> ## Documentation Index
> Fetch the complete documentation index at: https://dragonwingdocs.qualcomm.com/llms.txt
> Use this file to discover all available pages before exploring further.

# ThermalD

<a id="thermalD" />

# 配置 ThermalD

ThermalD 是一个 Linux 守护进程,通过持续监控温度传感器并使用可用的冷却机制应用热缓解,帮助防止平台过热。它作为一个智能热管理系统,在硬件需要采取激进的纠正措施之前,主动维持安全的工作温度。

ThermalD 使用数字温度传感器监控 CPU 和整个系统的温度,并通过采用多种冷却策略来实施热控制,例如:

* CPU 频率调节
* 功率限制
* 风扇控制

该守护进程与 Linux 热管理子系统(`/sys/class/thermal`)集成,并使用基于 XML 的配置文件扩展或覆盖内核热管理策略。它既支持通过 ACPI 热关系表进行自动配置,也支持手动配置以启用自定义热管理策略。

以下是 ThermalD 的 XML 结构概览:

```xml theme={null}
<?xml version="1.0"?>
<ThermalConfiguration>
    <Platform>
    <Name>Platform Name</Name>
    <ProductName>Product Name or *</ProductName>
    <UUID>Optional UUID</UUID>
    <Preference>QUIET|PERFORMANCE</Preference>

    <ThermalSensors>
        <!-- Sensor definitions -->
    </ThermalSensors>

    <ThermalZones>
        <!-- Zone and trip point definitions -->
    </ThermalZones>

    <CoolingDevices>
        <!-- Cooling device configurations -->
    </CoolingDevices>
    </Platform>
</ThermalConfiguration>
```

## 向 ThermalD 推送自定义规则

ThermalD 使用配置文件 `/etc/thermald/thermal-conf.xml` 进行手动配置。

以下示例展示了如何使用 XML 配置文件手动配置 ThermalD 来管理 GPU 和 CPU 热区:

* 该配置指定了三个热传感器,一个用于 GPU,两个用于不同的 CPU 集群,每个传感器都与被动冷却触发点关联。GPU 热区在 35 °C 时触发,而 CPU 集群热区分别在 40 °C 和 45 °C 时激活。

* 所有热区都使用 CPU 或 GPU 频率调节作为冷却机制,采样间隔为 100 ms,并采用 5 °C 的迟滞以防止热振荡。冷却设备配置了定义的状态范围并启用了自动降档控制,从而实现渐进且可控的温度降低。

```xml theme={null}
<ThermalConfiguration>
    <Platform>
        <Name>*</Name>
        <UUID>*</UUID>
        <ProductName>*</ProductName>
        <Preference>QUIET</Preference>
        <!-- 100ms polling interval -->
        <PollingInterval>5</PollingInterval>
        <ThermalSensors>
            <ThermalSensor>
                <Type>gpuss-0-thermal</Type>
                <AsyncCapable>0</AsyncCapable>
            </ThermalSensor>
        </ThermalSensors>
        <ThermalSensors>
            <ThermalSensor>
                <Type>cpu-0-0-0-thermal</Type>
                <AsyncCapable>0</AsyncCapable>
            </ThermalSensor>
        </ThermalSensors>
        <ThermalSensors>
            <ThermalSensor>
                <Type>cpu-1-1-1-thermal</Type>
                <AsyncCapable>0</AsyncCapable>
            </ThermalSensor>
        </ThermalSensors>

        <ThermalZones>
            <ThermalZone>
                <Type>gpuss-0-thermal</Type>
                <TripPoints>
                    <TripPoint>
                        <SensorType>gpuss-0-thermal</SensorType>
                        <Temperature>35000</Temperature>
                        <Hysteresis>5000</Hysteresis>
                        <Hyst>5000</Hyst>
                        <type>passive</type>
                        <ControlType>SEQUENTIAL</ControlType>
                        <CoolingDevice>
                            <index>0</index>
                            <type>devfreq-3d00000.gpu</type>
                            <influence>5000</influence>
                            <SamplingPeriod>5</SamplingPeriod>  <!-- 100ms sampling -->
                        </CoolingDevice>
                    </TripPoint>
                </TripPoints>
            </ThermalZone>
            <ThermalZone>
                <Type>cpu-0-0-0-thermal</Type>
                <TripPoints>
                    <TripPoint>
                        <SensorType>cpu-0-0-0-thermal</SensorType>
                        <Temperature>40000</Temperature>  <!-- 75°C threshold -->
                        <Hysteresis>5000</Hysteresis>
                        <Hyst>5000</Hyst>
                        <type>passive</type>
                        <ControlType>SEQUENTIAL</ControlType>
                        <CoolingDevice>
                            <index>0</index>
                            <type>cpufreq-cpu0</type>
                            <influence>5000</influence>
                            <SamplingPeriod>5</SamplingPeriod>  <!-- 100ms sampling -->
                        </CoolingDevice>
                    </TripPoint>
                </TripPoints>
            </ThermalZone>
            <ThermalZone>
                <Type>cpu-1-1-1-thermal</Type>
                <TripPoints>
                    <TripPoint>
                        <SensorType>cpu-1-1-1-thermal</SensorType>
                        <Temperature>45000</Temperature>  <!-- 75°C threshold -->
                        <Hysteresis>5000</Hysteresis>
                        <Hyst>5000</Hyst>
                        <type>passive</type>
                        <ControlType>SEQUENTIAL</ControlType>
                        <CoolingDevice>
                            <index>0</index>
                            <type>cpufreq-cpu4</type>
                            <influence>5000</influence>
                            <SamplingPeriod>5</SamplingPeriod>  <!-- 100ms sampling -->
                        </CoolingDevice>
                    </TripPoint>
                </TripPoints>
            </ThermalZone>
        </ThermalZones>

        <CoolingDevices>
            <CoolingDevice>
                <Index>0</Index>
                <Type>devfreq-3d00000.gpu</Type>
                <SysfsPath>/sys/class/thermal/cooling_device2</SysfsPath>
                <MinState>0</MinState>
                <MaxState>3</MaxState>
                <IncDecStep>1</IncDecStep>
                <ReadBack>1</ReadBack>
                <AutoDownControl>1</AutoDownControl>
                <TargetState>1</TargetState>
            </CoolingDevice>
            <CoolingDevice>
                <Index>0</Index>
                <Type>cpufreq-cpu0</Type>
                <SysfsPath>/sys/class/thermal/cooling_device0</SysfsPath>
                <MinState>0</MinState>
                <MaxState>13</MaxState>
                <IncDecStep>1</IncDecStep>
                <ReadBack>1</ReadBack>
                <AutoDownControl>1</AutoDownControl>
                <TargetState>1</TargetState>
            </CoolingDevice>
            <CoolingDevice>
                <Index>0</Index>
                <Type>cpufreq-cpu4</Type>
                <SysfsPath>/sys/class/thermal/cooling_device1</SysfsPath>
                <MinState>0</MinState>
                <MaxState>13</MaxState>
                <IncDecStep>1</IncDecStep>
                <ReadBack>1</ReadBack>
                <AutoDownControl>1</AutoDownControl>
                <TargetState>1</TargetState>
            </CoolingDevice>
        </CoolingDevices>
    </Platform>
</ThermalConfiguration>
```

> **注意**
>
> 更多信息请参阅 [Thermal Daemon](https://github.com/intel/thermal_daemon/blob/master/README.txt)。

## 后续步骤

* [验证热状态](./verify-thermal-state)