/*
   * Driver for NAND support, Rick Bronson
   * borrowed heavily from:
   * (c) 1999 Machine Vision Holdings, Inc.
   * (c) 1999, 2000 David Woodhouse <dwmw2@infradead.org>

   *

   * Ported 'dynenv' to 'nand env.oob' command
   * (C) 2010 Nanometrics, Inc.
   * 'dynenv' -- Dynamic environment offset in NAND OOB
   * (C) Copyright 2006-2007 OpenMoko, Inc.

   * Added 16-bit nand support
   * (C) 2004 Texas Instruments

   *

   * Copyright 2010, 2012 Freescale Semiconductor

   * The portions of this file whose copyright is held by Freescale and which
   * are not considered a derived work of GPL v2-only code may be distributed
   * and/or modified under the terms of the GNU General Public License as
   * published by the Free Software Foundation; either version 2 of the
   * License, or (at your option) any later version.

   */
  
  #include <common.h>

  #include <linux/mtd/mtd.h>

  #include <command.h>
  #include <watchdog.h>
  #include <malloc.h>
  #include <asm/byteorder.h>

  #include <jffs2/jffs2.h>
  #include <nand.h>

  #if defined(CONFIG_CMD_MTDPARTS)

  /* partition handling routines */

  int mtdparts_init(void);
  int id_parse(const char *id, const char **ret_id, u8 *dev_type, u8 *dev_num);
  int find_dev_and_part(const char *id, struct mtd_device **dev,

  		      u8 *part_num, struct part_info **part);

  #endif

  static int nand_dump(nand_info_t *nand, ulong off, int only_oob, int repeat)

  {
  	int i;

  	u_char *datbuf, *oobbuf, *p;

  	static loff_t last;

  	int ret = 0;

  
  	if (repeat)
  		off = last + nand->writesize;
  
  	last = off;

  	datbuf = memalign(ARCH_DMA_MINALIGN, nand->writesize);

  	if (!datbuf) {

  		puts("No memory for page buffer
  ");
  		return 1;
  	}

  
  	oobbuf = memalign(ARCH_DMA_MINALIGN, nand->oobsize);
  	if (!oobbuf) {
  		puts("No memory for page buffer
  ");
  		ret = 1;
  		goto free_dat;
  	}

  	off &= ~(nand->writesize - 1);

  	loff_t addr = (loff_t) off;

  	struct mtd_oob_ops ops;
  	memset(&ops, 0, sizeof(ops));
  	ops.datbuf = datbuf;

  	ops.oobbuf = oobbuf;

  	ops.len = nand->writesize;
  	ops.ooblen = nand->oobsize;

  	ops.mode = MTD_OPS_RAW;
  	i = mtd_read_oob(nand, addr, &ops);

  	if (i < 0) {

  		printf("Error (%d) reading page %08lx
  ", i, off);

  		ret = 1;
  		goto free_all;

  	}

  	printf("Page %08lx dump:
  ", off);

  	if (!only_oob) {
  		i = nand->writesize >> 4;
  		p = datbuf;
  
  		while (i--) {

  			printf("\t%02x %02x %02x %02x %02x %02x %02x %02x"
  			       "  %02x %02x %02x %02x %02x %02x %02x %02x
  ",
  			       p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7],

  			       p[8], p[9], p[10], p[11], p[12], p[13], p[14],
  			       p[15]);

  			p += 16;
  		}

  	}

  	puts("OOB:
  ");
  	i = nand->oobsize >> 3;

  	p = oobbuf;

  	while (i--) {

  		printf("\t%02x %02x %02x %02x %02x %02x %02x %02x
  ",
  		       p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7]);

  		p += 8;
  	}

  
  free_all:

  	free(oobbuf);

  free_dat:
  	free(datbuf);

  	return ret;

  }
  
  /* ------------------------------------------------------------------------- */

  static int set_dev(int dev)
  {
  	if (dev < 0 || dev >= CONFIG_SYS_MAX_NAND_DEVICE ||
  	    !nand_info[dev].name) {
  		puts("No such device
  ");
  		return -1;
  	}
  
  	if (nand_curr_device == dev)
  		return 0;
  
  	printf("Device %d: %s", dev, nand_info[dev].name);
  	puts("... is now current device
  ");
  	nand_curr_device = dev;
  
