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Subject: Re: [patch] vesafb fix
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Dave Jones <davej@codemonkey.org.uk>
Cc: Jamie Lokier <jamie@shareable.org>, Gerd Knorr <kraxel@suse.de>,
       Linus Torvalds <torvalds@transmeta.com>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
       Andi Kleen <ak@suse.de>
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Date: 15 Jul 2003 19:46:03 +0100
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On Maw, 2003-07-15 at 19:22, Dave Jones wrote:
> I can't see how you can cover an not-a-powerof2 size area of memory
> without doing too little/too much. The winchip code was written with
> RAM in mind, which is always a power of 2 unless you boot with
> mem=fooMB

RAM is never power of two, a few bits always vanish off the ends.
The trick is that you start at a power of 2 boundary then build up/down
if you have to do power of two ranges