[PATCH v3 3/9] drm: Update drm_addmap and drm_mmap to use PAT WC instead of MTRRs

[Dave Airlie]

On Tue, May 14, 2013 at 9:58 AM, Andy Lutomirski <luto at amacapital.net> wrote:
> Previously, DRM_FRAME_BUFFER mappings, as well as DRM_REGISTERS
> mappings with DRM_WRITE_COMBINING set, resulted in an unconditional
> MTRR being added but the actual mappings being created as UC-.
>
> Now these mappings have the MTRR added only if needed, but they will
> be mapped with pgprot_writecombine.
>
> The non-WC DRM_REGISTERS case now uses pgprot_noncached instead of
> hardcoding the bit twiddling.
>
> The DRM_AGP case is unchanged for now.

Just FYI this breaks on powerpc build, I've fixed it up and pushed the
fixed version to
drm-next-staging, I'll push that to drm-next in a couple of days, once
kbuild robot hits it.

Dave.