nixos/hosts/citadel/default.nix

{
  inputs,
  lib,
  pkgs,
  config,
  configVars,
  ...
}: let
  # Disko setup
  fsType = "btrfs"; # one of ext4 or btrfs. Use btrfs if using impermanence
  dev = "/dev/nvme0n1"; # depends on target hardware
  encrypted = true; # currrently only applies to btrfs
  btrfsMountDevice =
    if encrypted
    then "/dev/mapper/crypted"
    else "/dev/root_vg/root";
  user = "sam";
  impermanence = true;
  pieholeIp = configVars.networking.addresses.piehole.ip;
  gatewayIp = configVars.networking.addresses.gateway.ip;
in {
  imports = [
    # Create users for this host
    ../common/users/${user}

    # Disk configuration
    inputs.disko.nixosModules.disko
    (import ../common/disks {
      device = dev;
      impermanence = impermanence;
      fsType = fsType;
      encrypted = encrypted;
    })

    # Impermanence
    (import ../common/disks/btrfs/impermanence.nix {
      btrfsMountDevice = btrfsMountDevice;
      lib = lib;
    })

    # Import core options
    ./hardware-configuration.nix
    ../common/core

    # Import optional options
    ../common/optional/persistence.nix
    ../common/optional/pipewire.nix
    ../common/optional/openssh.nix
    ../common/optional/dwm.nix
    ../common/optional/nfs-mounts/media.nix
    ../common/optional/nfs-mounts/homeshare.nix
    ../common/optional/nfs-mounts/photos.nix
    ../common/optional/printing.nix
    ../common/optional/backlight.nix
    ../common/optional/xmodmap-arrow-remaps.nix
    ../common/optional/nix-ld.nix
    ../common/optional/gaming.nix
  ];

  boot = {
    blacklistedKernelModules = ["snd_hda_intel" "snd_soc_skl"];
    kernelModules = ["iwlwifi"];
    initrd.kernelModules = ["thinkpad-acpi" "acpi-call"];
    kernelPackages = pkgs.linuxPackagesFor pkgs.linux_latest;
    extraModulePackages = [
      config.boot.kernelPackages.acpi_call
    ];
    loader = {
      systemd-boot.enable = true;
      efi.canTouchEfiVariables = true;
      timeout = 3;
    };
  };

  swapDevices = [
    {
      device = "/.swapvol/swapfile";
      size = 32 * 1024;
    }
  ];

  services = {
    libinput.touchpad.accelSpeed = "0.5";
    xserver = {
      xkb.options = "caps:swapescape";
      dpi = 196;
      upscaleDefaultCursor = true;
      # FIXME this doesnt work for some reason
      #     displayManager.sessionCommands = pkgs.writeShellScriptBin "key-remaps" ''
      #     ${pkgs.xorg.xmodmap}/bin/xmodmap -e "keycode 64 = Mode_switch"
      #     ${pkgs.xorg.xmodmap}/bin/xmodmap -e "keycode 43 = h H Left H"
      #     ${pkgs.xorg.xmodmap}/bin/xmodmap -e "keycode 44 = j J Down J"
      #     ${pkgs.xorg.xmodmap}/bin/xmodmap -e "keycode 45 = k K Up K"
      #     ${pkgs.xorg.xmodmap}/bin/xmodmap -e "keycode 46 = l L Right L"
      # '';
    };
  };

  # fix cpu throttling on Lenovo Thinkpad
  # see: https://github.com/erpalma/throttled
  services.throttled.enable = true;

  environment.variables = {
    GDK_SCALE = "2.2";
    GDK_DPI_SCALE = "0.8";
    _JAVA_OPTIONS = "-Dsun.java2d.uiScale=2.2";
    QT_AUTO_SCREEN_SCALE_FACTOR = "1";
    XCURSOR_SIZE = "64";
  };

  environment.systemPackages = [
    pkgs.linuxKernel.packages.linux_zen.cpupower
    pkgs.lm_sensors
  ];

  services.tlp = {
    enable = true;
    settings = {
      CPU_SCALING_GOVERNOR_ON_AC = "ondemand";
      CPU_SCALING_GOVERNOR_ON_BAT = "powersave";

