[timr at probo.com: Re: XFree86 5.0]

[Olaf Hering]

Hi,


this one is about the appearently wrong pci layout on some pSeries
systems. I'm pretty sure that there are cases where the graphics card is
on a bus number > 256, probably a p660.
In this case, its a p630.

What is wrong in this picture?


Gruss Olaf

----- Forwarded message from Tim Roberts <timr at probo.com> -----

Date: Wed, 28 Aug 2002 09:22:37 -0700
Subject: Re: XFree86 5.0
From: "Tim Roberts" <timr at probo.com>
To: "devel at xfree86.org" <devel at xfree86.org>

On Wed, 28 Aug 2002 17:56:28 +0200, Olaf Hering wrote:

>begin  On Wed, Aug 28, Marc Aurele La France wrote:
>
>> On Wed, 28 Aug 2002, Olaf Hering wrote:
>>
>> > I'm not a member, just a user.
>> > But if that one can be fixed in a clean way, what would help alot, it is
>> > perhaps related to the pci domain stuff:
>>
>> > ./programs/Xserver/hw/xfree86/os-support/bus/Pci.h
>> > ...
>> > #define MAX_PCI_BUSES   256     /* Max number of PCI buses           */
>> > ...
>>
>> > Real life example:
>>
>> > 102:00.0 VGA compatible controller: Matrox Graphics, Inc. MGA G400 AGP
(rev 85)
>>
>> As per the PCI specs, a tag has only 8 bits for the bus number.   What
>> architecture/OS is this?
>
>I have never read the PCI spec, I wish I had...
>...
>Are you really sure that this bus number 0x102 should never happen?

Yes.  The bus number field in the CONFIG_ADDRESS register, which is used to
address PCI configuration requests, is 8 bits wide.  The bus number field in
the configuration space of a PCI-to-PCI bridge, which is the only way to
ASSIGN a bus number to a specific bus, is also 8 bits wide.

I have no idea what the "102" might mean, unless this machine us using bit 8
to signal AGP vs PCI.  That would be wrong.

--
- Tim Roberts, timr at probo.com
  Providenza & Boekelheide, Inc.


----- End forwarded message -----

--
 $ man clone

BUGS
       Main feature not yet implemented...

** Sent via the linuxppc64-dev mail list. See http://lists.linuxppc.org/