onenand_base.c

飞思卡尔芯片imx27下的MTD模块的驱动源码

	*retlen = written;

	return ret;
}

/**
 * onenand_write_oob - [MTD Interface] NAND write data and/or out-of-band
 * @mtd:	MTD device structure
 * @from:	offset to read from
 * @ops:	oob operation description structure
 */
static int onenand_write_oob(struct mtd_info *mtd, loff_t to,
			     struct mtd_oob_ops *ops)
{
	BUG_ON(ops->mode != MTD_OOB_PLACE);

	return onenand_do_write_oob(mtd, to + ops->ooboffs, ops->len,
				    &ops->retlen, ops->oobbuf);
}

/**
 * onenand_block_checkbad - [GENERIC] Check if a block is marked bad
 * @param mtd		MTD device structure
 * @param ofs		offset from device start
 * @param getchip	0, if the chip is already selected
 * @param 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 onenand_block_checkbad(struct mtd_info *mtd, loff_t ofs, int getchip, int allowbbt)
{
	struct onenand_chip *this = mtd->priv;
	struct bbm_info *bbm = this->bbm;

	/* Return info from the table */
	return bbm->isbad_bbt(mtd, ofs, allowbbt);
}

/**
 * onenand_erase - [MTD Interface] erase block(s)
 * @param mtd		MTD device structure
 * @param instr		erase instruction
 *
 * Erase one ore more blocks
 */
static int onenand_erase(struct mtd_info *mtd, struct erase_info *instr)
{
	struct onenand_chip *this = mtd->priv;
	unsigned int block_size;
	loff_t addr;
	int len;
	int ret = 0;

	DEBUG(MTD_DEBUG_LEVEL3, "onenand_erase: start = 0x%08x, len = %i\n", (unsigned int) instr->addr, (unsigned int) instr->len);

	block_size = (1 << this->erase_shift);

	/* Start address must align on block boundary */
	if (unlikely(instr->addr & (block_size - 1))) {
		DEBUG(MTD_DEBUG_LEVEL0, "onenand_erase: Unaligned address\n");
		return -EINVAL;
	}

	/* Length must align on block boundary */
	if (unlikely(instr->len & (block_size - 1))) {
		DEBUG(MTD_DEBUG_LEVEL0, "onenand_erase: Length not block aligned\n");
		return -EINVAL;
	}

	/* Do not allow erase past end of device */
	if (unlikely((instr->len + instr->addr) > mtd->size)) {
		DEBUG(MTD_DEBUG_LEVEL0, "onenand_erase: Erase past end of device\n");
		return -EINVAL;
	}

	instr->fail_addr = 0xffffffff;

	/* Grab the lock and see if the device is available */
	onenand_get_device(mtd, FL_ERASING);

	/* Loop throught the pages */
	len = instr->len;
	addr = instr->addr;

	instr->state = MTD_ERASING;

	while (len) {

		/* Check if we have a bad block, we do not erase bad blocks */
		if (onenand_block_checkbad(mtd, addr, 0, 0)) {
			printk (KERN_WARNING "onenand_erase: attempt to erase a bad block at addr 0x%08x\n", (unsigned int) addr);
			instr->state = MTD_ERASE_FAILED;
			goto erase_exit;
		}

		this->command(mtd, ONENAND_CMD_ERASE, addr, block_size);

		ret = this->wait(mtd, FL_ERASING);
		/* Check, if it is write protected */
		if (ret) {
			if (ret == -EPERM)
				DEBUG(MTD_DEBUG_LEVEL0, "onenand_erase: Device is write protected!!!\n");
			else
				DEBUG(MTD_DEBUG_LEVEL0, "onenand_erase: Failed erase, block %d\n", (unsigned) (addr >> this->erase_shift));
			instr->state = MTD_ERASE_FAILED;
			instr->fail_addr = addr;
			goto erase_exit;
		}

		len -= block_size;
		addr += block_size;
	}

	instr->state = MTD_ERASE_DONE;

erase_exit:

	ret = instr->state == MTD_ERASE_DONE ? 0 : -EIO;
	/* Do call back function */
	if (!ret)
		mtd_erase_callback(instr);

