arm64: dts: imx8mq: Enable gpu passive throttling

Temperature and hysteresis were picked after the CPU.
Signed-off-by: Guido Günther <agx@sigxcpu.org>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

arch/arm64/boot/dts/freescale/imx8mq.dtsi

@@ -235,12 +235,26 @@ gpu-thermal {
 			thermal-sensors = <&tmu 1>;
 
 			trips {
+				gpu_alert: gpu-alert {
+					temperature = <80000>;
+					hysteresis = <2000>;
+					type = "passive";
+				};
+
 				gpu-crit {
 					temperature = <90000>;
 					hysteresis = <2000>;
 					type = "critical";
 				};
 			};
+
+			cooling-maps {
+				map0 {
+					trip = <&gpu_alert>;
+					cooling-device =
+						<&gpu THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
+				};
+			};
 		};
 
 		vpu-thermal {
@@ -949,6 +963,7 @@ gpu: gpu@38000000 {
 			         <&clk IMX8MQ_CLK_GPU_AXI>,
 			         <&clk IMX8MQ_CLK_GPU_AHB>;
 			clock-names = "core", "shader", "bus", "reg";
+			#cooling-cells = <2>;
 			assigned-clocks = <&clk IMX8MQ_CLK_GPU_CORE_SRC>,
 			                  <&clk IMX8MQ_CLK_GPU_SHADER_SRC>,
 			                  <&clk IMX8MQ_CLK_GPU_AXI>,