[Intel-gfx] [PATCH] Revert "drm/i915: Use atomic commits for legacy page_flips"

[Chris Wilson]

This reverts commit ee042aa40b66d18d465206845b0752c6a617ba3f.

Something appears to be off in the timing, but as far as I can tell it
is not along the event delivery path. The net effect appears to be
rendering flicker (the current render buffer appears on the scanout,
with what appears to be active rendering for a fraction of a frame) and
is causing me a headache.

The cursor is also being stalled by page flips, causing a "heavy mouse"
and jitter.

Reported-and-tested-by: Steven Newbury <steve at snewbury.org.uk>
Reported-by:  Rafael Ristovski  <rafael.ristovski at gmail.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=96593
Testcase: igt/kms_cursor_legacy/basic-flip-vs-cursor
Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter at ffwll.ch>
Cc: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
---
 drivers/gpu/drm/i915/intel_display.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 1141b86..d4a7872 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -11646,7 +11646,6 @@ void intel_check_page_flip(struct drm_i915_private *dev_priv, int pipe)
 	spin_unlock(&dev->event_lock);
 }
 
-__maybe_unused
 static int intel_crtc_page_flip(struct drm_crtc *crtc,
 				struct drm_framebuffer *fb,
 				struct drm_pending_vblank_event *event,
@@ -14008,7 +14007,7 @@ static const struct drm_crtc_funcs intel_crtc_funcs = {
 	.set_config = drm_atomic_helper_set_config,
 	.set_property = drm_atomic_helper_crtc_set_property,
 	.destroy = intel_crtc_destroy,
-	.page_flip = drm_atomic_helper_page_flip,
+	.page_flip = intel_crtc_page_flip,
 	.atomic_duplicate_state = intel_crtc_duplicate_state,
 	.atomic_destroy_state = intel_crtc_destroy_state,
 };
-- 
2.8.1