Cross Compilation

Ghaf is targeted at a range of devices and form factors that support different instruction set architectures (ISA). Many small form-factor edge devices are not powerful enough to compile the needed applications or OSs that run on them. As the most common ISA used in desktops and servers is x_86, this will generally require that the code is cross-compiled for target ISA e.g. AArch64 or RISC-V.

NixOS and Nixpkgs have good support for cross-compilation, however, there are still some that can not be compiled in this way.

Cross-Compilation for Microchip Icicle Kit (RISCV64)

An SD image for the Microchip Icicle Kit can be cross-compiled from an x86 machine. To generate the release or debug an SD image run the following command:

nix build .#packages.riscv64-linux.microchip-icicle-kit-<release/debug>

Future Cross-Compilation Support

This will involve working with upstream package maintainers to ensure that the packages are cross-compilation aware. This will be addressed on a package-by-package basis.

binfmt Emulated Build

binfmt allows running different ISA on a development machine. This is achieved by running the target binary in an emulator such as QEMU or in a VM. So while not cross-compiled it can enable development for some embedded device configurations.

To enable binfmt, we recommend to set the following in your host systems configuration.nix:

boot.binfmt.emulatedSystems = [
  "riscv64-linux"
  "aarch64-linux"
];

In addition, it is recommended to enable KVM support with either

boot.kernelModules = [ "kvm-amd" ];

boot.kernelModules = [ "kvm-intel" ];

depending on whether your development host is running AMD or Intel processor.