[U-Boot] [PATCH 1/1] ppc4xx: Fix ECC Correction bug with SMC ordering for NDFC driver

[U-Boot] [PATCH 1/1] ppc4xx: Fix ECC Correction bug with SMC ordering for NDFC driver

[Feng Kan]

Fix ECC Correction bug where the byte offset location were double
flipped causing correction routine to toggle the wrong byte location
in the ECC segment. The ndfc_calculate_ecc routine change the order
of getting the ECC code.
        /* The NDFC uses Smart Media (SMC) bytes order */
        ecc_code[0] = p[2];
        ecc_code[1] = p[1];
        ecc_code[2] = p[3];
But in the Correction algorithm when calculating the byte offset
location, the s1 is used as the upper part of the address. Which
again reverse the order making the final byte offset address 
location incorrect.
	byteoffs = (s1 << 0) & 0x80;
	.
	.
	byteoffs |= (s0 >> 4) & 0x08;
The order is change to read it in straight and let the correction
function to revert it to SMC order.

Signed-off-by: Feng Kan <fkan@amcc.com>
Acked-by: Victor Gallardo <vgallardo@amcc.com>
Acked-by: Prodyut Hazarika <phazarika@amcc.com>
---
 drivers/mtd/nand/ndfc.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/mtd/nand/ndfc.c b/drivers/mtd/nand/ndfc.c
index 528b22b..0891936 100644
--- a/drivers/mtd/nand/ndfc.c
+++ b/drivers/mtd/nand/ndfc.c
@@ -89,8 +89,8 @@ static int ndfc_calculate_ecc(struct mtd_info *mtdinfo,
 
 	/* The NDFC uses Smart Media (SMC) bytes order
 	 */
-	ecc_code[0] = p[2];
-	ecc_code[1] = p[1];
+	ecc_code[0] = p[1];
+	ecc_code[1] = p[2];
 	ecc_code[2] = p[3];
 
 	return 0;
-- 
1.5.5

[U-Boot] [PATCH 1/1] ppc4xx: Fix ECC Correction bug with SMC ordering for NDFC driver

[Stefan Roese]

On Friday 21 August 2009 19:59:42 Feng Kan wrote:
> Fix ECC Correction bug where the byte offset location were double
> flipped causing correction routine to toggle the wrong byte location
> in the ECC segment. The ndfc_calculate_ecc routine change the order
> of getting the ECC code.
>         /* The NDFC uses Smart Media (SMC) bytes order */
>         ecc_code[0] = p[2];
>         ecc_code[1] = p[1];
>         ecc_code[2] = p[3];
> But in the Correction algorithm when calculating the byte offset
> location, the s1 is used as the upper part of the address. Which
> again reverse the order making the final byte offset address
> location incorrect.
> 	byteoffs = (s1 << 0) & 0x80;
> 	.
> 	.
> 	byteoffs |= (s0 >> 4) & 0x08;
> The order is change to read it in straight and let the correction
> function to revert it to SMC order.
>
> Signed-off-by: Feng Kan <fkan@amcc.com>
> Acked-by: Victor Gallardo <vgallardo@amcc.com>
> Acked-by: Prodyut Hazarika <phazarika@amcc.com>

Applied to u-boot-ppc4xx/master. Thanks.

Cheers,
Stefan

--
DENX Software Engineering GmbH,      MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich,  Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-0 Fax: (+49)-8142-66989-80 Email: office at denx.de