target/linux/generic/pending-5.10/481-mtd-spi-nor-rework-broken-flash-reset-support.patch

   1 From ea92cbb50a78404e29de2cc3999a240615ffb1c8 Mon Sep 17 00:00:00 2001
   2 From: Chuanhong Guo <gch981213@gmail.com>
   3 Date: Mon, 6 Apr 2020 17:58:48 +0800
   4 Subject: [PATCH] mtd: spi-nor: rework broken-flash-reset support
   5
   6 Instead of resetting flash to 3B address on remove hook, this
   7 implementation only enters 4B mode when needed, which prevents
   8 more unexpected reboot stuck. This implementation makes it only
   9 break when a kernel panic happens during flash operation on 16M+
  10 areas.
  11 *OpenWrt only*: silent broken-flash-reset warning. We are not dealing
  12 with vendors and it's unpleasant for users to se that unnecessary
  13 and long WARN_ON print.
  14
  15 Signed-off-by: Chuanhong Guo <gch981213@gmail.com>
  16 ---
  17  drivers/mtd/spi-nor/spi-nor.c | 52 +++++++++++++++++++++++++++++++++--
  18  1 file changed, 49 insertions(+), 3 deletions(-)
  19
  20 --- a/drivers/mtd/spi-nor/core.c
  21 +++ b/drivers/mtd/spi-nor/core.c
  22 @@ -1447,6 +1447,23 @@ destroy_erase_cmd_list:
  23         return ret;
  24  }
  25
  26 +int spi_nor_check_set_addr_width(struct spi_nor *nor, loff_t addr)
  27 +{
  28 +       u8 addr_width;
  29 +
  30 +       if ((nor->flags & (SNOR_F_4B_OPCODES | SNOR_F_BROKEN_RESET)) !=
  31 +           SNOR_F_BROKEN_RESET)
  32 +               return 0;
  33 +
  34 +       addr_width = addr & 0xff000000 ? 4 : 3;
  35 +       if (nor->addr_width == addr_width)
  36 +               return 0;
  37 +
  38 +       nor->addr_width = addr_width;
  39 +
  40 +       return nor->params->set_4byte_addr_mode(nor, addr_width == 4);
  41 +}
  42 +
  43  /*
  44   * Erase an address range on the nor chip.  The address range may extend
  45   * one or more erase sectors.  Return an error is there is a problem erasing.
  46 @@ -1474,6 +1491,10 @@ static int spi_nor_erase(struct mtd_info
  47         if (ret)
  48                 return ret;
  49
  50 +       ret = spi_nor_check_set_addr_width(nor, instr->addr + instr->len);
  51 +       if (ret < 0)
  52 +               return ret;
  53 +
  54         /* whole-chip erase? */
  55         if (len == mtd->size && !(nor->flags & SNOR_F_NO_OP_CHIP_ERASE)) {
  56                 unsigned long timeout;
  57 @@ -1533,6 +1554,7 @@ static int spi_nor_erase(struct mtd_info
  58         ret = spi_nor_write_disable(nor);
  59
  60  erase_err:
  61 +       spi_nor_check_set_addr_width(nor, 0);
  62         spi_nor_unlock_and_unprep(nor);
  63
  64         return ret;
  65 @@ -1872,7 +1894,9 @@ static int spi_nor_lock(struct mtd_info
  66         if (ret)
  67                 return ret;
  68
  69 +       spi_nor_check_set_addr_width(nor, ofs + len);
  70         ret = nor->params->locking_ops->lock(nor, ofs, len);
  71 +       spi_nor_check_set_addr_width(nor, 0);
  72
  73         spi_nor_unlock_and_unprep(nor);
  74         return ret;
  75 @@ -1887,7 +1911,9 @@ static int spi_nor_unlock(struct mtd_inf
  76         if (ret)
  77                 return ret;
  78
  79 +       spi_nor_check_set_addr_width(nor, ofs + len);
  80         ret = nor->params->locking_ops->unlock(nor, ofs, len);
  81 +       spi_nor_check_set_addr_width(nor, 0);
  82
  83         spi_nor_unlock_and_unprep(nor);
  84         return ret;
  85 @@ -1902,7 +1928,9 @@ static int spi_nor_is_locked(struct mtd_
  86         if (ret)
  87                 return ret;
  88
  89 +       spi_nor_check_set_addr_width(nor, ofs + len);
