From: Daniel Vetter <daniel.vetter@xxxxxxxx> commit 0ca09685546fed5fc8f0535204f0626f352140f4 upstream. Nothing in Bspec seems to indicate that we actually needs this, and it looks like can't work since by this point the pipe is off and so vblanks won't really happen any more. Note that Bspec mentions that it takes a vblank for this bit to change, but _only_ when enabling. Dropping this code quenches an annoying backtrace introduced by the more anal checking since commit 51e31d49c89055299e34b8f44d13f70e19aaaad1 Author: Daniel Vetter <daniel.vetter@xxxxxxxx> Date: Mon Sep 15 12:36:02 2014 +0200 drm/i915: Use generic vblank wait Note: This fixes the fallout from the above commit, but does not address the shortcomings of the IBX transcoder select workaround implementation discussed during review [1]. [1] http://mid.gmane.org/87y4o7usxf.fsf@xxxxxxxxx Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=86095 Signed-off-by: Daniel Vetter <daniel.vetter@xxxxxxxxx> Reviewed-by: Paulo Zanoni <paulo.r.zanoni@xxxxxxxxx> Signed-off-by: Jani Nikula <jani.nikula@xxxxxxxxx> Signed-off-by: Sasha Levin <sasha.levin@xxxxxxxxxx> --- drivers/gpu/drm/i915/intel_dp.c | 17 +---------------- 1 file changed, 1 insertion(+), 16 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 4bcd917..740d9eb 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -3645,8 +3645,6 @@ intel_dp_link_down(struct intel_dp *intel_dp) enum port port = intel_dig_port->port; struct drm_device *dev = intel_dig_port->base.base.dev; struct drm_i915_private *dev_priv = dev->dev_private; - struct intel_crtc *intel_crtc = - to_intel_crtc(intel_dig_port->base.base.crtc); uint32_t DP = intel_dp->DP; if (WARN_ON(HAS_DDI(dev))) @@ -3671,8 +3669,6 @@ intel_dp_link_down(struct intel_dp *intel_dp) if (HAS_PCH_IBX(dev) && I915_READ(intel_dp->output_reg) & DP_PIPEB_SELECT) { - struct drm_crtc *crtc = intel_dig_port->base.base.crtc; - /* Hardware workaround: leaving our transcoder select * set to transcoder B while it's off will prevent the * corresponding HDMI output on transcoder A. @@ -3683,18 +3679,7 @@ intel_dp_link_down(struct intel_dp *intel_dp) */ DP &= ~DP_PIPEB_SELECT; I915_WRITE(intel_dp->output_reg, DP); - - /* Changes to enable or select take place the vblank - * after being written. - */ - if (WARN_ON(crtc == NULL)) { - /* We should never try to disable a port without a crtc - * attached. For paranoia keep the code around for a - * bit. */ - POSTING_READ(intel_dp->output_reg); - msleep(50); - } else - intel_wait_for_vblank(dev, intel_crtc->pipe); + POSTING_READ(intel_dp->output_reg); } DP &= ~DP_AUDIO_OUTPUT_ENABLE; -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html