Dear NXP team,
I'm looking at the i.MX 8M Plus processor and its ENET_QOS ethernet controller for use in real-time ethernet networks.
In some use cases we require precise time synchronization between the network (i.e. RX/TX timestamps, EST transmit schedule) and software timers (e.g. CLOCK_MONOTONIC, CLOCK_REALTIME on Linux).
For proper cross-timestamping we would need a way to get synchronized timestamps from the ENET_QOS timers (that is the base for network timestamps) and the ARM generic timer (which is the base for Linux CLOCK_*).
The TRM seems a bit sparse on details, or at least I couldn't find the necessary information:
Regards,
Dominic
Hello,
.The System Counter (SYS_CTR) is a programmable system counter, which provides a
shared time base to multiple processors. System Counter Timer is configured to generate a periodic interrupt at a certain interval.
2.As far as I know the ENET_QOS external system time source is unusable for your purpose.
3.For the question 3, do you mean you want to use the SYS_CTR / A53 generic counter value to write to some register to sync with ENET_QOS_1588 ? I think this can't work.
For the different devices sync time with each other, you can reference the following doc:
Cognex-i-MX-8M-Plus-Synchronize-devices-outside-of-the-8M-Plus
Regards