AMD EPYC Milan: Wrong CPU frequency

[Mace]

Yesterday I installed a fresh Proxmox node on my new server with an AMD Epyc Milan processor. During first install, I got the following error message:

pve kernel: [Firmware Bug]: ACPI: Invalid BIOS _PSS frequency found for processor 0: 0x0 MHz

This repeated itself for every core (32 in total).

Proxmox installed fine despite this, but does present an issue in daily use. The CPU max frequency is reported as 2200 MHz in lscpu and this is also the maximum frequency that the CPU is running at. As the CPU can do 3700MHz, this is really an issue.

I've tested the server extensively with a bare metal Windows install, and there the CPU worked perfectly on the highest CPU frequency, scaled back, throttle up etc, just how it should work. For me, this rules out a bios setting (unless there is an issue with Proxmox and the ACPI state).

Would like to have advice on how to solve this.

 

[tom]

Try our 5.11 kernel.

 

[Mace]

Thanks, @tom ! That bumped the speed up to 2734MHz, still 1GHz to go.....Shall I report this in the 5.11 kernel thread?

 

[Dunuin]

pve kernel: [Firmware Bug]: ACPI: Invalid BIOS _PSS frequency found for processor 0: 0x0 MHz
I got that bug too and its a Supermicro X10SRM-F mainboard with latest BIOS (from october 2020) and a Xeon E5-2620v4. I'm on kernel 5.4 but that shoudn't be the point when the hardware is 5 years old right?

lscpu | grep MHz is reporting...

CPU MHz:             2363.689
CPU max MHz:         3000.0000
CPU min MHz:         1200.0000

... and watch -n1 "grep \"^[c]pu MHz\" /proc/cpuinfo" shows me cores switching between around 1400 and 2800 MHz so I just ignored it for months because the CPU is rated at 2,10 GHz with boost up to 3,0 GHz what fits with my measurements.

 

[Mace]

driver: acpi-cpufreq CPUs which run at the same hardware frequency: 0 CPUs which need to have their frequency coordinated by software: 0 maximum transition latency: Cannot determine or is not supported. hardware limits: 1.50 GHz - 2.73 GHz available frequency steps: 2.20 GHz, 1.50 GHz available cpufreq governors: conservative ondemand userspace powersave performance schedutil current policy: frequency should be within 1.50 GHz and 2.20 GHz. The governor "ondemand" may decide which speed to use within this range. current CPU frequency: 1.50 GHz (asserted by call to hardware) boost state support: Supported: yes Active: no Boost States: 0 Total States: 3 Pstate-P0: 3600MHz Pstate-P1: 2000MHz Pstate-P2: 2100MHz
So reporting is weird and somehow Boost state IS supported, but not active. Don't know how to activate this. Max frequency stays at 2200MHz.

 

[Dunuin]

I had to allow Boost in BIOS.

 

[Mace]

With the help of Level1Techs Forum and setting the cTDP manully, I now get the correct frequencies. Can be closed.

 

[Dunuin]

I still would like to know what is causing the "pve kernel: [Firmware Bug]: ACPI: Invalid BIOS _PSS frequency found for processor 0: 0x0 MHz" message. Maybe something is going wrong and we just can't see it.

 

[Mace]

Good point @Dunuin . I'm already happy that it works, but the error stays and also the Boost Active is stil on no....

 

[Mace]

Any news on this? Did a total clean reinstall and still the same

 

[VinnyG]

i get this error when setting intel_pstate=active on kernel with HWP > hardware managed on bios, also cpufreq-info shows no driver loaded

no idea why proxmox sets cpufreq driver by default on a broadwell chip instead of intel_pstate

pstate driver seems to work with HWP in software managed mode BUT THEN DMESG reports HWP as disabled which afaik is the same as passive mode / cpufreq

I'm on latest kernel
will try with 6.5 on another board/node