Re: [uClinux-dev] Timekeeping problem: time runs too fast
On Wed, Apr 28, 2010 at 10:20:53AM +0200, Stephane Lambert wrote: > Hello all, > I'm working on the porting of uClinux 2.6.19 for a new architecture. Sorry, but why do you port an ancient version of Linux to a new architecture? Did you start four years ago?? > Does this timekeeping mechanism perfectly functionnal for this version > of the kernel? I don't know. I know for sure it did work in 2.6.27 and it definitely does work in 2.6.33. Daniel ___ uClinux-dev mailing list uClinux-dev@uclinux.org http://mailman.uclinux.org/mailman/listinfo/uclinux-dev This message was resent by uclinux-dev@uclinux.org To unsubscribe see: http://mailman.uclinux.org/mailman/options/uclinux-dev
Re: [uClinux-dev] Timekeeping problem: time runs too fast
> I have an other question concerning the macro CLOCK_TICK_RATE > (include/asm-'arch-name'/timex.h): > this macro seems to be architecture dependant. It's generally 1193180. > > What is this macro used for? For ntp-based time synchronisation. > What value should I give to it? CLOCK_TICK_RATE should give the underlying frequency of the tick timer. i.e. the frequency of the hardware input clock of your tick timer Philippe -- Philippe De Muyter phdm at macqel dot be Tel +32 27029044 Macq Electronique SA rue de l'Aeronef 2 B-1140 Bruxelles Fax +32 27029077 ___ uClinux-dev mailing list uClinux-dev@uclinux.org http://mailman.uclinux.org/mailman/listinfo/uclinux-dev This message was resent by uclinux-dev@uclinux.org To unsubscribe see: http://mailman.uclinux.org/mailman/options/uclinux-dev
[uClinux-dev] Timekeeping problem: time runs too fast
Hello all, I'm working on the porting of uClinux 2.6.19 for a new architecture. The system is booting without problems, but I have a problem concerning timekeeping. Indeed, the date command shows that time runs too fast (5 sec in reality for around 10 minutes in Linux...). So I have read documentation about timekeeping, the important things seems to be the following: - jiffies -> number of timer interrupts (ticks) since the system startup. - xtime.tv_sec -> number of seconds elapsed since Epoch (1970, jan 1 00:00:00) - xtime.tv_nsec -> number of nanoseconds elapsed during the current second. These variables are updated at each timer interrupts, notably in update_wall_time() where xtime fields are modified in an algorithm involving the kernel clock (clocksource). Does this timekeeping mechanism perfectly functionnal for this version of the kernel? I have an other question concerning the macro CLOCK_TICK_RATE (include/asm-'arch-name'/timex.h): this macro seems to be architecture dependant. It's generally 1193180. What is this macro used for? What value should I give to it? Thanks in advance for your help. Regards. ___ uClinux-dev mailing list uClinux-dev@uclinux.org http://mailman.uclinux.org/mailman/listinfo/uclinux-dev This message was resent by uclinux-dev@uclinux.org To unsubscribe see: http://mailman.uclinux.org/mailman/options/uclinux-dev
