Playing with pandas
For the last few days I’ve been experimenting with getting a Pandaboard running Android 4.0, continuing the work that Clint Talbert started in the fall to get these boards for use as a replacement for the Tegra in Mozilla’s android automation. The first objective is to get a reproducible build going, after that we’ll try to get some of our custom tools (SUTAgent & friends) installed by default.
So far this has been… interesting. Much as Clint did before, I thought I’d document some of the notes on what I did in the hopes that they’ll be helpful to other people trying to do similar things.
Getting things up and running is a two step process. First, you build the beast. This part is straightforward, just follow the instructions here:
At least the build part is more or less straightforward. Just follow the instructions here:
Note that you almost certainly want to build in the “eng” configuration, which is rooted and (apparently) has some extra tools installed.
Installing it is a little more tricky. The way they want you to do this is put the pandaboard into a special mode and copy the stuff you built onto an sdcard. Seem a little funny to you? Yeah, it does to me too. Why not just build an sdcard image directly?
Nonetheless, this is the officially supported way of imaging a pandaboard, so let’s just follow it until we can think of a better way of doing things. The instructions for doing this on the pandaboard are located in the source tree here:
These are mostly correct as far as I can tell, but there’s a few gotchas. First, you need to run the commands mentioned as root unless you’ve configured USB to be configurable by your user. Second, most of those commands are not in the path by default so you’ll need to specify the full path to e.g. the fastboot utility. The instructions here cover these exception cases: I recommend following them instead.
One thing which neither document mentions is that you really need to make sure your sdcard is wiped completely clean before using fastboot. The “oem format” step only recreates the partition table, it doesn’t delete any corrupted partitions. If you reboot while these are still in place, it will try to bring up your corrupted version of Android, not the fastboot console. I spent quite some time debugging why I couldn’t properly flash the operating system before realizing this. Easiest way to get around this is to dd
/dev/zero onto the sdcard before beginning the flashing process.
Also, while not strictly necessary to get something up and running, I recommend highly getting an HDMI monitor as well as a serialUSB adapter. The former is useful to see if your Android device actually successfully booted up, the latter is useful for debugging boot issues where you don’t get that far (the serial console is always available from boot).
So, after painfully learning about the above caveats, I have managed to get things mostly working. I can see the ICS homescreen on my attached HDMI monitor and interact with it if I attach a USB mouse. The one gotcha is that both ethernet and WIFI networking are totally broken. Plugging in an ethernet cable or connecting to a WIFI network seems to result in the machine randomly rebooting, with the logs saying nothing useful. Both of these things are ostensibly supposed to be working according to the latest I’ve read from Google so I’m not exactly sure what’s going on. Investigations will continue.