interrupts on AMD hardware

[Christian Helmuth]

Hello,

first I'd like to thank Ben for providing me his ACPI tables.

This morning I digged through the disassembled DSDT and got the
feeling that this AMD platforms depends on an ACPI-capable OS calling
the _PIC and _PRT methods for IRQ setup. This is the call trace I
discovered

call _PIC to inform AML of the interrupt model in use
  _PIC calls \_SB.IRQC in APIC mode
    \_SB.IRQC configures several SystemIO fields (e.g., PIRA, PIRB)

_PRT reports the routing table as usual referencing AR00 in APIC mode
so this part should be working already. I suggest further
investigation of the IRQ-related setup done in the DST AML code.
Unfortunately, I'm not familiar enough with acpica to know if it could
be easily adapted to try a full ACPI setup (incl. IRQs) on the
platform.

Regards
-- 
Christian Helmuth
Genode Labs

https://www.genode-labs.com/ · https://genode.org/
https://twitter.com/GenodeLabs · /ˈdʒiː.nəʊd/

Genode Labs GmbH · Amtsgericht Dresden · HRB 28424 · Sitz Dresden
Geschäftsführer: Dr.-Ing. Norman Feske, Christian Helmuth