[U-Boot] [PATCH V2 2/3] mtd: nand: mxs check maximum ecc that platfrom supports

[Tim Harvey]

On Tue, Jul 21, 2015 at 1:15 AM, Peng Fan <Peng.Fan at freescale.com> wrote:
> Check maximum ecc strength for each platfrom to avoid the calculated ecc
> exceed the limitation.
>
> Signed-off-by: Peng Fan <Peng.Fan at freescale.com>
> Signed-off-by: Han Xu <b45815 at freescale.com>
> Reviewed-by: Marek Vasut <marex at denx.de>
> ---
>
> Changes v2:
>  Add Marek's reviewed by.
>
>  drivers/mtd/nand/mxs_nand.c | 9 ++++++++-
>  1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mtd/nand/mxs_nand.c b/drivers/mtd/nand/mxs_nand.c
> index 33ce817..97011b2 100644
> --- a/drivers/mtd/nand/mxs_nand.c
> +++ b/drivers/mtd/nand/mxs_nand.c
> @@ -149,6 +149,13 @@ static inline uint32_t mxs_nand_get_ecc_strength(uint32_t page_data_size,
>                                                 uint32_t page_oob_size)
>  {
>         int ecc_strength;
> +       int max_ecc_strength_supported;
> +
> +       /* Refer to Chapter 17 for i.MX6DQ, Chapter 18 for i.MX6SX */
> +       if (is_cpu_type(MXC_CPU_MX6SX))
> +               max_ecc_strength_supported = 62;
> +       else
> +               max_ecc_strength_supported = 40;
>
>         /*
>          * Determine the ECC layout with the formula:
> @@ -162,7 +169,7 @@ static inline uint32_t mxs_nand_get_ecc_strength(uint32_t page_data_size,
>                         / (galois_field *
>                            mxs_nand_ecc_chunk_cnt(page_data_size));
>
> -       return round_down(ecc_strength, 2);
> +       return min(round_down(ecc_strength, 2), max_ecc_strength_supported);
>  }
>
>  static inline uint32_t mxs_nand_get_mark_offset(uint32_t page_data_size,
> --
> 1.8.4
>

Tested on IMX6 with MT29F16G08 16Gb and MT29F2G08 2Gb NAND devices.

Tested-By: Tim Harvey <tharvey at gateworks.com>