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gerrit-public.fairphone.software / kernel / msm-4.19 / ba78ee00e1ff84de9b3ad33edbd3ec599099ee82 / . / drivers / mtd / nand / nand_base.c
blob: 6669dfcf9e794e1d9727bb6e58097fdb5ac7e65a [file] [log] [blame]
/*
* Overview:
* This is the generic MTD driver for NAND flash devices. It should be
* capable of working with almost all NAND chips currently available.
*
* Additional technical information is available on
* http://www.linux-mtd.infradead.org/doc/nand.html
*
* Copyright (C) 2000 Steven J. Hill (sjhill@realitydiluted.com)
* 2002-2006 Thomas Gleixner (tglx@linutronix.de)
*
* Credits:
* David Woodhouse for adding multichip support
*
* Aleph One Ltd. and Toby Churchill Ltd. for supporting the
* rework for 2K page size chips
*
* TODO:
* Enable cached programming for 2k page size chips
* Check, if mtd->ecctype should be set to MTD_ECC_HW
* if we have HW ECC support.
* BBT table is not serialized, has to be fixed
*
* 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.
*
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/types.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/nand.h>
#include <linux/mtd/nand_ecc.h>
#include <linux/mtd/nand_bch.h>
#include <linux/interrupt.h>
#include <linux/bitops.h>
#include <linux/io.h>
#include <linux/mtd/partitions.h>
#include <linux/of.h>
static int nand_get_device(struct mtd_info *mtd, int new_state);
static int nand_do_write_oob(struct mtd_info *mtd, loff_t to,
struct mtd_oob_ops *ops);
/* Define default oob placement schemes for large and small page devices */
static int nand_ooblayout_ecc_sp(struct mtd_info *mtd, int section,
struct mtd_oob_region *oobregion)
{
struct nand_chip *chip = mtd_to_nand(mtd);
struct nand_ecc_ctrl *ecc = &chip->ecc;
if (section > 1)
return -ERANGE;
if (!section) {
oobregion->offset = 0;
oobregion->length = 4;
} else {
oobregion->offset = 6;
oobregion->length = ecc->total - 4;
}
return 0;
}
static int nand_ooblayout_free_sp(struct mtd_info *mtd, int section,
struct mtd_oob_region *oobregion)
{
if (section > 1)
return -ERANGE;
if (mtd->oobsize == 16) {
if (section)
return -ERANGE;
oobregion->length = 8;
oobregion->offset = 8;
} else {
oobregion->length = 2;
if (!section)
oobregion->offset = 3;
else
oobregion->offset = 6;
}
return 0;
}
const struct mtd_ooblayout_ops nand_ooblayout_sp_ops = {
.ecc = nand_ooblayout_ecc_sp,
.free = nand_ooblayout_free_sp,
};
EXPORT_SYMBOL_GPL(nand_ooblayout_sp_ops);
static int nand_ooblayout_ecc_lp(struct mtd_info *mtd, int section,
struct mtd_oob_region *oobregion)
{
struct nand_chip *chip = mtd_to_nand(mtd);
struct nand_ecc_ctrl *ecc = &chip->ecc;
if (section)
return -ERANGE;
oobregion->length = ecc->total;
oobregion->offset = mtd->oobsize - oobregion->length;
return 0;
}
static int nand_ooblayout_free_lp(struct mtd_info *mtd, int section,
struct mtd_oob_region *oobregion)
{
struct nand_chip *chip = mtd_to_nand(mtd);
struct nand_ecc_ctrl *ecc = &chip->ecc;
if (section)
return -ERANGE;
oobregion->length = mtd->oobsize - ecc->total - 2;
oobregion->offset = 2;
return 0;
}
const struct mtd_ooblayout_ops nand_ooblayout_lp_ops = {
.ecc = nand_ooblayout_ecc_lp,
.free = nand_ooblayout_free_lp,
};
EXPORT_SYMBOL_GPL(nand_ooblayout_lp_ops);
static int check_offs_len(struct mtd_info *mtd,
loff_t ofs, uint64_t len)
{
struct nand_chip *chip = mtd_to_nand(mtd);
int ret = 0;
/* Start address must align on block boundary */
if (ofs & ((1ULL << chip->phys_erase_shift) - 1)) {
pr_debug("%s: unaligned address\n", __func__);
ret = -EINVAL;
}
/* Length must align on block boundary */
if (len & ((1ULL << chip->phys_erase_shift) - 1)) {
pr_debug("%s: length not block aligned\n", __func__);
ret = -EINVAL;
}
return ret;
}
/**
* nand_release_device - [GENERIC] release chip
* @mtd: MTD device structure
*
* Release chip lock and wake up anyone waiting on the device.
*/
static void nand_release_device(struct mtd_info *mtd)
{
struct nand_chip *chip = mtd_to_nand(mtd);
/* Release the controller and the chip */
spin_lock(&chip->controller->lock);
chip->controller->active = NULL;
chip->state = FL_READY;
wake_up(&chip->controller->wq);
spin_unlock(&chip->controller->lock);
}
/**
* nand_read_byte - [DEFAULT] read one byte from the chip
* @mtd: MTD device structure
*
* Default read function for 8bit buswidth
*/
static uint8_t nand_read_byte(struct mtd_info *mtd)
{
struct nand_chip *chip = mtd_to_nand(mtd);
return readb(chip->IO_ADDR_R);
}
/**
* nand_read_byte16 - [DEFAULT] read one byte endianness aware from the chip
* @mtd: MTD device structure
*
* Default read function for 16bit buswidth with endianness conversion.
*
*/
static uint8_t nand_read_byte16(struct mtd_info *mtd)
{
struct nand_chip *chip = mtd_to_nand(mtd);
return (uint8_t) cpu_to_le16(readw(chip->IO_ADDR_R));
}
/**
* nand_read_word - [DEFAULT] read one word from the chip
* @mtd: MTD device structure
*
* Default read function for 16bit buswidth without endianness conversion.
*/
static u16 nand_read_word(struct mtd_info *mtd)
{
struct nand_chip *chip = mtd_to_nand(mtd);
return readw(chip->IO_ADDR_R);
}
/**
* nand_select_chip - [DEFAULT] control CE line
* @mtd: MTD device structure
* @chipnr: chipnumber to select, -1 for deselect
*
* Default select function for 1 chip devices.
*/
static void nand_select_chip(struct mtd_info *mtd, int chipnr)
{
struct nand_chip *chip = mtd_to_nand(mtd);
switch (chipnr) {
case -1:
chip->cmd_ctrl(mtd, NAND_CMD_NONE, 0 | NAND_CTRL_CHANGE);
break;
case 0:
break;
default:
BUG();
}
}
/**
* nand_write_byte - [DEFAULT] write single byte to chip
* @mtd: MTD device structure
* @byte: value to write
*
* Default function to write a byte to I/O[7:0]
*/
static void nand_write_byte(struct mtd_info *mtd, uint8_t byte)
{
struct nand_chip *chip = mtd_to_nand(mtd);
chip->write_buf(mtd, &byte, 1);
}
/**
* nand_write_byte16 - [DEFAULT] write single byte to a chip with width 16
* @mtd: MTD device structure
* @byte: value to write
*
* Default function to write a byte to I/O[7:0] on a 16-bit wide chip.
*/
static void nand_write_byte16(struct mtd_info *mtd, uint8_t byte)
{
struct nand_chip *chip = mtd_to_nand(mtd);
uint16_t word = byte;
/*
* It's not entirely clear what should happen to I/O[15:8] when writing
* a byte. The ONFi spec (Revision 3.1; 2012-09-19, Section 2.16) reads:
*
* When the host supports a 16-bit bus width, only data is
* transferred at the 16-bit width. All address and command line
* transfers shall use only the lower 8-bits of the data bus. During
* command transfers, the host may place any value on the upper
* 8-bits of the data bus. During address transfers, the host shall
* set the upper 8-bits of the data bus to 00h.
*
* One user of the write_byte callback is nand_onfi_set_features. The
* four parameters are specified to be written to I/O[7:0], but this is
* neither an address nor a command transfer. Let's assume a 0 on the
* upper I/O lines is OK.
*/
chip->write_buf(mtd, (uint8_t *)&word, 2);
}
/**
* nand_write_buf - [DEFAULT] write buffer to chip
* @mtd: MTD device structure
* @buf: data buffer
* @len: number of bytes to write
*
* Default write function for 8bit buswidth.
*/
static void nand_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
{
struct nand_chip *chip = mtd_to_nand(mtd);
iowrite8_rep(chip->IO_ADDR_W, buf, len);
}
/**
* nand_read_buf - [DEFAULT] read chip data into buffer
* @mtd: MTD device structure
* @buf: buffer to store date
* @len: number of bytes to read
*
* Default read function for 8bit buswidth.
*/
static void nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
{
struct nand_chip *chip = mtd_to_nand(mtd);
ioread8_rep(chip->IO_ADDR_R, buf, len);
}
/**
* nand_write_buf16 - [DEFAULT] write buffer to chip
* @mtd: MTD device structure
* @buf: data buffer
* @len: number of bytes to write
*
* Default write function for 16bit buswidth.
*/
static void nand_write_buf16(struct mtd_info *mtd, const uint8_t *buf, int len)
{
struct nand_chip *chip = mtd_to_nand(mtd);
u16 *p = (u16 *) buf;
iowrite16_rep(chip->IO_ADDR_W, p, len >> 1);
}
/**
* nand_read_buf16 - [DEFAULT] read chip data into buffer
* @mtd: MTD device structure
* @buf: buffer to store date
* @len: number of bytes to read
*
* Default read function for 16bit buswidth.
*/
static void nand_read_buf16(struct mtd_info *mtd, uint8_t *buf, int len)
{
struct nand_chip *chip = mtd_to_nand(mtd);
u16 *p = (u16 *) buf;
ioread16_rep(chip->IO_ADDR_R, p, len >> 1);
}
/**
* nand_block_bad - [DEFAULT] Read bad block marker from the chip
* @mtd: MTD device structure
* @ofs: offset from device start
*
* Check, if the block is bad.
*/
static int nand_block_bad(struct mtd_info *mtd, loff_t ofs)
{
int page, res = 0, i = 0;
struct nand_chip *chip = mtd_to_nand(mtd);
u16 bad;
if (chip->bbt_options & NAND_BBT_SCANLASTPAGE)
ofs += mtd->erasesize - mtd->writesize;
page = (int)(ofs >> chip->page_shift) & chip->pagemask;
do {
if (chip->options & NAND_BUSWIDTH_16) {
chip->cmdfunc(mtd, NAND_CMD_READOOB,
chip->badblockpos & 0xFE, page);
bad = cpu_to_le16(chip->read_word(mtd));
if (chip->badblockpos & 0x1)
bad >>= 8;
else
bad &= 0xFF;
} else {
chip->cmdfunc(mtd, NAND_CMD_READOOB, chip->badblockpos,
page);
bad = chip->read_byte(mtd);
}
if (likely(chip->badblockbits == 8))
res = bad != 0xFF;
else
res = hweight8(bad) < chip->badblockbits;
ofs += mtd->writesize;
page = (int)(ofs >> chip->page_shift) & chip->pagemask;
i++;
} while (!res && i < 2 && (chip->bbt_options & NAND_BBT_SCAN2NDPAGE));
return res;
}
/**
* nand_default_block_markbad - [DEFAULT] mark a block bad via bad block marker
* @mtd: MTD device structure
* @ofs: offset from device start
*
* This is the default implementation, which can be overridden by a hardware
* specific driver. It provides the details for writing a bad block marker to a
* block.
*/
static int nand_default_block_markbad(struct mtd_info *mtd, loff_t ofs)
{
struct nand_chip *chip = mtd_to_nand(mtd);
struct mtd_oob_ops ops;
uint8_t buf[2] = { 0, 0 };
int ret = 0, res, i = 0;
memset(&ops, 0, sizeof(ops));
ops.oobbuf = buf;
ops.ooboffs = chip->badblockpos;
if (chip->options & NAND_BUSWIDTH_16) {
ops.ooboffs &= ~0x01;
ops.len = ops.ooblen = 2;
} else {
ops.len = ops.ooblen = 1;
}
ops.mode = MTD_OPS_PLACE_OOB;
/* Write to first/last page(s) if necessary */
if (chip->bbt_options & NAND_BBT_SCANLASTPAGE)
ofs += mtd->erasesize - mtd->writesize;
do {
res = nand_do_write_oob(mtd, ofs, &ops);
if (!ret)
ret = res;
i++;
ofs += mtd->writesize;
} while ((chip->bbt_options & NAND_BBT_SCAN2NDPAGE) && i < 2);
return ret;
}
/**
* nand_block_markbad_lowlevel - mark a block bad
* @mtd: MTD device structure
* @ofs: offset from device start
*
* This function performs the generic NAND bad block marking steps (i.e., bad
* block table(s) and/or marker(s)). We only allow the hardware driver to
* specify how to write bad block markers to OOB (chip->block_markbad).
*
* We try operations in the following order:
* (1) erase the affected block, to allow OOB marker to be written cleanly
* (2) write bad block marker to OOB area of affected block (unless flag
* NAND_BBT_NO_OOB_BBM is present)
* (3) update the BBT
* Note that we retain the first error encountered in (2) or (3), finish the
* procedures, and dump the error in the end.
*/
static int nand_block_markbad_lowlevel(struct mtd_info *mtd, loff_t ofs)
{
struct nand_chip *chip = mtd_to_nand(mtd);
int res, ret = 0;
if (!(chip->bbt_options & NAND_BBT_NO_OOB_BBM)) {
struct erase_info einfo;
/* Attempt erase before marking OOB */
memset(&einfo, 0, sizeof(einfo));
einfo.mtd = mtd;
einfo.addr = ofs;
einfo.len = 1ULL << chip->phys_erase_shift;
nand_erase_nand(mtd, &einfo, 0);
/* Write bad block marker to OOB */
nand_get_device(mtd, FL_WRITING);
ret = chip->block_markbad(mtd, ofs);
nand_release_device(mtd);
}
/* Mark block bad in BBT */
if (chip->bbt) {
res = nand_markbad_bbt(mtd, ofs);
if (!ret)
ret = res;
}
if (!ret)
mtd->ecc_stats.badblocks++;
return ret;
}
/**
* nand_check_wp - [GENERIC] check if the chip is write protected
* @mtd: MTD device structure
*
* Check, if the device is write protected. The function expects, that the
* device is already selected.
*/
static int nand_check_wp(struct mtd_info *mtd)
{
struct nand_chip *chip = mtd_to_nand(mtd);
/* Broken xD cards report WP despite being writable */
if (chip->options & NAND_BROKEN_XD)
return 0;
/* Check the WP bit */
chip->cmdfunc(mtd, NAND_CMD_STATUS, -1, -1);
return (chip->read_byte(mtd) & NAND_STATUS_WP) ? 0 : 1;
}
/**
* nand_block_isreserved - [GENERIC] Check if a block is marked reserved.
* @mtd: MTD device structure
* @ofs: offset from device start
*
* Check if the block is marked as reserved.
*/
static int nand_block_isreserved(struct mtd_info *mtd, loff_t ofs)
{
struct nand_chip *chip = mtd_to_nand(mtd);
if (!chip->bbt)
return 0;
/* Return info from the table */
return nand_isreserved_bbt(mtd, ofs);
}
/**
* nand_block_checkbad - [GENERIC] Check if a block is marked bad
* @mtd: MTD device structure
* @ofs: offset from device start
* @allowbbt: 1, if its allowed to access the bbt area
*
* Check, if the block is bad. Either by reading the bad block table or
* calling of the scan function.
*/
static int nand_block_checkbad(struct mtd_info *mtd, loff_t ofs, int allowbbt)
{
struct nand_chip *chip = mtd_to_nand(mtd);
if (!chip->bbt)
return chip->block_bad(mtd, ofs);
/* Return info from the table */
return nand_isbad_bbt(mtd, ofs, allowbbt);
}
/**
* panic_nand_wait_ready - [GENERIC] Wait for the ready pin after commands.
* @mtd: MTD device structure
* @timeo: Timeout
*
* Helper function for nand_wait_ready used when needing to wait in interrupt
* context.
*/
static void panic_nand_wait_ready(struct mtd_info *mtd, unsigned long timeo)
{
struct nand_chip *chip = mtd_to_nand(mtd);
int i;
/* Wait for the device to get ready */
for (i = 0; i < timeo; i++) {
if (chip->dev_ready(mtd))
break;
touch_softlockup_watchdog();
mdelay(1);
}
}
/**
* nand_wait_ready - [GENERIC] Wait for the ready pin after commands.
* @mtd: MTD device structure
*
* Wait for the ready pin after a command, and warn if a timeout occurs.
*/
void nand_wait_ready(struct mtd_info *mtd)
{
struct nand_chip *chip = mtd_to_nand(mtd);
unsigned long timeo = 400;
if (in_interrupt() || oops_in_progress)
return panic_nand_wait_ready(mtd, timeo);
/* Wait until command is processed or timeout occurs */
timeo = jiffies + msecs_to_jiffies(timeo);
do {
if (chip->dev_ready(mtd))
return;
cond_resched();
} while (time_before(jiffies, timeo));
if (!chip->dev_ready(mtd))
pr_warn_ratelimited("timeout while waiting for chip to become ready\n");
}
EXPORT_SYMBOL_GPL(nand_wait_ready);
/**
* nand_wait_status_ready - [GENERIC] Wait for the ready status after commands.
* @mtd: MTD device structure
* @timeo: Timeout in ms
*
* Wait for status ready (i.e. command done) or timeout.
*/
static void nand_wait_status_ready(struct mtd_info *mtd, unsigned long timeo)
{
register struct nand_chip *chip = mtd_to_nand(mtd);
timeo = jiffies + msecs_to_jiffies(timeo);
do {
if ((chip->read_byte(mtd) & NAND_STATUS_READY))
break;
touch_softlockup_watchdog();
} while (time_before(jiffies, timeo));
};
/**
* nand_command - [DEFAULT] Send command to NAND device
* @mtd: MTD device structure
* @command: the command to be sent
* @column: the column address for this command, -1 if none
* @page_addr: the page address for this command, -1 if none
*
* Send command to NAND device. This function is used for small page devices
* (512 Bytes per page).
