Commit 2af8d585 authored by Dmitry Osipenko's avatar Dmitry Osipenko Committed by Thierry Reding
Browse files

ARM: tegra: nexus7: Improve thermal zones 



Use skin temperature for maintaining temperature that is suitable
specifically for Nexus 7. Add CPU thermal zone that protects silicon.
All these changes don't make a significant difference, but it is a
more correct definition of thermal zones.

Signed-off-by: default avatarDmitry Osipenko <digetx@gmail.com>
Signed-off-by: default avatarThierry Reding <treding@nvidia.com>
parent 3f9c8c11

arch/arm/boot/dts/tegra30-asus-nexus7-grouper-common.dtsi

+52 −4
Original line number Diff line number Diff line
@@ -1255,21 +1255,34 @@ 
	};



	thermal-zones {

		cpu-thermal {

		/*

		 * NCT72 has two sensors:

		 *

		 *	0: internal that monitors ambient/skin temperature

		 *	1: external that is connected to the CPU's diode

		 *

		 * Ideally we should use userspace thermal governor,

		 * but it's a much more complex solution.  The "skin"

		 * zone is a simpler solution which prevents Nexus 7

		 * from getting too hot from a user's tactile perspective.

		 * The CPU zone is intended to protect silicon from damage.

		 */



		skin-thermal {

			polling-delay-passive = <1000>; /* milliseconds */

			polling-delay = <5000>; /* milliseconds */



			thermal-sensors = <&nct72 1>;

			thermal-sensors = <&nct72 0>;



			trips {

				trip0: cpu-alert0 {

				trip0: skin-alert {

					/* throttle at 57C until temperature drops to 56.8C */

					temperature = <57000>;

					hysteresis = <200>;

					type = "passive";

				};



				trip1: cpu-crit {

				trip1: skin-crit {

					/* shut down at 65C */

					temperature = <65000>;

					hysteresis = <2000>;
@@ -1289,5 +1302,40 @@ 
				};

			};

		};



		cpu-thermal {

			polling-delay-passive = <1000>; /* milliseconds */

			polling-delay = <5000>; /* milliseconds */



			thermal-sensors = <&nct72 1>;



			trips {

				trip2: cpu-alert {

					/* throttle at 85C until temperature drops to 84.8C */

					temperature = <85000>;

					hysteresis = <200>;

					type = "passive";

				};



				trip3: cpu-crit {

					/* shut down at 90C */

					temperature = <90000>;

					hysteresis = <2000>;

					type = "critical";

				};

			};



			cooling-maps {

				map1 {

					trip = <&trip2>;

					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>,

							 <&actmon THERMAL_NO_LIMIT

								  THERMAL_NO_LIMIT>;

				};

			};

		};

	};

};