Re: UbiFS + HWECC(?) + BeagleBoard = fail

[Charles Manning <manningc2@actrix.gen.nz>]

On Thursday 09 December 2010 21:30:48 Luca Ceresoli wrote:
> Charles Manning wrote:
> > Luca, I have been having similar problems on a hacked Overo kernel.
> >
> > I have no problems with 2.6.35.
> >
> > I tried just commenting out the define and disabling PREFETCH and did not
> > get a good boot due to ubi not finding the volume info.
> >
> > Are you loading up a UBI image with uboot?
> >
> > Are you using the ubi volume as rootfs?
>
> To make it work again, I did from u-boot:
> - nand scrub (*completely* wipe the NAND)
> - ubi part nand0,3 (recreate partitions)
> - ubi create rootfs 400000
> - ...create other partitions...
> - ubi write ... (to rewrite rootfs)
> - finally, boot with the kernel having the define commented and PREFETCH
> off.
>
> Not all of these may be needed, but this way I got the board up and running
> again.
>
> Luca

What branch are you working from?

I tried working from a reasonably recent master on 
git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6.git

I found that reads via the  prefetch eengine work, but reads via 
        ioread16_rep(nand->IO_ADDR_R, buf, len / 2)
do not.

Perhaps this is due to the address not being set up properly. Any clues?

I found that I can make everything work by realigning all accesses in 
nand_base.c to be 4-byte aligned.


-- Charles