Coding Style cleanup: replace leading SPACEs by TABs

[people/ms/u-boot.git] / drivers / mtd / nand / nand_base.c

/*
 *  drivers/mtd/nand.c
 *
 *  Overview:
 *   This is the generic MTD driver for NAND flash devices. It should be
 *   capable of working with almost all NAND chips currently available.
 *   Basic support for AG-AND chips is provided.
 *
 *	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.
 *	The AG-AND chips have nice features for speed improvement,
 *	which are not supported yet. Read / program 4 pages in one go.
 *	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.
 *
 */

#include <common.h>

#define ENOTSUPP	524	/* Operation is not supported */

#include <malloc.h>
#include <watchdog.h>
#include <linux/err.h>
#include <linux/compat.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/nand.h>
#include <linux/mtd/nand_ecc.h>
#include <linux/mtd/nand_bch.h>

#ifdef CONFIG_MTD_PARTITIONS
#include <linux/mtd/partitions.h>
#endif

#include <asm/io.h>
#include <asm/errno.h>

/*
 * CONFIG_SYS_NAND_RESET_CNT is used as a timeout mechanism when resetting
 * a flash.  NAND flash is initialized prior to interrupts so standard timers
 * can't be used.  CONFIG_SYS_NAND_RESET_CNT should be set to a value
 * which is greater than (max NAND reset time / NAND status read time).
 * A conservative default of 200000 (500 us / 25 ns) is used as a default.
 */
#ifndef CONFIG_SYS_NAND_RESET_CNT
#define CONFIG_SYS_NAND_RESET_CNT 200000
#endif

/* Define default oob placement schemes for large and small page devices */
static struct nand_ecclayout nand_oob_8 = {
	.eccbytes = 3,
	.eccpos = {0, 1, 2},
	.oobfree = {
		{.offset = 3,
		 .length = 2},
		{.offset = 6,
		 .length = 2} }
};

static struct nand_ecclayout nand_oob_16 = {
	.eccbytes = 6,
	.eccpos = {0, 1, 2, 3, 6, 7},
	.oobfree = {
		{.offset = 8,
		 . length = 8} }
};

static struct nand_ecclayout nand_oob_64 = {
	.eccbytes = 24,
	.eccpos = {
		   40, 41, 42, 43, 44, 45, 46, 47,
		   48, 49, 50, 51, 52, 53, 54, 55,
		   56, 57, 58, 59, 60, 61, 62, 63},
	.oobfree = {
		{.offset = 2,
		 .length = 38} }
};

static struct nand_ecclayout nand_oob_128 = {
	.eccbytes = 48,
	.eccpos = {
		   80, 81, 82, 83, 84, 85, 86, 87,
		   88, 89, 90, 91, 92, 93, 94, 95,
		   96, 97, 98, 99, 100, 101, 102, 103,
		   104, 105, 106, 107, 108, 109, 110, 111,
		   112, 113, 114, 115, 116, 117, 118, 119,
		   120, 121, 122, 123, 124, 125, 126, 127},
	.oobfree = {
		{.offset = 2,
		 .length = 78} }
};

static int nand_get_device(struct nand_chip *chip, 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);

static int nand_wait(struct mtd_info *mtd, struct nand_chip *this);

static int check_offs_len(struct mtd_info *mtd,
					loff_t ofs, uint64_t len)
{
	struct nand_chip *chip = mtd->priv;
	int ret = 0;

	/* Start address must align on block boundary */
	if (ofs & ((1 << chip->phys_erase_shift) - 1)) {
		MTDDEBUG(MTD_DEBUG_LEVEL0, "%s: Unaligned address\n", __func__);
		ret = -EINVAL;
	}

	/* Length must align on block boundary */
	if (len & ((1 << chip->phys_erase_shift) - 1)) {
		MTDDEBUG(MTD_DEBUG_LEVEL0, "%s: Length not block aligned\n",
					__func__);
		ret = -EINVAL;
	}

	return ret;
}

/**
 * nand_release_device - [GENERIC] release chip
 * @mtd: MTD device structure
 *
 * Deselect, 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->priv;

	/* De-select the NAND device */
	chip->select_chip(mtd, -1);
}

/**
 * nand_read_byte - [DEFAULT] read one byte from the chip
 * @mtd: MTD device structure
 *
 * Default read function for 8bit buswidth.
 */
uint8_t nand_read_byte(struct mtd_info *mtd)
{
	struct nand_chip *chip = mtd->priv;
	return readb(chip->IO_ADDR_R);
}

/**
 * nand_read_byte16 - [DEFAULT] read one byte endianess aware from the chip
 * 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->priv;
	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->priv;
	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->priv;

	switch (chipnr) {
	case -1:
		chip->cmd_ctrl(mtd, NAND_CMD_NONE, 0 | NAND_CTRL_CHANGE);
		break;
	case 0:
		break;

	default:
		BUG();
	}
}

/**
 * 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.
 */
void nand_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
{
	int i;
	struct nand_chip *chip = mtd->priv;

	for (i = 0; i < len; i++)
		writeb(buf[i], chip->IO_ADDR_W);
}

/**
 * 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.
 */
void nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
{
	int i;
	struct nand_chip *chip = mtd->priv;

	for (i = 0; i < len; i++)
		buf[i] = readb(chip->IO_ADDR_R);
}

/**
 * nand_verify_buf - [DEFAULT] Verify chip data against buffer
 * @mtd: MTD device structure
 * @buf: buffer containing the data to compare
 * @len: number of bytes to compare
 *
 * Default verify function for 8bit buswidth.
 */
static int nand_verify_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
{
	int i;
	struct nand_chip *chip = mtd->priv;

	for (i = 0; i < len; i++)
		if (buf[i] != readb(chip->IO_ADDR_R))
			return -EFAULT;
	return 0;
}

