ARM: sun8i: a33: add CPU thermal throttling

This adds CPU thermal throttling for the Allwinner A33. It uses the
thermal sensor present in the SoC's GPADC.
Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>

arch/arm/boot/dts/sun8i-a33.dtsi

@@ -43,6 +43,7 @@
  */
 
 #include "sun8i-a23-a33.dtsi"
+#include <dt-bindings/thermal/thermal.h>
 
 / {
 	cpu0_opp_table: opp_table0 {
@@ -133,6 +134,7 @@ cpu@0 {
 			clocks = <&ccu CLK_CPUX>;
 			clock-names = "cpu";
 			operating-points-v2 = <&cpu0_opp_table>;
+			#cooling-cells = <2>;
 		};
 
 		cpu@2 {
@@ -388,6 +390,49 @@ drc0_out_tcon0: endpoint@0 {
 			};
 		};
 	};
+
+	thermal-zones {
+		cpu_thermal {
+			/* milliseconds */
+			polling-delay-passive = <250>;
+			polling-delay = <1000>;
+			thermal-sensors = <&ths>;
+
+			cooling-maps {
+				map0 {
+					trip = <&cpu_alert0>;
+					cooling-device = <&cpu0 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
+				};
+				map1 {
+					trip = <&cpu_alert1>;
+					cooling-device = <&cpu0 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
+				};
+			};
+
+			trips {
+				cpu_alert0: cpu_alert0 {
+					/* milliCelsius */
+					temperature = <75000>;
+					hysteresis = <2000>;
+					type = "passive";
+				};
+
+				cpu_alert1: cpu_alert1 {
+					/* milliCelsius */
+					temperature = <90000>;
+					hysteresis = <2000>;
+					type = "hot";
+				};
+
+				cpu_crit: cpu_crit {
+					/* milliCelsius */
+					temperature = <110000>;
+					hysteresis = <2000>;
+					type = "critical";
+				};
+			};
+		};
+	};
 };
 
 &ccu {