[PATCH 5/5 v2] ARM: OMAP1: recalculate loops per jiffy after dpll1 reprogram

Russell King - ARM Linux linux at arm.linux.org.uk
Fri Dec 9 03:42:45 EST 2011


On Tue, Nov 29, 2011 at 01:25:32AM +0100, Janusz Krzysztofik wrote:
> However, the result of cpufreq_scale() differs from that of
> (re)calibrate_delay() by ca. 6%, i.e., 70.40 vs. 74.54. Please advise if
> this approximation is acceptable.

You don't say which figure is what.

Note that calibrate_delay() is itself inaccurate - the loops_per_jiffy
is the number of loops which can be executed between two timer ticks
_minus_ the time to process the timer interrupt itself.  So, it's
actually always a little less than the theoretical number of loops
within that time period.



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