Commit 5039fc9f authored by Sascha Hauer's avatar Sascha Hauer Committed by Boris Brezillon
Browse files

mtd: nand: mxc: Fix failed/corrected values for v1 controllers 



The v1 controller code has several flaws:
- We do not forward the number of corrected bitflips to the upper layers
- For 2k page NAND chips only the status results from the fourth subpage
  read are evaluated, so ECC failures in the other subpages remain
  uncovered
- When there are uncorrectable errors we have to increase the statistics
  counter, but still have to return successfully. Currently we return
  an error

This patch fixes this by introducing a v1 specific read_page function.

Signed-off-by: default avatarSascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: default avatarBoris Brezillon <boris.brezillon@bootlin.com>
parent 67b87f66

drivers/mtd/nand/mxc_nand.c

+60 −17
Original line number Diff line number Diff line
@@ -738,22 +738,65 @@ static void mxc_nand_enable_hwecc(struct mtd_info *mtd, int mode) 
static int mxc_nand_correct_data_v1(struct mtd_info *mtd, u_char *dat,

				 u_char *read_ecc, u_char *calc_ecc)

{

	struct nand_chip *nand_chip = mtd_to_nand(mtd);

	struct mxc_nand_host *host = nand_get_controller_data(nand_chip);

	return 0;

}



	/*

	 * 1-Bit errors are automatically corrected in HW.  No need for

	 * additional correction.  2-Bit errors cannot be corrected by

	 * HW ECC, so we need to return failure

	 */

	uint16_t ecc_status = get_ecc_status_v1(host);

static int mxc_nand_read_page_v1(struct nand_chip *chip, void *buf, void *oob,

				 bool ecc, int page)

{

	struct mtd_info *mtd = nand_to_mtd(chip);

	struct mxc_nand_host *host = nand_get_controller_data(chip);

	unsigned int bitflips_corrected = 0;

	int no_subpages;

	int i;



	host->devtype_data->enable_hwecc(chip, ecc);



	host->devtype_data->send_cmd(host, NAND_CMD_READ0, false);

	mxc_do_addr_cycle(mtd, 0, page);



	if (mtd->writesize > 512)

		host->devtype_data->send_cmd(host, NAND_CMD_READSTART, true);



	no_subpages = mtd->writesize >> 9;



	for (i = 0; i < no_subpages; i++) {

		uint16_t ecc_stats;



		/* NANDFC buffer 0 is used for page read/write */

		writew((host->active_cs << 4) | i, NFC_V1_V2_BUF_ADDR);



		writew(NFC_OUTPUT, NFC_V1_V2_CONFIG2);



		/* Wait for operation to complete */

		wait_op_done(host, true);



	if (((ecc_status & 0x3) == 2) || ((ecc_status >> 2) == 2)) {

		dev_dbg(host->dev, "HWECC uncorrectable 2-bit ECC error\n");

		return -EBADMSG;

		ecc_stats = get_ecc_status_v1(host);



		ecc_stats >>= 2;



		if (buf && ecc) {

			switch (ecc_stats & 0x3) {

			case 0:

			default:

				break;

			case 1:

				mtd->ecc_stats.corrected++;

				bitflips_corrected = 1;

				break;

			case 2:

				mtd->ecc_stats.failed++;

				break;

			}

		}

	}



	return 0;

	if (buf)

		memcpy32_fromio(buf, host->main_area0, mtd->writesize);

	if (oob)

		copy_spare(mtd, true, oob);



	return bitflips_corrected;

}



static int mxc_nand_correct_data_v2_v3(struct mtd_info *mtd, u_char *dat,
@@ -1494,6 +1537,7 @@ static struct nand_bbt_descr bbt_mirror_descr = { 
/* v1 + irqpending_quirk: i.MX21 */

static const struct mxc_nand_devtype_data imx21_nand_devtype_data = {

	.preset = preset_v1,

	.read_page = mxc_nand_read_page_v1,

	.send_cmd = send_cmd_v1_v2,

	.send_addr = send_addr_v1_v2,

	.send_page = send_page_v1,
@@ -1518,6 +1562,7 @@ static const struct mxc_nand_devtype_data imx21_nand_devtype_data = { 
/* v1 + !irqpending_quirk: i.MX27, i.MX31 */

static const struct mxc_nand_devtype_data imx27_nand_devtype_data = {

	.preset = preset_v1,

	.read_page = mxc_nand_read_page_v1,

	.send_cmd = send_cmd_v1_v2,

	.send_addr = send_addr_v1_v2,

	.send_page = send_page_v1,
@@ -1856,11 +1901,9 @@ static int mxcnd_probe(struct platform_device *pdev) 


	switch (this->ecc.mode) {

	case NAND_ECC_HW:

		if (host->devtype_data->read_page) {

		this->ecc.read_page = mxc_nand_read_page;

		this->ecc.read_page_raw = mxc_nand_read_page_raw;

		this->ecc.read_oob = mxc_nand_read_oob;

		}

		this->ecc.calculate = mxc_nand_calculate_ecc;

		this->ecc.hwctl = mxc_nand_enable_hwecc;

		this->ecc.correct = host->devtype_data->correct_data;

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