target/linux/generic/patches-4.1/144-mtd-bcm47xxpart-don-t-fail-because-of-bit-flips.patch

   1 From dfe4b4c732365fc1d83c2d2fd9cc18054ae850b7 Mon Sep 17 00:00:00 2001
   2 From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <zajec5@gmail.com>
   3 Date: Sun, 6 Dec 2015 11:24:05 +0100
   4 Subject: [PATCH] mtd: bcm47xxpart: don't fail because of bit-flips
   5 MIME-Version: 1.0
   6 Content-Type: text/plain; charset=UTF-8
   7 Content-Transfer-Encoding: 8bit
   8
   9 Bit-flip errors may occur on NAND flashes and are harmless. Handle them
  10 gracefully as read content is still reliable and can be parsed.
  11
  12 Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
  13 ---
  14  drivers/mtd/bcm47xxpart.c | 38 ++++++++++++++++++++++----------------
  15  1 file changed, 22 insertions(+), 16 deletions(-)
  16
  17 diff --git a/drivers/mtd/bcm47xxpart.c b/drivers/mtd/bcm47xxpart.c
  18 index 4450e74..1ab3451 100644
  19 --- a/drivers/mtd/bcm47xxpart.c
  20 +++ b/drivers/mtd/bcm47xxpart.c
  21 @@ -66,11 +66,13 @@ static const char *bcm47xxpart_trx_data_part_name(struct mtd_info *master,
  22  {
  23         uint32_t buf;
  24         size_t bytes_read;
  25 +       int err;
  26
  27 -       if (mtd_read(master, offset, sizeof(buf), &bytes_read,
  28 -                    (uint8_t *)&buf) < 0) {
  29 -               pr_err("mtd_read error while parsing (offset: 0x%X)!\n",
  30 -                       offset);
  31 +       err  = mtd_read(master, offset, sizeof(buf), &bytes_read,
  32 +                       (uint8_t *)&buf);
  33 +       if (err && !mtd_is_bitflip(err)) {
  34 +               pr_err("mtd_read error while parsing (offset: 0x%X): %d\n",
  35 +                       offset, err);
  36                 goto out_default;
  37         }
  38
  39 @@ -95,6 +97,7 @@ static int bcm47xxpart_parse(struct mtd_info *master,
  40         int trx_part = -1;
  41         int last_trx_part = -1;
  42         int possible_nvram_sizes[] = { 0x8000, 0xF000, 0x10000, };
  43 +       int err;
  44
  45         /*
  46          * Some really old flashes (like AT45DB*) had smaller erasesize-s, but
  47 @@ -128,10 +131,11 @@ static int bcm47xxpart_parse(struct mtd_info *master,
  48                 }
  49
  50                 /* Read beginning of the block */
  51 -               if (mtd_read(master, offset, BCM47XXPART_BYTES_TO_READ,
  52 -                            &bytes_read, (uint8_t *)buf) < 0) {
  53 -                       pr_err("mtd_read error while parsing (offset: 0x%X)!\n",
  54 -                              offset);
  55 +               err = mtd_read(master, offset, BCM47XXPART_BYTES_TO_READ,
  56 +                              &bytes_read, (uint8_t *)buf);
  57 +               if (err && !mtd_is_bitflip(err)) {
  58 +                       pr_err("mtd_read error while parsing (offset: 0x%X): %d\n",
  59 +                              offset, err);
  60                         continue;
  61                 }
  62
  63 @@ -254,10 +258,11 @@ static int bcm47xxpart_parse(struct mtd_info *master,
  64                 }
  65
  66                 /* Read middle of the block */
  67 -               if (mtd_read(master, offset + 0x8000, 0x4,
  68 -                            &bytes_read, (uint8_t *)buf) < 0) {
  69 -                       pr_err("mtd_read error while parsing (offset: 0x%X)!\n",
  70 -                              offset);
  71 +               err = mtd_read(master, offset + 0x8000, 0x4, &bytes_read,
  72 +                              (uint8_t *)buf);
  73 +               if (err && !mtd_is_bitflip(err)) {
  74 +                       pr_err("mtd_read error while parsing (offset: 0x%X): %d\n",
  75 +                              offset, err);
  76                         continue;
  77                 }
  78
  79 @@ -277,10 +282,11 @@ static int bcm47xxpart_parse(struct mtd_info *master,
  80                 }
  81
  82                 offset = master->size - possible_nvram_sizes[i];
  83 -               if (mtd_read(master, offset, 0x4, &bytes_read,
  84 -                            (uint8_t *)buf) < 0) {
  85 -                       pr_err("mtd_read error while reading at offset 0x%X!\n",
  86 -                              offset);
  87 +               err = mtd_read(master, offset, 0x4, &bytes_read,
  88 +                              (uint8_t *)buf);
  89 +               if (err && !mtd_is_bitflip(err)) {
  90 +                       pr_err("mtd_read error while reading (offset 0x%X): %d\n",
  91 +                              offset, err);
  92                         continue;
  93                 }
  94
  95 --
  96 1.8.4.5
  97