RE: [PATCH v7 08/13] cpufreq: amd-pstate: add frequency dynamic boost sysfs control

From: Yuan, Perry
Date: Mon Dec 19 2022 - 01:56:23 EST


[AMD Official Use Only - General]

Hi Thomas

> -----Original Message-----
> From: Thomas Koch <linrunner@xxxxxxx>
> Sent: Sunday, December 18, 2022 8:17 PM
> To: Yuan, Perry <Perry.Yuan@xxxxxxx>
> Cc: Deucher, Alexander <Alexander.Deucher@xxxxxxx>; Sharma, Deepak
> <Deepak.Sharma@xxxxxxx>; Meng, Li (Jassmine) <Li.Meng@xxxxxxx>;
> Limonciello, Mario <Mario.Limonciello@xxxxxxx>; Fontenot, Nathan
> <Nathan.Fontenot@xxxxxxx>; Huang, Shimmer
> <Shimmer.Huang@xxxxxxx>; Du, Xiaojian <Xiaojian.Du@xxxxxxx>; linux-
> kernel@xxxxxxxxxxxxxxx; linux-pm@xxxxxxxxxxxxxxx;
> rafael.j.wysocki@xxxxxxxxx; Huang, Ray <Ray.Huang@xxxxxxx>;
> viresh.kumar@xxxxxxxxxx; Karny, Wyes <Wyes.Karny@xxxxxxx>
> Subject: Re: [PATCH v7 08/13] cpufreq: amd-pstate: add frequency dynamic
> boost sysfs control
>
> Hi Perry,
>
> in amd_pstate active mode, where is the equivalent to
> /sys/devices/system/cpu/cpufreq/boost?
>
> Is it /sys/devices/system/cpu/amd-pstate/cppc_dynamic_boost or
> something else?
>
> --
> Freundliche Grüße / Kind regards,
> Thomas Koch

In the EPP driver mode, there is no frequency boost options to control for user end currently, the boost is created for the iowait boost feature.
The CPU cores scaling range is controlled by the lowlevel firmware.
Next, we will consider adding interface to influence the Min/Max Frequency if customers need that.

Perry.

>
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