u-boot/fs/yaffs2/yaffs_ecc.h
William Juul 0e8cc8bd92 YAFFS2 import
Direct import of yaffs as a tarball as of 20071113 from their public
CVS-web at http://www.aleph1.co.uk/cgi-bin/viewcvs.cgi/yaffs2/

The code can also be imported on the command line with:
export CVSROOT=:pserver:anonymous@cvs.aleph1.co.uk:/home/aleph1/cvs cvs logon
(Hit return when asked for a password)
cvs checkout yaffs2

Signed-off-by: William Juul <william.juul@tandberg.com>
Signed-off-by: Stig Olsen <stig.olsen@tandberg.com>
2008-08-12 11:31:18 -05:00

44 lines
1.4 KiB
C

/*
* YAFFS: Yet another Flash File System . A NAND-flash specific file system.
*
* Copyright (C) 2002-2007 Aleph One Ltd.
* for Toby Churchill Ltd and Brightstar Engineering
*
* Created by Charles Manning <charles@aleph1.co.uk>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License version 2.1 as
* published by the Free Software Foundation.
*
* Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
*/
/*
* This code implements the ECC algorithm used in SmartMedia.
*
* The ECC comprises 22 bits of parity information and is stuffed into 3 bytes.
* The two unused bit are set to 1.
* The ECC can correct single bit errors in a 256-byte page of data. Thus, two such ECC
* blocks are used on a 512-byte NAND page.
*
*/
#ifndef __YAFFS_ECC_H__
#define __YAFFS_ECC_H__
typedef struct {
unsigned char colParity;
unsigned lineParity;
unsigned lineParityPrime;
} yaffs_ECCOther;
void yaffs_ECCCalculate(const unsigned char *data, unsigned char *ecc);
int yaffs_ECCCorrect(unsigned char *data, unsigned char *read_ecc,
const unsigned char *test_ecc);
void yaffs_ECCCalculateOther(const unsigned char *data, unsigned nBytes,
yaffs_ECCOther * ecc);
int yaffs_ECCCorrectOther(unsigned char *data, unsigned nBytes,
yaffs_ECCOther * read_ecc,
const yaffs_ECCOther * test_ecc);
#endif