xref: /rk3399_rockchip-uboot/disk/part_efi.c (revision d0ff3d454829105c81afe7f5d8c79e0d3d18c1a2)
1 /*
2  * Copyright (C) 2008 RuggedCom, Inc.
3  * Richard Retanubun <RichardRetanubun@RuggedCom.com>
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 /*
9  * NOTE:
10  *   when CONFIG_SYS_64BIT_LBA is not defined, lbaint_t is 32 bits; this
11  *   limits the maximum size of addressable storage to < 2 Terra Bytes
12  */
13 #include <asm/unaligned.h>
14 #include <common.h>
15 #include <command.h>
16 #include <fdtdec.h>
17 #include <ide.h>
18 #include <inttypes.h>
19 #include <malloc.h>
20 #include <memalign.h>
21 #include <part_efi.h>
22 #include <linux/compiler.h>
23 #include <linux/ctype.h>
24 
25 DECLARE_GLOBAL_DATA_PTR;
26 
27 #ifdef HAVE_BLOCK_DEVICE
28 /**
29  * efi_crc32() - EFI version of crc32 function
30  * @buf: buffer to calculate crc32 of
31  * @len - length of buf
32  *
33  * Description: Returns EFI-style CRC32 value for @buf
34  */
35 static inline u32 efi_crc32(const void *buf, u32 len)
36 {
37 	return crc32(0, buf, len);
38 }
39 
40 /*
41  * Private function prototypes
42  */
43 
44 static int pmbr_part_valid(struct partition *part);
45 static int is_pmbr_valid(legacy_mbr * mbr);
46 static int is_gpt_valid(struct blk_desc *dev_desc, u64 lba,
47 				gpt_header *pgpt_head, gpt_entry **pgpt_pte);
48 static gpt_entry *alloc_read_gpt_entries(struct blk_desc *dev_desc,
49 					 gpt_header *pgpt_head);
50 static int is_pte_valid(gpt_entry * pte);
51 
52 static char *print_efiname(gpt_entry *pte)
53 {
54 	static char name[PARTNAME_SZ + 1];
55 	int i;
56 	for (i = 0; i < PARTNAME_SZ; i++) {
57 		u8 c;
58 		c = pte->partition_name[i] & 0xff;
59 		c = (c && !isprint(c)) ? '.' : c;
60 		name[i] = c;
61 	}
62 	name[PARTNAME_SZ] = 0;
63 	return name;
64 }
65 
66 static efi_guid_t system_guid = PARTITION_SYSTEM_GUID;
67 
68 static inline int is_bootable(gpt_entry *p)
69 {
70 	return p->attributes.fields.legacy_bios_bootable ||
71 		!memcmp(&(p->partition_type_guid), &system_guid,
72 			sizeof(efi_guid_t));
73 }
74 
75 static int validate_gpt_header(gpt_header *gpt_h, lbaint_t lba,
76 		lbaint_t lastlba)
77 {
78 	uint32_t crc32_backup = 0;
79 	uint32_t calc_crc32;
80 
81 	/* Check the GPT header signature */
82 	if (le64_to_cpu(gpt_h->signature) != GPT_HEADER_SIGNATURE) {
83 		printf("%s signature is wrong: 0x%llX != 0x%llX\n",
84 		       "GUID Partition Table Header",
85 		       le64_to_cpu(gpt_h->signature),
86 		       GPT_HEADER_SIGNATURE);
87 		return -1;
88 	}
89 
90 	/* Check the GUID Partition Table CRC */
91 	memcpy(&crc32_backup, &gpt_h->header_crc32, sizeof(crc32_backup));
92 	memset(&gpt_h->header_crc32, 0, sizeof(gpt_h->header_crc32));
93 
94 	calc_crc32 = efi_crc32((const unsigned char *)gpt_h,
95 		le32_to_cpu(gpt_h->header_size));
96 
97 	memcpy(&gpt_h->header_crc32, &crc32_backup, sizeof(crc32_backup));
98 
99 	if (calc_crc32 != le32_to_cpu(crc32_backup)) {
100 		printf("%s CRC is wrong: 0x%x != 0x%x\n",
101 		       "GUID Partition Table Header",
102 		       le32_to_cpu(crc32_backup), calc_crc32);
103 		return -1;
104 	}
105 
106 	/*
107 	 * Check that the my_lba entry points to the LBA that contains the GPT
108 	 */
109 	if (le64_to_cpu(gpt_h->my_lba) != lba) {
110 		printf("GPT: my_lba incorrect: %llX != " LBAF "\n",
111 		       le64_to_cpu(gpt_h->my_lba),
112 		       lba);
113 		return -1;
114 	}
115 
116 	/*
117 	 * Check that the first_usable_lba and that the last_usable_lba are
118 	 * within the disk.
