IRQ routing

[StjepanPoljak]

Hi, I've been trying out something for myself on Raspberry Pi, and I even tried making my code identical to yours... But what I noticed, when we are in hypervisor mode, we (or at least I) have to route IRQs. That is accomplished by writing 0x10 to hcr_el2 (short explanation is IRQs are taken to EL2 unless routed to EL3). Anyway, I don't know if this is an issue, but I wonder if something else is amiss with my method.

[ashwio]

Hi @StjepanPoljak sorry for the very delay in responding, I haven't visited GItHub in a long time. Please can you expand/clarify your question a bit? I'm unsure what you're asking.

If it helps, IRQs are routed to EL1 by default and you can never take an exception to a lower EL. That means if you're currently running in EL2 and an IRQ becomes pending, you won't actually take the IRQ until you drop back down to EL1. Setting HCR_EL2.IMO routes IRQs to EL2 instead.

The code in the repo doesn't do this yet because it doesn't actually handle any IRQs.