PANIC during wake up MPU

[alexey.b]

Hello.

I have a DK2 board and I want to wake up MPU (CA7) after shutdown command. If no MCU (CM4) firmware is running then no problems, but otherwise if I run MCU firmware (GPIO example) before shutting down MPU I get the following error after pushing Wake Up button:

PANIC at PC : 0x2fff2e81

Exception mode=0x00000016 at: 0xc0831f9c

And it reboots after some time and stops MCU firmware:

INFO:   Reset reason (0x214):

INFO:     IWDG2 Reset (rst_iwdg2)

How can i solve this problem?

Thanks.

[Olivier GALLIEN · Accepted solution]

Hi @alexey.b​ 

Trying to go in Standby with shutdown command required to stop the MCU first.

If you want to reach low power mode while MCU is running you shoud use echo 'mem' > /sys/power/state 

Please refer to AN5109 STM32MP1 Series using low-power modes 

Olivier

[alexey.b]

It looks like a bug in the Trusted Firmware-A.

But thanks anyway.