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Subject: Re: [PATCH] x86: Reserve legacy VGA MMIO area for x86_64 as well
 as x86_32
From: Guenter Roeck <guenter.roeck@ericsson.com>
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To: "H. Peter Anvin" <hpa@zytor.com>, linux-kernel@vger.kernel.org
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Organization: Ericsson
Date: Fri, 9 Apr 2010 14:01:02 -0700
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On Fri, 2010-04-09 at 16:44 -0400, H. Peter Anvin wrote:
> On 04/09/2010 01:31 PM, Guenter Roeck wrote:
> > 
> > It is used for a custom FPGA implementing a watchdog timer and some
> > other functionality.
> > 
> > This is not a matter of supporting such a device in Linux, it is a
> > matter of explicitly excluding non-VGA devices from using VGA memory
> > space.
> > 
> > If that is the decision, it might be worthwhile mentioning it somewhere
> > in the documentation, to prevent others from ever using that memory
> > space in an embedded system (and to save them the time needed to find
> > out about it and to identify and implement a workaround).
> > 
> 
> "Don't use legacy fixed-function addresses for nonstandard purposes."
> 
> There, there is your documentation.

Fair and good enough, as long as it is going to show up somewhere.

Guenter