2 * Driver for NAND support, Rick Bronson
3 * borrowed heavily from:
4 * (c) 1999 Machine Vision Holdings, Inc.
5 * (c) 1999, 2000 David Woodhouse <dwmw2@infradead.org>
7 * Ported 'dynenv' to 'nand env.oob' command
8 * (C) 2010 Nanometrics, Inc.
9 * 'dynenv' -- Dynamic environment offset in NAND OOB
10 * (C) Copyright 2006-2007 OpenMoko, Inc.
11 * Added 16-bit nand support
12 * (C) 2004 Texas Instruments
14 * Copyright 2010, 2012 Freescale Semiconductor
15 * The portions of this file whose copyright is held by Freescale and which
16 * are not considered a derived work of GPL v2-only code may be distributed
17 * and/or modified under the terms of the GNU General Public License as
18 * published by the Free Software Foundation; either version 2 of the
19 * License, or (at your option) any later version.
23 #include <linux/mtd/mtd.h>
27 #include <asm/byteorder.h>
28 #include <jffs2/jffs2.h>
31 #if defined(CONFIG_CMD_MTDPARTS)
33 /* partition handling routines */
34 int mtdparts_init(void);
35 int id_parse(const char *id, const char **ret_id, u8 *dev_type, u8 *dev_num);
36 int find_dev_and_part(const char *id, struct mtd_device **dev,
37 u8 *part_num, struct part_info **part);
40 static int nand_dump(nand_info_t *nand, ulong off, int only_oob, int repeat)
43 u_char *datbuf, *oobbuf, *p;
47 off = last + nand->writesize;
51 datbuf = malloc(nand->writesize);
52 oobbuf = malloc(nand->oobsize);
53 if (!datbuf || !oobbuf) {
54 puts("No memory for page buffer\n");
57 off &= ~(nand->writesize - 1);
58 loff_t addr = (loff_t) off;
59 struct mtd_oob_ops ops;
60 memset(&ops, 0, sizeof(ops));
63 ops.len = nand->writesize;
64 ops.ooblen = nand->oobsize;
65 ops.mode = MTD_OOB_RAW;
66 i = nand->read_oob(nand, addr, &ops);
68 printf("Error (%d) reading page %08lx\n", i, off);
73 printf("Page %08lx dump:\n", off);
74 i = nand->writesize >> 4;
79 printf("\t%02x %02x %02x %02x %02x %02x %02x %02x"
80 " %02x %02x %02x %02x %02x %02x %02x %02x\n",
81 p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7],
82 p[8], p[9], p[10], p[11], p[12], p[13], p[14],
87 i = nand->oobsize >> 3;
90 printf("\t%02x %02x %02x %02x %02x %02x %02x %02x\n",
91 p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7]);
100 /* ------------------------------------------------------------------------- */
102 static int set_dev(int dev)
104 if (dev < 0 || dev >= CONFIG_SYS_MAX_NAND_DEVICE ||
105 !nand_info[dev].name) {
106 puts("No such device\n");
110 if (nand_curr_device == dev)
113 printf("Device %d: %s", dev, nand_info[dev].name);
114 puts("... is now current device\n");
115 nand_curr_device = dev;
117 #ifdef CONFIG_SYS_NAND_SELECT_DEVICE
118 board_nand_select_device(nand_info[dev].priv, dev);
124 static inline int str2off(const char *p, loff_t *num)
128 *num = simple_strtoull(p, &endptr, 16);
129 return *p != '\0' && *endptr == '\0';
132 static inline int str2long(const char *p, ulong *num)
136 *num = simple_strtoul(p, &endptr, 16);
137 return *p != '\0' && *endptr == '\0';
140 static int get_part(const char *partname, int *idx, loff_t *off, loff_t *size)
142 #ifdef CONFIG_CMD_MTDPARTS
