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  •  * drivers/mtd/nand/nand_util.c
    
     *
     * Copyright (C) 2006 by Weiss-Electronic GmbH.
     * All rights reserved.
     *
     * @author:	Guido Classen <clagix@gmail.com>
     * @descr:	NAND Flash support
     * @references: borrowed heavily from Linux mtd-utils code:
     *		flash_eraseall.c by Arcom Control System Ltd
     *		nandwrite.c by Steven J. Hill (sjhill@realitydiluted.com)
     *			       and Thomas Gleixner (tglx@linutronix.de)
     *
    
     * Copyright (C) 2008 Nokia Corporation: drop_ffs() function by
     * Artem Bityutskiy <dedekind1@gmail.com> from mtd-utils
     *
    
     * See file CREDITS for list of people who contributed to this
     * project.
     *
     * This program is free software; you can redistribute it and/or
     * modify it under the terms of the GNU General Public License version
     * 2 as published by the Free Software Foundation.
     *
     * This program is distributed in the hope that it will be useful,
     * but WITHOUT ANY WARRANTY; without even the implied warranty of
     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the
     * GNU General Public License for more details.
     *
     * You should have received a copy of the GNU General Public License
     * along with this program; if not, write to the Free Software
     * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
     * MA 02111-1307 USA
     *
    
     * Copyright 2010 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 <command.h>
    #include <watchdog.h>
    #include <malloc.h>
    
    #include <div64.h>
    
    #include <asm/errno.h>
    #include <linux/mtd/mtd.h>
    
    #include <nand.h>
    #include <jffs2/jffs2.h>
    
    
    typedef struct erase_info	erase_info_t;
    typedef struct mtd_info		mtd_info_t;
    
    
    /* support only for native endian JFFS2 */
    #define cpu_to_je16(x) (x)
    #define cpu_to_je32(x) (x)
    
    /**
     * nand_erase_opts: - erase NAND flash with support for various options
    
     *		      (jffs2 formatting)
    
     *
     * @param meminfo	NAND device to erase
     * @param opts		options,  @see struct nand_erase_options
     * @return		0 in case of success
     *
     * This code is ported from flash_eraseall.c from Linux mtd utils by
     * Arcom Control System Ltd.
     */
    int nand_erase_opts(nand_info_t *meminfo, const nand_erase_options_t *opts)
    {
    	struct jffs2_unknown_node cleanmarker;
    	erase_info_t erase;
    
    	unsigned long erase_length, erased_length; /* in blocks */
    
    	int bbtest = 1;
    	int result;
    	int percent_complete = -1;
    	const char *mtd_device = meminfo->name;
    
    	struct mtd_oob_ops oob_opts;
    	struct nand_chip *chip = meminfo->priv;
    
    	if ((opts->offset & (meminfo->erasesize - 1)) != 0) {
    		printf("Attempt to erase non block-aligned data\n");
    
    	memset(&erase, 0, sizeof(erase));
    
    	memset(&oob_opts, 0, sizeof(oob_opts));
    
    
    	erase.mtd = meminfo;
    	erase.len  = meminfo->erasesize;
    
    	erase.addr = opts->offset;
    
    	erase_length = lldiv(opts->length + meminfo->erasesize - 1,
    			     meminfo->erasesize);
    
    	cleanmarker.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
    	cleanmarker.nodetype = cpu_to_je16(JFFS2_NODETYPE_CLEANMARKER);
    
    	cleanmarker.totlen = cpu_to_je32(8);
    
    
    	/* scrub option allows to erase badblock. To prevent internal
    	 * check from erase() method, set block check method to dummy
    	 * and disable bad block table while erasing.
    	 */
    	if (opts->scrub) {
    
    		erase.scrub = opts->scrub;
    		/*
    		 * We don't need the bad block table anymore...
    
