I'm looking for a TCP/IP stack that can be used without an OS. Our customer has an "aversion" to interrupts and doesn't want a real OS on a embedded board we're building. It's desirable to move as much of the functionality to FPGA as possible due to the fact we will be only using a 50 to 100 MHz Arm. And I'm pretty sure GPL licensed stuff won't be acceptable for this client. (Due to the legal quagmire associated with it. They expect to have full unrestricted rights to the software once it's complete.)
+2
A:
This doesn't necessarily answer your question the way you want it answered (it's not in the comments section since my diatribe is probably going to be too long). However, I think it may still be helpful.
A couple of points. I think you should re-educate your clients on the benefits and costs of interrupts. Interrupts are a very efficient way of handling device control and, unless you're meticulous about your coding, you're unlikely to match the performance with non-interrupt-driven code.
Secondly, using GPL software will give them full unrestricted rights to the software, it just won't allow them to restrict others. If you mean they do want to restrict others then I'd be asking why they think they should have the right to use the labours of others without any give-back.
You may well be able to find a TCP stack under a more permissive licence than GPL (allowing them to effectively close-source it). If you have a C compiler for your FPGA, you can possibly look into uIP which has a very permissive licence from a brief look:
Copyright (c) 2001-2006, Adam Dunkels and the Swedish Institute of Computer Science
All rights reserved.
Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
The name of the author may not be used to endorse or promote products derived from this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE AUTHOR `AS IS' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
That's it, no "must release under GPL" or any other viral clauses, and the only attribution is the inclusion of the copyright notice.
paxdiablo
2010-07-12 13:26:23
I've tried to use interupts in the past, but it violates a governing spec that they invoke for all systems. Basically performance be damned, if there is ANY way to meet the requirements of the system without using interrupts then thou shalt not use interupts. As far as GPL, they will NEVER disclose any source code to the public, therefore no GPL. How complete of an implementation is uIP?
NoMoreZealots
2010-07-12 13:55:06
I think that is a crappy license - what does "binary form" mean.? Does that mean in an embedded system you must burn the text of the license into ROM? This is what happens when people write their own licenses - they make their software impossible to use.
anon
2010-07-12 21:09:08
@Neil, normally I would read that as just putting the licence text into your documentation somewhere ("... in the documentation and/or ..."). A certain large nameless company do a similar thing with their use of third-party products - they have their own licence in the doco and they also state that other software is used, putting all those other licenses in there as well. As far as how crappy it is, it's certainly easier to understand and comply with than the GPL - only three clauses to worry about.
paxdiablo
2010-07-12 23:58:18
This is a BSD license with the author, organization and year changed to reflect who the author and organization are and the years the materials are copyrighted. (http://www.opensource.org/licenses/bsd-license.php)
Michael Burr
2010-07-13 18:20:31
+8
A:
uIP (micro IP) and lwIP (lightweight IP) are both candidates worth consideration. According to the original developer of both stacks - Adam Dunkel - one of the primary differences between the two is: "lwIP is larger than uIP, but provides better throughput". Both stacks employ a modified BSD license and have been used in commercial products.
Brandon E Taylor
2010-07-12 20:57:40
We have used both uIP and lwIP with great success, both without an OS. I would highly recommend either. If you have the room, lwIP seems to do less "magic" and is easier to understand. However, uIP seems to be better supported recently.
Kyle Heironimus
2010-07-13 13:50:30
A:
Currently I'm using the lwIP library on an ARM Cortex-M3 at 50MHz with no OS. It's a project based on the Luminary Micro (now TI) Stellaris Serial to Ethernet Reference Design Kit (http://www.luminarymicro.com/products/rdk-s2e.html).
This kit includes source code and schematics and gives us a solid base to develops some products.
I've no affiliation with TI or Luminary, just a very happy customer.
PFM
2010-07-16 07:34:23