From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262178AbULMAPj (ORCPT ); Sun, 12 Dec 2004 19:15:39 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262177AbULMAPj (ORCPT ); Sun, 12 Dec 2004 19:15:39 -0500 Received: from fw.osdl.org ([65.172.181.6]:4839 "EHLO mail.osdl.org") by vger.kernel.org with ESMTP id S262178AbULMAPc (ORCPT ); Sun, 12 Dec 2004 19:15:32 -0500 Message-ID: <41BCDE26.9030309@osdl.org> Date: Sun, 12 Dec 2004 16:11:18 -0800 From: "Randy.Dunlap" User-Agent: Mozilla Thunderbird 0.9 (X11/20041103) X-Accept-Language: en-us, en MIME-Version: 1.0 To: gene.heskett@verizon.net CC: linux-kernel@vger.kernel.org Subject: Re: dummy help on io References: <200412121854.48898.gene.heskett@verizon.net> In-Reply-To: <200412121854.48898.gene.heskett@verizon.net> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Gene Heskett wrote: > Greetings; > > I've ordered the device drivers book from O-Reilly but it will be > a few days getting here. Get it online: http://lwn.net/Kernel/LDD2/ > I'm trying to mod the GPL'd archive PIO.tar.gz, so it will build a > driver for a pci card with 3 each 82C55's on it, and I *think* I'd > have it working with the first of the 3 chips if I could figure > out what to do about using the call "iopl(3);" on installing > the driver, and conversely an "iopl(0);" at rmmod time. Where is that coming from? I don't see it in the tarball or the web site (if I'm looking at the right place). http://ieee.uow.edu.au/~daniel/software/robotd/ > I'm told this is required to gain access perms to addresses above > 0x3FF. The call "ioperm" is used below that I've been told. iopl() and ioperm() are userspace calls that call (g)libc. The kernel doesn't call them. > Unforch, an "insmod PIO io=0xf100" (where the card is addressed > at currently) is spitting out an "unresolved symbol" error for the > iopl call. > > Being a rank beginner at "pc" hardware, can someone give me a > checklist of things I've probably left out please? Can you put the iopl() call into your app instead? or into a shell script that forks the app (since the iopl man page says: Permissions are inherited by fork and exec.) > Kernel is 2.4.25-adeos. With the module "rtai" inserted when emc > is running for realtime control purposes. > > The card is pure hardware, no bios, only address decoding that > can set the base address anyplace in the first 64k of address > space in a step of 4 sequence from 0xnn00-0xnn0C for the 4 > ports of chip 1, 0xnn10-1C for chip 2, etc, where the nn is the > dipswitch setting. -- ~Randy