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SubjectHPET drift question
Hi Venki,

I'm confused by the calculation of the drift value in the hpet
driver. The specs defines the recommended minimum hardware
implementation is a frequency drift of 0.05% or 500ppm. However, the
drift passed in when registering with the time interpolator is:

ti->drift = ti->frequency * HPET_DRIFT / 1000000;

Isn't that absolute number of ticks per second drift? The time
interpolator defines the drift in parts per million. Shouldn't this
simply be:

ti->drift = HPET_DRIFT;

The current code seems to greatly penalize any hpet timer with greater
than a 1MHz frequency. Thanks,


Alex Williamson HP Linux & Open Source Lab

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