drm/amd/display: add support for three new square pattern variants from DP2.1 specs

[why]
DP2.1 specs has brought 3 new variants of sqaure patterns with different
pre-shoot and de-emphasis equalization requirements. The commit adds
logic to identify these variants and apply corresponding eqaulization
requirements into hardware lane settings.

Reviewed-by: George Shen <[e-mail]>
Acked-by: Jasdeep Dhillon <[e-mail]>
Signed-off-by: Wenjing Liu <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c

···
 	dp_retrain_link_dp_test(link, &link_settings, false);
 }
 
+static bool is_dp_phy_sqaure_pattern(enum dp_test_pattern test_pattern)
+{
+	return (DP_TEST_PATTERN_SQUARE_BEGIN <= test_pattern &&
+			test_pattern <= DP_TEST_PATTERN_SQUARE_END);
+}
+
 /* TODO Raven hbr2 compliance eye output is unstable
  * (toggling on and off) with debugger break
  * This caueses intermittent PHY automation failure
···
 	union lane_adjust dpcd_lane_adjust;
 	unsigned int lane;
 	struct link_training_settings link_training_settings;
+	unsigned char no_preshoot = 0;
+	unsigned char no_deemphasis = 0;
 
 	dpcd_test_pattern.raw = 0;
 	memset(dpcd_lane_adjustment, 0, sizeof(dpcd_lane_adjustment));
···
 	case PHY_TEST_PATTERN_264BIT_CUSTOM:
 		test_pattern = DP_TEST_PATTERN_264BIT_CUSTOM;
 		break;
-	case PHY_TEST_PATTERN_SQUARE_PULSE:
-		test_pattern = DP_TEST_PATTERN_SQUARE_PULSE;
+	case PHY_TEST_PATTERN_SQUARE:
+		test_pattern = DP_TEST_PATTERN_SQUARE;
+		break;
+	case PHY_TEST_PATTERN_SQUARE_PRESHOOT_DISABLED:
+		test_pattern = DP_TEST_PATTERN_SQUARE_PRESHOOT_DISABLED;
+		no_preshoot = 1;
+		break;
+	case PHY_TEST_PATTERN_SQUARE_DEEMPHASIS_DISABLED:
+		test_pattern = DP_TEST_PATTERN_SQUARE_DEEMPHASIS_DISABLED;
+		no_deemphasis = 1;
+		break;
+	case PHY_TEST_PATTERN_SQUARE_PRESHOOT_DEEMPHASIS_DISABLED:
+		test_pattern = DP_TEST_PATTERN_SQUARE_PRESHOOT_DEEMPHASIS_DISABLED;
+		no_preshoot = 1;
+		no_deemphasis = 1;
 		break;
 	default:
 		test_pattern = DP_TEST_PATTERN_VIDEO_MODE;
···
 				test_pattern_size);
 	}
 
-	if (test_pattern == DP_TEST_PATTERN_SQUARE_PULSE) {
+	if (is_dp_phy_sqaure_pattern(test_pattern)) {
 		test_pattern_size = 1; // Square pattern data is 1 byte (DP spec)
 		core_link_read_dpcd(
 				link,
···
 				((dpcd_post_cursor_2_adjustment >> (lane * 2)) & 0x03);
 		} else if (dp_get_link_encoding_format(&link->cur_link_settings) ==
 				DP_128b_132b_ENCODING) {
-			link_training_settings.hw_lane_settings[lane].FFE_PRESET.raw =
+			link_training_settings.hw_lane_settings[lane].FFE_PRESET.settings.level =
 					dpcd_lane_adjust.tx_ffe.PRESET_VALUE;
+			link_training_settings.hw_lane_settings[lane].FFE_PRESET.settings.no_preshoot = no_preshoot;
+			link_training_settings.hw_lane_settings[lane].FFE_PRESET.settings.no_deemphasis = no_deemphasis;
 		}
 	}
 
···
 		case DP_TEST_PATTERN_264BIT_CUSTOM:
 			pattern = PHY_TEST_PATTERN_264BIT_CUSTOM;
 			break;
-		case DP_TEST_PATTERN_SQUARE_PULSE:
-			pattern = PHY_TEST_PATTERN_SQUARE_PULSE;
+		case DP_TEST_PATTERN_SQUARE:
+			pattern = PHY_TEST_PATTERN_SQUARE;
+			break;
+		case DP_TEST_PATTERN_SQUARE_PRESHOOT_DISABLED:
+			pattern = PHY_TEST_PATTERN_SQUARE_PRESHOOT_DISABLED;
+			break;
+		case DP_TEST_PATTERN_SQUARE_DEEMPHASIS_DISABLED:
+			pattern = PHY_TEST_PATTERN_SQUARE_DEEMPHASIS_DISABLED;
+			break;
+		case DP_TEST_PATTERN_SQUARE_PRESHOOT_DEEMPHASIS_DISABLED:
+			pattern = PHY_TEST_PATTERN_SQUARE_PRESHOOT_DEEMPHASIS_DISABLED;
 			break;
 		default:
 			return false;
···
 			return false;
 
