[PATCH v11 2/4] MTD: at91: add dt parameters for Atmel PMECC

[Richard Genoud]

2012/6/25 Josh Wu <josh.wu at atmel.com>:
> Add DT support for PMECC parameters.
>
> Signed-off-by: Hong Xu <hong.xu at atmel.com>
> Signed-off-by: Josh Wu <josh.wu at atmel.com>
> ---
>  .../devicetree/bindings/mtd/atmel-nand.txt         |    9 ++++
>  drivers/mtd/nand/atmel_nand.c                      |   52 +++++++++++++++++++-
>  2 files changed, 60 insertions(+), 1 deletion(-)
>
> diff --git a/Documentation/devicetree/bindings/mtd/atmel-nand.txt b/Documentation/devicetree/bindings/mtd/atmel-nand.txt
> index a200695..ed6927a 100644
> --- a/Documentation/devicetree/bindings/mtd/atmel-nand.txt
> +++ b/Documentation/devicetree/bindings/mtd/atmel-nand.txt
> @@ -16,6 +16,15 @@ Optional properties:
>  - nand-ecc-mode : String, operation mode of the NAND ecc mode, soft by default.
>   Supported values are: "none", "soft", "hw", "hw_syndrome", "hw_oob_first",
>   "soft_bch".
> +- atmel,has-pmecc : boolean to enable Programmable Multibit ECC hardware.
> +  Only supported by at91sam9x5 or later sam9 product.
> +- atmel,pmecc-cap : error correct capability for Programmable Multibit ECC
> +  Controller. Supported values are: 2, 4, 8, 12, 24.
> +- atmel,pmecc-sector-size : sector size for ECC computation. Supported values
> +  are: 512, 1024.
> +- atmel,pmecc-lookup-table-offset : includes two offsets of lookup table in ROM
> +  for different sector size. First one is for sector size 512, the next is for
> +  sector size 1024.
>  - nand-bus-width : 8 or 16 bus width if not present 8
>  - nand-on-flash-bbt: boolean to enable on flash bbt option if not present false
>
Maybe you should update the reg parameter documentation with the
needed resources.


> diff --git a/drivers/mtd/nand/atmel_nand.c b/drivers/mtd/nand/atmel_nand.c
> index 7a41a04..b97ad9f 100644
> --- a/drivers/mtd/nand/atmel_nand.c
> +++ b/drivers/mtd/nand/atmel_nand.c
> @@ -93,6 +93,11 @@ struct atmel_nand_host {
>
>        struct completion       comp;
>        struct dma_chan         *dma_chan;
> +
> +       bool                    has_pmecc;
> +       u8                      pmecc_corr_cap;
> +       u16                     pmecc_sector_size;
> +       u32                     pmecc_lookup_table_offset;
>  };
>
>  static int cpu_has_dma(void)
> @@ -481,7 +486,8 @@ static void atmel_nand_hwctl(struct mtd_info *mtd, int mode)
>  static int __devinit atmel_of_init_port(struct atmel_nand_host *host,
>                                         struct device_node *np)
>  {
> -       u32 val;
> +       u32 val, table_offset;
> +       u32 offset[2];
>        int ecc_mode;
>        struct atmel_nand_data *board = &host->board;
>        enum of_gpio_flags flags;
> @@ -517,6 +523,50 @@ static int __devinit atmel_of_init_port(struct atmel_nand_host *host,
>        board->enable_pin = of_get_gpio(np, 1);
>        board->det_pin = of_get_gpio(np, 2);
>
> +       host->has_pmecc = of_property_read_bool(np, "atmel,has-pmecc");
> +
> +       if (!(board->ecc_mode == NAND_ECC_HW) || !host->has_pmecc)
> +               return 0;       /* Not using PMECC */
> +
> +       /* use PMECC, get correction capability, sector size and lookup
> +        * table offset.
> +        */
> +       if (of_property_read_u32(np, "atmel,pmecc-cap", &val) != 0) {
> +               dev_err(host->dev, "Cannot decide PMECC Capability\n");
> +               return -EINVAL;
> +       } else if ((val != 2) && (val != 4) && (val != 8) && (val != 12) &&
> +           (val != 24)) {
> +               dev_err(host->dev,
> +                       "Unsupported PMECC correction capability: %d; should be 2, 4, 8, 12 or 24\n",
> +                       val);
> +               return -EINVAL;
> +       }
> +       host->pmecc_corr_cap = (u8)val;
> +
> +       if (of_property_read_u32(np, "atmel,pmecc-sector-size", &val) != 0) {
> +               dev_err(host->dev, "Cannot decide PMECC Sector Size\n");
> +               return -EINVAL;
> +       } else if ((val != 512) && (val != 1024)) {
> +               dev_err(host->dev,
> +                       "Unsupported PMECC sector size: %d; should be 512 or 1024 bytes\n",
> +                       val);
> +               return -EINVAL;
> +       }
> +       host->pmecc_sector_size = (u16)val;
> +
> +       if (of_property_read_u32_array(np, "atmel,pmecc-lookup-table-offset",
> +                       offset, 2) != 0) {
> +               dev_err(host->dev, "Cannot get PMECC lookup table offset\n");
> +               return -EINVAL;
> +       }
> +       table_offset = host->pmecc_sector_size == 512 ? offset[0] : offset[1];
> +
> +       if (!table_offset) {
> +               dev_err(host->dev, "Invalid PMECC lookup table offset\n");
> +               return -EINVAL;
> +       }
> +       host->pmecc_lookup_table_offset = table_offset;
> +
>        return 0;
>  }
>  #else
> --
> 1.7.9.5
>
>
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Richard.

-- 
for me, ck means con kolivas and not calvin klein... does it mean I'm a geek ?