drm/amd/display: add safe_to_lower support to dcn wm programming

This will prevent watermarks from lowering when unsafe to do so.
Signed-off-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
Reviewed-by: Charlene Liu <Charlene.Liu@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hubbub.c

@@ -193,7 +193,8 @@ static uint32_t convert_and_clamp(
 void hubbub1_program_watermarks(
 		struct hubbub *hubbub,
 		struct dcn_watermark_set *watermarks,
-		unsigned int refclk_mhz)
+		unsigned int refclk_mhz,
+		bool safe_to_lower)
 {
 	uint32_t force_en = hubbub->ctx->dc->debug.disable_stutter ? 1 : 0;
 	/*
@@ -207,6 +208,8 @@ void hubbub1_program_watermarks(
 
 	/* Repeat for water mark set A, B, C and D. */
 	/* clock state A */
+	if (safe_to_lower || watermarks->a.urgent_ns > hubbub->watermarks.a.urgent_ns) {
+		hubbub->watermarks.a.urgent_ns = watermarks->a.urgent_ns;
 		prog_wm_value = convert_and_clamp(watermarks->a.urgent_ns,
 				refclk_mhz, 0x1fffff);
 		REG_WRITE(DCHUBBUB_ARB_DATA_URGENCY_WATERMARK_A, prog_wm_value);
@@ -214,15 +217,23 @@ void hubbub1_program_watermarks(
 		DC_LOG_BANDWIDTH_CALCS("URGENCY_WATERMARK_A calculated =%d\n"
 			"HW register value = 0x%x\n",
 			watermarks->a.urgent_ns, prog_wm_value);
+	}
 
+	if (safe_to_lower || watermarks->a.pte_meta_urgent_ns > hubbub->watermarks.a.pte_meta_urgent_ns) {
+		hubbub->watermarks.a.pte_meta_urgent_ns = watermarks->a.pte_meta_urgent_ns;
 		prog_wm_value = convert_and_clamp(watermarks->a.pte_meta_urgent_ns,
 				refclk_mhz, 0x1fffff);
 		REG_WRITE(DCHUBBUB_ARB_PTE_META_URGENCY_WATERMARK_A, prog_wm_value);
 		DC_LOG_BANDWIDTH_CALCS("PTE_META_URGENCY_WATERMARK_A calculated =%d\n"
 			"HW register value = 0x%x\n",
 			watermarks->a.pte_meta_urgent_ns, prog_wm_value);
+	}
 
 	if (REG(DCHUBBUB_ARB_ALLOW_SR_ENTER_WATERMARK_A)) {
+		if (safe_to_lower || watermarks->a.cstate_pstate.cstate_enter_plus_exit_ns
+				> hubbub->watermarks.a.cstate_pstate.cstate_enter_plus_exit_ns) {
+			hubbub->watermarks.a.cstate_pstate.cstate_enter_plus_exit_ns =
+					watermarks->a.cstate_pstate.cstate_enter_plus_exit_ns;
 			prog_wm_value = convert_and_clamp(
 					watermarks->a.cstate_pstate.cstate_enter_plus_exit_ns,
 					refclk_mhz, 0x1fffff);
@@ -230,8 +241,12 @@ void hubbub1_program_watermarks(
 			DC_LOG_BANDWIDTH_CALCS("SR_ENTER_EXIT_WATERMARK_A calculated =%d\n"
 				"HW register value = 0x%x\n",
 				watermarks->a.cstate_pstate.cstate_enter_plus_exit_ns, prog_wm_value);
+		}
 
-
+		if (safe_to_lower || watermarks->a.cstate_pstate.cstate_exit_ns
+				> hubbub->watermarks.a.cstate_pstate.cstate_exit_ns) {
+			hubbub->watermarks.a.cstate_pstate.cstate_exit_ns =
+					watermarks->a.cstate_pstate.cstate_exit_ns;
 			prog_wm_value = convert_and_clamp(
 					watermarks->a.cstate_pstate.cstate_exit_ns,
 					refclk_mhz, 0x1fffff);
@@ -240,7 +255,12 @@ void hubbub1_program_watermarks(
 				"HW register value = 0x%x\n",
 				watermarks->a.cstate_pstate.cstate_exit_ns, prog_wm_value);
 		}
+	}
 