  90         ret = nor->params->locking_ops->is_locked(nor, ofs, len);
  91 +       spi_nor_check_set_addr_width(nor, 0);
  92
  93         spi_nor_unlock_and_unprep(nor);
  94         return ret;
  95 @@ -2095,6 +2123,10 @@ static int spi_nor_read(struct mtd_info
  96         if (ret)
  97                 return ret;
  98
  99 +       ret = spi_nor_check_set_addr_width(nor, from + len);
 100 +       if (ret < 0)
 101 +               return ret;
 102 +
 103         while (len) {
 104                 loff_t addr = from;
 105
 106 @@ -2118,6 +2150,7 @@ static int spi_nor_read(struct mtd_info
 107         ret = 0;
 108
 109  read_err:
 110 +       spi_nor_check_set_addr_width(nor, 0);
 111         spi_nor_unlock_and_unprep(nor);
 112         return ret;
 113  }
 114 @@ -2140,6 +2173,10 @@ static int spi_nor_write(struct mtd_info
 115         if (ret)
 116                 return ret;
 117
 118 +       ret = spi_nor_check_set_addr_width(nor, to + len);
 119 +       if (ret < 0)
 120 +               return ret;
 121 +
 122         for (i = 0; i < len; ) {
 123                 ssize_t written;
 124                 loff_t addr = to + i;
 125 @@ -2182,6 +2219,7 @@ static int spi_nor_write(struct mtd_info
 126         }
 127
 128  write_err:
 129 +       spi_nor_check_set_addr_width(nor, 0);
 130         spi_nor_unlock_and_unprep(nor);
 131         return ret;
 132  }
 133 @@ -2977,9 +3015,13 @@ static int spi_nor_init(struct spi_nor *
 134                  * reboots (e.g., crashes). Warn the user (or hopefully, system
 135                  * designer) that this is bad.
 136                  */
 137 -               WARN_ONCE(nor->flags & SNOR_F_BROKEN_RESET,
 138 -                         "enabling reset hack; may not recover from unexpected reboots\n");
 139 -               nor->params->set_4byte_addr_mode(nor, true);
 140 +               if (nor->flags & SNOR_F_BROKEN_RESET) {
 141 +                       dev_warn(nor->dev,
 142 +                               "enabling reset hack; may not recover from unexpected reboots\n");
 143 +                       nor->addr_width = 3;
 144 +               } else {
 145 +                       nor->params->set_4byte_addr_mode(nor, true);
 146 +               }
 147         }
 148
 149         return 0;
 150 --- a/drivers/mtd/spi-nor/core.h
 151 +++ b/drivers/mtd/spi-nor/core.h
 152 @@ -400,6 +400,7 @@ extern const struct spi_nor_manufacturer
 153  extern const struct spi_nor_manufacturer spi_nor_xmc;
 154  extern const struct spi_nor_manufacturer spi_nor_xtx;
 155
 156 +int spi_nor_check_set_addr_width(struct spi_nor *nor, loff_t addr);
 157  int spi_nor_write_enable(struct spi_nor *nor);
 158  int spi_nor_write_disable(struct spi_nor *nor);
 159  int spi_nor_set_4byte_addr_mode(struct spi_nor *nor, bool enable);
 160 --- a/drivers/mtd/spi-nor/sst.c
 161 +++ b/drivers/mtd/spi-nor/sst.c
 162 @@ -55,6 +55,10 @@ static int sst_write(struct mtd_info *mt
 163         if (ret)
 164                 return ret;
 165
 166 +       ret = spi_nor_check_set_addr_width(nor, to + len);
 167 +       if (ret < 0)
 168 +               return ret;
 169 +
 170         ret = spi_nor_write_enable(nor);
 171         if (ret)
 172                 goto out;
 173 @@ -124,6 +128,7 @@ static int sst_write(struct mtd_info *mt
 174         }
 175  out:
 176         *retlen += actual;
 177 +       spi_nor_check_set_addr_width(nor, 0);
 178         spi_nor_unlock_and_unprep(nor);
 179         return ret;
 180  }