AM3352: resume from standby problem with kernel 6.1.46

Angel Falcon

Part Number: AM3352

Hello,

We are moving our own am3352 design FW from SDK 05.03.00.07 to SDK 09.01.00.00, so we are now running kernel 6.1.46.

System seems to be working fine, but we are having problems trying to get uart to wake the system from standby. The system is able to enter standby mode, but then never wakes up.

This works with kernel 4.19.94, and now I have followed the instructions from

https://software-dl.ti.com/processor-sdk-linux/esd/AM335X/09_01_00_001/exports/docs/linux/Foundational_Components/Kernel/Kernel_Drivers/Power_Management/pm_suspend_resume.html

I also checked with BBB and it did not work:

root@BeagleBone:/home# uname -a
Linux BeagleBone 6.1.80-ti-r34 #1bullseye SMP PREEMPT Fri Mar 22 11:06:21 UTC 2024 armv7l GNU/Linux

root@BeagleBone:/home# echo enabled > /sys/devices/platform/ocp/44c00000.interconnect/44c00000.interconnect:segment@200000/44e09050.target-module/44e09000.serial/power/wakeup
root@BeagleBone:/home# echo enabled > /sys/devices/platform/ocp/44c00000.interconnect/44c00000.interconnect:segment@200000/44e09050.target-module/44e09000.serial/tty/ttyS0/power/wakeup
root@BeagleBone:/home# cat /sys/devices/platform/ocp/44c00000.interconnect/44c00000.interconnect:segment@200000/44e09050.target-module/44e09000.serial/power/wakeup
enabled
root@BeagleBone:/home# cat /sys/devices/platform/ocp/44c00000.interconnect/44c00000.interconnect:segment@200000/44e09050.target-module/44e09000.serial/tty/ttyS0/power/wakeup
enabled

root@BeagleBone:/home# echo standby > /sys/power/state

Then I press keys on my console but it never wakes up.

Could you please help us with this issue?

Best regards and thank you

Angel

5 months ago

0 Anshu Madwesh 5 months ago

TI__Genius 10660 points

Hi Angel,

Can you review these two threads? There was a similar issue where the config file needs to be updated.

https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1333959/beagl-bone-black-sdk-9-1-suspend-not-working

https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1354190/re-beagl-bone-black-sdk-9-1-suspend-not-working

Best Regards,

Anshu

0 Angel Falcon 5 months ago in reply to Anshu Madwesh

Expert 1160 points

Hi Anshu,

I have double checked instructions from TI documentation and config file seems to be fine:

CONFIG_FW_LOADER_USER_HELPER=y
CONFIG_FW_LOADER_USER_HELPER_FALLBACK=y
CONFIG_MAILBOX=y
CONFIG_OMAP2PLUS_MBOX=y
CONFIG_WKUP_M3_RPROC=y
CONFIG_SOC_TI=y
CONFIG_WKUP_M3_IPC=y
CONFIG_TI_EMIF_SRAM=y
CONFIG_AMX3_PM=y
CONFIG_RTC_DRV_OMAP=y
CONFIG_SUSPEND=y
CONFIG_SUSPEND_FREEZER=y

also elf FW is loaded:

dmesg | grep pm
root@A137K3:~# dmesg | grep pm
[ 3.102358] remoteproc remoteproc0: Booting fw image am335x-pm-firmware.elf, size 230332

dmesg | grep CM3
[ 3.125411] wkup_m3_ipc 44e11324.wkup_m3_ipc: CM3 Firmware Version = 0x192

Last reply from Bin Liu in the second thread says that he found the same problem, is there any solution now?

We also need to resume from gpio0_3. We defined this input in our .dts file and it is available in the FS:

root@A137K3:/home# cat /sys/devices/platform/gpio_buttons\@0/power/wakeup
enabled

But again it is not possible to resume. I think it could be the same problem.

Best regards and than you

Angel

0 Anshu Madwesh 5 months ago in reply to Angel Falcon

TI__Genius 10660 points

Hi Angel,

Thanks for the update. Looks like there is a bug for UART wakeup source. I'll file this bug to the SW development team.

Best Regards,

Anshu

0 Angel Falcon 5 months ago in reply to Anshu Madwesh

Expert 1160 points

Hi Anshu,

Thank you for your answer.

I have also checked BBB to wake up with gpio0_26. It works fine with kernel version 4.19.94, but not with kernel 6.1.80.

It is a key feature for our product to wake from UART and from gpio0_x, so could you please also inform your SW development team about the gpio0_x wakeup bug?

It appears that SDK 09.01.00.001 is the latest official release from TI, and it contains kernel 6.1.46. Is it possible to use a more recent kernel version from TI that fixes these bugs?

Best regards and thank you

Angel

0 Anshu Madwesh 5 months ago in reply to Angel Falcon

TI__Genius 10660 points

Hi Angel,

Thanks for letting me know. I'll update the bug report about the GPIO issue as well.

TI will only provide support for the kernel version used in the SDK. You're welcome to review kernel changes to see if it helps fix the bugs, but it would be outside our support scope.

Best Regards,

Anshu

0 Angel Falcon 5 months ago in reply to Anshu Madwesh

Expert 1160 points

Hi Anshu,

I understand that you only support official releases. I was thinking of the versions you release on the official TI github
git.ti.com/.../

I did a quick search here and found no fix for this bug up to version 6.1.91.
If you do make a fix, how can I know about that and where can I find the new version fixing the bug?

Best regards and thank you

Angel

0 Anshu Madwesh 5 months ago in reply to Angel Falcon

TI__Genius 10660 points

Hi Angel,

I'm not aware of any way to track the bug. You can check on the issues tracker, but I'm not sure how often its updated: https://software-dl.ti.com/processor-sdk-linux/esd/AM335X/09_01_00_001/exports/docs/devices/AM335X/linux/Release_Specific_Release_Notes.html#issues-tracker

I've made a note to update this thread if a solution is found.

Thanks,

Anshu

0 Angel Falcon 4 months ago in reply to Anshu Madwesh

Expert 1160 points

Hi Anshu,

Is it possible to know when you are planning to find a solution for this suspend/resume bug in your roadmap?

It is an important feature and none of the 6.x.x kernel versions seem to work.

As we said before, for our product power management is a key feature.

Best regards and thank you

Angel

0 Anshu Madwesh 4 months ago in reply to Angel Falcon

TI__Genius 10660 points

Hi Angel,

There's no update as of now. I'll message the software development team if they have a plan

Best Regards,

Anshu

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AM3352: resume from standby problem with kernel 6.1.46