list is %d for %d partitions\n", partlistlen,
+	       numparts);
+	return partlistlen;
+}
+
+/*
+ * create the string that upstream 'gpt write' command will accept as an
+ * argument
+ *
+ * From doc/README.gpt, Format of partitions layout:
+ *    "partitions=uuid_disk=...;name=u-boot,size=60MiB,uuid=...;
+ *	name=kernel,size=60MiB,uuid=...;"
+ * The fields 'name' and 'size' are mandatory for every partition.
+ * The field 'start' is optional. The fields 'uuid' and 'uuid_disk'
+ * are optional if CONFIG_RANDOM_UUID is enabled.
+ */
+static int create_gpt_partitions_list(int numparts, const char *guid, char *partitions_list)
+{
+	struct list_head *pos;
+	struct disk_part *curr;
+	char partstr[16];
+
+	if (!partitions_list)
+		return -1;
+
+	/*
+	 * README.gpt specifies starting with "partitions=" like so:
+	 *      strcpy(partitions_list, "partitions=uuid_disk=");
+	 * but that breaks extract_val, which doesn't skip over 'partitions='.
+	 */
+	strcpy(partitions_list, "uuid_disk=");
+	strncat(partitions_list, guid, UUID_STR_LEN + 1);
+	strcat(partitions_list, ";");
+
+	list_for_each(pos, &disk_partitions) {
+		curr = list_entry(pos, struct disk_part, list);
+		strcat(partitions_list, "name=");
+		/*
+		 * name is 32 chars long, per definition of disk_partition_t in part.h,
+		 * plus one extra byte for NULL
+		 */
+		strncat(partitions_list, (const char *)curr->gpt_part_info.name, 33);
+
+		strcat(partitions_list, ",start=");
+		prettyprint_part_size(partstr, (unsigned long)curr->gpt_part_info.start,
+				      (unsigned long) curr->gpt_part_info.blksz);
+		strncat(partitions_list, partstr, 17);
+
+		strcat(partitions_list, ",size=");
+		/* lbaint_t is unsigned long, per include/ide.h */
+		prettyprint_part_size(partstr, (unsigned long)curr->gpt_part_info.size,
+				      (unsigned long) curr->gpt_part_info.blksz);
+		/* one extra byte for NULL */
+		strncat(partitions_list, partstr, 17);
+
+		strcat(partitions_list, ",uuid=");
+		strncat(partitions_list, (const char *)curr->gpt_part_info.uuid,
+			UUID_STR_LEN + 1);
+		strcat(partitions_list, ";");
+	}
+	return 0;
+}
+
 /*
  * read partition info into disk_partitions list where
  * it can be printed or modified

@@ -223,8 +331,11 @@ static int get_gpt_info(struct blk_desc *dev_desc)
 	disk_partition_t info;
 	struct disk_part *new_disk_part;
 
-	if (disk_partitions.next == NULL)
-		INIT_LIST_HEAD(&disk_partitions);
+	/*
+	 * Always re-read partition info from device, in case
+	 * it has changed
+	 */
+	INIT_LIST_HEAD(&disk_partitions);
 
 	for (p = 1; p <= MAX_SEARCH_PARTITIONS; p++) {
 		ret = part_get_info(dev_desc, p, &info);

@@ -241,7 +352,6 @@ static int get_gpt_info(struct blk_desc *dev_desc)
 	if (!valid_parts) {
 		printf("** No valid partitions found **\n");
 		del_gpt_info();
-		return -1;
 	}
 	return --valid_parts;
 }

@@ -295,10 +405,13 @@ static int set_gpt_info(struct blk_desc *dev_desc,
 		return -1;
 
 	str = strdup(str_part);
+	if (str == NULL)
+		return -ENOMEM;
 
 	/* extract disk guid */
 	s = str;
 	val = extract_val(str, "uuid_disk");
+
 	if (!val) {
 #ifdef CONFIG_RANDOM_UUID
 		*str_disk_guid = malloc(UUID_STR_LEN + 1);

