target/linux/mediatek/patches-5.15/120-10-v5.18-mtd-nand-fix-ecc-parameters-for-mt7622.patch

   1 From 41825166744c6e5664281611f5e6d9a2e9333c2b Mon Sep 17 00:00:00 2001
   2 From: Chuanhong Guo <gch981213@gmail.com>
   3 Date: Sat, 2 Apr 2022 22:31:20 +0800
   4 Subject: [PATCH 10/15] mtd: nand: fix ecc parameters for mt7622
   5
   6 According to the datasheet, mt7622 only has 5 ECC capabilities instead
   7 of 7, and the decoding error register is arranged  as follows:
   8 +------+---------+---------+---------+---------+
   9 | Bits |  19:15  |  14:10  |   9:5   |   4:0   |
  10 +------+---------+---------+---------+---------+
  11 | Name | ERRNUM3 | ERRNUM2 | ERRNUM1 | ERRNUM0 |
  12 +------+---------+---------+---------+---------+
  13 This means err_mask should be 0x1f instead of 0x3f and the number of
  14 bits shifted in mtk_ecc_get_stats should be 5 instead of 8.
  15
  16 This commit introduces err_shift for the difference in this register
  17 and fix other existing parameters.
  18
  19 Public MT7622 reference manual can be found on [0] and the info this
  20 commit is based on is from page 656 and page 660.
  21
  22 [0]: https://wiki.banana-pi.org/Banana_Pi_BPI-R64#Documents
  23
  24 Fixes: 98dea8d71931 ("mtd: nand: mtk: Support MT7622 NAND flash controller.")
  25 Signed-off-by: Chuanhong Guo <gch981213@gmail.com>
  26 (cherry picked from commit 088b769abd1bd21753002b17b696ae1778b16e8c)
  27 ---
  28  drivers/mtd/nand/raw/mtk_ecc.c | 12 ++++++++----
  29  1 file changed, 8 insertions(+), 4 deletions(-)
  30
  31 diff --git a/drivers/mtd/nand/raw/mtk_ecc.c b/drivers/mtd/nand/raw/mtk_ecc.c
  32 index c437d97debb8..ec9d1fb07006 100644
  33 --- a/drivers/mtd/nand/raw/mtk_ecc.c
  34 +++ b/drivers/mtd/nand/raw/mtk_ecc.c
  35 @@ -43,6 +43,7 @@
  36
  37  struct mtk_ecc_caps {
  38         u32 err_mask;
  39 +       u32 err_shift;
  40         const u8 *ecc_strength;
  41         const u32 *ecc_regs;
  42         u8 num_ecc_strength;
  43 @@ -76,7 +77,7 @@ static const u8 ecc_strength_mt2712[] = {
  44  };
  45
  46  static const u8 ecc_strength_mt7622[] = {
  47 -       4, 6, 8, 10, 12, 14, 16
  48 +       4, 6, 8, 10, 12
  49  };
  50
  51  enum mtk_ecc_regs {
  52 @@ -221,7 +222,7 @@ void mtk_ecc_get_stats(struct mtk_ecc *ecc, struct mtk_ecc_stats *stats,
  53         for (i = 0; i < sectors; i++) {
  54                 offset = (i >> 2) << 2;
  55                 err = readl(ecc->regs + ECC_DECENUM0 + offset);
  56 -               err = err >> ((i % 4) * 8);
  57 +               err = err >> ((i % 4) * ecc->caps->err_shift);
  58                 err &= ecc->caps->err_mask;
  59                 if (err == ecc->caps->err_mask) {
  60                         /* uncorrectable errors */
  61 @@ -449,6 +450,7 @@ EXPORT_SYMBOL(mtk_ecc_get_parity_bits);
  62
  63  static const struct mtk_ecc_caps mtk_ecc_caps_mt2701 = {
  64         .err_mask = 0x3f,
  65 +       .err_shift = 8,
  66         .ecc_strength = ecc_strength_mt2701,
  67         .ecc_regs = mt2701_ecc_regs,
  68         .num_ecc_strength = 20,
  69 @@ -459,6 +461,7 @@ static const struct mtk_ecc_caps mtk_ecc_caps_mt2701 = {
  70
  71  static const struct mtk_ecc_caps mtk_ecc_caps_mt2712 = {
  72         .err_mask = 0x7f,
  73 +       .err_shift = 8,
  74         .ecc_strength = ecc_strength_mt2712,
  75         .ecc_regs = mt2712_ecc_regs,
  76         .num_ecc_strength = 23,
  77 @@ -468,10 +471,11 @@ static const struct mtk_ecc_caps mtk_ecc_caps_mt2712 = {
  78  };
  79
  80  static const struct mtk_ecc_caps mtk_ecc_caps_mt7622 = {
  81 -       .err_mask = 0x3f,
  82 +       .err_mask = 0x1f,
  83 +       .err_shift = 5,
  84         .ecc_strength = ecc_strength_mt7622,
  85         .ecc_regs = mt7622_ecc_regs,
  86 -       .num_ecc_strength = 7,
  87 +       .num_ecc_strength = 5,
  88         .ecc_mode_shift = 4,
  89         .parity_bits = 13,
  90         .pg_irq_sel = 0,
  91 --
  92 2.35.1
  93