xref: /openbmc/u-boot/disk/part_efi.c (revision 9d466f2f)
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 CONFIG_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 	ALLOC_CACHE_ALIGN_BUFFER_PAD(gpt_header, gpt_head, 1, dev_desc->blksz);
273 	gpt_entry *gpt_pte = NULL;
274 
275 	/* "part" argument must be at least 1 */
276 	if (part < 1) {
277 		printf("%s: Invalid Argument(s)\n", __func__);
278 		return -1;
279 	}
280 
281 	/* This function validates AND fills in the GPT header and PTE */
282 	if (is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA,
283 			gpt_head, &gpt_pte) != 1) {
284 		printf("%s: *** ERROR: Invalid GPT ***\n", __func__);
285 		if (is_gpt_valid(dev_desc, (dev_desc->lba - 1),
286 				 gpt_head, &gpt_pte) != 1) {
287 			printf("%s: *** ERROR: Invalid Backup GPT ***\n",
288 			       __func__);
289 			return -1;
290 		} else {
291 			printf("%s: ***        Using Backup GPT ***\n",
292 			       __func__);
293 		}
294 	}
295 
296 	if (part > le32_to_cpu(gpt_head->num_partition_entries) ||
297 	    !is_pte_valid(&gpt_pte[part - 1])) {
298 		debug("%s: *** ERROR: Invalid partition number %d ***\n",
299 			__func__, part);
300 		free(gpt_pte);
301 		return -1;
302 	}
303 
304 	/* The 'lbaint_t' casting may limit the maximum disk size to 2 TB */
305 	info->start = (lbaint_t)le64_to_cpu(gpt_pte[part - 1].starting_lba);
306 	/* The ending LBA is inclusive, to calculate size, add 1 to it */
307 	info->size = (lbaint_t)le64_to_cpu(gpt_pte[part - 1].ending_lba) + 1
308 		     - info->start;
309 	info->blksz = dev_desc->blksz;
310 
311 	sprintf((char *)info->name, "%s",
312 			print_efiname(&gpt_pte[part - 1]));
313 	strcpy((char *)info->type, "U-Boot");
314 	info->bootable = is_bootable(&gpt_pte[part - 1]);
315 #if CONFIG_IS_ENABLED(PARTITION_UUIDS)
316 	uuid_bin_to_str(gpt_pte[part - 1].unique_partition_guid.b, info->uuid,
317 			UUID_STR_FORMAT_GUID);
318 #endif
319 #ifdef CONFIG_PARTITION_TYPE_GUID
320 	uuid_bin_to_str(gpt_pte[part - 1].partition_type_guid.b,
321 			info->type_guid, UUID_STR_FORMAT_GUID);
322 #endif
323 
324 	debug("%s: start 0x" LBAF ", size 0x" LBAF ", name %s\n", __func__,
325 	      info->start, info->size, info->name);
326 
327 	/* Remember to free pte */
328 	free(gpt_pte);
329 	return 0;
330 }
331 
332 static int part_test_efi(struct blk_desc *dev_desc)
333 {
334 	ALLOC_CACHE_ALIGN_BUFFER_PAD(legacy_mbr, legacymbr, 1, dev_desc->blksz);
335 
336 	/* Read legacy MBR from block 0 and validate it */
337 	if ((blk_dread(dev_desc, 0, 1, (ulong *)legacymbr) != 1)
338 		|| (is_pmbr_valid(legacymbr) != 1)) {
339 		return -1;
340 	}
341 	return 0;
342 }
343 
344 /**
345  * set_protective_mbr(): Set the EFI protective MBR
346  * @param dev_desc - block device descriptor
347  *
348  * @return - zero on success, otherwise error
349  */
350 static int set_protective_mbr(struct blk_desc *dev_desc)
351 {
352 	/* Setup the Protective MBR */
353 	ALLOC_CACHE_ALIGN_BUFFER_PAD(legacy_mbr, p_mbr, 1, dev_desc->blksz);
354 	memset(p_mbr, 0, sizeof(*p_mbr));
355 
356 	if (p_mbr == NULL) {
357 		printf("%s: calloc failed!\n", __func__);
358 		return -1;
359 	}
360 
361 	/* Read MBR to backup boot code if it exists */
362 	if (blk_dread(dev_desc, 0, 1, p_mbr) != 1) {
363 		pr_err("** Can't read from device %d **\n", dev_desc->devnum);
364 		return -1;
365 	}
366 
