From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Lord Subject: Re: [PATCH 09/10] sata_sil24: don't use NCQ if marvell 4140 PMP is attached Date: Sun, 18 May 2008 17:14:01 -0400 Message-ID: <48309C19.8090807@rtr.ca> References: <12111273141039-git-send-email-htejun@gmail.com> <12111273202036-git-send-email-htejun@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from rtr.ca ([76.10.145.34]:3521 "EHLO mail.rtr.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754069AbYERVOF (ORCPT ); Sun, 18 May 2008 17:14:05 -0400 In-Reply-To: <12111273202036-git-send-email-htejun@gmail.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Tejun Heo Cc: jeff@garzik.org, linux-ide@vger.kernel.org Tejun Heo wrote: > When 4140 PMP is attached to sil24, NCQ commands to fan out port 1 and > 2 (0 based) often stall if commands are in progress to other ports. > I've tried a number of things but can't tell what's going on. It > never happens w/ ahci and reportedly sata_mv which can issue NCQ > commands to multiple devices simultaneously like sil24 does. .. Mmm.. I wonder if sil24 is somehow triggering the "proprietary switching" mode of the 4140 -- this mode allows command-based-switching controllers to actually do something similar to FIS-based switching with the 4140. But I don't know how the 4140 decides to enter that mode.. I'll ping the Marvell folks again on that. Cheers