[Intel-gfx] [PATCH] drm/i915: Try to fix MST for SKL

Bish, Jim jim.bish at intel.com
Mon Nov 23 15:38:32 PST 2015


On Thu, 2015-11-19 at 22:28 +0100, Kenneth Johansson wrote:
> On 2015-11-10 21:15, Jesse Barnes wrote:
> > On 08/17/2015 08:46 AM, ville.syrjala at linux.intel.com wrote:
> > > From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > > 
> > > Set up the DDI->PLL mapping on SKL also for MST links. Might help
> > > make
> > > MST operational on SKL.
> > > 
> > > Cc: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
> > > Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > > ---
> > >   drivers/gpu/drm/i915/intel_ddi.c    | 49 ++++++++++++++++++++++
> > > ---------------
> > >   drivers/gpu/drm/i915/intel_dp_mst.c |  8 +-----
> > >   drivers/gpu/drm/i915/intel_drv.h    |  2 ++
> > >   3 files changed, 32 insertions(+), 27 deletions(-)
> > > 
> > > diff --git a/drivers/gpu/drm/i915/intel_ddi.c
> > > b/drivers/gpu/drm/i915/intel_ddi.c
> > > index 5dff8b7..10a5a98 100644
> > > --- a/drivers/gpu/drm/i915/intel_ddi.c
> > > +++ b/drivers/gpu/drm/i915/intel_ddi.c
> > > @@ -2258,30 +2258,21 @@ uint32_t ddi_signal_levels(struct
> > > intel_dp *intel_dp)
> > >   	return DDI_BUF_TRANS_SELECT(level);
> > >   }
> > >   
> > > -static void intel_ddi_pre_enable(struct intel_encoder
> > > *intel_encoder)
> > > +void intel_ddi_clk_select(struct intel_encoder *encoder,
> > > +			  const struct intel_crtc_state
> > > *pipe_config)
> > >   {
> > > -	struct drm_encoder *encoder = &intel_encoder->base;
> > > -	struct drm_device *dev = encoder->dev;
> > > -	struct drm_i915_private *dev_priv = dev->dev_private;
> > > -	struct intel_crtc *crtc = to_intel_crtc(encoder->crtc);
> > > -	enum port port =
> > > intel_ddi_get_encoder_port(intel_encoder);
> > > -	int type = intel_encoder->type;
> > > -	int hdmi_level;
> > > -
> > > -	if (type == INTEL_OUTPUT_EDP) {
> > > -		struct intel_dp *intel_dp =
> > > enc_to_intel_dp(encoder);
> > > -		intel_edp_panel_on(intel_dp);
> > > -	}
> > > +	struct drm_i915_private *dev_priv = to_i915(encoder
> > > ->base.dev);
> > > +	enum port port = intel_ddi_get_encoder_port(encoder);
> > >   
> > > -	if (IS_SKYLAKE(dev)) {
> > > -		uint32_t dpll = crtc->config->ddi_pll_sel;
> > > +	if (IS_SKYLAKE(dev_priv)) {
> > > +		uint32_t dpll = pipe_config->ddi_pll_sel;
> > >   		uint32_t val;
> > >   
> > >   		/*
> > >   		 * DPLL0 is used for eDP and is the only
> > > "private" DPLL (as
> > >   		 * opposed to shared) on SKL
> > >   		 */
> > > -		if (type == INTEL_OUTPUT_EDP) {
> > > +		if (encoder->type == INTEL_OUTPUT_EDP) {
> > >   			WARN_ON(dpll != SKL_DPLL0);
> > >   
> > >   			val = I915_READ(DPLL_CTRL1);
> > > @@ -2289,7 +2280,7 @@ static void intel_ddi_pre_enable(struct
> > > intel_encoder *intel_encoder)
> > >   			val &= ~(DPLL_CTRL1_HDMI_MODE(dpll) |
> > >   				 DPLL_CTRL1_SSC(dpll) |
> > >   				 DPLL_CTRL1_LINK_RATE_MASK(dpll
> > > ));
> > > -			val |= crtc->config->dpll_hw_state.ctrl1
> > > << (dpll * 6);
> > > +			val |= pipe_config->dpll_hw_state.ctrl1
> > > << (dpll * 6);
> > >   
> > >   			I915_WRITE(DPLL_CTRL1, val);
> > >   			POSTING_READ(DPLL_CTRL1);
> > > @@ -2305,11 +2296,29 @@ static void intel_ddi_pre_enable(struct
> > > intel_encoder *intel_encoder)
> > >   
> > >   		I915_WRITE(DPLL_CTRL2, val);
> > >   
> > > -	} else if (INTEL_INFO(dev)->gen < 9) {
> > > -		WARN_ON(crtc->config->ddi_pll_sel ==
> > > PORT_CLK_SEL_NONE);
> > > -		I915_WRITE(PORT_CLK_SEL(port), crtc->config
> > > ->ddi_pll_sel);
> > > +	} else if (INTEL_INFO(dev_priv)->gen < 9) {
> > > +		WARN_ON(pipe_config->ddi_pll_sel ==
> > > PORT_CLK_SEL_NONE);
> > > +		I915_WRITE(PORT_CLK_SEL(port), pipe_config
> > > ->ddi_pll_sel);
> > > +	}
> > > +}
> > > +
> > > +static void intel_ddi_pre_enable(struct intel_encoder
