Re: [PATCH 1/8] cpufreq: Auto-register with energy model if asked

From: Lukasz Luba
Date: Tue Aug 10 2021 - 11:34:47 EST




On 8/10/21 10:38 AM, Viresh Kumar wrote:
On 10-08-21, 10:36, Lukasz Luba wrote:
The of_cpufreq_cooling_register() should be called after the EM
is present for the CPU device. When you check that function,
you will see that we call
em_cpu_get(policy->cpu)
to get the EM pointer. Otherwise IPA might fail.

Good point.


In other patch set I had a discussion with Quentin and I've checked
the Performance Domains setup code. There is a code triggering the
rebuilding perf domains with EM from governor. We cannot call
EM registration so late in this cpufreq_online(), not after
cpufreq_init_policy() call.

So this dev_pm_opp_of_unregister_em() must be called before
the policy is initialized. I'm not sure if you still would like
to push forward this patch set in this case.