L4T Jetson/OTA

What is the for?

This page is a developer wiki for customizing deb package from official Jetpack 4.3 release. Please be careful this is not a official document.

Get prepared

Please make sure you already have a ubuntu host installed with Jetpack4.3. All the steps below are on this host but not DUT.

Example

In this page, we will use nvidia-l4t-kernel as a sample to demo how to rebuild it.

1. Extract the official deb package

dpkg -x nvidia-l4t-kernel*.deb origin
dpkg -e nvidia-l4t-kernel*.deb origin/debian

After the extraction, you shall see some files under origin/debian/:

 control
 md5sum
 postinst/postrm/triggers

2. Prepare the metadata under <OUT>/debian/
To generate the deb file, it is not enough to use only above files. You need to have below files in your debian folder.
Please refer to debian manuals [1] for more detail.

.
└── debian
   ├── changelog
   ├── compat
   ├── control
   ├── copyright
   ├── install
   ├── postinst
   ├── rules
   ├── source
   │   └── format
   └── triggers

3. Some simple examples if you don't know how to write these metadata

• rules

#!/usr/bin/make -f
.PHONY: binary
clean:
       dh clean
binary:
       dh binary
build:
override_dh_strip:
override_dh_shlibdeps:

• copyright and changelog

cp origin/usr/share/doc/nvidia-l4t-kernel/copyright <OUT>/debian/
gunzip -c origin/usr/share/doc/nvidia-l4t-kernel/changelog.Debian.gz > <OUT>/debian/changelog

• install

This file indicates the path where your necessary files are located.

debian/out/* /

Then under <OUT>/debian/out/, you need to put below files

boot/Image
lib/modules/<KERNELVER>/kernel/
lib/modules/<KERNELVER>/modules.*

4. Build Use below command to build the deb file.

cd <OUT>
CC=aarch64-linux-gnu-gcc dpkg-buildpackage -uc -b -d -a arm64