On Thu, Apr 14, 2011 at 5:09 PM, Joerg Roedel <joro@xxxxxxxxxx> wrote: > On Thu, Apr 14, 2011 at 10:28:43AM -0400, Alex Deucher wrote: >> On Thu, Apr 14, 2011 at 4:56 AM, Joerg Roedel <joro@xxxxxxxxxx> wrote: >> > And this makes a difference, with this change on-top of -rc3 the box boots >> > fine. So there seems to be some dependency between the GART base and the GTT >> > base even when they are in different address spaces. >> > >> > Alex, can you comment on this? >> >> As Dave said, they are completely different addresses spaces. You >> could put the GPU aperture at 0 if you wanted (in fact we do on some >> chips). Perhaps there's some strange interaction with the nb gart >> since the nb gart on that chipset was designed to be used for graphics >> and the rs780/880 can be configured to use an agp aperture. >> Unfortunately, I'm not that familiar with the nb gart. > > Actually, the nb gart is part of the cpu. It is part of the cpu north > bridge and can translate io and cpu accesses. In fact, it is a remapper > of physical memory addresses. I know what it's for. In the IGP graphics chip is also part of the north bridge, but it may not be related at all. > > The problem seems to be related to specific gpu chips. On another > notebook with an hd3000 card gtt and the nb gart aperture are both on > 0xa0000000 too but the box works fine. I havn't tested with an hd5000 > yet. The failing notebook has an hd4200 mobility. What exact model is the hd3000? Is it IGP GPU or a discrete GPU? It it's an IGP, it's identical to the hd4200 programming-wise. > > Btw. what happens if the gpu accesses an unmapped address in the gtt > range? It's redirected to a dummy page. Alex _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
