Current implementation of i.MX8QX 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>
NXP's i.MX8QX is an ARMv8 SoC with 4 Cortex-A35 cores and
system controller (Cortex-M4) inside, documentation can
be found in below link:
https://www.nxp.com/products/processors-and-microcontrollers/
applications-processors/i.mx-applications-processors/i.mx-8-processors:IMX8-SERIES
This patch adds support for booting up SMP linux kernel (v4.9).
Signed-off-by: Anson Huang <Anson.Huang@nxp.com>