I think there may be a problem in the yaffs mtdif, I'm hoping you guys can
verify.

1.  First off, since ECC is being done on the nand mtd level, YAFFs should
be looking at the return values of write_ecc and read_ecc to see if anything
has failed, currently that is not so in the mtdif.

2.  Second, looking at read_ecc in nand.c, it seems that an '(int)eccstatus'
is being added to the end of the oob_buf supplied after it is read... but
what that means is that the supplied oob_buf must be (16 + sizeof(int))
bytes (in my case 16+4=20).  I'm pretty sure YAFFS is only supplying an oob
buf that is 16 bytes.  This hasn't bitten me in the ass yet but it may one
day.  The bottom line is: I think the oob_buf in write_ecc is segmented in
16 bytes per chunk but the oob_buf in read_ecc is segmented into 20 bytes
per chunk.  Hopefully Thomas can shed some light on this.

Can someone please tell verify these things for me?

Thanks!

Christian

> -----Original Message-----
> From: Thomas Gleixner [mailto:tglx@linutronix.de]
> Sent: Wednesday, December 04, 2002 11:56 PM
> To: manningc2@actrix.gen.nz; Christian Gan; yaffs list
> Subject: Re: [YAFFS] Latest CVS ==> Interaction with mtd
>
>
> On Thursday 05 December 2002 00:25, Charles Manning wrote:
> > Nice to see things come together...
> >
> > Take a bow Thomas :-).
> Thanks.
> Also I know that I'm strongheaded some times. But at least I
> think we have a
> solution for everybody to live with. :)
>
> > On Thu, 05 Dec 2002 10:59, Christian Gan wrote:
> > > Wow... I finally got back onto getting a finalized version of YAFFS to
> > > ship with our board (www.guide-systems.com) and was about to get dirty
> > > with mods I had to make in earlier versions.  But lo and behold
> > > everything worked pretty much on the first compile with YAFFS, MTD and
> > > HWECC.
> COOL !
>
> --
> Thomas
> ____________________________________________________
> linutronix - competence in embedded & realtime linux
> http://www.linutronix.de
> mail: tglx@linutronix.de
>


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