  #ifdef CONFIG_SYS_NAND_SELECT_DEVICE
  	board_nand_select_device(nand_info[dev].priv, dev);
  #endif
  
  	return 0;
  }

  #ifdef CONFIG_CMD_NAND_LOCK_UNLOCK
  static void print_status(ulong start, ulong end, ulong erasesize, int status)
  {

  	/*
  	 * Micron NAND flash (e.g. MT29F4G08ABADAH4) BLOCK LOCK READ STATUS is
  	 * not the same as others.  Instead of bit 1 being lock, it is
  	 * #lock_tight. To make the driver support either format, ignore bit 1
  	 * and use only bit 0 and bit 2.
  	 */

  	printf("%08lx - %08lx: %08lx blocks %s%s%s
  ",
  		start,
  		end - 1,
  		(end - start) / erasesize,
  		((status & NAND_LOCK_STATUS_TIGHT) ?  "TIGHT " : ""),

  		(!(status & NAND_LOCK_STATUS_UNLOCK) ?  "LOCK " : ""),

  		((status & NAND_LOCK_STATUS_UNLOCK) ?  "UNLOCK " : ""));
  }
  
  static void do_nand_status(nand_info_t *nand)
  {
  	ulong block_start = 0;
  	ulong off;
  	int last_status = -1;
  
  	struct nand_chip *nand_chip = nand->priv;
  	/* check the WP bit */
  	nand_chip->cmdfunc(nand, NAND_CMD_STATUS, -1, -1);
  	printf("device is %swrite protected
  ",
  		(nand_chip->read_byte(nand) & 0x80 ?
  		"NOT " : ""));
  
  	for (off = 0; off < nand->size; off += nand->erasesize) {
  		int s = nand_get_lock_status(nand, off);
  
  		/* print message only if status has changed */
  		if (s != last_status && off != 0) {
  			print_status(block_start, off, nand->erasesize,
  					last_status);
  			block_start = off;
  		}
  		last_status = s;
  	}
  	/* Print the last block info */
  	print_status(block_start, off, nand->erasesize, last_status);
  }
  #endif

  #ifdef CONFIG_ENV_OFFSET_OOB
  unsigned long nand_env_oob_offset;

  int do_nand_env_oob(cmd_tbl_t *cmdtp, int argc, char *const argv[])

  {
  	int ret;
  	uint32_t oob_buf[ENV_OFFSET_SIZE/sizeof(uint32_t)];

  	nand_info_t *nand = &nand_info[0];

  	char *cmd = argv[1];

  	if (CONFIG_SYS_MAX_NAND_DEVICE == 0 || !nand->name) {
  		puts("no devices available
  ");
  		return 1;
  	}
  
  	set_dev(0);

  	if (!strcmp(cmd, "get")) {
  		ret = get_nand_env_oob(nand, &nand_env_oob_offset);

  		if (ret)

  			return 1;

  
  		printf("0x%08lx
  ", nand_env_oob_offset);

  	} else if (!strcmp(cmd, "set")) {

  		loff_t addr;
  		loff_t maxsize;

  		struct mtd_oob_ops ops;

  		int idx = 0;

  
  		if (argc < 3)
  			goto usage;

  		/* We don't care about size, or maxsize. */

  		if (mtd_arg_off(argv[2], &idx, &addr, &maxsize, &maxsize,
  				MTD_DEV_TYPE_NAND, nand_info[idx].size)) {
  			puts("Offset or partition name expected
  ");
  			return 1;
  		}
  		if (set_dev(idx)) {

  			puts("Offset or partition name expected
  ");
  			return 1;
  		}
  
  		if (idx != 0) {
  			puts("Partition not on first NAND device
  ");

  			return 1;
  		}
  
  		if (nand->oobavail < ENV_OFFSET_SIZE) {

  			printf("Insufficient available OOB bytes:
  "
  			       "%d OOB bytes available but %d required for "
  			       "env.oob support
  ",
  			       nand->oobavail, ENV_OFFSET_SIZE);

  			return 1;
  		}
  
  		if ((addr & (nand->erasesize - 1)) != 0) {
  			printf("Environment offset must be block-aligned
  ");
  			return 1;
  		}
  