367 	/* Append signature */
368 	p_mbr->signature = MSDOS_MBR_SIGNATURE;
369 	p_mbr->partition_record[0].sys_ind = EFI_PMBR_OSTYPE_EFI_GPT;
370 	p_mbr->partition_record[0].start_sect = 1;
371 	p_mbr->partition_record[0].nr_sects = (u32) dev_desc->lba - 1;
372 
373 	/* Write MBR sector to the MMC device */
374 	if (blk_dwrite(dev_desc, 0, 1, p_mbr) != 1) {
375 		printf("** Can't write to device %d **\n",
376 			dev_desc->devnum);
377 		return -1;
378 	}
379 
380 	return 0;
381 }
382 
383 int write_gpt_table(struct blk_desc *dev_desc,
384 		gpt_header *gpt_h, gpt_entry *gpt_e)
385 {
386 	const int pte_blk_cnt = BLOCK_CNT((gpt_h->num_partition_entries
387 					   * sizeof(gpt_entry)), dev_desc);
388 	u32 calc_crc32;
389 
390 	debug("max lba: %x\n", (u32) dev_desc->lba);
391 	/* Setup the Protective MBR */
392 	if (set_protective_mbr(dev_desc) < 0)
393 		goto err;
394 
395 	/* Generate CRC for the Primary GPT Header */
396 	calc_crc32 = efi_crc32((const unsigned char *)gpt_e,
397 			      le32_to_cpu(gpt_h->num_partition_entries) *
398 			      le32_to_cpu(gpt_h->sizeof_partition_entry));
399 	gpt_h->partition_entry_array_crc32 = cpu_to_le32(calc_crc32);
400 
401 	calc_crc32 = efi_crc32((const unsigned char *)gpt_h,
402 			      le32_to_cpu(gpt_h->header_size));
403 	gpt_h->header_crc32 = cpu_to_le32(calc_crc32);
404 
405 	/* Write the First GPT to the block right after the Legacy MBR */
406 	if (blk_dwrite(dev_desc, 1, 1, gpt_h) != 1)
407 		goto err;
408 
409 	if (blk_dwrite(dev_desc, le64_to_cpu(gpt_h->partition_entry_lba),
410 		       pte_blk_cnt, gpt_e) != pte_blk_cnt)
411 		goto err;
412 
413 	prepare_backup_gpt_header(gpt_h);
414 
415 	if (blk_dwrite(dev_desc, (lbaint_t)le64_to_cpu(gpt_h->last_usable_lba)
416 		       + 1, pte_blk_cnt, gpt_e) != pte_blk_cnt)
417 		goto err;
418 
419 	if (blk_dwrite(dev_desc, (lbaint_t)le64_to_cpu(gpt_h->my_lba), 1,
420 		       gpt_h) != 1)
421 		goto err;
422 
423 	debug("GPT successfully written to block device!\n");
424 	return 0;
425 
426  err:
427 	printf("** Can't write to device %d **\n", dev_desc->devnum);
428 	return -1;
429 }
430 
431 int gpt_fill_pte(struct blk_desc *dev_desc,
432 		 gpt_header *gpt_h, gpt_entry *gpt_e,
433 		 disk_partition_t *partitions, int parts)
434 {
435 	lbaint_t offset = (lbaint_t)le64_to_cpu(gpt_h->first_usable_lba);
436 	lbaint_t last_usable_lba = (lbaint_t)
437 			le64_to_cpu(gpt_h->last_usable_lba);
438 	int i, k;
439 	size_t efiname_len, dosname_len;
440 #if CONFIG_IS_ENABLED(PARTITION_UUIDS)
441 	char *str_uuid;
442 	unsigned char *bin_uuid;
443 #endif
444 #ifdef CONFIG_PARTITION_TYPE_GUID
445 	char *str_type_guid;
446 	unsigned char *bin_type_guid;
447 #endif
448 	size_t hdr_start = gpt_h->my_lba;
449 	size_t hdr_end = hdr_start + 1;
450 
451 	size_t pte_start = gpt_h->partition_entry_lba;
452 	size_t pte_end = pte_start +
453 		gpt_h->num_partition_entries * gpt_h->sizeof_partition_entry /
454 		dev_desc->blksz;
455 
456 	for (i = 0; i < parts; i++) {
457 		/* partition starting lba */
458 		lbaint_t start = partitions[i].start;
459 		lbaint_t size = partitions[i].size;
460 
461 		if (start) {
462 			offset = start + size;
463 		} else {
464 			start = offset;
465 			offset += size;
466 		}
467 
468 		/*
469 		 * If our partition overlaps with either the GPT
470 		 * header, or the partition entry, reject it.
