drm/amd/display: Fix DP2 link training failure with RCO

[Why]
When RCO is enabled for symclk32_le we get failures during
DP2 link traing compliance tests.

[How]
Break out symclk32_le RCO into a separate function that is
called for hpo when link is enabled/disabled.
Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Acked-by: Alan Liu <haoping.liu@amd.com>
Signed-off-by: Daniel Miess <daniel.miess@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dcn31/dcn31_dccg.c

@@ -284,19 +284,11 @@ void dccg31_enable_symclk32_le(
 	/* select one of the PHYD32CLKs as the source for symclk32_le */
 	switch (hpo_le_inst) {
 	case 0:
-		if (dccg->ctx->dc->debug.root_clock_optimization.bits.symclk32_le)
-			REG_UPDATE_2(DCCG_GATE_DISABLE_CNTL3,
-					SYMCLK32_LE0_GATE_DISABLE, 1,
-					SYMCLK32_ROOT_LE0_GATE_DISABLE, 1);
 		REG_UPDATE_2(SYMCLK32_LE_CNTL,
 				SYMCLK32_LE0_SRC_SEL, phyd32clk,
 				SYMCLK32_LE0_EN, 1);
 		break;
 	case 1:
-		if (dccg->ctx->dc->debug.root_clock_optimization.bits.symclk32_le)
-			REG_UPDATE_2(DCCG_GATE_DISABLE_CNTL3,
-					SYMCLK32_LE1_GATE_DISABLE, 1,
-					SYMCLK32_ROOT_LE1_GATE_DISABLE, 1);
 		REG_UPDATE_2(SYMCLK32_LE_CNTL,
 				SYMCLK32_LE1_SRC_SEL, phyd32clk,
 				SYMCLK32_LE1_EN, 1);
@@ -319,19 +311,38 @@ void dccg31_disable_symclk32_le(
 		REG_UPDATE_2(SYMCLK32_LE_CNTL,
 				SYMCLK32_LE0_SRC_SEL, 0,
 				SYMCLK32_LE0_EN, 0);
-		if (dccg->ctx->dc->debug.root_clock_optimization.bits.symclk32_le)
-			REG_UPDATE_2(DCCG_GATE_DISABLE_CNTL3,
-					SYMCLK32_LE0_GATE_DISABLE, 0,
-					SYMCLK32_ROOT_LE0_GATE_DISABLE, 0);
 		break;
 	case 1:
 		REG_UPDATE_2(SYMCLK32_LE_CNTL,
 				SYMCLK32_LE1_SRC_SEL, 0,
 				SYMCLK32_LE1_EN, 0);
-		if (dccg->ctx->dc->debug.root_clock_optimization.bits.symclk32_le)
-			REG_UPDATE_2(DCCG_GATE_DISABLE_CNTL3,
-					SYMCLK32_LE1_GATE_DISABLE, 0,
-					SYMCLK32_ROOT_LE1_GATE_DISABLE, 0);
+		break;
+	default:
+		BREAK_TO_DEBUGGER();
+		return;
+	}
+}
+
+void dccg31_set_symclk32_le_root_clock_gating(
+		struct dccg *dccg,
+		int hpo_le_inst,
+		bool enable)
+{
+	struct dcn_dccg *dccg_dcn = TO_DCN_DCCG(dccg);
+
+	if (!dccg->ctx->dc->debug.root_clock_optimization.bits.symclk32_le)
+		return;
+
+	switch (hpo_le_inst) {
+	case 0:
+		REG_UPDATE_2(DCCG_GATE_DISABLE_CNTL3,
+				SYMCLK32_LE0_GATE_DISABLE, enable ? 1 : 0,
+				SYMCLK32_ROOT_LE0_GATE_DISABLE, enable ? 1 : 0);
+		break;
+	case 1:
+		REG_UPDATE_2(DCCG_GATE_DISABLE_CNTL3,
+				SYMCLK32_LE1_GATE_DISABLE, enable ? 1 : 0,
+				SYMCLK32_ROOT_LE1_GATE_DISABLE, enable ? 1 : 0);
 		break;
 	default:
 		BREAK_TO_DEBUGGER();
@@ -660,10 +671,8 @@ void dccg31_init(struct dccg *dccg)
 	dccg31_disable_symclk32_se(dccg, 2);
 	dccg31_disable_symclk32_se(dccg, 3);
 