  		ops.datbuf = NULL;
  		ops.mode = MTD_OOB_AUTO;
  		ops.ooboffs = 0;
  		ops.ooblen = ENV_OFFSET_SIZE;
  		ops.oobbuf = (void *) oob_buf;
  
  		oob_buf[0] = ENV_OOB_MARKER;
  		oob_buf[1] = addr / nand->erasesize;
  
  		ret = nand->write_oob(nand, ENV_OFFSET_SIZE, &ops);

  		if (ret) {

  			printf("Error writing OOB block 0
  ");
  			return ret;
  		}

  
  		ret = get_nand_env_oob(nand, &nand_env_oob_offset);
  		if (ret) {
  			printf("Error reading env offset in OOB
  ");
  			return ret;
  		}
  
  		if (addr != nand_env_oob_offset) {
  			printf("Verification of env offset in OOB failed: "

  			       "0x%08llx expected but got 0x%08lx
  ",
  			       (unsigned long long)addr, nand_env_oob_offset);

  			return 1;
  		}

  	} else {
  		goto usage;
  	}
  
  	return ret;
  
  usage:

  	return CMD_RET_USAGE;

  }
  
  #endif

  static void nand_print_and_set_info(int idx)

  {
  	nand_info_t *nand = &nand_info[idx];
  	struct nand_chip *chip = nand->priv;

  	printf("Device %d: ", idx);
  	if (chip->numchips > 1)
  		printf("%dx ", chip->numchips);
  	printf("%s, sector size %u KiB
  ",
  	       nand->name, nand->erasesize >> 10);

  	printf("  Page size   %8d b
  ", nand->writesize);
  	printf("  OOB size    %8d b
  ", nand->oobsize);
  	printf("  Erase size  %8d b
  ", nand->erasesize);
  	printf("  subpagesize %8d b
  ", chip->subpagesize);
  	printf("  options     0x%8x
  ", chip->options);
  	printf("  bbt options 0x%8x
  ", chip->bbt_options);

  
  	/* Set geometry info */

  	setenv_hex("nand_writesize", nand->writesize);
  	setenv_hex("nand_oobsize", nand->oobsize);
  	setenv_hex("nand_erasesize", nand->erasesize);

  }

  static int raw_access(nand_info_t *nand, ulong addr, loff_t off, ulong count,
  			int read)
  {
  	int ret = 0;

  
  	while (count--) {
  		/* Raw access */
  		mtd_oob_ops_t ops = {
  			.datbuf = (u8 *)addr,
  			.oobbuf = ((u8 *)addr) + nand->writesize,
  			.len = nand->writesize,
  			.ooblen = nand->oobsize,

  			.mode = MTD_OPS_RAW

  		};

  		if (read) {

  			ret = mtd_read_oob(nand, off, &ops);

  		} else {

  			ret = mtd_write_oob(nand, off, &ops);

  			if (!ret)
  				ret = nand_verify_page_oob(nand, &ops, off);
  		}

  
  		if (ret) {
  			printf("%s: error at offset %llx, ret %d
  ",
  				__func__, (long long)off, ret);
  			break;
  		}
  
  		addr += nand->writesize + nand->oobsize;
  		off += nand->writesize;
  	}
  
  	return ret;
  }

  /* Adjust a chip/partition size down for bad blocks so we don't

   * read/write past the end of a chip/partition by accident.

   */
  static void adjust_size_for_badblocks(loff_t *size, loff_t offset, int dev)
  {
  	/* We grab the nand info object here fresh because this is usually
  	 * called after arg_off_size() which can change the value of dev.
  	 */
  	nand_info_t *nand = &nand_info[dev];
  	loff_t maxoffset = offset + *size;
  	int badblocks = 0;
  
  	/* count badblocks in NAND from offset to offset + size */
  	for (; offset < maxoffset; offset += nand->erasesize) {
  		if (nand_block_isbad(nand, offset))
  			badblocks++;
  	}
  	/* adjust size if any bad blocks found */
  	if (badblocks) {
  		*size -= badblocks * nand->erasesize;
  		printf("size adjusted to 0x%llx (%d bad blocks)
  ",
  		       (unsigned long long)*size, badblocks);
  	}
  }

  static int do_nand(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])

  {

  	int i, ret = 0;
  	ulong addr;

  	loff_t off, size, maxsize;

  	char *cmd, *s;
  	nand_info_t *nand;

