From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Lord Subject: Re: [PATCH #upstream] libata: implement libata.force module parameter Date: Thu, 14 Feb 2008 11:24:42 -0500 Message-ID: <47B46B4A.80708@rtr.ca> References: <47A3375F.80101@gmail.com> <47B2368D.9080408@gmail.com> <47B319C2.5030002@rtr.ca> <47B388B1.6050203@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]:4671 "EHLO mail.rtr.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753343AbYBNQYo (ORCPT ); Thu, 14 Feb 2008 11:24:44 -0500 In-Reply-To: <47B388B1.6050203@gmail.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Tejun Heo Cc: Jeff Garzik , IDE/ATA development list , Alan Cox Tejun Heo wrote: > Mark Lord wrote: >> Tejun Heo wrote: >>> This patch implements libata.force module parameter which can >>> selectively override ATA port, link and device configurations >>> including cable type, SATA PHY SPD limit, transfer mode and NCQ. >> ... >>> + libata.force= [LIBATA] Force configurations. The format is comma >>> + separated list of "[ID:]VAL" where ID is >>> + PORT[:DEVICE]. PORT and DEVICE are decimal numbers >>> + matching port, link or device. Basically, it matches >> .. >> >> Mmm.. not a NAK, but is there also a way to set/change these on the fly? > > What do you mean by 'on the fly'? While the system is running? If so, > I think that should be done through other interfaces - pass through, > sysfs, etc... .. Yes, that's the type of thing I had in mind. Some way to accomplish similar forced settings *after* libata is loaded. >> Now mind you, it's more likely the PCI layer that does the reverse >> order thing, but the end result is that my drives/ports are numbered >> differently depending upon which kernel I happen to boot with. > > Heck... That's ugly. libata.force is mainly conceived as debugging / > installation helper, so using fixed PORT is good enough but maybe > allowing bus_id as PORT is useful? Something like [00:1f.2]:00? .. It's just plain ugly the way it works, but livable (barely). We might actually have a use here for something similar to "ide=reverse", which was intended for exactly this kind of situation. But such usability flags seem to be in disfavour nowadays. Cheers!