119 	 */
120 	if (le64_to_cpu(gpt_h->first_usable_lba) > lastlba) {
121 		printf("GPT: first_usable_lba incorrect: %llX > " LBAF "\n",
122 		       le64_to_cpu(gpt_h->first_usable_lba), lastlba);
123 		return -1;
124 	}
125 	if (le64_to_cpu(gpt_h->last_usable_lba) > lastlba) {
126 		printf("GPT: last_usable_lba incorrect: %llX > " LBAF "\n",
127 		       le64_to_cpu(gpt_h->last_usable_lba), lastlba);
128 		return -1;
129 	}
130 
131 	debug("GPT: first_usable_lba: %llX last_usable_lba: %llX last lba: "
132 	      LBAF "\n", le64_to_cpu(gpt_h->first_usable_lba),
133 	      le64_to_cpu(gpt_h->last_usable_lba), lastlba);
134 
135 	return 0;
136 }
137 
138 static int validate_gpt_entries(gpt_header *gpt_h, gpt_entry *gpt_e)
139 {
140 	uint32_t calc_crc32;
141 
142 	/* Check the GUID Partition Table Entry Array CRC */
143 	calc_crc32 = efi_crc32((const unsigned char *)gpt_e,
144 		le32_to_cpu(gpt_h->num_partition_entries) *
145 		le32_to_cpu(gpt_h->sizeof_partition_entry));
146 
147 	if (calc_crc32 != le32_to_cpu(gpt_h->partition_entry_array_crc32)) {
148 		printf("%s: 0x%x != 0x%x\n",
149 		       "GUID Partition Table Entry Array CRC is wrong",
150 		       le32_to_cpu(gpt_h->partition_entry_array_crc32),
151 		       calc_crc32);
152 		return -1;
153 	}
154 
155 	return 0;
156 }
157 
158 static void prepare_backup_gpt_header(gpt_header *gpt_h)
159 {
160 	uint32_t calc_crc32;
161 	uint64_t val;
162 
163 	/* recalculate the values for the Backup GPT Header */
164 	val = le64_to_cpu(gpt_h->my_lba);
165 	gpt_h->my_lba = gpt_h->alternate_lba;
166 	gpt_h->alternate_lba = cpu_to_le64(val);
167 	gpt_h->partition_entry_lba =
168 			cpu_to_le64(le64_to_cpu(gpt_h->last_usable_lba) + 1);
169 	gpt_h->header_crc32 = 0;
170 
171 	calc_crc32 = efi_crc32((const unsigned char *)gpt_h,
172 			       le32_to_cpu(gpt_h->header_size));
173 	gpt_h->header_crc32 = cpu_to_le32(calc_crc32);
174 }
175 
176 #if CONFIG_IS_ENABLED(EFI_PARTITION)
177 /*
178  * Public Functions (include/part.h)
179  */
180 
181 /*
182  * UUID is displayed as 32 hexadecimal digits, in 5 groups,
183  * separated by hyphens, in the form 8-4-4-4-12 for a total of 36 characters
184  */
185 int get_disk_guid(struct blk_desc * dev_desc, char *guid)
186 {
187 	ALLOC_CACHE_ALIGN_BUFFER_PAD(gpt_header, gpt_head, 1, dev_desc->blksz);
188 	gpt_entry *gpt_pte = NULL;
189 	unsigned char *guid_bin;
190 
191 	/* This function validates AND fills in the GPT header and PTE */
192 	if (is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA,
193 			 gpt_head, &gpt_pte) != 1) {
194 		printf("%s: *** ERROR: Invalid GPT ***\n", __func__);
195 		if (is_gpt_valid(dev_desc, dev_desc->lba - 1,
196 				 gpt_head, &gpt_pte) != 1) {
197 			printf("%s: *** ERROR: Invalid Backup GPT ***\n",
198 			       __func__);
199 			return -EINVAL;
200 		} else {
201 			printf("%s: ***        Using Backup GPT ***\n",
202 			       __func__);
203 		}
204 	}
205 
206 	guid_bin = gpt_head->disk_guid.b;
207 	uuid_bin_to_str(guid_bin, guid, UUID_STR_FORMAT_GUID);
208 
209 	return 0;
210 }
211 
212 void part_print_efi(struct blk_desc *dev_desc)
213 {
214 	ALLOC_CACHE_ALIGN_BUFFER_PAD(gpt_header, gpt_head, 1, dev_desc->blksz);
215 	gpt_entry *gpt_pte = NULL;
216 	int i = 0;
217 	char uuid[UUID_STR_LEN + 1];
218 	unsigned char *uuid_bin;
219 
220 	/* This function validates AND fills in the GPT header and PTE */
221 	if (is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA,
222 			 gpt_head, &gpt_pte) != 1) {
223 		printf("%s: *** ERROR: Invalid GPT ***\n", __func__);
224 		if (is_gpt_valid(dev_desc, (dev_desc->lba - 1),
225 				 gpt_head, &gpt_pte) != 1) {
226 			printf("%s: *** ERROR: Invalid Backup GPT ***\n",
227 			       __func__);
228 			return;
229 		} else {
230 			printf("%s: ***        Using Backup GPT ***\n",
231 			       __func__);
232 		}
233 	}
234 
235 	debug("%s: gpt-entry at %p\n", __func__, gpt_pte);
236 
237 	printf("Part\tStart LBA\tEnd LBA\t\tName\n");
238 	printf("\tAttributes\n");
239 	printf("\tType GUID\n");
240 	printf("\tPartition GUID\n");
241 
242 	for (i = 0; i < le32_to_cpu(gpt_head->num_partition_entries); i++) {
243 		/* Stop at the first non valid PTE */
244 		if (!is_pte_valid(&gpt_pte[i]))
245 			break;
246 
247 		printf("%3d\t0x%08llx\t0x%08llx\t\"%s\"\n", (i + 1),
248 			le64_to_cpu(gpt_pte[i].starting_lba),
249 			le64_to_cpu(gpt_pte[i].ending_lba),
250 			print_efiname(&gpt_pte[i]));
251 		printf("\tattrs:\t0x%016llx\n", gpt_pte[i].attributes.raw);
252 		uuid_bin = (unsigned char *)gpt_pte[i].partition_type_guid.b;
253 		uuid_bin_to_str(uuid_bin, uuid, UUID_STR_FORMAT_GUID);
254 		printf("\ttype:\t%s\n", uuid);
255 #ifdef CONFIG_PARTITION_TYPE_GUID
256 		if (!uuid_guid_get_str(uuid_bin, uuid))
257 			printf("\ttype:\t%s\n", uuid);
258 #endif
259 		uuid_bin = (unsigned char *)gpt_pte[i].unique_partition_guid.b;
260 		uuid_bin_to_str(uuid_bin, uuid, UUID_STR_FORMAT_GUID);
261 		printf("\tguid:\t%s\n", uuid);
262 	}
263 
264 	/* Remember to free pte */
265 	free(gpt_pte);
266 	return;
267 }
268 
269 int part_get_info_efi(struct blk_desc *dev_desc, int part,
270 		      disk_partition_t *info)
271 {
272 	static gpt_entry *gpt_pte = NULL;
273 	static gpt_header *gpt_head = NULL;
274 
275 	if (!gpt_head)
276 		gpt_head = memalign(ARCH_DMA_MINALIGN, dev_desc->blksz);
277 
278 	/*
279 	 * We suppose different dev have different size, eg. emmc vs sd
280 	 * free the pte first if exist and then will malloc and init a new one.
