5 Jan
2005
5 Jan
'05
6:20 a.m.
Hello,
I decided to give kernel 2.6.10 a try, so I installed it in combination
with Con Kolivas system system responsiveness patch. But when I try to
run the latencytest (0.5.5), I run into the following problem:
$ modprobe latency-test
WARNING: Error inserting rtc
(/lib/modules/2.6.10-ck2-ck2-pentium4/kernel/drivers/char/rtc.ko): No such device
FATAL: Error inserting latency_test
(/lib/modules/2.6.10-ck2-ck2-pentium4/misc/latency-test.ko): Unknown symbol in module, or
unknown parameter (see dmesg)
$ dmesg
latency_test: Unknown symbol rtc_register
latency_test: Unknown symbol rtc_unregister
latency_test: Unknown symbol rtc_control
Any suggestion?
Maarten
5 Jan
5 Jan
7:33 a.m.
New subject: [linux-audio-dev] Re: problem latencytest: modprobe rtc: no such device
At Wed, 5 Jan 2005 11:20:01 +0100,
Maarten de Boer wrote:
Hello,
I decided to give kernel 2.6.10 a try, so I installed it in combination
with Con Kolivas system system responsiveness patch. But when I try to
run the latencytest (0.5.5), I run into the following problem:
$ modprobe latency-test
WARNING: Error inserting rtc
(/lib/modules/2.6.10-ck2-ck2-pentium4/kernel/drivers/char/rtc.ko): No such device
That looks problematic.
Did you enable HPET? When hpet timer is enabled, it disables RTC
interrupts. Even worse, it disables RTC irq even if HPET is not
detected from BIOS but only compiled.
(To be noted: HPET is indded on most of todays PCs, but it's never
correctly initialized via BIOS, APCI, whatever.)
Takashi
8:46 a.m.
New subject: [linux-audio-dev] Re: problem latencytest: modprobe rtc: no such device
Hi Takashi,
Thanks for your reply.
Did you enable HPET?
Hmm, it seems so... I configured my kernel using the debian .config
as oldconfig.
$ grep HPET /boot/config-2.6.10-ck2-pentium4
CONFIG_HPET_TIMER=y
CONFIG_HPET=y
# CONFIG_HPET_RTC_IRQ is not set
CONFIG_HPET_MMAP=y
When hpet timer is enabled, it disables RTC
interrupts.
Ah, even when CONFIG_HPET_RTC_IRQ is not set??
Even worse, it disables RTC irq even if HPET is not
detected from BIOS but only compiled.
I see... Ok, I will recompile my kernel with HPET disabled.
But maybe a HPET version of the latencytest would be nice,
especially since:
"The High Precision Event Timer (HPET) hardware is the future
replacement for the 8254 and Real Time Clock (RTC) periodic timer
functionality."
maarten
9:23 a.m.
New subject: [linux-audio-dev] Re: problem latencytest: modprobe rtc: no such device
At Wed, 5 Jan 2005 13:46:11 +0100,
Maarten de Boer wrote:
Yep, that wouldn't be too hard, I think.
But the problem still exists since HPET isn't enabled on many (most)
machines. Both HPET and RTC should be supported.
Takashi
Hi Takashi,
Thanks for your reply.
Perhaps that's why loading rtc module _failed_.
HPET already occupies the RTC interrupt (irq 8).
When CONFIG_HPET_RTC_IRQ is set, loading rtc.ko wouldn't fail, at
least, for other RTC functions. But latencytest wouldn't work since
RTC interrupt handling is disabled.
Did you enable HPET?
Hmm, it seems so... I configured my kernel using the debian .config
as oldconfig.
$ grep HPET /boot/config-2.6.10-ck2-pentium4
CONFIG_HPET_TIMER=y
CONFIG_HPET=y
# CONFIG_HPET_RTC_IRQ is not set
CONFIG_HPET_MMAP=y
When hpet timer is enabled, it disables RTC
interrupts.
Ah, even when CONFIG_HPET_RTC_IRQ is not set?? Even worse, it
disables RTC irq even if HPET is not
detected from BIOS but only compiled.
I see... Ok, I will recompile my kernel with HPET disabled.
But maybe a HPET version of the latencytest would be nice,
especially since: 
10:30 a.m.
New subject: [linux-audio-dev] problem latencytest: modprobe rtc: no such device
On Wed, Jan 05, 2005 at 11:20:01AM +0100, Maarten de Boer wrote:
Hello,
I decided to give kernel 2.6.10 a try, so I installed it in combination
with Con Kolivas system system responsiveness patch. But when I try to
run the latencytest (0.5.5), I run into the following problem:
$ modprobe latency-test
WARNING: Error inserting rtc
(/lib/modules/2.6.10-ck2-ck2-pentium4/kernel/drivers/char/rtc.ko): No such device
This looks familiar:
homer:/home/chrissi# modprobe rtc
FATAL: Error inserting rtc (/lib/modules/2.6.8-1-k7/kernel/drivers/char/rtc.ko): No such
device
homer:/home/chrissi# rmmod genrtc
homer:/home/chrissi# modprobe rtc
homer:/home/chrissi#
So genrtc (loaded by default on my Debian system) seems to prevents rtc from
loading correctly.
Hope this helps,
Christian
7059
days inactive
7059
days old
linux-audio-dev@lists.linuxaudio.org
4 comments
3 participants
participants (3)
-
Christian Henz -
Maarten de Boer -
Takashi Iwai