1 files changed, 669 insertions, 0 deletions

diff --git a/qemu/roms/u-boot/disk/part_efi.c b/qemu/roms/u-boot/disk/part_efi.c
new file mode 100644
index 000000000..c74b7b917
--- /dev/null
+++ b/qemu/roms/u-boot/disk/part_efi.c
@@ -0,0 +1,669 @@
+/*
+ * Copyright (C) 2008 RuggedCom, Inc.
+ * Richard Retanubun <RichardRetanubun@RuggedCom.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+/*
+ * Problems with CONFIG_SYS_64BIT_LBA:
+ *
+ * struct disk_partition.start in include/part.h is sized as ulong.
+ * When CONFIG_SYS_64BIT_LBA is activated, lbaint_t changes from ulong to uint64_t.
+ * For now, it is cast back to ulong at assignment.
+ *
+ * This limits the maximum size of addressable storage to < 2 Terra Bytes
+ */
+#include <asm/unaligned.h>
+#include <common.h>
+#include <command.h>
+#include <ide.h>
+#include <malloc.h>
+#include <part_efi.h>
+#include <linux/ctype.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#ifdef HAVE_BLOCK_DEVICE
+/**
+ * efi_crc32() - EFI version of crc32 function
+ * @buf: buffer to calculate crc32 of
+ * @len - length of buf
+ *
+ * Description: Returns EFI-style CRC32 value for @buf
+ */
+static inline u32 efi_crc32(const void *buf, u32 len)
+{
+	return crc32(0, buf, len);
+}
+
+/*
+ * Private function prototypes
+ */
+
+static int pmbr_part_valid(struct partition *part);
+static int is_pmbr_valid(legacy_mbr * mbr);
+static int is_gpt_valid(block_dev_desc_t * dev_desc, unsigned long long lba,
+				gpt_header * pgpt_head, gpt_entry ** pgpt_pte);
+static gpt_entry *alloc_read_gpt_entries(block_dev_desc_t * dev_desc,
+				gpt_header * pgpt_head);
+static int is_pte_valid(gpt_entry * pte);
+
+static char *print_efiname(gpt_entry *pte)
+{
+	static char name[PARTNAME_SZ + 1];
+	int i;
+	for (i = 0; i < PARTNAME_SZ; i++) {
+		u8 c;
+		c = pte->partition_name[i] & 0xff;
+		c = (c && !isprint(c)) ? '.' : c;
+		name[i] = c;
+	}
+	name[PARTNAME_SZ] = 0;
+	return name;
+}
+
+static efi_guid_t system_guid = PARTITION_SYSTEM_GUID;
+
+static inline int is_bootable(gpt_entry *p)
+{
+	return p->attributes.fields.legacy_bios_bootable ||
+		!memcmp(&(p->partition_type_guid), &system_guid,
+			sizeof(efi_guid_t));
+}
+
+#ifdef CONFIG_EFI_PARTITION
+/*
+ * Public Functions (include/part.h)
+ */
+
+void print_part_efi(block_dev_desc_t * 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];
+	unsigned char *uuid_bin;
+
+	if (!dev_desc) {
+		printf("%s: Invalid Argument(s)\n", __func__);
+		return;
+	}
+	/* 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;
+		} else {
+			printf("%s: ***        Using Backup GPT ***\n",
+			       __func__);
+		}
+	}
+
+	debug("%s: gpt-entry at %p\n", __func__, gpt_pte);
+
+	printf("Part\tStart LBA\tEnd LBA\t\tName\n");
+	printf("\tAttributes\n");
+	printf("\tType GUID\n");
+	printf("\tPartition GUID\n");
+
+	for (i = 0; i < le32_to_cpu(gpt_head->num_partition_entries); i++) {
+		/* Stop at the first non valid PTE */
+		if (!is_pte_valid(&gpt_pte[i]))
+			break;
+
+		printf("%3d\t0x%08llx\t0x%08llx\t\"%s\"\n", (i + 1),