    		 * after scrub, there are no bad blocks left!
    		 */
    
    		if (chip->bbt) {
    			kfree(chip->bbt);
    
    		chip->bbt = NULL;
    
    	for (erased_length = 0;
    	     erased_length < erase_length;
    
    	     erase.addr += meminfo->erasesize) {
    
    		WATCHDOG_RESET();
    
    
    		if (!opts->scrub && bbtest) {
    			int ret = meminfo->block_isbad(meminfo, erase.addr);
    			if (ret > 0) {
    				if (!opts->quiet)
    					printf("\rSkipping bad block at  "
    
    					       "                         \n",
    					       erase.addr);
    
    
    				if (!opts->spread)
    					erased_length++;
    
    
    				continue;
    
    			} else if (ret < 0) {
    				printf("\n%s: MTD get bad block failed: %d\n",
    				       mtd_device,
    				       ret);
    				return -1;
    			}
    		}
    
    
    		result = meminfo->erase(meminfo, &erase);
    		if (result != 0) {
    			printf("\n%s: MTD Erase failure: %d\n",
    			       mtd_device, result);
    			continue;
    		}
    
    		/* format for JFFS2 ? */
    
    		if (opts->jffs2 && chip->ecc.layout->oobavail >= 8) {
    			chip->ops.ooblen = 8;
    
    			chip->ops.datbuf = NULL;
    
    			chip->ops.oobbuf = (uint8_t *)&cleanmarker;
    			chip->ops.ooboffs = 0;
    			chip->ops.mode = MTD_OOB_AUTO;
    
    			result = meminfo->write_oob(meminfo,
    
    			                            erase.addr,
    			                            &chip->ops);
    
    			if (result != 0) {
    				printf("\n%s: MTD writeoob failure: %d\n",
    
    				       mtd_device, result);
    
    			unsigned long long n = erased_length * 100ULL;
    
    			int percent;
    
    			do_div(n, erase_length);
    			percent = (int)n;
    
    
    			/* output progress message only at whole percent
    			 * steps to reduce the number of messages printed
    			 * on (slow) serial consoles
    			 */
    			if (percent != percent_complete) {
    				percent_complete = percent;
    
    
    				printf("\rErasing at 0x%llx -- %3d%% complete.",
    
    				       erase.addr, percent);
    
    
    				if (opts->jffs2 && result == 0)
    
    					printf(" Cleanmarker written at 0x%llx.",
    
    					       erase.addr);
    
    	if (opts->scrub)
    		chip->scan_bbt(meminfo);
    
    #ifdef CONFIG_CMD_NAND_LOCK_UNLOCK
    
    
    /******************************************************************************
     * Support for locking / unlocking operations of some NAND devices
     *****************************************************************************/
    
    /**
     * nand_lock: Set all pages of NAND flash chip to the LOCK or LOCK-TIGHT
     *	      state
     *
    
     * @param mtd		nand mtd instance
    
     * @param tight		bring device in lock tight mode
     *
     * @return		0 on success, -1 in case of error
     *
     * The lock / lock-tight command only applies to the whole chip. To get some
     * parts of the chip lock and others unlocked use the following sequence:
     *
     * - Lock all pages of the chip using nand_lock(mtd, 0) (or the lockpre pin)
     * - Call nand_unlock() once for each consecutive area to be unlocked
     * - If desired: Bring the chip to the lock-tight state using nand_lock(mtd, 1)
     *
     *   If the device is in lock-tight state software can't change the
     *   current active lock/unlock state of all pages. nand_lock() / nand_unlock()
     *   calls will fail. It is only posible to leave lock-tight state by
     *   an hardware signal (low pulse on _WP pin) or by power down.
     */
    
    int nand_lock(struct mtd_info *mtd, int tight)
    
    	struct nand_chip *chip = mtd->priv;
    
    
    	/* select the NAND device */
    
    	chip->select_chip(mtd, 0);
    
    	chip->cmdfunc(mtd,
    
    		      (tight ? NAND_CMD_LOCK_TIGHT : NAND_CMD_LOCK),
    		      -1, -1);
    
    	/* call wait ready function */
    
    	status = chip->waitfunc(mtd, chip);
    
    
    	/* see if device thinks it succeeded */
    	if (status & 0x01) {
    		ret = -1;
    	}
    
    	/* de-select the NAND device */
    
    	chip->select_chip(mtd, -1);
    
    	return ret;
    }
    
    /**
     * nand_get_lock_status: - query current lock state from one page of NAND
     *			   flash
     *
    
     * @param mtd		nand mtd instance
    
     * @param offset	page address to query (must be page-aligned!)
    
