cvs commit: src/sys/dev/mk48txx mk48txx.c mk48txxreg.h

[John Baldwin]

On Sunday 26 September 2004 02:19 pm, Marius Strobl wrote:
> On Mon, Sep 20, 2004 at 01:46:13PM -0400, John Baldwin wrote:
> > On Sunday 19 September 2004 05:38 pm, Marius Strobl wrote:
> > > marius      2004-09-19 21:38:11 UTC
> > >
> > >   - Fix two off-by-one errors in the handling of the day of week. The
> > >     genclock code represents the dow as 0 - 6 with 0 being Sunday but
> > > the mk48txx use 1 - 7 with 1 being Sunday. In the settime function when
> > > writing the dow to the clock the range wasn't adjusted accordingly but
> > > the clock apparently played along nicely otherwise the second bug in
> > > the gettime function which mapped 1 - 7 to 0 - 6 but with 0 meaning
> > > Saturday would have been triggered. Fixing these makes the date being
> > > stored in the same format Sun/Solaris uses and cures the "Invalid time
> > > in real time clock. Check and reset the date immediately!" when the
> > > date was set under Solaris prior to booting FreeBSD/sparc64. [1]
> > > Looking at other clock drivers/code e.g. FreeBSD/alpha the former
> > > "bug", i.e. storing the dow as 0 - 6 even when the clock uses 1 - 7,
> > > seems to be common but might be on purpose for compatibility when
> > > multi-booting with other OS which do the same. So it might make sense
> > > to add a flag to handle the dow off-by-one for use of this driver on
> > > platforms other than sparc64.
> >
> > Hmm, I get them occasionally on my Alphas which only run FreeBSD, so I
> > think it's probably a bug that needs to be fixed in FreeBSD/alpha.
>
> Bruce Evans pointed me at src/sys/i386/isa/clock.c revision 1.191 which
> fixed the same thing. According to its commit message the bug actually
> caused problems on Soekris machines.
> On my PWS which also only runs FreeBSD/alpha I ocassionally get
> "WARNING: clock gained X days -- CHECK AND RESET THE DATE!". This could
> be a problem similar to the one on Soekris boards when using the wrong
> encoding for the weekday but I haven't looked into it, yet.
> Do you also get "clock gained X days" warnings or something different?
> Do you have an idea when this happens?

Yes I get those exact messages.  It seems to happen if the machine is off for 
more than a couple of days.  Probably if it is off over the weekend. ;)  I've 
seen it on both Alpha machines I have (PWS and DS20).

-- 
John Baldwin <jhb at FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve"  =  http://www.FreeBSD.org