	/* Deselect and wake up anyone waiting on the device */
	onenand_release_device(mtd);

	return ret;
}

/**
 * onenand_sync - [MTD Interface] sync
 * @param mtd		MTD device structure
 *
 * Sync is actually a wait for chip ready function
 */
static void onenand_sync(struct mtd_info *mtd)
{
	DEBUG(MTD_DEBUG_LEVEL3, "onenand_sync: called\n");

	/* Grab the lock and see if the device is available */
	onenand_get_device(mtd, FL_SYNCING);

	/* Release it and go back */
	onenand_release_device(mtd);
}


/**
 * onenand_block_isbad - [MTD Interface] Check whether the block at the given offset is bad
 * @param mtd		MTD device structure
 * @param ofs		offset relative to mtd start
 *
 * Check whether the block is bad
 */
static int onenand_block_isbad(struct mtd_info *mtd, loff_t ofs)
{
	/* Check for invalid offset */
	if (ofs > mtd->size)
		return -EINVAL;

	return onenand_block_checkbad(mtd, ofs, 1, 0);
}

/**
 * onenand_default_block_markbad - [DEFAULT] mark a block bad
 * @param mtd		MTD device structure
 * @param ofs		offset from device start
 *
 * This is the default implementation, which can be overridden by
 * a hardware specific driver.
 */
static int onenand_default_block_markbad(struct mtd_info *mtd, loff_t ofs)
{
	struct onenand_chip *this = mtd->priv;
	struct bbm_info *bbm = this->bbm;
	u_char buf[2] = {0, 0};
	size_t retlen;
	int block;

	/* Get block number */
	block = ((int) ofs) >> bbm->bbt_erase_shift;
        if (bbm->bbt)
                bbm->bbt[block >> 2] |= 0x01 << ((block & 0x03) << 1);

        /* We write two bytes, so we dont have to mess with 16 bit access */
        ofs += mtd->oobsize + (bbm->badblockpos & ~0x01);
        return onenand_do_write_oob(mtd, ofs , 2, &retlen, buf);
}

/**
 * onenand_block_markbad - [MTD Interface] Mark the block at the given offset as bad
 * @param mtd		MTD device structure
 * @param ofs		offset relative to mtd start
 *
 * Mark the block as bad
 */
static int onenand_block_markbad(struct mtd_info *mtd, loff_t ofs)
{
	struct onenand_chip *this = mtd->priv;
	int ret;

	ret = onenand_block_isbad(mtd, ofs);
	if (ret) {
		/* If it was bad already, return success and do nothing */
		if (ret > 0)
			return 0;
		return ret;
	}

	return this->block_markbad(mtd, ofs);
}

/**
 * onenand_unlock - [MTD Interface] Unlock block(s)
 * @param mtd		MTD device structure
 * @param ofs		offset relative to mtd start
 * @param len		number of bytes to unlock
 *
 * Unlock one or more blocks
 */
static int onenand_unlock(struct mtd_info *mtd, loff_t ofs, size_t len)
{
	struct onenand_chip *this = mtd->priv;
	int start, end, block, value, status;

	start = ofs >> this->erase_shift;
	end = len >> this->erase_shift;

	/* Continuous lock scheme */
	if (this->options & ONENAND_HAS_CONT_LOCK) {
		/* Set start block address */
		this->write_word(start, this->base + ONENAND_REG_START_BLOCK_ADDRESS);
		/* Set end block address */
		this->write_word(start + end - 1, this->base + ONENAND_REG_END_BLOCK_ADDRESS);
		/* Write unlock command */
		this->command(mtd, ONENAND_CMD_UNLOCK, 0, 0);

		/* There's no return value */
		this->wait(mtd, FL_UNLOCKING);

		/* Sanity check */
		while (this->read_word(this->base + ONENAND_REG_CTRL_STATUS)
		    & ONENAND_CTRL_ONGO)
			continue;

