From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: [PATCH] - Mapping ACPI tables as CACHED
Date: Tue, 14 Dec 2010 22:17:29 -0800
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References: <20101214220932.GA1206@sgi.com> <alpine.LFD.2.00.1012141903210.25387@x980> <20101215024136.GB19601@sgi.com> <alpine.LFD.2.00.1012142302110.4878@x980> <alpine.LFD.2.00.1012142317450.4878@x980>
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To: Len Brown <lenb@kernel.org>
Cc: Jack Steiner <steiner@sgi.com>, Henrique de Moraes Holschuh <hmh@hmh.eng.br>, tony.luck@gmail.com, linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, gbeshers@sgi.com

On 12/14/2010 08:35 PM, Len Brown wrote:
> 
> I'm not sure the concept of checking against E820
> is better than simply calling ioremap_cache() always.
> 

I don't think it is.  On most systems, non-RAM will be forced uncachable
by the MTRRs anyway, and if we find systems which have problems, we
should be doing this forcing in the PAT subsystem, not in ACPI.

	-hpa

-- 
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel.  I don't speak on their behalf.