power management #34
Description
Power management is tough.
Systems may want to turn off unnecessary components (e.g. parts of graphics system when nothing is plugged into a HDMI port), or suspend. This is frequently managed via power management integrated circuits (PMICs), potentially components getting their own firmware and providing a protocol to the OS, be it via a direct driver or hidden in ACPI methods.
Arm has PSCI for power management: https://www.thegoodpenguin.co.uk/blog/an-overview-of-psci/
RISC-V is defining SBI extensions...