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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 #ifdef CONFIG_BLK
22 #include <blk.h>
23 #endif
24 #include <u-boot/sha1.h>
25 #include <u-boot/sha256.h>
26
27 #ifndef CONFIG_SYS_MMC_ENV_DEV
28 #define CONFIG_SYS_MMC_ENV_DEV 0
29 #endif
30
31 #if defined(CONFIG_ARMADA_8K)
32 #define MAIN_HDR_MAGIC 0xB105B002
33
34 struct mvebu_image_header {
35 u32 magic; /* 0-3 */
36 u32 prolog_size; /* 4-7 */
37 u32 prolog_checksum; /* 8-11 */
38 u32 boot_image_size; /* 12-15 */
39 u32 boot_image_checksum; /* 16-19 */
40 u32 rsrvd0; /* 20-23 */
41 u32 load_addr; /* 24-27 */
42 u32 exec_addr; /* 28-31 */
43 u8 uart_cfg; /* 32 */
44 u8 baudrate; /* 33 */
45 u8 ext_count; /* 34 */
46 u8 aux_flags; /* 35 */
47 u32 io_arg_0; /* 36-39 */
48 u32 io_arg_1; /* 40-43 */
49 u32 io_arg_2; /* 43-47 */
50 u32 io_arg_3; /* 48-51 */
51 u32 rsrvd1; /* 52-55 */
52 u32 rsrvd2; /* 56-59 */
53 u32 rsrvd3; /* 60-63 */
54 };
55 #elif defined(CONFIG_ARMADA_3700) /* A3700 */
56 #define HASH_SUM_LEN 16
57 #define IMAGE_VERSION_3_6_0 0x030600
58 #define IMAGE_VERSION_3_5_0 0x030500
59
60 struct common_tim_data {
61 u32 version;
62 u32 identifier;
63 u32 trusted;
64 u32 issue_date;
65 u32 oem_unique_id;
66 u32 reserved[5]; /* Reserve 20 bytes */
67 u32 boot_flash_sign;
68 u32 num_images;
69 u32 num_keys;
70 u32 size_of_reserved;
71 };
72
73 struct mvebu_image_info {
74 u32 image_id;
75 u32 next_image_id;
76 u32 flash_entry_addr;
77 u32 load_addr;
78 u32 image_size;
79 u32 image_size_to_hash;
80 u32 hash_algorithm_id;
81 u32 hash[HASH_SUM_LEN]; /* Reserve 512 bits for the hash */
82 u32 partition_number;
83 u32 enc_algorithm_id;
84 u32 encrypt_start_offset;
85 u32 encrypt_size;
86 };
87 #endif /* CONFIG_ARMADA_XXX */
88
89 struct bubt_dev {
90 char name[8];
91 size_t (*read)(const char *file_name);
92 int (*write)(size_t image_size);
93 int (*active)(void);
94 };
95
96 static ulong get_load_addr(void)
97 {
98 const char *addr_str;
99 unsigned long addr;
100
101 addr_str = env_get("loadaddr");
102 if (addr_str)
103 addr = simple_strtoul(addr_str, NULL, 16);
104 else
105 addr = CONFIG_SYS_LOAD_ADDR;
106
107 return addr;
108 }
109
110 /********************************************************************
111 * eMMC services
112 ********************************************************************/
113 #ifdef CONFIG_DM_MMC
114 static int mmc_burn_image(size_t image_size)
115 {
116 struct mmc *mmc;
117 lbaint_t start_lba;
118 lbaint_t blk_count;
119 ulong blk_written;
120 int err;
121 const u8 mmc_dev_num = CONFIG_SYS_MMC_ENV_DEV;
122 #ifdef CONFIG_BLK
123 struct blk_desc *blk_desc;
124 #endif
125 mmc = find_mmc_device(mmc_dev_num);
126 if (!mmc) {
127 printf("No SD/MMC/eMMC card found\n");
128 return -ENOMEDIUM;
129 }
130
131 err = mmc_init(mmc);
132 if (err) {
133 printf("%s(%d) init failed\n", IS_SD(mmc) ? "SD" : "MMC",
134 mmc_dev_num);
135 return err;
136 }
137
138 #ifdef CONFIG_SYS_MMC_ENV_PART
139 if (mmc->part_num != CONFIG_SYS_MMC_ENV_PART) {
140 err = mmc_switch_part(mmc_dev_num, CONFIG_SYS_MMC_ENV_PART);
141 if (err) {
142 printf("MMC partition switch failed\n");
143 return err;
144 }
145 }
146 #endif
147
148 /* SD reserves LBA-0 for MBR and boots from LBA-1,
149 * MMC/eMMC boots from LBA-0
150 */
