tree ff6ffd2cc25b596716eb90d0c16efcc7e484943e
parent 19493d98483d236b007ad6b072230cc5d6ab2b63
author Anson Huang <Anson.Huang@nxp.com> 1548317392 +0800
committer Anson Huang <Anson.Huang@nxp.com> 1548725201 +0800

imx: power optimization for i.mx8qm

Current implementation of i.MX8QM power management related
features does NOT optimize power number, all system resources
like CCI, DDR, and A cluster etc. are kept in STBY mode (powered
ON) when system suspend or CPU hotplug.

To lower the power number, OFF mode should be adopted for those
system resources whenever they can be OFF, A cluster will be OFF
if the CPUs in the cluster are all off line, DDR/MU/DB can be OFF
if system suspend, IRQ steer can be OFF if the wakeup source is
belonged to system controller partition, so wakeup source runtime
check is used to determine if IRQ steer can be OFF before system
suspend.

If resources are powered off for suspend, they should be restored
properly after system resume.

Signed-off-by: Anson Huang <Anson.Huang@nxp.com>