AnsweredAssumed Answered

Invalid  cpufreq-info in Linux 4.9.11 kernel verison

Question asked by Gopinath Srinivasan on Mar 26, 2018
Latest reply on Mar 27, 2018 by Gopinath Srinivasan

Hello Everyone,

 

I am evaluating IMX7 sabreSD board in Linux 4.1.15 and Linux 4.9.11 kernel version. When I checked cpufreq-info command in 4.9.11 kernel, it is showing below information. 

 

root@imx6ul7d:~# cpufreq-info
cpufrequtils 008: cpufreq-info (C) Dominik Brodowski 2004-2009
Report errors and bugs to cpufreq@vger.kernel.org, please.
analyzing CPU 0:
driver: imx7d-cpufreq
CPUs which run at the same hardware frequency: 0 1
CPUs which need to have their frequency coordinated by software: 0 1
maximum transition latency: 101 us.
hardware limits: 792 MHz - 1.20 GHz
available frequency steps: 792 MHz, 996 MHz, 1.20 GHz
available cpufreq governors: interactive, conservative, userspace, powersave, ondemand, performance
current policy: frequency should be within 792 MHz and 1.20 GHz.
The governor "ondemand" may decide which speed to use
within this range.
current CPU frequency is 792 MHz (asserted by call to hardware).
cpufreq stats: 792 MHz:71.84%, 996 MHz:11.36%, 1.20 GHz:16.81% (22)
analyzing CPU 1:
driver: imx7d-cpufreq
CPUs which run at the same hardware frequency: 0 1
CPUs which need to have their frequency coordinated by software: 0 1
maximum transition latency: 101 us.
hardware limits: 792 MHz - 1.20 GHz
available frequency steps: 792 MHz, 996 MHz, 1.20 GHz
available cpufreq governors: interactive, conservative, userspace, powersave, ondemand, performance
current policy: frequency should be within 792 MHz and 1.20 GHz.
The governor "ondemand" may decide which speed to use
within this range.
current CPU frequency is 792 MHz (asserted by call to hardware).
cpufreq stats: 792 MHz:71.84%, 996 MHz:11.36%, 1.20 GHz:16.81% (22)

 

Where as in the same device shows different value in 4.1.15 kernel version. 

 

root@imx7dsabresd:~# cpufreq-info
cpufrequtils 008: cpufreq-info (C) Dominik Brodowski 2004-2009
Report errors and bugs to cpufreq@vger.kernel.org, please.
analyzing CPU 0:
driver: imx7d-cpufreq
CPUs which run at the same hardware frequency: 0 1
CPUs which need to have their frequency coordinated by software: 0 1
maximum transition latency: 61.0 us.
hardware limits: 792 MHz - 996 MHz
available frequency steps: 792 MHz, 996 MHz
available cpufreq governors: interactive, conservative, userspace, powersave, ondemand, performance
current policy: frequency should be within 792 MHz and 996 MHz.
The governor "ondemand" may decide which speed to use
within this range.
current CPU frequency is 792 MHz (asserted by call to hardware).
cpufreq stats: 792 MHz:64.26%, 996 MHz:35.74% (18)
analyzing CPU 1:
driver: imx7d-cpufreq
CPUs which run at the same hardware frequency: 0 1
CPUs which need to have their frequency coordinated by software: 0 1
maximum transition latency: 61.0 us.
hardware limits: 792 MHz - 996 MHz
available frequency steps: 792 MHz, 996 MHz
available cpufreq governors: interactive, conservative, userspace, powersave, ondemand, performance
current policy: frequency should be within 792 MHz and 996 MHz.
The governor "ondemand" may decide which speed to use
within this range.
current CPU frequency is 792 MHz (asserted by call to hardware).
cpufreq stats: 792 MHz:64.26%, 996 MHz:35.74% (18)

 

I guess, 4.9.11 kernel is showing invalid CPU frequency rates since as per the part number the processor supports only up to 996MHZ . May I know how to fix this issue in kernel version 4.9.11? May be I need to use different DTS file? or defconfig file?

 

Thanks,

Gopinath S 

Outcomes