xref: /openbmc/u-boot/cmd/mvebu/bubt.c (revision c7c47ca2)
1 /*
2  * Copyright (C) 2016 Marvell International Ltd.
3  *
4  * SPDX-License-Identifier:	GPL-2.0
5  * https://spdx.org/licenses
6  */
7 
8 #include <config.h>
9 #include <common.h>
10 #include <command.h>
11 #include <vsprintf.h>
12 #include <errno.h>
13 #include <dm.h>
14 
15 #include <spi_flash.h>
16 #include <spi.h>
17 #include <nand.h>
18 #include <usb.h>
19 #include <fs.h>
20 #include <mmc.h>
21 #include <u-boot/sha1.h>
22 #include <u-boot/sha256.h>
23 
24 #ifndef CONFIG_SYS_MMC_ENV_DEV
25 #define CONFIG_SYS_MMC_ENV_DEV	0
26 #endif
27 
28 #if defined(CONFIG_ARMADA_8K)
29 #define MAIN_HDR_MAGIC		0xB105B002
30 
31 struct mvebu_image_header {
32 	u32	magic;			/*  0-3  */
33 	u32	prolog_size;		/*  4-7  */
34 	u32	prolog_checksum;	/*  8-11 */
35 	u32	boot_image_size;	/* 12-15 */
36 	u32	boot_image_checksum;	/* 16-19 */
37 	u32	rsrvd0;			/* 20-23 */
38 	u32	load_addr;		/* 24-27 */
39 	u32	exec_addr;		/* 28-31 */
40 	u8	uart_cfg;		/*  32   */
41 	u8	baudrate;		/*  33   */
42 	u8	ext_count;		/*  34   */
43 	u8	aux_flags;		/*  35   */
44 	u32	io_arg_0;		/* 36-39 */
45 	u32	io_arg_1;		/* 40-43 */
46 	u32	io_arg_2;		/* 43-47 */
47 	u32	io_arg_3;		/* 48-51 */
48 	u32	rsrvd1;			/* 52-55 */
49 	u32	rsrvd2;			/* 56-59 */
50 	u32	rsrvd3;			/* 60-63 */
51 };
52 #elif defined(CONFIG_ARMADA_3700)	/* A3700 */
53 #define HASH_SUM_LEN		16
54 #define IMAGE_VERSION_3_6_0	0x030600
55 #define IMAGE_VERSION_3_5_0	0x030500
56 
57 struct common_tim_data {
58 	u32	version;
59 	u32	identifier;
60 	u32	trusted;
61 	u32	issue_date;
62 	u32	oem_unique_id;
63 	u32	reserved[5];		/* Reserve 20 bytes */
64 	u32	boot_flash_sign;
65 	u32	num_images;
66 	u32	num_keys;
67 	u32	size_of_reserved;
68 };
69 
70 struct mvebu_image_info {
71 	u32	image_id;
72 	u32	next_image_id;
73 	u32	flash_entry_addr;
74 	u32	load_addr;
75 	u32	image_size;
76 	u32	image_size_to_hash;
77 	u32	hash_algorithm_id;
78 	u32	hash[HASH_SUM_LEN];	/* Reserve 512 bits for the hash */
79 	u32	partition_number;
80 	u32	enc_algorithm_id;
81 	u32	encrypt_start_offset;
82 	u32	encrypt_size;
83 };
84 #endif /* CONFIG_ARMADA_XXX */
85 
86 struct bubt_dev {
87 	char name[8];
88 	size_t (*read)(const char *file_name);
89 	int (*write)(size_t image_size);
90 	int (*active)(void);
91 };
92 
93 static ulong get_load_addr(void)
94 {
95 	const char *addr_str;
96 	unsigned long addr;
97 
98 	addr_str = getenv("loadaddr");
99 	if (addr_str)
100 		addr = simple_strtoul(addr_str, NULL, 16);
101 	else
102 		addr = CONFIG_SYS_LOAD_ADDR;
103 
104 	return addr;
105 }
106 
107 /********************************************************************
108  *     eMMC services
109  ********************************************************************/
110 #ifdef CONFIG_DM_MMC
111 static int mmc_burn_image(size_t image_size)
112 {
113 	struct mmc	*mmc;
114 	lbaint_t	start_lba;
115 	lbaint_t	blk_count;
116 	ulong		blk_written;
117 	int		err;
118 	const u8	mmc_dev_num = CONFIG_SYS_MMC_ENV_DEV;
119 
120 	mmc = find_mmc_device(mmc_dev_num);
121 	if (!mmc) {
122 		printf("No SD/MMC/eMMC card found\n");
123 		return -ENOMEDIUM;
124 	}
125 
126 	err = mmc_init(mmc);
127 	if (err) {
128 		printf("%s(%d) init failed\n", IS_SD(mmc) ? "SD" : "MMC",
129 		       mmc_dev_num);
130 		return err;
131 	}
132 
133 #ifdef CONFIG_SYS_MMC_ENV_PART
134 	if (mmc->part_num != CONFIG_SYS_MMC_ENV_PART) {
135 		err = mmc_switch_part(mmc_dev_num, CONFIG_SYS_MMC_ENV_PART);
136 		if (err) {
137 			printf("MMC partition switch failed\n");
138 			return err;
139 		}
140 	}
141 #endif
142 
143 	/* SD reserves LBA-0 for MBR and boots from LBA-1,