      START_CHARGE_THRESH_BAT0 = 60;
      STOP_CHARGE_THRESH_BAT0 = 85;
    };
  };

  hardware = {
    bluetooth = {
      enable = true;
      powerOnBoot = true;
    };
    enableRedistributableFirmware = true;
    firmware = [
      pkgs.sof-firmware
    ];
  };

  # nvidia
  hardware.opengl = {
    enable = true;
  };

  services.xserver.videoDrivers = ["nvidia"];

  hardware.nvidia = {
    prime = {
      offload = {
        enable = true;
        enableOffloadCmd = true;
      };
      intelBusId = "PCI:0:2:0";
      nvidiaBusId = "PCI:1:0:0";
    };
    nvidiaPersistenced = true;
    modesetting.enable = true;
    powerManagement.enable = true;
    powerManagement.finegrained = true;
    open = false;
    nvidiaSettings = true;
    # FIXME issue with stable nvidia driver and latest linux kernel
    # use mkDriver to specify newer nvidia driver that is compatible
    # see: https://github.com/NixOS/nixpkgs/issues/341844#issuecomment-2351075413
    # and https://discourse.nixos.org/t/builder-for-nvidia-x11-550-78-6-10-drv-failed-with-exit-code-2/49360/32
    package = config.boot.kernelPackages.nvidiaPackages.mkDriver {
      version = "555.58.02";
      sha256_64bit = "sha256-xctt4TPRlOJ6r5S54h5W6PT6/3Zy2R4ASNFPu8TSHKM=";
      sha256_aarch64 = "sha256-wb20isMrRg8PeQBU96lWJzBMkjfySAUaqt4EgZnhyF8=";
      openSha256 = "sha256-8hyRiGB+m2hL3c9MDA/Pon+Xl6E788MZ50WrrAGUVuY=";
      settingsSha256 = "sha256-ZpuVZybW6CFN/gz9rx+UJvQ715FZnAOYfHn5jt5Z2C8=";
      persistencedSha256 = "sha256-a1D7ZZmcKFWfPjjH1REqPM5j/YLWKnbkP9qfRyIyxAw=";
    };
  };
  # https://bbs.archlinux.org/viewtopic.php?id=297276 for NVreg_EnableGpuFirmware fix
  # https://discourse.nixos.org/t/how-to-use-nvidia-prime-offload-to-run-the-x-server-on-the-integrated-board/9091/15
  #  for udev rules to disable dGPU when not in use
  boot.extraModprobeConfig = ''
    options nvidia NVreg_EnableGpuFirmware=0
  '';
  services.udev.extraRules = ''
    # Remove NVIDIA USB xHCI Host Controller devices, if present
    ACTION=="add", SUBSYSTEM=="pci", ATTR{vendor}=="0x10de", ATTR{class}=="0x0c0330", ATTR{remove}="1"

    # Remove NVIDIA USB Type-C UCSI devices, if present
    ACTION=="add", SUBSYSTEM=="pci", ATTR{vendor}=="0x10de", ATTR{class}=="0x0c8000", ATTR{remove}="1"

    # Remove NVIDIA Audio devices, if present
    ACTION=="add", SUBSYSTEM=="pci", ATTR{vendor}=="0x10de", ATTR{class}=="0x040300", ATTR{remove}="1"

    # Enable runtime PM for NVIDIA VGA/3D controller devices on driver bind
    ACTION=="bind", SUBSYSTEM=="pci", ATTR{vendor}=="0x10de", ATTR{class}=="0x030000", TEST=="power/control", ATTR{power/control}="auto"
    ACTION=="bind", SUBSYSTEM=="pci", ATTR{vendor}=="0x10de", ATTR{class}=="0x030200", TEST=="power/control", ATTR{power/control}="auto"

    # Disable runtime PM for NVIDIA VGA/3D controller devices on driver unbind
    ACTION=="unbind", SUBSYSTEM=="pci", ATTR{vendor}=="0x10de", ATTR{class}=="0x030000", TEST=="power/control", ATTR{power/control}="on"
    ACTION=="unbind", SUBSYSTEM=="pci", ATTR{vendor}=="0x10de", ATTR{class}=="0x030200", TEST=="power/control", ATTR{power/control}="on"
  '';

  networking = {
    hostName = "citadel";
    networkmanager.enable = true;
    enableIPv6 = false;
    nameservers = ["${pieholeIp}" "${gatewayIp}" "8.8.8.8"];
  };

  services.libinput.enable = true;
}