Re: Unable to disable AMD cpu boost using amd-pstate driver?

[Huang Rui <ray.huang@amd.com>]

On Sun, Sep 17, 2023 at 05:52:06PM +0800, Qu Wenruo wrote:
> Hi Rui,
> 
> Thanks for your hard work maintaining amd-pstate driver first.
> 
> However it looks like if amd-pstate is used, there is no way to properly
> disable the CPU boost (this becomes obvious especially in Linux 6.5, as
> amd-pstate is enabled for my 7940HS CPU by default).
> 
> Previously using acpi-cppc, there is always a file named "boost" in
> /sys/devices/system/cpu/cpufreq, and echo 0 into that file makes my CPU
> temp never cross 75 during gaming sessions.
> 
> 
> But in Linux 6.5, with amd-pstate, I have to go amd_state=passive to get
> that file back, and echoing 0 into that file makes no difference.
> I still easily got 90C during the same game.

Have you tried amd_state=active and set balance_power? We can support EPP
and the EPP_INDEX_BALANCE_POWERSAVE maybe fit for your case.

Thanks,
Ray

> 
> For now I have to completely disable amd-pstate and rollback to acpi
> driver to get a sane temperature.
> 
> Is there any proper way to disable the boost using amd-pstate?
> 
> Thanks,
> Qu