From mboxrd@z Thu Jan 1 00:00:00 1970 From: Philippe De Muyter Subject: Re: [PATCH ide] : Increase WAIT_DRQ to support slow CF cards Date: Tue, 27 Oct 2009 10:45:03 +0100 Message-ID: <20091027094503.GA3116@frolo.macqel> References: <51f3faa70910261807h54f05f73j48b67067ee3dde70@mail.gmail.com> <20091026.181922.261475236.davem@davemloft.net> <51f3faa70910261840v16444067uc323de7129b7592f@mail.gmail.com> <20091026.184318.205708741.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mailrelay007.isp.belgacom.be ([195.238.6.173]:8965 "EHLO mailrelay007.isp.belgacom.be" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752181AbZJ0JpO (ORCPT ); Tue, 27 Oct 2009 05:45:14 -0400 Content-Disposition: inline In-Reply-To: <20091026.184318.205708741.davem@davemloft.net> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: David Miller Cc: hancockrwd@gmail.com, linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org Hi David, On Mon, Oct 26, 2009 at 06:43:18PM -0700, David Miller wrote: > From: Robert Hancock > Date: Mon, 26 Oct 2009 19:40:03 -0600 > > > On Mon, Oct 26, 2009 at 7:19 PM, David Miller wrote: > >> Meanwhile we should provide a way for things to work, and > >> realistically the only way to do that currently is to bump the > >> WAIT_DRQ value to some large number. > >> > >> And that's exactly the kind of patch I'm willing to accept for this. > > > > I agree, it's sub-optimal but it helps.. if the user wants better > > behavior they should a) fix it so that the card isn't using PIO, at > > least if it supports DMA and b) not use drivers/ide.. Strangely enough, I also had no timeout problem if I started my kernel with 'ide=nodma', instead of increasing WAIT_DRQ. So I surmise that WAIT_DRQ is used in the dma case. > > Philippe's patch that started this thread uses "3 * HZ / 10" > which isn't large enough for the SSD cases. Can someone please > post a patch that uses a large enough value? How big a timeout do you want/accept ? Mark Lord wrote about SSD's in the mail referred by Robert Hancock : It should probably be at least 500msec or more now. Philippe