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From: Vladimir Barinov <vbarinov@embeddedalley.com>
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To: Holger Schurig <h.schurig@mn-solutions.de>
Subject: Re: [PATCH] [MTD] MXC NAND driver fixes (v3)
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Hello Holger,

Could you explain how this message is related to this thread?
This patch as well as linux-mtd mail list doesn't care about platform 
specific code that you can do in your custom mx21 based board.

Holger Schurig wrote:
> Hmm, in u-boot v2, drivers/nand/nand_imx.c, I read:
>
>
> /*
>  * MX21 Hardware contains a bug which causes HW ECC to fail for two
>  * consecutive read pages containing 1bit Errors (See MX21 Chip Erata,
>  * Erratum 16). Use software ECC for this chip.
>  */
>
> BTW, in my version of MC9328MX21CE.pdf it's number 18.
>
>
> Do you know if all I need on i.MX21 is then
>
> static struct mxc_nand_platform_data nand_board_info = {
>        .width = 1,
>        .hw_ecc = 0,  /* Broken hardware */
> };
>   
Great, so the current mxc_nand driver can support your imx21 cpu through 
platform data.

Regarding to me then I use mx27 cpu and it's errata taken from FSL site 
says nothing about HW ECC:
http://www.freescale.com/files/32bit/doc/errata/MCIMX27CE.pdf?fsrch=1
nor in addendum:
http://www.freescale.com/files/dsp/doc/ref_manual/MCIMX27RMAD.pdf?fsrch=1

I can successfully flash jffs2 image to NAND flash, mount and read the 
context.
Ditto I can do with ubifs. All this with hw_ecc = 1.

Regards,
Vladimir