On Mon, 2007-10-15 at 11:49 -0500, Rune Torgersen wrote: > > The main couse is that our main bus frequency cannort be divided into > 1kHz evently by the decrementer. > Main bus freq = 99532800 Hz. > Decrementer then becomes 24883, which gives us 999991.9624485600nsec > per > jiffy. > That is not a number easilly converted into time without drift. > > Changing HZ to 100 fixes it, but is for varous reasons not an option > right now. > > What I did do is change the timer interrupt to be called by an > ecxternal > 1kHz interrupt source instead of the decrementer. > > The TB register is only ued for offsets from the last jiffie, not as a > continous offset, so then it works out pretty good. > There is a discontinuity in the sub ms resolution of the clock that I > can live with. msec and up are dead accurate.
The date is derived from the absolute TB value though... Ben. _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev