From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robert Hancock Subject: Re: [PATCH 2.6.32.3] ahci: AHCI and RAID mode SATA patch for Intel Cougar Point DeviceIDs Date: Wed, 13 Jan 2010 18:11:43 -0600 Message-ID: <51f3faa71001131611y343ad225n1acc73900fd49894@mail.gmail.com> References: <201001121700.18234.seth.heasley@intel.com> <4B4D4EAA.2010109@gmail.com> <4B4DAA68.60608@pobox.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mail-iw0-f194.google.com ([209.85.223.194]:60217 "EHLO mail-iw0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756296Ab0ANALo convert rfc822-to-8bit (ORCPT ); Wed, 13 Jan 2010 19:11:44 -0500 In-Reply-To: <4B4DAA68.60608@pobox.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Jeff Garzik Cc: Seth Heasley , linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org On Wed, Jan 13, 2010 at 5:11 AM, Jeff Garzik wrote: >> Likely a lot of the existing specific PCI IDs could be removed from = the >> driver because of this (many likely predate the addition of the >> class-based catch-all). The only reason to need a specific entry if = the >> device uses AHCI class is if it needs special handling or workaround= s, >> which isn't the case here. > > Well, two lines of thinking here: > > * some of lines of Intel chips do not separate AHCI into a separate P= CI ID > rather legacy IDE interface. =A0When an AHCI interface exists and AHC= I/IDE > share the same PCI ID, we default to using AHCI. =A0Thus, some of tho= se PCI ID > matches in ahci.c's PCI table may not get caught by the generic PCI c= lass > match at the end of the table. Well, ata_piix does have a couple of entries that are listed in ahci as well, for ICH6 device IDs 0x2652 and 0x2653. For 0x2653 ata_piix checks the class code to make sure it's IDE, but for the 0x2652 entry, and in both cases in ahci, the class code isn't checked. Deleting the specific entries from ahci for those controllers would seemingly actually improve the situation, since then ahci wouldn't try and attach to those devices when they indicate IDE class. ata_piix should also should be checking for IDE class on 0x2652 as well.