From mboxrd@z Thu Jan 1 00:00:00 1970 From: Viresh Kumar Subject: Re: about system time incorrect after changing cpu frequency Date: Tue, 1 Sep 2015 11:32:36 +0530 Message-ID: <20150901060236.GB1456@linux> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: Sender: cpufreq-owner@vger.kernel.org To: vichy Cc: "cpufreq@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , Linux PM list List-Id: linux-pm@vger.kernel.org On 01-09-15, 13:36, vichy wrote: > >> I try to call below 2 functions to change the frequency of clocksource > >> and clockevent, but the above b) sleep time is still incorrect when > >> cpu runs in 500Mhz. > >> clockevents_update_freq(this_cpu_ptr(gt_evt), gt_clk_rate); > >> __clocksource_updatefreq_hz(>_clocksource, gt_clk_rate); How and when were you calling them? What kernel version is it ? > Clock Event Device: arm_global_timer This driver doesn't have support to update clkevt device's freq. You may need to modify that based on how arch/arm/kernel/smp_twd.c is updated. look for: clockevents_update_freq(). -- viresh From mboxrd@z Thu Jan 1 00:00:00 1970 From: viresh.kumar@linaro.org (Viresh Kumar) Date: Tue, 1 Sep 2015 11:32:36 +0530 Subject: about system time incorrect after changing cpu frequency In-Reply-To: References: Message-ID: <20150901060236.GB1456@linux> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 01-09-15, 13:36, vichy wrote: > >> I try to call below 2 functions to change the frequency of clocksource > >> and clockevent, but the above b) sleep time is still incorrect when > >> cpu runs in 500Mhz. > >> clockevents_update_freq(this_cpu_ptr(gt_evt), gt_clk_rate); > >> __clocksource_updatefreq_hz(>_clocksource, gt_clk_rate); How and when were you calling them? What kernel version is it ? > Clock Event Device: arm_global_timer This driver doesn't have support to update clkevt device's freq. You may need to modify that based on how arch/arm/kernel/smp_twd.c is updated. look for: clockevents_update_freq(). -- viresh