		/* Check lock status */
		status = this->read_word(this->base + ONENAND_REG_WP_STATUS);
		if (!(status & ONENAND_WP_US))
			printk(KERN_ERR "wp status = 0x%x\n", status);

		return 0;
	}

	/* Block lock scheme */
	for (block = start; block < start + end; block++) {
		/* Set block address */
		value = onenand_block_address(this, block);
		this->write_word(value, this->base + ONENAND_REG_START_ADDRESS1);
		/* Select DataRAM for DDP */
		value = onenand_bufferram_address(this, block);
		this->write_word(value, this->base + ONENAND_REG_START_ADDRESS2);
		/* Set start block address */
		this->write_word(block, this->base + ONENAND_REG_START_BLOCK_ADDRESS);
		/* Write unlock command */
		this->command(mtd, ONENAND_CMD_UNLOCK, 0, 0);

		/* There's no return value */
		this->wait(mtd, FL_UNLOCKING);

		/* Sanity check */
		while (this->read_word(this->base + ONENAND_REG_CTRL_STATUS)
		    & ONENAND_CTRL_ONGO)
			continue;

		/* Check lock status */
		status = this->read_word(this->base + ONENAND_REG_WP_STATUS);
		if (!(status & ONENAND_WP_US))
			printk(KERN_ERR "block = %d, wp status = 0x%x\n", block, status);
	}

	return 0;
}

/**
 * onenand_check_lock_status - [OneNAND Interface] Check lock status
 * @param this		onenand chip data structure
 *
 * Check lock status
 */
static void onenand_check_lock_status(struct onenand_chip *this)
{
	unsigned int value, block, status;
	unsigned int end;

	end = this->chipsize >> this->erase_shift;
	for (block = 0; block < end; block++) {
		/* Set block address */
		value = onenand_block_address(this, block);
		this->write_word(value, this->base + ONENAND_REG_START_ADDRESS1);
		/* Select DataRAM for DDP */
		value = onenand_bufferram_address(this, block);
		this->write_word(value, this->base + ONENAND_REG_START_ADDRESS2);
		/* Set start block address */
		this->write_word(block, this->base + ONENAND_REG_START_BLOCK_ADDRESS);

		/* Check lock status */
		status = this->read_word(this->base + ONENAND_REG_WP_STATUS);
		if (!(status & ONENAND_WP_US))
			printk(KERN_ERR "block = %d, wp status = 0x%x\n", block, status);
	}
}

/**
 * onenand_unlock_all - [OneNAND Interface] unlock all blocks
 * @param mtd		MTD device structure
 *
 * Unlock all blocks
 */
static int onenand_unlock_all(struct mtd_info *mtd)
{
	struct onenand_chip *this = mtd->priv;

	if (this->options & ONENAND_HAS_UNLOCK_ALL) {
		/* Write unlock command */
		this->command(mtd, ONENAND_CMD_UNLOCK_ALL, 0, 0);

		/* There's no return value */
		this->wait(mtd, FL_UNLOCKING);

		/* Sanity check */
		while (this->read_word(this->base + ONENAND_REG_CTRL_STATUS)
		    & ONENAND_CTRL_ONGO)
			continue;

		/* Workaround for all block unlock in DDP */
		if (this->device_id & ONENAND_DEVICE_IS_DDP) {
			loff_t ofs;
			size_t len;

			/* 1st block on another chip */
			ofs = this->chipsize >> 1;
			len = 1 << this->erase_shift;

			onenand_unlock(mtd, ofs, len);
		}

		onenand_check_lock_status(this);

		return 0;
	}

	mtd->unlock(mtd, 0x0, this->chipsize);

	return 0;
}

#ifdef CONFIG_MTD_ONENAND_OTP

/* Interal OTP operation */
typedef int (*otp_op_t)(struct mtd_info *mtd, loff_t form, size_t len,
		size_t *retlen, u_char *buf);

