From owner-freebsd-hackers Mon Sep 6 12:49:43 1999 Delivered-To: freebsd-hackers@freebsd.org Received: from lestat.nas.nasa.gov (lestat.nas.nasa.gov [129.99.33.127]) by hub.freebsd.org (Postfix) with ESMTP id 28D7E15A29 for ; Mon, 6 Sep 1999 12:49:40 -0700 (PDT) (envelope-from thorpej@lestat.nas.nasa.gov) Received: from lestat (localhost [127.0.0.1]) by lestat.nas.nasa.gov (8.8.8/8.6.12) with ESMTP id MAA02493; Mon, 6 Sep 1999 12:49:18 -0700 (PDT) Message-Id: <199909061949.MAA02493@lestat.nas.nasa.gov> To: Wes Peters Cc: freebsd-hackers@FreeBSD.ORG Subject: Re: Tulip device driver question Reply-To: Jason Thorpe From: Jason Thorpe Date: Mon, 06 Sep 1999 12:49:17 -0700 Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Fri, 03 Sep 1999 16:23:00 -0600 Wes Peters wrote: > > > See, for instance, the al, ax, mx, pn, vr, and wb drivers. ;^) > > ^^ > > Especially this one.. it's not a Tulip clone :-) > > Oh? vr(4) disagrees: > > The VIA Rhine chips use bus master DMA and have a software interface de- > signed to resemble that of the DEC 21x4x "tulip" chips. I don't care what the manual page says; take a look at the respective programming manuals for the chips. Hell, take a look at if_vrreg.h and if_pnreg.h. The vast differences are *very* obvious. Really, the only thing that's even vaguely similar is that both of them use chained descriptors which are 16 bytes long, with similar layout (but not compatible bits within each longword). The registers are totally different. ...tho, I guess he did say "resemble" ... The SiS 900 "resembles" a Tulip, too (uses chained descriptors!), and the Tulip "resembles" the DEC SGEC (a lot more than the Rhine "resembles" the Tulip, tho :-) The various Tulip clones are actually somewhat close to Tulips (e.g. same registers, for the most part, same bits in the registers), and can be driven by the same driver, with various special cases in them for the (usually slight) differences [this is the approach I'm taking in NetBSD; why Bill didn't write a single driver for all the clones I'm not sure I'll ever know...] > I found the above list by grepping for "-i tulip" in /usr/src/sys/pci. It > is still a mystery to me why others don't do that before embarrassing them- > selves on a public mailing list... Hahaha.. Whatever :-) -- Jason R. Thorpe To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message