From owner-freebsd-hardware Fri May 8 10:52:44 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id KAA02524 for freebsd-hardware-outgoing; Fri, 8 May 1998 10:52:44 -0700 (PDT) (envelope-from owner-freebsd-hardware@FreeBSD.ORG) Received: from narnia.plutotech.com (narnia.plutotech.com [206.168.67.130]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id KAA02472 for ; Fri, 8 May 1998 10:52:26 -0700 (PDT) (envelope-from gibbs@narnia.plutotech.com) Received: (from gibbs@localhost) by narnia.plutotech.com (8.8.8/8.7.3) id LAA15388; Fri, 8 May 1998 11:48:37 -0600 (MDT) Date: Fri, 8 May 1998 11:48:37 -0600 (MDT) From: "Justin T. Gibbs" Message-Id: <199805081748.LAA15388@narnia.plutotech.com> To: Matthew Jacob cc: hardware@FreeBSD.ORG Subject: Re: [Target Mode] Was: Ooops - sorry Newsgroups: pluto.freebsd.hardware In-Reply-To: <199805050528.WAA14939@feral.com> User-Agent: tin/pre-1.4-971204 (UNIX) (FreeBSD/3.0-CURRENT (i386)) Sender: owner-freebsd-hardware@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org >>> I personally don't like Adaptec monopolizing the SCSI chip business. > > No, you misread me. Qlogic has a separate architecture and makes > their own chips. Orthogonal to NCR/Symbios and Adaptec. I was > just mentioning it as a possible viable Target mode platform > as opposed to trying to deduce target mode for Adaptec (or, rather, > doing the right microengine foo for the undocumented AIC sequencer), This is one of the large misconceptions about the Adaptec parts. The parts are documented and anyone on this list can call the technical documents department and have Adaptec send you the manuals. What differentiates Adaptec and Symbios from vendors like Qlogic is that they do not release their firmware in an easy to use binary module nor do they release the exact interface to their firmware. All the information you need to write your own firmware is provided. I should say that they don't release firmware *yet*, as one of Adaptec's technical marketting people is working to make the Adaptec HIM (Hardware Interface Module) available for a "free" driver. Even if this does happen, they will never release source to their firmware which, for vendors like Pluto, would make a HIM based driver much less attractive than the current one. Most of the bugs I fix or features I add to the aic7xxx driver have a 1 day turn around time. We could never get this kind of response from the vendor. There are also features that we plan to implement that would never interest Adaptec (being able to release target DMA memory mid transfer by using the "bit bucket" feature of the chip so our cache can be reused more quickly, for instance) that require firmware level tweaking. -- Justin To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hardware" in the body of the message