+			le64_to_cpu(gpt_pte[i].starting_lba),
+			le64_to_cpu(gpt_pte[i].ending_lba),
+			print_efiname(&gpt_pte[i]));
+		printf("\tattrs:\t0x%016llx\n", gpt_pte[i].attributes.raw);
+		uuid_bin = (unsigned char *)gpt_pte[i].partition_type_guid.b;
+		uuid_bin_to_str(uuid_bin, uuid, UUID_STR_FORMAT_GUID);
+		printf("\ttype:\t%s\n", uuid);
+		uuid_bin = (unsigned char *)gpt_pte[i].unique_partition_guid.b;
+		uuid_bin_to_str(uuid_bin, uuid, UUID_STR_FORMAT_GUID);
+		printf("\tguid:\t%s\n", uuid);
+	}
+
+	/* Remember to free pte */
+	free(gpt_pte);
+	return;
+}
+
+int get_partition_info_efi(block_dev_desc_t * dev_desc, int part,
+				disk_partition_t * info)
+{
+	ALLOC_CACHE_ALIGN_BUFFER_PAD(gpt_header, gpt_head, 1, dev_desc->blksz);
+	gpt_entry *gpt_pte = NULL;
+
+	/* "part" argument must be at least 1 */
+	if (!dev_desc || !info || part < 1) {
+		printf("%s: Invalid Argument(s)\n", __func__);
+		return -1;
+	}
+
+	/* 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__);
+		}
+	}
+
+	if (part > le32_to_cpu(gpt_head->num_partition_entries) ||
+	    !is_pte_valid(&gpt_pte[part - 1])) {
+		debug("%s: *** ERROR: Invalid partition number %d ***\n",
+			__func__, part);
+		free(gpt_pte);
+		return -1;
+	}
+
+	/* The ulong casting limits the maximum disk size to 2 TB */
+	info->start = (u64)le64_to_cpu(gpt_pte[part - 1].starting_lba);
+	/* The ending LBA is inclusive, to calculate size, add 1 to it */
+	info->size = ((u64)le64_to_cpu(gpt_pte[part - 1].ending_lba) + 1)
+		     - info->start;
+	info->blksz = dev_desc->blksz;
+
+	sprintf((char *)info->name, "%s",
+			print_efiname(&gpt_pte[part - 1]));
+	sprintf((char *)info->type, "U-Boot");
+	info->bootable = is_bootable(&gpt_pte[part - 1]);
+#ifdef CONFIG_PARTITION_UUIDS
+	uuid_bin_to_str(gpt_pte[part - 1].unique_partition_guid.b, info->uuid,
+			UUID_STR_FORMAT_GUID);
+#endif
+
+	debug("%s: start 0x" LBAF ", size 0x" LBAF ", name %s", __func__,
+	      info->start, info->size, info->name);
+
+	/* Remember to free pte */
+	free(gpt_pte);
+	return 0;
+}
+
+int test_part_efi(block_dev_desc_t * dev_desc)
+{
+	ALLOC_CACHE_ALIGN_BUFFER_PAD(legacy_mbr, legacymbr, 1, dev_desc->blksz);
+
+	/* Read legacy MBR from block 0 and validate it */
+	if ((dev_desc->block_read(dev_desc->dev, 0, 1, (ulong *)legacymbr) != 1)
+		|| (is_pmbr_valid(legacymbr) != 1)) {
+		return -1;
+	}
+	return 0;
+}
+
+/**
+ * set_protective_mbr(): Set the EFI protective MBR
+ * @param dev_desc - block device descriptor
+ *
+ * @return - zero on success, otherwise error
+ */
+static int set_protective_mbr(block_dev_desc_t *dev_desc)
+{
+	/* Setup the Protective MBR */
+	ALLOC_CACHE_ALIGN_BUFFER(legacy_mbr, p_mbr, 1);
+	memset(p_mbr, 0, sizeof(*p_mbr));
+
+	if (p_mbr == NULL) {
+		printf("%s: calloc failed!\n", __func__);
+		return -1;
+	}
+	/* Append signature */
+	p_mbr->signature = MSDOS_MBR_SIGNATURE;
+	p_mbr->partition_record[0].sys_ind = EFI_PMBR_OSTYPE_EFI_GPT;
+	p_mbr->partition_record[0].start_sect = 1;
+	p_mbr->partition_record[0].nr_sects = (u32) dev_desc->lba;
