target/linux/s3c24xx/patches-2.6.24/1066-fix-hwecc-2410.patch.patch

   1 From b6817bed9516a65276ee92437697cb46136df882 Mon Sep 17 00:00:00 2001
   2 From: mokopatches <mokopatches@openmoko.org>
   3 Date: Sun, 13 Apr 2008 07:23:57 +0100
   4 Subject: [PATCH] fix-hwecc-2410.patch
   5  S3C24xx ECC mis-calculates the bit to flip:
   6  http://lists.infradead.org/pipermail/linux-mtd/2007-October/019586.html
   7  If the error couldn't be corrected, we returned "no problem" :-(
   8  http://lists.infradead.org/pipermail/linux-mtd/2007-October/019615.html
   9
  10 Signed-off-by: Werner Almesberger <werner@openmoko.org>
  11 ---
  12  drivers/mtd/nand/s3c2410.c |   28 +++++++++++++---------------
  13  1 files changed, 13 insertions(+), 15 deletions(-)
  14
  15 diff --git a/drivers/mtd/nand/s3c2410.c b/drivers/mtd/nand/s3c2410.c
  16 index f83bed9..f7dd4e0 100644
  17 --- a/drivers/mtd/nand/s3c2410.c
  18 +++ b/drivers/mtd/nand/s3c2410.c
  19 @@ -364,23 +364,21 @@ static int s3c2410_nand_correct_data(struct mtd_info *mtd, u_char *dat,
  20             ((diff2 ^ (diff2 >> 1)) & 0x55) == 0x55) {
  21                 /* calculate the bit position of the error */
  22
  23 -               bit  = (diff2 >> 2) & 1;
  24 -               bit |= (diff2 >> 3) & 2;
  25 -               bit |= (diff2 >> 4) & 4;
  26 +               bit  = ((diff2 >> 3) & 1) |
  27 +                      ((diff2 >> 4) & 2) |
  28 +                      ((diff2 >> 5) & 4);
  29
  30                 /* calculate the byte position of the error */
  31
  32 -               byte  = (diff1 << 1) & 0x80;
  33 -               byte |= (diff1 << 2) & 0x40;
  34 -               byte |= (diff1 << 3) & 0x20;
  35 -               byte |= (diff1 << 4) & 0x10;
  36 -
  37 -               byte |= (diff0 >> 3) & 0x08;
  38 -               byte |= (diff0 >> 2) & 0x04;
  39 -               byte |= (diff0 >> 1) & 0x02;
  40 -               byte |= (diff0 >> 0) & 0x01;
  41 -
  42 -               byte |= (diff2 << 8) & 0x100;
  43 +               byte = ((diff2 << 7) & 0x100) |
  44 +                      ((diff1 << 0) & 0x80)  |
  45 +                      ((diff1 << 1) & 0x40)  |
  46 +                      ((diff1 << 2) & 0x20)  |
  47 +                      ((diff1 << 3) & 0x10)  |
  48 +                      ((diff0 >> 4) & 0x08)  |
  49 +                      ((diff0 >> 3) & 0x04)  |
  50 +                      ((diff0 >> 2) & 0x02)  |
  51 +                      ((diff0 >> 1) & 0x01);
  52
  53                 dev_dbg(info->device, "correcting error bit %d, byte %d\n",
  54                         bit, byte);
  55 @@ -399,7 +397,7 @@ static int s3c2410_nand_correct_data(struct mtd_info *mtd, u_char *dat,
  56         if ((diff0 & ~(1<<fls(diff0))) == 0)
  57                 return 1;
  58
  59 -       return 0;
  60 +       return -EBADMSG;
  61  }
  62
  63  /* ECC functions
  64 --
  65 1.5.6.5
  66