144 	 * MMC/eMMC boots from LBA-0
145 	 */
146 	start_lba = IS_SD(mmc) ? 1 : 0;
147 	blk_count = image_size / mmc->block_dev.blksz;
148 	if (image_size % mmc->block_dev.blksz)
149 		blk_count += 1;
150 
151 	blk_written = mmc->block_dev.block_write(mmc_dev_num,
152 						start_lba, blk_count,
153 						(void *)get_load_addr());
154 	if (blk_written != blk_count) {
155 		printf("Error - written %#lx blocks\n", blk_written);
156 		return -ENOSPC;
157 	}
158 	printf("Done!\n");
159 
160 #ifdef CONFIG_SYS_MMC_ENV_PART
161 	if (mmc->part_num != CONFIG_SYS_MMC_ENV_PART)
162 		mmc_switch_part(mmc_dev_num, mmc->part_num);
163 #endif
164 
165 	return 0;
166 }
167 
168 static size_t mmc_read_file(const char *file_name)
169 {
170 	loff_t		act_read = 0;
171 	int		rc;
172 	struct mmc	*mmc;
173 	const u8	mmc_dev_num = CONFIG_SYS_MMC_ENV_DEV;
174 
175 	mmc = find_mmc_device(mmc_dev_num);
176 	if (!mmc) {
177 		printf("No SD/MMC/eMMC card found\n");
178 		return 0;
179 	}
180 
181 	if (mmc_init(mmc)) {
182 		printf("%s(%d) init failed\n", IS_SD(mmc) ? "SD" : "MMC",
183 		       mmc_dev_num);
184 		return 0;
185 	}
186 
187 	/* Load from data partition (0) */
188 	if (fs_set_blk_dev("mmc", "0", FS_TYPE_ANY)) {
189 		printf("Error: MMC 0 not found\n");
190 		return 0;
191 	}
192 
193 	/* Perfrom file read */
194 	rc = fs_read(file_name, get_load_addr(), 0, 0, &act_read);
195 	if (rc)
196 		return 0;
197 
198 	return act_read;
199 }
200 
201 static int is_mmc_active(void)
202 {
203 	return 1;
204 }
205 #else /* CONFIG_DM_MMC */
206 static int mmc_burn_image(size_t image_size)
207 {
208 	return -ENODEV;
209 }
210 
211 static size_t mmc_read_file(const char *file_name)
212 {
213 	return 0;
214 }
215 
216 static int is_mmc_active(void)
217 {
218 	return 0;
219 }
220 #endif /* CONFIG_DM_MMC */
221 
222 /********************************************************************
223  *     SPI services
224  ********************************************************************/
225 #ifdef CONFIG_SPI_FLASH
226 static int spi_burn_image(size_t image_size)
227 {
228 	int ret;
229 	struct spi_flash *flash;
230 	u32 erase_bytes;
231 
232 	/* Probe the SPI bus to get the flash device */
233 	flash = spi_flash_probe(CONFIG_ENV_SPI_BUS,
234 				CONFIG_ENV_SPI_CS,
235 				CONFIG_SF_DEFAULT_SPEED,
236 				CONFIG_SF_DEFAULT_MODE);
237 	if (!flash) {
238 		printf("Failed to probe SPI Flash\n");
239 		return -ENOMEDIUM;
240 	}
241 
242 #ifdef CONFIG_SPI_FLASH_PROTECTION
243 	spi_flash_protect(flash, 0);
244 #endif
245 	erase_bytes = image_size +
246 		(flash->erase_size - image_size % flash->erase_size);
247 	printf("Erasing %d bytes (%d blocks) at offset 0 ...",
248 	       erase_bytes, erase_bytes / flash->erase_size);
249 	ret = spi_flash_erase(flash, 0, erase_bytes);
250 	if (ret)
251 		printf("Error!\n");
252 	else
253 		printf("Done!\n");
254 
255 	printf("Writing %d bytes from 0x%lx to offset 0 ...",
256 	       (int)image_size, get_load_addr());
257 	ret = spi_flash_write(flash, 0, image_size, (void *)get_load_addr());
258 	if (ret)
259 		printf("Error!\n");
260 	else
261 		printf("Done!\n");
262 
263 #ifdef CONFIG_SPI_FLASH_PROTECTION
264 	spi_flash_protect(flash, 1);
265 #endif
266 
267 	return ret;
268 }
269 
270 static int is_spi_active(void)
271 {
272 	return 1;
273 }
274 
275 #else /* CONFIG_SPI_FLASH */
276 static int spi_burn_image(size_t image_size)
277 {
278 	return -ENODEV;
279 }
280 
281 static int is_spi_active(void)
282 {
283 	return 0;
284 }
285 #endif /* CONFIG_SPI_FLASH */
286 
287 /********************************************************************
288  *     NAND services
