From 8073aa4e473ba5d748e9946c90497eb3d9464777 Mon Sep 17 00:00:00 2001
From: Antoine Viallon <antoine@lesviallon.fr>
Date: Wed, 12 Oct 2022 19:22:13 +0200
Subject: [PATCH] [Power] Init power related config. Also add cpuVendor
 setting.

---
 default.nix |   1 +
 general.nix |   7 +++
 power.nix   | 169 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 177 insertions(+)
 create mode 100644 power.nix

diff --git a/default.nix b/default.nix
index cade0b9..8107d80 100644
--- a/default.nix
+++ b/default.nix
@@ -13,6 +13,7 @@
     ./hardening.nix
     ./hardware.nix
     ./laptop.nix
+    ./power.nix
     ./overlays.nix
     ./optimizations.nix
     ./non-persistence.nix
diff --git a/general.nix b/general.nix
index 3700765..4cbfd4c 100644
--- a/general.nix
+++ b/general.nix
@@ -51,6 +51,13 @@ in
       description = "Number of physical threads of the machine";
       type = with types; nullOr ints.positive;
     };
+
+    cpuVendor = mkOption {
+      default = null;
+      example = "amd";
+      description = "Vendor of you CPU. Either AMD or Intel";
+      type = types.str;
+    };
     
