I'm confused by the "watchdog tickle chain"

[Phil Torre]

On Thu, Mar 21, 2002 at 04:27:58PM -0600, Eric Norum wrote:
>
> The delta_interval in the watchdog chain is the number of ticks to wait 
> *relative to the previous entry*.  Thus decrementing the ticks of the 
> first element on the chain effectively decrements the ticks of all 
> elements on the chain.  The cost, of course, is the time taken to walk 
> the queue when inserting an element (see the code for _Watchdog_Insert), 
> but this presumably happens a lot less often than _Watchdog_Tickle().

Oooh, that's one of those messages I wish I could've pulled back about
a minute after sending it...

That's of course correct, and my bug is being caused by the PIT interrupt
nesting into itself and decrementing the delta *twice* before testing it.
I need to turn MSR[EE] back on so a higher priority interrupt can run,
but I'm not masking the PIT first.  D'oh!

-- 

=====================================================================
Phil Torre                               phone: 425-820-6363 x234
Design Engineer                          email: ptorre at zetron.com
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