Jim,
I just upgraded one of my TS7200's to the ts8 kernel to get
rid of the multi-percent clock drift. My experience is
exactly as you describe. 16 seonds lost in 20 hrs.
Changing the divisor from 5085 to 5084 makes the clock
acceptably accurate. Thanks. Maybe this fix can
go into ts9 :-)
--- In Jim Jackson <> wrote:
>
> Jesse et al.
>
> I've found sometime to patch the kernel with this and try it out.
> I've found that the value "5085" caused about 8 secs to be lost in just
> over 10 hours (about 1 sec in 4500 lost) so I have used a value of 5084
> which gives a better accuracy - at least for my crystal and board.
>
> cheers
> Jim
>
> On Wed, 1 Dec 2004, Jesse Off wrote:
>
> >
> > It looks like the following patch to the kernel fixes (for the
most part)
> > the horrible time drift. Apply this patch to
> > include/asm-arm/arch-ep93xx/time.h and recompile a kernel to fix.
> >
> > //Jesse Off
> >
> > Index: time.h
> > ===================================================================
> > RCS file:
/cvsroot/ts-7200/dist/linux24/include/asm-arm/arch-ep93xx/time.h,v
> > retrieving revision 1.1
> > retrieving revision 1.2
> > diff -u -r1.1 -r1.2
> > --- time.h 22 Jul 2004 19:50:54 -0000 1.1
> > +++ time.h 1 Dec 2004 20:03:07 -0000 1.2
> > @@ -26,12 +26,6 @@
> > /* First timer channel used for timer interrupt */
> >
> > /*
> > - * We want the timer interval setup for 10,000 uSec.
> > - */
> > -#define TIMER_INTERVAL 10000 /* uSeconds */
> > -
> > -
> > -/*
> > * IRQ handler for the timer
> > */
> > static void ep93xx_timer_interrupt(int irq, void *dev_id, struct
pt_regs *regs)
> > @@ -66,8 +60,8 @@
> > * the timer load value is the timer interval
> > * divided by 2.
> > */
> > - outl( (TIMER_INTERVAL >> 1), TIMER1LOAD );
> > - outl( (TIMER_INTERVAL >> 1), TIMER1VALUE); /* countdown */
> > + outl( 5085, TIMER1LOAD );
> > + outl( 5085, TIMER1VALUE); /* countdown */
> >
> > /*
> > * Set up Timer 1 for 508 kHz clock and periodic mode.
> >
> >
> >
> >
> >
> >
> > Yahoo! Groups Links
> >
> >
> >
> >
> >
> >
> >
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