143 struct mtd_device *dev;
144 struct part_info *part;
148 ret = mtdparts_init();
152 ret = find_dev_and_part(partname, &dev, &pnum, &part);
156 if (dev->id->type != MTD_DEV_TYPE_NAND) {
157 puts("not a NAND device\n");
171 puts("offset is not a number\n");
176 static int arg_off(const char *arg, int *idx, loff_t *off, loff_t *maxsize)
178 if (!str2off(arg, off))
179 return get_part(arg, idx, off, maxsize);
181 if (*off >= nand_info[*idx].size) {
182 puts("Offset exceeds device limit\n");
186 *maxsize = nand_info[*idx].size - *off;
190 static int arg_off_size(int argc, char *const argv[], int *idx,
191 loff_t *off, loff_t *size)
198 *size = nand_info[*idx].size;
202 ret = arg_off(argv[0], idx, off, &maxsize);
211 if (!str2off(argv[1], size)) {
212 printf("'%s' is not a number\n", argv[1]);
216 if (*size > maxsize) {
217 puts("Size exceeds partition or device limit\n");
222 printf("device %d ", *idx);
223 if (*size == nand_info[*idx].size)
224 puts("whole chip\n");
226 printf("offset 0x%llx, size 0x%llx\n",
227 (unsigned long long)*off, (unsigned long long)*size);
231 #ifdef CONFIG_CMD_NAND_LOCK_UNLOCK
232 static void print_status(ulong start, ulong end, ulong erasesize, int status)
234 printf("%08lx - %08lx: %08lx blocks %s%s%s\n",
237 (end - start) / erasesize,
238 ((status & NAND_LOCK_STATUS_TIGHT) ? "TIGHT " : ""),
239 ((status & NAND_LOCK_STATUS_LOCK) ? "LOCK " : ""),
240 ((status & NAND_LOCK_STATUS_UNLOCK) ? "UNLOCK " : ""));
243 static void do_nand_status(nand_info_t *nand)
245 ulong block_start = 0;
247 int last_status = -1;
249 struct nand_chip *nand_chip = nand->priv;
250 /* check the WP bit */
251 nand_chip->cmdfunc(nand, NAND_CMD_STATUS, -1, -1);
252 printf("device is %swrite protected\n",
253 (nand_chip->read_byte(nand) & 0x80 ?
256 for (off = 0; off < nand->size; off += nand->erasesize) {
257 int s = nand_get_lock_status(nand, off);
259 /* print message only if status has changed */
260 if (s != last_status && off != 0) {
261 print_status(block_start, off, nand->erasesize,
267 /* Print the last block info */
268 print_status(block_start, off, nand->erasesize, last_status);
272 #ifdef CONFIG_ENV_OFFSET_OOB
273 unsigned long nand_env_oob_offset;
275 int do_nand_env_oob(cmd_tbl_t *cmdtp, int argc, char *const argv[])
278 uint32_t oob_buf[ENV_OFFSET_SIZE/sizeof(uint32_t)];
279 nand_info_t *nand = &nand_info[0];
282 if (CONFIG_SYS_MAX_NAND_DEVICE == 0 || !nand->name) {
283 puts("no devices available\n");
289 if (!strcmp(cmd, "get")) {
290 ret = get_nand_env_oob(nand, &nand_env_oob_offset);
294 printf("0x%08lx\n", nand_env_oob_offset);
295 } else if (!strcmp(cmd, "set")) {
298 struct mtd_oob_ops ops;
304 if (arg_off(argv[2], &idx, &addr, &maxsize)) {
305 puts("Offset or partition name expected\n");
310 puts("Partition not on first NAND device\n");
314 if (nand->oobavail < ENV_OFFSET_SIZE) {
315 printf("Insufficient available OOB bytes:\n"
316 "%d OOB bytes available but %d required for "
318 nand->oobavail, ENV_OFFSET_SIZE);
322 if ((addr & (nand->erasesize - 1)) != 0) {
323 printf("Environment offset must be block-aligned\n");