@@ -312,6 +425,7 @@ static int set_gpt_info(struct blk_desc *dev_desc,
 		if (extract_env(val, &p))
 			p = val;
 		*str_disk_guid = strdup(p);
+
 		free(val);
 		/* Move s to first partition */
 		strsep(&s, ";");

@@ -524,6 +638,83 @@ static int do_disk_guid(struct blk_desc *dev_desc, char * const namestr)
 	return 0;
 }
 
+static int do_flip_gpt_parts(struct blk_desc *dev_desc)
+{
+	struct list_head *pos;
+	struct disk_part *curr;
+	disk_partition_t *new_partitions = NULL;
+	char disk_guid[UUID_STR_LEN + 1];
+	char *partitions_list, *str_disk_guid;
+	u8 part_count = 0;
+	int partlistlen, ret, numparts = 0;
+
+	ret = get_disk_guid(dev_desc, disk_guid);
+	if (ret < 0)
+		return ret;
+
+	numparts = get_gpt_info(dev_desc);
+	if (numparts <  0)
+		return numparts;
+	printf("Current partition table with %d partitions is:\n", numparts);
+	print_gpt_info();
+
+	partlistlen = calc_parts_list_len(numparts);
+	partitions_list = (char *)malloc(partlistlen);
+
+	ret = create_gpt_partitions_list(numparts, (const char *) disk_guid,
+					 partitions_list);
+	if (ret < 0)
+		return ret;
+	debug("OLD partitions_list is %s with %d chars\n", partitions_list, strlen(partitions_list));
+
+	ret = set_gpt_info(dev_desc, (const char *)partitions_list, &str_disk_guid,
+			   &new_partitions, &part_count);
+	if (ret < 0)
+		return ret;
+
+	list_for_each(pos, &disk_partitions) {
+		curr = list_entry(pos, struct disk_part, list);
+		if (!strcmp((char *)curr->gpt_part_info.name, "backup_kernel"))
+			strcpy((char *)curr->gpt_part_info.name, "candidate_kernel");
+		if (!strcmp((char *)curr->gpt_part_info.name, "primary_kernel"))
+			strcpy((char *)curr->gpt_part_info.name, "backup_kernel");
+		if (!strcmp((char *)curr->gpt_part_info.name, "backup_rootfs"))
+			strcpy((char *)curr->gpt_part_info.name, "candidate_rootfs");
+		if (!strcmp((char *)curr->gpt_part_info.name, "primary_rootfs"))
+			strcpy((char *)curr->gpt_part_info.name, "backup_rootfs");
+	}
+
+	ret = create_gpt_partitions_list(numparts, (const char *) disk_guid, partitions_list);
+	if (ret < 0)
+		return ret;
+	debug("NEW partitions_list is %s with %d chars\n", partitions_list, strlen(partitions_list));
+
+	ret = set_gpt_info(dev_desc, (const char *)partitions_list, &str_disk_guid,
+			   &new_partitions, &part_count);
+	if (ret < 0)
+		return ret;
+
+	debug("Writing new partition table\n");
+	ret = gpt_restore(dev_desc, disk_guid, new_partitions, numparts);
+	if (ret < 0) {
+		printf("Writing new partition table failed\n");
+		return ret;
+	}
+
+	debug("Reading back new partition table\n");
+	numparts = get_gpt_info(dev_desc);
+	if (numparts <  0)
+		return numparts;
+	printf("new partition table with %d partitions is:\n", numparts);
+	print_gpt_info();
+
+	del_gpt_info();
+	free(partitions_list);
+	free(str_disk_guid);
+	free(new_partitions);
+	return ret;
+}
+
 /**
  * do_gpt(): Perform GPT operations
  *

@@ -567,6 +758,8 @@ static int do_gpt(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 		return do_disk_guid(blk_dev_desc, varname);
 	} else if (strcmp(argv[1], "read") == 0) {
 		return do_get_gpt_info(blk_dev_desc);
+	} else if (strcmp(argv[1], "flip") == 0) {
+		return do_flip_gpt_parts(blk_dev_desc);
 	} else {
 		return CMD_RET_USAGE;
 	}