281 	 */
282 	if (gpt_head && (gpt_head->last_usable_lba + 0x22) != dev_desc->lba) {
283 		if (gpt_pte)
284 			free(gpt_pte);
285 		gpt_pte = NULL;
286 	}
287 
288 	/* "part" argument must be at least 1 */
289 	if (part < 1) {
290 		printf("%s: Invalid Argument(s)\n", __func__);
291 		return -1;
292 	}
293 
294 	/* This function validates AND fills in the GPT header and PTE */
295 	if (is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA,
296 			gpt_head, &gpt_pte) != 1) {
297 		printf("%s: *** ERROR: Invalid GPT ***\n", __func__);
298 		if (is_gpt_valid(dev_desc, (dev_desc->lba - 1),
299 				 gpt_head, &gpt_pte) != 1) {
300 			printf("%s: *** ERROR: Invalid Backup GPT ***\n",
301 			       __func__);
302 			return -1;
303 		} else {
304 			printf("%s: ***        Using Backup GPT ***\n",
305 			       __func__);
306 		}
307 	}
308 
309 	if (part > le32_to_cpu(gpt_head->num_partition_entries) ||
310 	    !is_pte_valid(&gpt_pte[part - 1])) {
311 		debug("%s: *** ERROR: Invalid partition number %d ***\n",
312 			__func__, part);
313 		return -1;
314 	}
315 
316 	/* The 'lbaint_t' casting may limit the maximum disk size to 2 TB */
317 	info->start = (lbaint_t)le64_to_cpu(gpt_pte[part - 1].starting_lba);
318 	/* The ending LBA is inclusive, to calculate size, add 1 to it */
319 	info->size = (lbaint_t)le64_to_cpu(gpt_pte[part - 1].ending_lba) + 1
320 		     - info->start;
321 	info->blksz = dev_desc->blksz;
322 
323 	sprintf((char *)info->name, "%s",
324 			print_efiname(&gpt_pte[part - 1]));
325 	strcpy((char *)info->type, "U-Boot");
326 	info->bootable = is_bootable(&gpt_pte[part - 1]);
327 #if CONFIG_IS_ENABLED(PARTITION_UUIDS)
328 	uuid_bin_to_str(gpt_pte[part - 1].unique_partition_guid.b, info->uuid,
329 			UUID_STR_FORMAT_GUID);
330 #endif
331 #ifdef CONFIG_PARTITION_TYPE_GUID
332 	uuid_bin_to_str(gpt_pte[part - 1].partition_type_guid.b,
333 			info->type_guid, UUID_STR_FORMAT_GUID);
334 #endif
335 
336 	debug("%s: start 0x" LBAF ", size 0x" LBAF ", name %s\n", __func__,
337 	      info->start, info->size, info->name);
338 
339 	return 0;
340 }
341 
342 #ifdef CONFIG_RKIMG_BOOTLOADER
343 static void gpt_entry_modify(struct blk_desc *dev_desc,
344 			     gpt_entry *gpt_pte,
345 			     gpt_header *gpt_head)
346 {
347 	int i;
348 	uint32_t calc_crc32;
349 
350 	for (i = 0; i < gpt_head->num_partition_entries; i++) {
351 		if (!is_pte_valid(&gpt_pte[i]))
352 			break;
353 	}
354 
355 	if (gpt_pte[i - 1].ending_lba <= (dev_desc->lba - 0x22))
356 		return;
357 
358 	gpt_pte[i - 1].ending_lba = dev_desc->lba - 0x22;
359 	calc_crc32 = efi_crc32((const unsigned char *)gpt_pte,
360 			       le32_to_cpu(gpt_head->num_partition_entries) *
361 			       le32_to_cpu(gpt_head->sizeof_partition_entry));
362 	gpt_head->partition_entry_array_crc32 = calc_crc32;
363 }
364 
365 static int part_efi_repair(struct blk_desc *dev_desc, gpt_entry *gpt_pte,
366 			   gpt_header *gpt_head, int head_gpt_valid,
367 			   int backup_gpt_valid)
368 {
369 	uint32_t calc_crc32;
370 	size_t count = 0, blk_cnt;
371 	lbaint_t blk;
372 
373 	if (head_gpt_valid == 1 && backup_gpt_valid == 1) {
374 		return 0;
375 	} else if (head_gpt_valid == 0 && backup_gpt_valid == 0) {
376 		return -1;
377 	} else if (head_gpt_valid == 1 && backup_gpt_valid == 0) {
378 		gpt_head->header_crc32 = 0;
379 		gpt_head->my_lba = dev_desc->lba - 1;
380 		gpt_head->alternate_lba = 1;
381 		gpt_head->partition_entry_lba = dev_desc->lba - 0x21;
382 		gpt_entry_modify(dev_desc, gpt_pte, gpt_head);
383 		calc_crc32 = efi_crc32((const unsigned char *)gpt_head,
384 				       le32_to_cpu(gpt_head->header_size));
385 		gpt_head->header_crc32 = calc_crc32;
386 		if (blk_dwrite(dev_desc, dev_desc->lba - 1, 1, gpt_head) != 1) {
387 			printf("*** ERROR: Can't write GPT header ***\n");
388 			return -1;
389 		}
390 		count = le32_to_cpu(gpt_head->num_partition_entries) *
391 			le32_to_cpu(gpt_head->sizeof_partition_entry);
392 		blk = le64_to_cpu(gpt_head->partition_entry_lba);
393 		blk_cnt = BLOCK_CNT(count, dev_desc);
394 		if (blk_dwrite(dev_desc, blk, (lbaint_t)blk_cnt, gpt_pte) !=
395 		    blk_cnt) {
396 			printf("*** ERROR: Can't write entry partitions ***\n");
397 			return -1;
398 		}
399 		printf("Repair the backup gpt table OK!\n");
400 	} else if (head_gpt_valid == 0 && backup_gpt_valid == 1) {
401 		gpt_head->header_crc32 = 0;
402 		gpt_head->my_lba = 1;
403 		gpt_head->alternate_lba = dev_desc->lba - 1;
404 		gpt_head->partition_entry_lba = 0x22;
405 		gpt_entry_modify(dev_desc, gpt_pte, gpt_head);
406 		calc_crc32 = efi_crc32((const unsigned char *)gpt_head,
407 				       le32_to_cpu(gpt_head->header_size));
408 		gpt_head->header_crc32 = calc_crc32;
409 		if (blk_dwrite(dev_desc, 1, 1, gpt_head) != 1) {
410 			printf("*** ERROR: Can't write GPT header ***\n");
411 			return -1;
412 		}
413 		count = le32_to_cpu(gpt_head->num_partition_entries) *
414 			le32_to_cpu(gpt_head->sizeof_partition_entry);
415 		blk = le64_to_cpu(gpt_head->partition_entry_lba);
416 		blk_cnt = BLOCK_CNT(count, dev_desc);
417 		if (blk_dwrite(dev_desc, blk, (lbaint_t)blk_cnt, gpt_pte) !=
418 		    blk_cnt) {
419 			printf("*** ERROR: Can't write entry partitions ***\n");
420 			return -1;
421 		}
422 		printf("Repair the Primary gpt table OK!\n");
423 	}
424 
425 	return 0;
426 }
427 #endif
428 
429 static int part_test_efi(struct blk_desc *dev_desc)
430 {
431 	ALLOC_CACHE_ALIGN_BUFFER_PAD(legacy_mbr, legacymbr, 1, dev_desc->blksz);
432 	int ret = 0;
433 
434 	/* Read legacy MBR from block 0 and validate it */