*/
static void nand_command(struct mtd_info *mtd, unsigned int command,
int column, int page_addr)
{
register struct nand_chip *chip = mtd_to_nand(mtd);
int ctrl = NAND_CTRL_CLE | NAND_CTRL_CHANGE;
/* Write out the command to the device */
if (command == NAND_CMD_SEQIN) {
int readcmd;
if (column >= mtd->writesize) {
/* OOB area */
column -= mtd->writesize;
readcmd = NAND_CMD_READOOB;
} else if (column < 256) {
/* First 256 bytes --> READ0 */
readcmd = NAND_CMD_READ0;
} else {
column -= 256;
readcmd = NAND_CMD_READ1;
}
chip->cmd_ctrl(mtd, readcmd, ctrl);
ctrl &= ~NAND_CTRL_CHANGE;
}
chip->cmd_ctrl(mtd, command, ctrl);
/* Address cycle, when necessary */
ctrl = NAND_CTRL_ALE | NAND_CTRL_CHANGE;
/* Serially input address */
if (column != -1) {
/* Adjust columns for 16 bit buswidth */
if (chip->options & NAND_BUSWIDTH_16 &&
!nand_opcode_8bits(command))
column >>= 1;
chip->cmd_ctrl(mtd, column, ctrl);
ctrl &= ~NAND_CTRL_CHANGE;
}
if (page_addr != -1) {
chip->cmd_ctrl(mtd, page_addr, ctrl);
ctrl &= ~NAND_CTRL_CHANGE;
chip->cmd_ctrl(mtd, page_addr >> 8, ctrl);
/* One more address cycle for devices > 32MiB */
if (chip->chipsize > (32 << 20))
chip->cmd_ctrl(mtd, page_addr >> 16, ctrl);
}
chip->cmd_ctrl(mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
/*
* Program and erase have their own busy handlers status and sequential
* in needs no delay
*/
switch (command) {
case NAND_CMD_PAGEPROG:
case NAND_CMD_ERASE1:
case NAND_CMD_ERASE2:
case NAND_CMD_SEQIN:
case NAND_CMD_STATUS:
return;
case NAND_CMD_RESET:
if (chip->dev_ready)
break;
udelay(chip->chip_delay);
chip->cmd_ctrl(mtd, NAND_CMD_STATUS,
NAND_CTRL_CLE | NAND_CTRL_CHANGE);
chip->cmd_ctrl(mtd,
NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
/* EZ-NAND can take upto 250ms as per ONFi v4.0 */
nand_wait_status_ready(mtd, 250);
return;
/* This applies to read commands */
default:
/*
* If we don't have access to the busy pin, we apply the given
* command delay
*/
if (!chip->dev_ready) {
udelay(chip->chip_delay);
return;
}
}
/*
* Apply this short delay always to ensure that we do wait tWB in
* any case on any machine.
*/
ndelay(100);
nand_wait_ready(mtd);
}
/**
* nand_command_lp - [DEFAULT] Send command to NAND large page device
* @mtd: MTD device structure
* @command: the command to be sent
* @column: the column address for this command, -1 if none
* @page_addr: the page address for this command, -1 if none
*
* Send command to NAND device. This is the version for the new large page
* devices. We don't have the separate regions as we have in the small page
* devices. We must emulate NAND_CMD_READOOB to keep the code compatible.
*/
static void nand_command_lp(struct mtd_info *mtd, unsigned int command,
int column, int page_addr)
{
register struct nand_chip *chip = mtd_to_nand(mtd);
/* Emulate NAND_CMD_READOOB */
if (command == NAND_CMD_READOOB) {
column += mtd->writesize;
command = NAND_CMD_READ0;
}
/* Command latch cycle */
chip->cmd_ctrl(mtd, command, NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
if (column != -1 || page_addr != -1) {
int ctrl = NAND_CTRL_CHANGE | NAND_NCE | NAND_ALE;
/* Serially input address */
if (column != -1) {
/* Adjust columns for 16 bit buswidth */
if (chip->options & NAND_BUSWIDTH_16 &&
!nand_opcode_8bits(command))
column >>= 1;
chip->cmd_ctrl(mtd, column, ctrl);
ctrl &= ~NAND_CTRL_CHANGE;
chip->cmd_ctrl(mtd, column >> 8, ctrl);
}
if (page_addr != -1) {
chip->cmd_ctrl(mtd, page_addr, ctrl);
chip->cmd_ctrl(mtd, page_addr >> 8,
NAND_NCE | NAND_ALE);
/* One more address cycle for devices > 128MiB */
if (chip->chipsize > (128 << 20))
chip->cmd_ctrl(mtd, page_addr >> 16,
NAND_NCE | NAND_ALE);
}
}
chip->cmd_ctrl(mtd, NAND_CMD_NONE, NAND_NCE | NAND_CTRL_CHANGE);
/*
* Program and erase have their own busy handlers status, sequential
* in and status need no delay.
*/
switch (command) {
case NAND_CMD_CACHEDPROG:
case NAND_CMD_PAGEPROG:
case NAND_CMD_ERASE1:
case NAND_CMD_ERASE2:
case NAND_CMD_SEQIN:
case NAND_CMD_RNDIN:
case NAND_CMD_STATUS:
return;
case NAND_CMD_RESET:
if (chip->dev_ready)
break;
udelay(chip->chip_delay);
chip->cmd_ctrl(mtd, NAND_CMD_STATUS,
NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
chip->cmd_ctrl(mtd, NAND_CMD_NONE,
NAND_NCE | NAND_CTRL_CHANGE);
/* EZ-NAND can take upto 250ms as per ONFi v4.0 */
nand_wait_status_ready(mtd, 250);
return;
case NAND_CMD_RNDOUT:
/* No ready / busy check necessary */
chip->cmd_ctrl(mtd, NAND_CMD_RNDOUTSTART,
NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
chip->cmd_ctrl(mtd, NAND_CMD_NONE,
NAND_NCE | NAND_CTRL_CHANGE);
return;
case NAND_CMD_READ0:
chip->cmd_ctrl(mtd, NAND_CMD_READSTART,
NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
chip->cmd_ctrl(mtd, NAND_CMD_NONE,
NAND_NCE | NAND_CTRL_CHANGE);
/* This applies to read commands */
default:
/*
* If we don't have access to the busy pin, we apply the given
* command delay.
*/
if (!chip->dev_ready) {
udelay(chip->chip_delay);
return;
}
}
/*
* Apply this short delay always to ensure that we do wait tWB in
* any case on any machine.
*/
ndelay(100);
nand_wait_ready(mtd);
}
/**
* panic_nand_get_device - [GENERIC] Get chip for selected access
* @chip: the nand chip descriptor
* @mtd: MTD device structure
* @new_state: the state which is requested
*
* Used when in panic, no locks are taken.
*/
static void panic_nand_get_device(struct nand_chip *chip,
struct mtd_info *mtd, int new_state)
{
/* Hardware controller shared among independent devices */
chip->controller->active = chip;
chip->state = new_state;
}
/**
* nand_get_device - [GENERIC] Get chip for selected access
* @mtd: MTD device structure
* @new_state: the state which is requested
*
* Get the device and lock it for exclusive access
*/
static int
nand_get_device(struct mtd_info *mtd, int new_state)
{
struct nand_chip *chip = mtd_to_nand(mtd);
spinlock_t *lock = &chip->controller->lock;
wait_queue_head_t *wq = &chip->controller->wq;
DECLARE_WAITQUEUE(wait, current);
retry:
spin_lock(lock);
/* Hardware controller shared among independent devices */
if (!chip->controller->active)
chip->controller->active = chip;
if (chip->controller->active == chip && chip->state == FL_READY) {
chip->state = new_state;
spin_unlock(lock);
return 0;
}
if (new_state == FL_PM_SUSPENDED) {
if (chip->controller->active->state == FL_PM_SUSPENDED) {
chip->state = FL_PM_SUSPENDED;
spin_unlock(lock);
return 0;
}
}
set_current_state(TASK_UNINTERRUPTIBLE);
add_wait_queue(wq, &wait);
spin_unlock(lock);
schedule();
remove_wait_queue(wq, &wait);
goto retry;
}
/**
* panic_nand_wait - [GENERIC] wait until the command is done
* @mtd: MTD device structure
* @chip: NAND chip structure
* @timeo: timeout
*
* Wait for command done. This is a helper function for nand_wait used when
* we are in interrupt context. May happen when in panic and trying to write
* an oops through mtdoops.
*/
static void panic_nand_wait(struct mtd_info *mtd, struct nand_chip *chip,
unsigned long timeo)
{
int i;
for (i = 0; i < timeo; i++) {
if (chip->dev_ready) {
if (chip->dev_ready(mtd))
break;
} else {
if (chip->read_byte(mtd) & NAND_STATUS_READY)
break;
}
mdelay(1);
}
}
/**
* nand_wait - [DEFAULT] wait until the command is done
* @mtd: MTD device structure
* @chip: NAND chip structure
*
* Wait for command done. This applies to erase and program only.
*/
static int nand_wait(struct mtd_info *mtd, struct nand_chip *chip)
{
int status;
unsigned long timeo = 400;
/*
* Apply this short delay always to ensure that we do wait tWB in any
* case on any machine.
*/
ndelay(100);
chip->cmdfunc(mtd, NAND_CMD_STATUS, -1, -1);
if (in_interrupt() || oops_in_progress)
panic_nand_wait(mtd, chip, timeo);
else {
timeo = jiffies + msecs_to_jiffies(timeo);
do {
if (chip->dev_ready) {
if (chip->dev_ready(mtd))
break;
} else {
if (chip->read_byte(mtd) & NAND_STATUS_READY)
break;
}
cond_resched();
} while (time_before(jiffies, timeo));
}
status = (int)chip->read_byte(mtd);
/* This can happen if in case of timeout or buggy dev_ready */
WARN_ON(!(status & NAND_STATUS_READY));
return status;
}
/**
* nand_reset_data_interface - Reset data interface and timings
* @chip: The NAND chip
*
* Reset the Data interface and timings to ONFI mode 0.
*
* Returns 0 for success or negative error code otherwise.
*/
static int nand_reset_data_interface(struct nand_chip *chip)
{
struct mtd_info *mtd = nand_to_mtd(chip);
const struct nand_data_interface *conf;
int ret;
if (!chip->setup_data_interface)
return 0;
/*
* The ONFI specification says:
* "
* To transition from NV-DDR or NV-DDR2 to the SDR data
* interface, the host shall use the Reset (FFh) command
* using SDR timing mode 0. A device in any timing mode is
* required to recognize Reset (FFh) command issued in SDR
* timing mode 0.
* "
*
* Configure the data interface in SDR mode and set the
* timings to timing mode 0.
*/
conf = nand_get_default_data_interface();
ret = chip->setup_data_interface(mtd, conf, false);
if (ret)
pr_err("Failed to configure data interface to SDR timing mode 0\n");
return ret;
}
/**
* nand_setup_data_interface - Setup the best data interface and timings
* @chip: The NAND chip
*
* Find and configure the best data interface and NAND timings supported by
* the chip and the driver.
* First tries to retrieve supported timing modes from ONFI information,
* and if the NAND chip does not support ONFI, relies on the
* ->onfi_timing_mode_default specified in the nand_ids table.
*
* Returns 0 for success or negative error code otherwise.
*/
static int nand_setup_data_interface(struct nand_chip *chip)
{
struct mtd_info *mtd = nand_to_mtd(chip);
int ret;
if (!chip->setup_data_interface || !chip->data_interface)
return 0;
/*
* Ensure the timing mode has been changed on the chip side
* before changing timings on the controller side.
*/
if (chip->onfi_version) {
u8 tmode_param[ONFI_SUBFEATURE_PARAM_LEN] = {
chip->onfi_timing_mode_default,
};
ret = chip->onfi_set_features(mtd, chip,
ONFI_FEATURE_ADDR_TIMING_MODE,
tmode_param);
if (ret)
goto err;
}
ret = chip->setup_data_interface(mtd, chip->data_interface, false);
err:
return ret;
}
/**
* nand_init_data_interface - find the best data interface and timings
* @chip: The NAND chip
*
* Find the best data interface and NAND timings supported by the chip
* and the driver.
* First tries to retrieve supported timing modes from ONFI information,
* and if the NAND chip does not support ONFI, relies on the
* ->onfi_timing_mode_default specified in the nand_ids table. After this
* function nand_chip->data_interface is initialized with the best timing mode
* available.
*
* Returns 0 for success or negative error code otherwise.
*/
static int nand_init_data_interface(struct nand_chip *chip)
{
struct mtd_info *mtd = nand_to_mtd(chip);
int modes, mode, ret;
if (!chip->setup_data_interface)
return 0;
/*
* First try to identify the best timings from ONFI parameters and
* if the NAND does not support ONFI, fallback to the default ONFI
* timing mode.
*/
modes = onfi_get_async_timing_mode(chip);
if (modes == ONFI_TIMING_MODE_UNKNOWN) {
if (!chip->onfi_timing_mode_default)
return 0;
modes = GENMASK(chip->onfi_timing_mode_default, 0);
}
chip->data_interface = kzalloc(sizeof(*chip->data_interface),
GFP_KERNEL);
if (!chip->data_interface)
return -ENOMEM;
for (mode = fls(modes) - 1; mode >= 0; mode--) {
ret = onfi_init_data_interface(chip, chip->data_interface,
NAND_SDR_IFACE, mode);
if (ret)
continue;
ret = chip->setup_data_interface(mtd, chip->data_interface,
true);
if (!ret) {
chip->onfi_timing_mode_default = mode;
break;
}
}
return 0;
}
static void nand_release_data_interface(struct nand_chip *chip)
{
kfree(chip->data_interface);
}
/**
* nand_reset - Reset and initialize a NAND device
* @chip: The NAND chip
*
* Returns 0 for success or negative error code otherwise
*/
int nand_reset(struct nand_chip *chip)
{
struct mtd_info *mtd = nand_to_mtd(chip);
int ret;
ret = nand_reset_data_interface(chip);
if (ret)
return ret;
chip->cmdfunc(mtd, NAND_CMD_RESET, -1, -1);
ret = nand_setup_data_interface(chip);
if (ret)
return ret;
return 0;
}
/**
* __nand_unlock - [REPLACEABLE] unlocks specified locked blocks
* @mtd: mtd info
* @ofs: offset to start unlock from
* @len: length to unlock
* @invert: when = 0, unlock the range of blocks within the lower and
* upper boundary address
* when = 1, unlock the range of blocks outside the boundaries
* of the lower and upper boundary address
*
* Returs unlock status.
*/
static int __nand_unlock(struct mtd_info *mtd, loff_t ofs,
uint64_t len, int invert)
{
int ret = 0;
int status, page;
struct nand_chip *chip = mtd_to_nand(mtd);
/* Submit address of first page to unlock */
page = ofs >> chip->page_shift;
chip->cmdfunc(mtd, NAND_CMD_UNLOCK1, -1, page & chip->pagemask);
/* Submit address of last page to unlock */
page = (ofs + len) >> chip->page_shift;
chip->cmdfunc(mtd, NAND_CMD_UNLOCK2, -1,
(page | invert) & chip->pagemask);
/* Call wait ready function */
status = chip->waitfunc(mtd, chip);
/* See if device thinks it succeeded */
if (status & NAND_STATUS_FAIL) {
pr_debug("%s: error status = 0x%08x\n",
__func__, status);
ret = -EIO;
}
return ret;
}
/**
* nand_unlock - [REPLACEABLE] unlocks specified locked blocks
* @mtd: mtd info
* @ofs: offset to start unlock from
* @len: length to unlock
*
* Returns unlock status.
*/
int nand_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
{
int ret = 0;
int chipnr;
struct nand_chip *chip = mtd_to_nand(mtd);
pr_debug("%s: start = 0x%012llx, len = %llu\n",
__func__, (unsigned long long)ofs, len);
if (check_offs_len(mtd, ofs, len))
return -EINVAL;
/* Align to last block address if size addresses end of the device */
if (ofs + len == mtd->size)
len -= mtd->erasesize;
nand_get_device(mtd, FL_UNLOCKING);
/* Shift to get chip number */
chipnr = ofs >> chip->chip_shift;
chip->select_chip(mtd, chipnr);
/*
* Reset the chip.
* If we want to check the WP through READ STATUS and check the bit 7
* we must reset the chip
* some operation can also clear the bit 7 of status register
* eg. erase/program a locked block
*/
nand_reset(chip);
/* Check, if it is write protected */
if (nand_check_wp(mtd)) {
pr_debug("%s: device is write protected!\n",
__func__);
ret = -EIO;
goto out;
}
ret = __nand_unlock(mtd, ofs, len, 0);
out:
chip->select_chip(mtd, -1);
nand_release_device(mtd);
return ret;
}
EXPORT_SYMBOL(nand_unlock);
/**
* nand_lock - [REPLACEABLE] locks all blocks present in the device
* @mtd: mtd info
* @ofs: offset to start unlock from
* @len: length to unlock
*
* This feature is not supported in many NAND parts. 'Micron' NAND parts do
* have this feature, but it allows only to lock all blocks, not for specified
* range for block. Implementing 'lock' feature by making use of 'unlock', for
* now.
*
* Returns lock status.
*/
int nand_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
{
int ret = 0;
int chipnr, status, page;
struct nand_chip *chip = mtd_to_nand(mtd);
pr_debug("%s: start = 0x%012llx, len = %llu\n",
__func__, (unsigned long long)ofs, len);
if (check_offs_len(mtd, ofs, len))
return -EINVAL;
nand_get_device(mtd, FL_LOCKING);
/* Shift to get chip number */
chipnr = ofs >> chip->chip_shift;
chip->select_chip(mtd, chipnr);
/*
* Reset the chip.
* If we want to check the WP through READ STATUS and check the bit 7
* we must reset the chip
* some operation can also clear the bit 7 of status register
* eg. erase/program a locked block
*/
nand_reset(chip);
/* Check, if it is write protected */
if (nand_check_wp(mtd)) {
pr_debug("%s: device is write protected!\n",
__func__);
status = MTD_ERASE_FAILED;
ret = -EIO;
goto out;
}
/* Submit address of first page to lock */
page = ofs >> chip->page_shift;
chip->cmdfunc(mtd, NAND_CMD_LOCK, -1, page & chip->pagemask);
/* Call wait ready function */
status = chip->waitfunc(mtd, chip);
/* See if device thinks it succeeded */
if (status & NAND_STATUS_FAIL) {
pr_debug("%s: error status = 0x%08x\n",
__func__, status);
ret = -EIO;
goto out;
}
ret = __nand_unlock(mtd, ofs, len, 0x1);
out:
chip->select_chip(mtd, -1);
nand_release_device(mtd);
return ret;
}
EXPORT_SYMBOL(nand_lock);
/**
* nand_check_erased_buf - check if a buffer contains (almost) only 0xff data
* @buf: buffer to test
* @len: buffer length
* @bitflips_threshold: maximum number of bitflips
*
* Check if a buffer contains only 0xff, which means the underlying region
* has been erased and is ready to be programmed.
