BeagleBoard keeps hanging

I know this is the worst possible bug report, because I don’t know how to reproduce the symptoms…

My BeagleBoard (rev. C4) keeps hanging, apparently randomly. When it does, the mouse cursor and the keyboard NumLock still work, but Alt-Break doesn’t. Sometimes it will hang as early as “No keyboard – autobooting”; other times it will hang at some point when invoking or using an application. Sometimes it boots as far as the RO splash, but with an hourglass that never goes away. The only other oddity I can think to note is that Control-Break seems to bring up the window that Alt-Break should, though always after a significant delay. (Perhaps I have always pressed Alt-Break before.)

At other times, it will run happily for hours.

So there are two things I’m asking:

1) Does anyone else see this happen?

2) How can I go about diagnosing the fault?

There’s some code in the HAL that can help track down issues like this. Go to Sources.HAL.OMAP3.s.Boot and set FIQDebug to TRUE, then issue the magic SWI SYS "OS_Hardware",123,,,,,,,,0,100 after booting the machine. Then you should find that pressing the beagleboard’s USER button prints out the PC to the serial port. So wait for the machine to lock up, then hit the USER button a few times to get an idea of where it’s getting stuck.

I recently noticed that Control-Break doesn’t always work, and can sometimes hang the machine. Something for me to look into, I guess. Also a while ago I found that I should be doing ISB/DSB operations after most/all cache maintenance operations, which the code currently doesn’t do, so it’s possible you’re seeing problems because of that (although I would have expected it to crash outright rather than get stuck in a loop). I’ll try and get this fixed sometime this week.