KMS and TTM questions

James Simmons jsimmons at
Tue Oct 4 06:42:59 PDT 2011

> > Thats fine as long as you don't want to do acceleration or object
> > migration between GTT
> > and VRAM type memory. Now I expect when you give out this advice you
> Yes but the VIA doesn't if I recall correctly have any 'VRAM type memory'.
> It's all effectively in the GART with the 'stolen' pages preloaded into
> the translation tables by the BIOS at vga init time.
> It has fake VRAM type memory but thats really an illusion (although one
> the driver seems to like to keep up). The GEM changes do mean you can
> plug the existing allocator in the VIA driver into GEM directly. Whether
> that would be a good idea or not given the other things you then need to
> do I don't know - but it does seem to be me to be a stepping stone in the
> right direction that is much easier to make ?

That is correct. In fact the via driver detects what type of system ram is 
used so I can limit what resolutions are supported. Its possible that the 
memory doesn't have the bandwidth to support a very large resolution on 
older systems.

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