Re: [U-Boot] [PATCH v3 2/3] mtd: nand: omap: fix ecclayout->oobfree->offset

removing stable@vger.kernel.org from CC list. (git send-email --suppress-cc=cc din't work for me)

From: Gupta, Pekon

1. In current implementation, ecclayout->oobfree->offset is calculated with

respect to ecclayout->eccpos[0] which is incorrect because ECC bytes may not be stored contiguously in OOB. So, this patch calculates ecclayout->oobfree->offset with respect to last ECC byte-position 'eccpos[ecclayout->eccbytes-1]'.

2. ECC layout of some ecc-schemes expects reserved-markers at specific eccpos[]

which should not be over-written by any file-system metadata. So this patch aligns oobfree->offset taking into account of such markers.

CC: stable@vger.kernel.org # 3.13.x+ Tested-by: Enric Balletbo i Serra eballetbo@gmail.com Tested-by: Stefan Roese sr@denx.de Signed-off-by: Pekon Gupta pekon@ti.com

---

drivers/mtd/nand/omap2.c | 25 +++++++++++++++---------- 1 file changed, 15 insertions(+), 10 deletions(-)

diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c index 34ef941..58685ab 100644 --- a/drivers/mtd/nand/omap2.c +++ b/drivers/mtd/nand/omap2.c @@ -1832,8 +1832,9 @@ static int omap_nand_probe(struct platform_device *pdev) oob_index = 1; for (i = 0; i < ecclayout->eccbytes; i++, oob_index++) ecclayout->eccpos[i] = oob_index;

• ecclayout->oobfree->offset	= ecclayout->eccpos[0] +
  

• 					ecclayout->eccbytes;
  

• /* no reserved-marker in ecclayout for this ecc-scheme */
  

• ecclayout->oobfree->offset	=
  

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

  break;

  case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW:

@@ -1856,8 +1857,9 @@ static int omap_nand_probe(struct platform_device *pdev) if (((i + 1) % nand_chip->ecc.bytes) == 0) oob_index++; }

• ecclayout->oobfree->offset	= ecclayout->eccpos[0] +
  

• 					ecclayout->eccbytes;
  

• /* include reserved-marker in ecclayout->oobfree calculation */
  

• 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,

@@ -1894,8 +1896,9 @@ static int omap_nand_probe(struct platform_device *pdev) oob_index = BADBLOCK_MARKER_LENGTH; for (i = 0; i < ecclayout->eccbytes; i++, oob_index++) ecclayout->eccpos[i] = oob_index;

• ecclayout->oobfree->offset	= ecclayout->eccpos[0] +
  

• 					ecclayout->eccbytes;
  

• /* reserved marker already included in ecclayout->eccbytes */
  

• ecclayout->oobfree->offset	=
  

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

  /* This ECC scheme requires ELM H/W block */ if (is_elm_present(info, pdata->elm_of_node, BCH4_ECC) < 0) { pr_err("nand: error: could not initialize ELM\n");

@@ -1929,8 +1932,9 @@ static int omap_nand_probe(struct platform_device *pdev) if (((i + 1) % nand_chip->ecc.bytes) == 0) oob_index++; }

• ecclayout->oobfree->offset	= ecclayout->eccpos[0] +
  

• 					ecclayout->eccbytes;
  

• /* include reserved-marker in ecclayout->oobfree calculation */
  

• 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,

@@ -1974,8 +1978,9 @@ static int omap_nand_probe(struct platform_device *pdev) oob_index = BADBLOCK_MARKER_LENGTH; for (i = 0; i < ecclayout->eccbytes; i++, oob_index++) ecclayout->eccpos[i] = oob_index;

• ecclayout->oobfree->offset	= ecclayout->eccpos[0] +
  

• 					ecclayout->eccbytes;
  

• /* reserved marker already included in ecclayout->eccbytes */
  

• ecclayout->oobfree->offset	=
  

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

  break;

#else pr_err("nand: error: CONFIG_MTD_NAND_OMAP_BCH not enabled\n"); -- 1.8.5.1.163.gd7aced9

With regards, pekon