Hi Daniel,
On Wednesday 08 Jun 2016 14:18:58 Daniel Vetter wrote:
atomic_flush seems to be the right place, right after we commit the plane updates. Again use the fullproof version, since the pipe might be off.
Cc: Boris Brezillon boris.brezillon@free-electrons.com Cc: Maxime Ripard maxime.ripard@free-electrons.com Signed-off-by: Daniel Vetter daniel.vetter@intel.com
drivers/gpu/drm/sun4i/sun4i_crtc.c | 12 ++++++++++++ 1 file changed, 12 insertions(+)
diff --git a/drivers/gpu/drm/sun4i/sun4i_crtc.c b/drivers/gpu/drm/sun4i/sun4i_crtc.c index 4182a21f5923..f628b6d8f23f 100644 --- a/drivers/gpu/drm/sun4i/sun4i_crtc.c +++ b/drivers/gpu/drm/sun4i/sun4i_crtc.c @@ -51,10 +51,22 @@ static void sun4i_crtc_atomic_flush(struct drm_crtc *crtc, { struct sun4i_crtc *scrtc = drm_crtc_to_sun4i_crtc(crtc); struct sun4i_drv *drv = scrtc->drv;
struct drm_pending_vblank_event *event = crtc->state->event;
DRM_DEBUG_DRIVER("Committing plane changes\n");
sun4i_backend_commit(drv->backend);
if (event) {
crtc->state->event = NULL;spin_lock_irq(&crtc->dev->event_lock);if (drm_crtc_vblank_get(crtc) == 0)drm_crtc_arm_vblank_event(crtc, event);elsedrm_crtc_send_vblank_event(crtc, event);spin_unlock_irq(&crtc->dev->event_lock);}
Is it me, or is it entirely useless given the code in sun4i_crtc_atomic_flush() that sets crtc->state->event to NULL ?
AuthorDate: Wed Jun 8 14:18:58 2016 +0200 CommitDate: Fri Jun 10 16:55:48 2016 +0200
It would have been worth it waiting for the maintainers to review the patch...
You've added similar code to a bunch of drivers. How do you protect against the race conditions documented in the drm_crtc_arm_vblank_event() function ?
}
static void sun4i_crtc_disable(struct drm_crtc *crtc)