git.openwrt.org Git - openwrt/staging/blogic.git/blob

   1 From 986172ece10eee928ce66597d76f3f40ac3d25f7 Mon Sep 17 00:00:00 2001
   2 From: Yunhui Cui <yunhui.cui@nxp.com>
   3 Date: Mon, 8 Aug 2016 14:24:13 +0800
   4 Subject: [PATCH 86/93] driver: spi: add spansion s25fs-s family
   5  protect/unprotect
   6
   7 In order to support spansion s25fs512s flash protect/unprotect:
   8
   9 [1] Fill callbak flash->lock/unlock/is_locked by spansion_lock/
  10 unlock/is_locked.
  11
  12 [2] Achieve protect/unprotected by operating sr1nv, cr1nv.
  13
  14 Signed-off-by: Yunhui Cui <yunhui.cui@nxp.com>
  15 ---
  16  drivers/mtd/spi/spi_flash.c |  194 +++++++++++++++++++++++++++++++++++++++++++
  17  1 file changed, 194 insertions(+)
  18
  19 diff --git a/drivers/mtd/spi/spi_flash.c b/drivers/mtd/spi/spi_flash.c
  20 index e04bd55..87a92e9 100644
  21 --- a/drivers/mtd/spi/spi_flash.c
  22 +++ b/drivers/mtd/spi/spi_flash.c
  23 @@ -877,6 +877,193 @@ int stm_unlock(struct spi_flash *flash, u32 ofs, size_t len)
  24  }
  25  #endif
  26
  27 +#if defined(CONFIG_SPI_FLASH_SPANSION)
  28 +/*
  29 + * Return 1 if the entire region is locked, 0 otherwise
  30 + */
  31 +static int spansion_is_locked_sr(struct spi_flash *flash, u32 ofs, u32 len,
  32 +                           u8 sr)
  33 +{
  34 +       loff_t lock_offs;
  35 +       u32 lock_len;
  36 +
  37 +       stm_get_locked_range(flash, sr, &lock_offs, &lock_len);
  38 +
  39 +       return (ofs + len <= lock_offs + lock_len) && (ofs >= lock_offs);
  40 +}
  41 +
  42 +/*
  43 + * Check if a region of the flash is (completely) locked. See spansion_lock() for
  44 + * more info.
  45 + *
  46 + * Returns 1 if entire region is locked, 0 if any portion is unlocked, and
  47 + * negative on errors.
  48 + */
  49 +int spansion_is_locked(struct spi_flash *flash, u32 ofs, size_t len)
  50 +{
  51 +       u8 cmd[4];
  52 +       u32 sr1nv_offset = 0x0;
  53 +       u8 sr1nv;
  54 +       int ret;
  55 +
  56 +       cmd[0] = CMD_SPANSION_RDAR;
  57 +       cmd[1] = sr1nv_offset >> 16;
  58 +       cmd[2] = sr1nv_offset >> 8;
  59 +       cmd[3] = sr1nv_offset >> 0;
  60 +
  61 +       ret = spi_flash_cmd_read(flash->spi, cmd, 4, &sr1nv, 1);
  62 +       if (ret)
  63 +               return -EIO;
  64 +
  65 +       return spansion_is_locked_sr(flash, ofs, len, sr1nv);
  66 +}
  67 +
  68 +/*
  69 + * Lock a region of the flash. Compatible with Spansion s25fs-s family flash.
  70 + * Supports only the block protection bits BP{0,1,2} in the Status Register-1
  71 + * Non-Volatile(SR1NV).
  72 + *
  73 + * Sample table portion for 64MB flash (S25FS512S):
  74 + * Configuration Register-1 Non-Volatile(CR1NV[5])== 0
  75 + *
  76 + *  |  BP2  |  BP1  |  BP0  |  Prot Length  | Protected Portion
  77 + *  ------------------------------------------------------------
  78 + *  |   0   |   0   |   0   |  NONE          | NONE
  79 + *  |   0   |   0   |   1   |  1  MB         | Upper 1/64
  80 + *  |   0   |   1   |   0   |  2  MB         | Upper 1/32
  81 + *  |   0   |   1   |   1   |  4  MB         | Upper 1/16
  82 + *  |   1   |   0   |   0   |  8  MB         | Upper 1/8
  83 + *  |   1   |   0   |   1   |  16 MB         | Upper 1/4
  84 + *  |   1   |   1   |   0   |  32 MB         | Upper 1/2
  85 + *  |   1   |   1   |   1   |  64 MB         | ALL
  86 + *
  87 + * When CR1NV[5] == 1, the Lower memory array are protected.
  88 + *
  89 + * Returns negative on errors, 0 on success.
