[U-Boot] NAND flash question

[Peter Barada]

On 09/19/2013 04:04 PM, ANDY KENNEDY wrote:
> All,
>
> We have a design that has NAND as a secondary device (not the boot
> device).  The last four pages of the NAND flash are reported as bad.
> Should this be true for all NAND flash devices we have?
>
>
No, I wouldn't think so.  Manufacturers qualify their parts and mark bad
blocks found during qualification testing.  Most data sheets indicate
that the number of bad blocks marked bad during manufacturer is below a
set percentage(if above thent he part is rejected).  Some parts that are
meant to be used during boot (such as NAND meant for OMAP parts) will
have certain blocks that are guaranteed good (i.e. the boot blocks). 
Past that bad blocks could be anywhere in a particular device.

-- 
Peter Barada
peter.barada at logicpd.com