328 ops.mode = MTD_OOB_AUTO;
330 ops.ooblen = ENV_OFFSET_SIZE;
331 ops.oobbuf = (void *) oob_buf;
333 oob_buf[0] = ENV_OOB_MARKER;
334 oob_buf[1] = addr / nand->erasesize;
336 ret = nand->write_oob(nand, ENV_OFFSET_SIZE, &ops);
338 printf("Error writing OOB block 0\n");
342 ret = get_nand_env_oob(nand, &nand_env_oob_offset);
344 printf("Error reading env offset in OOB\n");
348 if (addr != nand_env_oob_offset) {
349 printf("Verification of env offset in OOB failed: "
350 "0x%08llx expected but got 0x%08lx\n",
351 (unsigned long long)addr, nand_env_oob_offset);
361 return CMD_RET_USAGE;
366 static void nand_print_and_set_info(int idx)
368 nand_info_t *nand = &nand_info[idx];
369 struct nand_chip *chip = nand->priv;
370 const int bufsz = 32;
373 printf("Device %d: ", idx);
374 if (chip->numchips > 1)
375 printf("%dx ", chip->numchips);
376 printf("%s, sector size %u KiB\n",
377 nand->name, nand->erasesize >> 10);
378 printf(" Page size %8d b\n", nand->writesize);
379 printf(" OOB size %8d b\n", nand->oobsize);
380 printf(" Erase size %8d b\n", nand->erasesize);
382 /* Set geometry info */
383 sprintf(buf, "%x", nand->writesize);
384 setenv("nand_writesize", buf);
386 sprintf(buf, "%x", nand->oobsize);
387 setenv("nand_oobsize", buf);
389 sprintf(buf, "%x", nand->erasesize);
390 setenv("nand_erasesize", buf);
393 static int raw_access(nand_info_t *nand, ulong addr, loff_t off, ulong count,
400 mtd_oob_ops_t ops = {
401 .datbuf = (u8 *)addr,
402 .oobbuf = ((u8 *)addr) + nand->writesize,
403 .len = nand->writesize,
404 .ooblen = nand->oobsize,
409 ret = nand->read_oob(nand, off, &ops);
411 ret = nand->write_oob(nand, off, &ops);
414 printf("%s: error at offset %llx, ret %d\n",
415 __func__, (long long)off, ret);
419 addr += nand->writesize + nand->oobsize;
420 off += nand->writesize;
426 int do_nand(cmd_tbl_t * cmdtp, int flag, int argc, char * const argv[])
433 #ifdef CONFIG_SYS_NAND_QUIET
434 int quiet = CONFIG_SYS_NAND_QUIET;
438 const char *quiet_str = getenv("quiet");
439 int dev = nand_curr_device;
440 int repeat = flag & CMD_FLAG_REPEAT;
442 /* at least two arguments please */
447 quiet = simple_strtoul(quiet_str, NULL, 0) != 0;
451 /* Only "dump" is repeatable. */
452 if (repeat && strcmp(cmd, "dump"))
455 if (strcmp(cmd, "info") == 0) {
458 for (i = 0; i < CONFIG_SYS_MAX_NAND_DEVICE; i++) {
459 if (nand_info[i].name)
460 nand_print_and_set_info(i);
465 if (strcmp(cmd, "device") == 0) {
468 if (dev < 0 || dev >= CONFIG_SYS_MAX_NAND_DEVICE)
469 puts("no devices available\n");
471 nand_print_and_set_info(dev);
475 dev = (int)simple_strtoul(argv[2], NULL, 10);
481 #ifdef CONFIG_ENV_OFFSET_OOB
482 /* this command operates only on the first nand device */
483 if (strcmp(cmd, "env.oob") == 0)
484 return do_nand_env_oob(cmdtp, argc - 1, argv + 1);
487 /* The following commands operate on the current device, unless
488 * overridden by a partition specifier. Note that if somehow the
489 * current device is invalid, it will have to be changed to a valid
490 * one before these commands can run, even if a partition specifier
491 * for another device is to be used.