     *
     * @return		-1 in case of error
     *			>0 lock status:
     *			  bitfield with the following combinations:
     *			  NAND_LOCK_STATUS_TIGHT: page in tight state
     *			  NAND_LOCK_STATUS_UNLOCK: page unlocked
     *
     */
    
    int nand_get_lock_status(struct mtd_info *mtd, loff_t offset)
    
    {
    	int ret = 0;
    	int chipnr;
    	int page;
    
    	struct nand_chip *chip = mtd->priv;
    
    
    	/* select the NAND device */
    
    	chipnr = (int)(offset >> chip->chip_shift);
    	chip->select_chip(mtd, chipnr);
    
    	if ((offset & (mtd->writesize - 1)) != 0) {
    
    		printf("nand_get_lock_status: "
    
    			"Start address must be beginning of "
    			"nand page!\n");
    		ret = -1;
    		goto out;
    	}
    
    	/* check the Lock Status */
    
    	page = (int)(offset >> chip->page_shift);
    	chip->cmdfunc(mtd, NAND_CMD_LOCK_STATUS, -1, page & chip->pagemask);
    
    	ret = chip->read_byte(mtd) & (NAND_LOCK_STATUS_TIGHT
    
    					  | NAND_LOCK_STATUS_UNLOCK);
    
     out:
    	/* de-select the NAND device */
    
    	chip->select_chip(mtd, -1);
    
    	return ret;
    }
    
    /**
     * nand_unlock: - Unlock area of NAND pages
     *		  only one consecutive area can be unlocked at one time!
     *
    
     * @param mtd		nand mtd instance
    
     * @param start		start byte address
     * @param length	number of bytes to unlock (must be a multiple of
    
     *			page size nand->writesize)
    
     * @param allexcept	if set, unlock everything not selected
    
     *
     * @return		0 on success, -1 in case of error
     */
    
    int nand_unlock(struct mtd_info *mtd, loff_t start, size_t length,
    	int allexcept)
    
    {
    	int ret = 0;
    	int chipnr;
    	int status;
    	int page;
    
    	struct nand_chip *chip = mtd->priv;
    
    	debug("nand_unlock%s: start: %08llx, length: %d!\n",
    
    		allexcept ? " (allexcept)" : "", start, length);
    
    
    	/* select the NAND device */
    
    	chipnr = (int)(start >> chip->chip_shift);
    	chip->select_chip(mtd, chipnr);
    
    	chip->cmdfunc(mtd, NAND_CMD_STATUS, -1, -1);
    	if (!(chip->read_byte(mtd) & NAND_STATUS_WP)) {
    
    		printf("nand_unlock: Device is write protected!\n");
    
    	if ((start & (mtd->erasesize - 1)) != 0) {
    
    		printf("nand_unlock: Start address must be beginning of "
    
    			"nand block!\n");
    
    	if (length == 0 || (length & (mtd->erasesize - 1)) != 0) {
    
    		printf("nand_unlock: Length must be a multiple of nand block "
    
    			"size %08x!\n", mtd->erasesize);
    
    	/*
    	 * Set length so that the last address is set to the
    	 * starting address of the last block
    	 */
    	length -= mtd->erasesize;
    
    
    	/* submit address of first page to unlock */
    
    	page = (int)(start >> chip->page_shift);
    	chip->cmdfunc(mtd, NAND_CMD_UNLOCK1, -1, page & chip->pagemask);
    
    
    	/* submit ADDRESS of LAST page to unlock */
    
    	page += (int)(length >> chip->page_shift);
    
    
    	/*
    	 * Page addresses for unlocking are supposed to be block-aligned.
    	 * At least some NAND chips use the low bit to indicate that the
    	 * page range should be inverted.
    	 */
    	if (allexcept)
    		page |= 1;
    
    
    	chip->cmdfunc(mtd, NAND_CMD_UNLOCK2, -1, page & chip->pagemask);
    
    
    	/* call wait ready function */
    
    	status = chip->waitfunc(mtd, chip);
    
    	/* see if device thinks it succeeded */
    	if (status & 0x01) {
    		/* there was an error */
    		ret = -1;
    		goto out;
    	}
    
     out:
    	/* de-select the NAND device */
    
    	chip->select_chip(mtd, -1);
    