289  ********************************************************************/
290 #ifdef CONFIG_CMD_NAND
291 static int nand_burn_image(size_t image_size)
292 {
293 	int ret, block_size;
294 	nand_info_t *nand;
295 	int dev = nand_curr_device;
296 
297 	if ((dev < 0) || (dev >= CONFIG_SYS_MAX_NAND_DEVICE) ||
298 	    (!nand_info[dev].name)) {
299 		puts("\nno devices available\n");
300 		return -ENOMEDIUM;
301 	}
302 	nand = &nand_info[dev];
303 	block_size = nand->erasesize;
304 
305 	/* Align U-Boot size to currently used blocksize */
306 	image_size = ((image_size + (block_size - 1)) & (~(block_size - 1)));
307 
308 	/* Erase the U-BOOT image space */
309 	printf("Erasing 0x%x - 0x%x:...", 0, (int)image_size);
310 	ret = nand_erase(nand, 0, image_size);
311 	if (ret) {
312 		printf("Error!\n");
313 		goto error;
314 	}
315 	printf("Done!\n");
316 
317 	/* Write the image to flash */
318 	printf("Writing image:...");
319 	printf("&image_size = 0x%p\n", (void *)&image_size);
320 	ret = nand_write(nand, 0, &image_size, (void *)get_load_addr());
321 	if (ret)
322 		printf("Error!\n");
323 	else
324 		printf("Done!\n");
325 
326 error:
327 	return ret;
328 }
329 
330 static int is_nand_active(void)
331 {
332 	return 1;
333 }
334 
335 #else /* CONFIG_CMD_NAND */
336 static int nand_burn_image(size_t image_size)
337 {
338 	return -ENODEV;
339 }
340 
341 static int is_nand_active(void)
342 {
343 	return 0;
344 }
345 #endif /* CONFIG_CMD_NAND */
346 
347 /********************************************************************
348  *     USB services
349  ********************************************************************/
350 #if defined(CONFIG_USB_STORAGE) && defined(CONFIG_BLK)
351 static size_t usb_read_file(const char *file_name)
352 {
353 	loff_t act_read = 0;
354 	struct udevice *dev;
355 	int rc;
356 
357 	usb_stop();
358 
359 	if (usb_init() < 0) {
360 		printf("Error: usb_init failed\n");
361 		return 0;
362 	}
363 
364 	/* Try to recognize storage devices immediately */
365 	blk_first_device(IF_TYPE_USB, &dev);
366 	if (!dev) {
367 		printf("Error: USB storage device not found\n");
368 		return 0;
369 	}
370 
371 	/* Always load from usb 0 */
372 	if (fs_set_blk_dev("usb", "0", FS_TYPE_ANY)) {
373 		printf("Error: USB 0 not found\n");
374 		return 0;
375 	}
376 
377 	/* Perfrom file read */
378 	rc = fs_read(file_name, get_load_addr(), 0, 0, &act_read);
379 	if (rc)
380 		return 0;
381 
382 	return act_read;
383 }
384 
385 static int is_usb_active(void)
386 {
387 	return 1;
388 }
389 
390 #else /* defined(CONFIG_USB_STORAGE) && defined (CONFIG_BLK) */
391 static size_t usb_read_file(const char *file_name)
392 {
393 	return 0;
394 }
395 
396 static int is_usb_active(void)
397 {
398 	return 0;
399 }
400 #endif /* defined(CONFIG_USB_STORAGE) && defined (CONFIG_BLK) */
401 
402 /********************************************************************
403  *     Network services
404  ********************************************************************/
405 #ifdef CONFIG_CMD_NET
406 static size_t tftp_read_file(const char *file_name)
407 {
408 	/* update global variable load_addr before tftp file from network */
409 	load_addr = get_load_addr();
410 	return net_loop(TFTPGET);
411 }
412 
413 static int is_tftp_active(void)
414 {
415 	return 1;
416 }
417 
418 #else
419 static size_t tftp_read_file(const char *file_name)
420 {
421 	return 0;
422 }
423 
424 static int is_tftp_active(void)
425 {
426 	return 0;
427 }
428 #endif /* CONFIG_CMD_NET */
429 
430 enum bubt_devices {
431 	BUBT_DEV_NET = 0,
432 	BUBT_DEV_USB,
433 	BUBT_DEV_MMC,
434 	BUBT_DEV_SPI,
435 	BUBT_DEV_NAND,
436 
437 	BUBT_MAX_DEV
