From 9625604cebcb3f5be2e692408274734e8ae63979 Mon Sep 17 00:00:00 2001 From: Daniel Vetter Date: Fri, 13 Feb 2015 21:03:42 +0100 Subject: drm/irq: Add drm_crtc_vblank_reset MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit At driver load we need to tell the vblank code about the state of the pipes, so that the logic around reject vblank_get when the pipe is off works correctly. Thus far i915 used drm_vblank_off, but one of the side-effects of it is that it also saves the vblank counter. And for that it calls down into the ->get_vblank_counter hook. Which isn't really a good idea when the pipe is off for a few reasons: - With runtime pm the register might not respond. - If the pipe is off some datastructures might not be around or unitialized. The later is what blew up on gen3: We look at intel_crtc->config to compute the vblank counter, and for a disabled pipe at boot-up that's just not there. Thus far this was papered over by a check for intel_crtc->active, but I want to get rid of that (since it's fairly race, vblank hooks are called from all kinds of places). So prep for that by adding a _reset functions which only does what we really need to be done at driver load: Mark the vblank pipe as off, but don't do any vblank counter saving or event flushing - neither of that is required. v2: Clarify the code flow slightly as suggested by Ville. v3: Fix kerneldoc spelling, spotted by Laurent. Cc: Ville Syrjälä Cc: Laurent Pinchart Cc: Imre Deak Reviewed-by: Imre Deak (v2) Acked-by: Dave Airlie Acked-by: Laurent Pinchart Signed-off-by: Daniel Vetter --- include/drm/drmP.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/drm') diff --git a/include/drm/drmP.h b/include/drm/drmP.h index e928625a9da0..54c6ea1e5866 100644 --- a/include/drm/drmP.h +++ b/include/drm/drmP.h @@ -922,6 +922,7 @@ extern void drm_crtc_wait_one_vblank(struct drm_crtc *crtc); extern void drm_vblank_off(struct drm_device *dev, int crtc); extern void drm_vblank_on(struct drm_device *dev, int crtc); extern void drm_crtc_vblank_off(struct drm_crtc *crtc); +extern void drm_crtc_vblank_reset(struct drm_crtc *crtc); extern void drm_crtc_vblank_on(struct drm_crtc *crtc); extern void drm_vblank_cleanup(struct drm_device *dev); -- cgit v1.2.3-59-g8ed1b