linux-kernel - Re: [Question]: about 'cpuinfo_cur_freq' shown in sysfs when the CPU is in idle state

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Message-ID: <20200603102159.hzctwiqiukwhrpo7@vireshk-i7>
Date:   Wed, 3 Jun 2020 15:51:59 +0530
From:   Viresh Kumar <viresh.kumar@...aro.org>
To:     Sudeep Holla <sudeep.holla@....com>
Cc:     Xiongfeng Wang <wangxiongfeng2@...wei.com>, rjw@...ysocki.net,
        guohanjun@...wei.com, ionela.voinescu@....com,
        linux-pm@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: Re: [Question]: about 'cpuinfo_cur_freq' shown in sysfs when the CPU
 is in idle state

On 03-06-20, 11:17, Sudeep Holla wrote:
> On Wed, Jun 03, 2020 at 03:40:10PM +0530, Viresh Kumar wrote:
> > On 03-06-20, 11:07, Sudeep Holla wrote:
> > > But I have another question. If we can detect that CPPC on some platforms
> > > rely on CPU registers(I assume FFH registers here and not system/io/...
> > > type of GAS registers), can we set dvfs_on_any_cpu(can't recall exact
> > > flag name) to false if not already done to prevent such issues. Or I am
> > > talking non-sense as it may be applicable only for _set operation and
> >
> >           Yes, non-sense :)
> >
> 
> Thanks for confirming 👍.

Hehe.

So, do you agree that we better do the read from the CPUs themselves ?

-- 
viresh