SError interrupt

I’m working on bare-metal firmware for the Rock Pi 4B. One of the interrupts I receive is a SError interrupt which I don’t really expect. Has anyone else encountered such a behaviour or do you use the SError interrupt for any particular feature on the Rock Pi?

bare-metal? Wow, let’s welcome the warrior. How do you debug and where is yoru code based? Not sure what is a SError, can you give more info?

We develop a provable, secure hypervisor as Type I, so it runs directly on the hardware without any other OS. This is a university research project. We debug via UART outputs. A SError is poorly documented but an explanation can be found in the official ARM manuals.

Basically we want to find out what may trigger this interrupt and we are getting closer. I was hoping that anyone has experience with the SoC of the RockPi and may know what can cause such an Exception.

To be honest, I haven’t had any experience with the FUSB302 yet, so my question is about the exceptions. Does the FUSB302 need some care during the cold start and could this chip trigger the exceptions? Just such an idea from the gut.

The SError was caused when we used the bootm command from uboot. Booting from SD card or using booti works fine. We do not know why this error occurs. We also used the Armbian u-boot.

https://static.docs.arm.com/100933/0100/aarch64_exception_and_interrupt_handling_100933_0100_en.pdf