* The bitflips_threshold specify the maximum number of bitflips before
* considering the region is not erased.
* Note: The logic of this function has been extracted from the memweight
* implementation, except that nand_check_erased_buf function exit before
* testing the whole buffer if the number of bitflips exceed the
* bitflips_threshold value.
*
* Returns a positive number of bitflips less than or equal to
* bitflips_threshold, or -ERROR_CODE for bitflips in excess of the
* threshold.
*/
static int nand_check_erased_buf(void *buf, int len, int bitflips_threshold)
{
const unsigned char *bitmap = buf;
int bitflips = 0;
int weight;
for (; len && ((uintptr_t)bitmap) % sizeof(long);
len--, bitmap++) {
weight = hweight8(*bitmap);
bitflips += BITS_PER_BYTE - weight;
if (unlikely(bitflips > bitflips_threshold))
return -EBADMSG;
}
for (; len >= sizeof(long);
len -= sizeof(long), bitmap += sizeof(long)) {
weight = hweight_long(*((unsigned long *)bitmap));
bitflips += BITS_PER_LONG - weight;
if (unlikely(bitflips > bitflips_threshold))
return -EBADMSG;
}
for (; len > 0; len--, bitmap++) {
weight = hweight8(*bitmap);
bitflips += BITS_PER_BYTE - weight;
if (unlikely(bitflips > bitflips_threshold))
return -EBADMSG;
}
return bitflips;
}
/**
* nand_check_erased_ecc_chunk - check if an ECC chunk contains (almost) only
* 0xff data
* @data: data buffer to test
* @datalen: data length
* @ecc: ECC buffer
* @ecclen: ECC length
* @extraoob: extra OOB buffer
* @extraooblen: extra OOB length
* @bitflips_threshold: maximum number of bitflips
*
* Check if a data buffer and its associated ECC and OOB data contains only
* 0xff pattern, which means the underlying region has been erased and is
* ready to be programmed.
* The bitflips_threshold specify the maximum number of bitflips before
* considering the region as not erased.
*
* Note:
* 1/ ECC algorithms are working on pre-defined block sizes which are usually
* different from the NAND page size. When fixing bitflips, ECC engines will
* report the number of errors per chunk, and the NAND core infrastructure
* expect you to return the maximum number of bitflips for the whole page.
* This is why you should always use this function on a single chunk and
* not on the whole page. After checking each chunk you should update your
* max_bitflips value accordingly.
* 2/ When checking for bitflips in erased pages you should not only check
* the payload data but also their associated ECC data, because a user might
* have programmed almost all bits to 1 but a few. In this case, we
* shouldn't consider the chunk as erased, and checking ECC bytes prevent
* this case.
* 3/ The extraoob argument is optional, and should be used if some of your OOB
* data are protected by the ECC engine.
* It could also be used if you support subpages and want to attach some
* extra OOB data to an ECC chunk.
*
* Returns a positive number of bitflips less than or equal to
* bitflips_threshold, or -ERROR_CODE for bitflips in excess of the
* threshold. In case of success, the passed buffers are filled with 0xff.
*/
int nand_check_erased_ecc_chunk(void *data, int datalen,
void *ecc, int ecclen,
void *extraoob, int extraooblen,
int bitflips_threshold)
{
int data_bitflips = 0, ecc_bitflips = 0, extraoob_bitflips = 0;
data_bitflips = nand_check_erased_buf(data, datalen,
bitflips_threshold);
if (data_bitflips < 0)
return data_bitflips;
bitflips_threshold -= data_bitflips;
ecc_bitflips = nand_check_erased_buf(ecc, ecclen, bitflips_threshold);
if (ecc_bitflips < 0)
return ecc_bitflips;
bitflips_threshold -= ecc_bitflips;
extraoob_bitflips = nand_check_erased_buf(extraoob, extraooblen,
bitflips_threshold);
if (extraoob_bitflips < 0)
return extraoob_bitflips;
if (data_bitflips)
memset(data, 0xff, datalen);
if (ecc_bitflips)
memset(ecc, 0xff, ecclen);
if (extraoob_bitflips)
memset(extraoob, 0xff, extraooblen);
return data_bitflips + ecc_bitflips + extraoob_bitflips;
}
EXPORT_SYMBOL(nand_check_erased_ecc_chunk);
/**
* nand_read_page_raw - [INTERN] read raw page data without ecc
* @mtd: mtd info structure
* @chip: nand chip info structure
* @buf: buffer to store read data
* @oob_required: caller requires OOB data read to chip->oob_poi
* @page: page number to read
*
* Not for syndrome calculating ECC controllers, which use a special oob layout.
*/
static int nand_read_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
uint8_t *buf, int oob_required, int page)
{
chip->read_buf(mtd, buf, mtd->writesize);
if (oob_required)
chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
return 0;
}
/**
* nand_read_page_raw_syndrome - [INTERN] read raw page data without ecc
* @mtd: mtd info structure
* @chip: nand chip info structure
* @buf: buffer to store read data
* @oob_required: caller requires OOB data read to chip->oob_poi
* @page: page number to read
*
* We need a special oob layout and handling even when OOB isn't used.
*/
static int nand_read_page_raw_syndrome(struct mtd_info *mtd,
struct nand_chip *chip, uint8_t *buf,
int oob_required, int page)
{
int eccsize = chip->ecc.size;
int eccbytes = chip->ecc.bytes;
uint8_t *oob = chip->oob_poi;
int steps, size;
for (steps = chip->ecc.steps; steps > 0; steps--) {
chip->read_buf(mtd, buf, eccsize);
buf += eccsize;
if (chip->ecc.prepad) {
chip->read_buf(mtd, oob, chip->ecc.prepad);
oob += chip->ecc.prepad;
}
chip->read_buf(mtd, oob, eccbytes);
oob += eccbytes;
if (chip->ecc.postpad) {
chip->read_buf(mtd, oob, chip->ecc.postpad);
oob += chip->ecc.postpad;
}
}
size = mtd->oobsize - (oob - chip->oob_poi);
if (size)
chip->read_buf(mtd, oob, size);
return 0;
}
/**
* nand_read_page_swecc - [REPLACEABLE] software ECC based page read function
* @mtd: mtd info structure
* @chip: nand chip info structure
* @buf: buffer to store read data
* @oob_required: caller requires OOB data read to chip->oob_poi
* @page: page number to read
*/
static int nand_read_page_swecc(struct mtd_info *mtd, struct nand_chip *chip,
uint8_t *buf, int oob_required, int page)
{
int i, eccsize = chip->ecc.size, ret;
int eccbytes = chip->ecc.bytes;
int eccsteps = chip->ecc.steps;
uint8_t *p = buf;
uint8_t *ecc_calc = chip->buffers->ecccalc;
uint8_t *ecc_code = chip->buffers->ecccode;
unsigned int max_bitflips = 0;
chip->ecc.read_page_raw(mtd, chip, buf, 1, page);
for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize)
chip->ecc.calculate(mtd, p, &ecc_calc[i]);
ret = mtd_ooblayout_get_eccbytes(mtd, ecc_code, chip->oob_poi, 0,
chip->ecc.total);
if (ret)
return ret;
eccsteps = chip->ecc.steps;
p = buf;
for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
int stat;
stat = chip->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]);
if (stat < 0) {
mtd->ecc_stats.failed++;
} else {
mtd->ecc_stats.corrected += stat;
max_bitflips = max_t(unsigned int, max_bitflips, stat);
}
}
return max_bitflips;
}
/**
* nand_read_subpage - [REPLACEABLE] ECC based sub-page read function
* @mtd: mtd info structure
* @chip: nand chip info structure
* @data_offs: offset of requested data within the page
* @readlen: data length
* @bufpoi: buffer to store read data
* @page: page number to read
*/
static int nand_read_subpage(struct mtd_info *mtd, struct nand_chip *chip,
uint32_t data_offs, uint32_t readlen, uint8_t *bufpoi,
int page)
{
int start_step, end_step, num_steps, ret;
uint8_t *p;
int data_col_addr, i, gaps = 0;
int datafrag_len, eccfrag_len, aligned_len, aligned_pos;
int busw = (chip->options & NAND_BUSWIDTH_16) ? 2 : 1;
int index, section = 0;
unsigned int max_bitflips = 0;
struct mtd_oob_region oobregion = { };
/* Column address within the page aligned to ECC size (256bytes) */
start_step = data_offs / chip->ecc.size;
end_step = (data_offs + readlen - 1) / chip->ecc.size;
num_steps = end_step - start_step + 1;
index = start_step * chip->ecc.bytes;
/* Data size aligned to ECC ecc.size */
datafrag_len = num_steps * chip->ecc.size;
eccfrag_len = num_steps * chip->ecc.bytes;
data_col_addr = start_step * chip->ecc.size;
/* If we read not a page aligned data */
if (data_col_addr != 0)
chip->cmdfunc(mtd, NAND_CMD_RNDOUT, data_col_addr, -1);
p = bufpoi + data_col_addr;
chip->read_buf(mtd, p, datafrag_len);
/* Calculate ECC */
for (i = 0; i < eccfrag_len ; i += chip->ecc.bytes, p += chip->ecc.size)
chip->ecc.calculate(mtd, p, &chip->buffers->ecccalc[i]);
/*
* The performance is faster if we position offsets according to
* ecc.pos. Let's make sure that there are no gaps in ECC positions.
*/
ret = mtd_ooblayout_find_eccregion(mtd, index, &section, &oobregion);
if (ret)
return ret;
if (oobregion.length < eccfrag_len)
gaps = 1;
if (gaps) {
chip->cmdfunc(mtd, NAND_CMD_RNDOUT, mtd->writesize, -1);
chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
} else {
/*
* Send the command to read the particular ECC bytes take care
* about buswidth alignment in read_buf.
*/
aligned_pos = oobregion.offset & ~(busw - 1);
aligned_len = eccfrag_len;
if (oobregion.offset & (busw - 1))
aligned_len++;
if ((oobregion.offset + (num_steps * chip->ecc.bytes)) &
(busw - 1))
aligned_len++;
chip->cmdfunc(mtd, NAND_CMD_RNDOUT,
mtd->writesize + aligned_pos, -1);
chip->read_buf(mtd, &chip->oob_poi[aligned_pos], aligned_len);
}
ret = mtd_ooblayout_get_eccbytes(mtd, chip->buffers->ecccode,
chip->oob_poi, index, eccfrag_len);
if (ret)
return ret;
p = bufpoi + data_col_addr;
for (i = 0; i < eccfrag_len ; i += chip->ecc.bytes, p += chip->ecc.size) {
int stat;
stat = chip->ecc.correct(mtd, p,
&chip->buffers->ecccode[i], &chip->buffers->ecccalc[i]);
if (stat == -EBADMSG &&
(chip->ecc.options & NAND_ECC_GENERIC_ERASED_CHECK)) {
/* check for empty pages with bitflips */
stat = nand_check_erased_ecc_chunk(p, chip->ecc.size,
&chip->buffers->ecccode[i],
chip->ecc.bytes,
NULL, 0,
chip->ecc.strength);
}
if (stat < 0) {
mtd->ecc_stats.failed++;
} else {
mtd->ecc_stats.corrected += stat;
max_bitflips = max_t(unsigned int, max_bitflips, stat);
}
}
return max_bitflips;
}
/**
* nand_read_page_hwecc - [REPLACEABLE] hardware ECC based page read function
* @mtd: mtd info structure
* @chip: nand chip info structure
* @buf: buffer to store read data
* @oob_required: caller requires OOB data read to chip->oob_poi
* @page: page number to read
*
* Not for syndrome calculating ECC controllers which need a special oob layout.
*/
static int nand_read_page_hwecc(struct mtd_info *mtd, struct nand_chip *chip,
uint8_t *buf, int oob_required, int page)
{
int i, eccsize = chip->ecc.size, ret;
int eccbytes = chip->ecc.bytes;
int eccsteps = chip->ecc.steps;
uint8_t *p = buf;
uint8_t *ecc_calc = chip->buffers->ecccalc;
uint8_t *ecc_code = chip->buffers->ecccode;
unsigned int max_bitflips = 0;
for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
chip->ecc.hwctl(mtd, NAND_ECC_READ);
chip->read_buf(mtd, p, eccsize);
chip->ecc.calculate(mtd, p, &ecc_calc[i]);
}
chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
ret = mtd_ooblayout_get_eccbytes(mtd, ecc_code, chip->oob_poi, 0,
chip->ecc.total);
if (ret)
return ret;
eccsteps = chip->ecc.steps;
p = buf;
for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
int stat;
stat = chip->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]);
if (stat == -EBADMSG &&
(chip->ecc.options & NAND_ECC_GENERIC_ERASED_CHECK)) {
/* check for empty pages with bitflips */
stat = nand_check_erased_ecc_chunk(p, eccsize,
&ecc_code[i], eccbytes,
NULL, 0,
chip->ecc.strength);
}
if (stat < 0) {
mtd->ecc_stats.failed++;
} else {
mtd->ecc_stats.corrected += stat;
max_bitflips = max_t(unsigned int, max_bitflips, stat);
}
}
return max_bitflips;
}
/**
* nand_read_page_hwecc_oob_first - [REPLACEABLE] hw ecc, read oob first
* @mtd: mtd info structure
* @chip: nand chip info structure
* @buf: buffer to store read data
* @oob_required: caller requires OOB data read to chip->oob_poi
* @page: page number to read
*
* Hardware ECC for large page chips, require OOB to be read first. For this
* ECC mode, the write_page method is re-used from ECC_HW. These methods
* read/write ECC from the OOB area, unlike the ECC_HW_SYNDROME support with
* multiple ECC steps, follows the "infix ECC" scheme and reads/writes ECC from
* the data area, by overwriting the NAND manufacturer bad block markings.
*/
static int nand_read_page_hwecc_oob_first(struct mtd_info *mtd,
struct nand_chip *chip, uint8_t *buf, int oob_required, int page)
{
int i, eccsize = chip->ecc.size, ret;
int eccbytes = chip->ecc.bytes;
int eccsteps = chip->ecc.steps;
uint8_t *p = buf;
uint8_t *ecc_code = chip->buffers->ecccode;
uint8_t *ecc_calc = chip->buffers->ecccalc;
unsigned int max_bitflips = 0;
/* Read the OOB area first */
chip->cmdfunc(mtd, NAND_CMD_READOOB, 0, page);
chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
chip->cmdfunc(mtd, NAND_CMD_READ0, 0, page);
ret = mtd_ooblayout_get_eccbytes(mtd, ecc_code, chip->oob_poi, 0,
chip->ecc.total);
if (ret)
return ret;
for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
int stat;
chip->ecc.hwctl(mtd, NAND_ECC_READ);
chip->read_buf(mtd, p, eccsize);
chip->ecc.calculate(mtd, p, &ecc_calc[i]);
stat = chip->ecc.correct(mtd, p, &ecc_code[i], NULL);
if (stat == -EBADMSG &&
(chip->ecc.options & NAND_ECC_GENERIC_ERASED_CHECK)) {
/* check for empty pages with bitflips */
stat = nand_check_erased_ecc_chunk(p, eccsize,
&ecc_code[i], eccbytes,
NULL, 0,
chip->ecc.strength);
}
if (stat < 0) {
mtd->ecc_stats.failed++;
} else {
mtd->ecc_stats.corrected += stat;
max_bitflips = max_t(unsigned int, max_bitflips, stat);
}
}
return max_bitflips;
}
/**
* nand_read_page_syndrome - [REPLACEABLE] hardware ECC syndrome based page read
* @mtd: mtd info structure
* @chip: nand chip info structure
* @buf: buffer to store read data
* @oob_required: caller requires OOB data read to chip->oob_poi
* @page: page number to read
*
* The hw generator calculates the error syndrome automatically. Therefore we
* need a special oob layout and handling.
*/
static int nand_read_page_syndrome(struct mtd_info *mtd, struct nand_chip *chip,
uint8_t *buf, int oob_required, int page)
{
int i, eccsize = chip->ecc.size;
int eccbytes = chip->ecc.bytes;
int eccsteps = chip->ecc.steps;
int eccpadbytes = eccbytes + chip->ecc.prepad + chip->ecc.postpad;
uint8_t *p = buf;
uint8_t *oob = chip->oob_poi;
unsigned int max_bitflips = 0;
for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
int stat;
chip->ecc.hwctl(mtd, NAND_ECC_READ);
chip->read_buf(mtd, p, eccsize);
if (chip->ecc.prepad) {
chip->read_buf(mtd, oob, chip->ecc.prepad);
oob += chip->ecc.prepad;
}
chip->ecc.hwctl(mtd, NAND_ECC_READSYN);
chip->read_buf(mtd, oob, eccbytes);
stat = chip->ecc.correct(mtd, p, oob, NULL);
oob += eccbytes;
if (chip->ecc.postpad) {
chip->read_buf(mtd, oob, chip->ecc.postpad);
oob += chip->ecc.postpad;
}
if (stat == -EBADMSG &&
(chip->ecc.options & NAND_ECC_GENERIC_ERASED_CHECK)) {
/* check for empty pages with bitflips */
stat = nand_check_erased_ecc_chunk(p, chip->ecc.size,
oob - eccpadbytes,
eccpadbytes,
NULL, 0,
chip->ecc.strength);
}
if (stat < 0) {
mtd->ecc_stats.failed++;
} else {
mtd->ecc_stats.corrected += stat;
max_bitflips = max_t(unsigned int, max_bitflips, stat);
}
}
/* Calculate remaining oob bytes */
i = mtd->oobsize - (oob - chip->oob_poi);
if (i)
chip->read_buf(mtd, oob, i);
return max_bitflips;
}
/**
* nand_transfer_oob - [INTERN] Transfer oob to client buffer
* @mtd: mtd info structure
* @oob: oob destination address
* @ops: oob ops structure
* @len: size of oob to transfer
*/
static uint8_t *nand_transfer_oob(struct mtd_info *mtd, uint8_t *oob,
struct mtd_oob_ops *ops, size_t len)
{
struct nand_chip *chip = mtd_to_nand(mtd);
int ret;
switch (ops->mode) {
case MTD_OPS_PLACE_OOB:
case MTD_OPS_RAW:
memcpy(oob, chip->oob_poi + ops->ooboffs, len);
return oob + len;
case MTD_OPS_AUTO_OOB:
ret = mtd_ooblayout_get_databytes(mtd, oob, chip->oob_poi,
ops->ooboffs, len);
BUG_ON(ret);
return oob + len;
default:
BUG();
}
return NULL;
}
/**
* nand_setup_read_retry - [INTERN] Set the READ RETRY mode
* @mtd: MTD device structure
* @retry_mode: the retry mode to use
*
* Some vendors supply a special command to shift the Vt threshold, to be used
* when there are too many bitflips in a page (i.e., ECC error). After setting
* a new threshold, the host should retry reading the page.
