[J-u-boot.git] / drivers / mtd / onenand / onenand_bbt.c

/*
 *  linux/drivers/mtd/onenand/onenand_bbt.c
 *
 *  Bad Block Table support for the OneNAND driver
 *
 *  Copyright(c) 2005-2008 Samsung Electronics
 *  Kyungmin Park <[email protected]>
 *
 *  TODO:
 *    Split BBT core and chip specific BBT.
 *
 * 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.
 */

#include <common.h>
#include <linux/mtd/compat.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/onenand.h>
#include <malloc.h>

#include <asm/errno.h>

/**
 * check_short_pattern - [GENERIC] check if a pattern is in the buffer
 * @param buf		the buffer to search
 * @param len		the length of buffer to search
 * @param paglen	the pagelength
 * @param td		search pattern descriptor
 *
 * Check for a pattern at the given place. Used to search bad block
 * tables and good / bad block identifiers. Same as check_pattern, but
 * no optional empty check and the pattern is expected to start
 * at offset 0.
 */
static int check_short_pattern(uint8_t * buf, int len, int paglen,
			       struct nand_bbt_descr *td)
{
	int i;
	uint8_t *p = buf;

	/* Compare the pattern */
	for (i = 0; i < td->len; i++) {
		if (p[i] != td->pattern[i])
			return -1;
	}
	return 0;
}

/**
 * create_bbt - [GENERIC] Create a bad block table by scanning the device
 * @param mtd		MTD device structure
 * @param buf		temporary buffer
 * @param bd		descriptor for the good/bad block search pattern
 * @param chip		create the table for a specific chip, -1 read all chips.
 *              Applies only if NAND_BBT_PERCHIP option is set
 *
 * Create a bad block table by scanning the device
 * for the given good/bad block identify pattern
 */
static int create_bbt(struct mtd_info *mtd, uint8_t * buf,
		      struct nand_bbt_descr *bd, int chip)
{
	struct onenand_chip *this = mtd->priv;
	struct bbm_info *bbm = this->bbm;
	int i, j, numblocks, len, scanlen;
	int startblock;
	loff_t from;
	size_t readlen, ooblen;
	struct mtd_oob_ops ops;

	printk(KERN_INFO "Scanning device for bad blocks\n");

	len = 1;

	/* We need only read few bytes from the OOB area */
	scanlen = ooblen = 0;
	readlen = bd->len;

	/* chip == -1 case only */
	/* Note that numblocks is 2 * (real numblocks) here;
	 * see i += 2 below as it makses shifting and masking less painful
	 */
	numblocks = mtd->size >> (bbm->bbt_erase_shift - 1);
	startblock = 0;
	from = 0;

	ops.mode = MTD_OOB_PLACE;
	ops.ooblen = readlen;
	ops.oobbuf = buf;
	ops.len = ops.ooboffs = ops.retlen = ops.oobretlen = 0;

	for (i = startblock; i < numblocks;) {
		int ret;

		for (j = 0; j < len; j++) {
			/* No need to read pages fully,
			 * just read required OOB bytes */
			ret = onenand_bbt_read_oob(mtd,
					     from + j * mtd->writesize +
					     bd->offs, &ops);

			/* If it is a initial bad block, just ignore it */
			if (ret == ONENAND_BBT_READ_FATAL_ERROR)
				return -EIO;

			if (ret || check_short_pattern
			    (&buf[j * scanlen], scanlen, mtd->writesize, bd)) {
				bbm->bbt[i >> 3] |= 0x03 << (i & 0x6);
				printk(KERN_WARNING
				       "Bad eraseblock %d at 0x%08x\n", i >> 1,
				       (unsigned int)from);
				break;
			}
		}
		i += 2;
		from += (1 << bbm->bbt_erase_shift);
	}

	return 0;
}

/**
 * onenand_memory_bbt - [GENERIC] create a memory based bad block table
 * @param mtd		MTD device structure
 * @param bd		descriptor for the good/bad block search pattern
 *
 * The function creates a memory based bbt by scanning the device
 * for manufacturer / software marked good / bad blocks
 */
static inline int onenand_memory_bbt(struct mtd_info *mtd,
				     struct nand_bbt_descr *bd)
{
	unsigned char data_buf[MAX_ONENAND_PAGESIZE];

	bd->options &= ~NAND_BBT_SCANEMPTY;
	return create_bbt(mtd, data_buf, bd, -1);
}

/**
 * onenand_isbad_bbt - [OneNAND Interface] Check if a block is bad
 * @param mtd		MTD device structure
 * @param offs		offset in the device
 * @param allowbbt	allow access to bad block table region
 */
static int onenand_isbad_bbt(struct mtd_info *mtd, loff_t offs, int allowbbt)
{
	struct onenand_chip *this = mtd->priv;
	struct bbm_info *bbm = this->bbm;
	int block;
	uint8_t res;

