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Date: Tue, 14 May 2013 15:53:29 +0200
From: Gerd Hoffmann <kraxel@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH RFC 00/13] qemu: generate acpi tables for
 the guest
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To: Anthony Liguori <anthony@codemonkey.ws>
Cc: seabios@seabios.org, lersek@redhat.com, qemu-devel@nongnu.org, "Michael S. Tsirkin" <mst@redhat.com>

  Hi,

>>> and is also a good
>>> reason why exposing this information via a common interface (fw_cfg)
>>> would be a good idea.
>>
>> Huh?  As far I know we generate device trees in qemu instead of
>> expecting pseries firmware compile them from fw_cfg information.
> 
> It depends on what firmware you are using.

Of course.  On archs which don't use device trees in the first place it
doesn't make sense.

> We don't really generate device trees in general in QEMU.

pseries does (thats why the hard libfdt dependency if you want pseries
support).  arm wants move into that direction too.

> As Peter mentioned, in an ideal world we'd generate them from the QOM
> graph.

Sure.

> That should happen in the firmware and it could be enabled by
> adding just a couple fw_cfg commands to navigate the QOM graph (analogs
> to qom-list and qom-get in QMP).

I don't think Peter intended to imply *that* ...

cheers,
  Gerd