Is there any a counter used to realize the timekeeping?

[sunjiandong]

Hi sir
we want use a counter to do timekeeping. The requirement is as below:
1.The accuracy is ns.
2.It can be set to 0 and then count from 0 auto.
3.I can read and reset it from the userspace
Thanks!

[ShaneCCC]

Maybe googling would get helpful information.

[sunjiandong]

Hi sir
Can the TSC be used for ?
Thanks!

[sunjiandong]

Hi sir
We don’t want to sync the system time during the time-sync. So we want a hardware counter to save the UTC time which read from the GPRMC and count the ns from 0 when PPS is received.
Can you give me any suggestions about hardware count?
Thanks!

[ShaneCCC]

Maybe reference to below topic.

PTP synchronization and PPS output from Nvidia NX

Hi, We have two devices with NX. Each NX device controls its own camera via GPIO. We would like to synchronize NX devices via PTP. After synchronization, we would like each NX device to send a pulse per second to its own camera. Currently, we could synchronize two NX devices via PTP. Both system clocks are synced. But we are trying to find a way to send a pulse per second to the camera via GPIO. We tried a user-space program that will toggle a GPIO every second, but we see the pulses drift …

[sunjiandong]

Hi sir
It have no relations with my problem.
I want a hardware count for the UTC time, and it doesn’t modify the linux system time during the time-sync.
From the Orin-TRM_DP10508002v1.1p.pdf, I can see the TSC and second TSC. So whether these counts can be used? If yes, how to enable and use them?
Thanks!

[ShaneCCC]

OK, I don’t have much idea for it.
Maybe check the TRM if any function match your request.

Thanks