Re: BAR Allocations

["Peter Marek" <peter.marek@marekmicro.de>]

Tony,

the only situation when I have seen such a behaviouir is when the BIOS runs
out of ressources. That's why the command register stays disabled. The BIOS
knows that it hasn't configured the card properly. But for some reason it
can't assign ressources to it. One common problem is that you request to
much memory below the 1 MEG boundary or too much IO address space. In
industrial applications some BIOS's have problems configuring systems with a
huge number of slots, containing multiple P2P bridges.


Regards,

Peter Marek
General Director
MarekMicro GmbH
Kropfersrichter Str. 6-8
D-92237 Sulzbach-Rosenberg
Germany
Phone: 049 - 9661 - 908 - 210
Fax:      049 - 9661 - 908 - 100
----- Original Message -----
From: Tony Goodfellow <tonyg@1pdc.com>
To: 'pci-sig' <pci-sig@znyx.com>
Sent: Saturday, April 08, 2000 3:59 AM
Subject: BAR Allocations


> Does Anyone have experience of certain motherboard BIOS's incorrectly
> configuring BARs.
> We have had an experience where the motherboard has allocated a Memory
> Mapped Register BAR to
> 0h!. The same BIOS allocates 0h to the PROM Address BAR. The command
> register is left as 0h, thus we are not turned on. We can see the BIOS
> accessing the BARs etc using an analyzer.
> Any help would be appreciated.