Making it work with L4T v32.4.4

[Xavier0301]

I have to report my fix for making it work for L4T v32.4.4, on a Jetson AGX Xavier.

First, as a prerequisite to what follows, in buildPatchedKernel.sh, replace every occurence of 32.1.0 with 32.4.4 (or for people in the future: whatever the newest version is). This allows the script to run freely, even if correctness has not been proven by the author.

Now, the real fun begin. When doing ./buildPatchedKernel.sh you might get an error in the script makeKernel.sh. In particular, make Image does not work.

The /kernel/nvidia/... stuff we download in the "Getting Kernel sources" part of ./buildPatchedKernel.sh has been modified since jetsonhacks wrote this script.

The problem happens because make is configured to stop when an warning is caught at a certain point in the compilation.
In particular when compiling the file /usr/src/kernel/nvidia/drivers/video/tegra/dc/hdcp/hdmihdcp.c, a unused variable warning is thrown and is interpreted as an error by make, which fails the compilation.

I can get into the details here, but what is interesting is the fix:

1. Open a terminal and cd /usr/src/kernel/nvidia/drivers/video/tegra/dc/hdcp/. If it does not exist yet, run ./buildPatchedKernel.sh and wait for it to fail in the same way I described above before going pack to these instructions.
2. Without quitting the terminal, open Files and go to /usr/src/kernel/nvidia/drivers/video/tegra/dc/hdcp/ (you are going to understand why)
3. Open a new terminal and run ./buildPatchedKernel.sh
4. When you see that ./buildPatchedKernel.sh is starting to "Patching and configuring kernel", then it is done "Getting Kernel sources" and now you have to do two things quickly:
5. In the first terminal window, run chmod a+x hdmihdcp.c. This grants you access to write the file.
6. In the Files window, open hdmihdcp.c and go to line 1940 and delete: unsigned char nonce[HDCP_NONE_SIZE]. This is the line which caused the compilation to fail: nonce is unused (warning) and every warning counts as an error because of the -Werror flag in the makefile of a parent directory.
7. Save the change.
8. If you did it fast enough, compilation will complete smoothly (at least for L4T v32.4.4) .

This sure was not a very eloquent post, nor does it really qualify as an issue, but I hope it helps someone running into the same troubles as I did.

Buying a RealSense camera sure was a great match for the Jetson!