From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> We get spurious PCH FIFO underruns if we enable the reporting too soon after enabling the crtc. Move it to be the last step, after the encoder enable. Additionally we need an extra vblank wait, otherwise we still get the underruns. Presumably the pipe/fdi isn't yet fully up and running otherwise. For symmetry, disable the PCH underrun reporting as the first thing, just before encoder disable, when shutting down the crtc. v2: Do the PCH underrun enable unconditionally (Jani, Daniel) Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> Reviewed-by: Jesse Barnes <jbarnes@xxxxxxxxxxxxxxxx> (v1) --- drivers/gpu/drm/i915/intel_display.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index e4f5b1f..5ab39af 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -4874,7 +4874,6 @@ static void ironlake_crtc_enable(struct drm_crtc *crtc) intel_crtc->active = true; intel_set_cpu_fifo_underrun_reporting(dev_priv, pipe, true); - intel_set_pch_fifo_underrun_reporting(dev_priv, pipe, true); for_each_encoder_on_crtc(dev, crtc, encoder) if (encoder->pre_enable) @@ -4912,6 +4911,11 @@ static void ironlake_crtc_enable(struct drm_crtc *crtc) if (HAS_PCH_CPT(dev)) cpt_verify_modeset(dev, intel_crtc->pipe); + + /* Must wait for vblank to avoid spurious PCH FIFO underruns */ + if (intel_crtc->config->has_pch_encoder) + intel_wait_for_vblank(dev, pipe); + intel_set_pch_fifo_underrun_reporting(dev_priv, pipe, true); } /* IPS only exists on ULT machines and is tied to pipe A. */ @@ -5040,15 +5044,15 @@ static void ironlake_crtc_disable(struct drm_crtc *crtc) int pipe = intel_crtc->pipe; u32 reg, temp; + if (intel_crtc->config->has_pch_encoder) + intel_set_pch_fifo_underrun_reporting(dev_priv, pipe, false); + for_each_encoder_on_crtc(dev, crtc, encoder) encoder->disable(encoder); drm_crtc_vblank_off(crtc); assert_vblank_disabled(crtc); - if (intel_crtc->config->has_pch_encoder) - intel_set_pch_fifo_underrun_reporting(dev_priv, pipe, false); - intel_disable_pipe(intel_crtc); ironlake_pfit_disable(intel_crtc, false); -- 2.4.10 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx