drm/i915/icl: Ungate DSI clocks

Ungate the clocks on the selected port.
Signed-off-by: Madhav Chauhan <madhav.chauhan@intel.com>
Signed-off-by: Vandita Kulkarni <vandita.kulkarni@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/2a01b3158feda624f98581b780854fe3df8c328d.1543500286.git.jani.nikula@intel.com

drivers/gpu/drm/i915/icl_dsi.c

@@ -553,6 +553,23 @@ static void gen11_dsi_gate_clocks(struct intel_encoder *encoder)
 	mutex_unlock(&dev_priv->dpll_lock);
 }
 
+static void gen11_dsi_ungate_clocks(struct intel_encoder *encoder)
+{
+	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
+	struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
+	u32 tmp;
+	enum port port;
+
+	mutex_lock(&dev_priv->dpll_lock);
+	tmp = I915_READ(DPCLKA_CFGCR0_ICL);
+	for_each_dsi_port(port, intel_dsi->ports) {
+		tmp &= ~DPCLKA_CFGCR0_DDI_CLK_OFF(port);
+	}
+
+	I915_WRITE(DPCLKA_CFGCR0_ICL, tmp);
+	mutex_unlock(&dev_priv->dpll_lock);
+}
+
 static void
 gen11_dsi_configure_transcoder(struct intel_encoder *encoder,
 			       const struct intel_crtc_state *pipe_config)
@@ -1061,6 +1078,7 @@ static void gen11_dsi_disable_port(struct intel_encoder *encoder)
 	u32 tmp;
 	enum port port;
 
+	gen11_dsi_ungate_clocks(encoder);
 	for_each_dsi_port(port, intel_dsi->ports) {
 		tmp = I915_READ(DDI_BUF_CTL(port));
 		tmp &= ~DDI_BUF_CTL_ENABLE;
@@ -1072,6 +1090,7 @@ static void gen11_dsi_disable_port(struct intel_encoder *encoder)
 			DRM_ERROR("DDI port:%c buffer not idle\n",
 				  port_name(port));
 	}
+	gen11_dsi_ungate_clocks(encoder);
 }
 
 static void gen11_dsi_disable_io_power(struct intel_encoder *encoder)