     cpuArch = mkOption {
       default = "x86-64";
diff --git a/power.nix b/power.nix
new file mode 100644
index 0000000..6744198
--- /dev/null
+++ b/power.nix
@@ -0,0 +1,169 @@
+{ config, pkgs, lib, myLib, ... }:
+with lib;
+let
+  generalCfg = config.aviallon.general;
+  cfg = config.aviallon.power;
+  undervoltType = with types; nullOr (addCheck int (x: (x < 0 && x > -200)));
+in {
+  options.aviallon.power = {
+    enable = mkOption {
+      default = true;
+      example = false;
+      type = types.bool;
+      description = "Wether to enable power related tuning";
+    };
+    /*policy = mkOption {
+      default = "performance";
+      example = "efficiency";
+      description = "What to optimize towards";
+      type = types.either [ "performance" "efficiency" ];
+    };*/
+    powerLimit = {
+      enable = mkEnableOption "power limiting";
+      ac = {
+        cpu = mkOption {
+          default = null;
+          type = types.nullOr types.int;
+          description = "Power limit when on AC. Set to null for unlimited.";
+          example = 35;
+        };
+        cpuBoost = mkOption {
+          default = null;
+          type = types.nullOr types.int;
+          description = "Boost power limit when on AC. Set to null for unlimited.";
+          example = 65;
+        };
+      };
+      battery = {
+        cpu = mkOption {
+          default = null;
+          type = types.nullOr types.int;
+          description = "Power limit when on battery. Set to null for unlimited.";
+          example = 15;
+        };
+        cpuBoost = mkOption {
+          default = null;
+          type = types.nullOr types.int;
+          description = "Boost power limit when on battery. Set to null for unlimited.";
+          example = 35;
+        };
+      };
+    };
+    temperature = {
+      enable = mkEnableOption "Temperature limitting";
+      ac = {
+        cpu = mkOption {
+          default = null;
+          type = types.nullOr types.int;
+          description = "Temperature limit when on AC.";
+          example = 100;
+        };
+      };
+      battery = {
+        cpu = mkOption {
+          default = null;
+          type = types.nullOr types.int;
+          description = "Temperature limit when on battery.";
+          example = 60;
+        };
+      };
+    };
+    undervolt.cpu = {
+      enable = mkEnableOption "CPU undervolting. Unstability may be caused when using this option.";
+      coreOffset = mkOption {
+        default = null;
+        example = -25;
+        description = "CPU core offset in mV";
+        type = undervoltType;
+      };
+      cacheOffset = mkOption {
+        default = cfg.undervolt.cpu.coreOffset;
+        example = -25;
+        description = "Cache offset in mV";
+        type = undervoltType;
+      };
+      iGPUOffset = mkOption {
+        default = null;
+        example = -15;
+        description = "iGPU offset in mV";
+        type = undervoltType;
+      };
+    };
+    undervolt.gpu = {
+      enable = mkEnableOption "GPU undervolting.";
+    };
+  };
+  config = mkIf cfg.enable {
+    systemd.targets.ac-power = {
+      description = "Target is active when AC is plugged-in.";
+      wantedBy = [ "multi-user.target" ];
+      conflicts = [ "battery-power.target" ];
+      unitConfig = {
+        ConditionACPower = true;
+      };
+    };
+    
+    systemd.targets.battery-power = {
+      description = "Target is active when power is drawn from a battery.";
+      wantedBy = [ "multi-user.target" ];
+      conflicts = [ "ac-power.target" ];
+    };
+
+    services.udev.extraRules = ''
+      KERNEL=="AC*", SUBSYSTEM=="power_supply", ATTR{online}=="0", RUN+="${pkgs.systemd}/bin/systemctl stop ac-power.target"
+      KERNEL=="AC*", SUBSYSTEM=="power_supply", ATTR{online}=="1", RUN+="${pkgs.systemd}/bin/systemctl start ac-power.target"
+      
+      KERNEL=="BAT*", SUBSYSTEM=="power_supply", ATTR{status}=="Discharging", RUN+="${pkgs.systemd}/bin/systemctl start battery-power.target"
+      KERNEL=="BAT*", SUBSYSTEM=="power_supply", ATTR{status}=="Charging", RUN+="${pkgs.systemd}/bin/systemctl stop battery-power.target"
+    '';
+  
+    systemd.services.undervolt-intel = {
+      script = ""
+        + "${pkgs.undervolt}/bin/undervolt"
+        + (optionalString (! isNull cfg.undervolt.cpu.coreOffset ) " --core ${toString cfg.undervolt.cpu.coreOffset}")
+        + (optionalString (! isNull cfg.undervolt.cpu.cacheOffset ) " --cache ${toString cfg.undervolt.cpu.cacheOffset}")
+        + (optionalString (! isNull cfg.undervolt.cpu.iGPUOffset ) " --gpu ${toString cfg.undervolt.cpu.iGPUOffset}")
+      ;
+      serviceConfig = {
+        RemainAfterExit = true;
+      };
+      wantedBy = [ "multi-user.target" ];
+      description = "Undervolt Intel CPUs with supported firmware.";
+      enable = cfg.undervolt.cpu.enable && (generalCfg.cpuVendor == "intel");
+    };
+
+    systemd.services.intel-powerlimit-ac = {
+      script = "${pkgs.undervolt}/bin/undervolt"
+        + optionalString (! isNull cfg.powerLimit.ac.cpu ) " --power-limit-long ${toString cfg.powerLimit.ac.cpu} 28"
+        + optionalString (! isNull cfg.powerLimit.ac.cpuBoost ) " --power-limit-short ${toString cfg.powerLimit.ac.cpuBoost} 0.1"
+        + optionalString (! isNull cfg.temperature.ac.cpu ) " --temp ${toString cfg.temperature.ac.cpu}"
+      ;
+      unitConfig = {
+        ConditionACPower = true;
+      };
+      serviceConfig = {
+        RemainAfterExit = true;
+      };
+      wantedBy = [ "multi-user.target" "ac-power.target" ];
+      description = "Set power limit of Intel CPUs with supported firmware. AC mode.";
+      partOf = [ "ac-power.target" ];
+      enable = (cfg.powerLimit.enable || cfg.temperature.enable) && (generalCfg.cpuVendor == "intel");
+    };
+    
+    systemd.services.intel-powerlimit-battery = {
+      script = "${pkgs.undervolt}/bin/undervolt"
+        + optionalString (! isNull cfg.powerLimit.battery.cpu ) " --power-limit-long ${toString cfg.powerLimit.battery.cpu} 28"
+        + optionalString (! isNull cfg.powerLimit.battery.cpuBoost ) " --power-limit-short ${toString cfg.powerLimit.battery.cpuBoost} 0.1"
+        + optionalString (! isNull cfg.temperature.battery.cpu ) " --temp ${toString cfg.temperature.battery.cpu}"
+      ;
+      serviceConfig = {
+        RemainAfterExit = true;
+      };
+      wantedBy = [ "multi-user.target" "battery-power.target" ];
+      description = "Set power limit of Intel CPUs with supported firmware. Battery mode.";
+      partOf = [ "battery-power.target" ];
+      enable = (cfg.powerLimit.enable || cfg.temperature.enable) && (generalCfg.cpuVendor == "intel");
+    };
+    
+  };
+}