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From: Kumar Gala <galak@kernel.crashing.org>
Subject: Re: FSL vs. IBM BookE
Date: Sat, 4 Nov 2006 10:56:17 -0600
To: Josh Boyer <jwboyer@jdub.homelinux.org>
Cc: Paul Mackerras <paulus@samba.org>, Kumar Gala <galak@gate.crashing.org>,
	linuxppc-dev list <linuxppc-dev@ozlabs.org>
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On Nov 4, 2006, at 10:16 AM, Josh Boyer wrote:

> On Sat, 2006-11-04 at 20:21 +1100, Benjamin Herrenschmidt wrote:
>> Out of curiosity... I noticed we have both head_44x.S and
>> head_fsl_booke.S, the later being a fork of the former with  
>> changed from
>> Kumar (and possibly others) to support E200 and E500.
>>
>> How bad are the differences between those cores ? Would it be  
>> possible
>> to reconcile those and IBM 44x into a single processor family ? Or  
>> are
>> there some fundamental differences making that impossible ? (even  
>> with a
>> bit of CPU feature patching).
>
> I'm not sure.  Maybe Kumar knows better since he made the changes to
> head_fsl_booke.S.  I believe FSL can do SMP and has an SPE and some
> other HID registers that 44x does not have.

The big differences are in MMU architectures/programming models  
between 44x and FSL Book-E.  I tried to move as much common code into  
macros between the two head_* files.

- kumar