435 	if ((blk_dread(dev_desc, 0, 1, (ulong *)legacymbr) != 1)
436 		|| (is_pmbr_valid(legacymbr) != 1)) {
437 		return -1;
438 	}
439 #ifdef CONFIG_RKIMG_BOOTLOADER
440 	gpt_entry *h_gpt_pte = NULL;
441 	gpt_header *h_gpt_head = NULL;
442 	gpt_entry *b_gpt_pte = NULL;
443 	gpt_header *b_gpt_head = NULL;
444 	int head_gpt_valid = 0;
445 	int backup_gpt_valid = 0;
446 
447 	if (!h_gpt_head)
448 		h_gpt_head = memalign(ARCH_DMA_MINALIGN, dev_desc->blksz);
449 	if (!b_gpt_head)
450 		b_gpt_head = memalign(ARCH_DMA_MINALIGN, dev_desc->blksz);
451 
452 	head_gpt_valid = is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA,
453 				      h_gpt_head, &h_gpt_pte);
454 	backup_gpt_valid = is_gpt_valid(dev_desc, (dev_desc->lba - 1),
455 					b_gpt_head, &b_gpt_pte);
456 	if (head_gpt_valid == 1 && backup_gpt_valid == 0) {
457 		if (part_efi_repair(dev_desc, h_gpt_pte, h_gpt_head,
458 				    head_gpt_valid, backup_gpt_valid))
459 			printf("Backup GPT repair fail!\n");
460 	} else if (head_gpt_valid == 0 && backup_gpt_valid == 1) {
461 		if (part_efi_repair(dev_desc, b_gpt_pte, b_gpt_head,
462 				    head_gpt_valid, backup_gpt_valid))
463 			printf("Primary GPT repair fail!\n");
464 	} else if (head_gpt_valid == 0 && backup_gpt_valid == 0) {
465 		ret = -1;
466 	}
467 
468 	free(h_gpt_pte);
469 	h_gpt_pte = NULL;
470 	free(h_gpt_head);
471 	h_gpt_head = NULL;
472 	free(b_gpt_pte);
473 	b_gpt_pte = NULL;
474 	free(b_gpt_head);
475 	b_gpt_head = NULL;
476 #endif
477 	return ret;
478 }
479 
480 /**
481  * set_protective_mbr(): Set the EFI protective MBR
482  * @param dev_desc - block device descriptor
483  *
484  * @return - zero on success, otherwise error
485  */
486 static int set_protective_mbr(struct blk_desc *dev_desc)
487 {
488 	/* Setup the Protective MBR */
489 	ALLOC_CACHE_ALIGN_BUFFER(legacy_mbr, p_mbr, 1);
490 	memset(p_mbr, 0, sizeof(*p_mbr));
491 
492 	if (p_mbr == NULL) {
493 		printf("%s: calloc failed!\n", __func__);
494 		return -1;
495 	}
496 
497 	/* Read MBR to backup boot code if it exists */
498 	if (blk_dread(dev_desc, 0, 1, p_mbr) != 1) {
499 		pr_err("** Can't read from device %d **\n", dev_desc->devnum);
500 		return -1;
501 	}
502 
503 	/* Append signature */
504 	p_mbr->signature = MSDOS_MBR_SIGNATURE;
505 	p_mbr->partition_record[0].sys_ind = EFI_PMBR_OSTYPE_EFI_GPT;
506 	p_mbr->partition_record[0].start_sect = 1;
507 	p_mbr->partition_record[0].nr_sects = (u32) dev_desc->lba - 1;
508 
509 	/* Write MBR sector to the MMC device */
510 	if (blk_dwrite(dev_desc, 0, 1, p_mbr) != 1) {
511 		printf("** Can't write to device %d **\n",
512 			dev_desc->devnum);
513 		return -1;
514 	}
515 
516 	return 0;
517 }
518 
519 int write_gpt_table(struct blk_desc *dev_desc,
520 		gpt_header *gpt_h, gpt_entry *gpt_e)
521 {
522 	const int pte_blk_cnt = BLOCK_CNT((gpt_h->num_partition_entries
523 					   * sizeof(gpt_entry)), dev_desc);
524 	u32 calc_crc32;
525 
526 	debug("max lba: %x\n", (u32) dev_desc->lba);
527 	/* Setup the Protective MBR */
528 	if (set_protective_mbr(dev_desc) < 0)
529 		goto err;
530 
531 	/* Generate CRC for the Primary GPT Header */
532 	calc_crc32 = efi_crc32((const unsigned char *)gpt_e,
533 			      le32_to_cpu(gpt_h->num_partition_entries) *
534 			      le32_to_cpu(gpt_h->sizeof_partition_entry));
535 	gpt_h->partition_entry_array_crc32 = cpu_to_le32(calc_crc32);
536 
537 	calc_crc32 = efi_crc32((const unsigned char *)gpt_h,
538 			      le32_to_cpu(gpt_h->header_size));
539 	gpt_h->header_crc32 = cpu_to_le32(calc_crc32);
540 
541 	/* Write the First GPT to the block right after the Legacy MBR */
542 	if (blk_dwrite(dev_desc, 1, 1, gpt_h) != 1)
543 		goto err;
544 
545 	if (blk_dwrite(dev_desc, le64_to_cpu(gpt_h->partition_entry_lba),
546 		       pte_blk_cnt, gpt_e) != pte_blk_cnt)
547 		goto err;
548 
549 	prepare_backup_gpt_header(gpt_h);
550 
551 	if (blk_dwrite(dev_desc, (lbaint_t)le64_to_cpu(gpt_h->last_usable_lba)
552 		       + 1, pte_blk_cnt, gpt_e) != pte_blk_cnt)
553 		goto err;
554 
555 	if (blk_dwrite(dev_desc, (lbaint_t)le64_to_cpu(gpt_h->my_lba), 1,
556 		       gpt_h) != 1)
557 		goto err;
558 
559 	debug("GPT successfully written to block device!\n");
560 	return 0;
561 
562  err:
563 	printf("** Can't write to device %d **\n", dev_desc->devnum);
564 	return -1;
565 }
566 
567 int gpt_fill_pte(struct blk_desc *dev_desc,
568 		 gpt_header *gpt_h, gpt_entry *gpt_e,
569 		 disk_partition_t *partitions, int parts)
570 {
571 	lbaint_t offset = (lbaint_t)le64_to_cpu(gpt_h->first_usable_lba);
572 	lbaint_t last_usable_lba = (lbaint_t)
573 			le64_to_cpu(gpt_h->last_usable_lba);
574 	int i, k;
575 	size_t efiname_len, dosname_len;
576 #if CONFIG_IS_ENABLED(PARTITION_UUIDS)
577 	char *str_uuid;
578 	unsigned char *bin_uuid;
579 #endif
580 #ifdef CONFIG_PARTITION_TYPE_GUID
581 	char *str_type_guid;
582 	unsigned char *bin_type_guid;
583 #endif
584 	size_t hdr_start = gpt_h->my_lba;
585 	size_t hdr_end = hdr_start + 1;
586 
587 	size_t pte_start = gpt_h->partition_entry_lba;
588 	size_t pte_end = pte_start +
589 		gpt_h->num_partition_entries * gpt_h->sizeof_partition_entry /
590 		dev_desc->blksz;
591 
592 	for (i = 0; i < parts; i++) {
593 		/* partition starting lba */
594 		lbaint_t start = partitions[i].start;
595 		lbaint_t size = partitions[i].size;
596 
597 		if (start) {
598 			offset = start + size;
599 		} else {
600 			start = offset;
601 			offset += size;
602 		}
603 
604 		/*
605 		 * If our partition overlaps with either the GPT
606 		 * header, or the partition entry, reject it.
