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Date: Tue, 7 Jan 2014 09:29:57 +0100
From: =?UTF-8?B?Um9nZXIgUGF1IE1vbm7DqQ==?= <roger.pau@citrix.com>
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To: Julien Grall <julien.grall@linaro.org>, <freebsd-xen@freebsd.org>,
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Subject: Re: [Xen-devel] [PATCH v9 15/19] xen: create a Xen nexus to use in
 PV/PVH
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On 06/01/14 12:33, Julien Grall wrote:
> 
> 
> On 01/06/2014 09:35 AM, Roger Pau Monné wrote:
>> On 05/01/14 22:55, Julien Grall wrote:
>>>
>>>
>>> On 01/02/2014 03:43 PM, Roger Pau Monne wrote:
>>>> Introduce a Xen specific nexus that is going to be in charge for
>>>> attaching Xen specific devices.
>>>
>>> Now that we have a xenpv bus, do we really need a specific nexus for
>>> Xen?
>>> We should be able to use the identify callback of xenpv to create the
>>> bus.
>>>
>>> The other part of this patch can be merged in the patch #14 "Introduce
>>> xenpv bus and a dummy pvcpu device".
>>
>> On x86 at least we need the Xen specific nexus, or we will fall back to
>> use the legacy nexus which is not what we really want.
>>
> 
> Oh right, in any case can we use the identify callback of xenpv to add
> the bus?

AFAICT this kind of bus devices don't have a identify routine, and they
are usually added manually from the specific nexus, see acpi or legacy.
Could you add the device on ARM when you detect that you are running as
a Xen guest, or in the generic ARM nexus if Xen is detected?

Roger.