471 		 */
472 		if (((start < hdr_end && hdr_start < (start + size)) ||
473 		     (start < pte_end && pte_start < (start + size)))) {
474 			printf("Partition overlap\n");
475 			return -1;
476 		}
477 
478 		gpt_e[i].starting_lba = cpu_to_le64(start);
479 
480 		if (offset > (last_usable_lba + 1)) {
481 			printf("Partitions layout exceds disk size\n");
482 			return -1;
483 		}
484 		/* partition ending lba */
485 		if ((i == parts - 1) && (size == 0))
486 			/* extend the last partition to maximuim */
487 			gpt_e[i].ending_lba = gpt_h->last_usable_lba;
488 		else
489 			gpt_e[i].ending_lba = cpu_to_le64(offset - 1);
490 
491 #ifdef CONFIG_PARTITION_TYPE_GUID
492 		str_type_guid = partitions[i].type_guid;
493 		bin_type_guid = gpt_e[i].partition_type_guid.b;
494 		if (strlen(str_type_guid)) {
495 			if (uuid_str_to_bin(str_type_guid, bin_type_guid,
496 					    UUID_STR_FORMAT_GUID)) {
497 				printf("Partition no. %d: invalid type guid: %s\n",
498 				       i, str_type_guid);
499 				return -1;
500 			}
501 		} else {
502 			/* default partition type GUID */
503 			memcpy(bin_type_guid,
504 			       &PARTITION_BASIC_DATA_GUID, 16);
505 		}
506 #else
507 		/* partition type GUID */
508 		memcpy(gpt_e[i].partition_type_guid.b,
509 			&PARTITION_BASIC_DATA_GUID, 16);
510 #endif
511 
512 #if CONFIG_IS_ENABLED(PARTITION_UUIDS)
513 		str_uuid = partitions[i].uuid;
514 		bin_uuid = gpt_e[i].unique_partition_guid.b;
515 
516 		if (uuid_str_to_bin(str_uuid, bin_uuid, UUID_STR_FORMAT_GUID)) {
517 			printf("Partition no. %d: invalid guid: %s\n",
518 				i, str_uuid);
519 			return -1;
520 		}
521 #endif
522 
523 		/* partition attributes */
524 		memset(&gpt_e[i].attributes, 0,
525 		       sizeof(gpt_entry_attributes));
526 
527 		if (partitions[i].bootable)
528 			gpt_e[i].attributes.fields.legacy_bios_bootable = 1;
529 
530 		/* partition name */
531 		efiname_len = sizeof(gpt_e[i].partition_name)
532 			/ sizeof(efi_char16_t);
533 		dosname_len = sizeof(partitions[i].name);
534 
535 		memset(gpt_e[i].partition_name, 0,
536 		       sizeof(gpt_e[i].partition_name));
537 
538 		for (k = 0; k < min(dosname_len, efiname_len); k++)
539 			gpt_e[i].partition_name[k] =
540 				(efi_char16_t)(partitions[i].name[k]);
541 
542 		debug("%s: name: %s offset[%d]: 0x" LBAF
543 		      " size[%d]: 0x" LBAF "\n",
544 		      __func__, partitions[i].name, i,
545 		      offset, i, size);
546 	}
547 
548 	return 0;
549 }
550 
551 static uint32_t partition_entries_offset(struct blk_desc *dev_desc)
552 {
553 	uint32_t offset_blks = 2;
554 	uint32_t __maybe_unused offset_bytes;
555 	int __maybe_unused config_offset;
556 
557 #if defined(CONFIG_EFI_PARTITION_ENTRIES_OFF)
558 	/*
559 	 * Some architectures require their SPL loader at a fixed
560 	 * address within the first 16KB of the disk.  To avoid an
561 	 * overlap with the partition entries of the EFI partition
562 	 * table, the first safe offset (in bytes, from the start of
563 	 * the disk) for the entries can be set in
564 	 * CONFIG_EFI_PARTITION_ENTRIES_OFF.
