Re: [Qemu-trivial] [Qemu-devel] [PATCH] RFC kvm irqfd: add directly mapped MSI IRQ support

[Michael S. Tsirkin]

On Fri, Jun 21, 2013 at 09:51:20AM +1000, Alexey Kardashevskiy wrote:
> And kvm_irqchip_add_msi_route does not have any link to a device or a bus
> so I'll have to walk through all PHBs in system and see if PHB's MSI window
> is the one from MSIMessage and convert MSIMessage to virq. Pretty easy and
> quick but still dirty hack, would it be better?

Yes I think that's fine really.

Basically devices all speak MSIMessage as they should -
this is what the PCI spec says.        
On all normal systems guests also speak MSIMessage so
the API which uses these makes sense for kvm.
Except, ppc architecture in its wisdom decided to hide this
in firmware.  QEMU does not have firmware so the translation
has to be maintained in QEMU powerpc code.

-- 
MST