  90 + */
  91 +int spansion_lock(struct spi_flash *flash, u32 ofs, size_t len)
  92 +{
  93 +       u8 status_old, status_new;
  94 +       u8 mask = SR_BP2 | SR_BP1 | SR_BP0;
  95 +       u8 shift = ffs(mask) - 1, pow, val;
  96 +       int ret;
  97 +       u8 cmd[4];
  98 +       u32 sr1nv_offset = 0x0;
  99 +       u8 sr1nv;
 100 +
 101 +       cmd[0] = CMD_SPANSION_RDAR;
 102 +       cmd[1] = sr1nv_offset >> 16;
 103 +       cmd[2] = sr1nv_offset >> 8;
 104 +       cmd[3] = sr1nv_offset >> 0;
 105 +
 106 +       ret = spi_flash_cmd_read(flash->spi, cmd, 4, &sr1nv, 1);
 107 +       if (ret)
 108 +               return -EIO;
 109 +       status_old = sr1nv;
 110 +
 111 +       /* SPI NOR always locks to the end */
 112 +       if (ofs + len != flash->size) {
 113 +               /* Does combined region extend to end? */
 114 +               if (!stm_is_locked_sr(flash, ofs + len, flash->size - ofs - len,
 115 +                                     status_old))
 116 +                       return -EINVAL;
 117 +               len = flash->size - ofs;
 118 +       }
 119 +
 120 +       /*
 121 +        * Need smallest pow such that:
 122 +        *
 123 +        *   1 / (2^pow) <= (len / size)
 124 +        *
 125 +        * so (assuming power-of-2 size) we do:
 126 +        *
 127 +        *   pow = ceil(log2(size / len)) = log2(size) - floor(log2(len))
 128 +        */
 129 +       pow = ilog2(flash->size) - ilog2(len);
 130 +       val = mask - (pow << shift);
 131 +       if (val & ~mask)
 132 +               return -EINVAL;
 133 +
 134 +       /* Don't "lock" with no region! */
 135 +       if (!(val & mask))
 136 +               return -EINVAL;
 137 +
 138 +       status_new = (status_old & ~mask) | val;
 139 +
 140 +       /* Only modify protection if it will not unlock other areas */
 141 +       if ((status_new & mask) <= (status_old & mask))
 142 +               return -EINVAL;
 143 +
 144 +       cmd[0] = CMD_SPANSION_WRAR;
 145 +       ret = spi_flash_cmd_write(flash->spi, cmd, 4, &status_new, 1);
 146 +       if (ret)
 147 +               return -EIO;
 148 +
 149 +       return 0;
 150 +}
 151 +
 152 +/*
 153 + * Unlock a region of the flash. See spansion_lock() for more info
 154 + *
 155 + * Returns negative on errors, 0 on success.
 156 + */
 157 +int spansion_unlock(struct spi_flash *flash, u32 ofs, size_t len)
 158 +{
 159 +       uint8_t status_old, status_new;
 160 +       u8 mask = SR_BP2 | SR_BP1 | SR_BP0;
 161 +       u8 shift = ffs(mask) - 1, pow, val;
 162 +       int ret;
 163 +
 164 +       u8 cmd[4];
 165 +       u32 sr1nv_offset = 0x0;
 166 +       u8 sr1nv;
 167 +
 168 +       cmd[0] = CMD_SPANSION_RDAR;
 169 +       cmd[1] = sr1nv_offset >> 16;
 170 +       cmd[2] = sr1nv_offset >> 8;
 171 +       cmd[3] = sr1nv_offset >> 0;
 172 +
 173 +       ret = spi_flash_cmd_read(flash->spi, cmd, 4, &sr1nv, 1);
 174 +       if (ret)
 175 +               return -EIO;
 176 +       status_old = sr1nv;
 177 +
 178 +       /* Cannot unlock; would unlock larger region than requested */
 179 +       if (spansion_is_locked_sr(flash, ofs - flash->erase_size, flash->erase_size,
 180 +                            status_old))
 181 +               return -EINVAL;
 182 +       /*
 183 +        * Need largest pow such that:
 184 +        *
 185 +        *   1 / (2^pow) >= (len / size)
 186 +        *
 187 +        * so (assuming power-of-2 size) we do:
 188 +        *
 189 +        *   pow = floor(log2(size / len)) = log2(size) - ceil(log2(len))
 190 +        */
 191 +       pow = ilog2(flash->size) - order_base_2(flash->size - (ofs + len));
 192 +       if (ofs + len == flash->size) {
 193 +               val = 0; /* fully unlocked */
 194 +       } else {
 195 +               val = mask - (pow << shift);
 196 +               /* Some power-of-two sizes are not supported */
 197 +               if (val & ~mask)
 198 +                       return -EINVAL;
 199 +       }
 200 +       status_new = (status_old & ~mask) | val;
 201 +
 202 +       /* Only modify protection if it will not lock other areas */
 203 +       if ((status_new & mask) >= (status_old & mask))
 204 +               return -EINVAL;
 205 +
 206 +       cmd[0] = CMD_SPANSION_WRAR;
 207 +       ret = spi_flash_cmd_write(flash->spi, cmd, 4, &status_new, 1);
 208 +       if (ret)
 209 +               return -EIO;
 210 +
 211 +       return 0;
 212 +}
 213 +#endif
 214
 215  #ifdef CONFIG_SPI_FLASH_MACRONIX
 216  static int spi_flash_set_qeb_mxic(struct spi_flash *flash)
 217 @@ -1132,6 +1319,13 @@ int spi_flash_scan(struct spi_flash *flash)
 218                 flash->flash_is_locked = stm_is_locked;
 219  #endif
 220                 break;
 221 +#if defined(CONFIG_SPI_FLASH_SPANSION)
 222 +       case SPI_FLASH_CFI_MFR_SPANSION:
 223 +               flash->flash_lock = spansion_lock;
 224 +               flash->flash_unlock = spansion_unlock;
 225 +               flash->flash_is_locked = spansion_is_locked;
 226 +#endif
 227 +               break;
 228         default:
 229                 debug("SF: Lock ops not supported for %02x flash\n", idcode[0]);
 230         }
 231 --
 232 1.7.9.5
 233