For whatever reason, MI_DISPLAY_FLIP fails to change tiling mode on
Baytrail, so just use CPU driven mmio flips instead.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=76176 Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>