+
+	/* Write MBR sector to the MMC device */
+	if (dev_desc->block_write(dev_desc->dev, 0, 1, p_mbr) != 1) {
+		printf("** Can't write to device %d **\n",
+			dev_desc->dev);
+		return -1;
+	}
+
+	return 0;
+}
+
+int write_gpt_table(block_dev_desc_t *dev_desc,
+		gpt_header *gpt_h, gpt_entry *gpt_e)
+{
+	const int pte_blk_cnt = BLOCK_CNT((gpt_h->num_partition_entries
+					   * sizeof(gpt_entry)), dev_desc);
+	u32 calc_crc32;
+	u64 val;
+
+	debug("max lba: %x\n", (u32) dev_desc->lba);
+	/* Setup the Protective MBR */
+	if (set_protective_mbr(dev_desc) < 0)
+		goto err;
+
+	/* Generate CRC for the Primary GPT Header */
+	calc_crc32 = efi_crc32((const unsigned char *)gpt_e,
+			      le32_to_cpu(gpt_h->num_partition_entries) *
+			      le32_to_cpu(gpt_h->sizeof_partition_entry));
+	gpt_h->partition_entry_array_crc32 = cpu_to_le32(calc_crc32);
+
+	calc_crc32 = efi_crc32((const unsigned char *)gpt_h,
+			      le32_to_cpu(gpt_h->header_size));
+	gpt_h->header_crc32 = cpu_to_le32(calc_crc32);
+
+	/* Write the First GPT to the block right after the Legacy MBR */
+	if (dev_desc->block_write(dev_desc->dev, 1, 1, gpt_h) != 1)
+		goto err;
+
+	if (dev_desc->block_write(dev_desc->dev, 2, pte_blk_cnt, gpt_e)
+	    != pte_blk_cnt)
+		goto err;
+
+	/* recalculate the values for the Backup GPT Header */
+	val = le64_to_cpu(gpt_h->my_lba);
+	gpt_h->my_lba = gpt_h->alternate_lba;
+	gpt_h->alternate_lba = cpu_to_le64(val);
+	gpt_h->header_crc32 = 0;
+
+	calc_crc32 = efi_crc32((const unsigned char *)gpt_h,
+			      le32_to_cpu(gpt_h->header_size));
+	gpt_h->header_crc32 = cpu_to_le32(calc_crc32);
+
+	if (dev_desc->block_write(dev_desc->dev,
+				  le32_to_cpu(gpt_h->last_usable_lba + 1),
+				  pte_blk_cnt, gpt_e) != pte_blk_cnt)
+		goto err;
+
+	if (dev_desc->block_write(dev_desc->dev,
+				  le32_to_cpu(gpt_h->my_lba), 1, gpt_h) != 1)
+		goto err;
+
+	debug("GPT successfully written to block device!\n");
+	return 0;
+
+ err:
+	printf("** Can't write to device %d **\n", dev_desc->dev);
+	return -1;
+}
+
+int gpt_fill_pte(gpt_header *gpt_h, gpt_entry *gpt_e,
+		disk_partition_t *partitions, int parts)
+{
+	u32 offset = (u32)le32_to_cpu(gpt_h->first_usable_lba);
+	ulong start;
+	int i, k;
+	size_t efiname_len, dosname_len;
+#ifdef CONFIG_PARTITION_UUIDS
+	char *str_uuid;
+	unsigned char *bin_uuid;
+#endif
+
+	for (i = 0; i < parts; i++) {
+		/* partition starting lba */
+		start = partitions[i].start;
+		if (start && (start < offset)) {
+			printf("Partition overlap\n");
+			return -1;
+		}
+		if (start) {
+			gpt_e[i].starting_lba = cpu_to_le64(start);
+			offset = start + partitions[i].size;
+		} else {
+			gpt_e[i].starting_lba = cpu_to_le64(offset);
+			offset += partitions[i].size;
+		}
+		if (offset >= gpt_h->last_usable_lba) {
+			printf("Partitions layout exceds disk size\n");
+			return -1;
+		}
+		/* partition ending lba */
+		if ((i == parts - 1) && (partitions[i].size == 0))
+			/* extend the last partition to maximuim */
+			gpt_e[i].ending_lba = gpt_h->last_usable_lba;
+		else
