AM3356: Freezing is refused

Hello Katsuyama-san,

Can you share the full log? Please include info on what commands you are using. Does the log show which tasks are not freezing?

Are you testing this on custom hardware or a TI EVM or Beagle Bone device? If you are using custom hardware, does it also occur on a TI EVM or beagle bone black?

Please be aware that tomorrow is a TI US holiday so please expect a delayed response.

Best Regards,

Anshu

Hi, Anshu-san,

I have attached the journal log (syslog_260612_not_Sleep.zip).
The refusing messages appear on lines 721, 944, and elsewhere.
The sleep command is as follows:
-----------------------------------------------------
cat /sys/power/wakeup_count > /sys/power/wakeup_count
echo suspend > /sys/power/state
-----------------------------------------------------
They are not seen in the log.

And you cannot see which tasks are not freezing in the log.
That test board is manufactured by our company.
This phenomenon does not occur on every board.
Therefore, I would like to understand the cause.

Best Regard
Katsuyama
syslog_260612_not_Sleep.zip

Hello Katsuyama-san,

Takeharu Katsuyama said:

This phenomenon does not occur on every board.

Under what conditions do you see this error?

Best Regards,

Anshu

Hi, Anshu-san,

We are currently investigating the situation.
Since the issue is occurring in the client's environment, we cannot
immediately identify the specific conditions involved.

It appears that this message is output by the `try_to_freeze_tasks()`
function in `power/process.c`, and I would like to know the conditions under
which this happens.

Best Regard
Katsuyama

Hello Katsuyama-san,

Please see the Linux SDK documentation: https://software-dl.ti.com/processor-sdk-linux/esd/AM335X/09_03_05_02/exports/docs/linux/Foundational_Components/Power_Management/pm_suspend_resume.html

For low power modes, see the commands they use.

echo suspend > /sys/power/state is not something we've tested.

Best Regards,

Anshu

Hi, Anshu-san,

echo suspend > /sys/power/state

We learned this method from your company as a way to prevent conflicts with wakeup events when transitioning to the suspend state.
So, we would like to retain this method.

Best Regard
Katsuyama

Hello Katsuyama-san,

Takeharu Katsuyama said:

We learned this method from your company as a way to prevent conflicts with wakeup events when transitioning to the suspend state.

Can you share with me where this was discussed? 

Does this error occur with echo standby > /sys/power/state ?

Does the M3 firwmare get loaded via remoteproc?

Best Regards,

Anshu

Hi, Anshu-san,

Anshu Madwesh said:

Can you share with me where this was discussed? 

We asked about measures to handle conflicts between suspend and wakeup events in the following forum.

.
e2e.ti.com/.../am3356-gpio-wakeup-from-standby-processor-sdk

And, We received the following solution via email through the agency.

Please ask the customer to use the original CM3 firmware, and
replace “systemctl suspend” with “cat /sys/power/wakeup_count >
/sys/power/wakeup_count && echo standby > /sys/power/state” in the
test to see if this solve the issue. It works for me in my test.

Similarly in the customer’s application, replace
system (“systemctl suspend”) with
system (“cat /sys/power/wakeup_count >
/sys/power/wakeup_count && echo standby > /sys/power/state”)

Anshu Madwesh said:

Does this error occur with echo standby > /sys/power/state ?

Since the issue is occurring at the customer's site, we are unable to verify it here.

Anshu Madwesh said:

Does the M3 firwmare get loaded via remoteproc?

  Yes, I believe so, because the following log can be confirmed in syslog. 

Jan 01 00:00:00 am335x-evm kernel: remoteproc remoteproc0: powering up wkup_m3
...
Jan 01 00:00:01 am335x-evm kernel: remoteproc remoteproc0: Booting fw image am335x-pm-firmware.elf, size 230332
...
Jan 01 00:00:01 am335x-evm kernel: remoteproc remoteproc0: remote processor wkup_m3 is now up

Best Regard
Katsuyama

Hello Katsuyama-san,

Was the customer always using SDK 9.3 or did they recently change to 9.3 and started seeing this error?

Best Regards,

Anshu