feat(imx8ulp): add APD power down mode(PD) support in system suspend
The APD can be put into PD mode when linux suspend(mem). This patch
add the support for it. As the whole AP domain's context will be lost,
so we must save the necessary HW module states before entering PD mode,
and we need to restore those contexts when system wake up. Fot details
about which HW module's state will be lost, please refer to the RM.
When APD enter PD mode, only the wakeup event connected to the WUU
can wakeup APD successfully. The upower wakeup source is used to
wakeup APD by RTD due to the factor that the MU between A core & M
core is not connected into WUU to generate wakeup event.
as the SRAM0 will be power down when APD enters PD mode, so we
need to re-init the scmi channels(resides in the SRAM0). otherwise
the SCMI can NOT work anymore.
Signed-off-by: Jacky Bai <ping.bai@nxp.com>
Reviewed-by: Ye Li <ye.li@nxp.com>
Change-Id: I44b0cdc8397e5d6a82081ea6746542e9fa4b9fc1
5 files changed