Merge tag 'imx-drm-fixes-2016-11-10' of git://git.pengutronix.de/git/pza/linux into drm-fixes
imx-drm: fix possible hangup when disabling crtcs
- only ever disable the display controller (DC) module after all plane
IDMAC channels are stopped. This fixes a regression introduced by the
atomic modeset conversion.
* tag 'imx-drm-fixes-2016-11-10' of git://git.pengutronix.de/git/pza/linux:
drm/imx: disable planes before DC
diff --git a/drivers/gpu/drm/imx/ipuv3-crtc.c b/drivers/gpu/drm/imx/ipuv3-crtc.c
index 4e1ae3f..6be515a 100644
--- a/drivers/gpu/drm/imx/ipuv3-crtc.c
+++ b/drivers/gpu/drm/imx/ipuv3-crtc.c
@@ -68,6 +68,12 @@
ipu_dc_disable_channel(ipu_crtc->dc);
ipu_di_disable(ipu_crtc->di);
+ /*
+ * Planes must be disabled before DC clock is removed, as otherwise the
+ * attached IDMACs will be left in undefined state, possibly hanging
+ * the IPU or even system.
+ */
+ drm_atomic_helper_disable_planes_on_crtc(old_crtc_state, false);
ipu_dc_disable(ipu);
spin_lock_irq(&crtc->dev->event_lock);
@@ -77,9 +83,6 @@
}
spin_unlock_irq(&crtc->dev->event_lock);
- /* always disable planes on the CRTC */
- drm_atomic_helper_disable_planes_on_crtc(old_crtc_state, true);
-
drm_crtc_vblank_off(crtc);
}