Re: Debian parisc config for 2.6.26 broke the real time clock

[James Bottomley <James.Bottomley@HansenPartnership.com>]

On Tue, 2008-09-09 at 10:58 -0600, dann frazier wrote:
> On Mon, Sep 08, 2008 at 11:58:22AM -0500, James Bottomley wrote:
> > On Mon, 2008-09-08 at 18:37 +0200, Bastian Blank wrote:
> > > On Sat, Sep 06, 2008 at 10:06:26AM -0500, James Bottomley wrote:
> > > > Parisc is a CONFIG_GEN_RTC architecture (we use the generic real time
> > > > clock driver).
> > > 
> > > Well.
> > > 
> > > >                 Starting with 2.6.26, debian is now enabling
> > > > CONFIG_RTC_CLASS (for platforms with specific RTC drivers) which
> > > > disables CONFIG_GEN_RTC and means that hwclock (and ntp tracking) are
> > > > broken on parisc with debian kernels 2.6.26 and above.
> > > 
> > > Yes. Most arches already needs it anyway.
> > > 
> > > > All of the arch/parisc/config files get this right, so someone at debian
> > > > must have screwed up somehow.  The config option CONFIG_RTC_CLASS must
> > > > be set to 'N' for all parisc systems.
> > > 
> > > Apparently hppa uses its special rtc type.  I propose that you take a
> > > look at drivers/rtc/rtc-ppc.c and write a wrapper rtc module.
> > 
> > That may be the way forwards depending on what the RTC developers say,
> > but it certainly won't fix the 2.6.26 regression.
> > 
> > > >                                        I'd suggest checking the debian
> > > > kernel configs against the in-tree default files to see if there are any
> > > > other cockups like this.
> > > 
> > > If there are, this are bugs in the kernel themself. I'm no hppa
> > > developer so I won't waste my time with such.
> > 
> > Hardly, the bug is actually in the debian configs.  You have
> > CONFIG_RTC_CLASS as a generic override.  This is wrong, it needs to be
> > subordinate to CONIFG_GEN_RTC.  The quick fix would be to move the
> > CONFIG_RTC_CLASS sequence down from generic to the architectures ... if
> > you're incapable of doing that, I might be able to find time to look at
> > doing it for you.
> > 
> > The real bug looks to be the debian config system which relies on
> > concatenation ... what's really needed is a way of turning
> > CONFIG_RTC_CLASS off on parisc while keeping RTC_CLASS generic for those
> > architectures that need it.
> 
> fyi, I've got an hppa build in progress - disabling RTC_CLASS causes
> the symbols below to be removed (essentially, ^rtc_*)

Thanks Dann ... are you the person in charge of the builds then?

> I'm not sure what's behind the hppa/ABI removal commits - I didn't see
> this discussed on the list - but I think it should be safe to remove
> these symbols from the ABI files if we can demonstrate that none of
> the conglomerate packages use them.
> 
> rtc_class_close
> rtc_class_open
> rtc_device_register
> rtc_device_unregister
> rtc_irq_register
> rtc_irq_set_freq
> rtc_irq_set_state
> rtc_irq_unregister
> rtc_month_days
> rtc_read_alarm
> rtc_read_time
> rtc_set_alarm
> rtc_set_mmss
> rtc_set_time
> rtc_time_to_tm
> rtc_tm_to_time
> rtc_update_irq
> rtc_valid_tm
> rtc_year_days

They certainly have to be inessential to the parisc ABI ... they don't
work if anything's actually trying to use them.

James