This is a new VIA chipset that works with the existing code. It only needs the device id to be added for detection.
Created attachment 12515 [details] add P4M900 device id to via-agp
Please submit patches via email. This one should be sent to Dave Airlie <airlied@linux.ie> Andrew Morton <akpm@linux-foundation.org> linux-kernel@vger.kernel.org Thanks.