From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Lord Subject: Re: CF as IDE on ICH6M using libata Date: Mon, 10 Sep 2007 08:18:47 -0400 Message-ID: <46E53627.20101@rtr.ca> References: <6f9550040709020542h530f0bfap5b01fb4ff0c00f25@mail.gmail.com> <46DAB5DD.80807@gmail.com> <46DEE72B.2060702@rtr.ca> <6f9550040709051503k5b0a07b1x3e21bae3667ce17@mail.gmail.com> <46E03DF6.8090405@gmail.com> <46E1545A.5000404@rtr.ca> <46E24ADC.2000500@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from rtr.ca ([76.10.145.34]:4135 "EHLO mail.rtr.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756937AbXIJMSt (ORCPT ); Mon, 10 Sep 2007 08:18:49 -0400 In-Reply-To: <46E24ADC.2000500@gmail.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Tejun Heo Cc: Eddie Hung , linux-ide@vger.kernel.org Tejun Heo wrote: > Mark Lord wrote: >> Tejun Heo wrote: >>> Eddie Hung wrote: >>>> However, I think we can conclude that ICH6M (which on the X41, has a >>>> SATA-PATA bridge to connect a PATA drive) does not seem to support >>>> MWDMA >>> It isn't clear whether the fault is at the driver or the CF device. >> It's probably the bridge chip --> we've run through that one before >> just recently (early summer?) on this list. A particular bridge that >> doesn't work at all with MWDMA. > > Hmmm... How do we solve this situation? Till now, we've been > blacklisting the device IDs but it doesn't work for broken bridges. > Maybe we should default to not using MWDMA by default? Alan has observed that we really need to have a way to identify the bridge chip. But those seem to be mostly invisible to ordinary commands. Perhaps somebody at Marvell might give us the vendor-specific commands required to do this. Failing that, we cannot do it automatically, so we really do need some kind of boot/module/sysfs method for overriding libata's chosen transfer method. Blacklisting doesn't work here, because we really need to blacklist the invisible bridge chip, not the main chipset or the device. Cheers