  #ifdef CONFIG_SYS_NAND_QUIET
  	int quiet = CONFIG_SYS_NAND_QUIET;

  #else

  	int quiet = 0;

  #endif

  	const char *quiet_str = getenv("quiet");

  	int dev = nand_curr_device;

  	int repeat = flag & CMD_FLAG_REPEAT;

  
  	/* at least two arguments please */
  	if (argc < 2)
  		goto usage;

  	if (quiet_str)
  		quiet = simple_strtoul(quiet_str, NULL, 0) != 0;

  	cmd = argv[1];

  	/* Only "dump" is repeatable. */
  	if (repeat && strcmp(cmd, "dump"))
  		return 0;

  	if (strcmp(cmd, "info") == 0) {
  
  		putc('
  ');

  		for (i = 0; i < CONFIG_SYS_MAX_NAND_DEVICE; i++) {

  			if (nand_info[i].name)

  				nand_print_and_set_info(i);

  		}
  		return 0;
  	}
  
  	if (strcmp(cmd, "device") == 0) {

  		if (argc < 3) {

  			putc('
  ');

  			if (dev < 0 || dev >= CONFIG_SYS_MAX_NAND_DEVICE)

  				puts("no devices available
  ");

  			else

  				nand_print_and_set_info(dev);

  			return 0;
  		}

  		dev = (int)simple_strtoul(argv[2], NULL, 10);
  		set_dev(dev);

  		return 0;
  	}

  #ifdef CONFIG_ENV_OFFSET_OOB
  	/* this command operates only on the first nand device */

  	if (strcmp(cmd, "env.oob") == 0)
  		return do_nand_env_oob(cmdtp, argc - 1, argv + 1);

  #endif

  	/* The following commands operate on the current device, unless
  	 * overridden by a partition specifier.  Note that if somehow the
  	 * current device is invalid, it will have to be changed to a valid
  	 * one before these commands can run, even if a partition specifier
  	 * for another device is to be used.
  	 */
  	if (dev < 0 || dev >= CONFIG_SYS_MAX_NAND_DEVICE ||
  	    !nand_info[dev].name) {

  		puts("
  no devices available
  ");
  		return 1;
  	}

  	nand = &nand_info[dev];

  
  	if (strcmp(cmd, "bad") == 0) {

  		printf("
  Device %d bad blocks:
  ", dev);

  		for (off = 0; off < nand->size; off += nand->erasesize)
  			if (nand_block_isbad(nand, off))

  				printf("  %08llx
  ", (unsigned long long)off);

  		return 0;
  	}

  	/*
  	 * Syntax is:
  	 *   0    1     2       3    4
  	 *   nand erase [clean] [off size]
  	 */

  	if (strncmp(cmd, "erase", 5) == 0 || strncmp(cmd, "scrub", 5) == 0) {

  		nand_erase_options_t opts;

  		/* "clean" at index 2 means request to write cleanmarker */

  		int clean = argc > 2 && !strcmp("clean", argv[2]);

  		int scrub_yes = argc > 2 && !strcmp("-y", argv[2]);
  		int o = (clean || scrub_yes) ? 3 : 2;

  		int scrub = !strncmp(cmd, "scrub", 5);

  		int spread = 0;
  		int args = 2;

  		const char *scrub_warn =
  			"Warning: "
  			"scrub option will erase all factory set bad blocks!
  "
  			"         "
  			"There is no reliable way to recover them.
  "
  			"         "
  			"Use this command only for testing purposes if you
  "
  			"         "
  			"are sure of what you are doing!
  "
  			"
  Really scrub this NAND flash? <y/N>
  ";

  
  		if (cmd[5] != 0) {
  			if (!strcmp(&cmd[5], ".spread")) {
  				spread = 1;
  			} else if (!strcmp(&cmd[5], ".part")) {

  				args = 1;
  			} else if (!strcmp(&cmd[5], ".chip")) {

  				args = 0;
  			} else {
  				goto usage;
  			}
  		}
  
  		/*
  		 * Don't allow missing arguments to cause full chip/partition
  		 * erases -- easy to do accidentally, e.g. with a misspelled
  		 * variable name.
  		 */
  		if (argc != o + args)
  			goto usage;

  		printf("
  NAND %s: ", cmd);

