drm/i915/bxt: Assign PLL for pipe

Assign PLL for pipe (dependent on port attached to the pipe)

v2:
- fix incorrect encoder vs. new_encoder check for crtc (imre)

v3:
- warn and return error if no encoder is attached (imre)

Signed-off-by: Satheeshakrishna M <satheeshakrishna.m@intel.com> (v2)
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
[danvet: Don't move intel_ddi_get_crtc_new_encoder around.]
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_ddi.c

@@ -493,7 +493,7 @@ intel_ddi_get_crtc_encoder(struct drm_crtc *crtc)
 	return ret;
 }
 
-static struct intel_encoder *
+struct intel_encoder *
 intel_ddi_get_crtc_new_encoder(struct intel_crtc_state *crtc_state)
 {
 	struct intel_crtc *crtc = to_intel_crtc(crtc_state->base.crtc);

drivers/gpu/drm/i915/intel_display.c

@@ -4209,6 +4209,26 @@ struct intel_shared_dpll *intel_get_shared_dpll(struct intel_crtc *crtc,
 		goto found;
 	}
 
+	if (IS_BROXTON(dev_priv->dev)) {
+		/* PLL is attached to port in bxt */
+		struct intel_encoder *encoder;
+		struct intel_digital_port *intel_dig_port;
+
+		encoder = intel_ddi_get_crtc_new_encoder(crtc_state);
+		if (WARN_ON(!encoder))
+			return NULL;
+
+		intel_dig_port = enc_to_dig_port(&encoder->base);
+		/* 1:1 mapping between ports and PLLs */
+		i = (enum intel_dpll_id)intel_dig_port->port;
+		pll = &dev_priv->shared_dplls[i];
+		DRM_DEBUG_KMS("CRTC:%d using pre-allocated %s\n",
+			crtc->base.base.id, pll->name);
+		WARN_ON(pll->new_config->crtc_mask);
+
+		goto found;
+	}
+
 	for (i = 0; i < dev_priv->num_shared_dpll; i++) {
 		pll = &dev_priv->shared_dplls[i];
 

drivers/gpu/drm/i915/intel_drv.h

@@ -936,6 +936,8 @@ bool intel_ddi_connector_get_hw_state(struct intel_connector *intel_connector);
 void intel_ddi_fdi_disable(struct drm_crtc *crtc);
 void intel_ddi_get_config(struct intel_encoder *encoder,
 			  struct intel_crtc_state *pipe_config);
+struct intel_encoder *
+intel_ddi_get_crtc_new_encoder(struct intel_crtc_state *crtc_state);
 
 void intel_ddi_init_dp_buf_reg(struct intel_encoder *encoder);
 void intel_ddi_clock_get(struct intel_encoder *encoder,