@@ -591,6 +784,8 @@ U_BOOT_CMD(gpt, CONFIG_SYS_MAXARGS, 1, do_gpt,
 	" gpt verify mmc 0 $partitions\n"
 	" read <interface> <dev>\n"
 	"    - read GPT into a data structure for manipulation\n"
+	" flip <interface> <dev>\n"
+	"    - exchange 'primary' and 'backup' partition names in GPT"
 	" guid <interface> <dev>\n"
 	"    - print disk GUID\n"
 	" guid <interface> <dev> <varname>\n"

index 1b7ba27..20d33ef 100644
@@ -183,7 +183,7 @@ void part_print_efi(struct blk_desc *dev_desc)
 	ALLOC_CACHE_ALIGN_BUFFER_PAD(gpt_header, gpt_head, 1, dev_desc->blksz);
 	gpt_entry *gpt_pte = NULL;
 	int i = 0;
-	char uuid[37];
+	char uuid[UUID_STR_LEN + 1];
 	unsigned char *uuid_bin;
 
 	/* This function validates AND fills in the GPT header and PTE */

index 83bce05..6ace09f 100644
@@ -9,6 +9,7 @@
 
 #include <blk.h>
 #include <ide.h>
+#include <uuid.h>
 
 struct block_drvr {
 	char *name;

@@ -54,10 +55,10 @@ typedef struct disk_partition {
 	uchar	type[32];	/* string type description		*/
 	int	bootable;	/* Active/Bootable flag is set		*/
 #if CONFIG_IS_ENABLED(PARTITION_UUIDS)
-	char	uuid[37];	/* filesystem UUID as string, if exists	*/
+	char	uuid[UUID_STR_LEN + 1];	/* filesystem UUID as string, if exists	*/
 #endif
 #ifdef CONFIG_PARTITION_TYPE_GUID
-	char	type_guid[37];	/* type GUID as string, if exists	*/
+	char	type_guid[UUID_STR_LEN + 1];	/* type GUID as string, if exists	*/
 #endif
 #ifdef CONFIG_DOS_PARTITION
 	uchar	sys_ind;	/* partition type 			*/

index 6ace09f..87b1111 100644
@@ -47,12 +47,15 @@ struct block_drvr {
 #define DEV_TYPE_CDROM		0x05	/* CD-ROM */
 #define DEV_TYPE_OPDISK		0x07	/* optical disk */
 
+#define PART_NAME_LEN 32
+#define PART_TYPE_LEN 32
+
 typedef struct disk_partition {
 	lbaint_t	start;	/* # of first block in partition	*/
 	lbaint_t	size;	/* number of blocks in partition	*/
 	ulong	blksz;		/* block size in bytes			*/
-	uchar	name[32];	/* partition name			*/
-	uchar	type[32];	/* string type description		*/
+	uchar	name[PART_NAME_LEN];	/* partition name			*/
+	uchar	type[PART_TYPE_LEN];	/* string type description		*/
 	int	bootable;	/* Active/Bootable flag is set		*/
 #if CONFIG_IS_ENABLED(PARTITION_UUIDS)
 	char	uuid[UUID_STR_LEN + 1];	/* filesystem UUID as string, if exists	*/

index 3e98821..3b7d929 100644
@@ -398,6 +398,23 @@ static int gpt_verify(struct blk_desc *blk_dev_desc, const char *str_part)
 	return ret;
 }
 
+static int do_disk_guid(struct blk_desc *dev_desc, char * const namestr)
+{
+	int ret;
+	char disk_guid[UUID_STR_LEN + 1];
+
+	ret = get_disk_guid(dev_desc, disk_guid);
+	if (ret < 0)
+		return 1;
+
+	if (namestr)
+		setenv(namestr, disk_guid);
+	else
+		printf("%s\n", disk_guid);
+
+	return 0;
+}
+
 /**
  * do_gpt(): Perform GPT operations
  *

@@ -412,7 +429,7 @@ static int do_gpt(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {
 	int ret = CMD_RET_SUCCESS;
 	int dev = 0;
-	char *ep;
+	char *ep, *varname = NULL;
 	struct blk_desc *blk_dev_desc = NULL;
 
 	if (argc < 4 || argc > 5)

