[ELDK] Bogomips difference between 2.6.25 and 2.6.30

[Wolfgang Denk]

Dear "Philippe Villet",

In message <F9D1A9212590B640B744B50EF9E01686044E1515 at ENIEXCH01.ds.jdsu.net> you wrote:
> 
> If I force the timer clock to be CPU clock (By setting the 3 parameter to zero) :
> ibm440ep_fixup_clocks(sysclk, 0, 0);
> I get ;
> Calibrating delay loop... 790.52 BogoMIPS (lpj=1581056)
> In this case I confirm that :
> timebase = clock = bogomips / 2

OK.

> But I want to use the TMRCLK input clock (25MHz on my custom board), so I wrote :
> ibm440ep_fixup_clocks(sysclk, 0, 25000000);
> and got :
> Calibrating delay loop... 49.92 BogoMIPS (lpj=99840)

...which is approximately 2 x 25.

> I've checked the timebase_period_ns variable defined in devtree.c,
> generic_calibrate_decr function in time.c and everything seems correct.

And performance is ok, too?

> Any idea?

Well, remember the "bogo" part in bogomips; it's just a calibration
parameter, _not_ a performance measurement.  If your performance is
OK, and no other problems are observed, I would not worry about that.

Best regards,

Wolfgang Denk

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