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Subject: Re: [RFC PATCH 1/2] powerpc/xive: guest exploitation of the XIVE
 interrupt controller
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: David Gibson <david@gibson.dropbear.id.au>, =?ISO-8859-1?Q?C=E9dric?=
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Date: Wed, 05 Jul 2017 09:38:20 -0500
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On Wed, 2017-07-05 at 21:07 +1000, David Gibson wrote:
> I don't know if it helps, but we do have the ability to trigger a full
> system reset from CAS, so possibly we can do the XICS/XIVE
> instantiation in the reset path.
> 
> I don't think we use that CAS reset ability yet - we just adjust the
> device tree and continue the boot.  But it's there if we need it.
> 
> Worst comes to worst, we might have to instantiate both XICS and XIVE
> objects, with some flags in each indicating which is active.

That could be a problem with the kernel interrupt controller. We can't
really instantiate both there I think... well, actually ... maybe we
could, though it's a bit messy...

Cheers,
Ben.