438 };
439 
440 struct bubt_dev bubt_devs[BUBT_MAX_DEV] = {
441 	{"tftp", tftp_read_file, NULL, is_tftp_active},
442 	{"usb",  usb_read_file,  NULL, is_usb_active},
443 	{"mmc",  mmc_read_file,  mmc_burn_image, is_mmc_active},
444 	{"spi",  NULL, spi_burn_image,  is_spi_active},
445 	{"nand", NULL, nand_burn_image, is_nand_active},
446 };
447 
448 static int bubt_write_file(struct bubt_dev *dst, size_t image_size)
449 {
450 	if (!dst->write) {
451 		printf("Error: Write not supported on device %s\n", dst->name);
452 		return -ENOTSUPP;
453 	}
454 
455 	return dst->write(image_size);
456 }
457 
458 #if defined(CONFIG_ARMADA_8K)
459 u32 do_checksum32(u32 *start, int32_t len)
460 {
461 	u32 sum = 0;
462 	u32 *startp = start;
463 
464 	do {
465 		sum += *startp;
466 		startp++;
467 		len -= 4;
468 	} while (len > 0);
469 
470 	return sum;
471 }
472 
473 static int check_image_header(void)
474 {
475 	struct mvebu_image_header *hdr =
476 			(struct mvebu_image_header *)get_load_addr();
477 	u32 header_len = hdr->prolog_size;
478 	u32 checksum;
479 	u32 checksum_ref = hdr->prolog_checksum;
480 
481 	/*
482 	 * For now compare checksum, and magic. Later we can
483 	 * verify more stuff on the header like interface type, etc
484 	 */
485 	if (hdr->magic != MAIN_HDR_MAGIC) {
486 		printf("ERROR: Bad MAGIC 0x%08x != 0x%08x\n",
487 		       hdr->magic, MAIN_HDR_MAGIC);
488 		return -ENOEXEC;
489 	}
490 
491 	/* The checksum value is discarded from checksum calculation */
492 	hdr->prolog_checksum = 0;
493 
494 	checksum = do_checksum32((u32 *)hdr, header_len);
495 	if (checksum != checksum_ref) {
496 		printf("Error: Bad Image checksum. 0x%x != 0x%x\n",
497 		       checksum, checksum_ref);
498 		return -ENOEXEC;
499 	}
500 
501 	/* Restore the checksum before writing */
502 	hdr->prolog_checksum = checksum_ref;
503 	printf("Image checksum...OK!\n");
504 
505 	return 0;
506 }
507 #elif defined(CONFIG_ARMADA_3700) /* Armada 3700 */
508 static int check_image_header(void)
509 {
510 	struct common_tim_data *hdr = (struct common_tim_data *)get_load_addr();
511 	int image_num;
512 	u8 hash_160_output[SHA1_SUM_LEN];
513 	u8 hash_256_output[SHA256_SUM_LEN];
514 	sha1_context hash1_text;
515 	sha256_context hash256_text;
516 	u8 *hash_output;
517 	u32 hash_algorithm_id;
518 	u32 image_size_to_hash;
519 	u32 flash_entry_addr;
520 	u32 *hash_value;
521 	u32 internal_hash[HASH_SUM_LEN];
522 	const u8 *buff;
523 	u32 num_of_image = hdr->num_images;
524 	u32 version = hdr->version;
525 	u32 trusted = hdr->trusted;
526 
527 	/* bubt checksum validation only supports nontrusted images */
528 	if (trusted == 1) {
529 		printf("bypass image validation, ");
530 		printf("only untrusted image is supported now\n");
531 		return 0;
532 	}
533 	/* only supports image version 3.5 and 3.6 */
534 	if (version != IMAGE_VERSION_3_5_0 && version != IMAGE_VERSION_3_6_0) {
535 		printf("Error: Unsupported Image version = 0x%08x\n", version);
536 		return -ENOEXEC;
537 	}
538 	/* validate images hash value */
539 	for (image_num = 0; image_num < num_of_image; image_num++) {
540 		struct mvebu_image_info *info =
541 				(struct mvebu_image_info *)(get_load_addr() +
542 				sizeof(struct common_tim_data) +
543 				image_num * sizeof(struct mvebu_image_info));
544 		hash_algorithm_id = info->hash_algorithm_id;
545 		image_size_to_hash = info->image_size_to_hash;
546 		flash_entry_addr = info->flash_entry_addr;
547 		hash_value = info->hash;
548 		buff = (const u8 *)(get_load_addr() + flash_entry_addr);
549 
550 		if (image_num == 0) {
551 			/*
552 			 * The first image includes hash values in its content.