*/
static int nand_setup_read_retry(struct mtd_info *mtd, int retry_mode)
{
struct nand_chip *chip = mtd_to_nand(mtd);
pr_debug("setting READ RETRY mode %d\n", retry_mode);
if (retry_mode >= chip->read_retries)
return -EINVAL;
if (!chip->setup_read_retry)
return -EOPNOTSUPP;
return chip->setup_read_retry(mtd, retry_mode);
}
/**
* nand_do_read_ops - [INTERN] Read data with ECC
* @mtd: MTD device structure
* @from: offset to read from
* @ops: oob ops structure
*
* Internal function. Called with chip held.
*/
static int nand_do_read_ops(struct mtd_info *mtd, loff_t from,
struct mtd_oob_ops *ops)
{
int chipnr, page, realpage, col, bytes, aligned, oob_required;
struct nand_chip *chip = mtd_to_nand(mtd);
int ret = 0;
uint32_t readlen = ops->len;
uint32_t oobreadlen = ops->ooblen;
uint32_t max_oobsize = mtd_oobavail(mtd, ops);
uint8_t *bufpoi, *oob, *buf;
int use_bufpoi;
unsigned int max_bitflips = 0;
int retry_mode = 0;
bool ecc_fail = false;
chipnr = (int)(from >> chip->chip_shift);
chip->select_chip(mtd, chipnr);
realpage = (int)(from >> chip->page_shift);
page = realpage & chip->pagemask;
col = (int)(from & (mtd->writesize - 1));
buf = ops->datbuf;
oob = ops->oobbuf;
oob_required = oob ? 1 : 0;
while (1) {
unsigned int ecc_failures = mtd->ecc_stats.failed;
bytes = min(mtd->writesize - col, readlen);
aligned = (bytes == mtd->writesize);
if (!aligned)
use_bufpoi = 1;
else if (chip->options & NAND_USE_BOUNCE_BUFFER)
use_bufpoi = !virt_addr_valid(buf);
else
use_bufpoi = 0;
/* Is the current page in the buffer? */
if (realpage != chip->pagebuf || oob) {
bufpoi = use_bufpoi ? chip->buffers->databuf : buf;
if (use_bufpoi && aligned)
pr_debug("%s: using read bounce buffer for buf@%p\n",
__func__, buf);
read_retry:
chip->cmdfunc(mtd, NAND_CMD_READ0, 0x00, page);
/*
* Now read the page into the buffer. Absent an error,
* the read methods return max bitflips per ecc step.
*/
if (unlikely(ops->mode == MTD_OPS_RAW))
ret = chip->ecc.read_page_raw(mtd, chip, bufpoi,
oob_required,
page);
else if (!aligned && NAND_HAS_SUBPAGE_READ(chip) &&
!oob)
ret = chip->ecc.read_subpage(mtd, chip,
col, bytes, bufpoi,
page);
else
ret = chip->ecc.read_page(mtd, chip, bufpoi,
oob_required, page);
if (ret < 0) {
if (use_bufpoi)
/* Invalidate page cache */
chip->pagebuf = -1;
break;
}
max_bitflips = max_t(unsigned int, max_bitflips, ret);
/* Transfer not aligned data */
if (use_bufpoi) {
if (!NAND_HAS_SUBPAGE_READ(chip) && !oob &&
!(mtd->ecc_stats.failed - ecc_failures) &&
(ops->mode != MTD_OPS_RAW)) {
chip->pagebuf = realpage;
chip->pagebuf_bitflips = ret;
} else {
/* Invalidate page cache */
chip->pagebuf = -1;
}
memcpy(buf, chip->buffers->databuf + col, bytes);
}
if (unlikely(oob)) {
int toread = min(oobreadlen, max_oobsize);
if (toread) {
oob = nand_transfer_oob(mtd,
oob, ops, toread);
oobreadlen -= toread;
}
}
if (chip->options & NAND_NEED_READRDY) {
/* Apply delay or wait for ready/busy pin */
if (!chip->dev_ready)
udelay(chip->chip_delay);
else
nand_wait_ready(mtd);
}
if (mtd->ecc_stats.failed - ecc_failures) {
if (retry_mode + 1 < chip->read_retries) {
retry_mode++;
ret = nand_setup_read_retry(mtd,
retry_mode);
if (ret < 0)
break;
/* Reset failures; retry */
mtd->ecc_stats.failed = ecc_failures;
goto read_retry;
} else {
/* No more retry modes; real failure */
ecc_fail = true;
}
}
buf += bytes;
} else {
memcpy(buf, chip->buffers->databuf + col, bytes);
buf += bytes;
max_bitflips = max_t(unsigned int, max_bitflips,
chip->pagebuf_bitflips);
}
readlen -= bytes;
/* Reset to retry mode 0 */
if (retry_mode) {
ret = nand_setup_read_retry(mtd, 0);
if (ret < 0)
break;
retry_mode = 0;
}
if (!readlen)
break;
/* For subsequent reads align to page boundary */
col = 0;
/* Increment page address */
realpage++;
page = realpage & chip->pagemask;
/* Check, if we cross a chip boundary */
if (!page) {
chipnr++;
chip->select_chip(mtd, -1);
chip->select_chip(mtd, chipnr);
}
}
chip->select_chip(mtd, -1);
ops->retlen = ops->len - (size_t) readlen;
if (oob)
ops->oobretlen = ops->ooblen - oobreadlen;
if (ret < 0)
return ret;
if (ecc_fail)
return -EBADMSG;
return max_bitflips;
}
/**
* nand_read - [MTD Interface] MTD compatibility 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
*
* Get hold of the chip and call nand_do_read.
*/
static int nand_read(struct mtd_info *mtd, loff_t from, size_t len,
size_t *retlen, uint8_t *buf)
{
struct mtd_oob_ops ops;
int ret;
nand_get_device(mtd, FL_READING);
memset(&ops, 0, sizeof(ops));
ops.len = len;
ops.datbuf = buf;
ops.mode = MTD_OPS_PLACE_OOB;
ret = nand_do_read_ops(mtd, from, &ops);
*retlen = ops.retlen;
nand_release_device(mtd);
return ret;
}
/**
* nand_read_oob_std - [REPLACEABLE] the most common OOB data read function
* @mtd: mtd info structure
* @chip: nand chip info structure
* @page: page number to read
*/
int nand_read_oob_std(struct mtd_info *mtd, struct nand_chip *chip, int page)
{
chip->cmdfunc(mtd, NAND_CMD_READOOB, 0, page);
chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
return 0;
}
EXPORT_SYMBOL(nand_read_oob_std);
/**
* nand_read_oob_syndrome - [REPLACEABLE] OOB data read function for HW ECC
* with syndromes
* @mtd: mtd info structure
* @chip: nand chip info structure
* @page: page number to read
*/
int nand_read_oob_syndrome(struct mtd_info *mtd, struct nand_chip *chip,
int page)
{
int length = mtd->oobsize;
int chunk = chip->ecc.bytes + chip->ecc.prepad + chip->ecc.postpad;
int eccsize = chip->ecc.size;
uint8_t *bufpoi = chip->oob_poi;
int i, toread, sndrnd = 0, pos;
chip->cmdfunc(mtd, NAND_CMD_READ0, chip->ecc.size, page);
for (i = 0; i < chip->ecc.steps; i++) {
if (sndrnd) {
pos = eccsize + i * (eccsize + chunk);
if (mtd->writesize > 512)
chip->cmdfunc(mtd, NAND_CMD_RNDOUT, pos, -1);
else
chip->cmdfunc(mtd, NAND_CMD_READ0, pos, page);
} else
sndrnd = 1;
toread = min_t(int, length, chunk);
chip->read_buf(mtd, bufpoi, toread);
bufpoi += toread;
length -= toread;
}
if (length > 0)
chip->read_buf(mtd, bufpoi, length);
return 0;
}
EXPORT_SYMBOL(nand_read_oob_syndrome);
/**
* nand_write_oob_std - [REPLACEABLE] the most common OOB data write function
* @mtd: mtd info structure
* @chip: nand chip info structure
* @page: page number to write
*/
int nand_write_oob_std(struct mtd_info *mtd, struct nand_chip *chip, int page)
{
int status = 0;
const uint8_t *buf = chip->oob_poi;
int length = mtd->oobsize;
chip->cmdfunc(mtd, NAND_CMD_SEQIN, mtd->writesize, page);
chip->write_buf(mtd, buf, length);
/* Send command to program the OOB data */
chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
status = chip->waitfunc(mtd, chip);
return status & NAND_STATUS_FAIL ? -EIO : 0;
}
EXPORT_SYMBOL(nand_write_oob_std);
/**
* nand_write_oob_syndrome - [REPLACEABLE] OOB data write function for HW ECC
* with syndrome - only for large page flash
* @mtd: mtd info structure
* @chip: nand chip info structure
* @page: page number to write
*/
int nand_write_oob_syndrome(struct mtd_info *mtd, struct nand_chip *chip,
int page)
{
int chunk = chip->ecc.bytes + chip->ecc.prepad + chip->ecc.postpad;
int eccsize = chip->ecc.size, length = mtd->oobsize;
int i, len, pos, status = 0, sndcmd = 0, steps = chip->ecc.steps;
const uint8_t *bufpoi = chip->oob_poi;
/*
* data-ecc-data-ecc ... ecc-oob
* or
* data-pad-ecc-pad-data-pad .... ecc-pad-oob
*/
if (!chip->ecc.prepad && !chip->ecc.postpad) {
pos = steps * (eccsize + chunk);
steps = 0;
} else
pos = eccsize;
chip->cmdfunc(mtd, NAND_CMD_SEQIN, pos, page);
for (i = 0; i < steps; i++) {
if (sndcmd) {
if (mtd->writesize <= 512) {
uint32_t fill = 0xFFFFFFFF;
len = eccsize;
while (len > 0) {
int num = min_t(int, len, 4);
chip->write_buf(mtd, (uint8_t *)&fill,
num);
len -= num;
}
} else {
pos = eccsize + i * (eccsize + chunk);
chip->cmdfunc(mtd, NAND_CMD_RNDIN, pos, -1);
}
} else
sndcmd = 1;
len = min_t(int, length, chunk);
chip->write_buf(mtd, bufpoi, len);
bufpoi += len;
length -= len;
}
if (length > 0)
chip->write_buf(mtd, bufpoi, length);
chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
status = chip->waitfunc(mtd, chip);
return status & NAND_STATUS_FAIL ? -EIO : 0;
}
EXPORT_SYMBOL(nand_write_oob_syndrome);
/**
* nand_do_read_oob - [INTERN] NAND read out-of-band
* @mtd: MTD device structure
* @from: offset to read from
* @ops: oob operations description structure
*
* NAND read out-of-band data from the spare area.
*/
static int nand_do_read_oob(struct mtd_info *mtd, loff_t from,
struct mtd_oob_ops *ops)
{
int page, realpage, chipnr;
struct nand_chip *chip = mtd_to_nand(mtd);
struct mtd_ecc_stats stats;
int readlen = ops->ooblen;
int len;
uint8_t *buf = ops->oobbuf;
int ret = 0;
pr_debug("%s: from = 0x%08Lx, len = %i\n",
__func__, (unsigned long long)from, readlen);
stats = mtd->ecc_stats;
len = mtd_oobavail(mtd, ops);
if (unlikely(ops->ooboffs >= len)) {
pr_debug("%s: attempt to start read outside oob\n",
__func__);
return -EINVAL;
}
/* Do not allow reads past end of device */
if (unlikely(from >= mtd->size ||
ops->ooboffs + readlen > ((mtd->size >> chip->page_shift) -
(from >> chip->page_shift)) * len)) {
pr_debug("%s: attempt to read beyond end of device\n",
__func__);
return -EINVAL;
}
chipnr = (int)(from >> chip->chip_shift);
chip->select_chip(mtd, chipnr);
/* Shift to get page */
realpage = (int)(from >> chip->page_shift);
page = realpage & chip->pagemask;
while (1) {
if (ops->mode == MTD_OPS_RAW)
ret = chip->ecc.read_oob_raw(mtd, chip, page);
else
ret = chip->ecc.read_oob(mtd, chip, page);
if (ret < 0)
break;
len = min(len, readlen);
buf = nand_transfer_oob(mtd, buf, ops, len);
if (chip->options & NAND_NEED_READRDY) {
/* Apply delay or wait for ready/busy pin */
if (!chip->dev_ready)
udelay(chip->chip_delay);
else
nand_wait_ready(mtd);
}
readlen -= len;
if (!readlen)
break;
/* Increment page address */
realpage++;
page = realpage & chip->pagemask;
/* Check, if we cross a chip boundary */
if (!page) {
chipnr++;
chip->select_chip(mtd, -1);
chip->select_chip(mtd, chipnr);
}
}
chip->select_chip(mtd, -1);
ops->oobretlen = ops->ooblen - readlen;
if (ret < 0)
return ret;
if (mtd->ecc_stats.failed - stats.failed)
return -EBADMSG;
return mtd->ecc_stats.corrected - stats.corrected ? -EUCLEAN : 0;
}
/**
* nand_read_oob - [MTD Interface] NAND read data and/or out-of-band
* @mtd: MTD device structure
* @from: offset to read from
* @ops: oob operation description structure
*
* NAND read data and/or out-of-band data.
*/
static int nand_read_oob(struct mtd_info *mtd, loff_t from,
struct mtd_oob_ops *ops)
{
int ret;
ops->retlen = 0;
/* Do not allow reads past end of device */
if (ops->datbuf && (from + ops->len) > mtd->size) {
pr_debug("%s: attempt to read beyond end of device\n",
__func__);
return -EINVAL;
}
if (ops->mode != MTD_OPS_PLACE_OOB &&
ops->mode != MTD_OPS_AUTO_OOB &&
ops->mode != MTD_OPS_RAW)
return -ENOTSUPP;
nand_get_device(mtd, FL_READING);
if (!ops->datbuf)
ret = nand_do_read_oob(mtd, from, ops);
else
ret = nand_do_read_ops(mtd, from, ops);
nand_release_device(mtd);
return ret;
}
/**
* nand_write_page_raw - [INTERN] raw page write function
* @mtd: mtd info structure
* @chip: nand chip info structure
* @buf: data buffer
* @oob_required: must write chip->oob_poi to OOB
* @page: page number to write
*
* Not for syndrome calculating ECC controllers, which use a special oob layout.
*/
static int nand_write_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
const uint8_t *buf, int oob_required, int page)
{
chip->write_buf(mtd, buf, mtd->writesize);
if (oob_required)
chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
return 0;
}
/**
* nand_write_page_raw_syndrome - [INTERN] raw page write function
* @mtd: mtd info structure
* @chip: nand chip info structure
* @buf: data buffer
* @oob_required: must write chip->oob_poi to OOB
* @page: page number to write
*
* We need a special oob layout and handling even when ECC isn't checked.
