drm/i915/icl: Factor out combo PHY lane power setup helper

Factor out the combo PHY lane power configuration code to a separate
helper; it will be also needed by the next patch adding the same
configuration for DDI ports.

Add support for DDI ports and lane reversal as preparation for the next
patch.

The PWR_DOWN_LN_1 value is unspecified in the BSpec register description
so remove it.

v2:
- Fix up the wrong assumption that the encodings are the same for DDI
  and DSI ports. (Jani)
v3:
- Use intel_ instead of icl_ prefix. (Jani)
- Add required headers to intel_combo_phy.h after the upstream header
  refactoring.

Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Madhav Chauhan <madhav.chauhan@intel.com>
Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com> (v2)
Link: https://patchwork.freedesktop.org/patch/msgid/20190425185253.3197-1-imre.deak@intel.com

drivers/gpu/drm/i915/i915_reg.h

@@ -1813,7 +1813,6 @@ enum i915_power_well_id {
 #define  PWR_DOWN_LN_3			(0x8 << 4)
 #define  PWR_DOWN_LN_2_1_0		(0x7 << 4)
 #define  PWR_DOWN_LN_1_0		(0x3 << 4)
-#define  PWR_DOWN_LN_1			(0x2 << 4)
 #define  PWR_DOWN_LN_3_1		(0xa << 4)
 #define  PWR_DOWN_LN_3_1_0		(0xb << 4)
 #define  PWR_DOWN_LN_MASK		(0xf << 4)

drivers/gpu/drm/i915/icl_dsi.c

@@ -29,6 +29,7 @@
 #include <drm/drm_mipi_dsi.h>
 
 #include "intel_atomic.h"
+#include "intel_combo_phy.h"
 #include "intel_connector.h"
 #include "intel_ddi.h"
 #include "intel_dsi.h"
@@ -364,30 +365,10 @@ static void gen11_dsi_power_up_lanes(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);
 	enum port port;
-	u32 tmp;
-	u32 lane_mask;
-
-	switch (intel_dsi->lane_count) {
-	case 1:
-		lane_mask = PWR_DOWN_LN_3_1_0;
-		break;
-	case 2:
-		lane_mask = PWR_DOWN_LN_3_1;
-		break;
-	case 3:
-		lane_mask = PWR_DOWN_LN_3;
-		break;
-	case 4:
-	default:
-		lane_mask = PWR_UP_ALL_LANES;
-		break;
-	}
 
-	for_each_dsi_port(port, intel_dsi->ports) {
-		tmp = I915_READ(ICL_PORT_CL_DW10(port));
-		tmp &= ~PWR_DOWN_LN_MASK;
-		I915_WRITE(ICL_PORT_CL_DW10(port), tmp | lane_mask);
-	}
+	for_each_dsi_port(port, intel_dsi->ports)
+		intel_combo_phy_power_up_lanes(dev_priv, port, true,
+					       intel_dsi->lane_count, false);
 }
 
 static void gen11_dsi_config_phy_lanes_sequence(struct intel_encoder *encoder)

drivers/gpu/drm/i915/intel_combo_phy.c

@@ -204,6 +204,58 @@ static bool icl_combo_phy_verify_state(struct drm_i915_private *dev_priv,
 	return ret;
 }
 
+void intel_combo_phy_power_up_lanes(struct drm_i915_private *dev_priv,
+				    enum port port, bool is_dsi,
+				    int lane_count, bool lane_reversal)
+{
+	u8 lane_mask;
+	u32 val;
+
+	if (is_dsi) {
+		WARN_ON(lane_reversal);
+
+		switch (lane_count) {
+		case 1:
+			lane_mask = PWR_DOWN_LN_3_1_0;
+			break;
+		case 2:
+			lane_mask = PWR_DOWN_LN_3_1;
+			break;
+		case 3:
+			lane_mask = PWR_DOWN_LN_3;
+			break;
+		default:
+			MISSING_CASE(lane_count);
+			/* fall-through */
+		case 4:
+			lane_mask = PWR_UP_ALL_LANES;
+			break;
+		}
+	} else {
+		switch (lane_count) {
+		case 1:
+			lane_mask = lane_reversal ? PWR_DOWN_LN_2_1_0 :
+						    PWR_DOWN_LN_3_2_1;
+			break;
+		case 2:
+			lane_mask = lane_reversal ? PWR_DOWN_LN_1_0 :
+						    PWR_DOWN_LN_3_2;
+			break;
+		default:
+			MISSING_CASE(lane_count);
+			/* fall-through */
+		case 4:
+			lane_mask = PWR_UP_ALL_LANES;
+			break;
+		}
+	}
+
+	val = I915_READ(ICL_PORT_CL_DW10(port));
+	val &= ~PWR_DOWN_LN_MASK;
+	val |= lane_mask << PWR_DOWN_LN_SHIFT;
+	I915_WRITE(ICL_PORT_CL_DW10(port), val);
+}
+
 void icl_combo_phys_init(struct drm_i915_private *dev_priv)
 {
 	enum port port;

drivers/gpu/drm/i915/intel_combo_phy.h

@@ -6,11 +6,17 @@
 #ifndef __INTEL_COMBO_PHY_H__
 #define __INTEL_COMBO_PHY_H__
 
+#include <linux/types.h>
+#include <drm/i915_drm.h>
+
 struct drm_i915_private;
 
 void icl_combo_phys_init(struct drm_i915_private *dev_priv);
 void icl_combo_phys_uninit(struct drm_i915_private *dev_priv);
 void cnl_combo_phys_init(struct drm_i915_private *dev_priv);
 void cnl_combo_phys_uninit(struct drm_i915_private *dev_priv);
+void intel_combo_phy_power_up_lanes(struct drm_i915_private *dev_priv,
+				    enum port port, bool is_dsi,
+				    int lane_count, bool lane_reversal);
 
 #endif /* __INTEL_COMBO_PHY_H__ */