If the entire device is powered off, we can safely assume that the
engine is also asleep (and idle).
Reported-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Fixes: a091d4ee ("drm/i915: Hold a wakeref for probing the ring registers")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180212093928.6005-1-chris@chris-wilson.co.uk