drm/i915/xelpd: First stab at DPT support
Add support for DPT (display page table). DPT is a slightly peculiar two level page table scheme used for tiled scanout buffers (linear uses direct ggtt mapping still). The plane surface address will point at a page in the DPT which holds the PTEs for 512 actual pages. Thus we require 1/512 of the ggttt address space compared to a direct ggtt mapping. We create a new DPT address space for each framebuffer and track two vmas (one for the DPT, another for the ggtt). TODO: - Is the i915_address_space approaach sane? - Maybe don't map the whole DPT to write the PTEs? - Deal with remapping/rotation? Need to create a separate DPT for each remapped/rotated plane I guess. Or else we'd need to make the per-fb DPT large enough to support potentially several remapped/rotated vmas. How large should that be? Signed-off-by:Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by:
Bommu Krishnaiah <krishnaiah.bommu@intel.com> Cc: Wilson Chris P <Chris.P.Wilson@intel.com> Cc: Tang CQ <cq.tang@intel.com> Cc: Auld Matthew <matthew.auld@intel.com> Reviewed-by:
Uma Shankar <uma.shankar@intel.com> Reviewed-by:
Wilson Chris P <Chris.P.Wilson@intel.com> Signed-off-by:
Imre Deak <imre.deak@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20210506161930.309688-5-imre.deak@intel.com
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bdd27cad
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