*/
static int nand_write_page_raw_syndrome(struct mtd_info *mtd,
struct nand_chip *chip,
const uint8_t *buf, int oob_required,
int page)
{
int eccsize = chip->ecc.size;
int eccbytes = chip->ecc.bytes;
uint8_t *oob = chip->oob_poi;
int steps, size;
for (steps = chip->ecc.steps; steps > 0; steps--) {
chip->write_buf(mtd, buf, eccsize);
buf += eccsize;
if (chip->ecc.prepad) {
chip->write_buf(mtd, oob, chip->ecc.prepad);
oob += chip->ecc.prepad;
}
chip->write_buf(mtd, oob, eccbytes);
oob += eccbytes;
if (chip->ecc.postpad) {
chip->write_buf(mtd, oob, chip->ecc.postpad);
oob += chip->ecc.postpad;
}
}
size = mtd->oobsize - (oob - chip->oob_poi);
if (size)
chip->write_buf(mtd, oob, size);
return 0;
}
/**
* nand_write_page_swecc - [REPLACEABLE] software ECC based page write function
* @mtd: mtd info structure
* @chip: nand chip info structure
* @buf: data buffer
* @oob_required: must write chip->oob_poi to OOB
* @page: page number to write
*/
static int nand_write_page_swecc(struct mtd_info *mtd, struct nand_chip *chip,
const uint8_t *buf, int oob_required,
int page)
{
int i, eccsize = chip->ecc.size, ret;
int eccbytes = chip->ecc.bytes;
int eccsteps = chip->ecc.steps;
uint8_t *ecc_calc = chip->buffers->ecccalc;
const uint8_t *p = buf;
/* Software ECC calculation */
for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize)
chip->ecc.calculate(mtd, p, &ecc_calc[i]);
ret = mtd_ooblayout_set_eccbytes(mtd, ecc_calc, chip->oob_poi, 0,
chip->ecc.total);
if (ret)
return ret;
return chip->ecc.write_page_raw(mtd, chip, buf, 1, page);
}
/**
* nand_write_page_hwecc - [REPLACEABLE] hardware ECC based page write function
* @mtd: mtd info structure
* @chip: nand chip info structure
* @buf: data buffer
* @oob_required: must write chip->oob_poi to OOB
* @page: page number to write
*/
static int nand_write_page_hwecc(struct mtd_info *mtd, struct nand_chip *chip,
const uint8_t *buf, int oob_required,
int page)
{
int i, eccsize = chip->ecc.size, ret;
int eccbytes = chip->ecc.bytes;
int eccsteps = chip->ecc.steps;
uint8_t *ecc_calc = chip->buffers->ecccalc;
const uint8_t *p = buf;
for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
chip->ecc.hwctl(mtd, NAND_ECC_WRITE);
chip->write_buf(mtd, p, eccsize);
chip->ecc.calculate(mtd, p, &ecc_calc[i]);
}
ret = mtd_ooblayout_set_eccbytes(mtd, ecc_calc, chip->oob_poi, 0,
chip->ecc.total);
if (ret)
return ret;
chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
return 0;
}
/**
* nand_write_subpage_hwecc - [REPLACEABLE] hardware ECC based subpage write
* @mtd: mtd info structure
* @chip: nand chip info structure
* @offset: column address of subpage within the page
* @data_len: data length
* @buf: data buffer
* @oob_required: must write chip->oob_poi to OOB
* @page: page number to write
*/
static int nand_write_subpage_hwecc(struct mtd_info *mtd,
struct nand_chip *chip, uint32_t offset,
uint32_t data_len, const uint8_t *buf,
int oob_required, int page)
{
uint8_t *oob_buf = chip->oob_poi;
uint8_t *ecc_calc = chip->buffers->ecccalc;
int ecc_size = chip->ecc.size;
int ecc_bytes = chip->ecc.bytes;
int ecc_steps = chip->ecc.steps;
uint32_t start_step = offset / ecc_size;
uint32_t end_step = (offset + data_len - 1) / ecc_size;
int oob_bytes = mtd->oobsize / ecc_steps;
int step, ret;
for (step = 0; step < ecc_steps; step++) {
/* configure controller for WRITE access */
chip->ecc.hwctl(mtd, NAND_ECC_WRITE);
/* write data (untouched subpages already masked by 0xFF) */
chip->write_buf(mtd, buf, ecc_size);
/* mask ECC of un-touched subpages by padding 0xFF */
if ((step < start_step) || (step > end_step))
memset(ecc_calc, 0xff, ecc_bytes);
else
chip->ecc.calculate(mtd, buf, ecc_calc);
/* mask OOB of un-touched subpages by padding 0xFF */
/* if oob_required, preserve OOB metadata of written subpage */
if (!oob_required || (step < start_step) || (step > end_step))
memset(oob_buf, 0xff, oob_bytes);
buf += ecc_size;
ecc_calc += ecc_bytes;
oob_buf += oob_bytes;
}
/* copy calculated ECC for whole page to chip->buffer->oob */
/* this include masked-value(0xFF) for unwritten subpages */
ecc_calc = chip->buffers->ecccalc;
ret = mtd_ooblayout_set_eccbytes(mtd, ecc_calc, chip->oob_poi, 0,
chip->ecc.total);
if (ret)
return ret;
/* write OOB buffer to NAND device */
chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
return 0;
}
/**
* nand_write_page_syndrome - [REPLACEABLE] hardware ECC syndrome based page write
* @mtd: mtd info structure
* @chip: nand chip info structure
* @buf: data buffer
* @oob_required: must write chip->oob_poi to OOB
* @page: page number to write
*
* The hw generator calculates the error syndrome automatically. Therefore we
* need a special oob layout and handling.
*/
static int nand_write_page_syndrome(struct mtd_info *mtd,
struct nand_chip *chip,
const uint8_t *buf, int oob_required,
int page)
{
int i, eccsize = chip->ecc.size;
int eccbytes = chip->ecc.bytes;
int eccsteps = chip->ecc.steps;
const uint8_t *p = buf;
uint8_t *oob = chip->oob_poi;
for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
chip->ecc.hwctl(mtd, NAND_ECC_WRITE);
chip->write_buf(mtd, p, eccsize);
if (chip->ecc.prepad) {
chip->write_buf(mtd, oob, chip->ecc.prepad);
oob += chip->ecc.prepad;
}
chip->ecc.calculate(mtd, p, oob);
chip->write_buf(mtd, oob, eccbytes);
oob += eccbytes;
if (chip->ecc.postpad) {
chip->write_buf(mtd, oob, chip->ecc.postpad);
oob += chip->ecc.postpad;
}
}
/* Calculate remaining oob bytes */
i = mtd->oobsize - (oob - chip->oob_poi);
if (i)
chip->write_buf(mtd, oob, i);
return 0;
}
/**
* nand_write_page - [REPLACEABLE] write one page
* @mtd: MTD device structure
* @chip: NAND chip descriptor
* @offset: address offset within the page
* @data_len: length of actual data to be written
* @buf: the data to write
* @oob_required: must write chip->oob_poi to OOB
* @page: page number to write
* @cached: cached programming
* @raw: use _raw version of write_page
*/
static int nand_write_page(struct mtd_info *mtd, struct nand_chip *chip,
uint32_t offset, int data_len, const uint8_t *buf,
int oob_required, int page, int cached, int raw)
{
int status, subpage;
if (!(chip->options & NAND_NO_SUBPAGE_WRITE) &&
chip->ecc.write_subpage)
subpage = offset || (data_len < mtd->writesize);
else
subpage = 0;
chip->cmdfunc(mtd, NAND_CMD_SEQIN, 0x00, page);
if (unlikely(raw))
status = chip->ecc.write_page_raw(mtd, chip, buf,
oob_required, page);
else if (subpage)
status = chip->ecc.write_subpage(mtd, chip, offset, data_len,
buf, oob_required, page);
else
status = chip->ecc.write_page(mtd, chip, buf, oob_required,
page);
if (status < 0)
return status;
/*
* Cached progamming disabled for now. Not sure if it's worth the
* trouble. The speed gain is not very impressive. (2.3->2.6Mib/s).
*/
cached = 0;
if (!cached || !NAND_HAS_CACHEPROG(chip)) {
chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
status = chip->waitfunc(mtd, chip);
/*
* See if operation failed and additional status checks are
* available.
*/
if ((status & NAND_STATUS_FAIL) && (chip->errstat))
status = chip->errstat(mtd, chip, FL_WRITING, status,
page);
if (status & NAND_STATUS_FAIL)
return -EIO;
} else {
chip->cmdfunc(mtd, NAND_CMD_CACHEDPROG, -1, -1);
status = chip->waitfunc(mtd, chip);
}
return 0;
}
/**
* nand_fill_oob - [INTERN] Transfer client buffer to oob
* @mtd: MTD device structure
* @oob: oob data buffer
* @len: oob data write length
* @ops: oob ops structure
*/
static uint8_t *nand_fill_oob(struct mtd_info *mtd, uint8_t *oob, size_t len,
struct mtd_oob_ops *ops)
{
struct nand_chip *chip = mtd_to_nand(mtd);
int ret;
/*
* Initialise to all 0xFF, to avoid the possibility of left over OOB
* data from a previous OOB read.
*/
memset(chip->oob_poi, 0xff, mtd->oobsize);
switch (ops->mode) {
case MTD_OPS_PLACE_OOB:
case MTD_OPS_RAW:
memcpy(chip->oob_poi + ops->ooboffs, oob, len);
return oob + len;
case MTD_OPS_AUTO_OOB:
ret = mtd_ooblayout_set_databytes(mtd, oob, chip->oob_poi,
ops->ooboffs, len);
BUG_ON(ret);
return oob + len;
default:
BUG();
}
return NULL;
}
#define NOTALIGNED(x) ((x & (chip->subpagesize - 1)) != 0)
/**
* nand_do_write_ops - [INTERN] NAND write with ECC
* @mtd: MTD device structure
* @to: offset to write to
* @ops: oob operations description structure
*
* NAND write with ECC.
*/
static int nand_do_write_ops(struct mtd_info *mtd, loff_t to,
struct mtd_oob_ops *ops)
{
int chipnr, realpage, page, blockmask, column;
struct nand_chip *chip = mtd_to_nand(mtd);
uint32_t writelen = ops->len;
uint32_t oobwritelen = ops->ooblen;
uint32_t oobmaxlen = mtd_oobavail(mtd, ops);
uint8_t *oob = ops->oobbuf;
uint8_t *buf = ops->datbuf;
int ret;
int oob_required = oob ? 1 : 0;
ops->retlen = 0;
if (!writelen)
return 0;
/* Reject writes, which are not page aligned */
if (NOTALIGNED(to) || NOTALIGNED(ops->len)) {
pr_notice("%s: attempt to write non page aligned data\n",
__func__);
return -EINVAL;
}
column = to & (mtd->writesize - 1);
chipnr = (int)(to >> chip->chip_shift);
chip->select_chip(mtd, chipnr);
/* Check, if it is write protected */
if (nand_check_wp(mtd)) {
ret = -EIO;
goto err_out;
}
realpage = (int)(to >> chip->page_shift);
page = realpage & chip->pagemask;
blockmask = (1 << (chip->phys_erase_shift - chip->page_shift)) - 1;
/* Invalidate the page cache, when we write to the cached page */
if (to <= ((loff_t)chip->pagebuf << chip->page_shift) &&
((loff_t)chip->pagebuf << chip->page_shift) < (to + ops->len))
chip->pagebuf = -1;
/* Don't allow multipage oob writes with offset */
if (oob && ops->ooboffs && (ops->ooboffs + ops->ooblen > oobmaxlen)) {
ret = -EINVAL;
goto err_out;
}
while (1) {
int bytes = mtd->writesize;
int cached = writelen > bytes && page != blockmask;
uint8_t *wbuf = buf;
int use_bufpoi;
int part_pagewr = (column || writelen < mtd->writesize);
if (part_pagewr)
use_bufpoi = 1;
else if (chip->options & NAND_USE_BOUNCE_BUFFER)
use_bufpoi = !virt_addr_valid(buf);
else
use_bufpoi = 0;
/* Partial page write?, or need to use bounce buffer */
if (use_bufpoi) {
pr_debug("%s: using write bounce buffer for buf@%p\n",
__func__, buf);
cached = 0;
if (part_pagewr)
bytes = min_t(int, bytes - column, writelen);
chip->pagebuf = -1;
memset(chip->buffers->databuf, 0xff, mtd->writesize);
memcpy(&chip->buffers->databuf[column], buf, bytes);
wbuf = chip->buffers->databuf;
}
if (unlikely(oob)) {
size_t len = min(oobwritelen, oobmaxlen);
oob = nand_fill_oob(mtd, oob, len, ops);
oobwritelen -= len;
} else {
/* We still need to erase leftover OOB data */
memset(chip->oob_poi, 0xff, mtd->oobsize);
}
ret = chip->write_page(mtd, chip, column, bytes, wbuf,
oob_required, page, cached,
(ops->mode == MTD_OPS_RAW));
if (ret)
break;
writelen -= bytes;
if (!writelen)
break;
column = 0;
buf += bytes;
realpage++;
page = realpage & chip->pagemask;
/* Check, if we cross a chip boundary */
if (!page) {
chipnr++;
chip->select_chip(mtd, -1);
chip->select_chip(mtd, chipnr);
}
}
ops->retlen = ops->len - writelen;
if (unlikely(oob))
ops->oobretlen = ops->ooblen;
err_out:
chip->select_chip(mtd, -1);
return ret;
}
/**
* panic_nand_write - [MTD Interface] NAND write with ECC
* @mtd: MTD device structure
* @to: offset to write to
* @len: number of bytes to write
* @retlen: pointer to variable to store the number of written bytes
* @buf: the data to write
*
* NAND write with ECC. Used when performing writes in interrupt context, this
* may for example be called by mtdoops when writing an oops while in panic.
*/
static int panic_nand_write(struct mtd_info *mtd, loff_t to, size_t len,
size_t *retlen, const uint8_t *buf)
{
struct nand_chip *chip = mtd_to_nand(mtd);
struct mtd_oob_ops ops;
int ret;
/* Wait for the device to get ready */
panic_nand_wait(mtd, chip, 400);
/* Grab the device */
panic_nand_get_device(chip, mtd, FL_WRITING);
memset(&ops, 0, sizeof(ops));
ops.len = len;
ops.datbuf = (uint8_t *)buf;
ops.mode = MTD_OPS_PLACE_OOB;
ret = nand_do_write_ops(mtd, to, &ops);
*retlen = ops.retlen;
return ret;
}
/**
* nand_write - [MTD Interface] NAND write with ECC
* @mtd: MTD device structure
* @to: offset to write to
* @len: number of bytes to write
* @retlen: pointer to variable to store the number of written bytes
* @buf: the data to write
*
* NAND write with ECC.
*/
static int nand_write(struct mtd_info *mtd, loff_t to, size_t len,
size_t *retlen, const uint8_t *buf)
{
struct mtd_oob_ops ops;
int ret;
nand_get_device(mtd, FL_WRITING);
memset(&ops, 0, sizeof(ops));
ops.len = len;
ops.datbuf = (uint8_t *)buf;
ops.mode = MTD_OPS_PLACE_OOB;
ret = nand_do_write_ops(mtd, to, &ops);
*retlen = ops.retlen;
nand_release_device(mtd);
return ret;
}
/**
* nand_do_write_oob - [MTD Interface] NAND write out-of-band
* @mtd: MTD device structure
* @to: offset to write to
* @ops: oob operation description structure
*
* NAND write out-of-band.
*/
static int nand_do_write_oob(struct mtd_info *mtd, loff_t to,
struct mtd_oob_ops *ops)
{
int chipnr, page, status, len;
struct nand_chip *chip = mtd_to_nand(mtd);
pr_debug("%s: to = 0x%08x, len = %i\n",
__func__, (unsigned int)to, (int)ops->ooblen);
len = mtd_oobavail(mtd, ops);
/* Do not allow write past end of page */
if ((ops->ooboffs + ops->ooblen) > len) {
pr_debug("%s: attempt to write past end of page\n",
__func__);
return -EINVAL;
}
if (unlikely(ops->ooboffs >= len)) {
pr_debug("%s: attempt to start write outside oob\n",
__func__);
return -EINVAL;
}
/* Do not allow write past end of device */
if (unlikely(to >= mtd->size ||
ops->ooboffs + ops->ooblen >
((mtd->size >> chip->page_shift) -
(to >> chip->page_shift)) * len)) {
pr_debug("%s: attempt to write beyond end of device\n",
__func__);
return -EINVAL;
}
chipnr = (int)(to >> chip->chip_shift);
chip->select_chip(mtd, chipnr);
/* Shift to get page */
page = (int)(to >> chip->page_shift);
/*
* Reset the chip. Some chips (like the Toshiba TC5832DC found in one
* of my DiskOnChip 2000 test units) will clear the whole data page too
* if we don't do this. I have no clue why, but I seem to have 'fixed'
* it in the doc2000 driver in August 1999. dwmw2.
*/
nand_reset(chip);
/* Check, if it is write protected */
if (nand_check_wp(mtd)) {
chip->select_chip(mtd, -1);
return -EROFS;
}
/* Invalidate the page cache, if we write to the cached page */
if (page == chip->pagebuf)
chip->pagebuf = -1;
nand_fill_oob(mtd, ops->oobbuf, ops->ooblen, ops);
if (ops->mode == MTD_OPS_RAW)
status = chip->ecc.write_oob_raw(mtd, chip, page & chip->pagemask);
else
status = chip->ecc.write_oob(mtd, chip, page & chip->pagemask);
chip->select_chip(mtd, -1);
if (status)
return status;
ops->oobretlen = ops->ooblen;
return 0;
}
/**
* nand_write_oob - [MTD Interface] NAND write data and/or out-of-band
* @mtd: MTD device structure
* @to: offset to write to
* @ops: oob operation description structure
*/
static int nand_write_oob(struct mtd_info *mtd, loff_t to,
struct mtd_oob_ops *ops)
{
int ret = -ENOTSUPP;
ops->retlen = 0;
/* Do not allow writes past end of device */
if (ops->datbuf && (to + ops->len) > mtd->size) {
pr_debug("%s: attempt to write beyond end of device\n",
__func__);
return -EINVAL;
}
nand_get_device(mtd, FL_WRITING);
switch (ops->mode) {
case MTD_OPS_PLACE_OOB:
case MTD_OPS_AUTO_OOB:
case MTD_OPS_RAW:
break;
default:
goto out;
}
if (!ops->datbuf)
ret = nand_do_write_oob(mtd, to, ops);
else
ret = nand_do_write_ops(mtd, to, ops);
out:
nand_release_device(mtd);
return ret;
}
/**
* single_erase - [GENERIC] NAND standard block erase command function
* @mtd: MTD device structure
* @page: the page address of the block which will be erased
*
* Standard erase command for NAND chips. Returns NAND status.
*/
static int single_erase(struct mtd_info *mtd, int page)
{
struct nand_chip *chip = mtd_to_nand(mtd);
/* Send commands to erase a block */
chip->cmdfunc(mtd, NAND_CMD_ERASE1, -1, page);
chip->cmdfunc(mtd, NAND_CMD_ERASE2, -1, -1);
return chip->waitfunc(mtd, chip);
}
/**
* nand_erase - [MTD Interface] erase block(s)
* @mtd: MTD device structure
* @instr: erase instruction
*
* Erase one ore more blocks.
*/
static int nand_erase(struct mtd_info *mtd, struct erase_info *instr)
{
return nand_erase_nand(mtd, instr, 0);
}
/**
* nand_erase_nand - [INTERN] erase block(s)
* @mtd: MTD device structure
* @instr: erase instruction
* @allowbbt: allow erasing the bbt area
*
* Erase one ore more blocks.
*/
int nand_erase_nand(struct mtd_info *mtd, struct erase_info *instr,
int allowbbt)
{
int page, status, pages_per_block, ret, chipnr;
struct nand_chip *chip = mtd_to_nand(mtd);
loff_t len;
pr_debug("%s: start = 0x%012llx, len = %llu\n",
__func__, (unsigned long long)instr->addr,
(unsigned long long)instr->len);
if (check_offs_len(mtd, instr->addr, instr->len))
return -EINVAL;
/* Grab the lock and see if the device is available */
nand_get_device(mtd, FL_ERASING);
/* Shift to get first page */
page = (int)(instr->addr >> chip->page_shift);
chipnr = (int)(instr->addr >> chip->chip_shift);
/* Calculate pages in each block */
pages_per_block = 1 << (chip->phys_erase_shift - chip->page_shift);
/* Select the NAND device */
chip->select_chip(mtd, chipnr);
/* Check, if it is write protected */
if (nand_check_wp(mtd)) {
pr_debug("%s: device is write protected!\n",
__func__);
instr->state = MTD_ERASE_FAILED;
goto erase_exit;
}
/* Loop through the pages */
len = instr->len;
instr->state = MTD_ERASING;
while (len) {
/* Check if we have a bad block, we do not erase bad blocks! */
if (nand_block_checkbad(mtd, ((loff_t) page) <<
chip->page_shift, allowbbt)) {
pr_warn("%s: attempt to erase a bad block at page 0x%08x\n",
__func__, page);
instr->state = MTD_ERASE_FAILED;
goto erase_exit;
}
/*
* Invalidate the page cache, if we erase the block which
* contains the current cached page.
