please remember to run apply_binaries.sh before flash…
$ tar xf ${L4T_RELEASE_PACKAGE}
$ cd Linux_for_Tegra/rootfs/
$ sudo tar xpf …/…/${SAMPLE_FS_PACKAGE}
$ cd …
$ sudo ./apply_binaries.sh
Read the document first.
https://docs.nvidia.com/jetson/archives/r35.1/DeveloperGuide/text/IN/QuickStart.html