Re: Disabling power management firmware decisions

[Daniel Lezcano <daniel.lezcano@linaro.org>]

On 03/19/2015 03:08 PM, Rafael J. Wysocki wrote:
> On Thursday, March 19, 2015 02:33:34 PM Daniel Lezcano wrote:
>>
>> Hi,
>>
>> I would like to do some experiments with the x86 platform but I am
>> facing one big issue.
>>
>> When I use the rapl register to measure the energy consumption with
>> turbostat and another tool written by me. I see no differences between
>> my kernel changes while using the idlestat tool, I see big differences
>> in the idle state durations with the traces.
>>
>> I remember on x86 the firmware overrides all kernel decisions to do the
>> power management. So I assume, it is possible my changes are not
>> measurable because of that.
>>
>> Is there a way to tell the firmware to stop overriding the kernel
>> decisions in order to let the kernel handle idle/dvfs on its own ?
>
> The short answer to that is no, there isn't.  It also may not be firmware,
> but hardware.

mmrfh, that's not funny :(

Thanks for the answer.

   -- Daniel

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