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From: Peter Maydell <peter.maydell@linaro.org>
Date: Tue, 26 May 2015 14:52:25 +0100
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Subject: Re: [Qemu-devel] [PATCH v3 4/4] target-arm: Add the GICv2m to the
	virt board
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To: Eric Auger <eric.auger@linaro.org>
Cc: QEMU Developers <qemu-devel@nongnu.org>, Christoffer Dall <christoffer.dall@linaro.org>, "kvmarm@lists.cs.columbia.edu" <kvmarm@lists.cs.columbia.edu>

On 26 May 2015 at 14:07, Eric Auger <eric.auger@linaro.org> wrote:
> On 05/26/2015 02:55 PM, Peter Maydell wrote:
>> On 26 May 2015 at 13:54, Eric Auger <eric.auger@linaro.org> wrote:
>>> Reviewed-by: Eric Auger <eric.auger@linaro.org>
>>>
>>> The only question I have is related to mid-term virt strategy about
>>> GICv3 integration. Are we going to reuse that memory map for the machine
>>> instantiating the GICv3? If yes, shouldn't we put the GICv2M somewhere
>>> else to leave space for GICv3 redistributors, assuming we reuse the
>>> shared distributor region. I understood the memory map is difficult to
>>> change once applied once.
>>
>> I wouldn't expect that you'd have a GICv2M at all in a
>> system with a GICv3 in it, would you?
>
> no indeed. but we currently use a single static a15memmap memory map in
> virt. This one is currently planned to be reused for machines
> instantiating GICv3 so we start seeing things like
> VIRT_GIC_CPU =  VIRT_GIC_REDIST. I fear this is going to become messy.

I think the answer is not to reuse constant names like that.
The v3 redistributor is not a v2 CPU interface, just as a
UART is not an RTC.

-- PMM