nixos-config/modules/power.nix

{ config, pkgs, lib, ... }:

with rec {
  inherit (config) device deviceSpecific;
};
with deviceSpecific; {
  services.tlp = {
    enable = isLaptop;
    # New settings format in master branch nixpkgs
    # settings = {
    #   CPU_SCALING_GOVERNOR_ON_AC = "powersave";
    #   CPU_SCALING_GOVERNOR_ON_BAT = "powersave";
    #   CPU_HWP_ON_AC = "balance_performance";
    #   CPU_HWP_ON_BAT = "balance_power";
    #   CPU_BOOST_ON_AC = 1;
    #   CPU_BOOST_ON_BAT = 0;
    #   SCHED_POWERSAVE_ON_AC = 0;
    #   SCHED_POWERSAVE_ON_BAT = 1;
    #   CPU_ENERGY_PERF_POLICY_ON_AC = "balance_performance";
    #   CPU_ENERGY_PERF_POLICY_ON_BAT = "balance_power";
    #   DISK_DEVICES = "\"nvme0n1 sda\"";
    #   DISK_APM_LEVEL_ON_AC = "\"255 254\"";
    #   DISK_APM_LEVEL_ON_BAT = "\"255 254\"";
    #   SATA_LINKPWR_ON_BAT = "\"med_power_with_dipm max_performance\"";
    #   SATA_LINKPWR_ON_AC = "\"med_power_with_dipm max_performance\"";
    # };
    extraConfig = ''
      # Recommended
      CPU_SCALING_GOVERNOR_ON_AC=powersave
      CPU_SCALING_GOVERNOR_ON_BAT=powersave
      CPU_HWP_ON_AC=balance_performance
      CPU_HWP_ON_BAT=balance_power
      CPU_BOOST_ON_AC=1
      CPU_BOOST_ON_BAT=0
      SCHED_POWERSAVE_ON_AC=0
      SCHED_POWERSAVE_ON_BAT=1
      CPU_ENERGY_PERF_POLICY_ON_AC=balance_performance
      CPU_ENERGY_PERF_POLICY_ON_BAT=balance_power
      DISK_DEVICES="nvme0n1 sda"
      DISK_APM_LEVEL_ON_AC="255 254"
      DISK_APM_LEVEL_ON_BAT="255 254"
      # To avoid filesystem corruption on btrfs formatted partitions
      SATA_LINKPWR_ON_BAT="med_power_with_dipm max_performance"
      SATA_LINKPWR_ON_AC="med_power_with_dipm max_performance"
    '';

  };

  services.undervolt = lib.mkIf (device == "Dell-Laptop") {
    enable = true;
    coreOffset = "-120";
    gpuOffset = "-54";
  };
}