607 		 */
608 		if (((start < hdr_end && hdr_start < (start + size)) ||
609 		     (start < pte_end && pte_start < (start + size)))) {
610 			printf("Partition overlap\n");
611 			return -1;
612 		}
613 
614 		gpt_e[i].starting_lba = cpu_to_le64(start);
615 
616 		if (offset > (last_usable_lba + 1)) {
617 			printf("Partitions layout exceds disk size\n");
618 			return -1;
619 		}
620 		/* partition ending lba */
621 		if ((i == parts - 1) && (size == 0))
622 			/* extend the last partition to maximuim */
623 			gpt_e[i].ending_lba = gpt_h->last_usable_lba;
624 		else
625 			gpt_e[i].ending_lba = cpu_to_le64(offset - 1);
626 
627 #ifdef CONFIG_PARTITION_TYPE_GUID
628 		str_type_guid = partitions[i].type_guid;
629 		bin_type_guid = gpt_e[i].partition_type_guid.b;
630 		if (strlen(str_type_guid)) {
631 			if (uuid_str_to_bin(str_type_guid, bin_type_guid,
632 					    UUID_STR_FORMAT_GUID)) {
633 				printf("Partition no. %d: invalid type guid: %s\n",
634 				       i, str_type_guid);
635 				return -1;
636 			}
637 		} else {
638 			/* default partition type GUID */
639 			memcpy(bin_type_guid,
640 			       &PARTITION_BASIC_DATA_GUID, 16);
641 		}
642 #else
643 		/* partition type GUID */
644 		memcpy(gpt_e[i].partition_type_guid.b,
645 			&PARTITION_BASIC_DATA_GUID, 16);
646 #endif
647 
648 #if CONFIG_IS_ENABLED(PARTITION_UUIDS)
649 		str_uuid = partitions[i].uuid;
650 		bin_uuid = gpt_e[i].unique_partition_guid.b;
651 
652 		if (uuid_str_to_bin(str_uuid, bin_uuid, UUID_STR_FORMAT_GUID)) {
653 			printf("Partition no. %d: invalid guid: %s\n",
654 				i, str_uuid);
655 			return -1;
656 		}
657 #endif
658 
659 		/* partition attributes */
660 		memset(&gpt_e[i].attributes, 0,
661 		       sizeof(gpt_entry_attributes));
662 
663 		if (partitions[i].bootable)
664 			gpt_e[i].attributes.fields.legacy_bios_bootable = 1;
665 
666 		/* partition name */
667 		efiname_len = sizeof(gpt_e[i].partition_name)
668 			/ sizeof(efi_char16_t);
669 		dosname_len = sizeof(partitions[i].name);
670 
671 		memset(gpt_e[i].partition_name, 0,
672 		       sizeof(gpt_e[i].partition_name));
673 
674 		for (k = 0; k < min(dosname_len, efiname_len); k++)
675 			gpt_e[i].partition_name[k] =
676 				(efi_char16_t)(partitions[i].name[k]);
677 
678 		debug("%s: name: %s offset[%d]: 0x" LBAF
679 		      " size[%d]: 0x" LBAF "\n",
680 		      __func__, partitions[i].name, i,
681 		      offset, i, size);
682 	}
683 
684 	return 0;
685 }
686 
687 static uint32_t partition_entries_offset(struct blk_desc *dev_desc)
688 {
689 	uint32_t offset_blks = 2;
690 	uint32_t __maybe_unused offset_bytes;
691 	int __maybe_unused config_offset;
692 
693 #if defined(CONFIG_EFI_PARTITION_ENTRIES_OFF)
694 	/*
695 	 * Some architectures require their SPL loader at a fixed
696 	 * address within the first 16KB of the disk.  To avoid an
697 	 * overlap with the partition entries of the EFI partition
698 	 * table, the first safe offset (in bytes, from the start of
699 	 * the disk) for the entries can be set in
700 	 * CONFIG_EFI_PARTITION_ENTRIES_OFF.
701 	 */
702 	offset_bytes =
703 		PAD_TO_BLOCKSIZE(CONFIG_EFI_PARTITION_ENTRIES_OFF, dev_desc);
704 	offset_blks = offset_bytes / dev_desc->blksz;
705 #endif
706 
707 #if defined(CONFIG_OF_CONTROL)
708 	/*
709 	 * Allow the offset of the first partition entires (in bytes
710 	 * from the start of the device) to be specified as a property
711 	 * of the device tree '/config' node.
712 	 */
713 	config_offset = fdtdec_get_config_int(gd->fdt_blob,
714 					      "u-boot,efi-partition-entries-offset",
715 					      -EINVAL);
716 	if (config_offset != -EINVAL) {
717 		offset_bytes = PAD_TO_BLOCKSIZE(config_offset, dev_desc);
718 		offset_blks = offset_bytes / dev_desc->blksz;
719 	}
720 #endif
721 
722 	debug("efi: partition entries offset (in blocks): %d\n", offset_blks);
723 
724 	/*
725 	 * The earliest LBA this can be at is LBA#2 (i.e. right behind
726 	 * the (protective) MBR and the GPT header.
