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Subject: Re: [PATCH v3 5/7] cpufreq: add function to get the hardware max
 frequency
To:     Ionela Voinescu <ionela.voinescu@arm.com>
Cc:     catalin.marinas@arm.com, will@kernel.org, mark.rutland@arm.com,
        maz@kernel.org, suzuki.poulose@arm.com, sudeep.holla@arm.com,
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        mingo@redhat.com, vincent.guittot@linaro.org,
        viresh.kumar@linaro.org, linux-arm-kernel@lists.infradead.org,
        linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-pm@vger.kernel.org
References: <20200211184542.29585-1-ionela.voinescu@arm.com>
 <20200211184542.29585-6-ionela.voinescu@arm.com>
 <b63a4a47-99e5-9c71-73be-740aedde4714@arm.com>
 <20200213125918.GA2397@arm.com>
From:   Valentin Schneider <valentin.schneider@arm.com>
Message-ID: <cf821516-e66b-94d4-ee63-5f94602a7cff@arm.com>
Date:   Thu, 13 Feb 2020 15:22:11 +0000
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On 2/13/20 12:59 PM, Ionela Voinescu wrote:
>> What about intel_pstate / turbo stuff? IIRC one of Giovanni's issues was that
>> turbo freq is not always reported as the max freq. Dunno if we can do
>> anything about it; at the very least maybe document the caveat?
>>
> 
> Okay, I can add details in the description in regards to potential
> reasons to overwrite this function. But basically this is one of the
> reasons for making this a weak function. The best information we can
> generically get for maximum hardware frequency is cpuinfo.max_freq.
> But if platforms have the possibility to obtain this differently from
> either hardware or firmware they can overwrite this.
> 

Right, that would be handled by a different implementation of
that function, so this wasn't too relevant of a comment. Sorry!