[imx8dxl] wake up A35 from GPIO in SCU

[hojames2025]

Hello,

We are using imx8dxl.

Our requirement is,

wake up the A35 core from some GPIO pin in SCU-FW (or in the None-secure OS which communicates with SCU).

(For some reasons, we are not using the ON_OFF button)

Currently, for test purpose, I put the code in board_monitor_custom() of

imx-scfw-porting-kit-1.18.0\src\scfw_export_mx8dxl_a0\platform\board\mx8dxl_evk\board.c

============Code snippets=====================

err = irq_enable(3, SC_R_MU_1A, SC_IRQ_GROUP_WAKE, SC_IRQ_PAD, SC_TRUE);
board_print(1, "irq_enable %d...\n", err);

err = pad_set_wakeup(3, SC_P_SNVS_TAMPER_OUT4, SC_PAD_WAKEUP_RISE_EDGE);
board_print(1, "pad_set_wakeup %d...\n", err);

board_ddr_config(SC_FALSE, BOARD_DDR_SR_DRC_OFF_ENTER);

err = pm_req_cpu_low_power_mode(BOOT_PT, SC_R_A35 ,SC_PM_PW_MODE_OFF, SC_PM_WAKE_SRC_IRQSTEER_GIC );

=================================

Is my setting correct? I referred from <System Controller Firmware Porting Guide>.

It can put the A35 off but cannot wakeup.

(I suppose there should be a reset for A35, am I right?)

Thank you!

[hojames2025]

Our use case is:

1, Config some GPIO as wakeup source
2, Put A35 in LP/(or OFF) mode
3, set ddr in self fresh mode (is it necessay here?)
4, Execute WFI in A35
5, wakeup the A35 through the GPIO pad.
6, A35 wakes up, it can continue exceution or reset
7, A35 can re-use the data in ddr.

We don't want to change the scfw code if possible.
For now, the above step 1,2 3, are placed in SCU-FW directly just for test purpose.

Current issue is, Step 5 does not work.

I also changed to use the below parameter for step 2:

pm_req_cpu_low_power_mode(BOOT_PT, SC_R_A35_0 ,SC_PM_PW_MODE_LP, SC_PM_WAKE_SRC_SCU);

May be my approach is totally wrong?

One more question,
can the SCU also be in sleep/low power mode?

Thank you.

[AldoG]

Hello,

Please refer to the following community document:
https://community.nxp.com/t5/i-MX-Processors-Knowledge-Base/How-to-add-iMX8QXP-PAD-GPIO-Wakeup/ta-p/...

Best regards/Saludos,
Aldo.

[hojames2025]

Hello,

The document does not help in our case.

We are not using Linux as the OS.

We want to use the SCU-FW API (sc_fw_api_dxl_a0.pdf) to achieve this functionality.

Could you please share some guidelines about this?

Thank you.