What could be the reason for /sys/devices/system/cpu/cpu0/cpufreq non-existing?
The cpu supports EIST.

My guess is this may not be available because of cpu power/performance settings in the BIOS, but I can’t take down production machines to play with this. Any ideas? The HW is Dell PER 5xx/7xx series.

# cpupower frequency-info analyzing CPU 0:
no or unknown cpufreq driver is active on this CPU
boost state support:
Supported: no
Active: no
2400 MHz max turbo 4 active cores
2400 MHz max turbo 3 active cores
2400 MHz max turbo 2 active cores
2400 MHz max turbo 1 active cores
# ls -l /sys/devices/system/cpu/cpu0/
total 0
drwxr-xr-x 6 root root 0 Feb 20 14:01 cache drwxr-xr-x 7 root root 0 Feb 20 14:01 cpuidle
-r——– 1 root root 4096 Feb 12 17:44 crash_notes lrwxrwxrwx 1 root root 0 Feb 20 14:01 node0 -> ../../node/node0
drwxr-xr-x 2 root root 0 Feb 20 14:01 thermal_throttle drwxr-xr-x 2 root root 0 Feb 20 14:01 topology
# lsmod |grep cpufreq
#