how to restart Cortex-A53 alone without impact on Cortex-M7

[eone]

Hi, NXP
I am using BSP33.0 on s32g274ardb2.

1. When I run the "reboot" command on the linux with core A, the M7 core will also restart.
Is there any configuration that can restart the A core independently without affecting the M7 core ?

2. When the M core crash abnormally, it will also cause the A core to break down,
and the system log of the A core can not record the reason for the forced restart.
Is there a method to record logs of  above scene ?

[eone]

Thank you for your reply.

After our verification, the command "halt" can shut down core A alone, while core M does not shut down or restart, command "halt  --reboot" restarts both core A and core M. We want to find the way to restart kernel A alone.

[MayanksPatel]

Hi @eone,

By performing a halt operation, the kernel gets restarted on Core-A. What you are looking for apart from that?

[eone]

HI. Thank you very much for your patient reply.
We are looking for a way to restart the A53 core separately while keeping the M7 core running.
The "halt " command can only shut down core-A5, not restart it.

[MayanksPatel]

Hi @eone,

Resetting the A53 core without impacting the M7 core is possible but there are no commands available for that. You need to read the reference Manual A53 Reset Sequence and develop code for the same.

A53 core is running Linux OS and suggested not resetting it as it can corrupt the OS Functionalities. 

Thanks,

Mayank S Patel

[MayanksPatel]

Hi @eone,

Thank you for reaching out to us.

Please find the answer below:

1. you can use the "halt" command for independently resetting the A53 core. This will not reset the M7 core.

2. Please follow the steps for preserving system logs.

1. Open /etc/fstab file.
2. comment the line "tmpfs /var/volatile tmpfs defaults 0 0".
3. restart the board.
4. You can see the older and current logs in the file "/var/volatile/log/kern.log".

Hope this helps.

Thanks,

Mayank S Patel