565 	 */
566 	offset_bytes =
567 		PAD_TO_BLOCKSIZE(CONFIG_EFI_PARTITION_ENTRIES_OFF, dev_desc);
568 	offset_blks = offset_bytes / dev_desc->blksz;
569 #endif
570 
571 #if defined(CONFIG_OF_CONTROL)
572 	/*
573 	 * Allow the offset of the first partition entires (in bytes
574 	 * from the start of the device) to be specified as a property
575 	 * of the device tree '/config' node.
576 	 */
577 	config_offset = fdtdec_get_config_int(gd->fdt_blob,
578 					      "u-boot,efi-partition-entries-offset",
579 					      -EINVAL);
580 	if (config_offset != -EINVAL) {
581 		offset_bytes = PAD_TO_BLOCKSIZE(config_offset, dev_desc);
582 		offset_blks = offset_bytes / dev_desc->blksz;
583 	}
584 #endif
585 
586 	debug("efi: partition entries offset (in blocks): %d\n", offset_blks);
587 
588 	/*
589 	 * The earliest LBA this can be at is LBA#2 (i.e. right behind
590 	 * the (protective) MBR and the GPT header.
591 	 */
592 	if (offset_blks < 2)
593 		offset_blks = 2;
594 
595 	return offset_blks;
596 }
597 
598 int gpt_fill_header(struct blk_desc *dev_desc, gpt_header *gpt_h,
599 		char *str_guid, int parts_count)
600 {
601 	gpt_h->signature = cpu_to_le64(GPT_HEADER_SIGNATURE);
602 	gpt_h->revision = cpu_to_le32(GPT_HEADER_REVISION_V1);
603 	gpt_h->header_size = cpu_to_le32(sizeof(gpt_header));
604 	gpt_h->my_lba = cpu_to_le64(1);
605 	gpt_h->alternate_lba = cpu_to_le64(dev_desc->lba - 1);
606 	gpt_h->last_usable_lba = cpu_to_le64(dev_desc->lba - 34);
607 	gpt_h->partition_entry_lba =
608 		cpu_to_le64(partition_entries_offset(dev_desc));
609 	gpt_h->first_usable_lba =
610 		cpu_to_le64(le64_to_cpu(gpt_h->partition_entry_lba) + 32);
611 	gpt_h->num_partition_entries = cpu_to_le32(GPT_ENTRY_NUMBERS);
612 	gpt_h->sizeof_partition_entry = cpu_to_le32(sizeof(gpt_entry));
613 	gpt_h->header_crc32 = 0;
614 	gpt_h->partition_entry_array_crc32 = 0;
615 
616 	if (uuid_str_to_bin(str_guid, gpt_h->disk_guid.b, UUID_STR_FORMAT_GUID))
617 		return -1;
618 
619 	return 0;
620 }
621 
622 int gpt_restore(struct blk_desc *dev_desc, char *str_disk_guid,
623 		disk_partition_t *partitions, int parts_count)
624 {
625 	gpt_header *gpt_h;
626 	gpt_entry *gpt_e;
627 	int ret, size;
628 
629 	size = PAD_TO_BLOCKSIZE(sizeof(gpt_header), dev_desc);
630 	gpt_h = malloc_cache_aligned(size);
631 	if (gpt_h == NULL) {
632 		printf("%s: calloc failed!\n", __func__);
633 		return -1;
634 	}
635 	memset(gpt_h, 0, size);
636 
637 	size = PAD_TO_BLOCKSIZE(GPT_ENTRY_NUMBERS * sizeof(gpt_entry),
638 				dev_desc);
639 	gpt_e = malloc_cache_aligned(size);
640 	if (gpt_e == NULL) {
641 		printf("%s: calloc failed!\n", __func__);
642 		free(gpt_h);
643 		return -1;
644 	}
645 	memset(gpt_e, 0, size);
646 
647 	/* Generate Primary GPT header (LBA1) */
648 	ret = gpt_fill_header(dev_desc, gpt_h, str_disk_guid, parts_count);
649 	if (ret)
650 		goto err;
651 
652 	/* Generate partition entries */
653 	ret = gpt_fill_pte(dev_desc, gpt_h, gpt_e, partitions, parts_count);
654 	if (ret)
655 		goto err;
656 
657 	/* Write GPT partition table */
658 	ret = write_gpt_table(dev_desc, gpt_h, gpt_e);
659 
660 err:
661 	free(gpt_e);
662 	free(gpt_h);
663 	return ret;
664 }
665 
666 static void gpt_convert_efi_name_to_char(char *s, efi_char16_t *es, int n)
