drm/i915/mtl: Readout Thunderbolt HW state

Readout hw state for Thunderbolt.
Reviewed-by: Radhakrishna Sripada <radhakrishna.sripada@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/20230428095433.4109054-9-mika.kahola@intel.com

drivers/gpu/drm/i915/display/intel_cx0_phy.c

@@ -2685,6 +2685,33 @@ static void intel_cx0pll_enable(struct intel_encoder *encoder,
 	intel_cx0_phy_transaction_end(encoder, wakeref);
 }
 
+int intel_mtl_tbt_calc_port_clock(struct intel_encoder *encoder)
+{
+	struct drm_i915_private *i915 = to_i915(encoder->base.dev);
+	u32 clock;
+	u32 val = intel_de_read(i915, XELPDP_PORT_CLOCK_CTL(encoder->port));
+
+	clock = REG_FIELD_GET(XELPDP_DDI_CLOCK_SELECT_MASK, val);
+
+	drm_WARN_ON(&i915->drm, !(val & XELPDP_FORWARD_CLOCK_UNGATE));
+	drm_WARN_ON(&i915->drm, !(val & XELPDP_TBT_CLOCK_REQUEST));
+	drm_WARN_ON(&i915->drm, !(val & XELPDP_TBT_CLOCK_ACK));
+
+	switch (clock) {
+	case XELPDP_DDI_CLOCK_SELECT_TBT_162:
+		return 162000;
+	case XELPDP_DDI_CLOCK_SELECT_TBT_270:
+		return 270000;
+	case XELPDP_DDI_CLOCK_SELECT_TBT_540:
+		return 540000;
+	case XELPDP_DDI_CLOCK_SELECT_TBT_810:
+		return 810000;
+	default:
+		MISSING_CASE(clock);
+		return 162000;
+	}
+}
+
 static int intel_mtl_tbt_clock_select(struct drm_i915_private *i915, int clock)
 {
 	switch (clock) {

drivers/gpu/drm/i915/display/intel_cx0_phy.h

@@ -42,5 +42,5 @@ int intel_cx0_phy_check_hdmi_link_rate(struct intel_hdmi *hdmi, int clock);
 void intel_cx0_phy_ddi_vswing_sequence(struct intel_encoder *encoder,
 				       const struct intel_crtc_state *crtc_state,
 				       u32 level);
-int intel_mtl_tbt_readout_hw_state(struct intel_encoder *encoder);
+int intel_mtl_tbt_calc_port_clock(struct intel_encoder *encoder);
 #endif /* __INTEL_CX0_PHY_H__ */

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

@@ -3852,8 +3852,11 @@ static void mtl_ddi_get_config(struct intel_encoder *encoder,
 {
 	struct drm_i915_private *i915 = to_i915(encoder->base.dev);
 	enum phy phy = intel_port_to_phy(i915, encoder->port);
+	struct intel_digital_port *dig_port = enc_to_dig_port(encoder);
 
-	if (intel_is_c10phy(i915, phy)) {
+	if (intel_tc_port_in_tbt_alt_mode(dig_port)) {
+		crtc_state->port_clock = intel_mtl_tbt_calc_port_clock(encoder);
+	} else if (intel_is_c10phy(i915, phy)) {
 		intel_c10pll_readout_hw_state(encoder, &crtc_state->cx0pll_state.c10);
 		intel_c10pll_dump_hw_state(i915, &crtc_state->cx0pll_state.c10);
 		crtc_state->port_clock = intel_c10pll_calc_port_clock(encoder, &crtc_state->cx0pll_state.c10);