+			gpt_e[i].ending_lba = cpu_to_le64(offset - 1);
+
+		/* partition type GUID */
+		memcpy(gpt_e[i].partition_type_guid.b,
+			&PARTITION_BASIC_DATA_GUID, 16);
+
+#ifdef CONFIG_PARTITION_UUIDS
+		str_uuid = partitions[i].uuid;
+		bin_uuid = gpt_e[i].unique_partition_guid.b;
+
+		if (uuid_str_to_bin(str_uuid, bin_uuid, UUID_STR_FORMAT_STD)) {
+			printf("Partition no. %d: invalid guid: %s\n",
+				i, str_uuid);
+			return -1;
+		}
+#endif
+
+		/* partition attributes */
+		memset(&gpt_e[i].attributes, 0,
+		       sizeof(gpt_entry_attributes));
+
+		/* partition name */
+		efiname_len = sizeof(gpt_e[i].partition_name)
+			/ sizeof(efi_char16_t);
+		dosname_len = sizeof(partitions[i].name);
+
+		memset(gpt_e[i].partition_name, 0,
+		       sizeof(gpt_e[i].partition_name));
+
+		for (k = 0; k < min(dosname_len, efiname_len); k++)
+			gpt_e[i].partition_name[k] =
+				(efi_char16_t)(partitions[i].name[k]);
+
+		debug("%s: name: %s offset[%d]: 0x%x size[%d]: 0x" LBAF "\n",
+		      __func__, partitions[i].name, i,
+		      offset, i, partitions[i].size);
+	}
+
+	return 0;
+}
+
+int gpt_fill_header(block_dev_desc_t *dev_desc, gpt_header *gpt_h,
+		char *str_guid, int parts_count)
+{
+	gpt_h->signature = cpu_to_le64(GPT_HEADER_SIGNATURE);
+	gpt_h->revision = cpu_to_le32(GPT_HEADER_REVISION_V1);
+	gpt_h->header_size = cpu_to_le32(sizeof(gpt_header));
+	gpt_h->my_lba = cpu_to_le64(1);
+	gpt_h->alternate_lba = cpu_to_le64(dev_desc->lba - 1);
+	gpt_h->first_usable_lba = cpu_to_le64(34);
+	gpt_h->last_usable_lba = cpu_to_le64(dev_desc->lba - 34);
+	gpt_h->partition_entry_lba = cpu_to_le64(2);
+	gpt_h->num_partition_entries = cpu_to_le32(GPT_ENTRY_NUMBERS);
+	gpt_h->sizeof_partition_entry = cpu_to_le32(sizeof(gpt_entry));
+	gpt_h->header_crc32 = 0;
+	gpt_h->partition_entry_array_crc32 = 0;
+
+	if (uuid_str_to_bin(str_guid, gpt_h->disk_guid.b, UUID_STR_FORMAT_GUID))
+		return -1;
+
+	return 0;
+}
+
+int gpt_restore(block_dev_desc_t *dev_desc, char *str_disk_guid,
+		disk_partition_t *partitions, int parts_count)
+{
+	int ret;
+
+	gpt_header *gpt_h = calloc(1, PAD_TO_BLOCKSIZE(sizeof(gpt_header),
+						       dev_desc));
+	gpt_entry *gpt_e;
+
+	if (gpt_h == NULL) {
+		printf("%s: calloc failed!\n", __func__);
+		return -1;
+	}
+
+	gpt_e = calloc(1, PAD_TO_BLOCKSIZE(GPT_ENTRY_NUMBERS
+					       * sizeof(gpt_entry),
+					       dev_desc));
+	if (gpt_e == NULL) {
+		printf("%s: calloc failed!\n", __func__);
+		free(gpt_h);
+		return -1;
+	}
+
+	/* Generate Primary GPT header (LBA1) */
+	ret = gpt_fill_header(dev_desc, gpt_h, str_disk_guid, parts_count);
+	if (ret)
+		goto err;
+
+	/* Generate partition entries */
+	ret = gpt_fill_pte(gpt_h, gpt_e, partitions, parts_count);
+	if (ret)
+		goto err;
+
+	/* Write GPT partition table */
+	ret = write_gpt_table(dev_desc, gpt_h, gpt_e);
+
+err:
+	free(gpt_e);
+	free(gpt_h);
+	return ret;
+}
+#endif
+
+/*
+ * Private functions
+ */
+/*
+ * pmbr_part_valid(): Check for EFI partition signature
+ *
+ * Returns: 1 if EFI GPT partition type is found.
