Re: [Qemu-devel] [RFC 3/3] acpi-build: allocate mcfg for multiple host bridges

[Laszlo Ersek]

On 05/23/18 01:40, Michael S. Tsirkin wrote:
> On Wed, May 23, 2018 at 12:42:09AM +0200, Laszlo Ersek wrote:
>> Hold on,
>>
>> On 05/22/18 21:51, Laszlo Ersek wrote:
>>
>>> It had taken years until the edk2 core gained a universal
>>> PciHostBridgeDxe driver with a well-defined platform customization
>>> interface, and that interface doesn't support multiple domains /
>>> segments.
>>
>> after doing a bit more research: I was wrong about this. What I
>> remembered was not the current state. Edk2 does seem to support multiple
>> domains, with different segment numbers, ECAM base addresses, and bus
>> number ranges. If we figure out a placement strategy or an easy to
>> consume representation of these data for the firmware, it might be
>> possible for OVMF to hook them into the edk2 core (although not in the
>> earliest firmware phases, such as SEC and PEI).
>>
>> In retrospect, I'm honestly surprised that so much multi-segment support
>> has been upstreamed to the edk2 core. Sorry about the FUD. (My general
>> points remain valid, for the record... But perhaps they no longer matter
>> for this discussion.)
>>
>> (I meant to send this message soon after
>> <http://mid.mail-archive.com/address@hidden>,
>> but my internet connection had to die right then.)
>>
>> Thanks
>> Laszlo
> 
> Is there support for any hardware which we could emulate?

I don't see any actual hw support in the edk2 project, but I'll ask.

Thanks
Laszlo