+	if (safe_to_lower || watermarks->a.cstate_pstate.pstate_change_ns
+			> hubbub->watermarks.a.cstate_pstate.pstate_change_ns) {
+		hubbub->watermarks.a.cstate_pstate.pstate_change_ns =
+				watermarks->a.cstate_pstate.pstate_change_ns;
 		prog_wm_value = convert_and_clamp(
 				watermarks->a.cstate_pstate.pstate_change_ns,
 				refclk_mhz, 0x1fffff);
@@ -248,36 +268,48 @@ void hubbub1_program_watermarks(
 		DC_LOG_BANDWIDTH_CALCS("DRAM_CLK_CHANGE_WATERMARK_A calculated =%d\n"
 			"HW register value = 0x%x\n\n",
 			watermarks->a.cstate_pstate.pstate_change_ns, prog_wm_value);
-
+	}
 
 	/* clock state B */
-	prog_wm_value = convert_and_clamp(
-			watermarks->b.urgent_ns, refclk_mhz, 0x1fffff);
+	if (safe_to_lower || watermarks->b.urgent_ns > hubbub->watermarks.b.urgent_ns) {
+		hubbub->watermarks.b.urgent_ns = watermarks->b.urgent_ns;
+		prog_wm_value = convert_and_clamp(watermarks->b.urgent_ns,
+				refclk_mhz, 0x1fffff);
 		REG_WRITE(DCHUBBUB_ARB_DATA_URGENCY_WATERMARK_B, prog_wm_value);
+
 		DC_LOG_BANDWIDTH_CALCS("URGENCY_WATERMARK_B calculated =%d\n"
 			"HW register value = 0x%x\n",
 			watermarks->b.urgent_ns, prog_wm_value);
+	}
 
-
-	prog_wm_value = convert_and_clamp(
-			watermarks->b.pte_meta_urgent_ns,
+	if (safe_to_lower || watermarks->b.pte_meta_urgent_ns > hubbub->watermarks.b.pte_meta_urgent_ns) {
+		hubbub->watermarks.b.pte_meta_urgent_ns = watermarks->b.pte_meta_urgent_ns;
+		prog_wm_value = convert_and_clamp(watermarks->b.pte_meta_urgent_ns,
 				refclk_mhz, 0x1fffff);
 		REG_WRITE(DCHUBBUB_ARB_PTE_META_URGENCY_WATERMARK_B, prog_wm_value);
 		DC_LOG_BANDWIDTH_CALCS("PTE_META_URGENCY_WATERMARK_B calculated =%d\n"
 			"HW register value = 0x%x\n",
 			watermarks->b.pte_meta_urgent_ns, prog_wm_value);
-
+	}
 
 	if (REG(DCHUBBUB_ARB_ALLOW_SR_ENTER_WATERMARK_B)) {
+		if (safe_to_lower || watermarks->b.cstate_pstate.cstate_enter_plus_exit_ns
+				> hubbub->watermarks.b.cstate_pstate.cstate_enter_plus_exit_ns) {
+			hubbub->watermarks.b.cstate_pstate.cstate_enter_plus_exit_ns =
+					watermarks->b.cstate_pstate.cstate_enter_plus_exit_ns;
 			prog_wm_value = convert_and_clamp(
 					watermarks->b.cstate_pstate.cstate_enter_plus_exit_ns,
 					refclk_mhz, 0x1fffff);
 			REG_WRITE(DCHUBBUB_ARB_ALLOW_SR_ENTER_WATERMARK_B, prog_wm_value);
-		DC_LOG_BANDWIDTH_CALCS("SR_ENTER_WATERMARK_B calculated =%d\n"
+			DC_LOG_BANDWIDTH_CALCS("SR_ENTER_EXIT_WATERMARK_B calculated =%d\n"
 				"HW register value = 0x%x\n",
 				watermarks->b.cstate_pstate.cstate_enter_plus_exit_ns, prog_wm_value);
+		}
 