*/
if (page <= chip->pagebuf && chip->pagebuf <
(page + pages_per_block))
chip->pagebuf = -1;
status = chip->erase(mtd, page & chip->pagemask);
/*
* See if operation failed and additional status checks are
* available
*/
if ((status & NAND_STATUS_FAIL) && (chip->errstat))
status = chip->errstat(mtd, chip, FL_ERASING,
status, page);
/* See if block erase succeeded */
if (status & NAND_STATUS_FAIL) {
pr_debug("%s: failed erase, page 0x%08x\n",
__func__, page);
instr->state = MTD_ERASE_FAILED;
instr->fail_addr =
((loff_t)page << chip->page_shift);
goto erase_exit;
}
/* Increment page address and decrement length */
len -= (1ULL << chip->phys_erase_shift);
page += pages_per_block;
/* Check, if we cross a chip boundary */
if (len && !(page & chip->pagemask)) {
chipnr++;
chip->select_chip(mtd, -1);
chip->select_chip(mtd, chipnr);
}
}
instr->state = MTD_ERASE_DONE;
erase_exit:
ret = instr->state == MTD_ERASE_DONE ? 0 : -EIO;
/* Deselect and wake up anyone waiting on the device */
chip->select_chip(mtd, -1);
nand_release_device(mtd);
/* Do call back function */
if (!ret)
mtd_erase_callback(instr);
/* Return more or less happy */
return ret;
}
/**
* nand_sync - [MTD Interface] sync
* @mtd: MTD device structure
*
* Sync is actually a wait for chip ready function.
*/
static void nand_sync(struct mtd_info *mtd)
{
pr_debug("%s: called\n", __func__);
/* Grab the lock and see if the device is available */
nand_get_device(mtd, FL_SYNCING);
/* Release it and go back */
nand_release_device(mtd);
}
/**
* nand_block_isbad - [MTD Interface] Check if block at offset is bad
* @mtd: MTD device structure
* @offs: offset relative to mtd start
*/
static int nand_block_isbad(struct mtd_info *mtd, loff_t offs)
{
struct nand_chip *chip = mtd_to_nand(mtd);
int chipnr = (int)(offs >> chip->chip_shift);
int ret;
/* Select the NAND device */
nand_get_device(mtd, FL_READING);
chip->select_chip(mtd, chipnr);
ret = nand_block_checkbad(mtd, offs, 0);
chip->select_chip(mtd, -1);
nand_release_device(mtd);
return ret;
}
/**
* nand_block_markbad - [MTD Interface] Mark block at the given offset as bad
* @mtd: MTD device structure
* @ofs: offset relative to mtd start
*/
static int nand_block_markbad(struct mtd_info *mtd, loff_t ofs)
{
int ret;
ret = nand_block_isbad(mtd, ofs);
if (ret) {
/* If it was bad already, return success and do nothing */
if (ret > 0)
return 0;
return ret;
}
return nand_block_markbad_lowlevel(mtd, ofs);
}
/**
* nand_onfi_set_features- [REPLACEABLE] set features for ONFI nand
* @mtd: MTD device structure
* @chip: nand chip info structure
* @addr: feature address.
* @subfeature_param: the subfeature parameters, a four bytes array.
*/
static int nand_onfi_set_features(struct mtd_info *mtd, struct nand_chip *chip,
int addr, uint8_t *subfeature_param)
{
int status;
int i;
if (!chip->onfi_version ||
!(le16_to_cpu(chip->onfi_params.opt_cmd)
& ONFI_OPT_CMD_SET_GET_FEATURES))
return -EINVAL;
chip->cmdfunc(mtd, NAND_CMD_SET_FEATURES, addr, -1);
for (i = 0; i < ONFI_SUBFEATURE_PARAM_LEN; ++i)
chip->write_byte(mtd, subfeature_param[i]);
status = chip->waitfunc(mtd, chip);
if (status & NAND_STATUS_FAIL)
return -EIO;
return 0;
}
/**
* nand_onfi_get_features- [REPLACEABLE] get features for ONFI nand
* @mtd: MTD device structure
* @chip: nand chip info structure
* @addr: feature address.
* @subfeature_param: the subfeature parameters, a four bytes array.
*/
static int nand_onfi_get_features(struct mtd_info *mtd, struct nand_chip *chip,
int addr, uint8_t *subfeature_param)
{
int i;
if (!chip->onfi_version ||
!(le16_to_cpu(chip->onfi_params.opt_cmd)
& ONFI_OPT_CMD_SET_GET_FEATURES))
return -EINVAL;
chip->cmdfunc(mtd, NAND_CMD_GET_FEATURES, addr, -1);
for (i = 0; i < ONFI_SUBFEATURE_PARAM_LEN; ++i)
*subfeature_param++ = chip->read_byte(mtd);
return 0;
}
/**
* nand_suspend - [MTD Interface] Suspend the NAND flash
* @mtd: MTD device structure
*/
static int nand_suspend(struct mtd_info *mtd)
{
return nand_get_device(mtd, FL_PM_SUSPENDED);
}
/**
* nand_resume - [MTD Interface] Resume the NAND flash
* @mtd: MTD device structure
*/
static void nand_resume(struct mtd_info *mtd)
{
struct nand_chip *chip = mtd_to_nand(mtd);
if (chip->state == FL_PM_SUSPENDED)
nand_release_device(mtd);
else
pr_err("%s called for a chip which is not in suspended state\n",
__func__);
}
/**
* nand_shutdown - [MTD Interface] Finish the current NAND operation and
* prevent further operations
* @mtd: MTD device structure
*/
static void nand_shutdown(struct mtd_info *mtd)
{
nand_get_device(mtd, FL_PM_SUSPENDED);
}
/* Set default functions */
static void nand_set_defaults(struct nand_chip *chip, int busw)
{
/* check for proper chip_delay setup, set 20us if not */
if (!chip->chip_delay)
chip->chip_delay = 20;
/* check, if a user supplied command function given */
if (chip->cmdfunc == NULL)
chip->cmdfunc = nand_command;
/* check, if a user supplied wait function given */
if (chip->waitfunc == NULL)
chip->waitfunc = nand_wait;
if (!chip->select_chip)
chip->select_chip = nand_select_chip;
/* set for ONFI nand */
if (!chip->onfi_set_features)
chip->onfi_set_features = nand_onfi_set_features;
if (!chip->onfi_get_features)
chip->onfi_get_features = nand_onfi_get_features;
/* If called twice, pointers that depend on busw may need to be reset */
if (!chip->read_byte || chip->read_byte == nand_read_byte)
chip->read_byte = busw ? nand_read_byte16 : nand_read_byte;
if (!chip->read_word)
chip->read_word = nand_read_word;
if (!chip->block_bad)
chip->block_bad = nand_block_bad;
if (!chip->block_markbad)
chip->block_markbad = nand_default_block_markbad;
if (!chip->write_buf || chip->write_buf == nand_write_buf)
chip->write_buf = busw ? nand_write_buf16 : nand_write_buf;
if (!chip->write_byte || chip->write_byte == nand_write_byte)
chip->write_byte = busw ? nand_write_byte16 : nand_write_byte;
if (!chip->read_buf || chip->read_buf == nand_read_buf)
chip->read_buf = busw ? nand_read_buf16 : nand_read_buf;
if (!chip->scan_bbt)
chip->scan_bbt = nand_default_bbt;
if (!chip->controller) {
chip->controller = &chip->hwcontrol;
nand_hw_control_init(chip->controller);
}
}
/* Sanitize ONFI strings so we can safely print them */
static void sanitize_string(uint8_t *s, size_t len)
{
ssize_t i;
/* Null terminate */
s[len - 1] = 0;
/* Remove non printable chars */
for (i = 0; i < len - 1; i++) {
if (s[i] < ' ' || s[i] > 127)
s[i] = '?';
}
/* Remove trailing spaces */
strim(s);
}
static u16 onfi_crc16(u16 crc, u8 const *p, size_t len)
{
int i;
while (len--) {
crc ^= *p++ << 8;
for (i = 0; i < 8; i++)
crc = (crc << 1) ^ ((crc & 0x8000) ? 0x8005 : 0);
}
return crc;
}
/* Parse the Extended Parameter Page. */
static int nand_flash_detect_ext_param_page(struct mtd_info *mtd,
struct nand_chip *chip, struct nand_onfi_params *p)
{
struct onfi_ext_param_page *ep;
struct onfi_ext_section *s;
struct onfi_ext_ecc_info *ecc;
uint8_t *cursor;
int ret = -EINVAL;
int len;
int i;
len = le16_to_cpu(p->ext_param_page_length) * 16;
ep = kmalloc(len, GFP_KERNEL);
if (!ep)
return -ENOMEM;
/* Send our own NAND_CMD_PARAM. */
chip->cmdfunc(mtd, NAND_CMD_PARAM, 0, -1);
/* Use the Change Read Column command to skip the ONFI param pages. */
chip->cmdfunc(mtd, NAND_CMD_RNDOUT,
sizeof(*p) * p->num_of_param_pages , -1);
/* Read out the Extended Parameter Page. */
chip->read_buf(mtd, (uint8_t *)ep, len);
if ((onfi_crc16(ONFI_CRC_BASE, ((uint8_t *)ep) + 2, len - 2)
!= le16_to_cpu(ep->crc))) {
pr_debug("fail in the CRC.\n");
goto ext_out;
}
/*
* Check the signature.
* Do not strictly follow the ONFI spec, maybe changed in future.
*/
if (strncmp(ep->sig, "EPPS", 4)) {
pr_debug("The signature is invalid.\n");
goto ext_out;
}
/* find the ECC section. */
cursor = (uint8_t *)(ep + 1);
for (i = 0; i < ONFI_EXT_SECTION_MAX; i++) {
s = ep->sections + i;
if (s->type == ONFI_SECTION_TYPE_2)
break;
cursor += s->length * 16;
}
if (i == ONFI_EXT_SECTION_MAX) {
pr_debug("We can not find the ECC section.\n");
goto ext_out;
}
/* get the info we want. */
ecc = (struct onfi_ext_ecc_info *)cursor;
if (!ecc->codeword_size) {
pr_debug("Invalid codeword size\n");
goto ext_out;
}
chip->ecc_strength_ds = ecc->ecc_bits;
chip->ecc_step_ds = 1 << ecc->codeword_size;
ret = 0;
ext_out:
kfree(ep);
return ret;
}
static int nand_setup_read_retry_micron(struct mtd_info *mtd, int retry_mode)
{
struct nand_chip *chip = mtd_to_nand(mtd);
uint8_t feature[ONFI_SUBFEATURE_PARAM_LEN] = {retry_mode};
return chip->onfi_set_features(mtd, chip, ONFI_FEATURE_ADDR_READ_RETRY,
feature);
}
/*
* Configure chip properties from Micron vendor-specific ONFI table
*/
static void nand_onfi_detect_micron(struct nand_chip *chip,
struct nand_onfi_params *p)
{
struct nand_onfi_vendor_micron *micron = (void *)p->vendor;
if (le16_to_cpu(p->vendor_revision) < 1)
return;
chip->read_retries = micron->read_retry_options;
chip->setup_read_retry = nand_setup_read_retry_micron;
}
/*
* Check if the NAND chip is ONFI compliant, returns 1 if it is, 0 otherwise.
*/
static int nand_flash_detect_onfi(struct mtd_info *mtd, struct nand_chip *chip,
int *busw)
{
struct nand_onfi_params *p = &chip->onfi_params;
int i, j;
int val;
/* Try ONFI for unknown chip or LP */
chip->cmdfunc(mtd, NAND_CMD_READID, 0x20, -1);
if (chip->read_byte(mtd) != 'O' || chip->read_byte(mtd) != 'N' ||
chip->read_byte(mtd) != 'F' || chip->read_byte(mtd) != 'I')
return 0;
chip->cmdfunc(mtd, NAND_CMD_PARAM, 0, -1);
for (i = 0; i < 3; i++) {
for (j = 0; j < sizeof(*p); j++)
((uint8_t *)p)[j] = chip->read_byte(mtd);
if (onfi_crc16(ONFI_CRC_BASE, (uint8_t *)p, 254) ==
le16_to_cpu(p->crc)) {
break;
}
}
if (i == 3) {
pr_err("Could not find valid ONFI parameter page; aborting\n");
return 0;
}
/* Check version */
val = le16_to_cpu(p->revision);
if (val & (1 << 5))
chip->onfi_version = 23;
else if (val & (1 << 4))
chip->onfi_version = 22;
else if (val & (1 << 3))
chip->onfi_version = 21;
else if (val & (1 << 2))
chip->onfi_version = 20;
else if (val & (1 << 1))
chip->onfi_version = 10;
if (!chip->onfi_version) {
pr_info("unsupported ONFI version: %d\n", val);
return 0;
}
sanitize_string(p->manufacturer, sizeof(p->manufacturer));
sanitize_string(p->model, sizeof(p->model));
if (!mtd->name)
mtd->name = p->model;
mtd->writesize = le32_to_cpu(p->byte_per_page);
/*
* pages_per_block and blocks_per_lun may not be a power-of-2 size
* (don't ask me who thought of this...). MTD assumes that these
* dimensions will be power-of-2, so just truncate the remaining area.
*/
mtd->erasesize = 1 << (fls(le32_to_cpu(p->pages_per_block)) - 1);
mtd->erasesize *= mtd->writesize;
mtd->oobsize = le16_to_cpu(p->spare_bytes_per_page);
/* See erasesize comment */
chip->chipsize = 1 << (fls(le32_to_cpu(p->blocks_per_lun)) - 1);
chip->chipsize *= (uint64_t)mtd->erasesize * p->lun_count;
chip->bits_per_cell = p->bits_per_cell;
if (onfi_feature(chip) & ONFI_FEATURE_16_BIT_BUS)
*busw = NAND_BUSWIDTH_16;
else
*busw = 0;
if (p->ecc_bits != 0xff) {
chip->ecc_strength_ds = p->ecc_bits;
chip->ecc_step_ds = 512;
} else if (chip->onfi_version >= 21 &&
(onfi_feature(chip) & ONFI_FEATURE_EXT_PARAM_PAGE)) {
/*
* The nand_flash_detect_ext_param_page() uses the
* Change Read Column command which maybe not supported
* by the chip->cmdfunc. So try to update the chip->cmdfunc
* now. We do not replace user supplied command function.
*/
if (mtd->writesize > 512 && chip->cmdfunc == nand_command)
chip->cmdfunc = nand_command_lp;
/* The Extended Parameter Page is supported since ONFI 2.1. */
if (nand_flash_detect_ext_param_page(mtd, chip, p))
pr_warn("Failed to detect ONFI extended param page\n");
} else {
pr_warn("Could not retrieve ONFI ECC requirements\n");
}
if (p->jedec_id == NAND_MFR_MICRON)
nand_onfi_detect_micron(chip, p);
return 1;
}
/*
* Check if the NAND chip is JEDEC compliant, returns 1 if it is, 0 otherwise.
*/
static int nand_flash_detect_jedec(struct mtd_info *mtd, struct nand_chip *chip,
int *busw)
{
struct nand_jedec_params *p = &chip->jedec_params;
struct jedec_ecc_info *ecc;
int val;
int i, j;
/* Try JEDEC for unknown chip or LP */
chip->cmdfunc(mtd, NAND_CMD_READID, 0x40, -1);
if (chip->read_byte(mtd) != 'J' || chip->read_byte(mtd) != 'E' ||
chip->read_byte(mtd) != 'D' || chip->read_byte(mtd) != 'E' ||
chip->read_byte(mtd) != 'C')
return 0;
chip->cmdfunc(mtd, NAND_CMD_PARAM, 0x40, -1);
for (i = 0; i < 3; i++) {
for (j = 0; j < sizeof(*p); j++)
((uint8_t *)p)[j] = chip->read_byte(mtd);
if (onfi_crc16(ONFI_CRC_BASE, (uint8_t *)p, 510) ==
le16_to_cpu(p->crc))
break;
}
if (i == 3) {
pr_err("Could not find valid JEDEC parameter page; aborting\n");
return 0;
}
/* Check version */
val = le16_to_cpu(p->revision);
if (val & (1 << 2))
chip->jedec_version = 10;
else if (val & (1 << 1))
chip->jedec_version = 1; /* vendor specific version */
if (!chip->jedec_version) {
pr_info("unsupported JEDEC version: %d\n", val);
return 0;
}
sanitize_string(p->manufacturer, sizeof(p->manufacturer));
sanitize_string(p->model, sizeof(p->model));
if (!mtd->name)
mtd->name = p->model;
mtd->writesize = le32_to_cpu(p->byte_per_page);
/* Please reference to the comment for nand_flash_detect_onfi. */
mtd->erasesize = 1 << (fls(le32_to_cpu(p->pages_per_block)) - 1);
mtd->erasesize *= mtd->writesize;
mtd->oobsize = le16_to_cpu(p->spare_bytes_per_page);
/* Please reference to the comment for nand_flash_detect_onfi. */
chip->chipsize = 1 << (fls(le32_to_cpu(p->blocks_per_lun)) - 1);
chip->chipsize *= (uint64_t)mtd->erasesize * p->lun_count;
chip->bits_per_cell = p->bits_per_cell;
if (jedec_feature(chip) & JEDEC_FEATURE_16_BIT_BUS)
*busw = NAND_BUSWIDTH_16;
else
*busw = 0;
/* ECC info */
ecc = &p->ecc_info[0];
if (ecc->codeword_size >= 9) {
chip->ecc_strength_ds = ecc->ecc_bits;
chip->ecc_step_ds = 1 << ecc->codeword_size;
} else {
pr_warn("Invalid codeword size\n");
}
return 1;
}
/*
* nand_id_has_period - Check if an ID string has a given wraparound period
* @id_data: the ID string
* @arrlen: the length of the @id_data array
* @period: the period of repitition
*
* Check if an ID string is repeated within a given sequence of bytes at
* specific repetition interval period (e.g., {0x20,0x01,0x7F,0x20} has a
* period of 3). This is a helper function for nand_id_len(). Returns non-zero
* if the repetition has a period of @period; otherwise, returns zero.