  		/* skip first two or three arguments, look for offset and size */

  		if (mtd_arg_off_size(argc - o, argv + o, &dev, &off, &size,
  				     &maxsize, MTD_DEV_TYPE_NAND,
  				     nand_info[dev].size) != 0)
  			return 1;
  
  		if (set_dev(dev))

  			return 1;

  		nand = &nand_info[dev];

  		memset(&opts, 0, sizeof(opts));
  		opts.offset = off;
  		opts.length = size;
  		opts.jffs2  = clean;
  		opts.quiet  = quiet;

  		opts.spread = spread;

  
  		if (scrub) {

  			if (scrub_yes) {

  				opts.scrub = 1;

  			} else {
  				puts(scrub_warn);
  				if (confirm_yesno()) {

  					opts.scrub = 1;

  				} else {

  					puts("scrub aborted
  ");

  					return 1;

  				}

  			}
  		}
  		ret = nand_erase_opts(nand, &opts);

  		printf("%s
  ", ret ? "ERROR" : "OK");
  
  		return ret == 0 ? 0 : 1;
  	}
  
  	if (strncmp(cmd, "dump", 4) == 0) {
  		if (argc < 3)
  			goto usage;

  		off = (int)simple_strtoul(argv[2], NULL, 16);

  		ret = nand_dump(nand, off, !strcmp(&cmd[4], ".oob"), repeat);

  
  		return ret == 0 ? 1 : 0;

  	}

  	if (strncmp(cmd, "read", 4) == 0 || strncmp(cmd, "write", 5) == 0) {

  		size_t rwsize;

  		ulong pagecount = 1;

  		int read;

  		int raw = 0;

  		if (argc < 4)
  			goto usage;

  		addr = (ulong)simple_strtoul(argv[2], NULL, 16);

  		read = strncmp(cmd, "read", 4) == 0; /* 1 = read, 0 = write */

  		printf("
  NAND %s: ", read ? "read" : "write");

  		s = strchr(cmd, '.');

  		if (s && !strcmp(s, ".raw")) {

  			raw = 1;

  			if (mtd_arg_off(argv[3], &dev, &off, &size, &maxsize,
  					MTD_DEV_TYPE_NAND,
  					nand_info[dev].size))
  				return 1;
  
  			if (set_dev(dev))

  				return 1;

  			nand = &nand_info[dev];

  			if (argc > 4 && !str2long(argv[4], &pagecount)) {
  				printf("'%s' is not a number
  ", argv[4]);
  				return 1;
  			}
  
  			if (pagecount * nand->writesize > size) {
  				puts("Size exceeds partition or device limit
  ");
  				return -1;
  			}
  
  			rwsize = pagecount * (nand->writesize + nand->oobsize);
  		} else {

  			if (mtd_arg_off_size(argc - 3, argv + 3, &dev, &off,
  					     &size, &maxsize,
  					     MTD_DEV_TYPE_NAND,
  					     nand_info[dev].size) != 0)
  				return 1;
  
  			if (set_dev(dev))

  				return 1;

  			/* size is unspecified */
  			if (argc < 5)
  				adjust_size_for_badblocks(&size, off, dev);

  			rwsize = size;
  		}

  		nand = &nand_info[dev];

  		if (!s || !strcmp(s, ".jffs2") ||
  		    !strcmp(s, ".e") || !strcmp(s, ".i")) {

  			if (read)

  				ret = nand_read_skip_bad(nand, off, &rwsize,

  							 NULL, maxsize,

  							 (u_char *)addr);

  			else

  				ret = nand_write_skip_bad(nand, off, &rwsize,

  							  NULL, maxsize,

  							  (u_char *)addr,
  							  WITH_WR_VERIFY);

  #ifdef CONFIG_CMD_NAND_TRIMFFS
  		} else if (!strcmp(s, ".trimffs")) {
  			if (read) {
  				printf("Unknown nand command suffix '%s'
  ", s);
  				return 1;
  			}

  			ret = nand_write_skip_bad(nand, off, &rwsize, NULL,
  						maxsize, (u_char *)addr,

  						WITH_DROP_FFS | WITH_WR_VERIFY);

