lkml.org 
[lkml]   [2007]   [Jun]   [22]   [last100]   RSS Feed
Views: [more markup]   [less markup]   [headers]   [forward]  
 
Messages in this thread
/
DateFri, 22 Jun 2007 16:10:47 +1000
SubjectRe: [RFC] clocksouce implementation for powerpc
From(Tony Breeds)
On Wed, Jun 20, 2007 at 08:53:47PM +0400, Sergei Shtylyov wrote:

Hi Sergei,
	Thanks for taking the time to look over my patch.

>    I guess it's been based on the prior work by John Stultz (and me too :-)?

At some level I guess so.  John did send me a patch a while ago.

>    If you mean the init. part, this has been already done by me -- I've 
> implemented read_persistent_clock() and got rid of xtime setting. What's 
> left is to implemet update_persistent_clock() and get rid of 
> timer_check_rtc()...

Actually I think that comment is redundant.  and should be removed
sorry.

>    Perhaps we even need to raise the rating to 300 or 400 -- according to 
> what <linux/clocksource.h> says?

Sure.

> >+	.flags        = CLOCK_SOURCE_IS_CONTINUOUS,
> >+	.mask         = CLOCKSOURCE_MASK(64),
> >+	.shift        = 22,
> 
>    PPC64 has issues with the fixed shift value, see:
> 
> http://patchwork.ozlabs.org/linuxppc/patch?id=11125

Thanks!

> >+	.mult         = 0,	/* To be filled in */
> >+	.read         = NULL,   /* To be filled in */
> >+	.settimeofday = NULL,   /* To be filled in */
> 
>    I don't quite understand why not just init them right away?  The values 
> are fixed anyways.

Well at least mult needs to be calculated at runtime, and I prefer to
have the structure near the top of the file at which stage the
read/settimeofday functions aren't defined.

Yours Tony

  linux.conf.au        http://linux.conf.au/ || http://lca2008.linux.org.au/
  Jan 28 - Feb 02 2008 The Australian Linux Technical Conference!
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2007-06-22 06:13    [W:0.459 / U:0.890 seconds]
©2003-2008 Jasper Spaans