151 start_lba = IS_SD(mmc) ? 1 : 0;
152 #ifdef CONFIG_BLK
153 blk_count = image_size / mmc->write_bl_len;
154 if (image_size % mmc->write_bl_len)
155 blk_count += 1;
156
157 blk_desc = mmc_get_blk_desc(mmc);
158 if (!blk_desc) {
159 printf("Error - failed to obtain block descriptor\n");
160 return -ENODEV;
161 }
162 blk_written = blk_dwrite(blk_desc, start_lba, blk_count,
163 (void *)get_load_addr());
164 #else
165 blk_count = image_size / mmc->block_dev.blksz;
166 if (image_size % mmc->block_dev.blksz)
167 blk_count += 1;
168
169 blk_written = mmc->block_dev.block_write(mmc_dev_num,
170 start_lba, blk_count,
171 (void *)get_load_addr());
172 #endif /* CONFIG_BLK */
173 if (blk_written != blk_count) {
174 printf("Error - written %#lx blocks\n", blk_written);
175 return -ENOSPC;
176 }
177 printf("Done!\n");
178
179 #ifdef CONFIG_SYS_MMC_ENV_PART
180 if (mmc->part_num != CONFIG_SYS_MMC_ENV_PART)
181 mmc_switch_part(mmc_dev_num, mmc->part_num);
182 #endif
183
184 return 0;
185 }
186
187 static size_t mmc_read_file(const char *file_name)
188 {
189 loff_t act_read = 0;
190 int rc;
191 struct mmc *mmc;
192 const u8 mmc_dev_num = CONFIG_SYS_MMC_ENV_DEV;
193
194 mmc = find_mmc_device(mmc_dev_num);
195 if (!mmc) {
196 printf("No SD/MMC/eMMC card found\n");
197 return 0;
198 }
199
200 if (mmc_init(mmc)) {
201 printf("%s(%d) init failed\n", IS_SD(mmc) ? "SD" : "MMC",
202 mmc_dev_num);
203 return 0;
204 }
205
206 /* Load from data partition (0) */
207 if (fs_set_blk_dev("mmc", "0", FS_TYPE_ANY)) {
208 printf("Error: MMC 0 not found\n");
209 return 0;
210 }
211
212 /* Perfrom file read */
213 rc = fs_read(file_name, get_load_addr(), 0, 0, &act_read);
214 if (rc)
215 return 0;
216
217 return act_read;
218 }
219
220 static int is_mmc_active(void)
221 {
222 return 1;
223 }
224 #else /* CONFIG_DM_MMC */
225 static int mmc_burn_image(size_t image_size)
226 {
227 return -ENODEV;
228 }
229
230 static size_t mmc_read_file(const char *file_name)
231 {
232 return 0;
233 }
234
235 static int is_mmc_active(void)
236 {
237 return 0;
238 }
239 #endif /* CONFIG_DM_MMC */
240
241 /********************************************************************
242 * SPI services
243 ********************************************************************/
244 #ifdef CONFIG_SPI_FLASH
245 static int spi_burn_image(size_t image_size)
246 {
247 int ret;
248 struct spi_flash *flash;
249 u32 erase_bytes;
250
251 /* Probe the SPI bus to get the flash device */
252 flash = spi_flash_probe(CONFIG_ENV_SPI_BUS,
253 CONFIG_ENV_SPI_CS,
254 CONFIG_SF_DEFAULT_SPEED,
255 CONFIG_SF_DEFAULT_MODE);
256 if (!flash) {
257 printf("Failed to probe SPI Flash\n");
258 return -ENOMEDIUM;
259 }
260
261 #ifdef CONFIG_SPI_FLASH_PROTECTION
262 spi_flash_protect(flash, 0);
263 #endif
264 erase_bytes = image_size +
265 (flash->erase_size - image_size % flash->erase_size);
266 printf("Erasing %d bytes (%d blocks) at offset 0 ...",
267 erase_bytes, erase_bytes / flash->erase_size);
268 ret = spi_flash_erase(flash, 0, erase_bytes);
269 if (ret)
270 printf("Error!\n");
271 else
272 printf("Done!\n");
273
274 printf("Writing %d bytes from 0x%lx to offset 0 ...",
275 (int)image_size, get_load_addr());
276 ret = spi_flash_write(flash, 0, image_size, (void *)get_load_addr());
277 if (ret)
