drm/i915/mtl: Enabling/disabling sequence Thunderbolt pll

Enabling and disabling sequence for Thunderbolt PLL.

Bspec: 64568

v2: Use intel_de_wait_for_register() (RK)
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/20230428095433.4109054-8-mika.kahola@intel.com

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

@@ -2609,8 +2609,8 @@ static u32 intel_cx0_get_pclk_pll_ack(u8 lane_mask)
 	return val;
 }
 
-void intel_cx0pll_enable(struct intel_encoder *encoder,
-			 const struct intel_crtc_state *crtc_state)
+static void intel_cx0pll_enable(struct intel_encoder *encoder,
+				const struct intel_crtc_state *crtc_state)
 {
 	struct drm_i915_private *i915 = to_i915(encoder->base.dev);
 	enum phy phy = intel_port_to_phy(i915, encoder->port);
@@ -2685,7 +2685,86 @@ void intel_cx0pll_enable(struct intel_encoder *encoder,
 	intel_cx0_phy_transaction_end(encoder, wakeref);
 }
 
-void intel_cx0pll_disable(struct intel_encoder *encoder)
+static int intel_mtl_tbt_clock_select(struct drm_i915_private *i915, int clock)
+{
+	switch (clock) {
+	case 162000:
+		return XELPDP_DDI_CLOCK_SELECT_TBT_162;
+	case 270000:
+		return XELPDP_DDI_CLOCK_SELECT_TBT_270;
+	case 540000:
+		return XELPDP_DDI_CLOCK_SELECT_TBT_540;
+	case 810000:
+		return XELPDP_DDI_CLOCK_SELECT_TBT_810;
+	default:
+		MISSING_CASE(clock);
+		return XELPDP_DDI_CLOCK_SELECT_TBT_162;
+	}
+}
+
+static void intel_mtl_tbt_pll_enable(struct intel_encoder *encoder,
+				     const struct intel_crtc_state *crtc_state)
+{
+	struct drm_i915_private *i915 = to_i915(encoder->base.dev);
+	enum phy phy = intel_port_to_phy(i915, encoder->port);
+	u32 val = 0;
+
+	/*
+	 * 1. Program PORT_CLOCK_CTL REGISTER to configure
+	 * clock muxes, gating and SSC
+	 */
+	val |= XELPDP_DDI_CLOCK_SELECT(intel_mtl_tbt_clock_select(i915, crtc_state->port_clock));
+	val |= XELPDP_FORWARD_CLOCK_UNGATE;
+	intel_de_rmw(i915, XELPDP_PORT_CLOCK_CTL(encoder->port),
+		     XELPDP_DDI_CLOCK_SELECT_MASK | XELPDP_FORWARD_CLOCK_UNGATE, val);
+
+	/* 2. Read back PORT_CLOCK_CTL REGISTER */
+	val = intel_de_read(i915, XELPDP_PORT_CLOCK_CTL(encoder->port));
+
+	/*
+	 * 3. Follow the Display Voltage Frequency Switching - Sequence
+	 * Before Frequency Change. We handle this step in bxt_set_cdclk().
+	 */
+
+	/*
+	 * 4. Set PORT_CLOCK_CTL register TBT CLOCK Request to "1" to enable PLL.
+	 */
+	val |= XELPDP_TBT_CLOCK_REQUEST;
+	intel_de_write(i915, XELPDP_PORT_CLOCK_CTL(encoder->port), val);
+
+	/* 5. Poll on PORT_CLOCK_CTL TBT CLOCK Ack == "1". */
+	if (__intel_de_wait_for_register(i915, XELPDP_PORT_CLOCK_CTL(encoder->port),
+					 XELPDP_TBT_CLOCK_ACK,
+					 XELPDP_TBT_CLOCK_ACK,
+					 100, 0, NULL))
+		drm_warn(&i915->drm, "[ENCODER:%d:%s][%c] PHY PLL not locked after 100us.\n",
+			 encoder->base.base.id, encoder->base.name, phy_name(phy));
+
+	/*
+	 * 6. Follow the Display Voltage Frequency Switching Sequence After
+	 * Frequency Change. We handle this step in bxt_set_cdclk().
+	 */
+
+	/*
+	 * 7. Program DDI_CLK_VALFREQ to match intended DDI
+	 * clock frequency.
+	 */
+	intel_de_write(i915, DDI_CLK_VALFREQ(encoder->port),
+		       crtc_state->port_clock);
+}
+
+void intel_mtl_pll_enable(struct intel_encoder *encoder,
+			  const struct intel_crtc_state *crtc_state)
+{
+	struct intel_digital_port *dig_port = enc_to_dig_port(encoder);
+
+	if (intel_tc_port_in_tbt_alt_mode(dig_port))
+		intel_mtl_tbt_pll_enable(encoder, crtc_state);
+	else
+		intel_cx0pll_enable(encoder, crtc_state);
+}
+
+static void intel_cx0pll_disable(struct intel_encoder *encoder)
 {
 	struct drm_i915_private *i915 = to_i915(encoder->base.dev);
 	enum phy phy = intel_port_to_phy(i915, encoder->port);
@@ -2737,6 +2816,56 @@ void intel_cx0pll_disable(struct intel_encoder *encoder)
 	intel_cx0_phy_transaction_end(encoder, wakeref);
 }
 
