[U-Boot-Users] NAND driver question

Stefan Roese
2008-01-30T07:45:05Z

On Tuesday 29 January 2008, Craig Millen wrote:
> I have been experiencing a few problems when using a NAND flash for
> storage in u-boot.
>
> When I'm reading large files (7MB) from the NAND, periodically there
> will be a NAND ECC read error when using the following command:
>
> => nand read 400000 0 154000
> NAND read: device 0 offset 0x0, size 0x154000 1392640 bytes read:
> ERROR.
>
> After turning on debug, the problem is occurring in the nand_read_ecc
> function whereby the ecc check fails. After running it numerous times,
> there seems to be no correlation between pages that fail and appears to
> be completely random.
> Has anyone else had these problems?

No. NAND blocks can fail and generate ECC errors. But your description doesn't
really sound like this is a NAND chips related problem. Does this happen on
multiple boards or just s single one? This looks more like a timing problem
or something like this to me.

IIRC, then you had to change the 4xx NDFC driver to access the NAND via 8bit
access, correct? I have used this driver on multiple 4xx boards and on all
boards this driver can be used as is, meaning with 32bit access enabled.
Perhaps you still have a problem with the interface to the NAND chips.

> Furthermore, the "nand write" command doesn't skip bad blocks. Are you
> supposed to use a different command to write files to the NAND that
> skips the bad blocks?

As already mentioned the .jffs2" extension is what you want. ".i" for "image"
should do too.

Best regards,
Stefan

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