278 printf("Error!\n");
279 else
280 printf("Done!\n");
281
282 #ifdef CONFIG_SPI_FLASH_PROTECTION
283 spi_flash_protect(flash, 1);
284 #endif
285
286 return ret;
287 }
288
289 static int is_spi_active(void)
290 {
291 return 1;
292 }
293
294 #else /* CONFIG_SPI_FLASH */
295 static int spi_burn_image(size_t image_size)
296 {
297 return -ENODEV;
298 }
299
300 static int is_spi_active(void)
301 {
302 return 0;
303 }
304 #endif /* CONFIG_SPI_FLASH */
305
306 /********************************************************************
307 * NAND services
308 ********************************************************************/
309 #ifdef CONFIG_CMD_NAND
310 static int nand_burn_image(size_t image_size)
311 {
312 int ret;
313 uint32_t block_size;
314 struct mtd_info *mtd;
315
316 mtd = get_nand_dev_by_index(nand_curr_device);
317 if (!mtd) {
318 puts("\nno devices available\n");
319 return -ENOMEDIUM;
320 }
321 block_size = mtd->erasesize;
322
323 /* Align U-Boot size to currently used blocksize */
324 image_size = ((image_size + (block_size - 1)) & (~(block_size - 1)));
325
326 /* Erase the U-BOOT image space */
327 printf("Erasing 0x%x - 0x%x:...", 0, (int)image_size);
328 ret = nand_erase(mtd, 0, image_size);
329 if (ret) {
330 printf("Error!\n");
331 goto error;
332 }
333 printf("Done!\n");
334
335 /* Write the image to flash */
336 printf("Writing %d bytes from 0x%lx to offset 0 ... ",
337 (int)image_size, get_load_addr());
338 ret = nand_write(mtd, 0, &image_size, (void *)get_load_addr());
339 if (ret)
340 printf("Error!\n");
341 else
342 printf("Done!\n");
343
344 error:
345 return ret;
346 }
347
348 static int is_nand_active(void)
349 {
350 return 1;
351 }
352
353 #else /* CONFIG_CMD_NAND */
354 static int nand_burn_image(size_t image_size)
355 {
356 return -ENODEV;
357 }
358
359 static int is_nand_active(void)
360 {
361 return 0;
362 }
363 #endif /* CONFIG_CMD_NAND */
364
365 /********************************************************************
366 * USB services
367 ********************************************************************/
368 #if defined(CONFIG_USB_STORAGE) && defined(CONFIG_BLK)
369 static size_t usb_read_file(const char *file_name)
370 {
371 loff_t act_read = 0;
372 struct udevice *dev;
373 int rc;
374
375 usb_stop();
376
377 if (usb_init() < 0) {
378 printf("Error: usb_init failed\n");
379 return 0;
380 }
381
382 /* Try to recognize storage devices immediately */
383 blk_first_device(IF_TYPE_USB, &dev);
384 if (!dev) {
385 printf("Error: USB storage device not found\n");
386 return 0;
387 }
388
389 /* Always load from usb 0 */
390 if (fs_set_blk_dev("usb", "0", FS_TYPE_ANY)) {
391 printf("Error: USB 0 not found\n");
392 return 0;
393 }
394
395 /* Perfrom file read */
396 rc = fs_read(file_name, get_load_addr(), 0, 0, &act_read);
397 if (rc)
398 return 0;
399
400 return act_read;
401 }
402
403 static int is_usb_active(void)
404 {
405 return 1;
406 }
407
408 #else /* defined(CONFIG_USB_STORAGE) && defined (CONFIG_BLK) */
409 static size_t usb_read_file(const char *file_name)
410 {
411 return 0;
412 }
413
414 static int is_usb_active(void)
415 {
416 return 0;
417 }
418 #endif /* defined(CONFIG_USB_STORAGE) && defined (CONFIG_BLK) */
419
420 /********************************************************************
