Skip to content

Commit

Permalink
[MTD] NAND Add optional ECC status check callback
Browse files Browse the repository at this point in the history 
Add optional hardware specific callback routine to perform extra error
status checks on erase and write failures for devices with hardware ECC.

Signed-off-by: David A. Marlin <dmarlin@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
  • Loading branch information
David A. Marlin authored and Thomas Gleixner committed May 23, 2005
1 parent 99f2a8a commit 068e3c0
Show file tree
Hide file tree
Showing 2 changed files with 68 additions and 13 deletions.
65 changes: 54 additions & 11 deletions drivers/mtd/nand/nand_base.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -42,6 +42,10 @@
* a "device recovery" operation must be performed when power is restored
* to ensure correct operation.
*
* 01-20-2005 dmarlin: added support for optional hardware specific callback routine to
* perform extra error status checks on erase and write failures. This required
* adding a wrapper function for nand_read_ecc.
*
* Credits:
* David Woodhouse for adding multichip support
*
Expand All @@ -55,7 +59,7 @@
* The AG-AND chips have nice features for speed improvement,
* which are not supported yet. Read / program 4 pages in one go.
*
* $Id: nand_base.c,v 1.129 2005/01/23 18:30:50 dmarlin Exp $
* $Id: nand_base.c,v 1.130 2005/01/24 03:07:43 dmarlin Exp $
*
* 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
Expand Down Expand Up @@ -896,6 +900,12 @@ static int nand_write_page (struct mtd_info *mtd, struct nand_chip *this, int pa
if (!cached) {
/* call wait ready function */
status = this->waitfunc (mtd, this, FL_WRITING);

/* See if operation failed and additional status checks are available */
if ((status & NAND_STATUS_FAIL) && (this->errstat)) {
status = this->errstat(mtd, this, FL_WRITING, status, page);
}

/* See if device thinks it succeeded */
if (status & NAND_STATUS_FAIL) {
DEBUG (MTD_DEBUG_LEVEL0, "%s: " "Failed write, page 0x%08x, ", __FUNCTION__, page);
Expand Down Expand Up @@ -1022,23 +1032,24 @@ static int nand_verify_pages (struct mtd_info *mtd, struct nand_chip *this, int
#endif

/**
* nand_read - [MTD Interface] MTD compability function for nand_read_ecc
* nand_read - [MTD Interface] MTD compability function for nand_do_read_ecc
* @mtd: MTD device structure
* @from: offset to read from
* @len: number of bytes to read
* @retlen: pointer to variable to store the number of read bytes
* @buf: the databuffer to put data
*
* This function simply calls nand_read_ecc with oob buffer and oobsel = NULL
*/
* This function simply calls nand_do_read_ecc with oob buffer and oobsel = NULL
* and flags = 0xff
*/
static int nand_read (struct mtd_info *mtd, loff_t from, size_t len, size_t * retlen, u_char * buf)
{
return nand_read_ecc (mtd, from, len, retlen, buf, NULL, NULL);
return nand_do_read_ecc (mtd, from, len, retlen, buf, NULL, NULL, 0xff);
}


/**
* nand_read_ecc - [MTD Interface] Read data with ECC
* nand_read_ecc - [MTD Interface] MTD compability function for nand_do_read_ecc
* @mtd: MTD device structure
* @from: offset to read from
* @len: number of bytes to read
Expand All @@ -1047,10 +1058,34 @@ static int nand_read (struct mtd_info *mtd, loff_t from, size_t len, size_t * re
* @oob_buf: filesystem supplied oob data buffer
* @oobsel: oob selection structure
*
* NAND read with ECC
* This function simply calls nand_do_read_ecc with flags = 0xff
*/
static int nand_read_ecc (struct mtd_info *mtd, loff_t from, size_t len,
size_t * retlen, u_char * buf, u_char * oob_buf, struct nand_oobinfo *oobsel)
{
return nand_do_read_ecc(mtd, from, len, retlen, buf, oob_buf, oobsel, 0xff);
}


/**
* nand_do_read_ecc - [MTD Interface] Read data with ECC
* @mtd: MTD device structure
* @from: offset to read from
* @len: number of bytes to read
* @retlen: pointer to variable to store the number of read bytes
* @buf: the databuffer to put data
* @oob_buf: filesystem supplied oob data buffer
* @oobsel: oob selection structure
* @flags: flag to indicate if nand_get_device/nand_release_device should be preformed
* and how many corrected error bits are acceptable:
* bits 0..7 - number of tolerable errors
* bit 8 - 0 == do not get/release chip, 1 == get/release chip
*
* NAND read with ECC
*/
int nand_do_read_ecc (struct mtd_info *mtd, loff_t from, size_t len,
size_t * retlen, u_char * buf, u_char * oob_buf,
struct nand_oobinfo *oobsel, int flags)
{
int i, j, col, realpage, page, end, ecc, chipnr, sndcmd = 1;
int read = 0, oob = 0, ecc_status = 0, ecc_failed = 0;
Expand All @@ -1076,7 +1111,8 @@ static int nand_read_ecc (struct mtd_info *mtd, loff_t from, size_t len,
}

/* Grab the lock and see if the device is available */
nand_get_device (this, mtd, FL_READING);
if (flags & NAND_GET_DEVICE)
nand_get_device (this, mtd, FL_READING);