*/
static int nand_id_has_period(u8 *id_data, int arrlen, int period)
{
int i, j;
for (i = 0; i < period; i++)
for (j = i + period; j < arrlen; j += period)
if (id_data[i] != id_data[j])
return 0;
return 1;
}
/*
* nand_id_len - Get the length of an ID string returned by CMD_READID
* @id_data: the ID string
* @arrlen: the length of the @id_data array
* Returns the length of the ID string, according to known wraparound/trailing
* zero patterns. If no pattern exists, returns the length of the array.
*/
static int nand_id_len(u8 *id_data, int arrlen)
{
int last_nonzero, period;
/* Find last non-zero byte */
for (last_nonzero = arrlen - 1; last_nonzero >= 0; last_nonzero--)
if (id_data[last_nonzero])
break;
/* All zeros */
if (last_nonzero < 0)
return 0;
/* Calculate wraparound period */
for (period = 1; period < arrlen; period++)
if (nand_id_has_period(id_data, arrlen, period))
break;
/* There's a repeated pattern */
if (period < arrlen)
return period;
/* There are trailing zeros */
if (last_nonzero < arrlen - 1)
return last_nonzero + 1;
/* No pattern detected */
return arrlen;
}
/* Extract the bits of per cell from the 3rd byte of the extended ID */
static int nand_get_bits_per_cell(u8 cellinfo)
{
int bits;
bits = cellinfo & NAND_CI_CELLTYPE_MSK;
bits >>= NAND_CI_CELLTYPE_SHIFT;
return bits + 1;
}
/*
* Many new NAND share similar device ID codes, which represent the size of the
* chip. The rest of the parameters must be decoded according to generic or
* manufacturer-specific "extended ID" decoding patterns.
*/
static void nand_decode_ext_id(struct mtd_info *mtd, struct nand_chip *chip,
u8 id_data[8], int *busw)
{
int extid, id_len;
/* The 3rd id byte holds MLC / multichip data */
chip->bits_per_cell = nand_get_bits_per_cell(id_data[2]);
/* The 4th id byte is the important one */
extid = id_data[3];
id_len = nand_id_len(id_data, 8);
/*
* Field definitions are in the following datasheets:
* Old style (4,5 byte ID): Samsung K9GAG08U0M (p.32)
* New Samsung (6 byte ID): Samsung K9GAG08U0F (p.44)
* Hynix MLC (6 byte ID): Hynix H27UBG8T2B (p.22)
*
* Check for ID length, non-zero 6th byte, cell type, and Hynix/Samsung
* ID to decide what to do.
*/
if (id_len == 6 && id_data[0] == NAND_MFR_SAMSUNG &&
!nand_is_slc(chip) && id_data[5] != 0x00) {
/* Calc pagesize */
mtd->writesize = 2048 << (extid & 0x03);
extid >>= 2;
/* Calc oobsize */
switch (((extid >> 2) & 0x04) | (extid & 0x03)) {
case 1:
mtd->oobsize = 128;
break;
case 2:
mtd->oobsize = 218;
break;
case 3:
mtd->oobsize = 400;
break;
case 4:
mtd->oobsize = 436;
break;
case 5:
mtd->oobsize = 512;
break;
case 6:
mtd->oobsize = 640;
break;
case 7:
default: /* Other cases are "reserved" (unknown) */
mtd->oobsize = 1024;
break;
}
extid >>= 2;
/* Calc blocksize */
mtd->erasesize = (128 * 1024) <<
(((extid >> 1) & 0x04) | (extid & 0x03));
*busw = 0;
} else if (id_len == 6 && id_data[0] == NAND_MFR_HYNIX &&
!nand_is_slc(chip)) {
unsigned int tmp;
/* Calc pagesize */
mtd->writesize = 2048 << (extid & 0x03);
extid >>= 2;
/* Calc oobsize */
switch (((extid >> 2) & 0x04) | (extid & 0x03)) {
case 0:
mtd->oobsize = 128;
break;
case 1:
mtd->oobsize = 224;
break;
case 2:
mtd->oobsize = 448;
break;
case 3:
mtd->oobsize = 64;
break;
case 4:
mtd->oobsize = 32;
break;
case 5:
mtd->oobsize = 16;
break;
default:
mtd->oobsize = 640;
break;
}
extid >>= 2;
/* Calc blocksize */
tmp = ((extid >> 1) & 0x04) | (extid & 0x03);
if (tmp < 0x03)
mtd->erasesize = (128 * 1024) << tmp;
else if (tmp == 0x03)
mtd->erasesize = 768 * 1024;
else
mtd->erasesize = (64 * 1024) << tmp;
*busw = 0;
} else {
/* Calc pagesize */
mtd->writesize = 1024 << (extid & 0x03);
extid >>= 2;
/* Calc oobsize */
mtd->oobsize = (8 << (extid & 0x01)) *
(mtd->writesize >> 9);
extid >>= 2;
/* Calc blocksize. Blocksize is multiples of 64KiB */
mtd->erasesize = (64 * 1024) << (extid & 0x03);
extid >>= 2;
/* Get buswidth information */
*busw = (extid & 0x01) ? NAND_BUSWIDTH_16 : 0;
/*
* Toshiba 24nm raw SLC (i.e., not BENAND) have 32B OOB per
* 512B page. For Toshiba SLC, we decode the 5th/6th byte as
* follows:
* - ID byte 6, bits[2:0]: 100b -> 43nm, 101b -> 32nm,
* 110b -> 24nm
* - ID byte 5, bit[7]: 1 -> BENAND, 0 -> raw SLC
*/
if (id_len >= 6 && id_data[0] == NAND_MFR_TOSHIBA &&
nand_is_slc(chip) &&
(id_data[5] & 0x7) == 0x6 /* 24nm */ &&
!(id_data[4] & 0x80) /* !BENAND */) {
mtd->oobsize = 32 * mtd->writesize >> 9;
}
}
}
/*
* Old devices have chip data hardcoded in the device ID table. nand_decode_id
* decodes a matching ID table entry and assigns the MTD size parameters for
* the chip.
*/
static void nand_decode_id(struct mtd_info *mtd, struct nand_chip *chip,
struct nand_flash_dev *type, u8 id_data[8],
int *busw)
{
int maf_id = id_data[0];
mtd->erasesize = type->erasesize;
mtd->writesize = type->pagesize;
mtd->oobsize = mtd->writesize / 32;
*busw = type->options & NAND_BUSWIDTH_16;
/* All legacy ID NAND are small-page, SLC */
chip->bits_per_cell = 1;
/*
* Check for Spansion/AMD ID + repeating 5th, 6th byte since
* some Spansion chips have erasesize that conflicts with size
* listed in nand_ids table.
* Data sheet (5 byte ID): Spansion S30ML-P ORNAND (p.39)
*/
if (maf_id == NAND_MFR_AMD && id_data[4] != 0x00 && id_data[5] == 0x00
&& id_data[6] == 0x00 && id_data[7] == 0x00
&& mtd->writesize == 512) {
mtd->erasesize = 128 * 1024;
mtd->erasesize <<= ((id_data[3] & 0x03) << 1);
}
}
/*
* Set the bad block marker/indicator (BBM/BBI) patterns according to some
* heuristic patterns using various detected parameters (e.g., manufacturer,
* page size, cell-type information).
*/
static void nand_decode_bbm_options(struct mtd_info *mtd,
struct nand_chip *chip, u8 id_data[8])
{
int maf_id = id_data[0];
/* Set the bad block position */
if (mtd->writesize > 512 || (chip->options & NAND_BUSWIDTH_16))
chip->badblockpos = NAND_LARGE_BADBLOCK_POS;
else
chip->badblockpos = NAND_SMALL_BADBLOCK_POS;
/*
* Bad block marker is stored in the last page of each block on Samsung
* and Hynix MLC devices; stored in first two pages of each block on
* Micron devices with 2KiB pages and on SLC Samsung, Hynix, Toshiba,
* AMD/Spansion, and Macronix. All others scan only the first page.
*/
if (!nand_is_slc(chip) &&
(maf_id == NAND_MFR_SAMSUNG ||
maf_id == NAND_MFR_HYNIX))
chip->bbt_options |= NAND_BBT_SCANLASTPAGE;
else if ((nand_is_slc(chip) &&
(maf_id == NAND_MFR_SAMSUNG ||
maf_id == NAND_MFR_HYNIX ||
maf_id == NAND_MFR_TOSHIBA ||
maf_id == NAND_MFR_AMD ||
maf_id == NAND_MFR_MACRONIX)) ||
(mtd->writesize == 2048 &&
maf_id == NAND_MFR_MICRON))
chip->bbt_options |= NAND_BBT_SCAN2NDPAGE;
}
static inline bool is_full_id_nand(struct nand_flash_dev *type)
{
return type->id_len;
}
static bool find_full_id_nand(struct mtd_info *mtd, struct nand_chip *chip,
struct nand_flash_dev *type, u8 *id_data, int *busw)
{
if (!strncmp(type->id, id_data, type->id_len)) {
mtd->writesize = type->pagesize;
mtd->erasesize = type->erasesize;
mtd->oobsize = type->oobsize;
chip->bits_per_cell = nand_get_bits_per_cell(id_data[2]);
chip->chipsize = (uint64_t)type->chipsize << 20;
chip->options |= type->options;
chip->ecc_strength_ds = NAND_ECC_STRENGTH(type);
chip->ecc_step_ds = NAND_ECC_STEP(type);
chip->onfi_timing_mode_default =
type->onfi_timing_mode_default;
*busw = type->options & NAND_BUSWIDTH_16;
if (!mtd->name)
mtd->name = type->name;
return true;
}
return false;
}
/*
* Get the flash and manufacturer id and lookup if the type is supported.
*/
static struct nand_flash_dev *nand_get_flash_type(struct mtd_info *mtd,
struct nand_chip *chip,
int *maf_id, int *dev_id,
struct nand_flash_dev *type)
{
int busw;
int i, maf_idx;
u8 id_data[8];
/* Select the device */
chip->select_chip(mtd, 0);
/*
* Reset the chip, required by some chips (e.g. Micron MT29FxGxxxxx)
* after power-up.
*/
nand_reset(chip);
/* Send the command for reading device ID */
chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
/* Read manufacturer and device IDs */
*maf_id = chip->read_byte(mtd);
*dev_id = chip->read_byte(mtd);
/*
* Try again to make sure, as some systems the bus-hold or other
* interface concerns can cause random data which looks like a
* possibly credible NAND flash to appear. If the two results do
* not match, ignore the device completely.
*/
chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
/* Read entire ID string */
for (i = 0; i < 8; i++)
id_data[i] = chip->read_byte(mtd);
if (id_data[0] != *maf_id || id_data[1] != *dev_id) {
pr_info("second ID read did not match %02x,%02x against %02x,%02x\n",
*maf_id, *dev_id, id_data[0], id_data[1]);
return ERR_PTR(-ENODEV);
}
if (!type)
type = nand_flash_ids;
for (; type->name != NULL; type++) {
if (is_full_id_nand(type)) {
if (find_full_id_nand(mtd, chip, type, id_data, &busw))
goto ident_done;
} else if (*dev_id == type->dev_id) {
break;
}
}
chip->onfi_version = 0;
if (!type->name || !type->pagesize) {
/* Check if the chip is ONFI compliant */
if (nand_flash_detect_onfi(mtd, chip, &busw))
goto ident_done;
/* Check if the chip is JEDEC compliant */
if (nand_flash_detect_jedec(mtd, chip, &busw))
goto ident_done;
}
if (!type->name)
return ERR_PTR(-ENODEV);
if (!mtd->name)
mtd->name = type->name;
chip->chipsize = (uint64_t)type->chipsize << 20;
if (!type->pagesize) {
/* Decode parameters from extended ID */
nand_decode_ext_id(mtd, chip, id_data, &busw);
} else {
nand_decode_id(mtd, chip, type, id_data, &busw);
}
/* Get chip options */
chip->options |= type->options;
/*
* Check if chip is not a Samsung device. Do not clear the
* options for chips which do not have an extended id.
*/
if (*maf_id != NAND_MFR_SAMSUNG && !type->pagesize)
chip->options &= ~NAND_SAMSUNG_LP_OPTIONS;
ident_done:
/* Try to identify manufacturer */
for (maf_idx = 0; nand_manuf_ids[maf_idx].id != 0x0; maf_idx++) {
if (nand_manuf_ids[maf_idx].id == *maf_id)
break;
}
if (chip->options & NAND_BUSWIDTH_AUTO) {
WARN_ON(chip->options & NAND_BUSWIDTH_16);
chip->options |= busw;
nand_set_defaults(chip, busw);
} else if (busw != (chip->options & NAND_BUSWIDTH_16)) {
/*
* Check, if buswidth is correct. Hardware drivers should set
* chip correct!
*/
pr_info("device found, Manufacturer ID: 0x%02x, Chip ID: 0x%02x\n",
*maf_id, *dev_id);
pr_info("%s %s\n", nand_manuf_ids[maf_idx].name, mtd->name);
pr_warn("bus width %d instead %d bit\n",
(chip->options & NAND_BUSWIDTH_16) ? 16 : 8,
busw ? 16 : 8);
return ERR_PTR(-EINVAL);
}
nand_decode_bbm_options(mtd, chip, id_data);
/* Calculate the address shift from the page size */
chip->page_shift = ffs(mtd->writesize) - 1;
/* Convert chipsize to number of pages per chip -1 */
chip->pagemask = (chip->chipsize >> chip->page_shift) - 1;
chip->bbt_erase_shift = chip->phys_erase_shift =
ffs(mtd->erasesize) - 1;
if (chip->chipsize & 0xffffffff)
chip->chip_shift = ffs((unsigned)chip->chipsize) - 1;
else {
chip->chip_shift = ffs((unsigned)(chip->chipsize >> 32));
chip->chip_shift += 32 - 1;
}
chip->badblockbits = 8;
chip->erase = single_erase;
/* Do not replace user supplied command function! */
if (mtd->writesize > 512 && chip->cmdfunc == nand_command)
chip->cmdfunc = nand_command_lp;
pr_info("device found, Manufacturer ID: 0x%02x, Chip ID: 0x%02x\n",
*maf_id, *dev_id);
if (chip->onfi_version)
pr_info("%s %s\n", nand_manuf_ids[maf_idx].name,
chip->onfi_params.model);
else if (chip->jedec_version)
pr_info("%s %s\n", nand_manuf_ids[maf_idx].name,
chip->jedec_params.model);
else
pr_info("%s %s\n", nand_manuf_ids[maf_idx].name,
type->name);
pr_info("%d MiB, %s, erase size: %d KiB, page size: %d, OOB size: %d\n",
(int)(chip->chipsize >> 20), nand_is_slc(chip) ? "SLC" : "MLC",
mtd->erasesize >> 10, mtd->writesize, mtd->oobsize);
return type;
}
static const char * const nand_ecc_modes[] = {
[NAND_ECC_NONE] = "none",
[NAND_ECC_SOFT] = "soft",
[NAND_ECC_HW] = "hw",
[NAND_ECC_HW_SYNDROME] = "hw_syndrome",
[NAND_ECC_HW_OOB_FIRST] = "hw_oob_first",
};
static int of_get_nand_ecc_mode(struct device_node *np)
{
const char *pm;
int err, i;
err = of_property_read_string(np, "nand-ecc-mode", &pm);
if (err < 0)
return err;
for (i = 0; i < ARRAY_SIZE(nand_ecc_modes); i++)
if (!strcasecmp(pm, nand_ecc_modes[i]))
return i;
/*
* For backward compatibility we support few obsoleted values that don't
* have their mappings into nand_ecc_modes_t anymore (they were merged
* with other enums).
*/
if (!strcasecmp(pm, "soft_bch"))
return NAND_ECC_SOFT;
return -ENODEV;
}
static const char * const nand_ecc_algos[] = {
[NAND_ECC_HAMMING] = "hamming",
[NAND_ECC_BCH] = "bch",
};
static int of_get_nand_ecc_algo(struct device_node *np)
{
const char *pm;
int err, i;
err = of_property_read_string(np, "nand-ecc-algo", &pm);
if (!err) {
for (i = NAND_ECC_HAMMING; i < ARRAY_SIZE(nand_ecc_algos); i++)
if (!strcasecmp(pm, nand_ecc_algos[i]))
return i;
return -ENODEV;
}
/*
* For backward compatibility we also read "nand-ecc-mode" checking
* for some obsoleted values that were specifying ECC algorithm.
*/
err = of_property_read_string(np, "nand-ecc-mode", &pm);
if (err < 0)
return err;
if (!strcasecmp(pm, "soft"))
return NAND_ECC_HAMMING;
else if (!strcasecmp(pm, "soft_bch"))
return NAND_ECC_BCH;
return -ENODEV;
}
static int of_get_nand_ecc_step_size(struct device_node *np)
{
int ret;
u32 val;
ret = of_property_read_u32(np, "nand-ecc-step-size", &val);
return ret ? ret : val;
}
static int of_get_nand_ecc_strength(struct device_node *np)
{
int ret;
u32 val;
ret = of_property_read_u32(np, "nand-ecc-strength", &val);
return ret ? ret : val;
}
static int of_get_nand_bus_width(struct device_node *np)
{
u32 val;
if (of_property_read_u32(np, "nand-bus-width", &val))
return 8;
switch (val) {
case 8:
case 16:
return val;
default:
return -EIO;
}
}
static bool of_get_nand_on_flash_bbt(struct device_node *np)
{
return of_property_read_bool(np, "nand-on-flash-bbt");
}
static int nand_dt_init(struct nand_chip *chip)
{
struct device_node *dn = nand_get_flash_node(chip);
int ecc_mode, ecc_algo, ecc_strength, ecc_step;
if (!dn)
return 0;
if (of_get_nand_bus_width(dn) == 16)
chip->options |= NAND_BUSWIDTH_16;
if (of_get_nand_on_flash_bbt(dn))
chip->bbt_options |= NAND_BBT_USE_FLASH;
ecc_mode = of_get_nand_ecc_mode(dn);
ecc_algo = of_get_nand_ecc_algo(dn);
ecc_strength = of_get_nand_ecc_strength(dn);
ecc_step = of_get_nand_ecc_step_size(dn);
if ((ecc_step >= 0 && !(ecc_strength >= 0)) ||
(!(ecc_step >= 0) && ecc_strength >= 0)) {
pr_err("must set both strength and step size in DT\n");
return -EINVAL;
}
if (ecc_mode >= 0)
chip->ecc.mode = ecc_mode;
if (ecc_algo >= 0)
chip->ecc.algo = ecc_algo;
if (ecc_strength >= 0)
chip->ecc.strength = ecc_strength;
if (ecc_step > 0)
chip->ecc.size = ecc_step;
if (of_property_read_bool(dn, "nand-ecc-maximize"))
chip->ecc.options |= NAND_ECC_MAXIMIZE;
return 0;
}
/**
* nand_scan_ident - [NAND Interface] Scan for the NAND device
* @mtd: MTD device structure
* @maxchips: number of chips to scan for
* @table: alternative NAND ID table
*
* This is the first phase of the normal nand_scan() function. It reads the
* flash ID and sets up MTD fields accordingly.
