srx-platform-nix/modules/hardware/rpi4.nix

{ lib, pkgs, ... }:
{
  boot = {
    loader = {
      grub.enable = lib.mkForce false;
      generic-extlinux-compatible.enable = lib.mkForce true;
    };
    initrd = {
      availableKernelModules = [
        "genet"
        "xhci_pci"
        "usbhid"
        "usb_storage"
      ];
      kernelModules = [ ];
    };
  };

  hardware = {
    enableRedistributableFirmware = lib.mkForce false;
    firmware = [ pkgs.raspberrypiWirelessFirmware ];
  };

  environment.systemPackages = with pkgs; [
    libraspberrypi
    raspberrypi-eeprom
    rpiboot
  ];

  nix = {
    extraOptions = ''
      min-free = ${toString (100 * 1024 * 1024)}
      max-free = ${toString (1024 * 1024 * 1024)}
    '';
    settings.max-jobs = lib.mkDefault 4;
  };
}