-
+		if (safe_to_lower || watermarks->b.cstate_pstate.cstate_exit_ns
+				> hubbub->watermarks.b.cstate_pstate.cstate_exit_ns) {
+			hubbub->watermarks.b.cstate_pstate.cstate_exit_ns =
+					watermarks->b.cstate_pstate.cstate_exit_ns;
 			prog_wm_value = convert_and_clamp(
 					watermarks->b.cstate_pstate.cstate_exit_ns,
 					refclk_mhz, 0x1fffff);
@@ -286,43 +318,61 @@ void hubbub1_program_watermarks(
 				"HW register value = 0x%x\n",
 				watermarks->b.cstate_pstate.cstate_exit_ns, prog_wm_value);
 		}
+	}
 
+	if (safe_to_lower || watermarks->b.cstate_pstate.pstate_change_ns
+			> hubbub->watermarks.b.cstate_pstate.pstate_change_ns) {
+		hubbub->watermarks.b.cstate_pstate.pstate_change_ns =
+				watermarks->b.cstate_pstate.pstate_change_ns;
 		prog_wm_value = convert_and_clamp(
 				watermarks->b.cstate_pstate.pstate_change_ns,
 				refclk_mhz, 0x1fffff);
 		REG_WRITE(DCHUBBUB_ARB_ALLOW_DRAM_CLK_CHANGE_WATERMARK_B, prog_wm_value);
-	DC_LOG_BANDWIDTH_CALCS("DRAM_CLK_CHANGE_WATERMARK_B calculated =%d\n\n"
-		"HW register value = 0x%x\n",
+		DC_LOG_BANDWIDTH_CALCS("DRAM_CLK_CHANGE_WATERMARK_B calculated =%d\n"
+			"HW register value = 0x%x\n\n",
 			watermarks->b.cstate_pstate.pstate_change_ns, prog_wm_value);
+	}
 
 	/* clock state C */
-	prog_wm_value = convert_and_clamp(
-			watermarks->c.urgent_ns, refclk_mhz, 0x1fffff);
+	if (safe_to_lower || watermarks->c.urgent_ns > hubbub->watermarks.c.urgent_ns) {
+		hubbub->watermarks.c.urgent_ns = watermarks->c.urgent_ns;
+		prog_wm_value = convert_and_clamp(watermarks->c.urgent_ns,
+				refclk_mhz, 0x1fffff);
 		REG_WRITE(DCHUBBUB_ARB_DATA_URGENCY_WATERMARK_C, prog_wm_value);
+
 		DC_LOG_BANDWIDTH_CALCS("URGENCY_WATERMARK_C calculated =%d\n"
 			"HW register value = 0x%x\n",
 			watermarks->c.urgent_ns, prog_wm_value);
+	}
 
-
-	prog_wm_value = convert_and_clamp(
-			watermarks->c.pte_meta_urgent_ns,
+	if (safe_to_lower || watermarks->c.pte_meta_urgent_ns > hubbub->watermarks.c.pte_meta_urgent_ns) {
+		hubbub->watermarks.c.pte_meta_urgent_ns = watermarks->c.pte_meta_urgent_ns;
+		prog_wm_value = convert_and_clamp(watermarks->c.pte_meta_urgent_ns,
 				refclk_mhz, 0x1fffff);
 		REG_WRITE(DCHUBBUB_ARB_PTE_META_URGENCY_WATERMARK_C, prog_wm_value);
 		DC_LOG_BANDWIDTH_CALCS("PTE_META_URGENCY_WATERMARK_C calculated =%d\n"
 			"HW register value = 0x%x\n",
 			watermarks->c.pte_meta_urgent_ns, prog_wm_value);
-
+	}
 
 	if (REG(DCHUBBUB_ARB_ALLOW_SR_ENTER_WATERMARK_C)) {
+		if (safe_to_lower || watermarks->c.cstate_pstate.cstate_enter_plus_exit_ns
+				> hubbub->watermarks.c.cstate_pstate.cstate_enter_plus_exit_ns) {
+			hubbub->watermarks.c.cstate_pstate.cstate_enter_plus_exit_ns =
+					watermarks->c.cstate_pstate.cstate_enter_plus_exit_ns;
 			prog_wm_value = convert_and_clamp(
 					watermarks->c.cstate_pstate.cstate_enter_plus_exit_ns,
 					refclk_mhz, 0x1fffff);
 			REG_WRITE(DCHUBBUB_ARB_ALLOW_SR_ENTER_WATERMARK_C, prog_wm_value);
-		DC_LOG_BANDWIDTH_CALCS("SR_ENTER_WATERMARK_C calculated =%d\n"
+			DC_LOG_BANDWIDTH_CALCS("SR_ENTER_EXIT_WATERMARK_C calculated =%d\n"
 				"HW register value = 0x%x\n",
 				watermarks->c.cstate_pstate.cstate_enter_plus_exit_ns, prog_wm_value);
+		}
 
