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Re: Does HIGHMEM work on 32-bit MIPS ports?

To: linux-mips@linux-mips.org
Subject: Re: Does HIGHMEM work on 32-bit MIPS ports?
From: David VomLehn <dvomlehn@cisco.com>
Date: Wed, 20 Feb 2008 11:20:33 -0800
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> I've written MIPS highmem support in late 2002 for a customer who
> back then wasn't interested in being the first through the 64-bit
> minefield. Which back then certainly was justified - but there are
> now fairly stable 64-bit Linux kernels available so if you happen to
> be running on 64-bit hardware don't even spend a nanosecond on
> thinking about 32-bit highmem kernels.  Highmem fundamentally sucks
> rocks through a straw.
>
> Coming back to your question.  Highmem was only ever tested to work
> on SB1 and somewhat later PMC-Sierra RM9000 cores, both being 64-bit.
> With the increasing maturity of 64-bit Linux interest in these went
> away and as the result the highmem code started a slow bitrot -
> unnoticed for many moons.

Hmm, this is not good. I've got a MIPS 24Kc processor with a very awkward memory layout. Any hints?

>   Ralf
--
David VomLehn, dvomlehn@cisco.com
The opinions expressed herein are likely mine, but might not be my employer's...

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