553 			 * For hash calculation, we need to save the original
554 			 * hash values to a local variable that will be
555 			 * copied back for comparsion and set all zeros to
556 			 * the orignal hash values for calculating new value.
557 			 * First image original format :
558 			 * x...x (datum1) x...x(orig. hash values) x...x(datum2)
559 			 * Replaced first image format :
560 			 * x...x (datum1) 0...0(hash values) x...x(datum2)
561 			 */
562 			memcpy(internal_hash, hash_value,
563 			       sizeof(internal_hash));
564 			memset(hash_value, 0, sizeof(internal_hash));
565 		}
566 		if (image_size_to_hash == 0) {
567 			printf("Warning: Image_%d hash checksum is disabled, ",
568 			       image_num);
569 			printf("skip the image validation.\n");
570 			continue;
571 		}
572 		switch (hash_algorithm_id) {
573 		case SHA1_SUM_LEN:
574 			sha1_starts(&hash1_text);
575 			sha1_update(&hash1_text, buff, image_size_to_hash);
576 			sha1_finish(&hash1_text, hash_160_output);
577 			hash_output = hash_160_output;
578 			break;
579 		case SHA256_SUM_LEN:
580 			sha256_starts(&hash256_text);
581 			sha256_update(&hash256_text, buff, image_size_to_hash);
582 			sha256_finish(&hash256_text, hash_256_output);
583 			hash_output = hash_256_output;
584 			break;
585 		default:
586 			printf("Error: Unsupported hash_algorithm_id = %d\n",
587 			       hash_algorithm_id);
588 			return -ENOEXEC;
589 		}
590 		if (image_num == 0)
591 			memcpy(hash_value, internal_hash,
592 			       sizeof(internal_hash));
593 		if (memcmp(hash_value, hash_output, hash_algorithm_id) != 0) {
594 			printf("Error: Image_%d checksum is not correct\n",
595 			       image_num);
596 			return -ENOEXEC;
597 		}
598 	}
599 	printf("Image checksum...OK!\n");
600 
601 	return 0;
602 }
603 
604 #else /* Not ARMADA? */
605 static int check_image_header(void)
606 {
607 	printf("bubt cmd does not support this SoC device or family!\n");
608 	return -ENOEXEC;
609 }
610 #endif
611 
612 static int bubt_verify(size_t image_size)
613 {
614 	int err;
615 
616 	/* Check a correct image header exists */
617 	err = check_image_header();
618 	if (err) {
619 		printf("Error: Image header verification failed\n");
620 		return err;
621 	}
622 
623 	return 0;
624 }
625 
626 static int bubt_read_file(struct bubt_dev *src)
627 {
628 	size_t image_size;
629 
630 	if (!src->read) {
631 		printf("Error: Read not supported on device \"%s\"\n",
632 		       src->name);
633 		return 0;
634 	}
635 
636 	image_size = src->read(net_boot_file_name);
637 	if (image_size <= 0) {
638 		printf("Error: Failed to read file %s from %s\n",
639 		       net_boot_file_name, src->name);
640 		return 0;
641 	}
642 
643 	return image_size;
644 }
645 
646 static int bubt_is_dev_active(struct bubt_dev *dev)
647 {
648 	if (!dev->active) {
649 		printf("Device \"%s\" not supported by U-BOOT image\n",
650 		       dev->name);
651 		return 0;
652 	}
653 
654 	if (!dev->active()) {
655 		printf("Device \"%s\" is inactive\n", dev->name);
656 		return 0;
