[RFC/RFT 1/3] iop: clocksource support

[Linus Walleij]

2009/9/1 Mikael Pettersson <mikpe at it.uu.se>:

>  > Calculate this using the algorithm in arch/mips/kernel/time.c
>  > they have a dynamically changing clocksource...
>
> The algorithm always computes the largest shift/mult pair that
> solves the equation:
>
>        // 0 <= shift && shift <= 32
>        u64 mult = ((u64)1E9 << shift) / hz;
>        (mult >> 32) == 0
>
> Can I assume that this is to minimize precision loss?

So I think, I asked the question of how to calculate div but noone
answered IIRC, then I found the MIPS code and it contained this
clue. Ralf Baechle from the MIPS camp wrote this code so lets
ask him.

Linus Walleij