	/* Get block number * 2 */
	block = (int)(offs >> (bbm->bbt_erase_shift - 1));
	res = (bbm->bbt[block >> 3] >> (block & 0x06)) & 0x03;

	MTDDEBUG (MTD_DEBUG_LEVEL2,
		"onenand_isbad_bbt: bbt info for offs 0x%08x: (block %d) 0x%02x\n",
		(unsigned int)offs, block >> 1, res);

	switch ((int)res) {
	case 0x00:
		return 0;
	case 0x01:
		return 1;
	case 0x02:
		return allowbbt ? 0 : 1;
	}

	return 1;
}

/**
 * onenand_scan_bbt - [OneNAND Interface] scan, find, read and maybe create bad block table(s)
 * @param mtd		MTD device structure
 * @param bd		descriptor for the good/bad block search pattern
 *
 * The function checks, if a bad block table(s) is/are already
 * available. If not it scans the device for manufacturer
 * marked good / bad blocks and writes the bad block table(s) to
 * the selected place.
 *
 * The bad block table memory is allocated here. It must be freed
 * by calling the onenand_free_bbt function.
 *
 */
int onenand_scan_bbt(struct mtd_info *mtd, struct nand_bbt_descr *bd)
{
	struct onenand_chip *this = mtd->priv;
	struct bbm_info *bbm = this->bbm;
	int len, ret = 0;

	len = mtd->size >> (this->erase_shift + 2);
	/* Allocate memory (2bit per block) */
	bbm->bbt = malloc(len);
	if (!bbm->bbt) {
		printk(KERN_ERR "onenand_scan_bbt: Out of memory\n");
		return -ENOMEM;
	}
	/* Clear the memory bad block table */
	memset(bbm->bbt, 0x00, len);

	/* Set the bad block position */
	bbm->badblockpos = ONENAND_BADBLOCK_POS;

	/* Set erase shift */
	bbm->bbt_erase_shift = this->erase_shift;

	if (!bbm->isbad_bbt)
		bbm->isbad_bbt = onenand_isbad_bbt;

	/* Scan the device to build a memory based bad block table */
	if ((ret = onenand_memory_bbt(mtd, bd))) {
		printk(KERN_ERR
		       "onenand_scan_bbt: Can't scan flash and build the RAM-based BBT\n");
		free(bbm->bbt);
		bbm->bbt = NULL;
	}

	return ret;
}

/*
 * Define some generic bad / good block scan pattern which are used
 * while scanning a device for factory marked good / bad blocks.
 */
static uint8_t scan_ff_pattern[] = { 0xff, 0xff };

static struct nand_bbt_descr largepage_memorybased = {
	.options = 0,
	.offs = 0,
	.len = 2,
	.pattern = scan_ff_pattern,
};

/**
 * onenand_default_bbt - [OneNAND Interface] Select a default bad block table for the device
 * @param mtd		MTD device structure
 *
 * This function selects the default bad block table
 * support for the device and calls the onenand_scan_bbt function
 */
int onenand_default_bbt(struct mtd_info *mtd)
{
	struct onenand_chip *this = mtd->priv;
	struct bbm_info *bbm;

	this->bbm = malloc(sizeof(struct bbm_info));
	if (!this->bbm)
		return -ENOMEM;

	bbm = this->bbm;

	memset(bbm, 0, sizeof(struct bbm_info));

	/* 1KB page has same configuration as 2KB page */
	if (!bbm->badblock_pattern)
		bbm->badblock_pattern = &largepage_memorybased;