/* use userspace supplied oobinfo, if zero */
if (oobsel == NULL)
Expand Down Expand Up @@ -1180,7 +1216,8 @@ static int nand_read_ecc (struct mtd_info *mtd, loff_t from, size_t len,
/* We calc error correction directly, it checks the hw
* generator for an error, reads back the syndrome and
* does the error correction on the fly */
if (this->correct_data(mtd, &data_poi[datidx], &oob_data[i], &ecc_code[i]) == -1) {
ecc_status = this->correct_data(mtd, &data_poi[datidx], &oob_data[i], &ecc_code[i]);
if ((ecc_status == -1) || (ecc_status > (flags && 0xff))) {
DEBUG (MTD_DEBUG_LEVEL0, "nand_read_ecc: "
"Failed ECC read, page 0x%08x on chip %d\n", page, chipnr);
ecc_failed++;
Expand Down Expand Up @@ -1219,7 +1256,7 @@ static int nand_read_ecc (struct mtd_info *mtd, loff_t from, size_t len,
p[i] = ecc_status;
}

if (ecc_status == -1) {
if ((ecc_status == -1) || (ecc_status > (flags && 0xff))) {
DEBUG (MTD_DEBUG_LEVEL0, "nand_read_ecc: " "Failed ECC read, page 0x%08x\n", page);
ecc_failed++;
}
Expand Down Expand Up @@ -1289,7 +1326,8 @@ static int nand_read_ecc (struct mtd_info *mtd, loff_t from, size_t len,
}

/* Deselect and wake up anyone waiting on the device */
nand_release_device(mtd);
if (flags & NAND_GET_DEVICE)
nand_release_device(mtd);

/*
* Return success, if no ECC failures, else -EBADMSG
Expand Down Expand Up @@ -2103,6 +2141,11 @@ int nand_erase_nand (struct mtd_info *mtd, struct erase_info *instr, int allowbb

status = this->waitfunc (mtd, this, FL_ERASING);

/* See if operation failed and additional status checks are available */
if ((status & NAND_STATUS_FAIL) && (this->errstat)) {
status = this->errstat(mtd, this, FL_ERASING, status, page);
}

/* See if block erase succeeded */
if (status & NAND_STATUS_FAIL) {
DEBUG (MTD_DEBUG_LEVEL0, "nand_erase: " "Failed erase, page 0x%08x\n", page);
Expand Down
16 changes: 14 additions & 2 deletions include/linux/mtd/nand.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -5,7 +5,7 @@
* Steven J. Hill <sjhill@realitydiluted.com>
* Thomas Gleixner <tglx@linutronix.de>
*
* $Id: nand.h,v 1.69 2005/01/17 18:29:18 dmarlin Exp $
* $Id: nand.h,v 1.70 2005/01/24 03:07:42 dmarlin Exp $
*
* 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
Expand Down Expand Up @@ -50,6 +50,8 @@
* update of nand_chip structure description
* 01-17-2005 dmarlin added extended commands for AG-AND device and added option
* for BBT_AUTO_REFRESH.
* 01-20-2005 dmarlin added optional pointer to hardware specific callback for
* extra error status checks.
*/
#ifndef __LINUX_MTD_NAND_H
#define __LINUX_MTD_NAND_H
Expand Down Expand Up @@ -164,14 +166,18 @@ extern int nand_read_raw (struct mtd_info *mtd, uint8_t *buf, loff_t from, size_

/*
* Constants for Hardware ECC
*/
*/
/* Reset Hardware ECC for read */
#define NAND_ECC_READ 0
/* Reset Hardware ECC for write */
#define NAND_ECC_WRITE 1
/* Enable Hardware ECC before syndrom is read back from flash */
#define NAND_ECC_READSYN 2

/* Bit mask for flags passed to do_nand_read_ecc */
#define NAND_GET_DEVICE 0x80


/* Option constants for bizarre disfunctionality and real
* features
*/
Expand Down Expand Up @@ -308,6 +314,8 @@ struct nand_hw_control {
* @badblock_pattern: [REPLACEABLE] bad block scan pattern used for initial bad block scan
* @controller: [OPTIONAL] a pointer to a hardware controller structure which is shared among multiple independend devices
* @priv: [OPTIONAL] pointer to private chip date
* @errstat: [OPTIONAL] hardware specific function to perform additional error status checks
* (determine if errors are correctable)
*/

struct nand_chip {
Expand Down Expand Up @@ -363,6 +371,7 @@ struct nand_chip {
struct nand_bbt_descr *badblock_pattern;
struct nand_hw_control *controller;
void *priv;
int (*errstat)(struct mtd_info *mtd, struct nand_chip *this, int state, int status, int page);
};

/*
Expand Down Expand Up @@ -484,6 +493,9 @@ extern int nand_update_bbt (struct mtd_info *mtd, loff_t offs);
extern int nand_default_bbt (struct mtd_info *mtd);
extern int nand_isbad_bbt (struct mtd_info *mtd, loff_t offs, int allowbbt);
extern int nand_erase_nand (struct mtd_info *mtd, struct erase_info *instr, int allowbbt);
extern int nand_do_read_ecc (struct mtd_info *mtd, loff_t from, size_t len,
size_t * retlen, u_char * buf, u_char * oob_buf,
struct nand_oobinfo *oobsel, int flags);

/*
* Constants for oob configuration
Expand Down

0 comments on commit 068e3c0

Please sign in to comment.