421 * Network services
422 ********************************************************************/
423 #ifdef CONFIG_CMD_NET
424 static size_t tftp_read_file(const char *file_name)
425 {
426 /* update global variable load_addr before tftp file from network */
427 load_addr = get_load_addr();
428 return net_loop(TFTPGET);
429 }
430
431 static int is_tftp_active(void)
432 {
433 return 1;
434 }
435
436 #else
437 static size_t tftp_read_file(const char *file_name)
438 {
439 return 0;
440 }
441
442 static int is_tftp_active(void)
443 {
444 return 0;
445 }
446 #endif /* CONFIG_CMD_NET */
447
448 enum bubt_devices {
449 BUBT_DEV_NET = 0,
450 BUBT_DEV_USB,
451 BUBT_DEV_MMC,
452 BUBT_DEV_SPI,
453 BUBT_DEV_NAND,
454
455 BUBT_MAX_DEV
456 };
457
458 struct bubt_dev bubt_devs[BUBT_MAX_DEV] = {
459 {"tftp", tftp_read_file, NULL, is_tftp_active},
460 {"usb", usb_read_file, NULL, is_usb_active},
461 {"mmc", mmc_read_file, mmc_burn_image, is_mmc_active},
462 {"spi", NULL, spi_burn_image, is_spi_active},
463 {"nand", NULL, nand_burn_image, is_nand_active},
464 };
465
466 static int bubt_write_file(struct bubt_dev *dst, size_t image_size)
467 {
468 if (!dst->write) {
469 printf("Error: Write not supported on device %s\n", dst->name);
470 return -ENOTSUPP;
471 }
472
473 return dst->write(image_size);
474 }
475
476 #if defined(CONFIG_ARMADA_8K)
477 u32 do_checksum32(u32 *start, int32_t len)
478 {
479 u32 sum = 0;
480 u32 *startp = start;
481
482 do {
483 sum += *startp;
484 startp++;
485 len -= 4;
486 } while (len > 0);
487
488 return sum;
489 }
490
491 static int check_image_header(void)
492 {
493 struct mvebu_image_header *hdr =
494 (struct mvebu_image_header *)get_load_addr();
495 u32 header_len = hdr->prolog_size;
496 u32 checksum;
497 u32 checksum_ref = hdr->prolog_checksum;
498
499 /*
500 * For now compare checksum, and magic. Later we can
501 * verify more stuff on the header like interface type, etc
502 */
503 if (hdr->magic != MAIN_HDR_MAGIC) {
504 printf("ERROR: Bad MAGIC 0x%08x != 0x%08x\n",
505 hdr->magic, MAIN_HDR_MAGIC);
506 return -ENOEXEC;
507 }
508
509 /* The checksum value is discarded from checksum calculation */
510 hdr->prolog_checksum = 0;
511
512 checksum = do_checksum32((u32 *)hdr, header_len);
513 if (checksum != checksum_ref) {
514 printf("Error: Bad Image checksum. 0x%x != 0x%x\n",
515 checksum, checksum_ref);
516 return -ENOEXEC;
517 }
518
519 /* Restore the checksum before writing */
520 hdr->prolog_checksum = checksum_ref;
521 printf("Image checksum...OK!\n");
522
523 return 0;
524 }
525 #elif defined(CONFIG_ARMADA_3700) /* Armada 3700 */
526 static int check_image_header(void)
527 {
528 struct common_tim_data *hdr = (struct common_tim_data *)get_load_addr();
529 int image_num;
530 u8 hash_160_output[SHA1_SUM_LEN];
531 u8 hash_256_output[SHA256_SUM_LEN];
532 sha1_context hash1_text;
533 sha256_context hash256_text;
534 u8 *hash_output;
535 u32 hash_algorithm_id;
536 u32 image_size_to_hash;
537 u32 flash_entry_addr;
538 u32 *hash_value;
539 u32 internal_hash[HASH_SUM_LEN];
540 const u8 *buff;
541 u32 num_of_image = hdr->num_images;
542 u32 version = hdr->version;
543 u32 trusted = hdr->trusted;
544
545 /* bubt checksum validation only supports nontrusted images */
546 if (trusted == 1) {
547 printf("bypass image validation, ");