  #endif

  		} else if (!strcmp(s, ".oob")) {

  			/* out-of-band data */
  			mtd_oob_ops_t ops = {
  				.oobbuf = (u8 *)addr,

  				.ooblen = rwsize,

  				.mode = MTD_OPS_RAW

  			};

  			if (read)

  				ret = mtd_read_oob(nand, off, &ops);

  			else

  				ret = mtd_write_oob(nand, off, &ops);

  		} else if (raw) {
  			ret = raw_access(nand, addr, off, pagecount, read);

  		} else {

  			printf("Unknown nand command suffix '%s'.
  ", s);
  			return 1;

  		}

  		printf(" %zu bytes %s: %s
  ", rwsize,

  		       read ? "read" : "written", ret ? "ERROR" : "OK");

  
  		return ret == 0 ? 0 : 1;
  	}

  #ifdef CONFIG_CMD_NAND_TORTURE
  	if (strcmp(cmd, "torture") == 0) {
  		if (argc < 3)
  			goto usage;
  
  		if (!str2off(argv[2], &off)) {
  			puts("Offset is not a valid number
  ");
  			return 1;
  		}
  
  		printf("
  NAND torture: device %d offset 0x%llx size 0x%x
  ",
  			dev, off, nand->erasesize);
  		ret = nand_torture(nand, off);
  		printf(" %s
  ", ret ? "Failed" : "Passed");
  
  		return ret == 0 ? 0 : 1;
  	}
  #endif

  	if (strcmp(cmd, "markbad") == 0) {

  		argc -= 2;
  		argv += 2;

  		if (argc <= 0)
  			goto usage;
  
  		while (argc > 0) {
  			addr = simple_strtoul(*argv, NULL, 16);

  			if (mtd_block_markbad(nand, addr)) {

  				printf("block 0x%08lx NOT marked "
  					"as bad! ERROR %d
  ",
  					addr, ret);
  				ret = 1;
  			} else {
  				printf("block 0x%08lx successfully "
  					"marked as bad
  ",
  					addr);
  			}
  			--argc;
  			++argv;

  		}

  		return ret;

  	}

  	if (strcmp(cmd, "biterr") == 0) {
  		/* todo */
  		return 1;
  	}

  #ifdef CONFIG_CMD_NAND_LOCK_UNLOCK

  	if (strcmp(cmd, "lock") == 0) {

  		int tight = 0;

  		int status = 0;
  		if (argc == 3) {
  			if (!strcmp("tight", argv[2]))
  				tight = 1;
  			if (!strcmp("status", argv[2]))
  				status = 1;
  		}

  		if (status) {

  			do_nand_status(nand);

  		} else {

  			if (!nand_lock(nand, tight)) {
  				puts("NAND flash successfully locked
  ");
  			} else {
  				puts("Error locking NAND flash
  ");
  				return 1;
  			}

  		}
  		return 0;
  	}

  	if (strncmp(cmd, "unlock", 5) == 0) {
  		int allexcept = 0;
  
  		s = strchr(cmd, '.');
  
  		if (s && !strcmp(s, ".allexcept"))
  			allexcept = 1;

  		if (mtd_arg_off_size(argc - 2, argv + 2, &dev, &off, &size,
  				     &maxsize, MTD_DEV_TYPE_NAND,
  				     nand_info[dev].size) < 0)
  			return 1;
  
  		if (set_dev(dev))

  			return 1;

  		if (!nand_unlock(&nand_info[dev], off, size, allexcept)) {

  			puts("NAND flash successfully unlocked
  ");
  		} else {
  			puts("Error unlocking NAND flash, "

  			     "write and erase will probably fail
  ");

  			return 1;
  		}

  		return 0;
  	}

  #endif

  usage:

  	return CMD_RET_USAGE;

  }

  #ifdef CONFIG_SYS_LONGHELP
  static char nand_help_text[] =

  	"info - show available NAND devices
  "
  	"nand device [dev] - show or set current device
  "
  	"nand read - addr off|partition size
  "
  	"nand write - addr off|partition size
  "
  	"    read/write 'size' bytes starting at offset 'off'
  "
  	"    to/from memory address 'addr', skipping bad blocks.
  "

  	"nand read.raw - addr off|partition [count]
  "
  	"nand write.raw - addr off|partition [count]
  "
  	"    Use read.raw/write.raw to avoid ECC and access the flash as-is.
  "

