In my custom FSBL on an STM32MP135AAE3, everything runs great except anytime I try to modify one of the GIC flags it pretty much ignores me completely (when I read it back, my changed bits aren't changed). I'm guessing this is some kind of trust zone or secure state or similar situation.
BTW, when I run my FSBL by setting the chip to serial boot and uploading it that way, it runs great, so I know the code is solid.
What do I need to change so my FSBL has full privileges? Is there a document that talks about this?
