From owner-p4-projects@FreeBSD.ORG Mon Apr 25 06:50:27 2005 Return-Path: Delivered-To: p4-projects@freebsd.org Received: by hub.freebsd.org (Postfix, from userid 32767) id CC57316A4D0; Mon, 25 Apr 2005 06:50:26 +0000 (GMT) Delivered-To: perforce@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 9976C16A4CE for ; Mon, 25 Apr 2005 06:50:26 +0000 (GMT) Received: from ns1.xcllnt.net (209-128-86-226.bayarea.net [209.128.86.226]) by mx1.FreeBSD.org (Postfix) with ESMTP id 3AA6C43D39 for ; Mon, 25 Apr 2005 06:50:26 +0000 (GMT) (envelope-from marcel@xcllnt.net) Received: from [192.168.4.250] (dhcp50.pn.xcllnt.net [192.168.4.250]) by ns1.xcllnt.net (8.13.3/8.13.3) with ESMTP id j3P6n9VO057583; Sun, 24 Apr 2005 23:49:09 -0700 (PDT) (envelope-from marcel@xcllnt.net) In-Reply-To: <20050425.003757.74682881.imp@bsdimp.com> References: <200504250459.j3P4xWxs057683@repoman.freebsd.org> <20050424.234915.41699183.imp@bsdimp.com> <20050425.003757.74682881.imp@bsdimp.com> Mime-Version: 1.0 (Apple Message framework v622) Content-Type: text/plain; charset=US-ASCII; format=flowed Message-Id: <0ed61916398fb3960649890399e2345b@xcllnt.net> Content-Transfer-Encoding: 7bit From: Marcel Moolenaar Date: Sun, 24 Apr 2005 23:49:08 -0700 To: "M. Warner Losh" X-Mailer: Apple Mail (2.622) cc: Perforce Change Reviews Subject: Re: PERFORCE change 75921 for review X-BeenThere: p4-projects@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: p4 projects tree changes List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 25 Apr 2005 06:50:27 -0000 On Apr 24, 2005, at 11:37 PM, M. Warner Losh wrote: > In message: > Marcel Moolenaar writes: > : > : On Apr 24, 2005, at 10:49 PM, M. Warner Losh wrote: > : > : > In message: <200504250459.j3P4xWxs057683@repoman.freebsd.org> > : > Marcel Moolenaar writes: > : > : http://perforce.freebsd.org/chv.cgi?CH=75921 > : > : > : > : Change 75921 by marcel@marcel_nfs on 2005/04/25 04:59:01 > : > : > : > : Allow VGA resources across PCI-PCI bridges. Required to > : > : support a PCI based VGA driver with the VGA hardware > : > : behind a PCI-PCI bridge. > : > > : > WE need to make sure that the ISA bit and VGA bits are set > properly on > : > those bridges with vga children and peers of bridges with vga > : > children before allowing this... > : > : Ideally, yes. But since only one PCI device of class display and > : subclass VGA can have the legacy VGA addresses enabled and we're > : not mucking with the system configuration in that respect, we're > : not really doing anything dangerous by allowing the VGA addresses > : without such scrutiny provided we don't try to allocate those > : addresses for any ol' VGA display device that we find on the PCI > : busses in the system. > > Actually yes, really, we need to do this. Most system BIOSes will get > it right, but not all. I think that means we already have problems with syscons(4) then on those machines, right? I mean, syscons just peeks and pokes at the addresses and if it gets something it expects, then there's a VGA device. Allowing VGA addresses across PCI-PCI bridge devices yields exactly the same: some newbusified driver starts to peek and poke at the VGA addresses and if it gets something it expects, then the device can attach. -- Marcel Moolenaar USPA: A-39004 marcel@xcllnt.net