Commit a8c65d50 authored by Boris BREZILLON's avatar Boris BREZILLON Committed by Brian Norris
Browse files

mtd: nand: simplify nand_bch_init() usage 



nand_bch_init() requires several arguments which could directly be deduced
from the mtd device. Get rid of those useless parameters.

nand_bch_init() is also requiring the caller to provide a proper eccbytes
value, while this value could be deduced from the ecc.size and
ecc.strength value. Fallback to eccbytes calculation when it is set to 0.

Signed-off-by: default avatarBoris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: default avatarBrian Norris <computersforpeace@gmail.com>
parent f2de0fa6

drivers/mtd/nand/nand_base.c

+2 −4
Original line number Diff line number Diff line
@@ -4279,10 +4279,8 @@ int nand_scan_tail(struct mtd_info *mtd) 
		}



		/* See nand_bch_init() for details. */

		ecc->bytes = DIV_ROUND_UP(

				ecc->strength * fls(8 * ecc->size), 8);

		ecc->priv = nand_bch_init(mtd, ecc->size, ecc->bytes,

					       &ecc->layout);

		ecc->bytes = 0;

		ecc->priv = nand_bch_init(mtd);

		if (!ecc->priv) {

			pr_warn("BCH ECC initialization failed!\n");

			BUG();

drivers/mtd/nand/nand_bch.c

+17 −10
Original line number Diff line number Diff line
@@ -107,9 +107,6 @@ EXPORT_SYMBOL(nand_bch_correct_data); 
/**

 * nand_bch_init - [NAND Interface] Initialize NAND BCH error correction

 * @mtd:	MTD block structure

 * @eccsize:	ecc block size in bytes

 * @eccbytes:	ecc length in bytes

 * @ecclayout:	output default layout

 *

 * Returns:

 *  a pointer to a new NAND BCH control structure, or NULL upon failure
@@ -123,14 +120,21 @@ EXPORT_SYMBOL(nand_bch_correct_data); 
 * @eccsize = 512  (thus, m=13 is the smallest integer such that 2^m-1 > 512*8)

 * @eccbytes = 7   (7 bytes are required to store m*t = 13*4 = 52 bits)

 */

struct nand_bch_control *

nand_bch_init(struct mtd_info *mtd, unsigned int eccsize, unsigned int eccbytes,

	      struct nand_ecclayout **ecclayout)

struct nand_bch_control *nand_bch_init(struct mtd_info *mtd)

{

	struct nand_chip *nand = mtd_to_nand(mtd);

	unsigned int m, t, eccsteps, i;

	struct nand_ecclayout *layout;

	struct nand_ecclayout *layout = nand->ecc.layout;

	struct nand_bch_control *nbc = NULL;

	unsigned char *erased_page;

	unsigned int eccsize = nand->ecc.size;

	unsigned int eccbytes = nand->ecc.bytes;

	unsigned int eccstrength = nand->ecc.strength;



	if (!eccbytes && eccstrength) {

		eccbytes = DIV_ROUND_UP(eccstrength * fls(8 * eccsize), 8);

		nand->ecc.bytes = eccbytes;

	}



	if (!eccsize || !eccbytes) {

		printk(KERN_WARNING "ecc parameters not supplied\n");
@@ -158,7 +162,7 @@ nand_bch_init(struct mtd_info *mtd, unsigned int eccsize, unsigned int eccbytes, 
	eccsteps = mtd->writesize/eccsize;



	/* if no ecc placement scheme was provided, build one */

	if (!*ecclayout) {

	if (!layout) {



		/* handle large page devices only */

		if (mtd->oobsize < 64) {
@@ -184,7 +188,7 @@ nand_bch_init(struct mtd_info *mtd, unsigned int eccsize, unsigned int eccbytes, 
		layout->oobfree[0].offset = 2;

		layout->oobfree[0].length = mtd->oobsize-2-layout->eccbytes;



		*ecclayout = layout;

		nand->ecc.layout = layout;

	}



	/* sanity checks */
@@ -192,7 +196,7 @@ nand_bch_init(struct mtd_info *mtd, unsigned int eccsize, unsigned int eccbytes, 
		printk(KERN_WARNING "eccsize %u is too large\n", eccsize);

		goto fail;

	}

	if ((*ecclayout)->eccbytes != (eccsteps*eccbytes)) {

	if (layout->eccbytes != (eccsteps*eccbytes)) {

		printk(KERN_WARNING "invalid ecc layout\n");

		goto fail;

	}
@@ -216,6 +220,9 @@ nand_bch_init(struct mtd_info *mtd, unsigned int eccsize, unsigned int eccbytes, 
	for (i = 0; i < eccbytes; i++)

		nbc->eccmask[i] ^= 0xff;



	if (!eccstrength)

		nand->ecc.strength = (eccbytes * 8) / fls(8 * eccsize);



	return nbc;

fail:

	nand_bch_free(nbc);

drivers/mtd/nand/omap2.c

+12 −16
Original line number Diff line number Diff line
@@ -1807,13 +1807,19 @@ static int omap_nand_probe(struct platform_device *pdev) 
		goto return_error;

	}



	/*

	 * Bail out earlier to let NAND_ECC_SOFT code create its own

	 * ecclayout instead of using ours.

