Re: [Qemu-devel] [PATCH 2/4] pci: Add generic PCIe host bridge

[Claudio Fontana]

On 12.01.2015 22:20, Peter Maydell wrote:
> On 12 January 2015 at 21:06, Alexander Graf <address@hidden> wrote:
>>
>>
>> On 12.01.15 21:08, Peter Maydell wrote:
>>> On 12 January 2015 at 17:38, Alexander Graf <address@hidden> wrote:
>>>> I'd prefer to keep things as easy as we humanly can for now. Then add
>>>> MSI. And if we then realize that we still need 4 rather than 1 shared
>>>> interrupt lines we can still change it :)
>>>
>>> Except that that would be a breaking change, so I would prefer
>>> to think ahead where possible; at some point there will come
>>> a time when we really can't make breaking changes to this
>>> board any more...
>>
>> Works for me, then we stay at a single interrupt line. The only reason
>> we have 4 in PCI is that back in the day you could have non-sharing PCI
>> devices that were essentially ISA ones.
> 
> Well, also your typical small system probably doesn't have more
> than 4 PCI slots and so 4 IRQs is enough to give them each one.
> Most small VMs probably won't have more than four PCI devices
> either...
> 
> -- PMM
> 

This solution with 4 slots, 4 irqs would be preferable to me..

Ciao,

Claudio