493 if (dev < 0 || dev >= CONFIG_SYS_MAX_NAND_DEVICE ||
494 !nand_info[dev].name) {
495 puts("\nno devices available\n");
498 nand = &nand_info[dev];
500 if (strcmp(cmd, "bad") == 0) {
501 printf("\nDevice %d bad blocks:\n", dev);
502 for (off = 0; off < nand->size; off += nand->erasesize)
503 if (nand_block_isbad(nand, off))
504 printf(" %08llx\n", (unsigned long long)off);
511 * nand erase [clean] [off size]
513 if (strncmp(cmd, "erase", 5) == 0 || strncmp(cmd, "scrub", 5) == 0) {
514 nand_erase_options_t opts;
515 /* "clean" at index 2 means request to write cleanmarker */
516 int clean = argc > 2 && !strcmp("clean", argv[2]);
517 int scrub_yes = argc > 2 && !strcmp("-y", argv[2]);
518 int o = (clean || scrub_yes) ? 3 : 2;
519 int scrub = !strncmp(cmd, "scrub", 5);
522 const char *scrub_warn =
524 "scrub option will erase all factory set bad blocks!\n"
526 "There is no reliable way to recover them.\n"
528 "Use this command only for testing purposes if you\n"
530 "are sure of what you are doing!\n"
531 "\nReally scrub this NAND flash? <y/N>\n";
534 if (!strcmp(&cmd[5], ".spread")) {
536 } else if (!strcmp(&cmd[5], ".part")) {
538 } else if (!strcmp(&cmd[5], ".chip")) {
546 * Don't allow missing arguments to cause full chip/partition
547 * erases -- easy to do accidentally, e.g. with a misspelled
550 if (argc != o + args)
553 printf("\nNAND %s: ", cmd);
554 /* skip first two or three arguments, look for offset and size */
555 if (arg_off_size(argc - o, argv + o, &dev, &off, &size) != 0)
558 nand = &nand_info[dev];
560 memset(&opts, 0, sizeof(opts));
565 opts.spread = spread;
573 else if (getc() == 'y') {
578 puts("scrub aborted\n");
582 puts("scrub aborted\n");
586 ret = nand_erase_opts(nand, &opts);
587 printf("%s\n", ret ? "ERROR" : "OK");
589 return ret == 0 ? 0 : 1;
592 if (strncmp(cmd, "dump", 4) == 0) {
596 off = (int)simple_strtoul(argv[2], NULL, 16);
597 ret = nand_dump(nand, off, !strcmp(&cmd[4], ".oob"), repeat);
599 return ret == 0 ? 1 : 0;
602 if (strncmp(cmd, "read", 4) == 0 || strncmp(cmd, "write", 5) == 0) {
611 addr = (ulong)simple_strtoul(argv[2], NULL, 16);
613 read = strncmp(cmd, "read", 4) == 0; /* 1 = read, 0 = write */
614 printf("\nNAND %s: ", read ? "read" : "write");
616 nand = &nand_info[dev];
618 s = strchr(cmd, '.');
620 if (s && !strcmp(s, ".raw")) {
623 if (arg_off(argv[3], &dev, &off, &size))
626 if (argc > 4 && !str2long(argv[4], &pagecount)) {
627 printf("'%s' is not a number\n", argv[4]);
631 if (pagecount * nand->writesize > size) {
632 puts("Size exceeds partition or device limit\n");
636 rwsize = pagecount * (nand->writesize + nand->oobsize);
638 if (arg_off_size(argc - 3, argv + 3, &dev,
645 if (!s || !strcmp(s, ".jffs2") ||
646 !strcmp(s, ".e") || !strcmp(s, ".i")) {
648 ret = nand_read_skip_bad(nand, off, &rwsize,
651 ret = nand_write_skip_bad(nand, off, &rwsize,
653 #ifdef CONFIG_CMD_NAND_TRIMFFS
654 } else if (!strcmp(s, ".trimffs")) {
656 printf("Unknown nand command suffix '%s'\n", s);
659 ret = nand_write_skip_bad(nand, off, &rwsize,
663 #ifdef CONFIG_CMD_NAND_YAFFS
664 } else if (!strcmp(s, ".yaffs")) {
666 printf("Unknown nand command suffix '%s'.\n", s);
669 ret = nand_write_skip_bad(nand, off, &rwsize,
673 } else if (!strcmp(s, ".oob")) {
674 /* out-of-band data */
675 mtd_oob_ops_t ops = {
676 .oobbuf = (u8 *)addr,
682 ret = nand->read_oob(nand, off, &ops);
684 ret = nand->write_oob(nand, off, &ops);