+static void intel_mtl_tbt_pll_disable(struct intel_encoder *encoder)
+{
+	struct drm_i915_private *i915 = to_i915(encoder->base.dev);
+	enum phy phy = intel_port_to_phy(i915, encoder->port);
+
+	/*
+	 * 1. Follow the Display Voltage Frequency Switching Sequence Before
+	 * Frequency Change. We handle this step in bxt_set_cdclk().
+	 */
+
+	/*
+	 * 2. Set PORT_CLOCK_CTL register TBT CLOCK Request to "0" to disable PLL.
+	 */
+	intel_de_rmw(i915, XELPDP_PORT_CLOCK_CTL(encoder->port),
+		     XELPDP_TBT_CLOCK_REQUEST, 0);
+
+	/* 3. Poll on PORT_CLOCK_CTL TBT CLOCK Ack == "0". */
+	if (__intel_de_wait_for_register(i915, XELPDP_PORT_CLOCK_CTL(encoder->port),
+					 XELPDP_TBT_CLOCK_ACK,
+					 ~XELPDP_TBT_CLOCK_ACK,
+					 10, 0, NULL))
+		drm_warn(&i915->drm, "[ENCODER:%d:%s][%c] PHY PLL not unlocked after 10us.\n",
+			 encoder->base.base.id, encoder->base.name, phy_name(phy));
+
+	/*
+	 * 4. Follow the Display Voltage Frequency Switching Sequence After
+	 * Frequency Change. We handle this step in bxt_set_cdclk().
+	 */
+
+	/*
+	 * 5. Program PORT CLOCK CTRL register to disable and gate clocks
+	 */
+	intel_de_rmw(i915, XELPDP_PORT_CLOCK_CTL(encoder->port),
+		     XELPDP_DDI_CLOCK_SELECT_MASK |
+		     XELPDP_FORWARD_CLOCK_UNGATE, 0);
+
+	/* 6. Program DDI_CLK_VALFREQ to 0. */
+	intel_de_write(i915, DDI_CLK_VALFREQ(encoder->port), 0);
+}
+
+void intel_mtl_pll_disable(struct intel_encoder *encoder)
+{
+	struct intel_digital_port *dig_port = enc_to_dig_port(encoder);
+
+	if (intel_tc_port_in_tbt_alt_mode(dig_port))
+		intel_mtl_tbt_pll_disable(encoder);
+	else
+		intel_cx0pll_disable(encoder);
+}
+
 void intel_c10pll_state_verify(struct intel_atomic_state *state,
 			       struct intel_crtc_state *new_crtc_state)
 {

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

@@ -19,9 +19,9 @@ struct intel_crtc_state;
 enum phy;
 
 bool intel_is_c10phy(struct drm_i915_private *dev_priv, enum phy phy);
-void intel_cx0pll_enable(struct intel_encoder *encoder,
-			 const struct intel_crtc_state *crtc_state);
-void intel_cx0pll_disable(struct intel_encoder *encoder);
+void intel_mtl_pll_enable(struct intel_encoder *encoder,
+			  const struct intel_crtc_state *crtc_state);
+void intel_mtl_pll_disable(struct intel_encoder *encoder);
 void intel_c10pll_readout_hw_state(struct intel_encoder *encoder, struct intel_c10pll_state *pll_state);
 int intel_cx0pll_calc_state(struct intel_crtc_state *crtc_state, struct intel_encoder *encoder);
 void intel_c10pll_dump_hw_state(struct drm_i915_private *dev_priv,
@@ -42,4 +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);
 #endif /* __INTEL_CX0_PHY_H__ */

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

@@ -4779,8 +4779,8 @@ void intel_ddi_init(struct drm_i915_private *dev_priv, enum port port)
 	encoder->pipe_mask = ~0;
 
 	if (DISPLAY_VER(dev_priv) >= 14) {
-		encoder->enable_clock = intel_cx0pll_enable;
-		encoder->disable_clock = intel_cx0pll_disable;
+		encoder->enable_clock = intel_mtl_pll_enable;
+		encoder->disable_clock = intel_mtl_pll_disable;
 		encoder->get_config = mtl_ddi_get_config;
 	} else if (IS_DG2(dev_priv)) {
 		encoder->enable_clock = intel_mpllb_enable;