> > > *intel_encoder)
> > > +{
> > > +	struct drm_encoder *encoder = &intel_encoder->base;
> > > +	struct drm_device *dev = encoder->dev;
> > > +	struct drm_i915_private *dev_priv = dev->dev_private;
> > > +	struct intel_crtc *crtc = to_intel_crtc(encoder->crtc);
> > > +	enum port port =
> > > intel_ddi_get_encoder_port(intel_encoder);
> > > +	int type = intel_encoder->type;
> > > +	int hdmi_level;
> > > +
> > > +	if (type == INTEL_OUTPUT_EDP) {
> > > +		struct intel_dp *intel_dp =
> > > enc_to_intel_dp(encoder);
> > > +		intel_edp_panel_on(intel_dp);
> > >   	}
> > >   
> > > +	intel_ddi_clk_select(intel_encoder, crtc->config);
> > > +
> > >   	if (type == INTEL_OUTPUT_DISPLAYPORT || type ==
> > > INTEL_OUTPUT_EDP) {
> > >   		struct intel_dp *intel_dp =
> > > enc_to_intel_dp(encoder);
> > >   
> > > diff --git a/drivers/gpu/drm/i915/intel_dp_mst.c
> > > b/drivers/gpu/drm/i915/intel_dp_mst.c
> > > index ebf2054..fd25aeb7 100644
> > > --- a/drivers/gpu/drm/i915/intel_dp_mst.c
> > > +++ b/drivers/gpu/drm/i915/intel_dp_mst.c
> > > @@ -163,20 +163,14 @@ static void intel_mst_pre_enable_dp(struct
> > > intel_encoder *encoder)
> > >   	intel_mst->port = found->port;
> > >   
> > >   	if (intel_dp->active_mst_links == 0) {
> > > -		enum port port =
> > > intel_ddi_get_encoder_port(encoder);
> > > +		intel_ddi_clk_select(encoder, intel_crtc
> > > ->config);
> > >   
> > >   		intel_dp_set_link_params(intel_dp, intel_crtc
> > > ->config);
> > >   
> > > -		/* FIXME: add support for SKL */
> > > -		if (INTEL_INFO(dev)->gen < 9)
> > > -			I915_WRITE(PORT_CLK_SEL(port),
> > > -				   intel_crtc->config
> > > ->ddi_pll_sel);
> > > -
> > >   		intel_ddi_init_dp_buf_reg(&intel_dig_port
> > > ->base);
> > >   
> > >   		intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_ON);
> > >   
> > > -
> > >   		intel_dp_start_link_train(intel_dp);
> > >   		intel_dp_complete_link_train(intel_dp);
> > >   		intel_dp_stop_link_train(intel_dp);
> > > diff --git a/drivers/gpu/drm/i915/intel_drv.h
> > > b/drivers/gpu/drm/i915/intel_drv.h
> > > index 71a2e18..a97908a 100644
> > > --- a/drivers/gpu/drm/i915/intel_drv.h
> > > +++ b/drivers/gpu/drm/i915/intel_drv.h
> > > @@ -938,6 +938,8 @@ void intel_crt_init(struct drm_device *dev);
> > >   
> > >   
> > >   /* intel_ddi.c */
> > > +void intel_ddi_clk_select(struct intel_encoder *encoder,
> > > +			  const struct intel_crtc_state
> > > *pipe_config);
> > >   void intel_prepare_ddi(struct drm_device *dev);
> > >   void hsw_fdi_link_train(struct drm_crtc *crtc);
> > >   void intel_ddi_init(struct drm_device *dev, enum port port);
> > > 
> > Looks like an improvement over current code and fixes the hard hang
> > in
> > https://bugs.freedesktop.org/show_bug.cgi?id=91791, so I think we
> > should
> > push it.
> > 
> > Sounds like we need more than just this to fix MST on SKL though.
> 
> I tested against dell 4k UP3214Q  and I still have a hard hang so yes
> MST on skylake is not in a good shape.
Just tested on special kernel for yoga 900 with USB Type C to DP
adapter connected to Club 3D MST Hub (CSV-5200).  Mostly works with
2560x1440 on local display and dual head Samsung 4k monitors - same
resolution on all.  I am writing this e-mail on one of the samsung
monitors.  have pictures if you are interested.

Also, I am getting watermark stack traces and periodic drops of the MST
displays - blank then re-appear.

Jim
> > 
> > Reviewed-by: Jesse Barnes <jbarnes at virtuousgeek.org>
> > _______________________________________________
> > Intel-gfx mailing list
> > Intel-gfx at lists.freedesktop.org
> > http://lists.freedesktop.org/mailman/listinfo/intel-gfx
> 
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx


More information about the Intel-gfx mailing list