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From: vimal singh <vimal.newwork@gmail.com>
Date: Fri, 21 Aug 2009 10:47:09 +0530
Message-ID: <ce9ab5790908202217t2430646co5059f308a23d7397@mail.gmail.com>
Subject: Re: [U-Boot] NAND ECC Error with wrong SMC ording bug
To: Sean MacLennan <smaclennan@pikatech.com>
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Cc: u-boot@lists.denx.de, Stefan Roese <sr@denx.de>, Feng Kan <fkan@amcc.com>,
	linux-mtd@lists.infradead.org, linuxppc-dev@ozlabs.org
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<snip>

> With the current ndfc code, the error correction gets the bits wrong.
> Switching it back to the original way and the correction is correct.
>
> diff --git a/drivers/mtd/nand/ndfc.c b/drivers/mtd/nand/ndfc.c
> index 89bf85a..497e175 100644
> --- a/drivers/mtd/nand/ndfc.c
> +++ b/drivers/mtd/nand/ndfc.c
> @@ -101,9 +101,8 @@ static int ndfc_calculate_ecc(struct mtd_info *mtd,
>
> =A0 =A0 =A0 =A0wmb();
> =A0 =A0 =A0 =A0ecc =3D in_be32(ndfc->ndfcbase + NDFC_ECC);
> - =A0 =A0 =A0 /* The NDFC uses Smart Media (SMC) bytes order */
> - =A0 =A0 =A0 ecc_code[0] =3D p[2];
> - =A0 =A0 =A0 ecc_code[1] =3D p[1];
> + =A0 =A0 =A0 ecc_code[0] =3D p[1];
> + =A0 =A0 =A0 ecc_code[1] =3D p[2];
> =A0 =A0 =A0 =A0ecc_code[2] =3D p[3];
>
> =A0 =A0 =A0 =A0return 0;
>
> Does anybody see a problem with my method of reproducing the bug? This
> bug is deadly for our customers. I don't want to make the change unless
> it is absolutely necessary..

Just one question: did you enabled MTD_NAND_ECC_SMC in configs?

-vimal

>
> Cheers,
> =A0 Sean
>
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>