667 {
668 	char *ess = (char *)es;
669 	int i, j;
670 
671 	memset(s, '\0', n);
672 
673 	for (i = 0, j = 0; j < n; i += 2, j++) {
674 		s[j] = ess[i];
675 		if (!ess[i])
676 			return;
677 	}
678 }
679 
680 int gpt_verify_headers(struct blk_desc *dev_desc, gpt_header *gpt_head,
681 		       gpt_entry **gpt_pte)
682 {
683 	/*
684 	 * This function validates AND
685 	 * fills in the GPT header and PTE
686 	 */
687 	if (is_gpt_valid(dev_desc,
688 			 GPT_PRIMARY_PARTITION_TABLE_LBA,
689 			 gpt_head, gpt_pte) != 1) {
690 		printf("%s: *** ERROR: Invalid GPT ***\n",
691 		       __func__);
692 		return -1;
693 	}
694 	if (is_gpt_valid(dev_desc, (dev_desc->lba - 1),
695 			 gpt_head, gpt_pte) != 1) {
696 		printf("%s: *** ERROR: Invalid Backup GPT ***\n",
697 		       __func__);
698 		return -1;
699 	}
700 
701 	return 0;
702 }
703 
704 int gpt_verify_partitions(struct blk_desc *dev_desc,
705 			  disk_partition_t *partitions, int parts,
706 			  gpt_header *gpt_head, gpt_entry **gpt_pte)
707 {
708 	char efi_str[PARTNAME_SZ + 1];
709 	u64 gpt_part_size;
710 	gpt_entry *gpt_e;
711 	int ret, i;
712 
713 	ret = gpt_verify_headers(dev_desc, gpt_head, gpt_pte);
714 	if (ret)
715 		return ret;
716 
717 	gpt_e = *gpt_pte;
718 
719 	for (i = 0; i < parts; i++) {
720 		if (i == gpt_head->num_partition_entries) {
721 			pr_err("More partitions than allowed!\n");
722 			return -1;
723 		}
724 
725 		/* Check if GPT and ENV partition names match */
726 		gpt_convert_efi_name_to_char(efi_str, gpt_e[i].partition_name,
727 					     PARTNAME_SZ + 1);
728 
729 		debug("%s: part: %2d name - GPT: %16s, ENV: %16s ",
730 		      __func__, i, efi_str, partitions[i].name);
731 
732 		if (strncmp(efi_str, (char *)partitions[i].name,
733 			    sizeof(partitions->name))) {
734 			pr_err("Partition name: %s does not match %s!\n",
735 			      efi_str, (char *)partitions[i].name);
736 			return -1;
737 		}
738 
739 		/* Check if GPT and ENV sizes match */
740 		gpt_part_size = le64_to_cpu(gpt_e[i].ending_lba) -
741 			le64_to_cpu(gpt_e[i].starting_lba) + 1;
742 		debug("size(LBA) - GPT: %8llu, ENV: %8llu ",
743 		      (unsigned long long)gpt_part_size,
744 		      (unsigned long long)partitions[i].size);
745 
746 		if (le64_to_cpu(gpt_part_size) != partitions[i].size) {
747 			/* We do not check the extend partition size */
748 			if ((i == parts - 1) && (partitions[i].size == 0))
749 				continue;
750 
751 			pr_err("Partition %s size: %llu does not match %llu!\n",
752 			      efi_str, (unsigned long long)gpt_part_size,
753 			      (unsigned long long)partitions[i].size);
754 			return -1;
755 		}
756 
757 		/*
758 		 * Start address is optional - check only if provided
759 		 * in '$partition' variable
760 		 */
761 		if (!partitions[i].start) {
762 			debug("\n");
763 			continue;
764 		}
765 
766 		/* Check if GPT and ENV start LBAs match */
767 		debug("start LBA - GPT: %8llu, ENV: %8llu\n",
768 		      le64_to_cpu(gpt_e[i].starting_lba),
769 		      (unsigned long long)partitions[i].start);
770 
771 		if (le64_to_cpu(gpt_e[i].starting_lba) != partitions[i].start) {
772 			pr_err("Partition %s start: %llu does not match %llu!\n",
