Similar to commit 37ca8d4ccd9860df0747aa2ea281a3c9c4bf8826 Author: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> Date: Fri Oct 30 19:20:27 2015 +0200 drm/i915: Enable PCH FIFO underruns later on ILK/SNB/IVB we can only enable fifo underrun reporting when using the fdi/lpt after everything is set up and after a bit of waiting. The waiting is required, enabling it right after enabling encoders will first trigger an underrun on the pch and then, 1 frame later, an underrun on the cpu. Two vblank waits after encoder enabling seems enough to curb it. And similar to Author: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> Date: Fri Nov 20 22:09:18 2015 +0200 drm/i915: Suppress spurious CPU FIFO underruns on ILK-IVB we also need to make sure cpu fifo underrun reporting is disabled when enabling the fdi rx/tx and pch transcoder&port. But somehow this is only needed when enabling, not also when disabling. Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxx> --- drivers/gpu/drm/i915/intel_display.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 7754db9fa8a4..62097e94996a 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -4979,7 +4979,11 @@ static void haswell_crtc_enable(struct drm_crtc *crtc) intel_crtc->active = true; - intel_set_cpu_fifo_underrun_reporting(dev_priv, pipe, true); + if (intel_crtc->config->has_pch_encoder) + intel_set_cpu_fifo_underrun_reporting(dev_priv, pipe, false); + else + intel_set_cpu_fifo_underrun_reporting(dev_priv, pipe, true); + for_each_encoder_on_crtc(dev, crtc, encoder) { if (encoder->pre_pll_enable) encoder->pre_pll_enable(encoder); @@ -5025,9 +5029,13 @@ static void haswell_crtc_enable(struct drm_crtc *crtc) intel_opregion_notify_encoder(encoder, true); } - if (intel_crtc->config->has_pch_encoder) + if (intel_crtc->config->has_pch_encoder) { + intel_wait_for_vblank(dev, pipe); + intel_wait_for_vblank(dev, pipe); + intel_set_cpu_fifo_underrun_reporting(dev_priv, pipe, true); intel_set_pch_fifo_underrun_reporting(dev_priv, TRANSCODER_A, true); + } /* If we change the relative order between pipe/planes enabling, we need * to change the workaround. */ -- 2.1.0 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx