How to build for ARM Tegra devices

info

Only Orin (sm_87) / Jetpack 6 and later Tegra devices are supported.

A separate Tegra variant is needed for CUDA 12.9 only. Starting with CUDA 13.0 and Jetpack 7, new Tegra devices are SBSA-compliant, so building a separate variant for Tegra devices is not required.

The CUDA compiler toolchain treats Tegra ARM (aarch64) and SBSA ARM (sbsa) as separate compilation targets, and device code compiled for one is not interchangeable with the other, so one build cannot service all variants. The arm-variant package allows end-users to select which variant of the CUDA ARM packages is installed into their environment.

To build for both SBSA ARM and Tegra ARM devices, make the following changes to your feedstock:

Add the arm-variant package to the recipe's build environment(s) to constrain the CUDA compiler toolchain.

For example:

v0 (meta.yaml)
v1 (recipe.yaml)

# A fake selector may also be needed for conda-build to pick up arm_variant_type as a variant
# [arm_variant_type]

requirements:
  build:
    - {{ compiler('cuda') }}
    - arm-variant * {{ arm_variant_type }}  # [linux and aarch64 and cuda_compiler_version != "None"]

requirements:
  build:
    - ${{ compiler('cuda') }}
    - if: linux and aarch64 and cuda_compiler_version != "None"
      then: arm-variant * ${{ arm_variant_type }}

note

Building with the arm-variant package will produce overlinking warnings from conda-build. This is expected and may be safely ignored.

Add the arm_variant_type.yaml migrator to the .ci_support/migrations folder.

You can download this migrator from https://github.com/conda-forge/conda-forge-pinning-feedstock/tree/main/recipe/migrations. It adds the arm_variant_type variable to the build matrix for CUDA 12.9 only and sets a higher c_stdlib_version.
Enable the ARM platform for linux in conda-forge.yml. Tegra variants may be built on linux-aarch64 runners or cross-compiled from linux-64 runners using the usual cross-compiling setup.

For example:
```
provider:
  linux_aarch64: default
```