Re: Does the kernel HPET support has problems or the hwclock from util-linux?

From: rae l
Date: Thu Jul 05 2007 - 22:06:56 EST


On 7/3/07, Luca Tettamanti <kronos.it@xxxxxxxxx> wrote:
rae l <crquan@xxxxxxxxx> ha scritto:
> from this address, I know util-linux-2.12r is the latest:
> http://www.kernel.org/pub/linux/utils/util-linux/util-linux-2.12r.lsm
>
> My Dell OptiPlex 320 has 4 HPET timers and no RTC, so the execution of
> hwclock has errors:
>
> gektop@tux ~ $ /sbin/hwclock --show
> select() to /dev/rtc to wait for clock tick timed out
> gektop@tux ~ $ /sbin/hwclock --version
> hwclock from util-linux-2.12r

I think that the problem is that HPET and the CMOS RTC (list in CC)
share the same interrupt line.
I suppose that you should enable CONFIG_HPET_RTC_IRQ (my hardware has
the same "feature"); in this way /dev/rtc correcly reports that it
cannot deliver the interrupt (when HPET is enabled) and hwclock uses
direct ISA access.
I searched the CONFIG_HPET_RTC_IRQ, it's conflict with
HPET_EMULATE_RTC, that I've enabled.
so while HPET_RTC_IRQ is the good way, EMULATE_RTC is a bad way.


Luca
--
Windows NT crashed.
I'm the Blue Screen of Death.
No one hears your screams.



--
Denis Cheng
Linux Application Developer
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/