onenand_base.c

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	if (this->bufferram[i].block == block &&
	    this->bufferram[i].page == page &&
	    this->bufferram[i].valid)
		return 1;

	return 0;
}

/**
 * onenand_update_bufferram - [GENERIC] Update BufferRAM information
 * @param mtd		MTD data structure
 * @param addr		address to update
 * @param valid		valid flag
 *
 * Update BufferRAM information
 */
static int onenand_update_bufferram(struct mtd_info *mtd, loff_t addr,
		int valid)
{
	struct onenand_chip *this = mtd->priv;
	int block, page;
	int i;

	block = (int) (addr >> this->erase_shift);
	page = (int) (addr >> this->page_shift);
	page &= this->page_mask;

	/* Invalidate BufferRAM */
	for (i = 0; i < MAX_BUFFERRAM; i++) {
		if (this->bufferram[i].block == block &&
		    this->bufferram[i].page == page)
			this->bufferram[i].valid = 0;
	}

	/* Update BufferRAM */
	i = ONENAND_CURRENT_BUFFERRAM(this);
	this->bufferram[i].block = block;
	this->bufferram[i].page = page;
	this->bufferram[i].valid = valid;

	return 0;
}

/**
 * onenand_get_device - [GENERIC] Get chip for selected access
 * @param mtd		MTD device structure
 * @param new_state	the state which is requested
 *
 * Get the device and lock it for exclusive access
 */
static int onenand_get_device(struct mtd_info *mtd, int new_state)
{
	struct onenand_chip *this = mtd->priv;
	DECLARE_WAITQUEUE(wait, current);

	/*
	 * Grab the lock and see if the device is available
	 */
	while (1) {
		spin_lock(&this->chip_lock);
		if (this->state == FL_READY) {
			this->state = new_state;
			spin_unlock(&this->chip_lock);
			break;
		}
		if (new_state == FL_PM_SUSPENDED) {
			spin_unlock(&this->chip_lock);
			return (this->state == FL_PM_SUSPENDED) ? 0 : -EAGAIN;
		}
		set_current_state(TASK_UNINTERRUPTIBLE);
		add_wait_queue(&this->wq, &wait);
		spin_unlock(&this->chip_lock);
		schedule();
		remove_wait_queue(&this->wq, &wait);
	}

	return 0;
}

/**
 * onenand_release_device - [GENERIC] release chip
 * @param mtd		MTD device structure
 *
 * Deselect, release chip lock and wake up anyone waiting on the device
 */
static void onenand_release_device(struct mtd_info *mtd)
{
	struct onenand_chip *this = mtd->priv;

	/* Release the chip */
	spin_lock(&this->chip_lock);
	this->state = FL_READY;
	wake_up(&this->wq);
	spin_unlock(&this->chip_lock);
}

/**
 * onenand_read_ecc - [MTD Interface] Read data with ECC
 * @param mtd		MTD device structure
 * @param from		offset to read from
 * @param len		number of bytes to read
 * @param retlen	pointer to variable to store the number of read bytes
 * @param buf		the databuffer to put data
 * @param oob_buf	filesystem supplied oob data buffer
 * @param oobsel	oob selection structure
 *
 * OneNAND read with ECC
 */
static int onenand_read_ecc(struct mtd_info *mtd, loff_t from, size_t len,
	size_t *retlen, u_char *buf,
	u_char *oob_buf, struct nand_oobinfo *oobsel)
{
	struct onenand_chip *this = mtd->priv;
	int read = 0, column;
	int thislen;
	int ret = 0;

	DEBUG(MTD_DEBUG_LEVEL3, "onenand_read_ecc: from = 0x%08x, len = %i\n", (unsigned int) from, (int) len);

	/* Do not allow reads past end of device */
	if ((from + len) > mtd->size) {
		DEBUG(MTD_DEBUG_LEVEL0, "onenand_read_ecc: Attempt read beyond end of device\n");
		*retlen = 0;
		return -EINVAL;
	}

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

	/* TODO handling oob */

	while (read < len) {
		thislen = min_t(int, mtd->oobblock, len - read);

		column = from & (mtd->oobblock - 1);
		if (column + thislen > mtd->oobblock)
			thislen = mtd->oobblock - column;

		if (!onenand_check_bufferram(mtd, from)) {
			this->command(mtd, ONENAND_CMD_READ, from, mtd->oobblock);

			ret = this->wait(mtd, FL_READING);
			/* First copy data and check return value for ECC handling */
			onenand_update_bufferram(mtd, from, 1);
		}

		this->read_bufferram(mtd, ONENAND_DATARAM, buf, column, thislen);

		read += thislen;

		if (read == len)
			break;

		if (ret) {
			DEBUG(MTD_DEBUG_LEVEL0, "onenand_read_ecc: read failed = %d\n", ret);
			goto out;
		}

		from += thislen;
		buf += thislen;
	}

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

	/*
	 * Return success, if no ECC failures, else -EBADMSG
	 * fs driver will take care of that, because
	 * retlen == desired len and result == -EBADMSG
	 */
	*retlen = read;
	return ret;
}

