CPU Frequency Control with 5.10 or 5.13 on Dragonboard820c

Products Support DragonBoard 820c
#1

Hi. How can I control the cpu frequency with 5.10 or 5.13 Debian release? Neither version seems to have this working:

root@linaro-alip:/sys/devices/system/cpu/cpu0# cpufreq-info
cpufrequtils 008: cpufreq-info (C) Dominik Brodowski 2004-2009
Report errors and bugs to cpufreq@vger.kernel.org, please.
analyzing CPU 0:
no or unknown cpufreq driver is active on this CPU
maximum transition latency: 4294.55 ms.
analyzing CPU 1:
no or unknown cpufreq driver is active on this CPU
maximum transition latency: 4294.55 ms.
analyzing CPU 2:
no or unknown cpufreq driver is active on this CPU
maximum transition latency: 4294.55 ms.
analyzing CPU 3:
no or unknown cpufreq driver is active on this CPU
maximum transition latency: 4294.55 ms.
root@linaro-alip:/sys/devices/system/cpu/cpu0# uname -a
Linux linaro-alip 5.13.0-qcomlt-arm64 #208 SMP PREEMPT Wed Sep 29 00:09:03 UTC 2021 aarch64 GNU/Linux
root@linaro-alip:/sys/devices/system/cpu/cpu0#

thanks,
Kim

#2

I was able to get the cpu frequency control working in 5.13 by modifying the device tree sources. I copied the device tree cpu frequency changes from 5.7 kernel to 5.13. I am assuming the same would work for getting 5.10 kernel cpu frequency control working.

#3

In order to wrap up this thread nicely, it would be nice if you would include the changes you made so that others could learn from it.