Re: [PATCH] disable CPU side GART accesses

Dave Airlie
2008-10-29T21:40:46Z

On Thu, Oct 30, 2008 at 7:32 AM, Dave Jones <davej@redhat.com> wrote:
> On Thu, Oct 30, 2008 at 07:24:34AM +1000, Dave Airlie wrote:
>
> > This stops the CPU from using the aperture for most DRI things. I
> > can't confirm this won't regress working systems
> > though. The whole AMD GART thing scares me, esp if some of the host
> > chipsets also have an AGP GART.
>
> The easy cop-out for those in the past has been 'dont support them'.
> It's why we removed some K8 chipset PCI IDs from the via driver for eg.
> iirc, if we leave them unprogrammed, they're essentially irrelevant.
>

I was more going the other way, why use the IOMMU for AGP when it has
other tasks to
do, and we have a host chipset GART.

Granted I've never had an AMD + AGP system to ever care about this.

Dave.