I often get fffe's when wanting to read SDRAM which has been changed by other processors between local write and read accesses. It's because I forgot to turn cache on PPC off.
You should always turn off cache when accessing shared memory regions or for any kind of RAM tests as well.
Strange values are there because you can not say anything specific about current cache coherency.
regards,
Matevz
> ----------
> From: Mathieu Berland - 77160[SMTP:MATHIEU.BERLAND@EADS-TELECOM.COM]
> Sent: Tuesday, June 25, 2002 1:58:43 PM
> To: pci-sig@znyx.com
> Cc: pci-sig@znyx.com
> Subject: Re: word mismatch
> Auto forwarded by a Rule
>
I can display memory at any time on the add-on card or on the monarch
board, I have always the same result. It works if I do on the add-on
card a operation like "word = word". What about cache ? Why a mismatch
on only one word ?