From owner-freebsd-hackers Sat Jul 29 12:47:57 2000 Delivered-To: freebsd-hackers@freebsd.org Received: from netplex.com.au (adsl-63-207-30-186.dsl.snfc21.pacbell.net [63.207.30.186]) by hub.freebsd.org (Postfix) with ESMTP id 375A337B595 for ; Sat, 29 Jul 2000 12:47:55 -0700 (PDT) (envelope-from peter@netplex.com.au) Received: from netplex.com.au (peter@localhost [127.0.0.1]) by netplex.com.au (8.9.3/8.9.3) with ESMTP id MAA57344; Sat, 29 Jul 2000 12:47:29 -0700 (PDT) (envelope-from peter@netplex.com.au) Message-Id: <200007291947.MAA57344@netplex.com.au> X-Mailer: exmh version 2.1.1 10/15/1999 To: Garrett Rooney Cc: nimrodm@email.com, hackers@FreeBSD.ORG Subject: Re: Linux NVIDIA drivers vs. default XFree86 drivers (WAS: RE: Video card support) In-Reply-To: Date: Sat, 29 Jul 2000 12:47:29 -0700 From: Peter Wemm Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Garrett Rooney wrote: > On Sat, 29 Jul 2000, Nimrod Mesika wrote: > > > I thought the whole point of XFree4 new driver mechanism was that > > it was OS-neutral. It should be possible to run the same binary > > driver on all x86 platforms running XFree4 *without* recompiling. > > > > I don't know how this driver interacts with the kernel module, > > though. I'm not sure I even understand why a kernel module is > > needed in this case. > > i believe it requires hooks into the kernel to make use of AGP, which is > necessary for high performance 3d rendering. More to the point, they want to use their high performance proprietary internal cross platform driver that they also use on Windows etc. They provide the OS interface glue to enable interfacing with the kernel. The driver then completely takes over the card management in kernel context - busmaster DMA, command fifo managenent, card memory management, the lot. A userland XFree driver cannot use DMA as it cannot know what the virtual-> physical address mappings are. Cheers, -Peter -- Peter Wemm - peter@FreeBSD.org; peter@yahoo-inc.com; peter@netplex.com.au "All of this is for nothing if we don't go to the stars" - JMS/B5 To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message