On 14 May 2015 at 19:29, Viresh Kumar <viresh.kumar@xxxxxxxxxx> wrote: > On 14 May 2015 at 18:36, Mason <slash.tmp@xxxxxxx> wrote: >> When I execute "echo 18500 > scaling_max_freq" >> the system is supposed to change the CPU frequency to 18.5 MHz >> (I might have a bug lurking there) and PERIPHCLK is 1/2 of that, >> i.e 9.25 MHz. > > So at least we are on the right path. But it looks to me that this > call is not getting propagated well. > > From the attachment you gave initially, the event handler for > twd-timers is: tick_handle_periodic(). i.e. you are running in > periodic mode and not onshot... > > why ? > >> Yes, I do, but I was trying to use as much generic code as >> possible to limit the chances of introducing bugs. > > Hmm.. > >> I'll take a fresh look at the ARM GLOBAL TIMER, but last I >> checked, it didn't seem to handle frequency scaling. > > why is that required? Why will you change its freq ? > The same timer is probably used for SPEAr (the platform > I used to work on): > > http://lxr.free-electrons.com/source/arch/arm/mach-spear/time.c?v=3.14 And this might be the problem you are facing: http://lists.infradead.org/pipermail/linux-arm-kernel/2012-May/098564.html -- To unsubscribe from this list: send the line "unsubscribe cpufreq" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
