When the timestamp is incremented via interrupt and the interrupt
period is greater than 1 msec, successive calls to get_timer() can
produce inaccurate timing since the interrupts are asynchronous
to the timing loop. For example, with an interrupt period of 10 msec
two successive calls to get_timer() could indicate an elapsed time
of 10 msec after only several hundred usecs -- depending on when
the next interrupt actually occurs. This behavior can cause
reliability issues with components such as CFI and NAND.
This can be remedied by calling reset_timer() prior to establishing
the base timestamp with get_timer(0), provided reset_timer()
resets the hardware timer (rather than simply resetting only the
timestamp). This has the effect of synchronizing the interrupts
(and the advance of the timestamp) with the timing loop.
Signed-off-by: Scott McNutt <smcnutt@psyent.com>
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