Lines Matching +full:thermal +full:- +full:sensor
1 # SPDX-License-Identifier: (GPL-2.0)
4 ---
5 $id: http://devicetree.org/schemas/thermal/thermal-zones.yaml#
6 $schema: http://devicetree.org/meta-schemas/base.yaml#
8 title: Thermal zone
11 - Daniel Lezcano <daniel.lezcano@linaro.org>
14 Thermal management is achieved in devicetree by describing the sensor hardware
15 and the software abstraction of cooling devices and thermal zones required to
16 take appropriate action to mitigate thermal overloads.
18 The following node types are used to completely describe a thermal management
20 - thermal-sensor: device that measures temperature, has SoC-specific bindings
21 - cooling-device: device used to dissipate heat either passively or actively
22 - thermal-zones: a container of the following node types used to describe all
23 thermal data for the platform
25 This binding describes the thermal-zones.
27 The polling-delay properties of a thermal-zone are bound to the maximum dT/dt
28 (temperature derivative over time) in two situations for a thermal zone:
29 1. when passive cooling is activated (polling-delay-passive)
30 2. when the zone just needs to be monitored (polling-delay) or when
42 const: thermal-zones
44 A /thermal-zones node is required in order to use the thermal framework to
45 manage input from the various thermal zones in the system in order to
46 mitigate thermal overload conditions. It does not represent a real device
47 in the system, but acts as a container to link a thermal sensor device,
48 platform-data regarding temperature thresholds and the mitigation actions
52 "^[a-zA-Z][a-zA-Z0-9\\-]{1,12}-thermal$":
55 Each thermal zone node contains information about how frequently it
56 must be checked, the sensor responsible for reporting temperature for
57 this zone, one sub-node containing the various trip points for this
58 zone and one sub-node containing all the zone cooling-maps.
61 polling-delay:
65 checking this thermal zone. Setting this to 0 disables the polling
66 timers setup by the thermal framework and assumes that the thermal
69 polling-delay-passive:
73 checking this thermal zone while doing passive cooling. Setting
74 this to 0 disables the polling timers setup by the thermal
75 framework and assumes that the thermal sensors in this zone
78 critical-action:
85 Choose 'reboot' with care, as the hardware may be in thermal stress,
88 over the thermal control.
91 - shutdown
92 - reboot
94 thermal-sensors:
95 $ref: /schemas/types.yaml#/definitions/phandle-array
98 The thermal sensor phandle and sensor specifier used to monitor this
99 thermal zone.
102 $ref: /schemas/types.yaml#/definitions/uint32-array
105 that binds all the sensors listed in this thermal zone.
108 z = c0 * x0 + c1 * x1 + ... + c(n-1) * x(n-1) + cn
113 sensor ID. Additional coefficients are interpreted as constant offset.
115 sustainable-power:
118 An estimate of the sustainable power (in mW) that this thermal zone
120 sustainable power of a 4-inch phone is typically 2000mW, while on a
121 10-inch tablet is around 4500mW.
127 which the thermal framework needs to take action. The actions to
128 be taken are defined in another node called cooling-maps.
131 "^[a-zA-Z][a-zA-Z0-9\\-_]{0,63}$":
137 minimum: -273000
149 (trip temperature - hysteresis). This potentially prevents a
156 - active # enable active cooling e.g. fans
157 - passive # enable passive cooling e.g. throttling cpu
158 - hot # send notification to driver
159 - critical # send notification to driver, trigger shutdown
171 the thermal driver (if a .notify callback is registered).
181 - temperature
182 - hysteresis
183 - type
188 cooling-maps:
192 This node describes the action to be taken when a thermal zone
198 "^map[-a-zA-Z0-9]*$":
205 A phandle of a trip point node within this thermal zone.
207 cooling-device:
208 $ref: /schemas/types.yaml#/definitions/phandle-array
212 device. Using the THERMAL_NO_LIMIT (-1UL) constant in the
213 cooling-device phandle limit specifier lets the framework
220 The cooling contribution to the thermal zone of the referred
223 thermal zone.
226 - trip
227 - cooling-device
231 - polling-delay
232 - polling-delay-passive
233 - thermal-sensors
234 - trips
241 - |
242 #include <dt-bindings/interrupt-controller/arm-gic.h>
243 #include <dt-bindings/thermal/thermal.h>
247 #address-cells = <2>;
248 #size-cells = <2>;
252 tsens0: thermal-sensor@c263000 {
253 compatible = "qcom,sdm845-tsens", "qcom,tsens-v2";
259 interrupt-names = "uplow", "critical";
260 #thermal-sensor-cells = <1>;
263 tsens1: thermal-sensor@c265000 {
264 compatible = "qcom,sdm845-tsens", "qcom,tsens-v2";
270 interrupt-names = "uplow", "critical";
271 #thermal-sensor-cells = <1>;
277 thermal-zones {
278 cpu0-thermal {
279 polling-delay-passive = <250>;
280 polling-delay = <1000>;
282 thermal-sensors = <&tsens0 1>;
285 cpu0_alert0: trip-point0 {
291 cpu0_alert1: trip-point1 {
304 cooling-maps {
308 cooling-device = <&CPU0 3 3>, <&CPU1 3 3>,
315 cooling-device = <&CPU0 5 5>, <&CPU1 5 5>,
323 cluster0-thermal {
324 polling-delay-passive = <250>;
325 polling-delay = <1000>;
327 thermal-sensors = <&tsens0 5>;
330 cluster0_alert0: trip-point0 {
345 gpu-top-thermal {
346 polling-delay-passive = <250>;
347 polling-delay = <1000>;
349 thermal-sensors = <&tsens0 11>;
352 gpu1_alert0: trip-point0 {