ARM: dts: sti: add thermal-zones support on stih418

Add a 'thermal-zones' node for stih418.

A thermal-zone needs three components:
  - thermal sensors, described in an earlier commit[1]
  - cooling devices, specified for each CPU
  - a thermal zone, describing the overall behavior.

The thermal zone needs references to both CPUs and thermal sensors,
which phandle are also added. The thermal management will then be
achieved on CPUs using the cpufreq framework.

[1] https://lore.kernel.org/lkml/[email protected]/

Reviewed-by: Patrice Chotard <[email protected]>
Signed-off-by: Raphael Gallais-Pou <[email protected]>
Signed-off-by: Patrice Chotard <[email protected]>

2 files changed, 42 insertions, 5 deletions

diff --git a/arch/arm/boot/dts/st/stih407-family.dtsi b/arch/arm/boot/dts/st/stih407-family.dtsi
index 29302e74aa1d..35a55aef7f4b 100644
--- a/arch/arm/boot/dts/st/stih407-family.dtsi
+++ b/arch/arm/boot/dts/st/stih407-family.dtsi
@@ -33,7 +33,7 @@
 	cpus {
 		#address-cells = <1>;
 		#size-cells = <0>;
-		cpu@0 {
+		cpu0: cpu@0 {
 			device_type = "cpu";
 			compatible = "arm,cortex-a9";
 			reg = <0>;
@@ -52,8 +52,9 @@
 			clock-latency = <100000>;
 			cpu0-supply = <&pwm_regulator>;
 			st,syscfg = <&syscfg_core 0x8e0>;
+			#cooling-cells = <2>;
 		};
-		cpu@1 {
+		cpu1: cpu@1 {
 			device_type = "cpu";
 			compatible = "arm,cortex-a9";
 			reg = <1>;
@@ -66,6 +67,7 @@
 					    1200000 0
 					    800000  0
 					    500000  0>;
+			#cooling-cells = <2>;
 		};
 	};
 
diff --git a/arch/arm/boot/dts/st/stih418.dtsi b/arch/arm/boot/dts/st/stih418.dtsi
index 0f0db988a907..8fb8b3af5e49 100644
--- a/arch/arm/boot/dts/st/stih418.dtsi
+++ b/arch/arm/boot/dts/st/stih418.dtsi
@@ -6,23 +6,26 @@
 #include "stih418-clock.dtsi"
 #include "stih407-family.dtsi"
 #include "stih410-pinctrl.dtsi"
+#include <dt-bindings/thermal/thermal.h>
 / {
 	cpus {
 		#address-cells = <1>;
 		#size-cells = <0>;
-		cpu@2 {
+		cpu2: cpu@2 {
 			device_type = "cpu";
 			compatible = "arm,cortex-a9";
 			reg = <2>;
 			/* u-boot puts hpen in SBC dmem at 0xa4 offset */
 			cpu-release-addr = <0x94100A4>;
+			#cooling-cells = <2>;
 		};
-		cpu@3 {
+		cpu3: cpu@3 {
 			device_type = "cpu";
 			compatible = "arm,cortex-a9";
 			reg = <3>;
 			/* u-boot puts hpen in SBC dmem at 0xa4 offset */
 			cpu-release-addr = <0x94100A4>;
+			#cooling-cells = <2>;
 		};
 	};
 
@@ -44,6 +47,38 @@
 		reset-names = "global", "port";
 	};
 
+	thermal-zones {
+		cpu_thermal: cpu-thermal {
+			polling-delay-passive = <250>;  /* 250ms */
+			polling-delay = <1000>;         /* 1000ms */
+
+			thermal-sensors = <&thermal>;
+
+			trips {
+				cpu_crit: cpu-crit {
+					temperature = <95000>;  /* 95C */
+					hysteresis = <2000>;
+					type = "critical";
+				};
+				cpu_alert: cpu-alert {
+					temperature = <85000>;  /* 85C */
+					hysteresis = <2000>;
+					type = "passive";
+				};
+			};
+
+			cooling-maps {
+				map {
+					trip = <&cpu_alert>;
+					cooling-device = <&cpu0 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+							 <&cpu1 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+							 <&cpu2 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+							 <&cpu3 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
+				};
+			};
+		};
+	};
+
 	soc {
 		rng11: rng@8a8a000 {
 			status = "disabled";
@@ -107,7 +142,7 @@
 			assigned-clock-rates = <200000000>;
 		};
 
-		thermal@91a0000 {
+		thermal: thermal@91a0000 {
 			compatible = "st,stih407-thermal";
 			reg = <0x91a0000 0x28>;
 			clock-names = "thermal";