773 			      efi_str, le64_to_cpu(gpt_e[i].starting_lba),
774 			      (unsigned long long)partitions[i].start);
775 			return -1;
776 		}
777 	}
778 
779 	return 0;
780 }
781 
782 int is_valid_gpt_buf(struct blk_desc *dev_desc, void *buf)
783 {
784 	gpt_header *gpt_h;
785 	gpt_entry *gpt_e;
786 
787 	/* determine start of GPT Header in the buffer */
788 	gpt_h = buf + (GPT_PRIMARY_PARTITION_TABLE_LBA *
789 		       dev_desc->blksz);
790 	if (validate_gpt_header(gpt_h, GPT_PRIMARY_PARTITION_TABLE_LBA,
791 				dev_desc->lba))
792 		return -1;
793 
794 	/* determine start of GPT Entries in the buffer */
795 	gpt_e = buf + (le64_to_cpu(gpt_h->partition_entry_lba) *
796 		       dev_desc->blksz);
797 	if (validate_gpt_entries(gpt_h, gpt_e))
798 		return -1;
799 
800 	return 0;
801 }
802 
803 int write_mbr_and_gpt_partitions(struct blk_desc *dev_desc, void *buf)
804 {
805 	gpt_header *gpt_h;
806 	gpt_entry *gpt_e;
807 	int gpt_e_blk_cnt;
808 	lbaint_t lba;
809 	int cnt;
810 
811 	if (is_valid_gpt_buf(dev_desc, buf))
812 		return -1;
813 
814 	/* determine start of GPT Header in the buffer */
815 	gpt_h = buf + (GPT_PRIMARY_PARTITION_TABLE_LBA *
816 		       dev_desc->blksz);
817 
818 	/* determine start of GPT Entries in the buffer */
819 	gpt_e = buf + (le64_to_cpu(gpt_h->partition_entry_lba) *
820 		       dev_desc->blksz);
821 	gpt_e_blk_cnt = BLOCK_CNT((le32_to_cpu(gpt_h->num_partition_entries) *
822 				   le32_to_cpu(gpt_h->sizeof_partition_entry)),
823 				  dev_desc);
824 
825 	/* write MBR */
826 	lba = 0;	/* MBR is always at 0 */
827 	cnt = 1;	/* MBR (1 block) */
828 	if (blk_dwrite(dev_desc, lba, cnt, buf) != cnt) {
829 		printf("%s: failed writing '%s' (%d blks at 0x" LBAF ")\n",
830 		       __func__, "MBR", cnt, lba);
831 		return 1;
832 	}
833 
834 	/* write Primary GPT */
835 	lba = GPT_PRIMARY_PARTITION_TABLE_LBA;
836 	cnt = 1;	/* GPT Header (1 block) */
837 	if (blk_dwrite(dev_desc, lba, cnt, gpt_h) != cnt) {
838 		printf("%s: failed writing '%s' (%d blks at 0x" LBAF ")\n",
839 		       __func__, "Primary GPT Header", cnt, lba);
840 		return 1;
841 	}
842 
843 	lba = le64_to_cpu(gpt_h->partition_entry_lba);
844 	cnt = gpt_e_blk_cnt;
845 	if (blk_dwrite(dev_desc, lba, cnt, gpt_e) != cnt) {
846 		printf("%s: failed writing '%s' (%d blks at 0x" LBAF ")\n",
847 		       __func__, "Primary GPT Entries", cnt, lba);
848 		return 1;
849 	}
850 
851 	prepare_backup_gpt_header(gpt_h);
852 
853 	/* write Backup GPT */
854 	lba = le64_to_cpu(gpt_h->partition_entry_lba);
855 	cnt = gpt_e_blk_cnt;
856 	if (blk_dwrite(dev_desc, lba, cnt, gpt_e) != cnt) {
857 		printf("%s: failed writing '%s' (%d blks at 0x" LBAF ")\n",
858 		       __func__, "Backup GPT Entries", cnt, lba);
859 		return 1;
860 	}
861 
862 	lba = le64_to_cpu(gpt_h->my_lba);
863 	cnt = 1;	/* GPT Header (1 block) */
864 	if (blk_dwrite(dev_desc, lba, cnt, gpt_h) != cnt) {
865 		printf("%s: failed writing '%s' (%d blks at 0x" LBAF ")\n",
866 		       __func__, "Backup GPT Header", cnt, lba);
867 		return 1;
868 	}
869 
870 	return 0;
871 }
872 #endif
873 
874 /*
875  * Private functions
876  */
877 /*
878  * pmbr_part_valid(): Check for EFI partition signature
879  *
880  * Returns: 1 if EFI GPT partition type is found.