727 	 */
728 	if (offset_blks < 2)
729 		offset_blks = 2;
730 
731 	return offset_blks;
732 }
733 
734 int gpt_fill_header(struct blk_desc *dev_desc, gpt_header *gpt_h,
735 		char *str_guid, int parts_count)
736 {
737 	gpt_h->signature = cpu_to_le64(GPT_HEADER_SIGNATURE);
738 	gpt_h->revision = cpu_to_le32(GPT_HEADER_REVISION_V1);
739 	gpt_h->header_size = cpu_to_le32(sizeof(gpt_header));
740 	gpt_h->my_lba = cpu_to_le64(1);
741 	gpt_h->alternate_lba = cpu_to_le64(dev_desc->lba - 1);
742 	gpt_h->last_usable_lba = cpu_to_le64(dev_desc->lba - 34);
743 	gpt_h->partition_entry_lba =
744 		cpu_to_le64(partition_entries_offset(dev_desc));
745 	gpt_h->first_usable_lba =
746 		cpu_to_le64(le64_to_cpu(gpt_h->partition_entry_lba) + 32);
747 	gpt_h->num_partition_entries = cpu_to_le32(GPT_ENTRY_NUMBERS);
748 	gpt_h->sizeof_partition_entry = cpu_to_le32(sizeof(gpt_entry));
749 	gpt_h->header_crc32 = 0;
750 	gpt_h->partition_entry_array_crc32 = 0;
751 
752 	if (uuid_str_to_bin(str_guid, gpt_h->disk_guid.b, UUID_STR_FORMAT_GUID))
753 		return -1;
754 
755 	return 0;
756 }
757 
758 int gpt_restore(struct blk_desc *dev_desc, char *str_disk_guid,
759 		disk_partition_t *partitions, int parts_count)
760 {
761 	gpt_header *gpt_h;
762 	gpt_entry *gpt_e;
763 	int ret, size;
764 
765 	size = PAD_TO_BLOCKSIZE(sizeof(gpt_header), dev_desc);
766 	gpt_h = malloc_cache_aligned(size);
767 	if (gpt_h == NULL) {
768 		printf("%s: calloc failed!\n", __func__);
769 		return -1;
770 	}
771 	memset(gpt_h, 0, size);
772 
773 	size = PAD_TO_BLOCKSIZE(GPT_ENTRY_NUMBERS * sizeof(gpt_entry),
774 				dev_desc);
775 	gpt_e = malloc_cache_aligned(size);
776 	if (gpt_e == NULL) {
777 		printf("%s: calloc failed!\n", __func__);
778 		free(gpt_h);
779 		return -1;
780 	}
781 	memset(gpt_e, 0, size);
782 
783 	/* Generate Primary GPT header (LBA1) */
784 	ret = gpt_fill_header(dev_desc, gpt_h, str_disk_guid, parts_count);
785 	if (ret)
786 		goto err;
787 
788 	/* Generate partition entries */
789 	ret = gpt_fill_pte(dev_desc, gpt_h, gpt_e, partitions, parts_count);
790 	if (ret)
791 		goto err;
792 
793 	/* Write GPT partition table */
794 	ret = write_gpt_table(dev_desc, gpt_h, gpt_e);
795 
796 err:
797 	free(gpt_e);
798 	free(gpt_h);
799 	return ret;
800 }
801 
802 static void gpt_convert_efi_name_to_char(char *s, efi_char16_t *es, int n)
803 {
804 	char *ess = (char *)es;
805 	int i, j;
806 
807 	memset(s, '\0', n);
808 
809 	for (i = 0, j = 0; j < n; i += 2, j++) {
810 		s[j] = ess[i];
811 		if (!ess[i])
812 			return;
813 	}
814 }
815 
816 int gpt_verify_headers(struct blk_desc *dev_desc, gpt_header *gpt_head,
817 		       gpt_entry **gpt_pte)
818 {
819 	/*
820 	 * This function validates AND
821 	 * fills in the GPT header and PTE
822 	 */
823 	if (is_gpt_valid(dev_desc,
824 			 GPT_PRIMARY_PARTITION_TABLE_LBA,
825 			 gpt_head, gpt_pte) != 1) {
826 		printf("%s: *** ERROR: Invalid GPT ***\n",
827 		       __func__);
828 		return -1;
829 	}
830 	if (is_gpt_valid(dev_desc, (dev_desc->lba - 1),
831 			 gpt_head, gpt_pte) != 1) {
832 		printf("%s: *** ERROR: Invalid Backup GPT ***\n",
833 		       __func__);
834 		return -1;
835 	}
836 
837 	return 0;
838 }
839 
840 int gpt_verify_partitions(struct blk_desc *dev_desc,
841 			  disk_partition_t *partitions, int parts,
842 			  gpt_header *gpt_head, gpt_entry **gpt_pte)
843 {
844 	char efi_str[PARTNAME_SZ + 1];
845 	u64 gpt_part_size;
846 	gpt_entry *gpt_e;
847 	int ret, i;
848 
849 	ret = gpt_verify_headers(dev_desc, gpt_head, gpt_pte);
850 	if (ret)
851 		return ret;
852 
853 	gpt_e = *gpt_pte;
854 
855 	for (i = 0; i < parts; i++) {
856 		if (i == gpt_head->num_partition_entries) {
857 			pr_err("More partitions than allowed!\n");
858 			return -1;
859 		}
860 
861 		/* Check if GPT and ENV partition names match */
862 		gpt_convert_efi_name_to_char(efi_str, gpt_e[i].partition_name,
863 					     PARTNAME_SZ + 1);
864 
865 		debug("%s: part: %2d name - GPT: %16s, ENV: %16s ",
866 		      __func__, i, efi_str, partitions[i].name);
867 
868 		if (strncmp(efi_str, (char *)partitions[i].name,
869 			    sizeof(partitions->name))) {
870 			pr_err("Partition name: %s does not match %s!\n",
871 			      efi_str, (char *)partitions[i].name);
872 			return -1;
873 		}
874 
875 		/* Check if GPT and ENV sizes match */
876 		gpt_part_size = le64_to_cpu(gpt_e[i].ending_lba) -
877 			le64_to_cpu(gpt_e[i].starting_lba) + 1;
878 		debug("size(LBA) - GPT: %8llu, ENV: %8llu ",
879 		      (unsigned long long)gpt_part_size,
880 		      (unsigned long long)partitions[i].size);
881 
882 		if (le64_to_cpu(gpt_part_size) != partitions[i].size) {
883 			/* We do not check the extend partition size */
884 			if ((i == parts - 1) && (partitions[i].size == 0))
885 				continue;
886 
887 			pr_err("Partition %s size: %llu does not match %llu!\n",
888 			      efi_str, (unsigned long long)gpt_part_size,
889 			      (unsigned long long)partitions[i].size);
890 			return -1;
891 		}
892 
893 		/*
894 		 * Start address is optional - check only if provided
895 		 * in '$partition' variable
896 		 */
897 		if (!partitions[i].start) {
898 			debug("\n");
899 			continue;
900 		}
901 
902 		/* Check if GPT and ENV start LBAs match */
903 		debug("start LBA - GPT: %8llu, ENV: %8llu\n",
904 		      le64_to_cpu(gpt_e[i].starting_lba),
905 		      (unsigned long long)partitions[i].start);
