SK-AM64: Time synchronization between A53 and R core.

Hello Macieji,

The time can be synchronized, but I do not believe we have an example of it at this point. Give me a day or so to check with my team members.

Regards,

Nick

Hello Macieji,

Are you on the same team as Jakub? https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1133559/am6442-time-sharing-between-am53-and-core-r5

There are two options that come to mind as easier to implement:
1) synchronize a CPTS, then use CPTS to send a periodic pulse to the remote cores through the time sync router
2) synchronize a counter / timer, and then read the counter / timer from R5

If you are directly adjusting the Linux system clock, I would expect those changes to be observable on the GTC as discussed here: https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1133559/am6442-time-sharing-between-am53-and-core-r5/4207333#4207333

There is an example of using the CPTS to send a 1pps signal to an external signal through the time sync router in the CPSW driver chapter, CPTS subsection, Pulse Per Second (PPS) sub-sub section: https://software-dl.ti.com/processor-sdk-linux/esd/AM64X/08_04_01_04/exports/docs/linux/Foundational_Components/Kernel/Kernel_Drivers/Network/CPSW3g.html#common-platform-time-sync-cpts-module We should be able to route the signal in the time sync router to the R5 instead, but it would require additional interrupt configuration of the Data Movement Subsystem (DMSS) Interrupt Aggreggator (I believe defined in the AM64x Linux devicetree in node inta_main_dmss). At this point I have not looked into setting up the interrupt aggregator.

Regards,

Nick