[Intel-gfx] [PATCH v4 0/2] drm/i915: SKL+ render decompression support

[ville.syrjala at linux.intel.com]

From: Ville Syrjälä <ville.syrjala at linux.intel.com>

Here's yet another iteration of CCS support.

The first major change is that we now treat fb->offsets[] as
raw byte offsets instead of linear offsets since that's what
userspace seems to want. This means we'll not allow non-tile
aligned offsets except with linear buffers. I still think
non-tile aligned offsets are potentially useful for planar
formats, but in order to support that we'd either need to
pretend that the non-aligned part of the offset is a linear
offset within the tile, or we'd need to deal with the actual
internal structure of the tile.

The other change is that we now use the LLC/eLLC hotspot
avoidance hash mode. The spec is super confusing when it comes
to documenting this. In places it claims that we needa to
align everything to 2MiB, but in other places it seems to be
telling us that we don't need to do that. I've tried to confirm
this empirically by randomizing the ppgtt address between
rendering to and sampling from the same compressed buffer,
and so far I've not seen any corruption. The only minor caveat
is that I've not tried this on a machine with eLLC.

Series available here:
git://github.com/vsyrjala/linux.git ccs_leftovers_2

Cc: Paulo Zanoni <paulo.r.zanoni at intel.com>
Cc: Daniel Vetter <daniel at ffwll.ch>
Cc: Ben Widawsky <ben at bwidawsk.net>
Cc: Jason Ekstrand <jason at jlekstrand.net>
Cc: Daniel Stone <daniels at collabora.com>

Ville Syrjälä (2):
  drm/i915: Implement .get_format_info() hook for CCS
  drm/i915: Add render decompression support

 drivers/gpu/drm/i915/i915_reg.h        |  29 +++
 drivers/gpu/drm/i915/intel_display.c   | 386 ++++++++++++++++++++++++++++-----
 drivers/gpu/drm/i915/intel_engine_cs.c |  13 ++
 drivers/gpu/drm/i915/intel_pm.c        |  29 ++-
 drivers/gpu/drm/i915/intel_sprite.c    |   5 +
 include/uapi/drm/drm_fourcc.h          |  20 ++
 6 files changed, 422 insertions(+), 60 deletions(-)

-- 
2.13.0