PSCI CPU idle Driver

modulename: cpuidle-psci.ko

configname: CONFIG_ARM_PSCI_CPUIDLE

Linux Kernel Configuration
└─>Power management and ACPI options
└─>CPU Idle
└─>ARM CPU Idle Drivers
└─>PSCI CPU idle Driver
In linux kernel since version 5.1 (release Date: 2019-05-05)  
Select this to enable PSCI firmware based CPUidle driver for ARM.
It provides an idle driver that is capable of detecting and
managing idle states through the PSCI firmware interface.

The driver has limitations when used with PREEMPT_RT:
- If the idle states are described with the non-hierarchical layout,
all idle states are still available.

- If the idle states are described with the hierarchical layout,
only the idle states defined per CPU are available, but not the ones
being shared among a group of CPUs (aka cluster idle states).

source code: