From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261662AbUKCQNh (ORCPT ); Wed, 3 Nov 2004 11:13:37 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261669AbUKCQNh (ORCPT ); Wed, 3 Nov 2004 11:13:37 -0500 Received: from ltgp.iram.es ([150.214.224.138]:37763 "EHLO ltgp.iram.es") by vger.kernel.org with ESMTP id S261662AbUKCQNb (ORCPT ); Wed, 3 Nov 2004 11:13:31 -0500 From: Gabriel Paubert Date: Wed, 3 Nov 2004 17:13:04 +0100 To: "H. Wiese" <7.e.Q@syncro-community.de> Cc: Linux Kernel Mailing List Subject: Re: IP Layer on VME-Bus Message-ID: <20041103161304.GB8075@iram.es> References: <33093.192.35.17.30.1099489553.squirrel@config.hostunreachable.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <33093.192.35.17.30.1099489553.squirrel@config.hostunreachable.de> User-Agent: Mutt/1.5.6+20040907i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Nov 03, 2004 at 02:45:53PM +0100, H. Wiese wrote: > Hello, > > we develop a driver which enables us to use an ip layer on top of the vme-bus > technology. Now we got some problems with coding the driver. We already have > an old version of this driver (called "dpn") which works well but has no use > for us anymore since we upgraded our system from kernel 2.2.14 to 2.6.7. So > now we have to create a new driver. > > The old driver established the ip layer by accessing the dual port ram of > the VME bus, which is based on a Tundra Universe II Chipset. This enables > us to transfer data, ping etc. between active VME-modules using the > VME-bus. Very useful. Which Universe driver did you use? There are several floating around, mine among them. I plan to port it to 2.6, time permitting but I'm a bit worried by the size of the kernel these days. I have to run diskless systems with 16MB of RAM, my 2.2 kernels are about 800kB while the 2.6 kernels on my Mac are in the 5MB or more range. Even after removing USB, ext3 and a few other things, the 2.6.x kernel will be at least twice the size of the 2.2 series it seems. With my Universe driver or anything derived from it, the thing to watch out for is the PCI memory space allocation, 2.2 simply did not have the support (it mostly used the thing as the BIOS/firmware had configures it) and the Universe is a PCI mmio space hog with base registers outside the standard PCI header space (there are valid reasons for both of these characteristics). > Well, the problem we will surely run into is: will the driver work as fine as > the old one if we only recreate the initialization functions working with the > new kernel function set (e.g. wait_event_interruptible instead of > interruptible_sleep_on etc.), copy the essential functions from the old > driver > to the new one and alter them a little to work with the new kernel functions? I'm already using wait_event_ and friends in my 2.2 drivers, you should select a better example ;-) Regards, Gabriel