nixpkgs/nixos/modules/hardware/corectrl.nix

{
  config,
  pkgs,
  lib,
  ...
}:
let
  inherit (lib)
    mkEnableOption
    mkIf
    mkOption
    mkPackageOption
    ;

  cfg = config.programs.corectrl;
in
{
  options.programs.corectrl = {
    enable = mkEnableOption ''
      CoreCtrl, a tool to overclock amd graphics cards and processors.
      Add your user to the corectrl group to run corectrl without needing to enter your password
    '';

    package = mkPackageOption pkgs "corectrl" {
      extraDescription = "Useful for overriding the configuration options used for the package.";
    };

    gpuOverclock = {
      enable = mkEnableOption ''
        GPU overclocking
      '';
      ppfeaturemask = mkOption {
        type = lib.types.str;
        default = "0xfffd7fff";
        example = "0xffffffff";
        description = ''
          Sets the `amdgpu.ppfeaturemask` kernel option.
          In particular, it is used here to set the overdrive bit.
          Default is `0xfffd7fff` as it is less likely to cause flicker issues.
          Setting it to `0xffffffff` enables all features.
        '';
      };
    };
  };

  config = mkIf cfg.enable {
    environment.systemPackages = [ cfg.package ];

    services.dbus.packages = [ cfg.package ];

    users.groups.corectrl = { };

    security.polkit.extraConfig = ''
      polkit.addRule(function(action, subject) {
          if ((action.id == "org.corectrl.helper.init" ||
               action.id == "org.corectrl.helperkiller.init") &&
              subject.local == true &&
              subject.active == true &&
              subject.isInGroup("corectrl")) {
                  return polkit.Result.YES;
          }
      });
    '';

    # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/gpu/drm/amd/include/amd_shared.h#n169
    # The overdrive bit
    boot.kernelParams = mkIf cfg.gpuOverclock.enable [
      "amdgpu.ppfeaturemask=${cfg.gpuOverclock.ppfeaturemask}"
    ];
  };

  meta.maintainers = with lib.maintainers; [
    artturin
    Scrumplex
  ];
}