From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1755433Ab0HCHFV (ORCPT <rfc822;w@1wt.eu>);
	Tue, 3 Aug 2010 03:05:21 -0400
Received: from one.firstfloor.org ([213.235.205.2]:50176 "EHLO
	one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1755229Ab0HCHFU (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Tue, 3 Aug 2010 03:05:20 -0400
Date: Tue, 3 Aug 2010 09:05:14 +0200
From: Andi Kleen <andi@firstfloor.org>
To: Pavel Machek <pavel@ucw.cz>
Cc: Len Brown <lenb@kernel.org>, Matthew Garrett <mjg59@srcf.ucam.org>,
        "Yu, Luming" <luming.yu@intel.com>,
        Philip Langdale <philipl@overt.org>, Jeff Garrett <jeff@jgarrett.org>,
        Andi Kleen <andi@firstfloor.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        "linux-acpi@vger.kernel.org" <linux-acpi@vger.kernel.org>,
        "venki@google.com" <venki@google.com>
Subject: Re: [PATCH] ACPI: make acpi_idle Nehalem-aware
Message-ID: <20100803070514.GA31096@basil.fritz.box>
References: <alpine.LFD.2.00.1004301218280.2489@sony>
 <20100430174447.GA14889@srcf.ucam.org>
 <d7f2dd35a4361e5156079278543769a0@localhost>
 <alpine.LFD.2.00.1005250125590.20648@localhost.localdomain>
 <CE761E84DADF2947A4AF22FB8D97A4731E0366B5@shsmsx501.ccr.corp.intel.com>
 <20100525124325.GC7876@srcf.ucam.org>
 <alpine.LFD.2.00.1005251114420.4114@localhost.localdomain>
 <20100525185507.GA15997@srcf.ucam.org>
 <alpine.LFD.2.00.1007211729550.409@localhost.localdomain>
 <20100803065514.GE3344@ucw.cz>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20100803065514.GE3344@ucw.cz>
User-Agent: Mutt/1.5.20 (2009-06-14)
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Tue, Aug 03, 2010 at 08:55:14AM +0200, Pavel Machek wrote:
> On Wed 2010-07-21 17:31:27, Len Brown wrote:
> > From: Len Brown <len.brown@intel.com>
> > 
> > The BIOS exports deep C-states on modern Intel processors
> > as "C3-type" to satisfy various legacy Operating Systems.
> 
> Can you elaborate on this? I though the only difference between
> C2-type and C3-type is busmastering...

The main difference is latency.

-Andi

-- 
ak@linux.intel.com -- Speaking for myself only.