[PATCH v2 2/2] Documentation: devicetree: Add boost-frequency binding to list boost mode frequency
Sudeep.Holla at arm.com
Mon Feb 10 05:51:51 EST 2014
On 10/02/14 07:38, Lukasz Majewski wrote:
> Hi Thomas, Sudeep,
>> On Fri, Feb 7, 2014 at 11:32 PM, Sudeep Holla <Sudeep.Holla at arm.com>
>>> On 07/02/14 17:37, Nishanth Menon wrote:
>>>> On Fri, Feb 7, 2014 at 11:31 AM, Sudeep Holla
>>>> <Sudeep.Holla at arm.com> wrote:
>>>>> Yes I think its counter-intuitive as it's visible to the
>>>>> userspace(list of frequencies and the boost parameters are
>>>>> exposed through sysfs)
>>>> That will be a different problem -> as currently every single
>>>> frequency in the cpufreq list has ability to be marked as boost
>>>> frequency - if userspace does not maintain that, then, IMHO, fix
>>>> the userspace :D
>>> gives the list of frequencies based on the state of the boost
>>> feature at anytime.
>> The list of frequencies in
>> does not change based in the state of the boost feature (enabled or
>> disabled). But the scaling_max_frequency and scaling_min_frequency are
>> updated based on the set of available + boost frequencies available.
> With boost intended behavior is as follow:
> /sys/devices/system/cpu/cpu*/cpufreq/scaling_available_frequencies 
> shows the non boost frequencies no matter if boost is enabled or not.
> Those are the "normal" frequencies.
> When boost is supported (by enabling the CONFIG_CPU_FREQ_BOOST_SW)
> extra sysfs attribute shows up:
> /sys/devices/system/cpu/cpu0/cpufreq/scaling_boost_frequencies 
> in which are listed only the boost frequencies.
Correct, sorry I misunderstood this to dynamic change in
scaling_available_frequencies based on state of boot.
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