System Controller API in IMX8QM-MEK

[vinothkumars]

Hi All,

I am working on Power Management - IMX8QM MEK board. I have to integrate system controller API to put system low power mode.

I integrated successfully and I got the following response,

M4F and A53, A72 is OFF

                       sc_pm_set_sys_power_mode(ipc_handle, SC_PM_PW_MODE_OFF)

Board Reboot

                        sc_pm_set_sys_power_mode(ipc_handle, SC_PM_PW_MODE_STBY)

No response

                       sc_pm_set_resource_power_mode(ipc_handle, SC_R_A53_0, SC_PM_PW_MODE_OFF)                 

                       sc_pm_set_resource_power_mode(ipc_handle, SC_R_A53_0, SC_PM_PW_MODE_STBY)     

I don't the perfect the perfect API to suspend resume the A53, A72 CPU's

I am following the following reference,

              https://community.nxp.com/docs/DOC-345249 

Will you please provide proper SCU API for control Application Processor in Suspend and Wakeup from MCU.

Thanks & Regards,

VinothS,

[vinothkumars]

Solution here,

IMX8QM-MEK Power Management difference between Linux and Android 

Regards,

VinothS.

[vinothkumars]

Hi,

When I execute I got the error for the API,

err = sc_pm_set_resource_power_mode(ipc_handle, SC_R_A53_0, SC_PM_PW_MODE_OFF)                 

err = sc_pm_set_resource_power_mode(ipc_handle, SC_R_A53_0, SC_PM_PW_MODE_STBY)     

SC_ERR_NOACCESS     

#define SC_ERR_NOACCESS     4U      /*!< Permission error (no access) */

How to resolve the this error?

Thanks & Regards,

VinothS,

[igorpadykov]

Hi VinothS

additional examples can be found in linux sources, one can look at

sect.2.5.1 Low Level Power Management (PM) Linux Manual

in Linux 5.4.3_1.0.0 Documentation

atf sources:

imx\plat - imx-atf - i.MX ARM Trusted firmware 

Best regards
igor
-----------------------------------------------------------------------------------------------------------------------
Note: If this post answers your question, please click the Correct Answer button. Thank you!
-----------------------------------------------------------------------------------------------------------------------

[vinothkumars]

Thank you Igor for the reply.

I am following same API for Suspend the CPU-A35 and CPU-A72. But, I don't know my implementation is not giving any effect.

This is my implementation for power off CPU's from M4 MCU,

RTN_ERR(sc_pm_req_low_power_mode(ipc_handle, SC_R_A53, SC_PM_PW_MODE_OFF));
RTN_ERR(sc_pm_req_low_power_mode(ipc_handle, SC_R_A53_0, SC_PM_PW_MODE_OFF));
RTN_ERR(sc_pm_req_low_power_mode(ipc_handle, SC_R_A53_1, SC_PM_PW_MODE_OFF));
RTN_ERR(sc_pm_req_low_power_mode(ipc_handle, SC_R_A53_2, SC_PM_PW_MODE_OFF));
RTN_ERR(sc_pm_req_low_power_mode(ipc_handle, SC_R_A53_3, SC_PM_PW_MODE_OFF));
RTN_ERR(sc_pm_req_low_power_mode(ipc_handle, SC_R_A53_0, SC_PM_PW_MODE_OFF));
RTN_ERR(sc_pm_req_low_power_mode(ipc_handle, SC_R_A72, SC_PM_PW_MODE_OFF));
RTN_ERR(sc_pm_req_low_power_mode(ipc_handle, SC_R_A72_0, SC_PM_PW_MODE_OFF));
RTN_ERR(sc_pm_req_low_power_mode(ipc_handle, SC_R_A72_1, SC_PM_PW_MODE_OFF));
RTN_ERR(sc_pm_req_cpu_low_power_mode(ipc_handle, SC_R_A53, SC_PM_PW_MODE_OFF, SC_PM_WAKE_SRC_NONE));
RTN_ERR(sc_pm_req_cpu_low_power_mode(ipc_handle, SC_R_A53_0, SC_PM_PW_MODE_OFF, SC_PM_WAKE_SRC_NONE));
RTN_ERR(sc_pm_req_cpu_low_power_mode(ipc_handle, SC_R_A53_1, SC_PM_PW_MODE_OFF, SC_PM_WAKE_SRC_NONE));
RTN_ERR(sc_pm_req_cpu_low_power_mode(ipc_handle, SC_R_A53_2, SC_PM_PW_MODE_OFF, SC_PM_WAKE_SRC_NONE));
RTN_ERR(sc_pm_req_cpu_low_power_mode(ipc_handle, SC_R_A53_3, SC_PM_PW_MODE_OFF, SC_PM_WAKE_SRC_NONE));
RTN_ERR(sc_pm_req_cpu_low_power_mode(ipc_handle, SC_R_A72, SC_PM_PW_MODE_OFF, SC_PM_WAKE_SRC_NONE));

RTN_ERR(sc_pm_req_cpu_low_power_mode(ipc_handle, SC_R_A72_0, SC_PM_PW_MODE_OFF, SC_PM_WAKE_SRC_NONE));

RTN_ERR(sc_pm_req_cpu_low_power_mode(ipc_handle, SC_R_A72_1, SC_PM_PW_MODE_OFF, SC_PM_WAKE_SRC_NONE));

Thanks & Regards,

VinothS,

[igorpadykov]

one can look at imx_pwr_domain_off() in

imx8qm_psci.c\imx8qm\imx\plat - imx-atf - i.MX ARM Trusted firmware 

Best regards
igor

[vinothkumars]

Hi Igor,

from this document,

System Controller Firmware 101 - Power management service 

A cores and GPUs are the only ones with a dedicated external power supplies

So, I unable to handle the power mode of A cores by using SCF API.

Thanks & Regards,

VinothS,

[vinothkumars]

Hi Igor,

Yes I am using the same API (sc_pm_req_low_power_mode, sc_pm_req_cpu_low_power_mode) only.

Thanks & Regards,

VinothS,