  #ifdef CONFIG_CMD_NAND_TRIMFFS
  	"nand write.trimffs - addr off|partition size
  "
  	"    write 'size' bytes starting at offset 'off' from memory address
  "
  	"    'addr', skipping bad blocks and dropping any pages at the end
  "
  	"    of eraseblocks that contain only 0xFF
  "
  #endif

  	"nand erase[.spread] [clean] off size - erase 'size' bytes "

  	"from offset 'off'
  "
  	"    With '.spread', erase enough for given file size, otherwise,
  "
  	"    'size' includes skipped bad blocks.
  "
  	"nand erase.part [clean] partition - erase entire mtd partition'
  "
  	"nand erase.chip [clean] - erase entire chip'
  "

  	"nand bad - show bad blocks
  "
  	"nand dump[.oob] off - dump page
  "

  #ifdef CONFIG_CMD_NAND_TORTURE
  	"nand torture off - torture block at offset
  "
  #endif

  	"nand scrub [-y] off size | scrub.part partition | scrub.chip
  "

  	"    really clean NAND erasing bad blocks (UNSAFE)
  "

  	"nand markbad off [...] - mark bad block(s) at offset (UNSAFE)
  "
  	"nand biterr off - make a bit error at offset (UNSAFE)"

  #ifdef CONFIG_CMD_NAND_LOCK_UNLOCK

  	"
  "
  	"nand lock [tight] [status]
  "
  	"    bring nand to lock state or display locked pages
  "

  	"nand unlock[.allexcept] [offset] [size] - unlock section"

  #endif

  #ifdef CONFIG_ENV_OFFSET_OOB
  	"
  "
  	"nand env.oob - environment offset in OOB of block 0 of"
  	"    first device.
  "
  	"nand env.oob set off|partition - set enviromnent offset
  "
  	"nand env.oob get - get environment offset"
  #endif

  	"";
  #endif
  
  U_BOOT_CMD(
  	nand, CONFIG_SYS_MAXARGS, 1, do_nand,
  	"NAND sub-system", nand_help_text

  );

  static int nand_load_image(cmd_tbl_t *cmdtp, nand_info_t *nand,

  			   ulong offset, ulong addr, char *cmd)

  {

  	int r;

  	char *s;

  	size_t cnt;

  #if defined(CONFIG_IMAGE_FORMAT_LEGACY)

  	image_header_t *hdr;

  #endif

  #if defined(CONFIG_FIT)

  	const void *fit_hdr = NULL;

  #endif

  
  	s = strchr(cmd, '.');
  	if (s != NULL &&

  	    (strcmp(s, ".jffs2") && strcmp(s, ".e") && strcmp(s, ".i"))) {

  		printf("Unknown nand load suffix '%s'
  ", s);

  		bootstage_error(BOOTSTAGE_ID_NAND_SUFFIX);

  		return 1;
  	}

  	printf("
  Loading from %s, offset 0x%lx
  ", nand->name, offset);

  	cnt = nand->writesize;

  	r = nand_read_skip_bad(nand, offset, &cnt, NULL, nand->size,
  			(u_char *)addr);

  	if (r) {

  		puts("** Read error
  ");

  		bootstage_error(BOOTSTAGE_ID_NAND_HDR_READ);

  		return 1;
  	}

  	bootstage_mark(BOOTSTAGE_ID_NAND_HDR_READ);

  	switch (genimg_get_format ((void *)addr)) {

  #if defined(CONFIG_IMAGE_FORMAT_LEGACY)

  	case IMAGE_FORMAT_LEGACY:
  		hdr = (image_header_t *)addr;

  		bootstage_mark(BOOTSTAGE_ID_NAND_TYPE);

  		image_print_contents (hdr);

  		cnt = image_get_image_size (hdr);
  		break;

  #endif

  #if defined(CONFIG_FIT)
  	case IMAGE_FORMAT_FIT:

  		fit_hdr = (const void *)addr;

  		puts ("Fit image detected...
  ");
  
  		cnt = fit_get_size (fit_hdr);
  		break;

  #endif
  	default:

  		bootstage_error(BOOTSTAGE_ID_NAND_TYPE);

  		puts ("** Unknown image type
  ");

  		return 1;
  	}

  	bootstage_mark(BOOTSTAGE_ID_NAND_TYPE);

  	r = nand_read_skip_bad(nand, offset, &cnt, NULL, nand->size,
  			(u_char *)addr);

  	if (r) {

  		puts("** Read error
  ");

  		bootstage_error(BOOTSTAGE_ID_NAND_READ);

  		return 1;
  	}

  	bootstage_mark(BOOTSTAGE_ID_NAND_READ);