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    /**
    
     * check_skip_len
    
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     *
    
     * Check if there are any bad blocks, and whether length including bad
     * blocks fits into device
    
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     *
     * @param nand NAND device
     * @param offset offset in flash
     * @param length image length
    
     * @return 0 if the image fits and there are no bad blocks
     *         1 if the image fits, but there are bad blocks
     *        -1 if the image does not fit
    
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     */
    
    static int check_skip_len(nand_info_t *nand, loff_t offset, size_t length)
    
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    {
    	size_t len_excl_bad = 0;
    
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    	while (len_excl_bad < length) {
    
    		size_t block_len, block_off;
    		loff_t block_start;
    
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    		if (offset >= nand->size)
    			return -1;
    
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    		block_start = offset & ~(loff_t)(nand->erasesize - 1);
    		block_off = offset & (nand->erasesize - 1);
    		block_len = nand->erasesize - block_off;
    
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    		if (!nand_block_isbad(nand, block_start))
    			len_excl_bad += block_len;
    		else
    			ret = 1;
    
    		offset += block_len;
    
    #ifdef CONFIG_CMD_NAND_TRIMFFS
    static size_t drop_ffs(const nand_info_t *nand, const u_char *buf,
    			const size_t *len)
    {
    	size_t i, l = *len;
    
    	for (i = l - 1; i >= 0; i--)
    		if (buf[i] != 0xFF)
    			break;
    
    	/* The resulting length must be aligned to the minimum flash I/O size */
    	l = i + 1;
    	l = (l + nand->writesize - 1) / nand->writesize;
    	l *=  nand->writesize;
    
    	/*
    	 * since the input length may be unaligned, prevent access past the end
    	 * of the buffer
    	 */
    	return min(l, *len);
    }
    #endif
    
    
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    /**
     * nand_write_skip_bad:
     *
     * Write image to NAND flash.
     * Blocks that are marked bad are skipped and the is written to the next
     * block instead as long as the image is short enough to fit even after
     * skipping the bad blocks.
     *
     * @param nand  	NAND device
     * @param offset	offset in flash
     * @param length	buffer length
    
     * @param buffer        buffer to read from
    
     * @param flags		flags modifying the behaviour of the write to NAND
    
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     * @return		0 in case of success
     */
    
    int nand_write_skip_bad(nand_info_t *nand, loff_t offset, size_t *length,
    
    			u_char *buffer, int flags)
    
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    {
    
    	int rval = 0, blocksize;
    
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    	size_t left_to_write = *length;
    	u_char *p_buffer = buffer;
    
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    #ifdef CONFIG_CMD_NAND_YAFFS
    
    	if (flags & WITH_YAFFS_OOB) {
    
    		if (flags & ~WITH_YAFFS_OOB)
    			return -EINVAL;
    
    
    		int pages;
    		pages = nand->erasesize / nand->writesize;
    		blocksize = (pages * nand->oobsize) + nand->erasesize;
    		if (*length % (nand->writesize + nand->oobsize)) {
    
    			printf("Attempt to write incomplete page"
    
    				" in yaffs mode\n");
    			return -EINVAL;
    		}
    	} else
    #endif
    	{
    		blocksize = nand->erasesize;
    	}
    
    
    	/*
    	 * nand_write() handles unaligned, partial page writes.
    	 *
    	 * We allow length to be unaligned, for convenience in
    	 * using the $filesize variable.
    	 *
    	 * However, starting at an unaligned offset makes the
    	 * semantics of bad block skipping ambiguous (really,
    	 * you should only start a block skipping access at a
    	 * partition boundary).  So don't try to handle that.
    	 */
    	if ((offset & (nand->writesize - 1)) != 0) {
    
    		printf("Attempt to write non page-aligned data\n");
    
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    		return -EINVAL;
    	}
    
    
    	need_skip = check_skip_len(nand, offset, *length);
    	if (need_skip < 0) {
    
    		printf("Attempt to write outside the flash area\n");
    
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    		return -EINVAL;
    	}
    
    
    	if (!need_skip && !(flags & WITH_DROP_FFS)) {
    
    		rval = nand_write(nand, offset, length, buffer);
    
    		if (rval == 0)
    			return 0;
    
    		printf("NAND write to offset %llx failed %d\n",
    
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    	}
    
    	while (left_to_write > 0) {
    		size_t block_offset = offset & (nand->erasesize - 1);
    
    		size_t write_size, truncated_write_size;
    
