From c9f84afd83ef3a270673e915e825492eabebbbac Mon Sep 17 00:00:00 2001
From: Daniel Langbein <daniel@systemli.org>
Date: Tue, 6 Feb 2024 22:00:01 +0100
Subject: [PATCH] disable intel gup

---
 NixOS.md                           | 5 +++++
 hosts/yodaGaming/configuration.nix | 7 +++++++
 modules/steam.nix                  | 2 ++
 3 files changed, 14 insertions(+)

diff --git a/NixOS.md b/NixOS.md
index 1b51e85..565fb9d 100644
--- a/NixOS.md
+++ b/NixOS.md
@@ -692,9 +692,14 @@ Video acceleration:
   - Video Decode and Presentation API for Unix (VDPAU).
   - Verifying: `vdpauinfo`. https://wiki.archlinux.org/title/Hardware_video_acceleration#Verifying_VDPAU
 
+Verify video driver in use:
+- `lspci -k | grep -EA3 'VGA|3D|Display'`. Example: `Kernel driver in use: amdgpu`
+
 Verification in general:
 - Encode a video or play a game and watch AMD GPU usage with `radeontop`.
 
+Configuration example to disable integrated GUP: See [./hosts/yodaGaming/configuration.nix](./hosts/yodaGaming/configuration.nix)
+
 Configuration example for an AMD GPU (https://github.com/tolgaerok/nixos-kde/blob/main/core/gpu/amd/default.nix): See [./modules/gpu-amd.nix](./modules/gpu-amd.nix)
 
 ## Additional resources
diff --git a/hosts/yodaGaming/configuration.nix b/hosts/yodaGaming/configuration.nix
index 94c6801..47e9d48 100644
--- a/hosts/yodaGaming/configuration.nix
+++ b/hosts/yodaGaming/configuration.nix
@@ -48,6 +48,13 @@
   # BIOS
   boot.loader.grub.devices = ["/dev/disk/by-id/ata-Samsung_SSD_840_EVO_250GB_S1DBNSAF715594P"];
 
+  # Disable onboard Intel GPU
+  #   https://github.com/NixOS/nixos-hardware/blob/master/common/gpu/intel/disable.nix
+  #   https://discourse.nixos.org/t/fully-disabling-the-nvidia-dgpu-on-an-optimus-laptop/29686/6?u=langfingaz
+  boot.blacklistedKernelModules = [ "i915" ];
+  boot.kernelParams = [ "i915.modeset=0" ];
+
+
   # List all available kernel versions:
   #   `nix repl` -> `:l <nixpkgs>` -> `pkgs.linuxPackages` and press `TAB`
   # Default.
diff --git a/modules/steam.nix b/modules/steam.nix
index c6787c6..b392154 100644
--- a/modules/steam.nix
+++ b/modules/steam.nix
@@ -1,5 +1,7 @@
 { config, pkgs, ... }:
 {
+  # https://wiki.archlinux.org/title/steam#See_also
+
   # flatpak install com.valvesoftware.Steam
 
   # Launching Steam with Flatpak might warn you about installing the steam-devices package to add support for some gamepads.