CPU Frequencies - 2020.2 English

Enable this feature to permit the CPU cores to switch between different operation clock frequencies.

Required Kernel Configurations

• CPU Frequency scaling
  • [*] CPU Frequency scaling
  • Default CPUFreq governor
    • Userspace
• CPU Power Management
  • [*] CPU Frequency scaling
  • Default CPUFreq governor
    • Userspace
    • <*> Generic DT based cpufreq driver

Example Commands

The following are some commands related to CPU frequency scaling:

• Look up the available CPU speeds:

  cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_cpu_freq

• Select the 'userspace' governor for CPU frequency control:

  echo userspace > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor

• Look up the current CPU speed (same for all cores):

  cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_cpu_freq

• Change the CPU speed (same for all cores):

  echo <freq> > /sys/devices/system/cpu/cpu0/cpufreq/scaling_setspeed

For details on adding and changing CPU frequencies, see the Linux kernel documentation on Generic Operating Points.