From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Fri, 17 Nov 2000 12:34:12 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Fri, 17 Nov 2000 12:34:02 -0500 Received: from panic.ohr.gatech.edu ([130.207.47.194]:2314 "EHLO havoc.gtf.org") by vger.kernel.org with ESMTP id ; Fri, 17 Nov 2000 12:33:54 -0500 Message-ID: <3A1564D9.2AC70F6F@mandrakesoft.com> Date: Fri, 17 Nov 2000 12:03:21 -0500 From: Jeff Garzik Organization: MandrakeSoft X-Mailer: Mozilla 4.75 [en] (X11; U; Linux 2.4.0-test11 i686) X-Accept-Language: en MIME-Version: 1.0 To: Russell King CC: linux-kernel@vger.kernel.org, mj@suse.cz Subject: Re: VGA PCI IO port reservations In-Reply-To: <200011171658.QAA01331@raistlin.arm.linux.org.uk> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Russell King wrote: > Jeff Garzik writes: > > If XFree86 not fbdev is using the hardware, you can always have a stub > > driver that does nothing but reserve the ports. Remember, too, that the > > ports claimed depend on register settings in the video card and PCI > > config space.. > > I wish. Unfortunately, ones of this nature tend to be rather fixed. No amount > of config space twiddling will move them. However, as someone else pointed out, > x86 gets around this problem by only allowing IO ports to be allocated in the > (addr & 0x0300) == 0 range, thereby avoiding the problem. Dig through the video card docs, even older ISA video cards let you disable I/O decoding on all but a few ports, and/or relocate the ports it does use to other areas. Different with every video card, of course, but most of them can do this to a greater or lesser extent. Jeff -- Jeff Garzik | Building 1024 | The chief enemy of creativity is "good" sense MandrakeSoft | -- Picasso - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/