Re: [PATCH v2 00/14] OMAP-GPMC related cleanup for common zImage

Tony Lindgren
2012-10-16T18:06:01Z

* Ivan Djelic <ivan.djelic@parrot.com> [121010 09:40]:
>
> I ran several mtd regression tests on a Beagle Board on your gpmc-czimage-v2 tag.
> All BCH error correcting tests passed successfully.
>
> I occasionally had weird read errors though, especially when reading blank pages:
> the omap driver returned 512-byte sectors containing something like:
>
> 30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff
> 30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff
> 30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff
> 30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff
> 30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff
> 30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ff30ffffffffff
> ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
> ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
> ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
> ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
> ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
> ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
> ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
> ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
> ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
> ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
>
> instead of:
>
> ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
> ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
> ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
> ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
> ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
> ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
> ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
> ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
> ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
> ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
> ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
> ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
> ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
> ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
> ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
> ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff
>
> I was able to reproduce the problem also on l2-mtd tip, albeit less often.
> The problem seems to occur quite randomly, it may be a hardware issue on
> my board...

Things like this typically happen in the GPMC timings are not correct.
Maybe add #define DEBUG to top of gpmc.c and compare the timings
before and after Afzal's patches?

> Anyway, the ECC handling part looks OK to me.

Regards,

Tony