[SPARCbook] 3GX: Reboot wedged at 0C0

[Greg]

>  |>Every now and then
>  |>it will beep, flash a 'Watchdog reset' message and run through
>  |>the sequence again.
> I er...removed the annoying speaker, so mine doesn't beep.
> However, I don't see the Watchdog reset message, nor does mine "restart." 
> 
> The watchdog timer is a counter (in the NVRAM?) that the OS (PROM? OS low level interrupt handler?) tracks.

That's a watchdog timer but it's not a Watchdog Reset nor do most Sun-based
machines have watchdog timers.  There is a kernel debugging feature that
acts sort of like one but it's not normally enabled.

A Watchdog Reset on SPARC processors happens when a trap occurs when traps
are disabled. The amount of code that runs with traps disabled tends to be
small and the code tends to be well-debugged.  So a watchdog reset,
especially one that happens before the kernel is loaded, is most likely due
to flaky hardware.  Watchdog Resets can also be caused by software bugs so
if they start happening after the kernel has been changed (patches, new
drivers, etc.) then you need to suspect the kernel as well.

Cheers!greg