Friday, September 11, 2009
Building a virtual mesh potato, part 1
Hardware for the mesh potato has been delayed another month or so (and I can expect another month for delivery), and I'd planned on starting work on it in September, so I was stuck. I have plenty of things to do but my mindset had turned toward hacking... I also wanted to hack my existing router into better shape for ipv6. The two tasks are congruent as they use basically the same OS and toolchain, so I spent most of the last two days building up an environment to work on it, without the hardware.Enter qemu debian mips.
I spent a lot of time going down the wrong paths - for example it wasn't obvious to me that you needed an elf format kernel to run the thing. I also spent 24 hours of computer cycles trying to do debian install via the emulator, only to have the power fail 93% of the way through.
So, this morning, I downloaded a debian image for qemu mips. 24 minutes later I had a booting virtual mips box, emulating the MIPS to fool around in.
It Just Worked.
Embedded development just got a lot less hard. Flashing (and crashing) boards is a painful process easily avoided with an emulator. You can also do all sorts of robustness testing of the core software without fear of wrecking one of the precious few boards available, and you can work on "branches" of the core software by just keeping a couple copies of the emulator image around.
Heck, a good multi-core machine could probably emulate a dozen potatoes at the same time.
Once I get openwrt boostrapped onto it, it will let me fiddle with more modern kernels, alternate tools, and eventually the openwrt userspace that the mesh potato uses with well as the web interface, etc, long before the hardware is available.
I seriously doubt this is going to be fast enough to actually run the core voip software, but we'll see. The other core feature - mesh networking - may well be simulatable.
Maybe I can make a virtual box visible on the internet, too. That could help a lot of people.
My hat is off to the QEMU and Debian guys. You're awesome.
Back to hacking together a more modern kernel....
Labels: mesh potato
¶ 12:32 PM
