How to update initrd for root filesystem?

[Amelie]

I decompress Tegra_Linux_Sample-Root-Filesystem_R35.4.1_aarch64.tar to the rootfs directory.

Then I modified some configurations. How do I update initrd now to make the configurations take effect?

# update-initramfs -uv
Available versions:
Nothing to do, exiting.

files in /boot :

-rw-r--r--  1 root root  33M Nov 15 08:52 Image
-rw-r--r--  1 root root  33M Aug  1 19:49 Image.t19x
-rw-r--r--  1 root root 4.0K Aug  1 19:49 Image.t19x.sig
drwxr-xr-x  2 root root 4.0K Nov 15 08:52 extlinux/
-rw-r--r--  1 root root 9.4M Nov 15 08:52 initrd
-rw-r--r--  1 root root 9.4M Aug  1 19:49 initrd.t19x
-rw-r--r--  1 root root 4.0K Aug  1 19:49 initrd.t19x.sig
... etc.

[DaveYYY]

Hi,

Please check the developer guide:
https://docs.nvidia.com/jetson/archives/r35.4.1/DeveloperGuide/text/SD/FlashingSupport.html#modifying-jetson-ram-disk