From 1c4b2932bd629fe800282114ceb465d3eb5d0737 Mon Sep 17 00:00:00 2001 From: Ulf Hansson Date: Mon, 27 May 2024 16:25:57 +0200 Subject: [PATCH] cpuidle: psci: Enable the hierarchical topology for s2idle on PREEMPT_RT 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 Tested-by: Raghavendra Kakarla # qcm6490 with PREEMPT_RT set Acked-by: Sebastian Andrzej Siewior Link: https://lore.kernel.org/r/20240527142557.321610-8-ulf.hansson@linaro.org --- drivers/cpuidle/cpuidle-psci.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) diff --git a/drivers/cpuidle/cpuidle-psci.c b/drivers/cpuidle/cpuidle-psci.c index ad6ce9fe12b4..2562dc001fc1 100644 --- a/drivers/cpuidle/cpuidle-psci.c +++ b/drivers/cpuidle/cpuidle-psci.c @@ -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; }