Re: [ath9k-devel] [PATCH 1/3] ath9k: Fix build error on ARM

[Joe Perches <joe@perches.com>]

On Wed, 2014-02-05 at 11:50 +0000, Russell King - ARM Linux wrote:
> On Tue, Feb 04, 2014 at 08:36:36AM -0800, Joe Perches wrote:
> > On Tue, 2014-02-04 at 08:03 +0100, Holger Schurig wrote:
> > > Joe, look in linux/arch/arm/include/asm/delay.h. The macro udelay
> > > cannot handle large values because of lost-of-precision.
> > > 
> > > IMHO udelay on ARM is broken, because it also cannot work with fast
> > > ARM processors (where bogomips >= 3355, which is in sight now). It's
> > > just not broken enought that someone did something against it ...   so
> > > the current kludge is good enought.
> > 
> > Maybe something like this would be better?
> 
> No, the point of __bad_udelay() is that people doing stupidly large
> udelay()s result in build errors,

Apparently, people just convert stupidly large udelay()s
to mdelay and not be bothered.

>  rather than having to run the kernel
> and trip over a non-existent debugging message beacuse they haven't
> built the kernel with DEBUG defined.
> 
> NAK.

<shrug>

Perhaps there should be some runtime udelay > maximum
supported check.