 		if (link->dpcd_caps.dpcd_rev.raw >= DPCD_REV_12) {
-#if defined(CONFIG_DRM_AMD_DC_DCN)
-			if (test_pattern == DP_TEST_PATTERN_SQUARE_PULSE)
+			if (is_dp_phy_sqaure_pattern(test_pattern))
 				core_link_write_dpcd(link,
 						DP_LINK_SQUARE_PATTERN,
 						p_custom_pattern,
 						1);
 
-#endif
 			/* tell receiver that we are sending qualification
 			 * pattern DP 1.2 or later - DP receiver's link quality
 			 * pattern is set using DPCD LINK_QUAL_LANEx_SET

drivers/gpu/drm/amd/display/dc/dc_dp_types.h

···
 #ifndef DP_128b_132b_TRAINING_AUX_RD_INTERVAL
 #define DP_128b_132b_TRAINING_AUX_RD_INTERVAL		0x2216
 #endif
+#ifndef DP_LINK_SQUARE_PATTERN
+#define DP_LINK_SQUARE_PATTERN				0x10F
+#endif
 #ifndef DP_CABLE_ATTRIBUTES_UPDATED_BY_DPRX
 #define DP_CABLE_ATTRIBUTES_UPDATED_BY_DPRX		0x2217
 #endif

drivers/gpu/drm/amd/display/dc/dcn31/dcn31_hpo_dp_link_encoder.c

···
 		REG_UPDATE(DP_DPHY_SYM32_CONTROL,
 				MODE, DP2_TEST_PATTERN);
 		break;
-	case DP_TEST_PATTERN_SQUARE_PULSE:
+	case DP_TEST_PATTERN_SQUARE:
+	case DP_TEST_PATTERN_SQUARE_PRESHOOT_DISABLED:
+	case DP_TEST_PATTERN_SQUARE_DEEMPHASIS_DISABLED:
+	case DP_TEST_PATTERN_SQUARE_PRESHOOT_DEEMPHASIS_DISABLED:
 		REG_SET(DP_DPHY_SYM32_TP_SQ_PULSE, 0,
 				TP_SQ_PULSE_WIDTH, tp_params->custom_pattern[0]);
 

drivers/gpu/drm/amd/display/include/dpcd_defs.h

···
 	PHY_TEST_PATTERN_PRBS23 = 0x30,
 	PHY_TEST_PATTERN_PRBS31 = 0x38,
 	PHY_TEST_PATTERN_264BIT_CUSTOM = 0x40,
-	PHY_TEST_PATTERN_SQUARE_PULSE = 0x48,
+	PHY_TEST_PATTERN_SQUARE = 0x48,
+	PHY_TEST_PATTERN_SQUARE_PRESHOOT_DISABLED = 0x49,
+	PHY_TEST_PATTERN_SQUARE_DEEMPHASIS_DISABLED = 0x4A,
+	PHY_TEST_PATTERN_SQUARE_PRESHOOT_DEEMPHASIS_DISABLED = 0x4B,
 };
 
 enum dpcd_test_dyn_range {

drivers/gpu/drm/amd/display/include/link_service_types.h

···
 	DP_TEST_PATTERN_PRBS23,
 	DP_TEST_PATTERN_PRBS31,
 	DP_TEST_PATTERN_264BIT_CUSTOM,
-	DP_TEST_PATTERN_SQUARE_PULSE,
+	DP_TEST_PATTERN_SQUARE_BEGIN,
+	DP_TEST_PATTERN_SQUARE = DP_TEST_PATTERN_SQUARE_BEGIN,
+	DP_TEST_PATTERN_SQUARE_PRESHOOT_DISABLED,
+	DP_TEST_PATTERN_SQUARE_DEEMPHASIS_DISABLED,
+	DP_TEST_PATTERN_SQUARE_PRESHOOT_DEEMPHASIS_DISABLED,
+	DP_TEST_PATTERN_SQUARE_END = DP_TEST_PATTERN_SQUARE_PRESHOOT_DEEMPHASIS_DISABLED,
 
 	/* Link Training Patterns */
 	DP_TEST_PATTERN_TRAINING_PATTERN1,