From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nishanth Menon Subject: Re: [PATCH] cpufreq: cpufreq-cpu0: Use a sane boot frequency when booting with a mismatched bootloader configuration Date: Tue, 19 Nov 2013 11:43:49 -0600 Message-ID: <528BA355.4040008@ti.com> References: <1384568535-26611-1-git-send-email-nm@ti.com> <20131116134445.GI11014@S2101-09.ap.freescale.net> <528A27F8.3070402@ti.com> <20131118155753.GU11014@S2101-09.ap.freescale.net> <528A4340.3020508@ti.com> <20131119022133.GB18434@S2101-09.ap.freescale.net> <528B72C1.5060006@ti.com> <528B7CE5.5040502@ti.com> <528B884C.7070908@ti.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-pm-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii" To: Viresh Kumar Cc: Shawn Guo , "Rafael J. Wysocki" , "cpufreq@vger.kernel.org" , "linux-pm@vger.kernel.org" , Linux Kernel Mailing List , Carlos Hernandez On 11/19/2013 11:10 AM, Viresh Kumar wrote: > On 19 November 2013 21:18, Nishanth Menon 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.. > Right, the point is that CPUFREQ_GOV_LIMITS wont help in the case when it is within min-max bound.. the first transition will help bring it to a sane value - that I agree. >> 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? we depend on the first transition to take us to a sane configuration - but we cannot predict when and if it will happen. -- Regards, Nishanth Menon