906 
907 		if (le64_to_cpu(gpt_e[i].starting_lba) != partitions[i].start) {
908 			pr_err("Partition %s start: %llu does not match %llu!\n",
909 			      efi_str, le64_to_cpu(gpt_e[i].starting_lba),
910 			      (unsigned long long)partitions[i].start);
911 			return -1;
912 		}
913 	}
914 
915 	return 0;
916 }
917 
918 int is_valid_gpt_buf(struct blk_desc *dev_desc, void *buf)
919 {
920 	gpt_header *gpt_h;
921 	gpt_entry *gpt_e;
922 
923 	/* determine start of GPT Header in the buffer */
924 	gpt_h = buf + (GPT_PRIMARY_PARTITION_TABLE_LBA *
925 		       dev_desc->blksz);
926 
927 	if ((le64_to_cpu(gpt_h->alternate_lba) + 1)
928 			!= cpu_to_le64(dev_desc->lba)) {
929 		printf("%s: failed checking '%s'\n", __func__,
930 		       "invalid GPT Disk Size");
931 		return -1;
932 	}
933 
934 	if (validate_gpt_header(gpt_h, GPT_PRIMARY_PARTITION_TABLE_LBA,
935 				dev_desc->lba))
936 		return -1;
937 
938 	/* determine start of GPT Entries in the buffer */
939 	gpt_e = buf + (le64_to_cpu(gpt_h->partition_entry_lba) *
940 		       dev_desc->blksz);
941 	if (validate_gpt_entries(gpt_h, gpt_e))
942 		return -1;
943 
944 	return 0;
945 }
946 
947 int write_mbr_and_gpt_partitions(struct blk_desc *dev_desc, void *buf)
948 {
949 	gpt_header *gpt_h;
950 	gpt_entry *gpt_e;
951 	int gpt_e_blk_cnt;
952 	lbaint_t lba;
953 	int cnt;
954 
955 	if (is_valid_gpt_buf(dev_desc, buf))
956 		return -1;
957 
958 	/* determine start of GPT Header in the buffer */
959 	gpt_h = buf + (GPT_PRIMARY_PARTITION_TABLE_LBA *
960 		       dev_desc->blksz);
961 
962 	/* determine start of GPT Entries in the buffer */
963 	gpt_e = buf + (le64_to_cpu(gpt_h->partition_entry_lba) *
964 		       dev_desc->blksz);
965 	gpt_e_blk_cnt = BLOCK_CNT((le32_to_cpu(gpt_h->num_partition_entries) *
966 				   le32_to_cpu(gpt_h->sizeof_partition_entry)),
967 				  dev_desc);
968 
969 	/* write MBR */
970 	lba = 0;	/* MBR is always at 0 */
971 	cnt = 1;	/* MBR (1 block) */
972 	if (blk_dwrite(dev_desc, lba, cnt, buf) != cnt) {
973 		printf("%s: failed writing '%s' (%d blks at 0x" LBAF ")\n",
974 		       __func__, "MBR", cnt, lba);
975 		return 1;
976 	}
977 
978 	/* write Primary GPT */
979 	lba = GPT_PRIMARY_PARTITION_TABLE_LBA;
980 	cnt = 1;	/* GPT Header (1 block) */
981 	if (blk_dwrite(dev_desc, lba, cnt, gpt_h) != cnt) {
982 		printf("%s: failed writing '%s' (%d blks at 0x" LBAF ")\n",
983 		       __func__, "Primary GPT Header", cnt, lba);
984 		return 1;
985 	}
986 
987 	lba = le64_to_cpu(gpt_h->partition_entry_lba);
988 	cnt = gpt_e_blk_cnt;
989 	if (blk_dwrite(dev_desc, lba, cnt, gpt_e) != cnt) {
990 		printf("%s: failed writing '%s' (%d blks at 0x" LBAF ")\n",
991 		       __func__, "Primary GPT Entries", cnt, lba);
992 		return 1;
993 	}
994 
995 	prepare_backup_gpt_header(gpt_h);
996 
997 	/* write Backup GPT */
998 	lba = le64_to_cpu(gpt_h->partition_entry_lba);
999 	cnt = gpt_e_blk_cnt;
1000 	if (blk_dwrite(dev_desc, lba, cnt, gpt_e) != cnt) {
1001 		printf("%s: failed writing '%s' (%d blks at 0x" LBAF ")\n",
1002 		       __func__, "Backup GPT Entries", cnt, lba);
1003 		return 1;
1004 	}
1005 
1006 	lba = le64_to_cpu(gpt_h->my_lba);
1007 	cnt = 1;	/* GPT Header (1 block) */
1008 	if (blk_dwrite(dev_desc, lba, cnt, gpt_h) != cnt) {
1009 		printf("%s: failed writing '%s' (%d blks at 0x" LBAF ")\n",
1010 		       __func__, "Backup GPT Header", cnt, lba);
1011 		return 1;
1012 	}
1013 
1014 	return 0;
1015 }
1016 #endif
1017 
1018 /*
1019  * Private functions
1020  */
1021 /*
1022  * pmbr_part_valid(): Check for EFI partition signature
1023  *
1024  * Returns: 1 if EFI GPT partition type is found.
1025  */
1026 static int pmbr_part_valid(struct partition *part)
1027 {
1028 	if (part->sys_ind == EFI_PMBR_OSTYPE_EFI_GPT &&
1029 		get_unaligned_le32(&part->start_sect) == 1UL) {
1030 		return 1;
1031 	}
1032 
1033 	return 0;
1034 }
1035 
1036 /*
1037  * is_pmbr_valid(): test Protective MBR for validity
1038  *
1039  * Returns: 1 if PMBR is valid, 0 otherwise.
1040  * Validity depends on two things:
1041  *  1) MSDOS signature is in the last two bytes of the MBR
1042  *  2) One partition of type 0xEE is found, checked by pmbr_part_valid()
1043  */
1044 static int is_pmbr_valid(legacy_mbr * mbr)
1045 {
1046 	int i = 0;
1047 
1048 	if (!mbr || le16_to_cpu(mbr->signature) != MSDOS_MBR_SIGNATURE)
1049 		return 0;
1050 
1051 #ifdef CONFIG_ARCH_ROCKCHIP
1052 	/*
1053 	 * In sd-update card, we use RKPARM partition in bootloader to load
1054 	 * firmware, and use MS-DOS partition in recovery to update system.
1055 	 * Now, we want to use gpt in bootloader and abandon the RKPARM
1056 	 * partition. So in new sd-update card, we write the MS-DOS partition
1057 	 * table and gpt to sd card. Then we must return 1 directly when test
1058 	 * the mbr sector otherwise the gpt is unavailable.
1059 	 */
1060 	return 1;
1061 #endif
1062 	for (i = 0; i < 4; i++) {
1063 		if (pmbr_part_valid(&mbr->partition_record[i])) {
1064 			return 1;
1065 		}
1066 	}
1067 	return 0;
1068 }
1069 
1070 /**
1071  * is_gpt_valid() - tests one GPT header and PTEs for validity
1072  *
1073  * lba is the logical block address of the GPT header to test
1074  * gpt is a GPT header ptr, filled on return.
1075  * ptes is a PTEs ptr, filled on return.
1076  *
1077  * Description: returns 1 if valid,  0 on error.
1078  * If valid, returns pointers to PTEs.
