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Date: Mon, 11 Jul 2011 12:54:23 -0500
From: Timur Tabi <timur@freescale.com>
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To: Scott Wood <scottwood@freescale.com>
Subject: Re: RFC: top level compatibles for virtual platforms
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Cc: Wood Scott-B07421 <B07421@freescale.com>,
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	Alexander Graf <agraf@suse.de>, Gala Kumar-B11780 <B11780@freescale.com>
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Scott Wood wrote:
> The device tree is supposed to describe the hardware (virtual or
> otherwise), not just supply what Linux wants.  Perhaps there simply
> shouldn't be a toplevel compatible if there's nothing appropriate to
> describe there -- and fix whatever issues Linux has with that.

That might be the way to go.  I wonder if we can get rid of the platform file
altogether, at least in some situations.

> But what about this is specific to kvm (the actual hypervisor info is
> already described in /hypervisor)?  Then we'll have to add a platform match
> for every other hypervisor out there that does the same thing.

I don't know enough about KVM to answer that question.

Frankly, I like the approach that Topaz takes -- add a "-hv" to the real
hardware platform.  The only drawback is that each platform needs to add support
for virtualization, but we already have this problem with Topaz today.

-- 
Timur Tabi
Linux kernel developer at Freescale