	 */

	if (info->ecc_opt == OMAP_ECC_HAM1_CODE_SW) {

		nand_chip->ecc.mode = NAND_ECC_SOFT;

		goto scan_tail;

	}



	/* populate MTD interface based on ECC scheme */

	ecclayout		= &info->oobinfo;

	nand_chip->ecc.layout	= ecclayout;

	switch (info->ecc_opt) {

	case OMAP_ECC_HAM1_CODE_SW:

		nand_chip->ecc.mode = NAND_ECC_SOFT;

		break;



	case OMAP_ECC_HAM1_CODE_HW:

		pr_info("nand: using OMAP_ECC_HAM1_CODE_HW\n");

		nand_chip->ecc.mode             = NAND_ECC_HW;
@@ -1861,10 +1867,7 @@ static int omap_nand_probe(struct platform_device *pdev) 
		ecclayout->oobfree->offset	= 1 +

				ecclayout->eccpos[ecclayout->eccbytes - 1] + 1;

		/* software bch library is used for locating errors */

		nand_chip->ecc.priv		= nand_bch_init(mtd,

							nand_chip->ecc.size,

							nand_chip->ecc.bytes,

							&ecclayout);

		nand_chip->ecc.priv		= nand_bch_init(mtd);

		if (!nand_chip->ecc.priv) {

			dev_err(&info->pdev->dev, "unable to use BCH library\n");

			err = -EINVAL;
@@ -1925,10 +1928,7 @@ static int omap_nand_probe(struct platform_device *pdev) 
		ecclayout->oobfree->offset	= 1 +

				ecclayout->eccpos[ecclayout->eccbytes - 1] + 1;

		/* software bch library is used for locating errors */

		nand_chip->ecc.priv		= nand_bch_init(mtd,

							nand_chip->ecc.size,

							nand_chip->ecc.bytes,

							&ecclayout);

		nand_chip->ecc.priv		= nand_bch_init(mtd);

		if (!nand_chip->ecc.priv) {

			dev_err(&info->pdev->dev, "unable to use BCH library\n");

			err = -EINVAL;
@@ -2002,9 +2002,6 @@ static int omap_nand_probe(struct platform_device *pdev) 
		goto return_error;

	}



	if (info->ecc_opt == OMAP_ECC_HAM1_CODE_SW)

		goto scan_tail;



	/* all OOB bytes from oobfree->offset till end off OOB are free */

	ecclayout->oobfree->length = mtd->oobsize - ecclayout->oobfree->offset;

	/* check if NAND device's OOB is enough to store ECC signatures */
@@ -2015,7 +2012,6 @@ static int omap_nand_probe(struct platform_device *pdev) 
		err = -EINVAL;

		goto return_error;

	}

	nand_chip->ecc.layout = ecclayout;



scan_tail:

	/* second phase scan */

include/linux/mtd/nand_bch.h

+2 −6
Original line number Diff line number Diff line
@@ -32,9 +32,7 @@ int nand_bch_correct_data(struct mtd_info *mtd, u_char *dat, u_char *read_ecc, 
/*

 * Initialize BCH encoder/decoder

 */

struct nand_bch_control *

nand_bch_init(struct mtd_info *mtd, unsigned int eccsize,

	      unsigned int eccbytes, struct nand_ecclayout **ecclayout);

struct nand_bch_control *nand_bch_init(struct mtd_info *mtd);

/*

 * Release BCH encoder/decoder resources

 */
@@ -58,9 +56,7 @@ nand_bch_correct_data(struct mtd_info *mtd, unsigned char *buf, 
	return -ENOTSUPP;

}



static inline struct nand_bch_control *

nand_bch_init(struct mtd_info *mtd, unsigned int eccsize,

	      unsigned int eccbytes, struct nand_ecclayout **ecclayout)

static inline struct nand_bch_control *nand_bch_init(struct mtd_info *mtd)

{

	return NULL;

}

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