[U-Boot] [U-Boot, U-boot, 2/2] mtd: nand: davinci: allow to change ecclayout by ecclayout command

[Scott Wood]

On Fri, May 16, 2014 at 09:26:37PM +0300, Khoronzhuk, Ivan wrote:
> From: WingMan Kwok <w-kwok2 at ti.com>
> 
> This patch adds opportunity to change ecclayout of current nand
> device during runtime. So we can change the current nand device
> ecclayout using the "nand ecclayout set" command before writing
> the data to nand flash.
> 
> Signed-off-by: Hao Zhang <hzhang at ti.com>
> Signed-off-by: WingMan Kwok <w-kwok2 at ti.com>
> Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk at ti.com>
> 
> ---
> drivers/mtd/nand/davinci_nand.c | 101 ++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 101 insertions(+)
> 
> diff --git a/drivers/mtd/nand/davinci_nand.c b/drivers/mtd/nand/davinci_nand.c
> index 75b03a7..b33de0d 100644
> --- a/drivers/mtd/nand/davinci_nand.c
> +++ b/drivers/mtd/nand/davinci_nand.c
> @@ -306,6 +306,103 @@ static struct nand_ecclayout nand_davinci_4bit_layout_oobfirst = {
>  #endif
>  };
>  
> +#if defined(CONFIG_CMD_NAND_ECCLAYOUT)
> +#if defined(CONFIG_SYS_NAND_PAGE_2K)

Undocumented CONFIG symbol (yes, I know it's not new)... Also redundant
with CONFIG_SYS_NAND_PAGE_SIZE (though that's only documented in the
context of SPL).

> +static struct nand_ecclayout nand_keystone_rbl_4bit_layout_oobfirst = {
> +	.eccbytes = 40,
> +	.eccpos = {
> +		6, 7,
> +		8, 9, 10, 11, 12, 13, 14, 15,
> +		22, 23,
> +		24, 25, 26, 27, 28, 29, 30, 31,
> +		38, 39,
> +		40, 41, 42, 43, 44, 45, 46, 47,
> +		54, 55,
> +		56, 57, 58, 59, 60, 61, 62, 63,
> +	},

Why the odd 2/8 pattern?

> +	.oobfree = {
> +		{.offset = 2, .length = 4, },
> +		{.offset = 16, .length = 6, },
> +		{.offset = 32, .length = 6, },
> +		{.offset = 48, .length = 6, },
> +	},
> +};
> +#elif defined(CONFIG_SYS_NAND_PAGE_4K)
> +static struct nand_ecclayout nand_keystone_rbl_4bit_layout_oobfirst = {
> +	.eccbytes = 80,
> +	.eccpos = {
> +		6, 7,
> +		8, 9, 10, 11, 12, 13, 14, 15,
> +		22, 23,
> +		24, 25, 26, 27, 28, 29, 30, 31,
> +		38, 39,
> +		40, 41, 42, 43, 44, 45, 46, 47,
> +		54, 55,
> +		56, 57, 58, 59, 60, 61, 62, 63,
> +		70, 71,
> +		72, 73, 74, 75, 76, 77, 78, 79,
> +		86, 87,
> +		88, 89, 90, 91, 92, 93, 94, 95,
> +		102, 103,
> +		104, 105, 106, 107, 108, 109, 110, 111,
> +		118, 119,
> +		120, 121, 122, 123, 124, 125, 126, 127,
> +		},
> +	.oobfree = {
> +		{.offset = 2, .length = 4, },
> +		{.offset = 16, .length = 6, },
> +		{.offset = 32, .length = 6, },
> +		{.offset = 48, .length = 6, },
> +		{.offset = 64, .length = 6, },
> +		{.offset = 80, .length = 6, },
> +		{.offset = 96, .length = 6, },
> +		{.offset = 112, .length = 6, },
> +	},
> +};
> +#endif
> +
> +#define NAND_ECCLAYOUT_NUM 2
> +
> +struct nand_ecclayout *davinci_nand_ecclayouts[NAND_ECCLAYOUT_NUM] = {
> +	&nand_davinci_4bit_layout_oobfirst,
> +	&nand_keystone_rbl_4bit_layout_oobfirst,
> +};
> +
> +int board_nand_ecclayout_get_idx(struct nand_chip *nand,
> +				 struct nand_ecclayout *p)
> +{
> +	int i;
> +
> +	if (!p)
> +		return -1;
> +
> +	for (i = 0; i < NAND_ECCLAYOUT_NUM; i++)
> +		if (davinci_nand_ecclayouts[i] == p)
> +			return i;
> +
> +	return -1;
> +}

Use ARRAY_SIZE().

> +
> +struct nand_ecclayout *board_nand_ecclayout_get_layout(struct nand_chip *nand,
> +						       int idx)
> +{
> +	if ((idx >= 0) && (idx < NAND_ECCLAYOUT_NUM))
> +		return davinci_nand_ecclayouts[idx];
> +	else
> +		return NULL;
> +}
> +
> +int board_nand_ecclayout_set(struct nand_chip *nand, int idx)
> +{
> +	if (idx < 0 || idx >= NAND_ECCLAYOUT_NUM)
> +		return -1;
> +
> +	nand->ecc.layout = davinci_nand_ecclayouts[idx];
> +
> +	return 0;
> +}
> +#endif

Put a comment on this indicating what condition the #endif is ending.

>  static void nand_davinci_4bit_enable_hwecc(struct mtd_info *mtd, int mode)
>  {
>  	u32 val;
> @@ -631,7 +728,11 @@ void davinci_nand_init(struct nand_chip *nand)
>  	nand->ecc.calculate = nand_davinci_4bit_calculate_ecc;
>  	nand->ecc.correct = nand_davinci_4bit_correct_data;
>  	nand->ecc.hwctl = nand_davinci_4bit_enable_hwecc;
> +#ifndef CONFIG_CMD_NAND_ECCLAYOUT
>  	nand->ecc.layout = &nand_davinci_4bit_layout_oobfirst;
> +#else
> +	nand->ecc.layout = &nand_keystone_rbl_4bit_layout_oobfirst;
> +#endif

Use "ifdef/else" rather than "ifndef/else".

Why does enabling layout selection change the default layout?  Nothing in
the changelog suggests that.

-Scott