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

/**
 * onenand_read_oob - [MTD Interface] OneNAND read out-of-band
 * @param mtd		MTD device structure
 * @param from		offset to read from
 * @param len		number of bytes to read
 * @param retlen	pointer to variable to store the number of read bytes
 * @param buf		the databuffer to put data
 *
 * OneNAND read out-of-band data from the spare area
 */
static int onenand_read_oob(struct mtd_info *mtd, loff_t from, size_t len,
	size_t *retlen, u_char *buf)
{
	struct onenand_chip *this = mtd->priv;
	int read = 0, thislen, column;
	int ret = 0;

	DEBUG(MTD_DEBUG_LEVEL3, "onenand_read_oob: from = 0x%08x, len = %i\n", (unsigned int) from, (int) len);

	/* Initialize return length value */
	*retlen = 0;

	/* Do not allow reads past end of device */
	if (unlikely((from + len) > mtd->size)) {
		DEBUG(MTD_DEBUG_LEVEL0, "onenand_read_oob: Attempt read beyond end of device\n");
		return -EINVAL;
	}

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

	column = from & (mtd->oobsize - 1);

	while (read < len) {
		thislen = mtd->oobsize - column;
		thislen = min_t(int, thislen, len);

		this->command(mtd, ONENAND_CMD_READOOB, from, mtd->oobsize);

		onenand_update_bufferram(mtd, from, 0);

		ret = this->wait(mtd, FL_READING);
		/* First copy data and check return value for ECC handling */

		this->read_bufferram(mtd, ONENAND_SPARERAM, buf, column, thislen);

		read += thislen;

		if (read == len)
			break;

		if (ret) {
			DEBUG(MTD_DEBUG_LEVEL0, "onenand_read_oob: read failed = %d\n", ret);
			goto out;
		}

		buf += thislen;

		/* Read more? */
		if (read < len) {
			/* Page size */
			from += mtd->oobblock;
			column = 0;
		}
	}

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

	*retlen = read;
	return ret;
}

#ifdef CONFIG_MTD_ONENAND_VERIFY_WRITE
/**
 * onenand_verify_oob - [GENERIC] verify the oob contents after a write
 * @param mtd		MTD device structure
 * @param buf		the databuffer to verify
 * @param to		offset to read from
 * @param len		number of bytes to read and compare
 *
 */
static int onenand_verify_oob(struct mtd_info *mtd, const u_char *buf, loff_t to, int len)
{
	struct onenand_chip *this = mtd->priv;
	char *readp = this->page_buf;
	int column = to & (mtd->oobsize - 1);
	int status, i;

	this->command(mtd, ONENAND_CMD_READOOB, to, mtd->oobsize);
	onenand_update_bufferram(mtd, to, 0);
	status = this->wait(mtd, FL_READING);
	if (status)
		return status;
		
	this->read_bufferram(mtd, ONENAND_SPARERAM, readp, column, len);
	
	for(i = 0; i < len; i++)
		if (buf[i] != 0xFF && buf[i] != readp[i])
			return -EBADMSG;

	return 0;
}

/**
 * onenand_verify_page - [GENERIC] verify the chip contents after a write
 * @param mtd		MTD device structure
 * @param buf		the databuffer to verify
 *
 * Check DataRAM area directly
 */
static int onenand_verify_page(struct mtd_info *mtd, u_char *buf, loff_t addr)
{
	struct onenand_chip *this = mtd->priv;
	void __iomem *dataram0, *dataram1;
	int ret = 0;

	this->command(mtd, ONENAND_CMD_READ, addr, mtd->oobblock);

	ret = this->wait(mtd, FL_READING);
	if (ret)
		return ret;

	onenand_update_bufferram(mtd, addr, 1);

	/* Check, if the two dataram areas are same */
	dataram0 = this->base + ONENAND_DATARAM;
	dataram1 = dataram0 + mtd->oobblock;

	if (memcmp(dataram0, dataram1, mtd->oobblock))
		return -EBADMSG;

	return 0;
}
#else
#define onenand_verify_page(...)	(0)
#define onenand_verify_oob(...)		(0)
#endif

#define NOTALIGNED(x)	((x & (mtd->oobblock - 1)) != 0)

/**
 * onenand_write_ecc - [MTD Interface] OneNAND write with ECC
 * @param mtd		MTD device structure
 * @param to		offset to write to
 * @param len		number of bytes to write
 * @param retlen	pointer to variable to store the number of written bytes
 * @param buf		the data to write
 * @param eccbuf	filesystem supplied oob data buffer
 * @param oobsel	oob selection structure
 *
 * OneNAND write with ECC
 */
static int onenand_write_ecc(struct mtd_info *mtd, loff_t to, size_t len,
	size_t *retlen, const u_char *buf,
	u_char *eccbuf, struct nand_oobinfo *oobsel)
{
	struct onenand_chip *this = mtd->priv;
	int written = 0;
	int ret = 0;