548 printf("only untrusted image is supported now\n");
549 return 0;
550 }
551 /* only supports image version 3.5 and 3.6 */
552 if (version != IMAGE_VERSION_3_5_0 && version != IMAGE_VERSION_3_6_0) {
553 printf("Error: Unsupported Image version = 0x%08x\n", version);
554 return -ENOEXEC;
555 }
556 /* validate images hash value */
557 for (image_num = 0; image_num < num_of_image; image_num++) {
558 struct mvebu_image_info *info =
559 (struct mvebu_image_info *)(get_load_addr() +
560 sizeof(struct common_tim_data) +
561 image_num * sizeof(struct mvebu_image_info));
562 hash_algorithm_id = info->hash_algorithm_id;
563 image_size_to_hash = info->image_size_to_hash;
564 flash_entry_addr = info->flash_entry_addr;
565 hash_value = info->hash;
566 buff = (const u8 *)(get_load_addr() + flash_entry_addr);
567
568 if (image_num == 0) {
569 /*
570 * The first image includes hash values in its content.
571 * For hash calculation, we need to save the original
572 * hash values to a local variable that will be
573 * copied back for comparsion and set all zeros to
574 * the orignal hash values for calculating new value.
575 * First image original format :
576 * x...x (datum1) x...x(orig. hash values) x...x(datum2)
577 * Replaced first image format :
578 * x...x (datum1) 0...0(hash values) x...x(datum2)
579 */
580 memcpy(internal_hash, hash_value,
581 sizeof(internal_hash));
582 memset(hash_value, 0, sizeof(internal_hash));
583 }
584 if (image_size_to_hash == 0) {
585 printf("Warning: Image_%d hash checksum is disabled, ",
586 image_num);
587 printf("skip the image validation.\n");
588 continue;
589 }
590 switch (hash_algorithm_id) {
591 case SHA1_SUM_LEN:
592 sha1_starts(&hash1_text);
593 sha1_update(&hash1_text, buff, image_size_to_hash);
594 sha1_finish(&hash1_text, hash_160_output);
595 hash_output = hash_160_output;
596 break;
597 case SHA256_SUM_LEN:
598 sha256_starts(&hash256_text);
599 sha256_update(&hash256_text, buff, image_size_to_hash);
600 sha256_finish(&hash256_text, hash_256_output);
601 hash_output = hash_256_output;
602 break;
603 default:
604 printf("Error: Unsupported hash_algorithm_id = %d\n",
605 hash_algorithm_id);
606 return -ENOEXEC;
607 }
608 if (image_num == 0)
609 memcpy(hash_value, internal_hash,
610 sizeof(internal_hash));
611 if (memcmp(hash_value, hash_output, hash_algorithm_id) != 0) {
612 printf("Error: Image_%d checksum is not correct\n",
613 image_num);
614 return -ENOEXEC;
615 }
616 }
617 printf("Image checksum...OK!\n");
618
619 return 0;
620 }
621
622 #else /* Not ARMADA? */
623 static int check_image_header(void)
624 {
625 printf("bubt cmd does not support this SoC device or family!\n");
626 return -ENOEXEC;
627 }
628 #endif
629
630 static int bubt_verify(size_t image_size)
631 {
632 int err;
633
634 /* Check a correct image header exists */
635 err = check_image_header();
636 if (err) {
637 printf("Error: Image header verification failed\n");
638 return err;
639 }
640
641 return 0;
642 }
643
644 static int bubt_read_file(struct bubt_dev *src)
645 {
646 size_t image_size;
647
648 if (!src->read) {
649 printf("Error: Read not supported on device \"%s\"\n",
650 src->name);
651 return 0;
652 }
653
654 image_size = src->read(net_boot_file_name);
655 if (image_size <= 0) {
