[ECOS] FOSDEM 2003 report

Jonathan Larmour jifl@eCosCentric.com
Fri Mar 21 02:18:00 GMT 2003


Long long overdue! But since I made notes, I may as well transcribe them...

Overall FOSDEM 2003 was surprisingly well attended (compared to what I 
admit I was expecting!), including the embedded track - sometimes up to 
about 50 people. Of course the keynote speakers... Jon maddog Hall and 
Richard Stallman got a packed crowd, but the ULB (Université Libre de 
Bruxelles) had plenty of capacity.

There were various interesting presentations of course, not just the 
eCos-y bits :-). There was one on OpenRISC, which in fact we've just 
received a port for.

There was also one on Wonka, a free JVM, that has been ported to eCos. 
Time permitting someone (worst case me, but volunteers welcome!) should 
take that under their wing, bring it up to scratch, and include it in 
eCos. Chris Gray of Acunia  (chris.gray [at] acunia.com) mentioned it's 
suffered bit-rot. An initial investigation on my part shows that 
integrating it into our build system could be amusing. Of course we should 
also consider GCJ support too eventually.

Then of course there was the inspired talk given by Nick G on eCos :-). 
You can get the presentation at 
<http://www.ecoscentric.com/fosdem2003/about.html> although of course much 
was fleshed out at the time. Again it was well attended.

Immediately afterwards there was an informal meeting about eCos during 
lunch. It was even more anarchic than I expected, oh well :-). There were 
all sorts of things discussed there. A few highlights were:

- Some example applications eCos is being used in, such as:
    * Bob Koninckx (Hi Bob!) doing something with 5 CPUs in a false leg?!
    * Payment systems
    * Ground based satellite control systems
    * More that I didn't write down at the time :-|

- Features most wanted:
   * testing is a "must-have". So things to make testing easier for people 
who want to do it. I also know that eCosCentric is going to be trying to 
make public as much as possible of its Test Farm results

   * Memory Layout Tool in the v2 Config Tool

   * Debugging support in RedBoot, i.e. the ability, from the RedBoot 
prompt, to do things like exitting back to the ROM monitor prompt (with 
Ctrl-c, a physical button on a board, soft magic in the application or 
whatever), breakpoints, stepping, etc. I know Cygmon used to have these 
(plus a simple non-GPL disassembler for x86 and some other arch), and of 
course "competing" ROM monitors also do.

   * bridge + SNMP support in the FreeBSD stack so we can drop the OpenBSD 
stack. Andrew L has bravely done the latter now.

   * A shell! This has come up before and we kept telling people it's 
inappropriate without processes, safe thread control (can you _really_ 
just suspend/restart threads?), and frequently no filesystem. But people 
said we should consider it as infrastructure so that _they_ can add shell 
stuff that they want to.

Someone mentioned dash as a starting point... see 
<http://v2dash.hypermart.net/>... but looking at it that can't have been 
right. More relevant may be that it gives an idea of the commands a custom 
shell we supplied _could_ provide.

A second but much more interesting idea IMO is to port TCLSH! That would 
be very powerful, it's very portable, was even originally designed for an 
embedded system. I like this idea a lot. It probably came from Bart of 
course ;-) although I can't remember for sure.

   * Dynamic loading. A full blown implementation is of course quite large 
and a can of worms. So two possibilities were suggested - a system similar 
to what vxWorks does where objects are linked but still with relocs 
(essentially a .o file) and linking at the time the .o is loaded by 
comparing with a built-in symbol table and filling in the relocs (and 
adding newly exported symbols from the new object to the symbol table 
too). Presumably some sort of init function with a unique name to that 
object would want to be called too.

   A second possibility (and it isn't either/or - both are possible) would 
be a very simple system using function pointer tables and stubs - for 
those who just want dynamically updatable code rather than more complex 
dynamic loading.

   * eCos under Linux in a similar way to RTLinux, or more interestingly, 
Adeos... see <http://www.nongnu.org/adeos/>. For that matter, presumably 
it would be possible to port eCos *to* the Adeos nanokernel allowing 
co-existence with Linux.

   * We should have a list of Unique Selling Points somewhere (web, 
documentation, whatever) of RedBoot *versus* other ROM monitors. Paging 
Gary Thomas.... Gary Thomas to the white courtesy phone...

   * I've written down that someone said they wanted Ada?! Must have been 
hearing things ;).

People also discussed licensing, and the only notable conclusion was that 
with eCos's GPL exception clause, there *isn't* really a demand for a 
proprietary variant of the eCos licence. The existing licence is good enough.

I also attended some talks about wxWindows with Julian Smart (who wrote 
the eCos Configtool v2). Now there has been a long-standing debate about 
the best route for host side GUI implementation. It was decided ages ago 
finally to solve this with wxWindows, hence the config tool v2 uses that.

However I know Bart has plans to try and do more TCL/Tk things, 
particularly given the future requirements of CDL scripts. However pretty 
much everyone else doesn't like the non-native look-and-feel of TK 
widgets. Julian's presentation made me think that perhaps the best route 
might be wxTCL. See <http://membres.lycos.fr/awaken/>, although this isn't 
yet complete. But with a wxTCL I think everyone would be happy.

Finally, the maintainers who attended... myself, Bart, Nick and Andrew (as 
well as Alex Schuilenburg (not a maintainer)) went to dinner in a nice 
Chinese restaurant, and Alex took this picture: 
<http://www.ecoscentric.com/fosdem2003/dinner.html>

That's it! Perhaps I should enter some of the ideas above as enhancement 
requests in bugzilla, but it's probably not worth it.

All in all a good event, and worth the entrance fee ;-).

Jifl
-- 
eCosCentric    http://www.eCosCentric.com/    The eCos and RedBoot experts
--[ "You can complain because roses have thorns, or you ]--
--[  can rejoice because thorns have roses." -Lincoln   ]-- Opinions==mine


-- 
Before posting, please read the FAQ: http://sources.redhat.com/fom/ecos
and search the list archive: http://sources.redhat.com/ml/ecos-discuss



More information about the Ecos-discuss mailing list