Linux/AM3358: Support for wakeup from DeepSleep [Suspend to RAM]

Hi,

Please post what processor you are using - OMAP, Jacinto 5, or AM335x. Also post the Linux version you use.

Hi Biser,

Thank you for your reply.
Using AM3358 sitara processor & the kernel version is 4.14.40.
Sorry for the late reply


Thanks,
Viswa

Hi Pavel,

Thank you for your reply

Currently we are using the kernel 4.14.40 that comes with AM335x TI PSDK Linux v5.00.

but still we are seeing the issue ...resume is not happening from deepsleep0

Thanks,

Viswa

Hi Pavel,

Thank you for reply

Currently using the kernel 4.14.40 that comes with AM335x TI PSDK Linux v5.00.

still we are seeing the issue ...resume is not happening from deepsleep0

Note:- RTC has been disabled in our board. is it required for deepsleep support on AM3358

Thanks,

Viswa

Viswa,

For wake up source from AM335x DeepSleep0 state, you should use:

- UART
- GPIO0
- Touchscreen

You can also use RTC alarm event, but RTC is optional and you can disable it for DeepSleep0 mode.

Check below pointers for debug hints:

processors.wiki.ti.com/.../Debugging_AM335x_Suspend-Resume_Issues
www.ti.com/.../sprac74a.pdf
processors.wiki.ti.com/.../AM335x_Schematic_Checklist

Regards,
Pavel

Hi Pavel,

Resume is working in standby mode, system is able to resume from suspend through UART & USB wake sources.
When we write "mem" to "/sys/power/state" CPU is being suspended which we have verified through debug logs.
However from deepsleep resume is not happening through UART or USB. We think this is because of peripheral power domain(PD_PER) shut down as per deepsleep power mode specified in the TRM.
We have loaded am335x-pm-firmware.elf 0x192 version & am335x-bone-scale-data.bin firmware and made sure that CM3 is up and running.
In the deepsleep state any interrupt from external wake up sources should wake the CPU with the help of CM3 , which is not happening.
Ours is automotive SoC DRA604 which is used on a CSB(Daughter board). So, we don't have touch screen.

Could you suggest any debug options for CM3.
Meanwhile will check with our hardware team regarding the constraints as mentioned in the link shared by you.


Thanks,
Viswa

Viswa,

Which UART module you are using? DeepSleep0 can resume only by UART0. UART0 belongs to PD_WKUP. Check below AM335x TRM section:

8.1.4.5 Wakeup Sources/Events

Regards,
Pavel

Hi Pavel,

we are using UART0 as a wake up resource in both standby & deepsleep0
It worked in standby mode but not from deepsleep0

Thanks,
Viswa

Viswa,

I tested deepsleep0/mem mode on AM335x TI EVM TMDXEVM3358 with PSDK 5.02 (kernel 4.14.79, pre-built binaries) and UARt wakeup from deepsleep0 is working fine:

root@am335x-evm:~# echo mem > /sys/power/state
[  125.447670] PM: suspend entry (deep)
[  125.451321] PM: Syncing filesystems ... done.
[  126.154674] Freezing user space processes ... (elapsed 0.004 seconds) done.
[  126.165762] OOM killer disabled.
[  126.169232] Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done.
[  126.178417] Suspending console(s) (use no_console_suspend to debug)
[  126.344738] pm33xx pm33xx: PM: Successfully put all powerdomains to target state
[  126.344738] PM: Wakeup source UART
[  126.369528] net eth0: initializing cpsw version 1.12 (0)
[  126.467935] Atheros 8031 ethernet 4a101000.mdio:00: attached PHY driver [Atheros 8031 ethernet] (mii_bus:phy_addr=4a101000.mdio:00, irq=POLL)
[  126.649385] OOM killer enabled.
[  126.652553] Restarting tasks ... done.
[  126.696856] PM: suspend exit
root@am335x-evm:~#

I am attaching the full boot up log:

am335x_pm_log

Check the boot up log and compare with yours, check for differences related to power management and CM3 firmware.

You can check what HW/SW differences you have between AM335x EVM and your custom board and check how these differences impact the wake-up procedure.

Check also if below wiki pages will be in help:

Check also the pdf file attached in below e2e post, it has some good debug hints:

You can also put no_console_suspend in your boot args, thus you might have more debug messages that can point you to the root cause.

Regards,
Pavel

If you have no more questions related to the subject of this e2e thread, please close/verify/resolve this thread.

Regards,
Pavel