RE: How to get /proc/acpi/alarm to work?

RE: How to get /proc/acpi/alarm to work?

[Li, Shaohua]

Hi,
>
>Li, Shaohua schrieb:
>> Is it possible you could try the patch at
>> http://bugzilla.kernel.org/show_bug.cgi?id=5833?
>> Christian Lupien's patch made a lot of improvements on alarm.
>
>Thanks, but no, that didn't solve the problem.
>
>Let me rephrase the description. My BIOS has a different ACPI alarm
>value than the value stored in /proc/acpi/alarm.
>
>
>
>I can set the RTC alarm wakeup in the BIOS's ACPI settings to:
>
>  enabled: yes
>  day:     18
>  hour:    15
>  minute:  10
>  second:  30
>
>If I look at /proc/acpi/alarm, it doesn't show me "****-**-18 15:10:30"
>as one would expect, but a different value.
>
>When doing
>
>  echo "2006-01-18 15:20:45" > /proc/acpi/alarm
>
>I get (with Christian's patch):
>
>  cat /proc/acpi/alarm
>  "****-**-** 15:20:45 +int (2006-01-18 10:50:12)"
>
>Now, after rebooting, the BIOS _still_ shows 15:10:30 on day 18 in its
>ACPI settings.
>
>
>So on my system, the BIOS's RTC alarm wakeup ACPI setting appears to be
>something different than what /proc/acpi/alarm has access to.
>
>Also, the /proc/acpi/alarm setting does not wake the system from S5,
>while the BIOS setting can. And the BIOS can handle the day's number as
>a wakeup setting, while /proc/acpi/alarm cannot.
>
>Any idea how to read and change the BIOS's RTC alarm wakeup from Linux?
>I have read from users of other mainboards that it works for them
>(including the day's number).
>
>As I wrote before, the nvram-wakeup method does not work on this
>mainboard, either.
Can you enable the RTC driver? IIRC, without it, the date you see is
wrong, which might make you set wrong alarm.

Thanks,
Shaohua

Re: How to get /proc/acpi/alarm to work?

[Hanno Mueller]

Hi,

thanks.

Li, Shaohua schrieb:
> Can you enable the RTC driver? IIRC, without it, the date you see is
> wrong, which might make you set wrong alarm.

Yes, it is enabled (now). But no, it didn't help.



I still have two different alarm settings.

1) The setting stored in the BIOS's ACPI section as "RTC alarm". I can
choose a time and a specific day of the month.

2) The setting stored in /proc/acpi/alarm - there I can only choose the
time, not the day.

These two settings appear to be completely independent from each other.

Also, the 2nd setting does not work. I can change it and the computer
remembers it between reboots, but the BIOS does not wake up the system
from S5. The 1st setting is able to wake up the system.

Two questions: Why are there two different settings? I thought there was
just one?

And more important to me: How can I access the 1st alarm time from
Linux? Since the BIOS lists it in its ACPI settings section, I guess
there is some way to access it through ACPI.

Regards,

Hanno

RE: How to get /proc/acpi/alarm to work?

[Li, Shaohua]

Hi,
>
>thanks.
>
>Li, Shaohua schrieb:
>> Can you enable the RTC driver? IIRC, without it, the date you see is
>> wrong, which might make you set wrong alarm.
>
>Yes, it is enabled (now). But no, it didn't help.
>
>
>
>I still have two different alarm settings.
>
>1) The setting stored in the BIOS's ACPI section as "RTC alarm". I can
>choose a time and a specific day of the month.
>
>2) The setting stored in /proc/acpi/alarm - there I can only choose the
>time, not the day.
>
>These two settings appear to be completely independent from each other.
>
>Also, the 2nd setting does not work. I can change it and the computer
>remembers it between reboots, but the BIOS does not wake up the system
>from S5. The 1st setting is able to wake up the system.
>
ACPI alarm can only wakeup system from S3 and wakeup from S4 is
optional. IIRC, it can't wakeup system from S5.

Thanks,
Shaohua

RE: How to get /proc/acpi/alarm to work

[Li, Shaohua]

Hi,
>Linux: 2.6.15.1 vanilla
>Mainboard: ASRock P4V88+, revision 1.00
>BIOS: Updated to 1.6 (latest release from manufacturer's site)
>
>
>My mainboard's BIOS allows to set an RTC wakeup time and day (not month
>or year) in its ACPI settings.
>
>This will wakeup the system from the S5 state.
>
>
>Problem: It is not possible to set this value through /proc/acpi/alarm.
>
>
>It's possible to write valid value to /proc/acpi/alarm and to retrieve
>it [1]:
>
># echo "2006-01-18 03:00:00" > /proc/acpi/alarm
># cat /proc/acpi/alarm
>2006-01-18 03:00:00
>
>After a reboot the stored value is broken [2]:
>
># cat /proc/acpi/alarm
>2006-00-00 03:00:00
>
>The alarm time does not wake up the system. It doesn't wake up at
>03:00:00 BIOS time, not today, not tomorrow, not on 2006-01-18.
>
>Also, the alarm time does not show up in the BIOS's ACPI settings.
>There, one can still find the old values that where entered several
>boots ago.
>
>
>Since the mainboard explicitely lists this function in its ACPI
>settings, I guess that the Linux kernel somehow doesn't handle my
>mainboard right.
>
>I'm aware that there are many broken ACPI implementations on mainboards
>out there. Is there any way I can find out how to fix this issue? Is
>there a debugging guide for this? [3]
Is it possible you could try the patch at 
http://bugzilla.kernel.org/show_bug.cgi?id=5833?
Christian Lupien's patch made a lot of improvements on alarm.