+ */
+static int pmbr_part_valid(struct partition *part)
+{
+	if (part->sys_ind == EFI_PMBR_OSTYPE_EFI_GPT &&
+		get_unaligned_le32(&part->start_sect) == 1UL) {
+		return 1;
+	}
+
+	return 0;
+}
+
+/*
+ * is_pmbr_valid(): test Protective MBR for validity
+ *
+ * Returns: 1 if PMBR is valid, 0 otherwise.
+ * Validity depends on two things:
+ *  1) MSDOS signature is in the last two bytes of the MBR
+ *  2) One partition of type 0xEE is found, checked by pmbr_part_valid()
+ */
+static int is_pmbr_valid(legacy_mbr * mbr)
+{
+	int i = 0;
+
+	if (!mbr || le16_to_cpu(mbr->signature) != MSDOS_MBR_SIGNATURE)
+		return 0;
+
+	for (i = 0; i < 4; i++) {
+		if (pmbr_part_valid(&mbr->partition_record[i])) {
+			return 1;
+		}
+	}
+	return 0;
+}
+
+/**
+ * is_gpt_valid() - tests one GPT header and PTEs for validity
+ *
+ * lba is the logical block address of the GPT header to test
+ * gpt is a GPT header ptr, filled on return.
+ * ptes is a PTEs ptr, filled on return.
+ *
+ * Description: returns 1 if valid,  0 on error.
+ * If valid, returns pointers to PTEs.
+ */
+static int is_gpt_valid(block_dev_desc_t * dev_desc, unsigned long long lba,
+			gpt_header * pgpt_head, gpt_entry ** pgpt_pte)
+{
+	u32 crc32_backup = 0;
+	u32 calc_crc32;
+	unsigned long long lastlba;
+
+	if (!dev_desc || !pgpt_head) {
+		printf("%s: Invalid Argument(s)\n", __func__);
+		return 0;
+	}
+
+	/* Read GPT Header from device */
+	if (dev_desc->block_read(dev_desc->dev, lba, 1, pgpt_head) != 1) {
+		printf("*** ERROR: Can't read GPT header ***\n");
+		return 0;
+	}
+
+	/* Check the GPT header signature */
+	if (le64_to_cpu(pgpt_head->signature) != GPT_HEADER_SIGNATURE) {
+		printf("GUID Partition Table Header signature is wrong:"
+			"0x%llX != 0x%llX\n",
+			le64_to_cpu(pgpt_head->signature),
+			GPT_HEADER_SIGNATURE);
+		return 0;
+	}
+
+	/* Check the GUID Partition Table CRC */
+	memcpy(&crc32_backup, &pgpt_head->header_crc32, sizeof(crc32_backup));
+	memset(&pgpt_head->header_crc32, 0, sizeof(pgpt_head->header_crc32));
+
+	calc_crc32 = efi_crc32((const unsigned char *)pgpt_head,
+		le32_to_cpu(pgpt_head->header_size));
+
+	memcpy(&pgpt_head->header_crc32, &crc32_backup, sizeof(crc32_backup));
+
+	if (calc_crc32 != le32_to_cpu(crc32_backup)) {
+		printf("GUID Partition Table Header CRC is wrong:"
+			"0x%x != 0x%x\n",
+		       le32_to_cpu(crc32_backup), calc_crc32);
+		return 0;
+	}
+
+	/* Check that the my_lba entry points to the LBA that contains the GPT */
+	if (le64_to_cpu(pgpt_head->my_lba) != lba) {
+		printf("GPT: my_lba incorrect: %llX != %llX\n",
+			le64_to_cpu(pgpt_head->my_lba),
+			lba);
+		return 0;
+	}
+
+	/* Check the first_usable_lba and last_usable_lba are within the disk. */
+	lastlba = (unsigned long long)dev_desc->lba;
+	if (le64_to_cpu(pgpt_head->first_usable_lba) > lastlba) {
+		printf("GPT: first_usable_lba incorrect: %llX > %llX\n",
+			le64_to_cpu(pgpt_head->first_usable_lba), lastlba);
+		return 0;
+	}
+	if (le64_to_cpu(pgpt_head->last_usable_lba) > lastlba) {
+		printf("GPT: last_usable_lba incorrect: %llX > %llX\n",
+			(u64) le64_to_cpu(pgpt_head->last_usable_lba), lastlba);
+		return 0;
+	}
+
