Re: [Qemu-devel] [PATCH 1/2] Route PC irqs to ISA bus instead of i8259 directly

[Alexander Graf]

Am 09.08.2009 um 18:44 schrieb Avi Kivity <address@hidden>:

> A PC has its motherboard IRQ lines connected to both the PIC and  
> IOAPIC.
> Currently, qemu routes IRQs to the PIC which then calls the IOAPIC, an
> incestuous arrangement.  In order to clean this up, create a new ISA  
> IRQ
> abstraction, and have devices raise ISA IRQs (which in turn raise  
> the i8259
> IRQs as usual).

Is this really true? From my understanding the PIC in modern systems  
is emulated through the IOAPIC, which is the reason we have legacy  
interrupts.

Copying the boot interrupt experts...

Alex