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Subject: Re: [PATCH 2/2] pci: Use Qemu created PCI device nodes
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Alexey Kardashevskiy <aik@ozlabs.ru>
Date: Sat, 25 Apr 2015 21:25:57 +1000
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Cc: linuxppc-dev@ozlabs.org, Thomas Huth <thuth@redhat.com>,
 Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>, david@gibson.dropbear.id.au
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On Sat, 2015-04-25 at 17:31 +1000, Alexey Kardashevskiy wrote:
> We need BAR setup in 2 cases: when SLOF needs to boot from a PCI device 
> (and SLOF can do BAR setup) and when we do PCI hotplug - and BARs are set 
> by the guest, otherwise we hit races here (Michael Roth can tell more). So 
> as for today there is no reason for doing this in QEMU.

Doing BAR setup in the guest is a violation of PAPR though .... we do it now
to workaround bugs I believe but normally the BARs are expected to be owned
and setup by FW on a PAPR system.

Ben.