drm/i915/display/adlp: Implement new step in the TC voltage swing prog sequence

TC voltage swing programming sequence was updated with a new step.

BSpec: 54956
Cc: stable@vger.kernel.org
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Clint Taylor <clinton.a.taylor@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Reviewed-by: Clint Taylor <Clinton.A.Taylor@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220113174826.50272-1-jose.souza@intel.com

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

@@ -1300,6 +1300,28 @@ static void tgl_dkl_phy_set_signal_levels(struct intel_encoder *encoder,
 
 		intel_de_rmw(dev_priv, DKL_TX_DPCNTL2(tc_port),
 			     DKL_TX_DP20BITMODE, 0);
+
+		if (IS_ALDERLAKE_P(dev_priv)) {
+			u32 val;
+
+			if (intel_crtc_has_type(crtc_state, INTEL_OUTPUT_HDMI)) {
+				if (ln == 0) {
+					val = DKL_TX_DPCNTL2_CFG_LOADGENSELECT_TX1(0);
+					val |= DKL_TX_DPCNTL2_CFG_LOADGENSELECT_TX2(2);
+				} else {
+					val = DKL_TX_DPCNTL2_CFG_LOADGENSELECT_TX1(3);
+					val |= DKL_TX_DPCNTL2_CFG_LOADGENSELECT_TX2(3);
+				}
+			} else {
+				val = DKL_TX_DPCNTL2_CFG_LOADGENSELECT_TX1(0);
+				val |= DKL_TX_DPCNTL2_CFG_LOADGENSELECT_TX2(0);
+			}
+
+			intel_de_rmw(dev_priv, DKL_TX_DPCNTL2(tc_port),
+				     DKL_TX_DPCNTL2_CFG_LOADGENSELECT_TX1_MASK |
+				     DKL_TX_DPCNTL2_CFG_LOADGENSELECT_TX2_MASK,
+				     val);
+		}
 	}
 }
 

drivers/gpu/drm/i915/i915_reg.h

@@ -9968,8 +9968,12 @@ enum skl_power_gate {
 						     _DKL_PHY2_BASE) + \
 						     _DKL_TX_DPCNTL1)
 
-#define _DKL_TX_DPCNTL2				0x2C8
-#define  DKL_TX_DP20BITMODE				(1 << 2)
+#define _DKL_TX_DPCNTL2					0x2C8
+#define  DKL_TX_DP20BITMODE				REG_BIT(2)
+#define  DKL_TX_DPCNTL2_CFG_LOADGENSELECT_TX1_MASK	REG_GENMASK(4, 3)
+#define  DKL_TX_DPCNTL2_CFG_LOADGENSELECT_TX1(val)	REG_FIELD_PREP(DKL_TX_DPCNTL2_CFG_LOADGENSELECT_TX1_MASK, (val))
+#define  DKL_TX_DPCNTL2_CFG_LOADGENSELECT_TX2_MASK	REG_GENMASK(6, 5)
+#define  DKL_TX_DPCNTL2_CFG_LOADGENSELECT_TX2(val)	REG_FIELD_PREP(DKL_TX_DPCNTL2_CFG_LOADGENSELECT_TX2_MASK, (val))
 #define DKL_TX_DPCNTL2(tc_port) _MMIO(_PORT(tc_port, \
 						     _DKL_PHY1_BASE, \
 						     _DKL_PHY2_BASE) + \