From owner-freebsd-current@FreeBSD.ORG Fri Jul 30 20:27:56 2004 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id DDADA16A4CE for ; Fri, 30 Jul 2004 20:27:56 +0000 (GMT) Received: from spider.deepcore.dk (cpe.atm2-0-53484.0x50a6c9a6.abnxx9.customer.tele.dk [80.166.201.166]) by mx1.FreeBSD.org (Postfix) with ESMTP id 3E91D43D54 for ; Fri, 30 Jul 2004 20:27:56 +0000 (GMT) (envelope-from sos@DeepCore.dk) Received: from [192.168.0.132] ([192.168.0.132]) by spider.deepcore.dk (8.12.11/8.12.10) with ESMTP id i6UKQJ7s015795; Fri, 30 Jul 2004 22:26:24 +0200 (CEST) (envelope-from sos@DeepCore.dk) Message-ID: <410AAEE4.7070409@DeepCore.dk> Date: Fri, 30 Jul 2004 22:26:12 +0200 From: =?ISO-8859-1?Q?S=F8ren_Schmidt?= User-Agent: Mozilla Thunderbird 0.7.1 (X11/20040711) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Chuck Swiger References: <410A3833.7030502@portaone.com> <410A47C7.1080808@DeepCore.dk> <410A9B58.8000502@mac.com> <410A9D77.4030703@DeepCore.dk> <410AA5A5.4000001@mac.com> In-Reply-To: <410AA5A5.4000001@mac.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 8bit X-mail-scanned: by DeepCore Virus & Spam killer v1.4 cc: Maxim Sobolev cc: current@freebsd.org Subject: Re: Is there still sufficient reason for hw.ata.atapi_dma being 0 by default? X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 30 Jul 2004 20:27:57 -0000 Chuck Swiger wrote: > Søren Schmidt wrote: >> Actually not, most if not all modern fast burners implements some sort >> of "burn proof" ie no coasters at all due to buffer underruns... > > You're right that truly modern fast burners ought to implement > "justlink" or "burn proof". However, I don't think it's a good idea to > depend on the burner to be able to handle underruns; I'd rather run > CD/DVD burners using UDMA. > > [ FWIW, I've got a 16/10/40x Yamaha burner which just predates the first > generation of burners with underrun protection-- this affects me > directly. ] Hmn, you should be able to burn 16x in PIO4 mode... >> Not really, the problem with ATAPI dma is that if it fails it most >> likely locks up the machine, so there is no way to back pedal... > Oh. Ewww. Could chipsets which do that be added to a "quirks" table > similar to the way USB devices are being handled? Or is it not just the > chipset, but some more complex interaction between ATAPI DMA and other > devices in the system which want to do DMA which causes the lockup? Right, its a combination of chipset and device, the matrix would be impossible to maintain. -Søren