lkml.org 
[lkml]   [2007]   [Dec]   [15]   [last100]   RSS Feed
Views: [more markup]  [less markup]  [headers]  [forward] 
 
Messages in this thread
/
DateSat, 15 Dec 2007 23:59:43 +0100
FromPavel Machek <>
SubjectRe: [PATCH] x86_64: fix problems due to use of "outb" to port 80 on some AMD64x2 laptops, etc.
On Fri 2007-12-14 15:23:55, Ingo Molnar wrote:
> 
> * Rene Herman <rene.herman@gmail.com> wrote:
> 
> > --- a/init/main.c
> > +++ b/init/main.c
> > @@ -229,10 +229,9 @@ static int __init obsolete_checksetup(char *line)
> >  }
> >
> >  /*
> > - * This should be approx 2 Bo*oMips to start (note initial shift), and will
> > - * still work even if initially too large, it will just take slightly longer
> > + * Initial value roughly corresponds to a 1 GHz CPU
> >   */
> > -unsigned long loops_per_jiffy = (1<<12);
> > +unsigned long loops_per_jiffy = 1000000000 / HZ;
> >
> >  EXPORT_SYMBOL(loops_per_jiffy);
> 
> this is a factor of ~2400 increase - this will take an eternity to boot 
> on any older CPU.

I don't think we are using outb_p before loops_per_jiffy are
initialized -- I believe I'd see oopsen if we did. Factor 2400
increase is bad, but if it only converts 10x 1usec delay into 10x
24msec delay, it is not _that_ bad.
								Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html


\
 
 \ /
  Last update: 2007-12-16 00:01    [from the cache]
©2003-2008