hosts/framenix: reduce power consumption with proper PPD CPU + ABM

- patch PPD to properly set the powersave level for the spu as well
- enable adaptive backlight management at lowest level

inspired by 1cbeaa156b/packages/default.nix

hosts/framenix/default.nix

@@ -38,8 +38,13 @@ in
     }
     ];
 
+  boot.kernelParams = [ 
     # temporary workaround for white flickering graphics artefacts
-  boot.kernelParams = [ "amdgpu.sg_display=0" ];
+    "amdgpu.sg_display=0"
+    # powersave
+    "amd_pstate=active"
+    "amdgpu.abmlevel=1" # adaptive backlight management
+  ];
 
   boot.loader = {
     systemd-boot.enable = true;

packages/default.nix

@@ -1,2 +1,12 @@
 final: prev: {
+  power-profiles-daemon = prev.power-profiles-daemon.overrideAttrs (old: {
+    patches = [
+      # patch for AMD pstate CPUs
+      (final.fetchpatch {
+        url = "https://gitlab.freedesktop.org/upower/power-profiles-daemon/-/merge_requests/127.patch";
+        sha256 = "sha256-CneqixlpZx9iZ0PM5MFIutsvnqKrLlM7FHOHUA/MK6g=";
+      })
+    ];
+  });
+
 }