1079  */
1080 static int is_gpt_valid(struct blk_desc *dev_desc, u64 lba,
1081 			gpt_header *pgpt_head, gpt_entry **pgpt_pte)
1082 {
1083 	/* Confirm valid arguments prior to allocation. */
1084 	if (!dev_desc || !pgpt_head) {
1085 		printf("%s: Invalid Argument(s)\n", __func__);
1086 		return 0;
1087 	}
1088 
1089 	/* Re-use pte if it's not NULL */
1090 	if (*pgpt_pte)
1091 		return 1;
1092 
1093 	ALLOC_CACHE_ALIGN_BUFFER(legacy_mbr, mbr, dev_desc->blksz);
1094 
1095 	/* Read MBR Header from device */
1096 	if (blk_dread(dev_desc, 0, 1, (ulong *)mbr) != 1) {
1097 		printf("*** ERROR: Can't read MBR header ***\n");
1098 		return 0;
1099 	}
1100 
1101 	/* Read GPT Header from device */
1102 	if (blk_dread(dev_desc, (lbaint_t)lba, 1, pgpt_head) != 1) {
1103 		printf("*** ERROR: Can't read GPT header ***\n");
1104 		return 0;
1105 	}
1106 
1107 	if (validate_gpt_header(pgpt_head, (lbaint_t)lba, dev_desc->lba))
1108 		return 0;
1109 
1110 	if (dev_desc->sig_type == SIG_TYPE_NONE) {
1111 		efi_guid_t empty = {};
1112 		if (memcmp(&pgpt_head->disk_guid, &empty, sizeof(empty))) {
1113 			dev_desc->sig_type = SIG_TYPE_GUID;
1114 			memcpy(&dev_desc->guid_sig, &pgpt_head->disk_guid,
1115 			      sizeof(empty));
1116 		} else if (mbr->unique_mbr_signature != 0) {
1117 			dev_desc->sig_type = SIG_TYPE_MBR;
1118 			dev_desc->mbr_sig = mbr->unique_mbr_signature;
1119 		}
1120 	}
1121 
1122 	/* Read and allocate Partition Table Entries */
1123 	*pgpt_pte = alloc_read_gpt_entries(dev_desc, pgpt_head);
1124 	if (*pgpt_pte == NULL) {
1125 		printf("GPT: Failed to allocate memory for PTE\n");
1126 		return 0;
1127 	}
1128 
1129 	if (validate_gpt_entries(pgpt_head, *pgpt_pte)) {
1130 		free(*pgpt_pte);
1131 		*pgpt_pte = NULL;
1132 		return 0;
1133 	}
1134 
1135 	/* We're done, all's well */
1136 	return 1;
1137 }
1138 
1139 /**
1140  * alloc_read_gpt_entries(): reads partition entries from disk
1141  * @dev_desc
1142  * @gpt - GPT header
1143  *
1144  * Description: Returns ptes on success,  NULL on error.
1145  * Allocates space for PTEs based on information found in @gpt.
1146  * Notes: remember to free pte when you're done!
1147  */
1148 static gpt_entry *alloc_read_gpt_entries(struct blk_desc *dev_desc,
1149 					 gpt_header *pgpt_head)
1150 {
1151 	size_t count = 0, blk_cnt;
1152 	lbaint_t blk;
1153 	gpt_entry *pte = NULL;
1154 
1155 	if (!dev_desc || !pgpt_head) {
1156 		printf("%s: Invalid Argument(s)\n", __func__);
1157 		return NULL;
1158 	}
1159 
1160 	count = le32_to_cpu(pgpt_head->num_partition_entries) *
1161 		le32_to_cpu(pgpt_head->sizeof_partition_entry);
1162 
1163 	debug("%s: count = %u * %u = %lu\n", __func__,
1164 	      (u32) le32_to_cpu(pgpt_head->num_partition_entries),
1165 	      (u32) le32_to_cpu(pgpt_head->sizeof_partition_entry),
1166 	      (ulong)count);
1167 
1168 	/* Allocate memory for PTE, remember to FREE */
1169 	if (count != 0) {
1170 		pte = memalign(ARCH_DMA_MINALIGN,
1171 			       PAD_TO_BLOCKSIZE(count, dev_desc));
1172 	}
1173 
1174 	if (count == 0 || pte == NULL) {
1175 		printf("%s: ERROR: Can't allocate %#lX bytes for GPT Entries\n",
1176 		       __func__, (ulong)count);
1177 		return NULL;
1178 	}
1179 
1180 	/* Read GPT Entries from device */
1181 	blk = le64_to_cpu(pgpt_head->partition_entry_lba);
1182 	blk_cnt = BLOCK_CNT(count, dev_desc);
1183 	if (blk_dread(dev_desc, blk, (lbaint_t)blk_cnt, pte) != blk_cnt) {
1184 		printf("*** ERROR: Can't read GPT Entries ***\n");
1185 		free(pte);
1186 		return NULL;
1187 	}
1188 	return pte;
1189 }
1190 
1191 /**
1192  * is_pte_valid(): validates a single Partition Table Entry
1193  * @gpt_entry - Pointer to a single Partition Table Entry
1194  *
1195  * Description: returns 1 if valid,  0 on error.
1196  */
1197 static int is_pte_valid(gpt_entry * pte)
1198 {
1199 	efi_guid_t unused_guid;
1200 
1201 	if (!pte) {
1202 		printf("%s: Invalid Argument(s)\n", __func__);
1203 		return 0;
1204 	}
1205 
1206 	/* Only one validation for now:
1207 	 * The GUID Partition Type != Unused Entry (ALL-ZERO)
1208 	 */
1209 	memset(unused_guid.b, 0, sizeof(unused_guid.b));
1210 
1211 	if (memcmp(pte->partition_type_guid.b, unused_guid.b,
1212 		sizeof(unused_guid.b)) == 0) {
1213 
1214 		debug("%s: Found an unused PTE GUID at 0x%08X\n", __func__,
1215 		      (unsigned int)(uintptr_t)pte);
1216 
1217 		return 0;
1218 	} else {
1219 		return 1;
1220 	}
1221 }
1222 
1223 /*
1224  * Add an 'a_' prefix so it comes before 'dos' in the linker list. We need to
1225  * check EFI first, since a DOS partition is often used as a 'protective MBR'
1226  * with EFI.
1227  */
1228 U_BOOT_PART_TYPE(a_efi) = {
1229 	.name		= "EFI",
1230 	.part_type	= PART_TYPE_EFI,
1231 	.max_entries	= GPT_ENTRY_NUMBERS,
1232 	.get_info	= part_get_info_ptr(part_get_info_efi),
1233 	.print		= part_print_ptr(part_print_efi),
1234 	.test		= part_test_efi,
1235 };
1236 #endif
1237