I am working with several Tegra Jetson, some are TX1, a few TX2. I am facing the same issue in all of them.
I can set the clock fine with “date” command. The time is good some minutes after, even if I reboot the tegras. But if I leave them unplugged one day and turn them on the following day, I see all strange behaviors. For example they could stay “frozen” at the time they were turned off, or change randomly even to 2016, etc.
1 # R24 (release), REVISION: 2.1, GCID: 7791156, BOARD: t210ref, EABI: aarch64, DATE: Thu Sep 29 00:59:21 UTC 2016
kernel tegra-ubuntu 3.10.96 #1 SMP PREEMPT Wed Jan 3 19:07:57 UTC 2018 aarch64 aarch64 aarch64 GNU/Linux
R28 (release), REVISION: 1.0, GCID: 9379712, BOARD: t210ref, EABI: aarch64, DATE: Thu Jul 20 07:45:59 UTC 2017
Linux tegra-ubuntu 4.4.38-tegra #1 SMP PREEMPT Thu Jan 3 19:07:16 UTC 2019 aarch64 aarch64 aarch64 GNU/Linux