@@ -436,6 +453,10 @@ static int do_gpt(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 	} else if ((strcmp(argv[1], "verify") == 0)) {
 		ret = gpt_verify(blk_dev_desc, argv[4]);
 		printf("Verify GPT: ");
+	} else if (strcmp(argv[1], "guid") == 0) {
+		if (argc == 5)
+		       strcpy(varname, argv[4]);
+		return do_disk_guid(blk_dev_desc, varname);
 	} else {
 		return CMD_RET_USAGE;
 	}

@@ -458,4 +479,11 @@ U_BOOT_CMD(gpt, CONFIG_SYS_MAXARGS, 1, do_gpt,
 	" Example usage:\n"
 	" gpt write mmc 0 $partitions\n"
 	" gpt verify mmc 0 $partitions\n"
+	" guid <interface> <dev>\n"
+	"    - print disk GUID\n"
+	" guid <interface> <dev> <varname>\n"
+	"    - set environment variable to disk GUID\n"
+	" Example usage:\n"
+	" gpt guid mmc 0\n"
+	" gpt guid mmc 0 varname\n"
 );

index 20d33ef..ff9f408 100644
@@ -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 -1;
+		} else {
+			printf("%s: ***        Using Backup GPT ***\n",
+			       __func__);
+		}
+	}
+
+	guid_bin = (unsigned char *)(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);

index 87b1111..16c4a46 100644
@@ -371,6 +371,21 @@ int gpt_verify_headers(struct blk_desc *dev_desc, gpt_header *gpt_head,
 int gpt_verify_partitions(struct blk_desc *dev_desc,
 			  disk_partition_t *partitions, int parts,
 			  gpt_header *gpt_head, gpt_entry **gpt_pte);
+
+
+/**
+ * get_disk_guid() - Function to read the GUID string from a device's GPT
+ *
+ * This function reads the GUID string from a block device whose descriptor
+ * is provided.
+ *
+ * @param dev_desc - block device descriptor
+ * @param guid - pre-allocated string in which to return the GUID
+ *
+ * @return - '0' on success, otherwise error
+ */
+int get_disk_guid(struct blk_desc *dev_desc, char *guid);
+
 #endif
 
 #if CONFIG_IS_ENABLED(DOS_PARTITION)

index 3e98821..4d00a35 100644
@@ -398,6 +398,23 @@ static int gpt_verify(struct blk_desc *blk_dev_desc, const char *str_part)
 	return ret;
 }
 
+static int do_disk_guid(struct blk_desc *dev_desc, char * const namestr)
+{
+	int ret;
+	char disk_guid[UUID_STR_LEN + 1];
+
+	ret = get_disk_guid(dev_desc, disk_guid);
+	if (ret < 0)
+		return CMD_RET_FAILURE;
+
+	if (namestr)
+		setenv(namestr, disk_guid);
+	else
+		printf("%s\n", disk_guid);
+
+	return ret;
+}
+
 /**
  * do_gpt(): Perform GPT operations
  *

@@ -436,6 +453,8 @@ static int do_gpt(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 	} else if ((strcmp(argv[1], "verify") == 0)) {
 		ret = gpt_verify(blk_dev_desc, argv[4]);
 		printf("Verify GPT: ");
+	} else if (strcmp(argv[1], "guid") == 0) {
+		return do_disk_guid(blk_dev_desc, argv[4]);
 	} else {
 		return CMD_RET_USAGE;
 	}

@@ -458,4 +477,11 @@ U_BOOT_CMD(gpt, CONFIG_SYS_MAXARGS, 1, do_gpt,
 	" Example usage:\n"
 	" gpt write mmc 0 $partitions\n"
 	" gpt verify mmc 0 $partitions\n"
+	" guid <interface> <dev>\n"
+	"    - print disk GUID\n"
+	" guid <interface> <dev> <varname>\n"
+	"    - set environment variable to disk GUID\n"
+	" Example usage:\n"
+	" gpt guid mmc 0\n"
+	" gpt guid mmc 0 varname\n"
 );

index 20d33ef..71c3cb3 100644
@@ -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);

