drm/i915: don't rewrite the GTT on resume v4
The BIOS shouldn't be touching this memory across suspend/resume, so
just leave it alone. This saves us ~6ms on resume on my T420 (retested
with write combined PTEs).
v2: change gtt restore default on pre-gen4 (Chris)
move needs_gtt_restore flag into dev_priv
v3: make sure we restore GTT on resume from hibernate (Daniel)
use opregion support as the cutoff for restore from resume (Chris)
v4: use a better check for opregion (Chris)
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
[danvet: Kill the needs_gtt_restore indirection and check directly for
OpRegion. Also explain in a comment what's going on.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
2 files changed