-
+		if (safe_to_lower || watermarks->c.cstate_pstate.cstate_exit_ns
+				> hubbub->watermarks.c.cstate_pstate.cstate_exit_ns) {
+			hubbub->watermarks.c.cstate_pstate.cstate_exit_ns =
+					watermarks->c.cstate_pstate.cstate_exit_ns;
 			prog_wm_value = convert_and_clamp(
 					watermarks->c.cstate_pstate.cstate_exit_ns,
 					refclk_mhz, 0x1fffff);
@@ -331,42 +381,61 @@ void hubbub1_program_watermarks(
 				"HW register value = 0x%x\n",
 				watermarks->c.cstate_pstate.cstate_exit_ns, prog_wm_value);
 		}
+	}
 
+	if (safe_to_lower || watermarks->c.cstate_pstate.pstate_change_ns
+			> hubbub->watermarks.c.cstate_pstate.pstate_change_ns) {
+		hubbub->watermarks.c.cstate_pstate.pstate_change_ns =
+				watermarks->c.cstate_pstate.pstate_change_ns;
 		prog_wm_value = convert_and_clamp(
 				watermarks->c.cstate_pstate.pstate_change_ns,
 				refclk_mhz, 0x1fffff);
 		REG_WRITE(DCHUBBUB_ARB_ALLOW_DRAM_CLK_CHANGE_WATERMARK_C, prog_wm_value);
-	DC_LOG_BANDWIDTH_CALCS("DRAM_CLK_CHANGE_WATERMARK_C calculated =%d\n\n"
-		"HW register value = 0x%x\n",
+		DC_LOG_BANDWIDTH_CALCS("DRAM_CLK_CHANGE_WATERMARK_C calculated =%d\n"
+			"HW register value = 0x%x\n\n",
 			watermarks->c.cstate_pstate.pstate_change_ns, prog_wm_value);
+	}
 
 	/* clock state D */
-	prog_wm_value = convert_and_clamp(
-			watermarks->d.urgent_ns, refclk_mhz, 0x1fffff);
+	if (safe_to_lower || watermarks->d.urgent_ns > hubbub->watermarks.d.urgent_ns) {
+		hubbub->watermarks.d.urgent_ns = watermarks->d.urgent_ns;
+		prog_wm_value = convert_and_clamp(watermarks->d.urgent_ns,
+				refclk_mhz, 0x1fffff);
 		REG_WRITE(DCHUBBUB_ARB_DATA_URGENCY_WATERMARK_D, prog_wm_value);
+
 		DC_LOG_BANDWIDTH_CALCS("URGENCY_WATERMARK_D calculated =%d\n"
 			"HW register value = 0x%x\n",
 			watermarks->d.urgent_ns, prog_wm_value);
+	}
 
-	prog_wm_value = convert_and_clamp(
-			watermarks->d.pte_meta_urgent_ns,
+	if (safe_to_lower || watermarks->d.pte_meta_urgent_ns > hubbub->watermarks.d.pte_meta_urgent_ns) {
+		hubbub->watermarks.d.pte_meta_urgent_ns = watermarks->d.pte_meta_urgent_ns;
+		prog_wm_value = convert_and_clamp(watermarks->d.pte_meta_urgent_ns,
 				refclk_mhz, 0x1fffff);
 		REG_WRITE(DCHUBBUB_ARB_PTE_META_URGENCY_WATERMARK_D, prog_wm_value);
 		DC_LOG_BANDWIDTH_CALCS("PTE_META_URGENCY_WATERMARK_D calculated =%d\n"
 			"HW register value = 0x%x\n",
 			watermarks->d.pte_meta_urgent_ns, prog_wm_value);
-
+	}
 