/**
 * 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.
 */
void nand_write_buf16(struct mtd_info *mtd, const uint8_t *buf, int len)
{
	int i;
	struct nand_chip *chip = mtd->priv;
	u16 *p = (u16 *) buf;
	len >>= 1;

	for (i = 0; i < len; i++)
		writew(p[i], chip->IO_ADDR_W);

}

/**
 * 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.
 */
void nand_read_buf16(struct mtd_info *mtd, uint8_t *buf, int len)
{
	int i;
	struct nand_chip *chip = mtd->priv;
	u16 *p = (u16 *) buf;
	len >>= 1;

	for (i = 0; i < len; i++)
		p[i] = readw(chip->IO_ADDR_R);
}

/**
 * nand_verify_buf16 - [DEFAULT] Verify chip data against buffer
 * @mtd: MTD device structure
 * @buf: buffer containing the data to compare
 * @len: number of bytes to compare
 *
 * Default verify function for 16bit buswidth.
 */
static int nand_verify_buf16(struct mtd_info *mtd, const uint8_t *buf, int len)
{
	int i;
	struct nand_chip *chip = mtd->priv;
	u16 *p = (u16 *) buf;
	len >>= 1;

	for (i = 0; i < len; i++)
		if (p[i] != readw(chip->IO_ADDR_R))
			return -EFAULT;

	return 0;
}

/**
 * nand_block_bad - [DEFAULT] Read bad block marker from the chip
 * @mtd: MTD device structure
 * @ofs: offset from device start
 * @getchip: 0, if the chip is already selected
 *
 * Check, if the block is bad.
 */
static int nand_block_bad(struct mtd_info *mtd, loff_t ofs, int getchip)
{
	int page, chipnr, res = 0, i = 0;
	struct nand_chip *chip = mtd->priv;
	u16 bad;

	if (chip->bbt_options & NAND_BBT_SCANLASTPAGE)
		ofs += mtd->erasesize - mtd->writesize;

	page = (int)(ofs >> chip->page_shift) & chip->pagemask;

	if (getchip) {
		chipnr = (int)(ofs >> chip->chip_shift);

		nand_get_device(chip, mtd, FL_READING);

		/* Select the NAND device */
		chip->select_chip(mtd, chipnr);
	}

	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));

	if (getchip)
		nand_release_device(mtd);

	return res;
}

/**
 * nand_default_block_markbad - [DEFAULT] mark a block bad
 * @mtd: MTD device structure
 * @ofs: offset from device start
 *
 * This is the default implementation, which can be overridden by a hardware
 * specific driver. We try operations in the following order, according to our
 * bbt_options (NAND_BBT_NO_OOB_BBM and NAND_BBT_USE_FLASH):
 *  (1) erase the affected block, to allow OOB marker to be written cleanly
 *  (2) update in-memory BBT
 *  (3) write bad block marker to OOB area of affected block
 *  (4) update flash-based BBT
 * Note that we retain the first error encountered in (3) or (4), finish the
 * procedures, and dump the error in the end.
*/
static int nand_default_block_markbad(struct mtd_info *mtd, loff_t ofs)
{
	struct nand_chip *chip = mtd->priv;
	uint8_t buf[2] = { 0, 0 };
	int block, res, ret = 0, i = 0;
	int write_oob = !(chip->bbt_options & NAND_BBT_NO_OOB_BBM);

	if (write_oob) {
		struct erase_info einfo;

		/* Attempt erase before marking OOB */
		memset(&einfo, 0, sizeof(einfo));
		einfo.mtd = mtd;
		einfo.addr = ofs;
		einfo.len = 1 << chip->phys_erase_shift;
		nand_erase_nand(mtd, &einfo, 0);
	}

	/* Get block number */
	block = (int)(ofs >> chip->bbt_erase_shift);
	/* Mark block bad in memory-based BBT */
	if (chip->bbt)
		chip->bbt[block >> 2] |= 0x01 << ((block & 0x03) << 1);

	/* Write bad block marker to OOB */
	if (write_oob) {
		struct mtd_oob_ops ops;
		loff_t wr_ofs = ofs;

		nand_get_device(chip, mtd, FL_WRITING);

		ops.datbuf = NULL;
		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)
			wr_ofs += mtd->erasesize - mtd->writesize;
		do {
			res = nand_do_write_oob(mtd, wr_ofs, &ops);
			if (!ret)
				ret = res;

			i++;
			wr_ofs += mtd->writesize;
		} while ((chip->bbt_options & NAND_BBT_SCAN2NDPAGE) && i < 2);

		nand_release_device(mtd);
	}

	/* Update flash-based bad block table */
	if (chip->bbt_options & NAND_BBT_USE_FLASH) {
		res = nand_update_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->priv;

	/* 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;
}