On Tuesday 08 May 2007, Vitaly Wool wrote:
> On 5/8/07, David Goodenough <david.goodenough@linkchoose.co.uk> wrote:
> > I have no idea what data is in the OOB data, I have never met a
> > tool that would show me.  Can you tell me how to read it?
>
> Please use nanddump.
>
> > As I said later in the note to which you replied, Microtik do
> > ship a version of Yaffs suitable for linux 2.4, I am trying to
> > get it to work with Linux 2.6.19+.  I have no idea what licences
> > Microtik have from Aleph1, I presume that they have one for their
> > boot loader.  The point however is that Yaffs on 2.6.16 and below
> > work, that with 2.6.19 seem not to - or I have not found the right
> > combination of options.  Resolving this is the point of my question.
>
> Since 2.6.18, the whole MTD susbystem in kernel has been reworked quite a
> bit. Can you please provide the OOB dumps for the working case?
> I guess BTW, that since you were using 2.4, your NAND chip has 512b
> page. Is that correct?
>
> Thanks,
>    Vitaly

It is the transition to 2.6.19 that I am interested in.  I am trying
to have a system using 2.6.19 which can be read by a system built using
the old Yaffs does the ECC and manages the OOB environment - i.e the 
bootloader.

I am currently building a version of nanddump inside OpenWrt and I will
report on that when I get it working.

Yes, the code shipped by Microtik was for 512b pages.  In fact it was not
even Yaffs2, it was Yaffs1.  But they have updated the bootloader to handle
larger page sizes (which meant OpenWrt upgrading to Yaffs2 with 2.6.16)
and that worked on the RB532 for both small and larger page sizes.  

The box I am using (an early RB112) has the same chip as was used in the
RB532 (a Hynix chip), and so should work with either version of the code.
For some reason which I have not been able to solve and which when raised
on the Microtik forum they never answered, I am unable to upgrade the 
bootloader to the very latest version, but it is supposed to be a version
that includes the large page size support (I am running 1.9, the large
page size was added in 1.3 and the latest is 2.7).

David