656 printf("Error: Failed to read file %s from %s\n",
657 net_boot_file_name, src->name);
658 return 0;
659 }
660
661 return image_size;
662 }
663
664 static int bubt_is_dev_active(struct bubt_dev *dev)
665 {
666 if (!dev->active) {
667 printf("Device \"%s\" not supported by U-BOOT image\n",
668 dev->name);
669 return 0;
670 }
671
672 if (!dev->active()) {
673 printf("Device \"%s\" is inactive\n", dev->name);
674 return 0;
675 }
676
677 return 1;
678 }
679
680 struct bubt_dev *find_bubt_dev(char *dev_name)
681 {
682 int dev;
683
684 for (dev = 0; dev < BUBT_MAX_DEV; dev++) {
685 if (strcmp(bubt_devs[dev].name, dev_name) == 0)
686 return &bubt_devs[dev];
687 }
688
689 return 0;
690 }
691
692 #define DEFAULT_BUBT_SRC "tftp"
693
694 #ifndef DEFAULT_BUBT_DST
695 #ifdef CONFIG_MVEBU_SPI_BOOT
696 #define DEFAULT_BUBT_DST "spi"
697 #elif defined(CONFIG_MVEBU_NAND_BOOT)
698 #define DEFAULT_BUBT_DST "nand"
699 #elif defined(CONFIG_MVEBU_MMC_BOOT)
700 #define DEFAULT_BUBT_DST "mmc"
701 else
702 #define DEFAULT_BUBT_DST "error"
703 #endif
704 #endif /* DEFAULT_BUBT_DST */
705
706 int do_bubt_cmd(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
707 {
708 struct bubt_dev *src, *dst;
709 size_t image_size;
710 char src_dev_name[8];
711 char dst_dev_name[8];
712 char *name;
713 int err;
714
715 if (argc < 2)
716 copy_filename(net_boot_file_name,
717 CONFIG_MVEBU_UBOOT_DFLT_NAME,
718 sizeof(net_boot_file_name));
719 else
720 copy_filename(net_boot_file_name, argv[1],
721 sizeof(net_boot_file_name));
722
723 if (argc >= 3) {
724 strncpy(dst_dev_name, argv[2], 8);
725 } else {
726 name = DEFAULT_BUBT_DST;
727 strncpy(dst_dev_name, name, 8);
728 }
729
730 if (argc >= 4)
731 strncpy(src_dev_name, argv[3], 8);
732 else
733 strncpy(src_dev_name, DEFAULT_BUBT_SRC, 8);
734
735 /* Figure out the destination device */
736 dst = find_bubt_dev(dst_dev_name);
737 if (!dst) {
738 printf("Error: Unknown destination \"%s\"\n", dst_dev_name);
739 return -EINVAL;
740 }
741
742 if (!bubt_is_dev_active(dst))
743 return -ENODEV;
744
745 /* Figure out the source device */
746 src = find_bubt_dev(src_dev_name);
747 if (!src) {
748 printf("Error: Unknown source \"%s\"\n", src_dev_name);
749 return 1;
750 }
751
752 if (!bubt_is_dev_active(src))
753 return -ENODEV;
754
755 printf("Burning U-BOOT image \"%s\" from \"%s\" to \"%s\"\n",
756 net_boot_file_name, src->name, dst->name);
757
758 image_size = bubt_read_file(src);
759 if (!image_size)
760 return -EIO;
761
762 err = bubt_verify(image_size);
763 if (err)
764 return err;
765
766 err = bubt_write_file(dst, image_size);
767 if (err)
768 return err;
769
770 return 0;
771 }
772
773 U_BOOT_CMD(
774 bubt, 4, 0, do_bubt_cmd,
775 "Burn a u-boot image to flash",
776 "[file-name] [destination [source]]\n"
777 "\t-file-name The image file name to burn. Default = flash-image.bin\n"
778 "\t-destination Flash to burn to [spi, nand, mmc]. Default = active boot device\n"
779 "\t-source The source to load image from [tftp, usb, mmc]. Default = tftp\n"
780 "Examples:\n"
781 "\tbubt - Burn flash-image.bin from tftp to active boot device\n"
782 "\tbubt flash-image-new.bin nand - Burn flash-image-new.bin from tftp to NAND flash\n"
783 "\tbubt backup-flash-image.bin mmc usb - Burn backup-flash-image.bin from usb to MMC\n"
784
785 );