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Date: Tue, 17 Jul 2012 03:05:50 -0400
From: Jon Masters <jonathan@jonmasters.org>
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Subject: Re: [PATCH 00/36] AArch64 Linux kernel port
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On 07/16/2012 08:16 AM, Pavel Machek wrote:

>> If an implementation supports AArch32 at EL3 there could be some
>> physical (or some FPGA config) switch to choose between the two. But
>> since AArch64 is mandated, I don't see why one would force AArch32 at
>> EL3 and therefore all lower exception levels (and make a big part of the
>> processor unused).
> 
> Actually I see one ... and I can bet it will happen.
> 
> So you create that shiny new ARMv8 compliant CPU, 8 cores, 2GHz. HTC
> will want to use it with 1GB of RAM... and put around exiting OMAP
> perihepals.

But that's why we have Eagle (A15). It's a very capable 32-bit design
from ARM and far more sensible for such designs. You can easily build
something with a few A15 clusters in it, as we're already seeing.

Jon.