From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: AHCI support Port Multiplier problem. Date: Tue, 11 Jan 2011 15:39:19 +0100 Message-ID: <20110111143919.GF30607@htj.dyndns.org> References: <20110107212537.GH7355@mtj.dyndns.org> <55871.3142.qm@web74203.mail.tp2.yahoo.com> <4D2BB855.5070703@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-bw0-f46.google.com ([209.85.214.46]:48664 "EHLO mail-bw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755469Ab1AKOjY (ORCPT ); Tue, 11 Jan 2011 09:39:24 -0500 Received: by bwz15 with SMTP id 15so20145787bwz.19 for ; Tue, 11 Jan 2011 06:39:22 -0800 (PST) Content-Disposition: inline In-Reply-To: <4D2BB855.5070703@gmail.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Robert Hancock Cc: Luo Dislo , jgarzik@pobox.com, linux-ide@vger.kernel.org Hello, On Mon, Jan 10, 2011 at 07:54:29PM -0600, Robert Hancock wrote: > I suspect that retrying with PMP=0 if the softreset with PMP=15 > failed to acquire a signature is likely the thing to do. Of the non-platform ones, sb600 is the only one with this problem and the workaround will unnecessarily lengthen response time for other controllers. I'd suggest implementing it as a quirk in libahci.c and applying it only to the broken controllers. Thanks. -- tejun