On Thu, Oct 10, 2013 at 12:31 PM, Davide Rossi <[email protected]> wrote: > Hi Julius, > > We are definitively interested in using the gcc regression test for a > functional verification of evoultions of the processor as you suggested > during the OpenRISC conference. > Could you provide some details about how test is performed on the or1200 or > mor1kx and/or a link to a document online explaining the procedure? > > I put also Michael Gautschi, who is the person who has actually done the > work on the OR1200 I've presented at during the OpenRISC conference.
Hi guys, Very good to meet you at ORCONF on the weekend Davide. We were very interested to hear about your work, it seems you have achieved an appreciable improvement of the OR1200's performance, and it'd be great if you could keep the community in the loop with any future developments. We'd very much like to see the patches for the work you've done so far. As I was asking when we spoke, I'm interested to know your verification plan for the CPU. It's something the project struggles with in general, and it'd be great to get more people thinking about this. The approach so far has been to write some directed tests (in C and assembly, some in Verilog to test debug features) and see if Linux works. Some useful additional test stimulus can be found in the GCC C test suite. We compile each of the tests against the bare-metal newlib library and launch them in the sim (usually on a cycle-accurate model generated by Verilator as that runs 100s of times faster than Icarus). Obviously this assumes the compiler is fine and any bugs will be the RTL's fault, which has been the case so far. We can compare the results of the GCC regression suite run against the RTL model with the results from running against or1ksim. They should, ideally, be identical. This process is not documented, but in the mor1kx-dev-env environment (on my github, it's a fork of orpsocv2 and I would advise against using it for development - efforts should be focused elsewhere such as ORPSoCv3 and a unified test suite) I have a script which allows you to point to the GCC source directory, and it will compile each of the tests and run them. https://github.com/juliusbaxter/mor1kx-dev-env/blob/master/scripts/make/Makefile-gccregression.inc It's far from the best way to do it, and it's not quite running it the way the scripts in GCC run it, but it's better than nothing. As I mentioned earlier, we'd really like a unified test case project to be developed, combining the C and assembly tests from or1ksim, ORPSoCv2 and the new ones which have been developed in mor1kx-dev-env. But that's in the works (perhaps something I'll get to hack on soon, we've been talking about it for years, so it's about time we do something on it). So I hope this is useful to you. Let me know if you have any other questions. And don't forget we're in #openrisc on irc.freenode.net if you'd like to continue discussions there. I'm CC'ing the mailing lists as I think this is useful information to have on the record. Cheers Julius _______________________________________________ OpenRISC mailing list [email protected] http://lists.openrisc.net/listinfo/openrisc