 	if (REG(DCHUBBUB_ARB_ALLOW_SR_ENTER_WATERMARK_D)) {
+		if (safe_to_lower || watermarks->d.cstate_pstate.cstate_enter_plus_exit_ns
+				> hubbub->watermarks.d.cstate_pstate.cstate_enter_plus_exit_ns) {
+			hubbub->watermarks.d.cstate_pstate.cstate_enter_plus_exit_ns =
+					watermarks->d.cstate_pstate.cstate_enter_plus_exit_ns;
 			prog_wm_value = convert_and_clamp(
 					watermarks->d.cstate_pstate.cstate_enter_plus_exit_ns,
 					refclk_mhz, 0x1fffff);
 			REG_WRITE(DCHUBBUB_ARB_ALLOW_SR_ENTER_WATERMARK_D, prog_wm_value);
-		DC_LOG_BANDWIDTH_CALCS("SR_ENTER_WATERMARK_D calculated =%d\n"
+			DC_LOG_BANDWIDTH_CALCS("SR_ENTER_EXIT_WATERMARK_D calculated =%d\n"
 				"HW register value = 0x%x\n",
 				watermarks->d.cstate_pstate.cstate_enter_plus_exit_ns, prog_wm_value);
+		}
 
-
+		if (safe_to_lower || watermarks->d.cstate_pstate.cstate_exit_ns
+				> hubbub->watermarks.d.cstate_pstate.cstate_exit_ns) {
+			hubbub->watermarks.d.cstate_pstate.cstate_exit_ns =
+					watermarks->d.cstate_pstate.cstate_exit_ns;
 			prog_wm_value = convert_and_clamp(
 					watermarks->d.cstate_pstate.cstate_exit_ns,
 					refclk_mhz, 0x1fffff);
@@ -375,8 +444,12 @@ void hubbub1_program_watermarks(
 				"HW register value = 0x%x\n",
 				watermarks->d.cstate_pstate.cstate_exit_ns, prog_wm_value);
 		}
+	}
 
-
+	if (safe_to_lower || watermarks->d.cstate_pstate.pstate_change_ns
+			> hubbub->watermarks.d.cstate_pstate.pstate_change_ns) {
+		hubbub->watermarks.d.cstate_pstate.pstate_change_ns =
+				watermarks->d.cstate_pstate.pstate_change_ns;
 		prog_wm_value = convert_and_clamp(
 				watermarks->d.cstate_pstate.pstate_change_ns,
 				refclk_mhz, 0x1fffff);
@@ -384,6 +457,7 @@ void hubbub1_program_watermarks(
 		DC_LOG_BANDWIDTH_CALCS("DRAM_CLK_CHANGE_WATERMARK_D calculated =%d\n"
 			"HW register value = 0x%x\n\n",
 			watermarks->d.cstate_pstate.pstate_change_ns, prog_wm_value);
+	}
 
 	REG_UPDATE(DCHUBBUB_ARB_WATERMARK_CHANGE_CNTL,
 			DCHUBBUB_ARB_WATERMARK_CHANGE_REQUEST, 1);

drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hubbub.h

@@ -185,6 +185,7 @@ struct hubbub {
 	const struct dcn_hubbub_shift *shifts;
 	const struct dcn_hubbub_mask *masks;
 	unsigned int debug_test_index_pstate;
+	struct dcn_watermark_set watermarks;
 };
 
 void hubbub1_update_dchub(
@@ -197,7 +198,8 @@ bool hubbub1_verify_allow_pstate_change_high(
 void hubbub1_program_watermarks(
 		struct hubbub *hubbub,
 		struct dcn_watermark_set *watermarks,
-		unsigned int refclk_mhz);
+		unsigned int refclk_mhz,
+		bool safe_to_lower);
 
 void hubbub1_toggle_watermark_change_req(
 		struct hubbub *hubbub);

drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c

@@ -2299,7 +2299,7 @@ static void dcn10_apply_ctx_for_surface(
 
 		/* watermark is for all pipes */
 		hubbub1_program_watermarks(dc->res_pool->hubbub,
-				&context->bw.dcn.watermarks, ref_clk_mhz);
+				&context->bw.dcn.watermarks, ref_clk_mhz, true);
 
 		if (dc->debug.sanity_checks) {
 			/* pstate stuck check after watermark update */