657 	}
658 
659 	return 1;
660 }
661 
662 struct bubt_dev *find_bubt_dev(char *dev_name)
663 {
664 	int dev;
665 
666 	for (dev = 0; dev < BUBT_MAX_DEV; dev++) {
667 		if (strcmp(bubt_devs[dev].name, dev_name) == 0)
668 			return &bubt_devs[dev];
669 	}
670 
671 	return 0;
672 }
673 
674 #define DEFAULT_BUBT_SRC "tftp"
675 
676 #ifndef DEFAULT_BUBT_DST
677 #ifdef CONFIG_MVEBU_SPI_BOOT
678 #define DEFAULT_BUBT_DST "spi"
679 #elif defined(CONFIG_MVEBU_NAND_BOOT)
680 #define DEFAULT_BUBT_DST "nand"
681 #elif defined(CONFIG_MVEBU_MMC_BOOT)
682 #define DEFAULT_BUBT_DST "mmc"
683 else
684 #define DEFAULT_BUBT_DST "error"
685 #endif
686 #endif /* DEFAULT_BUBT_DST */
687 
688 int do_bubt_cmd(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
689 {
690 	struct bubt_dev *src, *dst;
691 	size_t image_size;
692 	char src_dev_name[8];
693 	char dst_dev_name[8];
694 	char *name;
695 	int  err;
696 
697 	if (argc < 2)
698 		copy_filename(net_boot_file_name,
699 			      CONFIG_MVEBU_UBOOT_DFLT_NAME,
700 			      sizeof(net_boot_file_name));
701 	else
702 		copy_filename(net_boot_file_name, argv[1],
703 			      sizeof(net_boot_file_name));
704 
705 	if (argc >= 3) {
706 		strncpy(dst_dev_name, argv[2], 8);
707 	} else {
708 		name = DEFAULT_BUBT_DST;
709 		strncpy(dst_dev_name, name, 8);
710 	}
711 
712 	if (argc >= 4)
713 		strncpy(src_dev_name, argv[3], 8);
714 	else
715 		strncpy(src_dev_name, DEFAULT_BUBT_SRC, 8);
716 
717 	/* Figure out the destination device */
718 	dst = find_bubt_dev(dst_dev_name);
719 	if (!dst) {
720 		printf("Error: Unknown destination \"%s\"\n", dst_dev_name);
721 		return -EINVAL;
722 	}
723 
724 	if (!bubt_is_dev_active(dst))
725 		return -ENODEV;
726 
727 	/* Figure out the source device */
728 	src = find_bubt_dev(src_dev_name);
729 	if (!src) {
730 		printf("Error: Unknown source \"%s\"\n", src_dev_name);
731 		return 1;
732 	}
733 
734 	if (!bubt_is_dev_active(src))
735 		return -ENODEV;
736 
737 	printf("Burning U-BOOT image \"%s\" from \"%s\" to \"%s\"\n",
738 	       net_boot_file_name, src->name, dst->name);
739 
740 	image_size = bubt_read_file(src);
741 	if (!image_size)
742 		return -EIO;
743 
744 	err = bubt_verify(image_size);
745 	if (err)
746 		return err;
747 
748 	err = bubt_write_file(dst, image_size);
749 	if (err)
750 		return err;
751 
752 	return 0;
753 }
754 
755 U_BOOT_CMD(
756 	bubt, 4, 0, do_bubt_cmd,
757 	"Burn a u-boot image to flash",
758 	"[file-name] [destination [source]]\n"
759 	"\t-file-name     The image file name to burn. Default = flash-image.bin\n"
760 	"\t-destination   Flash to burn to [spi, nand, mmc]. Default = active boot device\n"
761 	"\t-source        The source to load image from [tftp, usb, mmc]. Default = tftp\n"
762 	"Examples:\n"
763 	"\tbubt - Burn flash-image.bin from tftp to active boot device\n"
764 	"\tbubt flash-image-new.bin nand - Burn flash-image-new.bin from tftp to NAND flash\n"
765 	"\tbubt backup-flash-image.bin mmc usb - Burn backup-flash-image.bin from usb to MMC\n"
766 
767 );
768