# 动态电压及频率调节

动态电压和频率调节 (DVFS) 是一种用于降低 CPU 在工作期间功耗的技术。该技术可根据负载要求切换 CPU 核频率。DVFS 有助于平衡设备的功耗、性能和温控行为。

![../../_images/Dynamic_voltage.png](data:image/png;base64,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)

**图：DVFS 工作流**

有关 DVFS 的更多信息，请参见 [index: kernel/git/torvalds/linux.git](https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/cpu-freq?h=v6.6)。

例如，如果可用的 CPU 频率为 1 GHz、1.5 GHz 和 2 GHz，而应用必须在 1 GHz 下运行，则 CPU 的最高频率应为 1 GHz。该机制通过确保适当使用 CPU 频率和电压来优化 CPU 功耗，从而支持高性能运行。

## 定制 CPU 频率可调参数

下表列出了用于调试 CPU 频率以平衡功耗和性能的命令：

表：用于调试 CPU 频率的命令

| 命令 | 说明 |
| --- | --- |
| cat /sys/devices/system/cpu/cpufreq/policy<x>/scaling_cur_freq<br>    Copy to clipboard | 读取现有 CPU 频率 |
| cat /sys/devices/system/cpu/cpufreq/policy<x>/scaling_available_frequencies<br>    Copy to clipboard | 读取支持的频率 |
| cat /sys/devices/system/cpu/cpufreq/policy<x>/scaling_min_freq<br>    Copy to clipboard | 读取支持的 CPU 最低频率 |
| echo <cpu freq in KHz> > /sys/devices/system/cpu/cpufreq/policy<x>/scaling_min_freq<br>    Copy to clipboard | <ul class="simple"><br><li><p>设置 CPU 最低频率</p></li><br><li><p>覆盖现有的 CPU 最低频率</p></li><br><li><p>从 <code class="docutils literal notranslate"><span class="pre">scaling_available_frequencies</span></code> 设置任意频率</p></li><br></ul> |
| cat /sys/devices/system/cpu/cpufreq/policy<x>/scaling_max_freq<br>    Copy to clipboard | 读取支持的最大 CPU 频率 |
| echo <cpu freq in KHz> > /sys/devices/system/cpu/cpufreq/policy<x>/scaling_max_freq<br>    Copy to clipboard | <ul class="simple"><br><li><p>设置支持的最大 CPU 频率</p></li><br><li><p>覆盖现有的最大 CPU 频率</p></li><br><li><p>从 <code class="docutils literal notranslate"><span class="pre">scaling_available_frequencies</span></code> 设置任意频率</p></li><br></ul> |

Tab QCS6490/QCS5430
Tab QCS9075
Tab QCS8275

Note

`<x>` 指 0、4、7。

- 0 表示小核群集
- 4 表示大核群集
- 7 表示超大核群集
- 频率单位为 KHz

Note

`<x>` 指 0、4。

- 0 表示 Cluster0
- 4 表示 Cluster1
- 频率单位为 KHz

Note

`<x>` 指 0、2、4。

- 0 表示大核群集
- 2 表示超大核群集
- 4 表示小核群集
- 频率单位为 KHz

通过 `SSH` 命令进行的任何修改都会在设备复位时恢复为默认值。

Last Published: Oct 23, 2025

[Previous Topic
CPU 电源管理](https://docs.qualcomm.com/bundle/publicresource/80-70018-30SC/topics/cpupowermanagement.md) [Next Topic
高效的 CPU 空闲功耗管理](https://docs.qualcomm.com/bundle/publicresource/80-70018-30SC/topics/idlepowermanagement.md)