Thanks,
Shaohua

Re: How to get /proc/acpi/alarm to work?

[Hanno Mueller]

Li, Shaohua schrieb:
> Is it possible you could try the patch at 
> http://bugzilla.kernel.org/show_bug.cgi?id=5833?
> Christian Lupien's patch made a lot of improvements on alarm.

Thanks, but no, that didn't solve the problem.

Let me rephrase the description. My BIOS has a different ACPI alarm
value than the value stored in /proc/acpi/alarm.



I can set the RTC alarm wakeup in the BIOS's ACPI settings to:

  enabled: yes
  day:     18
  hour:    15
  minute:  10
  second:  30

If I look at /proc/acpi/alarm, it doesn't show me "****-**-18 15:10:30"
as one would expect, but a different value.

When doing

  echo "2006-01-18 15:20:45" > /proc/acpi/alarm

I get (with Christian's patch):

  cat /proc/acpi/alarm
  "****-**-** 15:20:45 +int (2006-01-18 10:50:12)"

Now, after rebooting, the BIOS _still_ shows 15:10:30 on day 18 in its
ACPI settings.


So on my system, the BIOS's RTC alarm wakeup ACPI setting appears to be
something different than what /proc/acpi/alarm has access to.

Also, the /proc/acpi/alarm setting does not wake the system from S5,
while the BIOS setting can. And the BIOS can handle the day's number as
a wakeup setting, while /proc/acpi/alarm cannot.

Any idea how to read and change the BIOS's RTC alarm wakeup from Linux?
I have read from users of other mainboards that it works for them
(including the day's number).

As I wrote before, the nvram-wakeup method does not work on this
mainboard, either.

Regards,

Hanno


-- 
epublica GmbH
http://www.epublica.de

Open Business Club - join: http://www.openbc.com/go/invanon/2

How to get /proc/acpi/alarm to work

[Hanno Mueller]

Hello,


Linux: 2.6.15.1 vanilla
Mainboard: ASRock P4V88+, revision 1.00
BIOS: Updated to 1.6 (latest release from manufacturer's site)


My mainboard's BIOS allows to set an RTC wakeup time and day (not month
or year) in its ACPI settings.

This will wakeup the system from the S5 state.


Problem: It is not possible to set this value through /proc/acpi/alarm.


It's possible to write valid value to /proc/acpi/alarm and to retrieve
it [1]:

# echo "2006-01-18 03:00:00" > /proc/acpi/alarm
# cat /proc/acpi/alarm
2006-01-18 03:00:00

After a reboot the stored value is broken [2]:

# cat /proc/acpi/alarm
2006-00-00 03:00:00

The alarm time does not wake up the system. It doesn't wake up at
03:00:00 BIOS time, not today, not tomorrow, not on 2006-01-18.

Also, the alarm time does not show up in the BIOS's ACPI settings.
There, one can still find the old values that where entered several
boots ago.


Since the mainboard explicitely lists this function in its ACPI
settings, I guess that the Linux kernel somehow doesn't handle my
mainboard right.

I'm aware that there are many broken ACPI implementations on mainboards
out there. Is there any way I can find out how to fix this issue? Is
there a debugging guide for this? [3]


Thanks,

Hanno



[1] Yes, when I tried this, it was a date and time in the future. I read
somewhere that a past or invalid date will turn off the alarm time setting.

[2] I read in a forum that calling /sbin/hwclock can mess with the alarm
value. When I tried the things above, I removed the /sbin/hwclock calls
from my system's init.d-scripts, but that didn't help.

[3] The same mainboard does not work with nvram-wakeup, which is a
popular older program used by many Linux vdr/pvr setups. nvram-wakeup
uses /dev/nvram to store the wakeup time directly in the NVRAM section.
Ugly, but it works with two other (older) mainboards I tried. On my
current mainboard, however, the alarm timer bytes do not appear to be
accessible through NVRAM.

Re: How to get /proc/acpi/alarm to work *?*

[Hanno Mueller]

Hello,

> Problem: It is not possible to set this value through /proc/acpi/alarm.

Darn. The subject should have contained a question mark.

Regards,

Hanno