  #if defined(CONFIG_FIT)
  	/* This cannot be done earlier, we need complete FIT image in RAM first */

  	if (genimg_get_format ((void *)addr) == IMAGE_FORMAT_FIT) {
  		if (!fit_check_format (fit_hdr)) {

  			bootstage_error(BOOTSTAGE_ID_NAND_FIT_READ);

  			puts ("** Bad FIT image format
  ");
  			return 1;
  		}

  		bootstage_mark(BOOTSTAGE_ID_NAND_FIT_READ_OK);

  		fit_print_contents (fit_hdr);
  	}

  #endif

  	/* Loading ok, update default load address */
  
  	load_addr = addr;

  	return bootm_maybe_autostart(cmdtp, cmd);

  }

  static int do_nandboot(cmd_tbl_t *cmdtp, int flag, int argc,
  		       char * const argv[])

  {
  	char *boot_device = NULL;
  	int idx;
  	ulong addr, offset = 0;

  #if defined(CONFIG_CMD_MTDPARTS)

  	struct mtd_device *dev;
  	struct part_info *part;
  	u8 pnum;
  
  	if (argc >= 2) {
  		char *p = (argc == 2) ? argv[1] : argv[2];
  		if (!(str2long(p, &addr)) && (mtdparts_init() == 0) &&
  		    (find_dev_and_part(p, &dev, &pnum, &part) == 0)) {
  			if (dev->id->type != MTD_DEV_TYPE_NAND) {
  				puts("Not a NAND device
  ");
  				return 1;
  			}
  			if (argc > 3)
  				goto usage;
  			if (argc == 3)

  				addr = simple_strtoul(argv[1], NULL, 16);

  			else

  				addr = CONFIG_SYS_LOAD_ADDR;

  			return nand_load_image(cmdtp, &nand_info[dev->id->num],

  					       part->offset, addr, argv[0]);

  		}
  	}
  #endif

  	bootstage_mark(BOOTSTAGE_ID_NAND_PART);

  	switch (argc) {
  	case 1:

  		addr = CONFIG_SYS_LOAD_ADDR;

  		boot_device = getenv("bootdevice");
  		break;
  	case 2:
  		addr = simple_strtoul(argv[1], NULL, 16);
  		boot_device = getenv("bootdevice");
  		break;
  	case 3:
  		addr = simple_strtoul(argv[1], NULL, 16);
  		boot_device = argv[2];
  		break;
  	case 4:
  		addr = simple_strtoul(argv[1], NULL, 16);
  		boot_device = argv[2];
  		offset = simple_strtoul(argv[3], NULL, 16);
  		break;
  	default:

  #if defined(CONFIG_CMD_MTDPARTS)

  usage:
  #endif

  		bootstage_error(BOOTSTAGE_ID_NAND_SUFFIX);

  		return CMD_RET_USAGE;

  	}

  	bootstage_mark(BOOTSTAGE_ID_NAND_SUFFIX);

  
  	if (!boot_device) {
  		puts("
  ** No boot device **
  ");

  		bootstage_error(BOOTSTAGE_ID_NAND_BOOT_DEVICE);

  		return 1;
  	}

  	bootstage_mark(BOOTSTAGE_ID_NAND_BOOT_DEVICE);

  	idx = simple_strtoul(boot_device, NULL, 16);

  	if (idx < 0 || idx >= CONFIG_SYS_MAX_NAND_DEVICE || !nand_info[idx].name) {

  		printf("
  ** Device %d not available
  ", idx);

  		bootstage_error(BOOTSTAGE_ID_NAND_AVAILABLE);

  		return 1;
  	}

  	bootstage_mark(BOOTSTAGE_ID_NAND_AVAILABLE);

  
  	return nand_load_image(cmdtp, &nand_info[idx], offset, addr, argv[0]);
  }
  
  U_BOOT_CMD(nboot, 4, 1, do_nandboot,

  	"boot from NAND device",

  	"[partition] | [[[loadAddr] dev] offset]"
  );