index 87b1111..16c4a46 100644
@@ -371,6 +371,21 @@ int gpt_verify_headers(struct blk_desc *dev_desc, gpt_header *gpt_head,
 int gpt_verify_partitions(struct blk_desc *dev_desc,
 			  disk_partition_t *partitions, int parts,
 			  gpt_header *gpt_head, gpt_entry **gpt_pte);
+
+
+/**
+ * get_disk_guid() - Function to read the GUID string from a device's GPT
+ *
+ * This function reads the GUID string from a block device whose descriptor
+ * is provided.
+ *
+ * @param dev_desc - block device descriptor
+ * @param guid - pre-allocated string in which to return the GUID
+ *
+ * @return - '0' on success, otherwise error
+ */
+int get_disk_guid(struct blk_desc *dev_desc, char *guid);
+
 #endif
 
 #if CONFIG_IS_ENABLED(DOS_PARTITION)

index 3e98821..65fb80b 100644
@@ -398,6 +398,23 @@ static int gpt_verify(struct blk_desc *blk_dev_desc, const char *str_part)
 	return ret;
 }
 
+static int do_disk_guid(struct blk_desc *dev_desc, char * const namestr)
+{
+	int ret;
+	char disk_guid[UUID_STR_LEN + 1];
+
+	ret = get_disk_guid(dev_desc, disk_guid);
+	if (ret < 0)
+		return CMD_RET_FAILURE;
+
+	if (namestr)
+		setenv(namestr, disk_guid);
+	else
+		printf("%s\n", disk_guid);
+
+	return ret;
+}
+
 /**
  * do_gpt(): Perform GPT operations
  *

@@ -436,6 +453,8 @@ static int do_gpt(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 	} else if ((strcmp(argv[1], "verify") == 0)) {
 		ret = gpt_verify(blk_dev_desc, argv[4]);
 		printf("Verify GPT: ");
+	} else if (strcmp(argv[1], "guid") == 0) {
+		ret = do_disk_guid(blk_dev_desc, argv[4]);
 	} else {
 		return CMD_RET_USAGE;
 	}

@@ -458,4 +477,11 @@ U_BOOT_CMD(gpt, CONFIG_SYS_MAXARGS, 1, do_gpt,
 	" Example usage:\n"
 	" gpt write mmc 0 $partitions\n"
 	" gpt verify mmc 0 $partitions\n"
+	" guid <interface> <dev>\n"
+	"    - print disk GUID\n"
+	" guid <interface> <dev> <varname>\n"
+	"    - set environment variable to disk GUID\n"
+	" Example usage:\n"
+	" gpt guid mmc 0\n"
+	" gpt guid mmc 0 varname\n"
 );

index 20d33ef..71c3cb3 100644
@@ -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);

index 87b1111..16c4a46 100644
@@ -371,6 +371,21 @@ int gpt_verify_headers(struct blk_desc *dev_desc, gpt_header *gpt_head,
 int gpt_verify_partitions(struct blk_desc *dev_desc,
 			  disk_partition_t *partitions, int parts,
 			  gpt_header *gpt_head, gpt_entry **gpt_pte);
+
+
+/**
+ * get_disk_guid() - Function to read the GUID string from a device's GPT
+ *
+ * This function reads the GUID string from a block device whose descriptor
+ * is provided.
+ *
+ * @param dev_desc - block device descriptor
+ * @param guid - pre-allocated string in which to return the GUID
+ *
+ * @return - '0' on success, otherwise error
+ */
+int get_disk_guid(struct blk_desc *dev_desc, char *guid);
+
 #endif
 
 #if CONFIG_IS_ENABLED(DOS_PARTITION)

index 491b02d..e640a55 100644
@@ -388,7 +388,6 @@ cleanup:
 
