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Message-ID: <1348147826.26501.47.camel@zakaz.uk.xensource.com>
Subject: Re: [PATCH] arm: introduce a DTS for Xen unprivileged virtual
 machines
From: Ian Campbell <Ian.Campbell@citrix.com>
To: Marc Zyngier <marc.zyngier@arm.com>
CC: Stefano Stabellini <Stefano.Stabellini@eu.citrix.com>,
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	<linux-arm-kernel@lists.infradead.org>,
        Arnd Bergmann <arnd@arndb.de>
Date: Thu, 20 Sep 2012 14:30:26 +0100
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On Thu, 2012-09-20 at 13:28 +0100, Marc Zyngier wrote:
> I think the important thing here is that the memory map is RS1. As this
> is a (very limited) subset of a vexpress A15, it seems to make some sense.

Looking at arch/arm/boot/dts/vexpress-v2m-rs1.dtsi I don't think we
provide anything which is on rs1 though.

The Xen VM environment has only a gic (via a combination of the gic
virtualisation mode for CPU regs and emulation for the distributor), the
arch timers and xenbus (which is the s/w bus which Xen uses to discover
its paravirtualised peripherals).

Currently we provide a very simple output only emulation of UART0,
simply to get the debug output from the decompresser, but we want that
to go away not get baked in.

Ian.