[Intel-gfx] [RFC] drm/i915: don't wait_for_vblank if the CRTC is disabled

[Paulo Zanoni]

From: Paulo Zanoni <paulo.r.zanoni at intel.com>

Otherwise we'll get a WARN from drm_wait_one_vblank() saying that
vblanks are not available (since they were already disabled in
crtc_disable()).

This is certainly a regresison, but QA couldn't bisect it due to
other regressions breaking the bisect.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=89550
Testcase: igt/pm_rpm/legacy-planes
Testcase: igt/pm_rpm/legacy-planes-dpms
Testcase: igt/pm_rpm/universal-planes
Testcase: igt/pm_rpm/universal-planes-dpms
Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
Cc: Matt Roper <matthew.d.roper at intel.com>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni at intel.com>
---
 drivers/gpu/drm/i915/intel_display.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)


I'm not really sure if this is the best way to fix the regression. Ville and/or
Matt should provide some comments here.


diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index f1c0295..f2f7e81 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -12193,7 +12193,7 @@ static void intel_finish_crtc_commit(struct drm_crtc *crtc)
 
 	intel_runtime_pm_put(dev_priv);
 
-	if (intel_crtc->atomic.wait_vblank)
+	if (intel_crtc->active && intel_crtc->atomic.wait_vblank)
 		intel_wait_for_vblank(dev, intel_crtc->pipe);
 
 	intel_frontbuffer_flip(dev, intel_crtc->atomic.fb_bits);
-- 
2.1.4