+	debug("GPT: first_usable_lba: %llX last_usable_lba %llX last lba %llX\n",
+		le64_to_cpu(pgpt_head->first_usable_lba),
+		le64_to_cpu(pgpt_head->last_usable_lba), lastlba);
+
+	/* Read and allocate Partition Table Entries */
+	*pgpt_pte = alloc_read_gpt_entries(dev_desc, pgpt_head);
+	if (*pgpt_pte == NULL) {
+		printf("GPT: Failed to allocate memory for PTE\n");
+		return 0;
+	}
+
+	/* Check the GUID Partition Table Entry Array CRC */
+	calc_crc32 = efi_crc32((const unsigned char *)*pgpt_pte,
+		le32_to_cpu(pgpt_head->num_partition_entries) *
+		le32_to_cpu(pgpt_head->sizeof_partition_entry));
+
+	if (calc_crc32 != le32_to_cpu(pgpt_head->partition_entry_array_crc32)) {
+		printf("GUID Partition Table Entry Array CRC is wrong:"
+			"0x%x != 0x%x\n",
+			le32_to_cpu(pgpt_head->partition_entry_array_crc32),
+			calc_crc32);
+
+		free(*pgpt_pte);
+		return 0;
+	}
+
+	/* We're done, all's well */
+	return 1;
+}
+
+/**
+ * alloc_read_gpt_entries(): reads partition entries from disk
+ * @dev_desc
+ * @gpt - GPT header
+ *
+ * Description: Returns ptes on success,  NULL on error.
+ * Allocates space for PTEs based on information found in @gpt.
+ * Notes: remember to free pte when you're done!
+ */
+static gpt_entry *alloc_read_gpt_entries(block_dev_desc_t * dev_desc,
+					 gpt_header * pgpt_head)
+{
+	size_t count = 0, blk_cnt;
+	gpt_entry *pte = NULL;
+
+	if (!dev_desc || !pgpt_head) {
+		printf("%s: Invalid Argument(s)\n", __func__);
+		return NULL;
+	}
+
+	count = le32_to_cpu(pgpt_head->num_partition_entries) *
+		le32_to_cpu(pgpt_head->sizeof_partition_entry);
+
+	debug("%s: count = %u * %u = %zu\n", __func__,
+	      (u32) le32_to_cpu(pgpt_head->num_partition_entries),
+	      (u32) le32_to_cpu(pgpt_head->sizeof_partition_entry), count);
+
+	/* Allocate memory for PTE, remember to FREE */
+	if (count != 0) {
+		pte = memalign(ARCH_DMA_MINALIGN,
+			       PAD_TO_BLOCKSIZE(count, dev_desc));
+	}
+
+	if (count == 0 || pte == NULL) {
+		printf("%s: ERROR: Can't allocate 0x%zX "
+		       "bytes for GPT Entries\n",
+			__func__, count);
+		return NULL;
+	}
+
+	/* Read GPT Entries from device */
+	blk_cnt = BLOCK_CNT(count, dev_desc);
+	if (dev_desc->block_read (dev_desc->dev,
+		le64_to_cpu(pgpt_head->partition_entry_lba),
+		(lbaint_t) (blk_cnt), pte)
+		!= blk_cnt) {
+
+		printf("*** ERROR: Can't read GPT Entries ***\n");
+		free(pte);
+		return NULL;
+	}
+	return pte;
+}
+
+/**
+ * is_pte_valid(): validates a single Partition Table Entry
+ * @gpt_entry - Pointer to a single Partition Table Entry
+ *
+ * Description: returns 1 if valid,  0 on error.
+ */
+static int is_pte_valid(gpt_entry * pte)
+{
+	efi_guid_t unused_guid;
+
+	if (!pte) {
+		printf("%s: Invalid Argument(s)\n", __func__);
+		return 0;
+	}
+
+	/* Only one validation for now:
+	 * The GUID Partition Type != Unused Entry (ALL-ZERO)
+	 */
+	memset(unused_guid.b, 0, sizeof(unused_guid.b));
+
+	if (memcmp(pte->partition_type_guid.b, unused_guid.b,
+		sizeof(unused_guid.b)) == 0) {
+
+		debug("%s: Found an unused PTE GUID at 0x%08X\n", __func__,
+		      (unsigned int)(uintptr_t)pte);
+
+		return 0;
+	} else {
+		return 1;
+	}
+}
+#endif