AM623: What is the time accuracy that AM623 can achieve through TSN synchronization?

Using linuxptp/ptp4l/gPTP, 802.1AS-2011 compliant we observe +- 10ns error to the leader (master) port in p2p mode at 1Gbps. In theoretical terms just the RGMII interface at 1G will cause +-8ns. In a more complex network with multiple bridges the error compared to grandleader (gransmaster) can compound to a larger number. phc2sys is used to calibrate Linux system clock to the clock from gPTP. This disciplining is a continuous process.

RTC management is a separate topic, you can use standard Linux commands to adjust hwclock (RTC) based on system clock. Accuracy is much more coarse when the device is in sleep mode and gPTP is not running. Once the AM623 wakes up and gPTP starts running again the system time will converge to the same level in a few seconds.

See https://software-dl.ti.com/processor-sdk-linux-rt/esd/AM62X/latest/exports/docs/linux/How_to_Guides/Target/How_to_suspend_to_ram_on_AM62x.html for an RTC example.

  Pekka