/**
 * do_otp_read - [DEFAULT] Read OTP block area
 * @param mtd		MTD device structure
 * @param from		The offset to read
 * @param len		number of bytes to read
 * @param retlen	pointer to variable to store the number of readbytes
 * @param buf		the databuffer to put/get data
 *
 * Read OTP block area.
 */
static int do_otp_read(struct mtd_info *mtd, loff_t from, size_t len,
		size_t *retlen, u_char *buf)
{
	struct onenand_chip *this = mtd->priv;
	int ret;

	/* Enter OTP access mode */
	this->command(mtd, ONENAND_CMD_OTP_ACCESS, 0, 0);
	this->wait(mtd, FL_OTPING);

	ret = mtd->read(mtd, from, len, retlen, buf);

	/* Exit OTP access mode */
	this->command(mtd, ONENAND_CMD_RESET, 0, 0);
	this->wait(mtd, FL_RESETING);

	return ret;
}

/**
 * do_otp_write - [DEFAULT] Write OTP block area
 * @param mtd		MTD device structure
 * @param from		The offset to write
 * @param len		number of bytes to write
 * @param retlen	pointer to variable to store the number of write bytes
 * @param buf		the databuffer to put/get data
 *
 * Write OTP block area.
 */
static int do_otp_write(struct mtd_info *mtd, loff_t from, size_t len,
		size_t *retlen, u_char *buf)
{
	struct onenand_chip *this = mtd->priv;
	unsigned char *pbuf = buf;
	int ret;

	/* Force buffer page aligned */
	if (len < mtd->writesize) {
		memcpy(this->page_buf, buf, len);
		memset(this->page_buf + len, 0xff, mtd->writesize - len);
		pbuf = this->page_buf;
		len = mtd->writesize;
	}

	/* Enter OTP access mode */
	this->command(mtd, ONENAND_CMD_OTP_ACCESS, 0, 0);
	this->wait(mtd, FL_OTPING);

	ret = mtd->write(mtd, from, len, retlen, pbuf);

	/* Exit OTP access mode */
	this->command(mtd, ONENAND_CMD_RESET, 0, 0);
	this->wait(mtd, FL_RESETING);

	return ret;
}

/**
 * do_otp_lock - [DEFAULT] Lock OTP block area
 * @param mtd		MTD device structure
 * @param from		The offset to lock
 * @param len		number of bytes to lock
 * @param retlen	pointer to variable to store the number of lock bytes
 * @param buf		the databuffer to put/get data
 *
 * Lock OTP block area.
 */
static int do_otp_lock(struct mtd_info *mtd, loff_t from, size_t len,
		size_t *retlen, u_char *buf)
{
	struct onenand_chip *this = mtd->priv;
	int ret;

	/* Enter OTP access mode */
	this->command(mtd, ONENAND_CMD_OTP_ACCESS, 0, 0);
	this->wait(mtd, FL_OTPING);

	ret = onenand_do_write_oob(mtd, from, len, retlen, buf);

	/* Exit OTP access mode */
	this->command(mtd, ONENAND_CMD_RESET, 0, 0);
	this->wait(mtd, FL_RESETING);

	return ret;
}

/**
 * onenand_otp_walk - [DEFAULT] Handle OTP operation
 * @param mtd		MTD device structure
 * @param from		The offset to read/write
 * @param len		number of bytes to read/write
 * @param retlen	pointer to variable to store the number of read bytes
 * @param buf		the databuffer to put/get data
 * @param action	do given action
 * @param mode		specify user and factory
 *
 * Handle OTP operation.
 */
static int onenand_otp_walk(struct mtd_info *mtd, loff_t from, size_t len,
			size_t *retlen, u_char *buf,
			otp_op_t action, int mode)
{
	struct onenand_chip *this = mtd->priv;
	int otp_pages;
	int density;
	int ret = 0;

	*retlen = 0;

	density = this->device_id >> ONENAND_DEVICE_DENSITY_SHIFT;
	if (density < ONENAND_DEVICE_DENSITY_512Mb)
		otp_pages = 20;
	else
		otp_pages = 10;

	if (mode == MTD_OTP_FACTORY) {
		from += mtd->writesize * otp_pages;
		otp_pages = 64 - otp_pages;
	}