Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758896Ab0BYDPV (ORCPT ); Wed, 24 Feb 2010 22:15:21 -0500 Received: from snt0-omc3-s25.snt0.hotmail.com ([65.55.90.164]:6194 "EHLO snt0-omc3-s25.snt0.hotmail.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758780Ab0BYDPR convert rfc822-to-8bit (ORCPT ); Wed, 24 Feb 2010 22:15:17 -0500 Message-ID: X-Originating-IP: [96.253.143.208] From: Yuhong Bao To: , CC: , , , Subject: RE: [PATCH 2.6.34] ehci-hcd: add option to enable 64-bit DMA support Date: Wed, 24 Feb 2010 19:15:16 -0800 Importance: Normal In-Reply-To: <4B85E038.20905@kernel.org> References: <4B7CAF95.6020306@gmail.com> <20100218052223.GA13254@kroah.com> <51f3faa71002181633w1649a648s37ae73da342d0c3f@mail.gmail.com> <201002192139.46189.david-b@pacbell.net> <51f3faa71002192315ia84786eo1138bf9ab3417f2d@mail.gmail.com> <51f3faa71002231626q1eb62adeo660c282418f0e01@mail.gmail.com>,<4B85E038.20905@kernel.org> Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT MIME-Version: 1.0 X-OriginalArrivalTime: 25 Feb 2010 03:15:16.0700 (UTC) FILETIME=[C0D8C9C0:01CAB5C8] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1114 Lines: 25 > (following thread from the ATA side) I'm with Greg on this. USB2.0 is > quite slow on today's standard and most 64bit machines now have IOMMU > of some kind anyway. Except that unfortunately, Intel with Lynnfield and Clarkdale decided to do market segmentation on the VT-d feature. This could be done because both have an integrated northbridge. With Lynnfield, the very common Core i5 750 CPU do not support VT-d, but the Core i7 800 series does. With Clarkdale, the very common Core i3 500 series do not support VT-d, but the Core i5 600 series does, except the 661. Not to mention that in the Core 2 generation, VT-d was available only on Q35/Q45/X38/X48 chipsets. Yuhong Bao _________________________________________________________________ Hotmail: Trusted email with powerful SPAM protection. http://clk.atdmt.com/GBL/go/201469227/direct/01/-- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/