FROMGIT: drm/i915/icl: avoid unclaimed PLANE_NV12_BUF_CFG register

We don't have proper watermark NV12 support on ICL due to differences
in how it should be implemented. In commit 234059da0f33
("drm/i915/icl: NV12 y-plane ddb is not in same plane") we avoided
writing the non-existent PLANE_NV12_BUF_CFG registers but we forgot to
also avoid them on the hardware state readout. While the code is still
not correct, at least now we can avoid unclaimed register error
messages when dealing with RGB formats, which makes CI happier.

Also add some FIXME comments in order to make it even more clear that
there's still work to do.

References: commit 234059da0f33 ("drm/i915/icl: NV12 y-plane ddb is
 not in same plane")
Cc: Mahesh Kumar <mahesh1.kumar@intel.com>
Reviewed-by: Mahesh Kumar <mahesh1.kumar@intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180801004614.22149-1-paulo.r.zanoni@intel.com
(cherry picked from commit 12a6c931beffeaaa350ef562e91e49918b4b3e68
 git://anongit.freedesktop.org/drm-intel drm-intel-next)

BUG=b:114114103
TEST=No unclaimed reg debug warning during boot ICL eDP

Change-Id: I24508ca4750e5b4da6b7bf10477bb707592335af
Signed-off-by: Vidya Srinivas <vidya.srinivas@intel.com>
Signed-off-by: Rajat Jain <rajatja@google.com>
Reviewed-on: https://chromium-review.googlesource.com/1218542
Reviewed-by: Rajat Jain <rajatja@chromium.org>
Reviewed-by: Stéphane Marchesin <marcheu@chromium.org>
Commit-Queue: Rajat Jain <rajatja@chromium.org>
Trybot-Ready: Rajat Jain <rajatja@chromium.org>
Tested-by: Rajat Jain <rajatja@chromium.org>
1 file changed