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Re: Using wsdisplay from the Xserver

On Fri, Jan 23, 2009 at 10:36:48PM -0500, Michael wrote:
> Hash: SHA1
> Hello,
> in order to get rid of some of the PCI cruft in the Xserver and to  
> allow X to use more than one display device even when not using /dev/ 
> mem or something similar I started hacking it into using wsdisplay  
> ttys to find PCI-like video controllers instead of grubbing through / 
> dev/pci0
> This has the following advantages:
> - - we're going to find graphics controllers not visible through /dev/pci0
> - - we're going to see only graphics controllers
> - - X doesn't need to know about the actual bus structure at all
> - - X can mmap the right IO space for each individual device without  
> knowing about PCI domains, bus layout and whatnot - as far as X is  
> concerned each device can be in its own domain
> - - X doesn't need to know how to translate bus addresses to physical to  
> whatever - it could be completely agnostic regarding the actual PCI  
> bus setup

This has to be very well though to work on hardware like alpha, and other
hardware with non-linear mapping of I/O space (or whatever oddities
this hardware could have).

Manuel Bouyer <>
     NetBSD: 26 ans d'experience feront toujours la difference

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