SK-AM62A-LP: Deep Sleep is not working in falcon mode

Hi Sathiya,

Can you please share what steps you followed to enable falcon mode? To my understanding, falcon mode will skip a section of the boot flow to allow for a faster boot time.

This might impact the resume path from Deep Sleep: https://software-dl.ti.com/processor-sdk-linux/esd/AM62AX/10_00_00/exports/docs/linux/Foundational_Components/Power_Management/pm_sw_arch.html

Can you share the kernel suspend logs?

Thanks,
Anshu

Hi Anshu,

Here is the thread to make in yocto.

https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1310265/sk-am62a-lp-booting-to-linux-kernel-directly-from-r5f-spl

Here is it's parent thread from SDK 8.6

https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1205638/faq-am625-how-to-boot-from-r5-u-boot-spl-directly-into-the-linux-kernel-skipping-a53-spl-and-a53-u-boot-falcon-mode

Hi Sathiya,

Did you enable low power modes while building the Arm Trusted Firmware? See here: https://software-dl.ti.com/processor-sdk-linux/esd/AM62AX/10_00_00/exports/docs/linux/Foundational_Components_ATF.html

Thanks,

Anshu

Hi Anshu,

Is there a way to do it in yocto?

Hi Sathiya,

I'm not an yocto expert but from looking through the documentation, I don't see anything that enables ATF build configurations.

Best Regards,

Anshu

Hi Sathiya,

I discussed internally about this item. If you are using the TI Yocto, it will automatically enable the LPM flag in the ATF.

Thanks,

Anshu

Hi Anshu,

It means enabling that doesn't make the wakeup sources work. Because I did falcon mode through yocto.

Hi Sathiya,

Unfortunately the yocto expert is occupied with a high priority task, so there is minimal support from the yocto side for now.

First, lets try RTC wakeup which will handle both suspend and resume sequence: https://software-dl.ti.com/processor-sdk-linux/esd/AM62AX/10_00_00/exports/docs/linux/Foundational_Components/Power_Management/pm_wakeup_sources.html#real-time-clock-rtc

If this works correctly, then there is an issue with the wakeup sources.

From the device tree, what wakeup sources are enabled? Share the output of 'cat /proc/interrupts'.

You can also use the debugging process for Deep Sleep: https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1323581/faq-processor-sdk-am62x-a-p-how-can-we-debug-deep-sleep-on-am62x-am62a-am62p-using-sysfw-trace

Best Regards,

Anshu