From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from nz-out-0506.google.com (nz-out-0506.google.com [64.233.162.237]) by ozlabs.org (Postfix) with ESMTP id C558EDE1E4 for ; Wed, 30 May 2007 04:25:24 +1000 (EST) Received: by nz-out-0506.google.com with SMTP id v1so1646835nzb for ; Tue, 29 May 2007 11:25:23 -0700 (PDT) Message-ID: Date: Tue, 29 May 2007 12:25:22 -0600 From: "Grant Likely" Sender: glikely@secretlab.ca To: "David Hawkins" Subject: Re: pcimsg patch from eons ago In-Reply-To: <465C6596.4030208@ovro.caltech.edu> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed References: <465C6596.4030208@ovro.caltech.edu> Cc: Behan Webster , Linux PPC List-Id: Linux on Embedded PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 5/29/07, David Hawkins wrote: > Hey Grant, > > TCP/IP over PCI is also something I want to look into. > I'll have about 8 compact PCI crates, with 15 MPC8349E boards > in each that I will boot with U-Boot, and then TFTP a kernel, > and then NFS mounted filesystem on. I'll put ethernet on > the front-panels for the prototype boards, but ideally > I want TCP/IP over PCI for the final system. > > The board support package for the Freescale MPC8349E-MDS-PB > has some sort of support for this, but I haven't had a look > at the code yet. Cool, I'm not actually going to be using PCI on this project, but it is a shared memory system, and so I expect the bulk of the protocol could be similar. The system I'm working on consists of a DSP and an MPC8349 connected via 128K of shared ram. I need to put together a low level protocol which will support multiple interfaces on top of it, and I figured that the old IP-over-PCI would be good place to start. I need to layer console and filesystem interfaces on top to begin with, and then additional interfaces as the product matures. > > I'm pretty sure Dan Malek had written something similar for > TCP/IP over RapidIO. Take a look in the kernel source, > I forget the name ... I have some notes around here somewhere ... Hmm, yes I hadn't thought of looking at RapidIO. If the low level protocol was a straight forward message passing interface, then the stuff on top could potentially be the same. > > I'm working on hardware at the moment, so my software > brain cells are lying dormant. Let me know if you want > me to dig up the Freescale stuff and I'll send it to you, > or send you a link to a copy of the ISO. Downloading the > BSP from Freescale's site is a nightmare. I can also > plug the MDS board in as a peripheral and fire up their > TCP/IP over PCI and see what works. Yes, please send me whatever you have. > It really shouldn't be too much trouble to get working. > I started by looking at the PLIP code just to see what > that took, and its pretty short. The most work would > be in defining infrastructure to make adding DMA of > data between the host CPU and the peripherals flexible. > Most (all?) x86 hosts don't have DMA, so both write and > read would be handled by the peripheral board. However, > for PPC hosts with DMA, then writes should be handled > by the respective boards ... I'm not sure what the > easiest way to deal with that would be. > > Feel free to start a discussion on this :) > > Cheers, > Dave > -- Grant Likely, B.Sc., P.Eng. Secret Lab Technologies Ltd. grant.likely@secretlab.ca (403) 399-0195