From 6b6985169017e554d80a8c2befdadbd81d13c2a2 Mon Sep 17 00:00:00 2001 From: Daniel Vetter Date: Sat, 28 Nov 2015 11:05:39 +0100 Subject: [PATCH] drm/i915: fix fdi related fifo underruns on hsw MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Similar to commit 37ca8d4ccd9860df0747aa2ea281a3c9c4bf8826 Author: Ville Syrjälä 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 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 Link: http://patchwork.freedesktop.org/patch/msgid/1448705139-12534-1-git-send-email-daniel.vetter@ffwll.ch Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=91578 Tested-by: Mika Kahola Reviewed-by: Mika Kahola Signed-off-by: Daniel Vetter --- 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 b95c325..b332326 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -4978,7 +4978,11 @@ 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_enable) encoder->pre_enable(encoder); @@ -5022,9 +5026,13 @@ 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. */ -- 2.7.4