From e1fdc473bb065888fec4535103d25483addd666f Mon Sep 17 00:00:00 2001 From: Paulo Zanoni Date: Fri, 17 Jan 2014 13:51:12 -0200 Subject: [PATCH] drm/i915: remove wait_for_vblank argument form intel_enable_pipe Add a nice comment explaining why we shouldn't wait for a vblank on all cases, wait based on the HW gen, and add a comment saying we should probably skip that wait on some of the previous HW gens. Signed-off-by: Paulo Zanoni Reviewed-by: Damien Lespiau Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/intel_display.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 71b056534728..b040bd43bfd7 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -1747,12 +1747,11 @@ static void lpt_disable_pch_transcoder(struct drm_i915_private *dev_priv) /** * intel_enable_pipe - enable a pipe, asserting requirements * @crtc: crtc responsible for the pipe - * @wait_for_vblank: whether we should for a vblank or not after enabling it * * Enable @crtc's pipe, making sure that various hardware specific requirements * are met, if applicable, e.g. PLL enabled, LVDS pairs enabled, etc. */ -static void intel_enable_pipe(struct intel_crtc *crtc, bool wait_for_vblank) +static void intel_enable_pipe(struct intel_crtc *crtc) { struct drm_device *dev = crtc->base.dev; struct drm_i915_private *dev_priv = dev->dev_private; @@ -1799,7 +1798,15 @@ static void intel_enable_pipe(struct intel_crtc *crtc, bool wait_for_vblank) I915_WRITE(reg, val | PIPECONF_ENABLE); POSTING_READ(reg); - if (wait_for_vblank) + + /* + * There's no guarantee the pipe will really start running now. It + * depends on the Gen, the output type and the relative order between + * pipe and plane enabling. Avoid waiting on HSW+ since it's not + * necessary. + * TODO: audit the previous gens. + */ + if (INTEL_INFO(dev)->gen <= 7 && !IS_HASWELL(dev)) intel_wait_for_vblank(dev_priv->dev, pipe); } @@ -3596,7 +3603,7 @@ static void ironlake_crtc_enable(struct drm_crtc *crtc) intel_crtc_load_lut(crtc); intel_update_watermarks(crtc); - intel_enable_pipe(intel_crtc, true); + intel_enable_pipe(intel_crtc); intel_enable_primary_plane(dev_priv, plane, pipe); intel_enable_planes(crtc); intel_crtc_update_cursor(crtc, true); @@ -3741,7 +3748,7 @@ static void haswell_crtc_enable(struct drm_crtc *crtc) intel_ddi_enable_transcoder_func(crtc); intel_update_watermarks(crtc); - intel_enable_pipe(intel_crtc, false); + intel_enable_pipe(intel_crtc); if (intel_crtc->config.has_pch_encoder) lpt_pch_enable(crtc); @@ -4166,7 +4173,7 @@ static void valleyview_crtc_enable(struct drm_crtc *crtc) intel_crtc_load_lut(crtc); intel_update_watermarks(crtc); - intel_enable_pipe(intel_crtc, true); + intel_enable_pipe(intel_crtc); intel_set_cpu_fifo_underrun_reporting(dev, pipe, true); intel_enable_primary_plane(dev_priv, plane, pipe); intel_enable_planes(crtc); @@ -4205,7 +4212,7 @@ static void i9xx_crtc_enable(struct drm_crtc *crtc) intel_crtc_load_lut(crtc); intel_update_watermarks(crtc); - intel_enable_pipe(intel_crtc, true); + intel_enable_pipe(intel_crtc); intel_set_cpu_fifo_underrun_reporting(dev, pipe, true); intel_enable_primary_plane(dev_priv, plane, pipe); intel_enable_planes(crtc); -- 2.20.1