From owner-freebsd-bugs Sat Feb 12 21: 5: 2 2000 Delivered-To: freebsd-bugs@freebsd.org Received: from caspian.plutotech.com (caspian.plutotech.com [206.168.67.80]) by builder.freebsd.org (Postfix) with ESMTP id 58DB83FEF; Sat, 12 Feb 2000 21:04:57 -0800 (PST) Received: from caspian.plutotech.com (localhost [127.0.0.1]) by caspian.plutotech.com (8.9.3/8.9.1) with ESMTP id WAA02124; Sat, 12 Feb 2000 22:05:26 -0700 (MST) (envelope-from gibbs@caspian.plutotech.com) Message-Id: <200002130505.WAA02124@caspian.plutotech.com> X-Mailer: exmh version 2.1.0 09/18/1999 To: tkuehn@websurf.pcom.de (Torsten Kuehn) Cc: freebsd-bugs@FreeBSD.ORG, ken@plutotech.com, wilko@FreeBSD.ORG Subject: Re: ahb Bug still not resolved in 3.2-release (ref. kern/12495) In-reply-to: Your message of "Sat, 12 Feb 2000 22:26:31 GMT." <000212222503224400@mail1.pcom.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Sat, 12 Feb 2000 22:05:25 -0700 From: "Justin T. Gibbs" Sender: owner-freebsd-bugs@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org There are several things that the FreeBSD driver does that the Linux driver does not. 1) We will issue tagged commands. 2) We tell the firmware to only update the status block on error. 3) We tell the firmware to not auto-retry on BUSY status. The CAM peripheral driver will retry if it wishes. 4) We don't suppress underrun errors. Since we tell the firmware to only update the status block on errors, this is the only way to get a valid residual. 5) We don't have the controller check that data flows in the proper direction. The code is there, but it is currently commented out for some reason. I don't remember doing this myself. It may be that any or all of the above are features of the firmware that were never exercised by other drivers and so are buggy. Do you have a system where you can generate kernels? Perhaps you can change the driver to behave just like the Linux one and then enable the use of the above features one by one until an error occurs? That is, hoping that by mimicking the Linux driver the errors go away. 8-) -- Justin To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-bugs" in the body of the message