[coreboot] AMD platform: IO-APIC => Local APIC delivery modes

[Andriy Gapon]

On 09/10/2016 23:41, Rudolf Marek wrote:
> Great, so there is a bug! Do you have some USB image I can try on more recent
> AMD system (with Hudson chipset). Or we can try to report this to AMD, but I
> have read somewhere that the new chipsets are done by Asmedia.

I did most of the testing using two small programs, one to examine the IO-APIC
redirection table and the other to write its entries:
https://people.freebsd.org/~avg/ioapic.c
https://people.freebsd.org/~avg/ioapic_wr.c
Another thing required is an interrupt that can be reliably triggered in a
controllable fashion (like a mouse interrupt or a timer interrupt).  In my case
I used an interrupt from the watchdog timer.

So, I would just directly re-program a pin corresponding to the interrupt and
then trigger the interrupt and see what happens.

An example:
$ ioapic_wr 3 0xff00000000000300

-- 
Andriy Gapon