	return onenand_scan_bbt(mtd, bbm->badblock_pattern);
}
Commit	Line	Data
17aa2800 KP	1	/*
	2	* linux/drivers/mtd/onenand/onenand_bbt.c
	3	*
	4	* Bad Block Table support for the OneNAND driver
	5	*
ef0921d6	6	* Copyright(c) 2005-2008 Samsung Electronics
17aa2800 KP	7	* Kyungmin Park <[email protected]>
	8	*
	9	* TODO:
	10	* Split BBT core and chip specific BBT.
	11	*
	12	* This program is free software; you can redistribute it and/or modify
	13	* it under the terms of the GNU General Public License version 2 as
	14	* published by the Free Software Foundation.
	15	*/
	16
	17	#include <common.h>
17aa2800 KP	18	#include <linux/mtd/compat.h>
	19	#include <linux/mtd/mtd.h>
	20	#include <linux/mtd/onenand.h>
	21	#include <malloc.h>
	22
	23	#include <asm/errno.h>
	24
	25	/**
	26	* check_short_pattern - [GENERIC] check if a pattern is in the buffer
	27	* @param buf the buffer to search
	28	* @param len the length of buffer to search
	29	* @param paglen the pagelength
	30	* @param td search pattern descriptor
	31	*
	32	* Check for a pattern at the given place. Used to search bad block
	33	* tables and good / bad block identifiers. Same as check_pattern, but
	34	* no optional empty check and the pattern is expected to start
	35	* at offset 0.
	36	*/
	37	static int check_short_pattern(uint8_t * buf, int len, int paglen,
	38	struct nand_bbt_descr *td)
	39	{
	40	int i;
	41	uint8_t *p = buf;
	42
	43	/* Compare the pattern */
	44	for (i = 0; i < td->len; i++) {
	45	if (p[i] != td->pattern[i])
	46	return -1;
	47	}
	48	return 0;
	49	}
	50
	51	/**
	52	* create_bbt - [GENERIC] Create a bad block table by scanning the device
	53	* @param mtd MTD device structure
	54	* @param buf temporary buffer
	55	* @param bd descriptor for the good/bad block search pattern
	56	* @param chip create the table for a specific chip, -1 read all chips.
ef0921d6	57	* Applies only if NAND_BBT_PERCHIP option is set
17aa2800 KP	58	*
	59	* Create a bad block table by scanning the device
	60	* for the given good/bad block identify pattern
	61	*/
	62	static int create_bbt(struct mtd_info mtd, uint8_t buf,
	63	struct nand_bbt_descr *bd, int chip)
	64	{
	65	struct onenand_chip *this = mtd->priv;
	66	struct bbm_info *bbm = this->bbm;
	67	int i, j, numblocks, len, scanlen;
	68	int startblock;
	69	loff_t from;
	70	size_t readlen, ooblen;
bfd7f386	71	struct mtd_oob_ops ops;
17aa2800 KP	72
	73	printk(KERN_INFO "Scanning device for bad blocks\n");
	74
	75	len = 1;
	76
	77	/* We need only read few bytes from the OOB area */
	78	scanlen = ooblen = 0;
	79	readlen = bd->len;
	80
	81	/* chip == -1 case only */
	82	/* Note that numblocks is 2 * (real numblocks) here;
	83	* see i += 2 below as it makses shifting and masking less painful
	84	*/
	85	numblocks = mtd->size >> (bbm->bbt_erase_shift - 1);
	86	startblock = 0;
	87	from = 0;
	88
bfd7f386 KP	89	ops.mode = MTD_OOB_PLACE;
	90	ops.ooblen = readlen;
	91	ops.oobbuf = buf;
	92	ops.len = ops.ooboffs = ops.retlen = ops.oobretlen = 0;
	93
17aa2800 KP	94	for (i = startblock; i < numblocks;) {
	95	int ret;
	96
	97	for (j = 0; j < len; j++) {
17aa2800 KP	98	/* No need to read pages fully,
17aa2800 KP	99	* just read required OOB bytes */
bfd7f386	100	ret = onenand_bbt_read_oob(mtd,
d438d508	101	from + j * mtd->writesize +
bfd7f386	102	bd->offs, &ops);
17aa2800	103
bfd7f386	104	/* If it is a initial bad block, just ignore it */
a49d10cf WD	105	if (ret == ONENAND_BBT_READ_FATAL_ERROR)
a49d10cf WD	106	return -EIO;
17aa2800	107
bfd7f386	108	if (ret \|\| check_short_pattern
d438d508	109	(&buf[j * scanlen], scanlen, mtd->writesize, bd)) {
17aa2800 KP	110	bbm->bbt[i >> 3] \|= 0x03 << (i & 0x6);
	111	printk(KERN_WARNING
	112	"Bad eraseblock %d at 0x%08x\n", i >> 1,
	113	(unsigned int)from);
	114	break;
	115	}
	116	}
	117	i += 2;
	118	from += (1 << bbm->bbt_erase_shift);
	119	}
	120
	121	return 0;
	122	}
	123
	124	/**
	125	* onenand_memory_bbt - [GENERIC] create a memory based bad block table
	126	* @param mtd MTD device structure
	127	* @param bd descriptor for the good/bad block search pattern
	128	*
	129	* The function creates a memory based bbt by scanning the device
