From owner-freebsd-questions Fri Apr 6 1:27:11 2001 Delivered-To: freebsd-questions@freebsd.org Received: from guru.mired.org (okc-65-26-235-186.mmcable.com [65.26.235.186]) by hub.freebsd.org (Postfix) with SMTP id 4AD6737B424 for ; Fri, 6 Apr 2001 01:27:08 -0700 (PDT) (envelope-from mwm@mired.org) Received: (qmail 69103 invoked by uid 100); 6 Apr 2001 08:27:07 -0000 From: Mike Meyer MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <15053.32219.89885.239143@guru.mired.org> Date: Fri, 6 Apr 2001 03:27:07 -0500 To: Glenn Johnson Cc: questions@freebsd.org Subject: Re: NEC IDE CD writer not working with burncd In-Reply-To: <75866052@toto.iv> X-Mailer: VM 6.90 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid X-face: "5Mnwy%?j>IIV\)A=):rjWL~NB2aH[}Yq8Z=u~vJ`"(,&SiLvbbz2W`;h9L,Yg`+vb1>RG% *h+%X^n0EZd>TM8_IB;a8F?(Fb"lw'IgCoyM.[Lg#r\ Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Glenn Johnson types: > On Thu, Apr 05, 2001 at 01:11:43PM +0100, Aleksandar Simic' wrote: > > Some IDE CDR aren't supported because they use proprietary IDE > > additions. I've learned that the same, hard way as you. > No one has been able to answer my question about this. Why is it that > these proprietary IDE additions that you refer to do not cause Linux to > trip? I know that Linux uses ide-scsi emulation and FreeBSD does not, > but shouldn't these proprietary IDE additions cause the ide-scsi module > loading to fail under Linux? Because the scsi-ide module doesn't care about the commands understood by the drive; it just arranges things so that applications can send SCSI commands that end up at IDE drives. The application in question - cdrecord - has to deal with the quirks of all the drives. It started doing this with SCSI drives before the standard for CDRW commands existed, so it does a pretty good job of it. Handling IDE drives once the kernel provides scsi-ide mapping is straightforward. In some cases it's even free, as the manufacturer uses the same command logic with a different bus interface. On the other hand, this is *not* something you want in the kernel. In fact, the stated policy for cd burners on FreeBSD is that FreeBSD supports cdrecord, which is a third party application. Both hooking ATA up to CAM - which would hook cdrecord up to ide devices - and making burncd work on the SCSI drives that follow the mmc standard have been discussed, but neither has happened. http://www.mired.org/home/mwm/ Independent WWW/Perforce/FreeBSD/Unix consultant, email for more information. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message