drm/i915/gtt: Don't restore the non-existent PDE for GGTT
authorChris Wilson <chris@chris-wilson.co.uk>
Fri, 1 Jun 2018 09:35:50 +0000 (10:35 +0100)
committerChris Wilson <chris@chris-wilson.co.uk>
Fri, 1 Jun 2018 13:53:40 +0000 (14:53 +0100)
commit3df845e7528b4f337e5cf91f3fd75610a646b259
tree427a1eab8515185c67146176dbed7dcc54e49138
parent37800ca8037adeeb1ccd23dc15f6452b395e3101
drm/i915/gtt: Don't restore the non-existent PDE for GGTT

On resume, we have to rewrite all the PDE entries for gen7 ppgtts. If we
switch on full-ppgtt, there is then one address space with no PDE, the
GGTT. Currently under aliasing-ppgtt, the GGTT address space does have
an associated ppgtt and so the restore works just fine. We would have a
similar problem if we tried disabling aliasing-ppgtt
(i915.enable_ppgtt=0). So skip the empty ppgtt, as being non-existent it
doesn't need restoring.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180601093554.13083-2-chris@chris-wilson.co.uk
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
drivers/gpu/drm/i915/i915_gem_gtt.c