	130	* for manufacturer / software marked good / bad blocks
	131	*/
	132	static inline int onenand_memory_bbt(struct mtd_info *mtd,
	133	struct nand_bbt_descr *bd)
	134	{
	135	unsigned char data_buf[MAX_ONENAND_PAGESIZE];
	136
	137	bd->options &= ~NAND_BBT_SCANEMPTY;
	138	return create_bbt(mtd, data_buf, bd, -1);
	139	}
	140
	141	/**
	142	* onenand_isbad_bbt - [OneNAND Interface] Check if a block is bad
	143	* @param mtd MTD device structure
	144	* @param offs offset in the device
	145	* @param allowbbt allow access to bad block table region
	146	*/
	147	static int onenand_isbad_bbt(struct mtd_info *mtd, loff_t offs, int allowbbt)
	148	{
	149	struct onenand_chip *this = mtd->priv;
	150	struct bbm_info *bbm = this->bbm;
	151	int block;
	152	uint8_t res;
	153
	154	/* Get block number * 2 */
	155	block = (int)(offs >> (bbm->bbt_erase_shift - 1));
	156	res = (bbm->bbt[block >> 3] >> (block & 0x06)) & 0x03;
	157
3167c538	158	MTDDEBUG (MTD_DEBUG_LEVEL2,
ef0921d6 KP	159	"onenand_isbad_bbt: bbt info for offs 0x%08x: (block %d) 0x%02x\n",
ef0921d6 KP	160	(unsigned int)offs, block >> 1, res);
17aa2800 KP	161
	162	switch ((int)res) {
	163	case 0x00:
	164	return 0;
	165	case 0x01:
	166	return 1;
	167	case 0x02:
	168	return allowbbt ? 0 : 1;
	169	}
	170
	171	return 1;
	172	}
	173
	174	/**
	175	* onenand_scan_bbt - [OneNAND Interface] scan, find, read and maybe create bad block table(s)
	176	* @param mtd MTD device structure
	177	* @param bd descriptor for the good/bad block search pattern
	178	*
	179	* The function checks, if a bad block table(s) is/are already
	180	* available. If not it scans the device for manufacturer
	181	* marked good / bad blocks and writes the bad block table(s) to
	182	* the selected place.
	183	*
	184	* The bad block table memory is allocated here. It must be freed
	185	* by calling the onenand_free_bbt function.
	186	*
	187	*/
	188	int onenand_scan_bbt(struct mtd_info mtd, struct nand_bbt_descr bd)
	189	{
	190	struct onenand_chip *this = mtd->priv;
	191	struct bbm_info *bbm = this->bbm;
	192	int len, ret = 0;
	193
	194	len = mtd->size >> (this->erase_shift + 2);
	195	/* Allocate memory (2bit per block) */
	196	bbm->bbt = malloc(len);
	197	if (!bbm->bbt) {
	198	printk(KERN_ERR "onenand_scan_bbt: Out of memory\n");
	199	return -ENOMEM;
	200	}
	201	/* Clear the memory bad block table */
	202	memset(bbm->bbt, 0x00, len);
	203
	204	/* Set the bad block position */
	205	bbm->badblockpos = ONENAND_BADBLOCK_POS;
	206
	207	/* Set erase shift */
	208	bbm->bbt_erase_shift = this->erase_shift;
	209
	210	if (!bbm->isbad_bbt)
	211	bbm->isbad_bbt = onenand_isbad_bbt;
	212
	213	/* Scan the device to build a memory based bad block table */
	214	if ((ret = onenand_memory_bbt(mtd, bd))) {
	215	printk(KERN_ERR
	216	"onenand_scan_bbt: Can't scan flash and build the RAM-based BBT\n");
	217	free(bbm->bbt);
	218	bbm->bbt = NULL;
	219	}
	220
	221	return ret;
	222	}
	223
	224	/*
225	* Define some generic bad / good block scan pattern which are used
226	* while scanning a device for factory marked good / bad blocks.
227	*/
228	static uint8_t scan_ff_pattern[] = { 0xff, 0xff };
229
230	static struct nand_bbt_descr largepage_memorybased = {
231	.options = 0,
232	.offs = 0,
233	.len = 2,
234	.pattern = scan_ff_pattern,
235	};
236
237	/**
238	* onenand_default_bbt - [OneNAND Interface] Select a default bad block table for the device
239	* @param mtd MTD device structure
240	*
241	* This function selects the default bad block table
242	* support for the device and calls the onenand_scan_bbt function
243	*/
244	int onenand_default_bbt(struct mtd_info *mtd)
245	{
246	struct onenand_chip *this = mtd->priv;
247	struct bbm_info *bbm;
248
249	this->bbm = malloc(sizeof(struct bbm_info));
250	if (!this->bbm)
251	return -ENOMEM;
252
253	bbm = this->bbm;
254
255	memset(bbm, 0, sizeof(struct bbm_info));
256
257	/* 1KB page has same configuration as 2KB page */
258	if (!bbm->badblock_pattern)
259	bbm->badblock_pattern = &largepage_memorybased;
260
261	return onenand_scan_bbt(mtd, bbm->badblock_pattern);
262	}