Commit a5b534bb authored by Dave Stevenson's avatar Dave Stevenson Committed by Phil Elwell
Browse files

drm/vc4: Resolve the vblank warnings on mode switching 

The details over when and how a driver is to service the
vblank events are sketchy, and the fkms driver was triggering
a kernel warning every time the crtc was enabled or disabled.

Copy the event handling as used by the vc4-kms driver slightly
more closely, and we avoid the warnings.

https://github.com/raspberrypi/linux/issues/3020



Signed-off-by: default avatarDave Stevenson <dave.stevenson@raspberrypi.org>
parent ea858388

drivers/gpu/drm/vc4/vc4_firmware_kms.c

+33 −15
Original line number Diff line number Diff line
@@ -933,6 +933,7 @@ static void vc4_crtc_mode_set_nofb(struct drm_crtc *crtc) 


static void vc4_crtc_disable(struct drm_crtc *crtc, struct drm_crtc_state *old_state)

{

	struct drm_device *dev = crtc->dev;

	struct drm_plane *plane;



	DRM_DEBUG_KMS("[CRTC:%d] vblanks off.\n",
@@ -948,6 +949,35 @@ static void vc4_crtc_disable(struct drm_crtc *crtc, struct drm_crtc_state *old_s 


	drm_atomic_crtc_for_each_plane(plane, crtc)

		vc4_plane_atomic_disable(plane, plane->state);



	/*

	 * Make sure we issue a vblank event after disabling the CRTC if

	 * someone was waiting it.

	 */

	if (crtc->state->event) {

		unsigned long flags;



		spin_lock_irqsave(&dev->event_lock, flags);

		drm_crtc_send_vblank_event(crtc, crtc->state->event);

		crtc->state->event = NULL;

		spin_unlock_irqrestore(&dev->event_lock, flags);

	}

}



static void vc4_crtc_consume_event(struct drm_crtc *crtc)

{

	struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);

	struct drm_device *dev = crtc->dev;

	unsigned long flags;



	crtc->state->event->pipe = drm_crtc_index(crtc);



	WARN_ON(drm_crtc_vblank_get(crtc) != 0);



	spin_lock_irqsave(&dev->event_lock, flags);

	vc4_crtc->event = crtc->state->event;

	crtc->state->event = NULL;

	spin_unlock_irqrestore(&dev->event_lock, flags);

}



static void vc4_crtc_enable(struct drm_crtc *crtc, struct drm_crtc_state *old_state)
@@ -957,6 +987,7 @@ static void vc4_crtc_enable(struct drm_crtc *crtc, struct drm_crtc_state *old_st 
	DRM_DEBUG_KMS("[CRTC:%d] vblanks on.\n",

		      crtc->base.id);

	drm_crtc_vblank_on(crtc);

	vc4_crtc_consume_event(crtc);



	/* Unblank the planes (if they're supposed to be displayed). */

	drm_atomic_crtc_for_each_plane(plane, crtc)
@@ -1028,23 +1059,10 @@ static int vc4_crtc_atomic_check(struct drm_crtc *crtc, 
static void vc4_crtc_atomic_flush(struct drm_crtc *crtc,

				  struct drm_crtc_state *old_state)

{

	struct vc4_crtc *vc4_crtc = to_vc4_crtc(crtc);

	struct drm_device *dev = crtc->dev;



	DRM_DEBUG_KMS("[CRTC:%d] crtc_atomic_flush.\n",

		      crtc->base.id);

	if (crtc->state->event) {

		unsigned long flags;



		crtc->state->event->pipe = drm_crtc_index(crtc);



		WARN_ON(drm_crtc_vblank_get(crtc) != 0);



		spin_lock_irqsave(&dev->event_lock, flags);

		vc4_crtc->event = crtc->state->event;

		crtc->state->event = NULL;

		spin_unlock_irqrestore(&dev->event_lock, flags);

	}

	if (crtc->state->active && old_state->active && crtc->state->event)

		vc4_crtc_consume_event(crtc);

}



static void vc4_crtc_handle_page_flip(struct vc4_crtc *vc4_crtc)