[Intel-gfx] [PATCH v3] drm/i915/mst: Use MST sideband message transactions for dpms control

[Lyude Paul]

On Wed, 2017-10-04 at 11:47 +0300, Jani Nikula wrote:
> On Tue, 03 Oct 2017, Jani Nikula <jani.nikula at intel.com> wrote:
> > From: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>
> > 
> > Use the POWER_DOWN_PHY and POWER_UP_PHY sideband message transactions to
> > set power states for downstream sinks. Apart from giving us the ability
> > to set power state for individual sinks, this fixes the below test for
> > me.
> > 
> > $ xrandr --display :0 --output DP-2-2-8 --off
> > $ xrandr --display :0 --output DP-2-2-1 --off
> > $ xrandr --display :0 --output DP-2-2-8 --auto #Black screen
> > $ xrandr --display :0 --output DP-2-2-1 --auto
> > 
> > v2: Modify and document the dpms and port disable order (Ville)
> >     Add comment explaining is_mst = !crtc_state equivalence(Ville,
> > Maarten)
> > 
> > v3 by Jani: rebase
> > 
> > References: https://bugs.freedesktop.org/show_bug.cgi?id=90963
> > References: https://bugs.freedesktop.org/show_bug.cgi?id=88124
> > Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > Cc: Lyude <lyude at redhat.com>
> > Cc: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
> > Reviewed-by: Lyude Paul <lyude at redhat.com>
> > Acked-by: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
> 
> Lyude, Maarten, can you confirm your rb/ack on my rebase please?
Looks good to me
> 
> BR,
> Jani.
> 
> 
> > Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>
> > Signed-off-by: Jani Nikula <jani.nikula at intel.com>
> > ---
> >  drivers/gpu/drm/i915/intel_ddi.c    | 18 ++++++++++++++----
> >  drivers/gpu/drm/i915/intel_dp_mst.c | 10 ++++++++--
> >  2 files changed, 22 insertions(+), 6 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/intel_ddi.c
> > b/drivers/gpu/drm/i915/intel_ddi.c
> > index 65f4b6786791..511aa60e0176 100644
> > --- a/drivers/gpu/drm/i915/intel_ddi.c
> > +++ b/drivers/gpu/drm/i915/intel_ddi.c
> > @@ -2162,7 +2162,8 @@ static void intel_ddi_pre_enable_dp(struct
> > intel_encoder *encoder,
> >  		intel_prepare_dp_ddi_buffers(encoder);
> >  
> >  	intel_ddi_init_dp_buf_reg(encoder);
> > -	intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_ON);
> > +	if (!link_mst)
> > +		intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_ON);
> >  	intel_dp_start_link_train(intel_dp);
> >  	if (port != PORT_A || INTEL_GEN(dev_priv) >= 9)
> >  		intel_dp_stop_link_train(intel_dp);
> > @@ -2236,12 +2237,21 @@ static void intel_ddi_post_disable(struct
> > intel_encoder *intel_encoder,
> >  	uint32_t val;
> >  	bool wait = false;
> >  
> > -	/* old_crtc_state and old_conn_state are NULL when called from
> > DP_MST */
> > -
> >  	if (type == INTEL_OUTPUT_DP || type == INTEL_OUTPUT_EDP) {
> > +		/*
> > +		 * old_crtc_state and old_conn_state are NULL when called
> > from
> > +		 * DP_MST. The main connector associated with this port
> > is never
> > +		 * bound to a crtc for MST.
> > +		 */
> > +		bool is_mst = !old_crtc_state;
> >  		struct intel_dp *intel_dp = enc_to_intel_dp(encoder);
> >  
> > -		intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_OFF);
> > +		/*
> > +		 * Power down sink before disabling the port, otherwise
> > we end
> > +		 * up getting interrupts from the sink on detecting link
> > loss.
> > +		 */
> > +		if (!is_mst)
> > +			intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_OFF);
> >  	}
> >  
> >  	val = I915_READ(DDI_BUF_CTL(port));
> > diff --git a/drivers/gpu/drm/i915/intel_dp_mst.c
> > b/drivers/gpu/drm/i915/intel_dp_mst.c
> > index 9a396f483f8b..3c131e2544cf 100644
> > --- a/drivers/gpu/drm/i915/intel_dp_mst.c
> > +++ b/drivers/gpu/drm/i915/intel_dp_mst.c
> > @@ -162,14 +162,19 @@ static void intel_mst_post_disable_dp(struct
> > intel_encoder *encoder,
> >  
> >  	drm_dp_mst_deallocate_vcpi(&intel_dp->mst_mgr, connector->port);
> >  
> > +	/*
> > +	 * Power down mst path before disabling the port, otherwise we
> > end
> > +	 * up getting interrupts from the sink upon detecting link loss.
> > +	 */
> > +	drm_dp_send_power_updown_phy(&intel_dp->mst_mgr, connector->port,
> > +				     false);
> > +
> >  	intel_dp->active_mst_links--;
> >  
> >  	intel_mst->connector = NULL;
> >  	if (intel_dp->active_mst_links == 0) {
> >  		intel_dig_port->base.post_disable(&intel_dig_port->base,
> >  						  NULL, NULL);
> > -
> > -		intel_dp_sink_dpms(intel_dp, DRM_MODE_DPMS_OFF);
> >  	}
> >  	DRM_DEBUG_KMS("active links %d\n", intel_dp->active_mst_links);
> >  }
> > @@ -196,6 +201,7 @@ static void intel_mst_pre_enable_dp(struct
> > intel_encoder *encoder,
> >  
> >  	DRM_DEBUG_KMS("active links %d\n", intel_dp->active_mst_links);
> >  
> > +	drm_dp_send_power_updown_phy(&intel_dp->mst_mgr, connector->port, 
> > true);
> >  	if (intel_dp->active_mst_links == 0)
> >  		intel_dig_port->base.pre_enable(&intel_dig_port->base,
> >  						pipe_config, NULL);
> 
>