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cpuidle: psci: Enable the hierarchical topology for s2idle on PREEMPT_RT

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To enable the domain-idle-states to be used during s2idle on a PREEMPT_RT
based configuration, let's allow the re-assignment of the ->enter_s2idle()
callback to psci_enter_s2idle_domain_idle_state().

Similar to s2ram, let's leave the support for CPU hotplug outside
PREEMPT_RT, as it's depending on using runtime PM. For s2idle, this means
that an offline CPU's PM domain will remain powered-on. In practise this
may lead to that a shallower idle-state than necessary gets selected, which
shouldn't be an issue (besides wasting power).

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Raghavendra Kakarla <quic_rkakarla@quicinc.com>  # qcm6490 with PREEMPT_RT set
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: https://lore.kernel.org/r/20240527142557.321610-8-ulf.hansson@linaro.org
This commit is contained in:
Ulf Hansson 2024-05-27 16:25:57 +02:00
parent 4517b1c383
commit 1c4b2932bd
1 changed files with 6 additions and 7 deletions
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13
drivers/cpuidle/cpuidle-psci.c
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@ -233,18 +233,17 @@ static int psci_dt_cpu_init_topology(struct cpuidle_driver *drv,
psci_cpuidle_use_syscore = true;
/* The hierarchical topology is limited to s2ram on PREEMPT_RT. */
if (IS_ENABLED(CONFIG_PREEMPT_RT))
return 0;
/*
* Using the deepest state for the CPU to trigger a potential selection
* of a shared state for the domain, assumes the domain states are all
* deeper states.
* deeper states. On PREEMPT_RT the hierarchical topology is limited to
* s2ram and s2idle.
*/
drv->states[state_count - 1].enter = psci_enter_domain_idle_state;
drv->states[state_count - 1].enter_s2idle = psci_enter_s2idle_domain_idle_state;
psci_cpuidle_use_cpuhp = true;
if (!IS_ENABLED(CONFIG_PREEMPT_RT)) {
drv->states[state_count - 1].enter = psci_enter_domain_idle_state;
psci_cpuidle_use_cpuhp = true;
}
return 0;
}