drm/i915: add vlv_pipe_to_phy() helper to replace DPIO_PHY()

Add a helper with better typing and handing for bogus input, and better
in line with vlv_dig_port_to_channel(), vlv_dig_port_to_phy(), and
vlv_pipe_to_channel().
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231114104534.4180144-2-jani.nikula@intel.com

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

@@ -666,6 +666,20 @@ enum dpio_phy vlv_dig_port_to_phy(struct intel_digital_port *dig_port)
 	}
 }
 
+enum dpio_phy vlv_pipe_to_phy(enum pipe pipe)
+{
+	switch (pipe) {
+	default:
+		MISSING_CASE(pipe);
+		fallthrough;
+	case PIPE_A:
+	case PIPE_B:
+		return DPIO_PHY0;
+	case PIPE_C:
+		return DPIO_PHY1;
+	}
+}
+
 enum dpio_channel vlv_pipe_to_channel(enum pipe pipe)
 {
 	switch (pipe) {

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

@@ -44,6 +44,7 @@ u8 bxt_ddi_phy_get_lane_lat_optim_mask(struct intel_encoder *encoder);
 
 enum dpio_channel vlv_dig_port_to_channel(struct intel_digital_port *dig_port);
 enum dpio_phy vlv_dig_port_to_phy(struct intel_digital_port *dig_port);
+enum dpio_phy vlv_pipe_to_phy(enum pipe pipe);
 enum dpio_channel vlv_pipe_to_channel(enum pipe pipe);
 
 void chv_set_phy_signal_level(struct intel_encoder *encoder,
@@ -116,6 +117,10 @@ static inline enum dpio_phy vlv_dig_port_to_phy(struct intel_digital_port *dig_p
 {
 	return DPIO_PHY0;
 }
+static inline enum dpio_phy vlv_pipe_to_phy(enum pipe pipe)
+{
+	return DPIO_PHY0;
+}
 static inline enum dpio_channel vlv_pipe_to_channel(enum pipe pipe)
 {
 	return DPIO_CH0;

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

@@ -90,7 +90,7 @@ vlv_power_sequencer_kick(struct intel_dp *intel_dp)
 	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
 	enum pipe pipe = intel_dp->pps.pps_pipe;
 	bool pll_enabled, release_cl_override = false;
-	enum dpio_phy phy = DPIO_PHY(pipe);
+	enum dpio_phy phy = vlv_pipe_to_phy(pipe);
 	enum dpio_channel ch = vlv_pipe_to_channel(pipe);
 	u32 DP;
 

drivers/gpu/drm/i915/i915_reg.h

@@ -195,8 +195,6 @@
 #define  DPIO_SFR_BYPASS		(1 << 1)
 #define  DPIO_CMNRST			(1 << 0)
 
-#define DPIO_PHY(pipe)			((pipe) >> 1)
-
 /*
  * Per pipe/PLL DPIO regs
  */

drivers/gpu/drm/i915/vlv_sideband.c

@@ -229,7 +229,8 @@ static u32 vlv_dpio_phy_iosf_port(struct drm_i915_private *i915, enum dpio_phy p
 
 u32 vlv_dpio_read(struct drm_i915_private *i915, enum pipe pipe, int reg)
 {
-	u32 port = vlv_dpio_phy_iosf_port(i915, DPIO_PHY(pipe));
+	enum dpio_phy phy = vlv_pipe_to_phy(pipe);
+	u32 port = vlv_dpio_phy_iosf_port(i915, phy);
 	u32 val = 0;
 
 	vlv_sideband_rw(i915, DPIO_DEVFN, port, SB_MRD_NP, reg, &val);
@@ -248,7 +249,8 @@ u32 vlv_dpio_read(struct drm_i915_private *i915, enum pipe pipe, int reg)
 void vlv_dpio_write(struct drm_i915_private *i915,
 		    enum pipe pipe, int reg, u32 val)
 {
-	u32 port = vlv_dpio_phy_iosf_port(i915, DPIO_PHY(pipe));
+	enum dpio_phy phy = vlv_pipe_to_phy(pipe);
+	u32 port = vlv_dpio_phy_iosf_port(i915, phy);
 
 	vlv_sideband_rw(i915, DPIO_DEVFN, port, SB_MWR_NP, reg, &val);
 }