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    		WATCHDOG_RESET();
    
    		if (nand_block_isbad(nand, offset & ~(nand->erasesize - 1))) {
    			printf("Skip bad block 0x%08llx\n",
    
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    				offset & ~(nand->erasesize - 1));
    			offset += nand->erasesize - block_offset;
    			continue;
    		}
    
    
    		if (left_to_write < (blocksize - block_offset))
    
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    			write_size = left_to_write;
    		else
    
    			write_size = blocksize - block_offset;
    
    #ifdef CONFIG_CMD_NAND_YAFFS
    
    		if (flags & WITH_YAFFS_OOB) {
    
    			int page, pages;
    			size_t pagesize = nand->writesize;
    			size_t pagesize_oob = pagesize + nand->oobsize;
    			struct mtd_oob_ops ops;
    
    			ops.len = pagesize;
    			ops.ooblen = nand->oobsize;
    			ops.mode = MTD_OOB_AUTO;
    			ops.ooboffs = 0;
    
    			pages = write_size / pagesize_oob;
    			for (page = 0; page < pages; page++) {
    
    				WATCHDOG_RESET();
    
    
    				ops.datbuf = p_buffer;
    				ops.oobbuf = ops.datbuf + pagesize;
    
    				rval = nand->write_oob(nand, offset, &ops);
    
    					break;
    
    				offset += pagesize;
    				p_buffer += pagesize_oob;
    			}
    		}
    		else
    #endif
    		{
    
    			truncated_write_size = write_size;
    #ifdef CONFIG_CMD_NAND_TRIMFFS
    			if (flags & WITH_DROP_FFS)
    				truncated_write_size = drop_ffs(nand, p_buffer,
    						&write_size);
    #endif
    
    			rval = nand_write(nand, offset, &truncated_write_size,
    					p_buffer);
    
    			offset += write_size;
    			p_buffer += write_size;
    		}
    
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    		if (rval != 0) {
    
    			printf("NAND write to offset %llx failed %d\n",
    
    				offset, rval);
    
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    			*length -= left_to_write;
    			return rval;
    		}
    
    		left_to_write -= write_size;
    	}
    
    	return 0;
    }
    
    /**
     * nand_read_skip_bad:
     *
     * Read image from NAND flash.
    
     * Blocks that are marked bad are skipped and the next block is read
    
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     * instead as long as the image is short enough to fit even after skipping the
     * bad blocks.
     *
     * @param nand NAND device
     * @param offset offset in flash
    
     * @param length buffer length, on return holds number of read bytes
    
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     * @param buffer buffer to write to
     * @return 0 in case of success
     */
    
    int nand_read_skip_bad(nand_info_t *nand, loff_t offset, size_t *length,
    
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    		       u_char *buffer)
    {
    	int rval;
    	size_t left_to_read = *length;
    	u_char *p_buffer = buffer;
    
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    	if ((offset & (nand->writesize - 1)) != 0) {
    
    		printf("Attempt to read non page-aligned data\n");
    
    		*length = 0;
    		return -EINVAL;
    	}
    
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    	need_skip = check_skip_len(nand, offset, *length);
    	if (need_skip < 0) {
    
    		printf("Attempt to read outside the flash area\n");
    
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    		return -EINVAL;
    	}
    
    
    	if (!need_skip) {
    
    		rval = nand_read(nand, offset, length, buffer);
    
    		if (!rval || rval == -EUCLEAN)
    			return 0;
    
    		printf("NAND read from offset %llx failed %d\n",
    
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    	}
    
    	while (left_to_read > 0) {
    		size_t block_offset = offset & (nand->erasesize - 1);
    		size_t read_length;
    
    
    		WATCHDOG_RESET();
    
    		if (nand_block_isbad(nand, offset & ~(nand->erasesize - 1))) {
    			printf("Skipping bad block 0x%08llx\n",
    
