[U-Boot] [PATCH 2/2] ep93xx: Refactoring of timer code

[Matthias Kaehlcke <matthias@kaehlcke.net>]

Hi Wolfgang,

El Tue, Feb 23, 2010 at 11:23:42PM +0100 Wolfgang Denk ha dit:

> In message <20100223220421.GK20201@darwin> you wrote:
> > ep93xx: Refactoring of the timer code, including the following changes
> ...
> > +#define TIMER_FREQ			508469
> > +#define CLK_TICKS_PER_SYS_TICK		(TIMER_FREQ / CONFIG_SYS_HZ)
> ...
> > +		ticks *= (CLK_TICKS_PER_SYS_TICK * CONFIG_SYS_HZ);
> ...
> > +		ticks = usecs * CLK_TICKS_PER_SYS_TICK * CONFIG_SYS_HZ;
> 
> Why don't you use
> 
> 	ticks *= TIMER_FREQ;
> resp.
> 	ticks = usecs * TIMER_FREQ;
> 
> The combination of " / CONFIG_SYS_HZ * CONFIG_SYS_HZ" is just a bad
> NO-OP (with rounding errors).

you certainly have a point, i'm going to change this as you proposed

> Hm... re-reading the optimized code makes me wonder if the variable
> really should be called "ticks" - looks more as a frequency to me?

here i disagree, the function returns the number of ticks that pass in
a certain number of microseconds, so i think 'ticks' is an appropiate
name

thanks for your review!

-- 
Matthias Kaehlcke
Embedded Linux Developer
Barcelona

        I cannot say whether things will get better if we change,
      what I can say is they must change if they are to get better
                   (Georg Christoph Lichtenberg)
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