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Re: [patch] linux: cpu_probe(): remove 32-bit CPU bits for MIPS64

To: Ralf Baechle <ralf@oss.sgi.com>
Subject: Re: [patch] linux: cpu_probe(): remove 32-bit CPU bits for MIPS64
From: "Maciej W. Rozycki" <macro@ds2.pg.gda.pl>
Date: Wed, 24 Jul 2002 17:05:52 +0200 (MET DST)
Cc: "Kevin D. Kissell" <kevink@mips.com>, linux-mips@fnet.fr, linux-mips@oss.sgi.com
In-reply-to: <20020724165239.F28010@dea.linux-mips.net>
Organization: Technical University of Gdansk
Ralf,

> >  I don't think it's possible to be fully achieved.  Some differences will
> > have to exist, at least in the headers, but likely within the arch tree as
> > well.  The reason is binary code size or perfomance -- having R3000
> > support code in mips64 binaries is simply ridiculous as is using 32-bit
> > operations with 64-bit data on a 64-bit CPU.  However, it is worth trying
> > to minimize visible differences where possible, e.g. by convincing the
> > compiler to optimize irrelevant bits away.
> 
> In this particular case all the bloat is just in __init code, could that
> convince you?

 Nope, sorry.  I'm by all means for keeping any questionable but at least
remotely useful code under the __init justification.  But in this case,
the code will never, ever be used.

 As I stated, I'm going to look deeper at the issue.  Just let it exist as
is for now, until me (or someone else) invents an improvement.  To state
it explicitly: yes, I'm going to keep a single source for both paths and
convince the compiler somehow to rip unneeded bits in the 64-bit case.

-- 
+  Maciej W. Rozycki, Technical University of Gdansk, Poland   +
+--------------------------------------------------------------+
+        e-mail: macro@ds2.pg.gda.pl, PGP key available        +

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