686 ret = raw_access(nand, addr, off, pagecount, read);
688 printf("Unknown nand command suffix '%s'.\n", s);
692 printf(" %zu bytes %s: %s\n", rwsize,
693 read ? "read" : "written", ret ? "ERROR" : "OK");
695 return ret == 0 ? 0 : 1;
698 if (strcmp(cmd, "markbad") == 0) {
706 addr = simple_strtoul(*argv, NULL, 16);
708 if (nand->block_markbad(nand, addr)) {
709 printf("block 0x%08lx NOT marked "
710 "as bad! ERROR %d\n",
714 printf("block 0x%08lx successfully "
724 if (strcmp(cmd, "biterr") == 0) {
729 #ifdef CONFIG_CMD_NAND_LOCK_UNLOCK
730 if (strcmp(cmd, "lock") == 0) {
734 if (!strcmp("tight", argv[2]))
736 if (!strcmp("status", argv[2]))
740 do_nand_status(nand);
742 if (!nand_lock(nand, tight)) {
743 puts("NAND flash successfully locked\n");
745 puts("Error locking NAND flash\n");
752 if (strcmp(cmd, "unlock") == 0) {
753 if (arg_off_size(argc - 2, argv + 2, &dev, &off, &size) < 0)
756 if (!nand_unlock(&nand_info[dev], off, size)) {
757 puts("NAND flash successfully unlocked\n");
759 puts("Error unlocking NAND flash, "
760 "write and erase will probably fail\n");
768 return CMD_RET_USAGE;
772 nand, CONFIG_SYS_MAXARGS, 1, do_nand,
774 "info - show available NAND devices\n"
775 "nand device [dev] - show or set current device\n"
776 "nand read - addr off|partition size\n"
777 "nand write - addr off|partition size\n"
778 " read/write 'size' bytes starting at offset 'off'\n"
779 " to/from memory address 'addr', skipping bad blocks.\n"
780 "nand read.raw - addr off|partition [count]\n"
781 "nand write.raw - addr off|partition [count]\n"
782 " Use read.raw/write.raw to avoid ECC and access the flash as-is.\n"
783 #ifdef CONFIG_CMD_NAND_TRIMFFS
784 "nand write.trimffs - addr off|partition size\n"
785 " write 'size' bytes starting at offset 'off' from memory address\n"
786 " 'addr', skipping bad blocks and dropping any pages at the end\n"
787 " of eraseblocks that contain only 0xFF\n"
789 #ifdef CONFIG_CMD_NAND_YAFFS
790 "nand write.yaffs - addr off|partition size\n"
791 " write 'size' bytes starting at offset 'off' with yaffs format\n"
792 " from memory address 'addr', skipping bad blocks.\n"
794 "nand erase[.spread] [clean] off size - erase 'size' bytes "
795 "from offset 'off'\n"
796 " With '.spread', erase enough for given file size, otherwise,\n"
797 " 'size' includes skipped bad blocks.\n"
798 "nand erase.part [clean] partition - erase entire mtd partition'\n"
799 "nand erase.chip [clean] - erase entire chip'\n"
800 "nand bad - show bad blocks\n"
801 "nand dump[.oob] off - dump page\n"
802 "nand scrub [-y] off size | scrub.part partition | scrub.chip\n"
803 " really clean NAND erasing bad blocks (UNSAFE)\n"
804 "nand markbad off [...] - mark bad block(s) at offset (UNSAFE)\n"
805 "nand biterr off - make a bit error at offset (UNSAFE)"
806 #ifdef CONFIG_CMD_NAND_LOCK_UNLOCK
808 "nand lock [tight] [status]\n"
809 " bring nand to lock state or display locked pages\n"
810 "nand unlock [offset] [size] - unlock section"
812 #ifdef CONFIG_ENV_OFFSET_OOB
814 "nand env.oob - environment offset in OOB of block 0 of"
816 "nand env.oob set off|partition - set enviromnent offset\n"
817 "nand env.oob get - get environment offset"
821 static int nand_load_image(cmd_tbl_t *cmdtp, nand_info_t *nand,
822 ulong offset, ulong addr, char *cmd)
828 #if defined(CONFIG_FIT)
829 const void *fit_hdr = NULL;
832 s = strchr(cmd, '.');
