On Mon, Feb 1, 2021 at 11:06 AM Viresh Kumar <viresh.kumar@xxxxxxxxxx> wrote: > > On 01-02-21, 10:44, Dominik Brodowski wrote: > > IIRC, it was required on various ARM systems,[*] as CPUs were registered as > > subsys_initcall(), while cpufreq used to be initialized only later, as an > > s/later/earlier ? arch happens before subsys not at least and that is > the only way we can break cpufreq here, i.e. when the driver comes up > before the CPUs are registered. > > > arch_initcall(). If the ordering is opposite now on all architectures (it > > wasn't on ARM back then), we should be fine. > > > > [*] https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git/commit/arch/arm/mach-sa1100/cpu-sa1100.c?id=f59d3bbe35f6268d729f51be82af8325d62f20f5 > > Thanks for your reply, it made me look at that aspect in some more > detail to confirm I don't end up breaking anything. Unless I am making > a mistake in reading the code, this is the code flow that we have > right now: > > start_kernel() > -> kernel_init() > -> kernel_init_freeable() > -> do_basic_setup() > -> driver_init() > -> cpu_dev_init() > -> subsys_system_register(for-CPUs) > > -> do_initcalls() > -> register-cpufreq-driver from any level > > And so CPUs should always be there for a cpufreq driver. > > Makes sense ? It does to me, but can you update the changelog, please?
