Timers on mpc8248 etc...

Scott Wood scottwood at freescale.com
Thu Nov 29 10:43:17 EST 2007


Alan Bennett wrote:
> I've got a routine that needs to delay for X microseconds, this is a
> must.  The command after schedule_timeout must has to wait for the HW
> to complete a task that takes X microseconds.
> 
> I would think that one way to do this is with a simple
> schedule_timeout.  But in the example below, the time that passes from
> run1() to dontrun() is far less than 3.2 msecs.  Infact, sometimes its
> ~ 800 micros according the a analyzer looking at points triggered in
> run1() and donrun().  Could this be a configuration problem with the
> timer/interrupt that generates the jiffies?

Are you sure the timebase frequency is set correctly in the device tree?

-Scott



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