*
*/
int nand_scan_ident(struct mtd_info *mtd, int maxchips,
struct nand_flash_dev *table)
{
int i, nand_maf_id, nand_dev_id;
struct nand_chip *chip = mtd_to_nand(mtd);
struct nand_flash_dev *type;
int ret;
ret = nand_dt_init(chip);
if (ret)
return ret;
if (!mtd->name && mtd->dev.parent)
mtd->name = dev_name(mtd->dev.parent);
if ((!chip->cmdfunc || !chip->select_chip) && !chip->cmd_ctrl) {
/*
* Default functions assigned for chip_select() and
* cmdfunc() both expect cmd_ctrl() to be populated,
* so we need to check that that's the case
*/
pr_err("chip.cmd_ctrl() callback is not provided");
return -EINVAL;
}
/* Set the default functions */
nand_set_defaults(chip, chip->options & NAND_BUSWIDTH_16);
/* Read the flash type */
type = nand_get_flash_type(mtd, chip, &nand_maf_id,
&nand_dev_id, table);
if (IS_ERR(type)) {
if (!(chip->options & NAND_SCAN_SILENT_NODEV))
pr_warn("No NAND device found\n");
chip->select_chip(mtd, -1);
return PTR_ERR(type);
}
ret = nand_init_data_interface(chip);
if (ret)
return ret;
chip->select_chip(mtd, -1);
/* Check for a chip array */
for (i = 1; i < maxchips; i++) {
chip->select_chip(mtd, i);
/* See comment in nand_get_flash_type for reset */
nand_reset(chip);
/* Send the command for reading device ID */
chip->cmdfunc(mtd, NAND_CMD_READID, 0x00, -1);
/* Read manufacturer and device IDs */
if (nand_maf_id != chip->read_byte(mtd) ||
nand_dev_id != chip->read_byte(mtd)) {
chip->select_chip(mtd, -1);
break;
}
chip->select_chip(mtd, -1);
}
if (i > 1)
pr_info("%d chips detected\n", i);
/* Store the number of chips and calc total size for mtd */
chip->numchips = i;
mtd->size = i * chip->chipsize;
return 0;
}
EXPORT_SYMBOL(nand_scan_ident);
static int nand_set_ecc_soft_ops(struct mtd_info *mtd)
{
struct nand_chip *chip = mtd_to_nand(mtd);
struct nand_ecc_ctrl *ecc = &chip->ecc;
if (WARN_ON(ecc->mode != NAND_ECC_SOFT))
return -EINVAL;
switch (ecc->algo) {
case NAND_ECC_HAMMING:
ecc->calculate = nand_calculate_ecc;
ecc->correct = nand_correct_data;
ecc->read_page = nand_read_page_swecc;
ecc->read_subpage = nand_read_subpage;
ecc->write_page = nand_write_page_swecc;
ecc->read_page_raw = nand_read_page_raw;
ecc->write_page_raw = nand_write_page_raw;
ecc->read_oob = nand_read_oob_std;
ecc->write_oob = nand_write_oob_std;
if (!ecc->size)
ecc->size = 256;
ecc->bytes = 3;
ecc->strength = 1;
return 0;
case NAND_ECC_BCH:
if (!mtd_nand_has_bch()) {
WARN(1, "CONFIG_MTD_NAND_ECC_BCH not enabled\n");
return -EINVAL;
}
ecc->calculate = nand_bch_calculate_ecc;
ecc->correct = nand_bch_correct_data;
ecc->read_page = nand_read_page_swecc;
ecc->read_subpage = nand_read_subpage;
ecc->write_page = nand_write_page_swecc;
ecc->read_page_raw = nand_read_page_raw;
ecc->write_page_raw = nand_write_page_raw;
ecc->read_oob = nand_read_oob_std;
ecc->write_oob = nand_write_oob_std;
/*
* Board driver should supply ecc.size and ecc.strength
* values to select how many bits are correctable.
* Otherwise, default to 4 bits for large page devices.
*/
if (!ecc->size && (mtd->oobsize >= 64)) {
ecc->size = 512;
ecc->strength = 4;
}
/*
* if no ecc placement scheme was provided pickup the default
* large page one.
*/
if (!mtd->ooblayout) {
/* handle large page devices only */
if (mtd->oobsize < 64) {
WARN(1, "OOB layout is required when using software BCH on small pages\n");
return -EINVAL;
}
mtd_set_ooblayout(mtd, &nand_ooblayout_lp_ops);
}
/* See nand_bch_init() for details. */
ecc->bytes = 0;
ecc->priv = nand_bch_init(mtd);
if (!ecc->priv) {
WARN(1, "BCH ECC initialization failed!\n");
return -EINVAL;
}
return 0;
default:
WARN(1, "Unsupported ECC algorithm!\n");
return -EINVAL;
}
}
/*
* Check if the chip configuration meet the datasheet requirements.
* If our configuration corrects A bits per B bytes and the minimum
* required correction level is X bits per Y bytes, then we must ensure
* both of the following are true:
*
* (1) A / B >= X / Y
* (2) A >= X
*
* Requirement (1) ensures we can correct for the required bitflip density.
* Requirement (2) ensures we can correct even when all bitflips are clumped
* in the same sector.
*/
static bool nand_ecc_strength_good(struct mtd_info *mtd)
{
struct nand_chip *chip = mtd_to_nand(mtd);
struct nand_ecc_ctrl *ecc = &chip->ecc;
int corr, ds_corr;
if (ecc->size == 0 || chip->ecc_step_ds == 0)
/* Not enough information */
return true;
/*
* We get the number of corrected bits per page to compare
* the correction density.
*/
corr = (mtd->writesize * ecc->strength) / ecc->size;
ds_corr = (mtd->writesize * chip->ecc_strength_ds) / chip->ecc_step_ds;
return corr >= ds_corr && ecc->strength >= chip->ecc_strength_ds;
}
/**
* nand_scan_tail - [NAND Interface] Scan for the NAND device
* @mtd: MTD device structure
*
* This is the second phase of the normal nand_scan() function. It fills out
* all the uninitialized function pointers with the defaults and scans for a
* bad block table if appropriate.
*/
int nand_scan_tail(struct mtd_info *mtd)
{
struct nand_chip *chip = mtd_to_nand(mtd);
struct nand_ecc_ctrl *ecc = &chip->ecc;
struct nand_buffers *nbuf;
int ret;
/* New bad blocks should be marked in OOB, flash-based BBT, or both */
if (WARN_ON((chip->bbt_options & NAND_BBT_NO_OOB_BBM) &&
!(chip->bbt_options & NAND_BBT_USE_FLASH)))
return -EINVAL;
if (!(chip->options & NAND_OWN_BUFFERS)) {
nbuf = kzalloc(sizeof(*nbuf) + mtd->writesize
+ mtd->oobsize * 3, GFP_KERNEL);
if (!nbuf)
return -ENOMEM;
nbuf->ecccalc = (uint8_t *)(nbuf + 1);
nbuf->ecccode = nbuf->ecccalc + mtd->oobsize;
nbuf->databuf = nbuf->ecccode + mtd->oobsize;
chip->buffers = nbuf;
} else {
if (!chip->buffers)
return -ENOMEM;
}
/* Set the internal oob buffer location, just after the page data */
chip->oob_poi = chip->buffers->databuf + mtd->writesize;
/*
* If no default placement scheme is given, select an appropriate one.
*/
if (!mtd->ooblayout &&
!(ecc->mode == NAND_ECC_SOFT && ecc->algo == NAND_ECC_BCH)) {
switch (mtd->oobsize) {
case 8:
case 16:
mtd_set_ooblayout(mtd, &nand_ooblayout_sp_ops);
break;
case 64:
case 128:
mtd_set_ooblayout(mtd, &nand_ooblayout_lp_ops);
break;
default:
WARN(1, "No oob scheme defined for oobsize %d\n",
mtd->oobsize);
ret = -EINVAL;
goto err_free;
}
}
if (!chip->write_page)
chip->write_page = nand_write_page;
/*
* Check ECC mode, default to software if 3byte/512byte hardware ECC is
* selected and we have 256 byte pagesize fallback to software ECC
*/
switch (ecc->mode) {
case NAND_ECC_HW_OOB_FIRST:
/* Similar to NAND_ECC_HW, but a separate read_page handle */
if (!ecc->calculate || !ecc->correct || !ecc->hwctl) {
WARN(1, "No ECC functions supplied; hardware ECC not possible\n");
ret = -EINVAL;
goto err_free;
}
if (!ecc->read_page)
ecc->read_page = nand_read_page_hwecc_oob_first;
case NAND_ECC_HW:
/* Use standard hwecc read page function? */
if (!ecc->read_page)
ecc->read_page = nand_read_page_hwecc;
if (!ecc->write_page)
ecc->write_page = nand_write_page_hwecc;
if (!ecc->read_page_raw)
ecc->read_page_raw = nand_read_page_raw;
if (!ecc->write_page_raw)
ecc->write_page_raw = nand_write_page_raw;
if (!ecc->read_oob)
ecc->read_oob = nand_read_oob_std;
if (!ecc->write_oob)
ecc->write_oob = nand_write_oob_std;
if (!ecc->read_subpage)
ecc->read_subpage = nand_read_subpage;
if (!ecc->write_subpage && ecc->hwctl && ecc->calculate)
ecc->write_subpage = nand_write_subpage_hwecc;
case NAND_ECC_HW_SYNDROME:
if ((!ecc->calculate || !ecc->correct || !ecc->hwctl) &&
(!ecc->read_page ||
ecc->read_page == nand_read_page_hwecc ||
!ecc->write_page ||
ecc->write_page == nand_write_page_hwecc)) {
WARN(1, "No ECC functions supplied; hardware ECC not possible\n");
ret = -EINVAL;
goto err_free;
}
/* Use standard syndrome read/write page function? */
if (!ecc->read_page)
ecc->read_page = nand_read_page_syndrome;
if (!ecc->write_page)
ecc->write_page = nand_write_page_syndrome;
if (!ecc->read_page_raw)
ecc->read_page_raw = nand_read_page_raw_syndrome;
if (!ecc->write_page_raw)
ecc->write_page_raw = nand_write_page_raw_syndrome;
if (!ecc->read_oob)
ecc->read_oob = nand_read_oob_syndrome;
if (!ecc->write_oob)
ecc->write_oob = nand_write_oob_syndrome;
if (mtd->writesize >= ecc->size) {
if (!ecc->strength) {
WARN(1, "Driver must set ecc.strength when using hardware ECC\n");
ret = -EINVAL;
goto err_free;
}
break;
}
pr_warn("%d byte HW ECC not possible on %d byte page size, fallback to SW ECC\n",
ecc->size, mtd->writesize);
ecc->mode = NAND_ECC_SOFT;
ecc->algo = NAND_ECC_HAMMING;
case NAND_ECC_SOFT:
ret = nand_set_ecc_soft_ops(mtd);
if (ret) {
ret = -EINVAL;
goto err_free;
}
break;
case NAND_ECC_NONE:
pr_warn("NAND_ECC_NONE selected by board driver. This is not recommended!\n");
ecc->read_page = nand_read_page_raw;
ecc->write_page = nand_write_page_raw;
ecc->read_oob = nand_read_oob_std;
ecc->read_page_raw = nand_read_page_raw;
ecc->write_page_raw = nand_write_page_raw;
ecc->write_oob = nand_write_oob_std;
ecc->size = mtd->writesize;
ecc->bytes = 0;
ecc->strength = 0;
break;
default:
WARN(1, "Invalid NAND_ECC_MODE %d\n", ecc->mode);
ret = -EINVAL;
goto err_free;
}
/* For many systems, the standard OOB write also works for raw */
if (!ecc->read_oob_raw)
ecc->read_oob_raw = ecc->read_oob;
if (!ecc->write_oob_raw)
ecc->write_oob_raw = ecc->write_oob;
/* propagate ecc info to mtd_info */
mtd->ecc_strength = ecc->strength;
mtd->ecc_step_size = ecc->size;
/*
* Set the number of read / write steps for one page depending on ECC
* mode.
*/
ecc->steps = mtd->writesize / ecc->size;
if (ecc->steps * ecc->size != mtd->writesize) {
WARN(1, "Invalid ECC parameters\n");
ret = -EINVAL;
goto err_free;
}
ecc->total = ecc->steps * ecc->bytes;
/*
* The number of bytes available for a client to place data into
* the out of band area.
*/
ret = mtd_ooblayout_count_freebytes(mtd);
if (ret < 0)
ret = 0;
mtd->oobavail = ret;
/* ECC sanity check: warn if it's too weak */
if (!nand_ecc_strength_good(mtd))
pr_warn("WARNING: %s: the ECC used on your system is too weak compared to the one required by the NAND chip\n",
mtd->name);
/* Allow subpage writes up to ecc.steps. Not possible for MLC flash */
if (!(chip->options & NAND_NO_SUBPAGE_WRITE) && nand_is_slc(chip)) {
switch (ecc->steps) {
case 2:
mtd->subpage_sft = 1;
break;
case 4:
case 8:
case 16:
mtd->subpage_sft = 2;
break;
}
}
chip->subpagesize = mtd->writesize >> mtd->subpage_sft;
/* Initialize state */
chip->state = FL_READY;
/* Invalidate the pagebuffer reference */
chip->pagebuf = -1;
/* Large page NAND with SOFT_ECC should support subpage reads */
switch (ecc->mode) {
case NAND_ECC_SOFT:
if (chip->page_shift > 9)
chip->options |= NAND_SUBPAGE_READ;
break;
default:
break;
}
/* Fill in remaining MTD driver data */
mtd->type = nand_is_slc(chip) ? MTD_NANDFLASH : MTD_MLCNANDFLASH;
mtd->flags = (chip->options & NAND_ROM) ? MTD_CAP_ROM :
MTD_CAP_NANDFLASH;
mtd->_erase = nand_erase;
mtd->_point = NULL;
mtd->_unpoint = NULL;
mtd->_read = nand_read;
mtd->_write = nand_write;
mtd->_panic_write = panic_nand_write;
mtd->_read_oob = nand_read_oob;
mtd->_write_oob = nand_write_oob;
mtd->_sync = nand_sync;
mtd->_lock = NULL;
mtd->_unlock = NULL;
mtd->_suspend = nand_suspend;
mtd->_resume = nand_resume;
mtd->_reboot = nand_shutdown;
mtd->_block_isreserved = nand_block_isreserved;
mtd->_block_isbad = nand_block_isbad;
mtd->_block_markbad = nand_block_markbad;
mtd->writebufsize = mtd->writesize;
/*
* Initialize bitflip_threshold to its default prior scan_bbt() call.
* scan_bbt() might invoke mtd_read(), thus bitflip_threshold must be
* properly set.
*/
if (!mtd->bitflip_threshold)
mtd->bitflip_threshold = DIV_ROUND_UP(mtd->ecc_strength * 3, 4);
/* Check, if we should skip the bad block table scan */
if (chip->options & NAND_SKIP_BBTSCAN)
return 0;
/* Build bad block table */
return chip->scan_bbt(mtd);
err_free:
if (!(chip->options & NAND_OWN_BUFFERS))
kfree(chip->buffers);
return ret;
}
EXPORT_SYMBOL(nand_scan_tail);
/*
* is_module_text_address() isn't exported, and it's mostly a pointless
* test if this is a module _anyway_ -- they'd have to try _really_ hard
* to call us from in-kernel code if the core NAND support is modular.
*/
#ifdef MODULE
#define caller_is_module() (1)
#else
#define caller_is_module() \
is_module_text_address((unsigned long)__builtin_return_address(0))
#endif
/**
* nand_scan - [NAND Interface] Scan for the NAND device
* @mtd: MTD device structure
* @maxchips: number of chips to scan for
*
* This fills out all the uninitialized function pointers with the defaults.
* The flash ID is read and the mtd/chip structures are filled with the
* appropriate values.
*/
int nand_scan(struct mtd_info *mtd, int maxchips)
{
int ret;
ret = nand_scan_ident(mtd, maxchips, NULL);
if (!ret)
ret = nand_scan_tail(mtd);
return ret;
}
EXPORT_SYMBOL(nand_scan);
/**
* nand_release - [NAND Interface] Free resources held by the NAND device
* @mtd: MTD device structure
*/
void nand_release(struct mtd_info *mtd)
{
struct nand_chip *chip = mtd_to_nand(mtd);
if (chip->ecc.mode == NAND_ECC_SOFT &&
chip->ecc.algo == NAND_ECC_BCH)
nand_bch_free((struct nand_bch_control *)chip->ecc.priv);
mtd_device_unregister(mtd);
nand_release_data_interface(chip);
/* Free bad block table memory */
kfree(chip->bbt);
if (!(chip->options & NAND_OWN_BUFFERS))
kfree(chip->buffers);
/* Free bad block descriptor memory */
if (chip->badblock_pattern && chip->badblock_pattern->options
& NAND_BBT_DYNAMICSTRUCT)
kfree(chip->badblock_pattern);
}
EXPORT_SYMBOL_GPL(nand_release);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Steven J. Hill <sjhill@realitydiluted.com>");
MODULE_AUTHOR("Thomas Gleixner <tglx@linutronix.de>");
MODULE_DESCRIPTION("Generic NAND flash driver code");