881  */
882 static int pmbr_part_valid(struct partition *part)
883 {
884 	if (part->sys_ind == EFI_PMBR_OSTYPE_EFI_GPT &&
885 		get_unaligned_le32(&part->start_sect) == 1UL) {
886 		return 1;
887 	}
888 
889 	return 0;
890 }
891 
892 /*
893  * is_pmbr_valid(): test Protective MBR for validity
894  *
895  * Returns: 1 if PMBR is valid, 0 otherwise.
896  * Validity depends on two things:
897  *  1) MSDOS signature is in the last two bytes of the MBR
898  *  2) One partition of type 0xEE is found, checked by pmbr_part_valid()
899  */
900 static int is_pmbr_valid(legacy_mbr * mbr)
901 {
902 	int i = 0;
903 
904 	if (!mbr || le16_to_cpu(mbr->signature) != MSDOS_MBR_SIGNATURE)
905 		return 0;
906 
907 	for (i = 0; i < 4; i++) {
908 		if (pmbr_part_valid(&mbr->partition_record[i])) {
909 			return 1;
910 		}
911 	}
912 	return 0;
913 }
914 
915 /**
916  * is_gpt_valid() - tests one GPT header and PTEs for validity
917  *
918  * lba is the logical block address of the GPT header to test
919  * gpt is a GPT header ptr, filled on return.
920  * ptes is a PTEs ptr, filled on return.
921  *
922  * Description: returns 1 if valid,  0 on error.
923  * If valid, returns pointers to PTEs.
924  */
925 static int is_gpt_valid(struct blk_desc *dev_desc, u64 lba,
926 			gpt_header *pgpt_head, gpt_entry **pgpt_pte)
927 {
928 	/* Confirm valid arguments prior to allocation. */
929 	if (!dev_desc || !pgpt_head) {
930 		printf("%s: Invalid Argument(s)\n", __func__);
931 		return 0;
932 	}
933 
934 	ALLOC_CACHE_ALIGN_BUFFER_PAD(legacy_mbr, mbr, 1, dev_desc->blksz);
935 
936 	/* Read MBR Header from device */
937 	if (blk_dread(dev_desc, 0, 1, (ulong *)mbr) != 1) {
938 		printf("*** ERROR: Can't read MBR header ***\n");
939 		return 0;
940 	}
941 
942 	/* Read GPT Header from device */
943 	if (blk_dread(dev_desc, (lbaint_t)lba, 1, pgpt_head) != 1) {
944 		printf("*** ERROR: Can't read GPT header ***\n");
945 		return 0;
946 	}
947 
948 	if (validate_gpt_header(pgpt_head, (lbaint_t)lba, dev_desc->lba))
949 		return 0;
950 
951 	if (dev_desc->sig_type == SIG_TYPE_NONE) {
952 		efi_guid_t empty = {};
953 		if (memcmp(&pgpt_head->disk_guid, &empty, sizeof(empty))) {
954 			dev_desc->sig_type = SIG_TYPE_GUID;
955 			memcpy(&dev_desc->guid_sig, &pgpt_head->disk_guid,
956 			      sizeof(empty));
957 		} else if (mbr->unique_mbr_signature != 0) {
958 			dev_desc->sig_type = SIG_TYPE_MBR;
959 			dev_desc->mbr_sig = mbr->unique_mbr_signature;
960 		}
961 	}
962 
963 	/* Read and allocate Partition Table Entries */
964 	*pgpt_pte = alloc_read_gpt_entries(dev_desc, pgpt_head);
965 	if (*pgpt_pte == NULL) {
966 		printf("GPT: Failed to allocate memory for PTE\n");
967 		return 0;
968 	}
969 
970 	if (validate_gpt_entries(pgpt_head, *pgpt_pte)) {
971 		free(*pgpt_pte);
972 		return 0;
973 	}
974 
975 	/* We're done, all's well */
976 	return 1;
977 }
978 
979 /**
980  * alloc_read_gpt_entries(): reads partition entries from disk
981  * @dev_desc
982  * @gpt - GPT header
983  *
984  * Description: Returns ptes on success,  NULL on error.
