As mentioned, I am interested in diversifying my OS knowledge further. Joel mentioned he was teaching an RTEMS Open Class in Munich last month so that was a perfect opportunity to take part.
So I booked a flight, and AirBNB room, and there I was! Coffee, pretzels (I get it now!), class, beer, food, hacking - heavenly really. It was a great experience. For many reasons!
Reasons the class was great, one: I learned a lot about RTEMS
Both usage and its internal structure, and real-time systems in general. I had done some preparation beforehand so that I would get the most out of the class, but both were something of a first for me.
Pictured above: Joel in front of the projection screen.
Two: I got to socialize with Joel
He lives in the US so we don't see each other much. It was great to catch up a bit and talk about subjects ranging from technical RTEMS subjects, to life and happiness and such things in general.
Left: me. Right: Joel.
We all know socializing is simply code for drinking beer together, no?
Three: the Beagle BSP
Based on Joel's suggestion beforehand I had set myself the goal of writing a BSP for the Beagle family of products for RTEMS. In other words, a port of RTEMS to the beagles; specifically the BeagleBoard XM, BeagleBone 'White,' and the BeagleBone Black. Joel mentioned this at the start of the 4-day class to the other participants, so that raised the pressure to succeed within the class timeframe significantly!
I hacked on it as much as I could between classes and socializing and "on the last day" I got it working. I really enjoyed Joel demonstrating it to the rest of the class! We hooked up my laptop to the projector and went to town.
Pictured: Joel demonstrating RTEMS running on the Beaglebone Black that I brought with me.
And, also on the last day:
I got a certificate! It really did feel like going back to school and it was quite a nice experience.
Where to go
The Beagleboard XM RTEMS Wiki page contains something of a history of the RTEMS Beagleboard port.
Claas Ziemke started an RTEMS BSP for the original Beagleboard for a GSOC project, so he wrote the basis for that page.
Chris started the wonderfully-named section "Ben and Chris's Big Beagleboard Adventure" - I couldn't have phrased it better, that's really what it feels like! Also sounds a bit like "Bill and Ted" and I hope Chris meant it that way too.
The work-in-progress code is at my github RTEMS fork.
What next, and: foreshadowing
I'm really delighted with how far the BSP has come, as it's a first for me to do something with RTEMS, and indeed get any new OS working almost-from-scratch on a new piece of hardware. Well.. That's an exaggeration, as a lot of ARM support was already there. But still, filling in a few more basics can make it feel like it's from-scratch!
The Beagles are such nice products that it's a real PR opportunity for RTEMS too I believe, and I'm thrilled to be able to contribute that to RTEMS.
I have spent a lot of time since then running the full test suite, and cleaning up the BSP - mostly by minimizing it. Part of the effort to merge this BSP with mainline is that I am working with Chris to get the RTEMS executable running from scratch using JTAG. But that is a topic of another, similarly exciting, post.