On Thu, 2007-09-20 at 10:52 +1000, Paul Mackerras wrote: > Daniel Walker writes: > > > If you switch to the rtc do the shift and mult need to change? > > You can't switch; any given CPU chip will have either the RTC or the > timebase but not both. The code is switching between to clock read functions .. If they are running at different frequencies then the time isn't going to be converted to nanosecond properly. So is the rtc running at the same frequency as the timebase? I'd guess no.. > > > + /* XXX this assumes clock->shift == 22 */ > > > + /* 4611686018 ~= 2^(20+64-22) / 1e9 */ > > > + t2x = (u64) clock->mult * 4611686018ULL; > > > > It might make the code more readable if you put that constant into a > > macro that gives it a name. > > The comment already gives more information than some arbitrary name > would. I'm not a powerpc expect, but I have no idea what that constant is.. Daniel - To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
