[U-Boot-Users] when to call the WATCHDOG_RESET()

Wolfgang Denk wd at denx.de
Mon Nov 1 21:36:17 CET 2004


In message <3D9FDCA910DD4445896A0BE5ECF009D4017EB335 at bla.satyam.com> you wrote:
>
> In my device initialization and other routines, how do I decide exactly when
> to call WATCHDOG_RESET ()?

Estimate the time needed to run your code, and look  up  the  minimum
watchdog  trigger  time  in  your  hardware specs. Than make sure you
trigger the WD often enough.

Usually, there only few places where this is  critical  -  check  for
those  parts  of  the code before the timer interrupt is running, and
after  it  for  parts  where  interrupts  get  disabled  (like   when
uncompressing a Linux kernel image).

Most systems behave harmless, but there are a few nasty ones like the
LWMON board with a watchdog that needs triggering after a maximum  of
80 millisec...

Best regards,

Wolfgang Denk

-- 
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