unknown chip id FF

[nur]

First of all, i searched my problem through google.com
Infradead archive refers to wrong pages for a specific subject
I mean, i m clicking on "DOC 2000 driver (NFTL) in kernel 2.4.7" link but it
goes to "Porting FFS2 on MIPS subject"
So that, I couldn't find any comment about my problem.

I can boot my diskonchip millennium on a platform without any problem. DoCs
window address is e8000
The problem is that, I can't boot the same chip on another platform even
though I changed window address to e8000 from bios settings
If I boot from romdos, i can see the content of diskonchip. When I boot from
DoC it says, using configured probe address e8000... possible diskonchip
with unknown chip id FF found at E8000. So can't mount from DoC.
Any idea would be appreciated. Thanks in advance