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    				offset & ~(nand->erasesize - 1));
    			offset += nand->erasesize - block_offset;
    			continue;
    		}
    
    		if (left_to_read < (nand->erasesize - block_offset))
    			read_length = left_to_read;
    		else
    			read_length = nand->erasesize - block_offset;
    
    
    		rval = nand_read(nand, offset, &read_length, p_buffer);
    
    		if (rval && rval != -EUCLEAN) {
    
    			printf("NAND read from offset %llx failed %d\n",
    
    				offset, rval);
    
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    			*length -= left_to_read;
    			return rval;
    		}
    
    		left_to_read -= read_length;
    		offset       += read_length;
    		p_buffer     += read_length;
    	}
    
    	return 0;
    }
    
    
    #ifdef CONFIG_CMD_NAND_TORTURE
    
    /**
     * check_pattern:
     *
     * Check if buffer contains only a certain byte pattern.
     *
     * @param buf buffer to check
     * @param patt the pattern to check
     * @param size buffer size in bytes
     * @return 1 if there are only patt bytes in buf
     *         0 if something else was found
     */
    static int check_pattern(const u_char *buf, u_char patt, int size)
    {
    	int i;
    
    	for (i = 0; i < size; i++)
    		if (buf[i] != patt)
    			return 0;
    	return 1;
    }
    
    /**
     * nand_torture:
     *
     * Torture a block of NAND flash.
     * This is useful to determine if a block that caused a write error is still
     * good or should be marked as bad.
     *
     * @param nand NAND device
     * @param offset offset in flash
     * @return 0 if the block is still good
     */
    int nand_torture(nand_info_t *nand, loff_t offset)
    {
    	u_char patterns[] = {0xa5, 0x5a, 0x00};
    	struct erase_info instr = {
    		.mtd = nand,
    		.addr = offset,
    		.len = nand->erasesize,
    	};
    	size_t retlen;
    	int err, ret = -1, i, patt_count;
    	u_char *buf;
    
    	if ((offset & (nand->erasesize - 1)) != 0) {
    		puts("Attempt to torture a block at a non block-aligned offset\n");
    		return -EINVAL;
    	}
    
    	if (offset + nand->erasesize > nand->size) {
    		puts("Attempt to torture a block outside the flash area\n");
    		return -EINVAL;
    	}
    
    	patt_count = ARRAY_SIZE(patterns);
    
    	buf = malloc(nand->erasesize);
    	if (buf == NULL) {
    		puts("Out of memory for erase block buffer\n");
    		return -ENOMEM;
    	}
    
    	for (i = 0; i < patt_count; i++) {
    		err = nand->erase(nand, &instr);
    		if (err) {
    			printf("%s: erase() failed for block at 0x%llx: %d\n",
    				nand->name, instr.addr, err);
    			goto out;
    		}
    
    		/* Make sure the block contains only 0xff bytes */
    		err = nand->read(nand, offset, nand->erasesize, &retlen, buf);
    		if ((err && err != -EUCLEAN) || retlen != nand->erasesize) {
    			printf("%s: read() failed for block at 0x%llx: %d\n",
    				nand->name, instr.addr, err);
    			goto out;
    		}
    
    		err = check_pattern(buf, 0xff, nand->erasesize);
    		if (!err) {
    			printf("Erased block at 0x%llx, but a non-0xff byte was found\n",
    				offset);
    			ret = -EIO;
    			goto out;
    		}
    
    		/* Write a pattern and check it */
    		memset(buf, patterns[i], nand->erasesize);
    		err = nand->write(nand, offset, nand->erasesize, &retlen, buf);
    		if (err || retlen != nand->erasesize) {
    			printf("%s: write() failed for block at 0x%llx: %d\n",
    				nand->name, instr.addr, err);
    			goto out;
    		}
    
    		err = nand->read(nand, offset, nand->erasesize, &retlen, buf);
    		if ((err && err != -EUCLEAN) || retlen != nand->erasesize) {
    			printf("%s: read() failed for block at 0x%llx: %d\n",
    				nand->name, instr.addr, err);
    			goto out;
    		}
    
    		err = check_pattern(buf, patterns[i], nand->erasesize);
    		if (!err) {
    			printf("Pattern 0x%.2x checking failed for block at "
    					"0x%llx\n", patterns[i], offset);
    			ret = -EIO;
    			goto out;
    		}
    	}
    
    	ret = 0;
    
    out:
    	free(buf);
    	return ret;
    }
    
    #endif