 #define PART_UNSPECIFIED -2
 #define PART_AUTO -1
-#define MAX_SEARCH_PARTITIONS 16
 int blk_get_device_part_str(const char *ifname, const char *dev_part_str,
 			     struct blk_desc **dev_desc,
 			     disk_partition_t *info, int allow_whole_dev)

index 16c4a46..c41aa6a 100644
@@ -49,6 +49,7 @@ struct block_drvr {
 
 #define PART_NAME_LEN 32
 #define PART_TYPE_LEN 32
+#define MAX_SEARCH_PARTITIONS 64
 
 typedef struct disk_partition {
 	lbaint_t	start;	/* # of first block in partition	*/

index 4d00a35..5c2651f 100644
@@ -19,6 +19,9 @@
 #include <linux/ctype.h>
 #include <div64.h>
 #include <memalign.h>
+#include <linux/compat.h>
+
+static LIST_HEAD(disk_partitions);
 
 /**
  * extract_env(): Expand env name from string format '&{env_name}'

@@ -151,6 +154,111 @@ static bool found_key(const char *str, const char *key)
 	return result;
 }
 
+static void del_gpt_info(void)
+{
+	struct list_head *pos = &disk_partitions;
+	struct disk_part *curr;
+	while (!list_empty(pos)) {
+		curr = list_entry(pos->next, struct disk_part, list);
+		list_del(pos->next);
+		free(curr);
+	}
+}
+
+static struct disk_part *allocate_disk_part(disk_partition_t *info, int partnum)
+{
+	struct disk_part *newpart;
+	newpart = (struct disk_part *)malloc(sizeof(*newpart));
+	if (!newpart)
+		return ERR_PTR(-ENOMEM);
+	memset(newpart, '\0', sizeof(newpart));
+
+	newpart->gpt_part_info.start = info->start;
+	newpart->gpt_part_info.size = info->size;
+	newpart->gpt_part_info.blksz = info->blksz;
+	strncpy((char *)newpart->gpt_part_info.name, (const char *)info->name, PART_NAME_LEN);
+	newpart->gpt_part_info.name[PART_NAME_LEN - 1] = '\0';
+	strncpy((char *)newpart->gpt_part_info.type, (const char *)info->type, PART_TYPE_LEN);
+	newpart->gpt_part_info.type[PART_TYPE_LEN - 1] = '\0';
+	newpart->gpt_part_info.bootable = info->bootable;
+#ifdef CONFIG_PARTITION_UUIDS
+	strncpy(newpart->gpt_part_info.uuid, (const char *)info->uuid,
+		UUID_STR_LEN);
+#endif
+	newpart->partnum = partnum;
+
+	return newpart;
+}
+
+static void print_gpt_info(void)
+{
+	struct list_head *pos;
+	struct disk_part *curr;
+
+	list_for_each(pos, &disk_partitions) {
+		curr = list_entry(pos, struct disk_part, list);
+		printf("Partition %d:\n", curr->partnum);
+		printf("1st block %x, size %x\n", (unsigned)curr->gpt_part_info.start,
+		       (unsigned)curr->gpt_part_info.size);
+		printf("Block size %lu, name %s\n", curr->gpt_part_info.blksz,
+		       curr->gpt_part_info.name);
+		printf("Type %s, bootable %d\n", curr->gpt_part_info.type,
+		       curr->gpt_part_info.bootable);
+#ifdef CONFIG_PARTITION_UUIDS
+		printf("UUID %s\n", curr->gpt_part_info.uuid);
+#endif
+		printf("\n");
+	}
+}
+
+/*
+ * read partition info into disk_partitions list where
+ * it can be printed or modified
+ */
+static int get_gpt_info(struct blk_desc *dev_desc)
+{
+	/* start partition numbering at 1, as U-Boot does */
+	int valid_parts = 1, p, ret;
+	disk_partition_t info;
+	struct disk_part *new_disk_part;
+
+	if (disk_partitions.next == NULL)
+		INIT_LIST_HEAD(&disk_partitions);
+
+	for (p = 1; p <= MAX_SEARCH_PARTITIONS; p++) {
+		ret = part_get_info(dev_desc, p, &info);
+		if (ret)
+			continue;
+
+		new_disk_part = allocate_disk_part(&info, valid_parts);
+		if (IS_ERR(new_disk_part) && valid_parts >= 2)
+			return -ENODEV;
+
+		list_add_tail(&new_disk_part->list, &disk_partitions);
+		valid_parts++;
+	}
+	if (!valid_parts) {
+		printf("** No valid partitions found **\n");
+		del_gpt_info();
+		return -ENODEV;
+	}
+	return --valid_parts;
+}
+
+/* a wrapper to test get_gpt_info */
+static int do_get_gpt_info(struct blk_desc *dev_desc)
+{
+	int ret;
+
+	ret = get_gpt_info(dev_desc);
+	if (ret > 0) {
+		print_gpt_info();
+		del_gpt_info();
+	}
+	return ret;
+}
+
+
 /**
  * set_gpt_info(): Fill partition information from string
  *		function allocates memory, remember to free!