	DEBUG(MTD_DEBUG_LEVEL3, "onenand_write_ecc: to = 0x%08x, len = %i\n", (unsigned int) to, (int) len);

	/* Initialize retlen, in case of early exit */
	*retlen = 0;

	/* Do not allow writes past end of device */
	if (unlikely((to + len) > mtd->size)) {
		DEBUG(MTD_DEBUG_LEVEL0, "onenand_write_ecc: Attempt write to past end of device\n");
		return -EINVAL;
	}

	/* Reject writes, which are not page aligned */
        if (unlikely(NOTALIGNED(to)) || unlikely(NOTALIGNED(len))) {
                DEBUG(MTD_DEBUG_LEVEL0, "onenand_write_ecc: Attempt to write not page aligned data\n");
                return -EINVAL;
        }

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

	/* Loop until all data write */
	while (written < len) {
		int thislen = min_t(int, mtd->oobblock, len - written);

		this->command(mtd, ONENAND_CMD_BUFFERRAM, to, mtd->oobblock);

		this->write_bufferram(mtd, ONENAND_DATARAM, buf, 0, thislen);
		this->write_bufferram(mtd, ONENAND_SPARERAM, ffchars, 0, mtd->oobsize);

		this->command(mtd, ONENAND_CMD_PROG, to, mtd->oobblock);

		onenand_update_bufferram(mtd, to, 1);

		ret = this->wait(mtd, FL_WRITING);
		if (ret) {
			DEBUG(MTD_DEBUG_LEVEL0, "onenand_write_ecc: write filaed %d\n", ret);
			goto out;
		}

		written += thislen;

		/* Only check verify write turn on */
		ret = onenand_verify_page(mtd, (u_char *) buf, to);
		if (ret) {
			DEBUG(MTD_DEBUG_LEVEL0, "onenand_write_ecc: verify failed %d\n", ret);
			goto out;
		}

		if (written == len)
			break;

		to += thislen;
		buf += thislen;
	}

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

	*retlen = written;

	return ret;
}

/**
 * onenand_write - [MTD Interface] compability function for onenand_write_ecc
 * @param mtd		MTD device structure
 * @param to		offset to write to
 * @param len		number of bytes to write
 * @param retlen	pointer to variable to store the number of written bytes
 * @param buf		the data to write
 *
 * This function simply calls onenand_write_ecc
 * with oob buffer and oobsel = NULL
 */
static int onenand_write(struct mtd_info *mtd, loff_t to, size_t len,
	size_t *retlen, const u_char *buf)
{
	return onenand_write_ecc(mtd, to, len, retlen, buf, NULL, NULL);
}

/**
 * onenand_write_oob - [MTD Interface] OneNAND write out-of-band
 * @param mtd		MTD device structure
 * @param to		offset to write to
 * @param len		number of bytes to write
 * @param retlen	pointer to variable to store the number of written bytes
 * @param buf		the data to write
 *
 * OneNAND write out-of-band
 */
static int onenand_write_oob(struct mtd_info *mtd, loff_t to, size_t len,
	size_t *retlen, const u_char *buf)
{
	struct onenand_chip *this = mtd->priv;
	int column, ret = 0;
	int written = 0;

	DEBUG(MTD_DEBUG_LEVEL3, "onenand_write_oob: to = 0x%08x, len = %i\n", (unsigned int) to, (int) len);

	/* Initialize retlen, in case of early exit */
	*retlen = 0;

	/* Do not allow writes past end of device */
	if (unlikely((to + len) > mtd->size)) {
		DEBUG(MTD_DEBUG_LEVEL0, "onenand_write_oob: Attempt write to past end of device\n");
		return -EINVAL;
	}

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

	/* Loop until all data write */
	while (written < len) {
		int thislen = min_t(int, mtd->oobsize, len - written);

		column = to & (mtd->oobsize - 1);

		this->command(mtd, ONENAND_CMD_BUFFERRAM, to, mtd->oobsize);

		/* We send data to spare ram with oobsize
		 * to prevent byte access */
		memset(this->page_buf, 0xff, mtd->oobsize);
		memcpy(this->page_buf + column, buf, thislen);
		this->write_bufferram(mtd, ONENAND_SPARERAM, this->page_buf, 0, mtd->oobsize);

		this->command(mtd, ONENAND_CMD_PROGOOB, to, mtd->oobsize);

		onenand_update_bufferram(mtd, to, 0);

		ret = this->wait(mtd, FL_WRITING);
		if (ret) {
			DEBUG(MTD_DEBUG_LEVEL0, "onenand_write_oob: write filaed %d\n", ret);
			goto out;
		}

		ret = onenand_verify_oob(mtd, buf, to, thislen);
		if (ret) {
			DEBUG(MTD_DEBUG_LEVEL0, "onenand_write_oob: verify failed %d\n", ret);
			goto out;
		}

		written += thislen;

		if (written == len)
			break;

		to += thislen;
		buf += thislen;
	}