193bd40026
This patch adds software BCH ECC support to mtd, in order to handle recent NAND device ecc requirements (4 bits or more). It does so by adding a new ecc mode (NAND_ECC_SOFT_BCH) for use by board drivers, and a new Kconfig option to enable BCH support. It relies on the generic BCH library introduced in a previous patch. When a board driver uses mode NAND_ECC_SOFT_BCH, it should also set fields chip->ecc.size and chip->ecc.bytes to select BCH ecc data size and required error correction capability. See nand_bch_init() documentation for details. It has been tested on the following platforms using mtd-utils, UBI and UBIFS: x86 (with nandsim), arm926ejs. Signed-off-by: Ivan Djelic <ivan.djelic@parrot.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
73 lines
1.7 KiB
C
73 lines
1.7 KiB
C
/*
|
|
* Copyright © 2011 Ivan Djelic <ivan.djelic@parrot.com>
|
|
*
|
|
* 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 file is the header for the NAND BCH ECC implementation.
|
|
*/
|
|
|
|
#ifndef __MTD_NAND_BCH_H__
|
|
#define __MTD_NAND_BCH_H__
|
|
|
|
struct mtd_info;
|
|
struct nand_bch_control;
|
|
|
|
#if defined(CONFIG_MTD_NAND_ECC_BCH)
|
|
|
|
static inline int mtd_nand_has_bch(void) { return 1; }
|
|
|
|
/*
|
|
* Calculate BCH ecc code
|
|
*/
|
|
int nand_bch_calculate_ecc(struct mtd_info *mtd, const u_char *dat,
|
|
u_char *ecc_code);
|
|
|
|
/*
|
|
* Detect and correct bit errors
|
|
*/
|
|
int nand_bch_correct_data(struct mtd_info *mtd, u_char *dat, u_char *read_ecc,
|
|
u_char *calc_ecc);
|
|
/*
|
|
* Initialize BCH encoder/decoder
|
|
*/
|
|
struct nand_bch_control *
|
|
nand_bch_init(struct mtd_info *mtd, unsigned int eccsize,
|
|
unsigned int eccbytes, struct nand_ecclayout **ecclayout);
|
|
/*
|
|
* Release BCH encoder/decoder resources
|
|
*/
|
|
void nand_bch_free(struct nand_bch_control *nbc);
|
|
|
|
#else /* !CONFIG_MTD_NAND_ECC_BCH */
|
|
|
|
static inline int mtd_nand_has_bch(void) { return 0; }
|
|
|
|
static inline int
|
|
nand_bch_calculate_ecc(struct mtd_info *mtd, const u_char *dat,
|
|
u_char *ecc_code)
|
|
{
|
|
return -1;
|
|
}
|
|
|
|
static inline int
|
|
nand_bch_correct_data(struct mtd_info *mtd, unsigned char *buf,
|
|
unsigned char *read_ecc, unsigned char *calc_ecc)
|
|
{
|
|
return -1;
|
|
}
|
|
|
|
static inline struct nand_bch_control *
|
|
nand_bch_init(struct mtd_info *mtd, unsigned int eccsize,
|
|
unsigned int eccbytes, struct nand_ecclayout **ecclayout)
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
static inline void nand_bch_free(struct nand_bch_control *nbc) {}
|
|
|
|
#endif /* CONFIG_MTD_NAND_ECC_BCH */
|
|
|
|
#endif /* __MTD_NAND_BCH_H__ */
|