cpufreq: arm_scmi: Set fast_switch_possible conditionally

Currently the fast_switch_possible flag is set unconditionally to true.
Based on this, schedutil does not create a thread for frequency
switching and would always use the fast switch path.

However, if the platform does not support SCMI fast channel, we use
polling mode for SCMI message transfer. This may be possible only if
there is dedicated channel for DVFS and all operations are in polling
mode.

Update this by retrieving the fast_switch capability based on the
presence of fast channels in SCMI platform firmware.

Link: https://lore.kernel.org/r/20200617094332.8391-2-nicola.mazzucato@arm.com
Suggested-by: Lukasz Luba <lukasz.luba@arm.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Nicola Mazzucato <nicola.mazzucato@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
This commit is contained in:
Nicola Mazzucato 2020-06-17 10:43:32 +01:00 committed by Sudeep Holla
parent 1909872ff2
commit fb3571276b

View File

@ -198,7 +198,8 @@ static int scmi_cpufreq_init(struct cpufreq_policy *policy)
policy->cpuinfo.transition_latency = latency;
policy->fast_switch_possible = true;
policy->fast_switch_possible =
handle->perf_ops->fast_switch_possible(handle, cpu_dev);
em_register_perf_domain(policy->cpus, nr_opp, &em_cb);