985  * Allocates space for PTEs based on information found in @gpt.
986  * Notes: remember to free pte when you're done!
987  */
988 static gpt_entry *alloc_read_gpt_entries(struct blk_desc *dev_desc,
989 					 gpt_header *pgpt_head)
990 {
991 	size_t count = 0, blk_cnt;
992 	lbaint_t blk;
993 	gpt_entry *pte = NULL;
994 
995 	if (!dev_desc || !pgpt_head) {
996 		printf("%s: Invalid Argument(s)\n", __func__);
997 		return NULL;
998 	}
999 
1000 	count = le32_to_cpu(pgpt_head->num_partition_entries) *
1001 		le32_to_cpu(pgpt_head->sizeof_partition_entry);
1002 
1003 	debug("%s: count = %u * %u = %lu\n", __func__,
1004 	      (u32) le32_to_cpu(pgpt_head->num_partition_entries),
1005 	      (u32) le32_to_cpu(pgpt_head->sizeof_partition_entry),
1006 	      (ulong)count);
1007 
1008 	/* Allocate memory for PTE, remember to FREE */
1009 	if (count != 0) {
1010 		pte = memalign(ARCH_DMA_MINALIGN,
1011 			       PAD_TO_BLOCKSIZE(count, dev_desc));
1012 	}
1013 
1014 	if (count == 0 || pte == NULL) {
1015 		printf("%s: ERROR: Can't allocate %#lX bytes for GPT Entries\n",
1016 		       __func__, (ulong)count);
1017 		return NULL;
1018 	}
1019 
1020 	/* Read GPT Entries from device */
1021 	blk = le64_to_cpu(pgpt_head->partition_entry_lba);
1022 	blk_cnt = BLOCK_CNT(count, dev_desc);
1023 	if (blk_dread(dev_desc, blk, (lbaint_t)blk_cnt, pte) != blk_cnt) {
1024 		printf("*** ERROR: Can't read GPT Entries ***\n");
1025 		free(pte);
1026 		return NULL;
1027 	}
1028 	return pte;
1029 }
1030 
1031 /**
1032  * is_pte_valid(): validates a single Partition Table Entry
1033  * @gpt_entry - Pointer to a single Partition Table Entry
1034  *
1035  * Description: returns 1 if valid,  0 on error.
1036  */
1037 static int is_pte_valid(gpt_entry * pte)
1038 {
1039 	efi_guid_t unused_guid;
1040 
1041 	if (!pte) {
1042 		printf("%s: Invalid Argument(s)\n", __func__);
1043 		return 0;
1044 	}
1045 
1046 	/* Only one validation for now:
1047 	 * The GUID Partition Type != Unused Entry (ALL-ZERO)
1048 	 */
1049 	memset(unused_guid.b, 0, sizeof(unused_guid.b));
1050 
1051 	if (memcmp(pte->partition_type_guid.b, unused_guid.b,
1052 		sizeof(unused_guid.b)) == 0) {
1053 
1054 		debug("%s: Found an unused PTE GUID at 0x%08X\n", __func__,
1055 		      (unsigned int)(uintptr_t)pte);
1056 
1057 		return 0;
1058 	} else {
1059 		return 1;
1060 	}
1061 }
1062 
1063 /*
1064  * Add an 'a_' prefix so it comes before 'dos' in the linker list. We need to
1065  * check EFI first, since a DOS partition is often used as a 'protective MBR'
1066  * with EFI.
1067  */
1068 U_BOOT_PART_TYPE(a_efi) = {
1069 	.name		= "EFI",
1070 	.part_type	= PART_TYPE_EFI,
1071 	.max_entries	= GPT_ENTRY_NUMBERS,
1072 	.get_info	= part_get_info_ptr(part_get_info_efi),
1073 	.print		= part_print_ptr(part_print_efi),
1074 	.test		= part_test_efi,
1075 };
1076 #endif
1077