-	if (dccg->ctx->dc->debug.root_clock_optimization.bits.symclk32_le) {
-		dccg31_disable_symclk32_le(dccg, 0);
-		dccg31_disable_symclk32_le(dccg, 1);
-	}
+	dccg31_set_symclk32_le_root_clock_gating(dccg, 0, false);
+	dccg31_set_symclk32_le_root_clock_gating(dccg, 1, false);
 
 	if (dccg->ctx->dc->debug.root_clock_optimization.bits.dpstream) {
 		dccg31_disable_dpstreamclk(dccg, 0);

drivers/gpu/drm/amd/display/dc/dcn31/dcn31_dccg.h

@@ -179,6 +179,11 @@ void dccg31_disable_symclk32_le(
 		struct dccg *dccg,
 		int hpo_le_inst);
 
+void dccg31_set_symclk32_le_root_clock_gating(
+		struct dccg *dccg,
+		int hpo_le_inst,
+		bool enable);
+
 void dccg31_set_physymclk(
 		struct dccg *dccg,
 		int phy_inst,

drivers/gpu/drm/amd/display/dc/dcn314/dcn314_dccg.c

@@ -362,6 +362,7 @@ static const struct dccg_funcs dccg314_funcs = {
 	.disable_symclk32_se = dccg31_disable_symclk32_se,
 	.enable_symclk32_le = dccg31_enable_symclk32_le,
 	.disable_symclk32_le = dccg31_disable_symclk32_le,
+	.set_symclk32_le_root_clock_gating = dccg31_set_symclk32_le_root_clock_gating,
 	.set_physymclk = dccg31_set_physymclk,
 	.set_dtbclk_dto = dccg314_set_dtbclk_dto,
 	.set_audio_dtbclk_dto = dccg31_set_audio_dtbclk_dto,

drivers/gpu/drm/amd/display/dc/inc/hw/dccg.h

@@ -123,6 +123,11 @@ struct dccg_funcs {
 			struct dccg *dccg,
 			int hpo_le_inst);
 
+	void (*set_symclk32_le_root_clock_gating)(
+			struct dccg *dccg,
+			int hpo_le_inst,
+			bool enable);
+
 	void (*set_physymclk)(
 			struct dccg *dccg,
 			int phy_inst,

drivers/gpu/drm/amd/display/dc/link/hwss/link_hwss_hpo_dp.c

@@ -108,6 +108,11 @@ static void enable_hpo_dp_link_output(struct dc_link *link,
 		enum clock_source_id clock_source,
 		const struct dc_link_settings *link_settings)
 {
+	if (link->dc->res_pool->dccg->funcs->set_symclk32_le_root_clock_gating)
+		link->dc->res_pool->dccg->funcs->set_symclk32_le_root_clock_gating(
+				link->dc->res_pool->dccg,
+				link_res->hpo_dp_link_enc->inst,
+				true);
 	link_res->hpo_dp_link_enc->funcs->enable_link_phy(
 			link_res->hpo_dp_link_enc,
 			link_settings,
@@ -122,6 +127,11 @@ static void disable_hpo_dp_link_output(struct dc_link *link,
 		link_res->hpo_dp_link_enc->funcs->link_disable(link_res->hpo_dp_link_enc);
 		link_res->hpo_dp_link_enc->funcs->disable_link_phy(
 				link_res->hpo_dp_link_enc, signal);
+		if (link->dc->res_pool->dccg->funcs->set_symclk32_le_root_clock_gating)
+			link->dc->res_pool->dccg->funcs->set_symclk32_le_root_clock_gating(
+					link->dc->res_pool->dccg,
+					link_res->hpo_dp_link_enc->inst,
+					false);
 }
 
 static void set_hpo_dp_link_test_pattern(struct dc_link *link,