@@ -455,6 +563,8 @@ static int do_gpt(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 		printf("Verify GPT: ");
 	} else if (strcmp(argv[1], "guid") == 0) {
 		return do_disk_guid(blk_dev_desc, argv[4]);
+	} else if (strcmp(argv[1], "read") == 0) {
+		return do_get_gpt_info(blk_dev_desc);
 	} else {
 		return CMD_RET_USAGE;
 	}

@@ -477,6 +587,8 @@ U_BOOT_CMD(gpt, CONFIG_SYS_MAXARGS, 1, do_gpt,
 	" Example usage:\n"
 	" gpt write mmc 0 $partitions\n"
 	" gpt verify mmc 0 $partitions\n"
+	" read <interface> <dev>\n"
+	"    - read GPT into a data structure for manipulation\n"
 	" guid <interface> <dev>\n"
 	"    - print disk GUID\n"
 	" guid <interface> <dev> <varname>\n"

index c41aa6a..0cd803a 100644
@@ -10,6 +10,7 @@
 #include <blk.h>
 #include <ide.h>
 #include <uuid.h>
+#include <linux/list.h>
 
 struct block_drvr {
 	char *name;

@@ -69,6 +70,12 @@ typedef struct disk_partition {
 #endif
 } disk_partition_t;
 
+struct disk_part {
+	int partnum;
+	disk_partition_t gpt_part_info;
+	struct list_head list;
+};
+
 /* Misc _get_dev functions */
 #ifdef CONFIG_PARTITIONS
 /**

index 65fb80b..669031f8 100644
@@ -19,6 +19,9 @@
 #include <linux/ctype.h>
 #include <div64.h>
 #include <memalign.h>
+#include <linux/compat.h>
+
+static LIST_HEAD(disk_partitions);
 
 /**
  * extract_env(): Expand env name from string format '&{env_name}'

@@ -151,6 +154,119 @@ static bool found_key(const char *str, const char *key)
 	return result;
 }
 
