From c4bd9665b145cacfdf9cbd5f3d83ed0961080236 Mon Sep 17 00:00:00 2001 From: Mario Kleiner Date: Tue, 19 Jul 2016 20:59:01 +0200 Subject: [PATCH] drm/vc4: Enable/Disable vblanks properly in crtc en/disable. Add missing drm_crtc_vblank_on/off() calls so vblank irq handling/updating/timestamping never runs with a crtc shut down or during its shutdown/startup, as that causes large jumps in vblank count and trouble for compositors. Signed-off-by: Mario Kleiner Signed-off-by: Eric Anholt --- drivers/gpu/drm/vc4/vc4_crtc.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/drivers/gpu/drm/vc4/vc4_crtc.c +++ b/drivers/gpu/drm/vc4/vc4_crtc.c @@ -468,6 +468,9 @@ static void vc4_crtc_disable(struct drm_ int ret; require_hvs_enabled(dev); + /* Disable vblank irq handling before crtc is disabled. */ + drm_crtc_vblank_off(crtc); + if (VC4_DSI_USE_FIRMWARE_SETUP && (CRTC_READ(PV_V_CONTROL) & PV_VCONTROL_DSI)) { /* Skip disabling the PV/HVS for the channel if it was @@ -531,6 +534,9 @@ static void vc4_crtc_enable(struct drm_c /* Turn on the pixel valve, which will emit the vstart signal. */ CRTC_WRITE(PV_V_CONTROL, CRTC_READ(PV_V_CONTROL) | PV_VCONTROL_VIDEN); + + /* Enable vblank irq handling after crtc is started. */ + drm_crtc_vblank_on(crtc); } static bool vc4_crtc_mode_fixup(struct drm_crtc *crtc,