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Date: Tue, 21 Oct 2003 16:42:30 -0600
From: Scott Long <scottl@freebsd.org>
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To: Eric Anholt <eta@lclark.edu>
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cc: current@freebsd.org
Subject: Re: PCI domains?
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Eric Anholt wrote:
> Is there any concept of PCI domains in the kernel?
> 
> This is for the DRM, while dealing with a complaint from Linus recently:
> 
> 
>>Please fix the fact that modern PCI is _not_ enumerated with just "bus,
>>slot, function". A lot of machines are starting to have a "domain number", 
>>which allows fro multiple independent PCI subsystems in the same machine.
>>
>>On linux, you can use "pci_name(pdev)" to get a truly unique descriptor of
>>the device (within the PCI subsystem). It will look something like
>>
>>	0000:00:02.0
>>
>>for "domain 0, bus 0, device 2, function 0".
> 
> 
> 

We don't have much of a concept of this (except possibly Alpha like John
mentioned, but I really cannot comment on that).  Supporting it
wouldn't be terribly magical on our end until we fix busdma to support
device-device transfers.  Since I don't know much context on the DRM
side, what exactly is Linus asking to change, and do we need to worry
about it?

Scott