CROSS_COMPILE environment variable not set when building kernel

[taylor.gardner2]

Hi, new to this arena (embedded systems, kernel builds). I’m trying to do a cross compile build for a Jetson. I’ve downloaded what I think is the source from here . . .

Jetson Linux

I then am following the instructions here . . .
https://docs.nvidia.com/jetson/archives/r34.1/DeveloperGuide/text/SD/Kernel/KernelCustomization.html
I ran the command “export CROSS_COMPILE_AARCH64_PATH=/aarch64–glibc–stable-2020.08-1”
Not sure where that path is pointing to? I don’t see an aarch64* path anywhere.
When I run “./nvbuild.sh -o $PWD/kernel_out” like it shows in step 4 I get the error that CROSS_COMPILE env variable is not set. What is this suppose to be?

Just trying to get my bearings. Any help would be appreciated. Thanks!

[enrique.ramirez]

Hi @taylor.gardner2

Looks like the the “Jetson Linux Toolchain” link mentioned in the steps, is not found.
For cross-compilation you should download the corresponding toolchain, extract it and then set your CROSS_COMPILE variable.
Please follow these steps:
https://docs.nvidia.com/jetson/archives/r34.1/DeveloperGuide/text/AT/JetsonLinuxToolchain.html#

Regards,

Enrique Ramirez
Embedded SW Engineer at RidgeRun
Contact us: support@ridgerun.com
Developers wiki: https://developer.ridgerun.com
Website: www.ridgerun.com

[taylor.gardner2]

Thanks for your reply! I wanted to make sure I’m downloading the correct package. Which one? . . .

[enrique.ramirez]

@taylor.gardner2, for the toolchain, go to TOOLS section and download the one with the name “Bootlin Toolchain gcc 11.3”

Regards,
-Enrique

[taylor.gardner2]

Ok, I downloaded the toolchain and extracted the package. I see the CROSS_COMPILE path in that directory structure now. That part makes sense.

I’ve also downloaded the Driver Package (BSP) because that package contains the nvbuild.sh and source_sync.sh scripts which are in the instructions for Kernel Customization that I showed a link for above. I’m trying to understand the connection between these 2 packages. Is there a connection? Maybe I’m confused between 2 or more things here?

[enrique.ramirez]

To build the Kernel you’ll need the Kernel sources and the toolchain which contains the tools to compile and link your objects.

The Kernel sources can be found, by downloading the “Driver Package (BSP) Sources” (you can see it on your picture).

Having the the sources and the toolchain, you can can run the the steps to build.