From mboxrd@z Thu Jan  1 00:00:00 1970
From: viresh.kumar@linaro.org (Viresh Kumar)
Date: Wed, 3 Feb 2016 21:44:28 +0530
Subject: Plain DFS (no voltage scaling)
In-Reply-To: <56B21E2E.1070606@free.fr>
References: <56B11B67.3090600@free.fr> <20160203021052.GK31828@vireshk>
 <56B21E2E.1070606@free.fr>
Message-ID: <20160203161428.GJ3469@vireshk>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On 03-02-16, 16:35, Mason wrote:
> On 03/02/2016 03:10, Viresh Kumar wrote:
> > On 02-02-16, 22:11, Mason wrote:
> >> Hello,
> >>
> >> I plan to enable the on-demand governor on the tango platform:
> >> https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/arch/arm/boot/dts/tango4-smp8758.dtsi
> >>
> >> I found the cpufreq-dt binding doc:
> >>
> >> https://www.kernel.org/doc/Documentation/devicetree/bindings/cpufreq/cpufreq-dt.txt
> >> https://www.kernel.org/doc/Documentation/devicetree/bindings/opp/opp.txt
> >>
> >> Something is not clear to me:
> >>
> >> If my platform cannot scale the voltage, what information
> >> should I put in the voltage part of the DT?
> > 
> > Wouldn't matter if there is no regulator. i.e. you should keep 0, but
> > even if they have something non-zero, core code will ignore it. But
> > yeah, it makes sense to keep it zero.
> 
> Hmmm, I am missing something obvious.
> 
> My config contains:
> 
> CONFIG_CPU_FREQ=y
> CONFIG_CPU_FREQ_GOV_COMMON=y
> CONFIG_CPU_FREQ_STAT=y
> CONFIG_CPU_FREQ_STAT_DETAILS=y
> CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE=y
> CONFIG_CPU_FREQ_GOV_PERFORMANCE=y
> CONFIG_CPU_FREQ_GOV_ONDEMAND=y
> CONFIG_CPUFREQ_DT=y
> 
> Yet, neither dt_cpufreq_probe() nor cpufreq_init() are being called.
> 
> Could someone please point to my mistake?

You need to create a platform device to get cpufreq-dt driver probed.
Check other users..

-- 
viresh