+static void del_gpt_info(void)
+{
+	struct list_head *pos = &disk_partitions;
+	struct disk_part *curr;
+	while (!list_empty(pos)) {
+		curr = list_entry(pos->next, struct disk_part, list);
+		list_del(pos->next);
+		free(curr);
+	}
+}
+
+static struct disk_part *allocate_disk_part(disk_partition_t *info, int partnum)
+{
+	struct disk_part *newpart;
+	newpart = (struct disk_part *)malloc(sizeof(*newpart));
+	if (!newpart)
+		return ERR_PTR(-ENOMEM);
+	memset(newpart, '\0', sizeof(newpart));
+
+	newpart->gpt_part_info.start = info->start;
+	newpart->gpt_part_info.size = info->size;
+	newpart->gpt_part_info.blksz = info->blksz;
+	strncpy((char *)newpart->gpt_part_info.name, (const char *)info->name,
+		PART_NAME_LEN);
+	newpart->gpt_part_info.name[PART_NAME_LEN - 1] = '\0';
+	strncpy((char *)newpart->gpt_part_info.type, (const char *)info->type,
+		PART_TYPE_LEN);
+	newpart->gpt_part_info.type[PART_TYPE_LEN - 1] = '\0';
+	newpart->gpt_part_info.bootable = info->bootable;
+#ifdef CONFIG_PARTITION_UUIDS
+	strncpy(newpart->gpt_part_info.uuid, (const char *)info->uuid,
+		UUID_STR_LEN);
+	/* UUID_STR_LEN is correct, as uuid[]'s length is UUID_STR_LEN+1 chars */
+	newpart->gpt_part_info.uuid[UUID_STR_LEN] = '\0';
+#endif
+	newpart->partnum = partnum;
+
+	return newpart;
+}
+
+static void print_gpt_info(void)
+{
+	struct list_head *pos;
+	struct disk_part *curr;
+
+	list_for_each(pos, &disk_partitions) {
+		curr = list_entry(pos, struct disk_part, list);
+		printf("Partition %d:\n", curr->partnum);
+		printf("1st block %x, size %x\n", (unsigned)curr->gpt_part_info.start,
+		       (unsigned)curr->gpt_part_info.size);
+		printf("Block size %lu, name %s\n", curr->gpt_part_info.blksz,
+		       curr->gpt_part_info.name);
+		printf("Type %s, bootable %d\n", curr->gpt_part_info.type,
+		       curr->gpt_part_info.bootable);
+#ifdef CONFIG_PARTITION_UUIDS
+		printf("UUID %s\n", curr->gpt_part_info.uuid);
+#endif
+		printf("\n");
+	}
+}
+
+/*
+ * read partition info into disk_partitions list where
+ * it can be printed or modified
+ */
+static int get_gpt_info(struct blk_desc *dev_desc)
+{
+	/* start partition numbering at 1, as U-Boot does */
+	int valid_parts = 1, p, ret;
+	disk_partition_t info;
+	struct disk_part *new_disk_part;
+
+	if (disk_partitions.next == NULL)
+		INIT_LIST_HEAD(&disk_partitions);
+
+	for (p = 1; p <= MAX_SEARCH_PARTITIONS; p++) {
+		ret = part_get_info(dev_desc, p, &info);
+		if (ret)
+			continue;
+
+		new_disk_part = allocate_disk_part(&info, valid_parts);
+		if (IS_ERR(new_disk_part))
+			goto out;
+
+		list_add_tail(&new_disk_part->list, &disk_partitions);
+		valid_parts++;
+	}
+	if (!valid_parts) {
+		printf("** No valid partitions found **\n");
+		goto out;
+	}
+	return --valid_parts;
+ out:
+	if (valid_parts >= 2)
+		del_gpt_info();
+	return -ENODEV;
+}
+
+/* a wrapper to test get_gpt_info */
+static int do_get_gpt_info(struct blk_desc *dev_desc)
+{
+	int ret;
+
+	ret = get_gpt_info(dev_desc);
+	if (ret > 0) {
+		print_gpt_info();
+		del_gpt_info();
+		return 0;
+	}
+	return ret;
+}
+
+
 /**
  * set_gpt_info(): Fill partition information from string
  *		function allocates memory, remember to free!

@@ -455,6 +571,8 @@ static int do_gpt(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 		printf("Verify GPT: ");
 	} else if (strcmp(argv[1], "guid") == 0) {
 		ret = do_disk_guid(blk_dev_desc, argv[4]);
+	} else if (strcmp(argv[1], "read") == 0) {
+		ret = do_get_gpt_info(blk_dev_desc);
 	} else {
 		return CMD_RET_USAGE;
 	}

@@ -477,6 +595,8 @@ U_BOOT_CMD(gpt, CONFIG_SYS_MAXARGS, 1, do_gpt,
 	" Example usage:\n"
 	" gpt write mmc 0 $partitions\n"
 	" gpt verify mmc 0 $partitions\n"
+	" read <interface> <dev>\n"
+	"    - read GPT into a data structure for manipulation\n"
 	" guid <interface> <dev>\n"
 	"    - print disk GUID\n"
 	" guid <interface> <dev> <varname>\n"

index c41aa6a..0cd803a 100644
@@ -10,6 +10,7 @@
 #include <blk.h>
 #include <ide.h>
 #include <uuid.h>
+#include <linux/list.h>
 
 struct block_drvr {
 	char *name;

@@ -69,6 +70,12 @@ typedef struct disk_partition {
 #endif
 } disk_partition_t;
 
+struct disk_part {
+	int partnum;
+	disk_partition_t gpt_part_info;
+	struct list_head list;
+};
+
 /* Misc _get_dev functions */
 #ifdef CONFIG_PARTITIONS
 /**

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