SYSTEM PM System PM device is a virtual device that handles all CPU subsystem low power mode activties. When entering core shutdown, resource state that were requested from the processor may be relinquished and set to idle and restored when the cores are brought out of sleep. PROPERTIES - compatible: Usage: required Value type: Definition: must be "qcom,system-pm". -mboxes: Usage: optional Value type: Definition: phandle the TCS mailbox controller for the CPU subsystem. This property is generally set only for SoCs that use RPMH communication through a mailbox controller. EXAMPLE system_pm { compatible = "qcom,system-pm"; mboxes = <&apps_rsc 0>; };