linux-kernel - Re: [PATCH] cpufreq: cpufreq-cpu0: Use a sane boot frequency when booting with a mismatched bootloader configuration

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Message-ID: <CAKohpo=brpnLe68ExPRPg9h5ABMhg+GS85Ebn-+S5-vWaStrPQ@mail.gmail.com>
Date:	Tue, 19 Nov 2013 22:40:29 +0530
From:	Viresh Kumar <viresh.kumar@...aro.org>
To:	Nishanth Menon <nm@...com>
Cc:	Shawn Guo <shawn.guo@...aro.org>,
	"Rafael J. Wysocki" <rjw@...ysocki.net>,
	"cpufreq@...r.kernel.org" <cpufreq@...r.kernel.org>,
	"linux-pm@...r.kernel.org" <linux-pm@...r.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Carlos Hernandez <ceh@...com>
Subject: Re: [PATCH] cpufreq: cpufreq-cpu0: Use a sane boot frequency when
 booting with a mismatched bootloader configuration

On 19 November 2013 21:18, Nishanth Menon <nm@...com> wrote:
> is that true for userspace governor
> (CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE)?
> /sys/devices/system/cpu/cpu0/cpufreq $ cat scaling_available_frequencies
> 500000 1000000 1500000
>
> /sys/devices/system/cpu/cpu0/cpufreq $ cat scaling_cur_freq
> 1100000

No, but userspace governor must take care of this stuff as it want's
to change freq from userspace..

> OMAP5-UEVM will remain at this frequency for a long period of time
> with AVS voltage(Adaptive Voltage Scaling technique used in OMAP to
> optimize operational voltage) that was meant for 1GHz! that is
> definitely not stable if there is no further transition to a valid
> frequency.

I understand that point, but will this stay for a long time at that freq?
Why aren't governors coming into picture here?

> An alternative might be to ensure CPUFREQ_GOV_LIMITS takes care of that?

Again, I don't see if we really really need to do this at all..
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