>> In linux/arch/arm/mach-ep93xx/core.c EP93XX_TIMER1_LOAD is loaded with
>> "(508469 / HZ) - 1" to obtain a timer with the HZ frequency. Timer 1 is
>> running at 508 kHz so this seems strange. On the other hand HZ is 100 so the
>> last parts of the load-value is thrown away.
>
> well, it's not exactly 508 kHz as the docs claims, but it's 14.7456 Mhz
> divided by 29 = 508496. The timer is 16-bit only, you can't feed it with this
> value anyway.
>
>> Is there a reason for this?
>
> Yes, it's CONFIG_HZ value, it's a frequency of the timer interrupt, so if it's
> 100, it means, that it will be called 1/100 of second, or 10ms. So if you feed
> it with 508496 it will be called once a second, which is wrong since the timer
> interrupt is heart of the system. So the value 5083 is correct and means the
> timer interrupt is called 100 times per second, every 10ms.
Actually I found 5084 gives a better system clock. Using adjtimex and some
clockwatching allows one to have a system clock with an accuracy of about
2ppm (assuming a fairly constant environment). That's about 1 sec drift in
5 days.
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