drm/i915/mtl: Pin assignment for TypeC

Unlike previous platforms that used PORT_TX_DFLEXDPSP
for max_lane calculation, MTL uses only PORT_TX_DFLEXPA1
from which the max_lanes has to be calculated.

Bspec: 50235, 65380
Reviewed-by: Matt Atwood <matthew.s.atwood@intel.com>
Signed-off-by: Anusha Srivatsa <anusha.srivatsa@intel.com>
Signed-off-by: Jose Roberto de Souza <jose.souza@intel.com>
Signed-off-by: Mika Kahola <mika.kahola@intel.com>
Signed-off-by: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230428095433.4109054-13-mika.kahola@intel.com

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

@@ -16,6 +16,10 @@
 #include "intel_mg_phy_regs.h"
 #include "intel_tc.h"
 
+#define DP_PIN_ASSIGNMENT_C	0x3
+#define DP_PIN_ASSIGNMENT_D	0x4
+#define DP_PIN_ASSIGNMENT_E	0x5
+
 enum tc_port_mode {
 	TC_PORT_DISCONNECTED,
 	TC_PORT_TBT_ALT,
@@ -281,6 +285,27 @@ u32 intel_tc_port_get_pin_assignment_mask(struct intel_digital_port *dig_port)
 	       DP_PIN_ASSIGNMENT_SHIFT(tc->phy_fia_idx);
 }
 
+static int mtl_tc_port_get_pin_assignment_mask(struct intel_digital_port *dig_port)
+{
+	struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);
+	intel_wakeref_t wakeref;
+	u32 pin_mask;
+
+	with_intel_display_power(i915, POWER_DOMAIN_DISPLAY_CORE, wakeref)
+		pin_mask = intel_tc_port_get_pin_assignment_mask(dig_port);
+
+	switch (pin_mask) {
+	default:
+		MISSING_CASE(pin_mask);
+		fallthrough;
+	case DP_PIN_ASSIGNMENT_D:
+		return 2;
+	case DP_PIN_ASSIGNMENT_C:
+	case DP_PIN_ASSIGNMENT_E:
+		return 4;
+	}
+}
+
 int intel_tc_port_fia_max_lane_count(struct intel_digital_port *dig_port)
 {
 	struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);
@@ -294,6 +319,9 @@ int intel_tc_port_fia_max_lane_count(struct intel_digital_port *dig_port)
 
 	assert_tc_cold_blocked(tc);
 
+	if (DISPLAY_VER(i915) >= 14)
+		return mtl_tc_port_get_pin_assignment_mask(dig_port);
+
 	lane_mask = 0;
 	with_intel_display_power(i915, POWER_DOMAIN_DISPLAY_CORE, wakeref)
 		lane_mask = intel_tc_port_get_lane_mask(dig_port);