drm/i915: Introduce ilk_pch_disable() and ilk_pch_post_disable()

Hoover the remaining open coded PCH modeset sequence bits
out from ilk_crtc_disable(). Somewhat annoyingly the
enable vs. disable is a bit asymmetric so we need two
functions for the disable case.

Cc: Dave Airlie <airlied@redhat.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211015071625.593-8-ville.syrjala@linux.intel.comReviewed-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/i915/display/intel_display.c

@@ -2287,33 +2287,12 @@ static void ilk_crtc_disable(struct intel_atomic_state *state,
 	ilk_pfit_disable(old_crtc_state);
 
 	if (old_crtc_state->has_pch_encoder)
-		ilk_fdi_disable(crtc);
+		ilk_pch_disable(state, crtc);
 
 	intel_encoders_post_disable(state, crtc);
 
-	if (old_crtc_state->has_pch_encoder) {
-		ilk_disable_pch_transcoder(crtc);
-
-		if (HAS_PCH_CPT(dev_priv)) {
-			i915_reg_t reg;
-			u32 temp;
-
-			/* disable TRANS_DP_CTL */
-			reg = TRANS_DP_CTL(pipe);
-			temp = intel_de_read(dev_priv, reg);
-			temp &= ~(TRANS_DP_OUTPUT_ENABLE |
-				  TRANS_DP_PORT_SEL_MASK);
-			temp |= TRANS_DP_PORT_SEL_NONE;
-			intel_de_write(dev_priv, reg, temp);
-
-			/* disable DPLL_SEL */
-			temp = intel_de_read(dev_priv, PCH_DPLL_SEL);
-			temp &= ~(TRANS_DPLL_ENABLE(pipe) | TRANS_DPLLB_SEL(pipe));
-			intel_de_write(dev_priv, PCH_DPLL_SEL, temp);
-		}
-
-		ilk_fdi_pll_disable(crtc);
-	}
+	if (old_crtc_state->has_pch_encoder)
+		ilk_pch_post_disable(state, crtc);
 
 	intel_set_cpu_fifo_underrun_reporting(dev_priv, pipe, true);
 	intel_set_pch_fifo_underrun_reporting(dev_priv, pipe, true);

drivers/gpu/drm/i915/display/intel_pch_display.c

@@ -179,7 +179,7 @@ static void ilk_enable_pch_transcoder(const struct intel_crtc_state *crtc_state)
 			pipe_name(pipe));
 }
 
-void ilk_disable_pch_transcoder(struct intel_crtc *crtc)
+static void ilk_disable_pch_transcoder(struct intel_crtc *crtc)
 {
 	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
 	enum pipe pipe = crtc->pipe;
@@ -299,6 +299,41 @@ void ilk_pch_enable(struct intel_atomic_state *state,
 	ilk_enable_pch_transcoder(crtc_state);
 }
 
+void ilk_pch_disable(struct intel_atomic_state *state,
+		     struct intel_crtc *crtc)
+{
+	ilk_fdi_disable(crtc);
+}
+
+void ilk_pch_post_disable(struct intel_atomic_state *state,
+			  struct intel_crtc *crtc)
+{
+	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+	enum pipe pipe = crtc->pipe;
+
+	ilk_disable_pch_transcoder(crtc);
+
+	if (HAS_PCH_CPT(dev_priv)) {
+		i915_reg_t reg;
+		u32 temp;
+
+		/* disable TRANS_DP_CTL */
+		reg = TRANS_DP_CTL(pipe);
+		temp = intel_de_read(dev_priv, reg);
+		temp &= ~(TRANS_DP_OUTPUT_ENABLE |
+			  TRANS_DP_PORT_SEL_MASK);
+		temp |= TRANS_DP_PORT_SEL_NONE;
+		intel_de_write(dev_priv, reg, temp);
+
+		/* disable DPLL_SEL */
+		temp = intel_de_read(dev_priv, PCH_DPLL_SEL);
+		temp &= ~(TRANS_DPLL_ENABLE(pipe) | TRANS_DPLLB_SEL(pipe));
+		intel_de_write(dev_priv, PCH_DPLL_SEL, temp);
+	}
+
+	ilk_fdi_pll_disable(crtc);
+}
+
 static void ilk_pch_clock_get(struct intel_crtc_state *crtc_state)
 {
 	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);

drivers/gpu/drm/i915/display/intel_pch_display.h

@@ -11,9 +11,12 @@ struct intel_atomic_state;
 struct intel_crtc;
 struct intel_crtc_state;
 
-void ilk_disable_pch_transcoder(struct intel_crtc *crtc);
 void ilk_pch_enable(struct intel_atomic_state *state,
 		    struct intel_crtc *crtc);
+void ilk_pch_disable(struct intel_atomic_state *state,
+		     struct intel_crtc *crtc);
+void ilk_pch_post_disable(struct intel_atomic_state *state,
+			  struct intel_crtc *crtc);
 void ilk_pch_get_config(struct intel_crtc_state *crtc_state);
 
 void lpt_disable_pch_transcoder(struct drm_i915_private *dev_priv);