834 (strcmp(s, ".jffs2") && strcmp(s, ".e") && strcmp(s, ".i"))) {
835 printf("Unknown nand load suffix '%s'\n", s);
836 bootstage_error(BOOTSTAGE_ID_NAND_SUFFIX);
840 printf("\nLoading from %s, offset 0x%lx\n", nand->name, offset);
842 cnt = nand->writesize;
843 r = nand_read_skip_bad(nand, offset, &cnt, (u_char *) addr);
845 puts("** Read error\n");
846 bootstage_error(BOOTSTAGE_ID_NAND_HDR_READ);
849 bootstage_mark(BOOTSTAGE_ID_NAND_HDR_READ);
851 switch (genimg_get_format ((void *)addr)) {
852 case IMAGE_FORMAT_LEGACY:
853 hdr = (image_header_t *)addr;
855 bootstage_mark(BOOTSTAGE_ID_NAND_TYPE);
856 image_print_contents (hdr);
858 cnt = image_get_image_size (hdr);
860 #if defined(CONFIG_FIT)
861 case IMAGE_FORMAT_FIT:
862 fit_hdr = (const void *)addr;
863 puts ("Fit image detected...\n");
865 cnt = fit_get_size (fit_hdr);
869 bootstage_error(BOOTSTAGE_ID_NAND_TYPE);
870 puts ("** Unknown image type\n");
873 bootstage_mark(BOOTSTAGE_ID_NAND_TYPE);
875 r = nand_read_skip_bad(nand, offset, &cnt, (u_char *) addr);
877 puts("** Read error\n");
878 bootstage_error(BOOTSTAGE_ID_NAND_READ);
881 bootstage_mark(BOOTSTAGE_ID_NAND_READ);
883 #if defined(CONFIG_FIT)
884 /* This cannot be done earlier, we need complete FIT image in RAM first */
885 if (genimg_get_format ((void *)addr) == IMAGE_FORMAT_FIT) {
886 if (!fit_check_format (fit_hdr)) {
887 bootstage_error(BOOTSTAGE_ID_NAND_FIT_READ);
888 puts ("** Bad FIT image format\n");
891 bootstage_mark(BOOTSTAGE_ID_NAND_FIT_READ_OK);
892 fit_print_contents (fit_hdr);
896 /* Loading ok, update default load address */
900 return bootm_maybe_autostart(cmdtp, cmd);
903 int do_nandboot(cmd_tbl_t * cmdtp, int flag, int argc, char * const argv[])
905 char *boot_device = NULL;
907 ulong addr, offset = 0;
908 #if defined(CONFIG_CMD_MTDPARTS)
909 struct mtd_device *dev;
910 struct part_info *part;
914 char *p = (argc == 2) ? argv[1] : argv[2];
915 if (!(str2long(p, &addr)) && (mtdparts_init() == 0) &&
916 (find_dev_and_part(p, &dev, &pnum, &part) == 0)) {
917 if (dev->id->type != MTD_DEV_TYPE_NAND) {
918 puts("Not a NAND device\n");
924 addr = simple_strtoul(argv[1], NULL, 16);
926 addr = CONFIG_SYS_LOAD_ADDR;
927 return nand_load_image(cmdtp, &nand_info[dev->id->num],
928 part->offset, addr, argv[0]);
933 bootstage_mark(BOOTSTAGE_ID_NAND_PART);
936 addr = CONFIG_SYS_LOAD_ADDR;
937 boot_device = getenv("bootdevice");
940 addr = simple_strtoul(argv[1], NULL, 16);
941 boot_device = getenv("bootdevice");
944 addr = simple_strtoul(argv[1], NULL, 16);
945 boot_device = argv[2];
948 addr = simple_strtoul(argv[1], NULL, 16);
949 boot_device = argv[2];
950 offset = simple_strtoul(argv[3], NULL, 16);
953 #if defined(CONFIG_CMD_MTDPARTS)
956 bootstage_error(BOOTSTAGE_ID_NAND_SUFFIX);
957 return CMD_RET_USAGE;
959 bootstage_mark(BOOTSTAGE_ID_NAND_SUFFIX);
962 puts("\n** No boot device **\n");
963 bootstage_error(BOOTSTAGE_ID_NAND_BOOT_DEVICE);
966 bootstage_mark(BOOTSTAGE_ID_NAND_BOOT_DEVICE);
968 idx = simple_strtoul(boot_device, NULL, 16);
970 if (idx < 0 || idx >= CONFIG_SYS_MAX_NAND_DEVICE || !nand_info[idx].name) {
971 printf("\n** Device %d not available\n", idx);
972 bootstage_error(BOOTSTAGE_ID_NAND_AVAILABLE);
975 bootstage_mark(BOOTSTAGE_ID_NAND_AVAILABLE);
977 return nand_load_image(cmdtp, &nand_info[idx], offset, addr, argv[0]);
980 U_BOOT_CMD(nboot, 4, 1, do_nandboot,
981 "boot from NAND device",
982 "[partition] | [[[loadAddr] dev] offset]"