From 11d204a9c4fa5b562b2588af9326d1ee2319481c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Vladim=C3=ADr=20=C4=8Cun=C3=A1t?= <vcunat@gmail.com>
Date: Fri, 22 Mar 2019 13:59:48 +0100
Subject: [PATCH] nixos docs: improve GPU driver documentation

I'm not 100% sure about the incompatibility lines,
but I believe it's better to discourage these anyway.
If you find better information, feel free to amend...

The 32-bit thing is completely GPU-agnostic, so I can't see why we had
it separately for proprietary drivers and missing for the rest.
---
 nixos/doc/manual/configuration/x-windows.xml | 30 +++++++++-----------
 nixos/modules/services/x11/xserver.nix       |  7 ++++-
 2 files changed, 20 insertions(+), 17 deletions(-)

diff --git a/nixos/doc/manual/configuration/x-windows.xml b/nixos/doc/manual/configuration/x-windows.xml
index e7d66f391f5..3bcb288b5eb 100644
--- a/nixos/doc/manual/configuration/x-windows.xml
+++ b/nixos/doc/manual/configuration/x-windows.xml
@@ -35,8 +35,8 @@
  </para>
  <para>
   NixOS’s default <emphasis>display manager</emphasis> (the program that
-  provides a graphical login prompt and manages the X server) is LightDM. You can
-  select an alternative one by picking one of the following lines:
+  provides a graphical login prompt and manages the X server) is LightDM. You
+  can select an alternative one by picking one of the following lines:
 <programlisting>
 <xref linkend="opt-services.xserver.displayManager.sddm.enable"/> = true;
 <xref linkend="opt-services.xserver.displayManager.slim.enable"/> = true;
@@ -59,9 +59,16 @@
 <screen>
 # systemctl start display-manager.service
 </screen>
+ </para>
+ <para>
+  On 64-bit systems, if you want OpenGL for 32-bit programs such as in Wine,
+  you should also set the following:
+<programlisting>
+<xref linkend="opt-hardware.opengl.driSupport32Bit"/> = true;
+</programlisting>
  </para>
  <simplesect xml:id="sec-x11-graphics-cards-nvidia">
-  <title>NVIDIA Graphics Cards</title>
+  <title>Proprietary NVIDIA drivers</title>
   <para>
    NVIDIA provides a proprietary driver for its graphics cards that has better
    3D performance than the X.org drivers. It is not enabled by default because
@@ -71,6 +78,7 @@
 </programlisting>
    Or if you have an older card, you may have to use one of the legacy drivers:
 <programlisting>
+<xref linkend="opt-services.xserver.videoDrivers"/> = [ "nvidiaLegacy390" ];
 <xref linkend="opt-services.xserver.videoDrivers"/> = [ "nvidiaLegacy340" ];
 <xref linkend="opt-services.xserver.videoDrivers"/> = [ "nvidiaLegacy304" ];
 <xref linkend="opt-services.xserver.videoDrivers"/> = [ "nvidiaLegacy173" ];
@@ -78,16 +86,9 @@
    You may need to reboot after enabling this driver to prevent a clash with
    other kernel modules.
   </para>
-  <para>
-   On 64-bit systems, if you want full acceleration for 32-bit programs such as
-   Wine, you should also set the following:
-<programlisting>
-<xref linkend="opt-hardware.opengl.driSupport32Bit"/> = true;
-</programlisting>
-  </para>
  </simplesect>
  <simplesect xml:id="sec-x11--graphics-cards-amd">
-  <title>AMD Graphics Cards</title>
+  <title>Proprietary AMD drivers</title>
   <para>
    AMD provides a proprietary driver for its graphics cards that has better 3D
    performance than the X.org drivers. It is not enabled by default because
@@ -99,11 +100,8 @@
    other kernel modules.
   </para>
   <para>
-   On 64-bit systems, if you want full acceleration for 32-bit programs such as
-   Wine, you should also set the following:
-<programlisting>
-<xref linkend="opt-hardware.opengl.driSupport32Bit"/> = true;
-</programlisting>
+   Note: for recent AMD GPUs you most likely want to keep either the defaults
+   or <literal>"amdgpu"</literal> (both free).
   </para>
  </simplesect>
  <simplesect xml:id="sec-x11-touchpads">
diff --git a/nixos/modules/services/x11/xserver.nix b/nixos/modules/services/x11/xserver.nix
index c4d5b6a9cde..e767b0eda31 100644
--- a/nixos/modules/services/x11/xserver.nix
+++ b/nixos/modules/services/x11/xserver.nix
@@ -246,7 +246,7 @@ in
         default = [ "ati" "cirrus" "vesa" "vmware" "modesetting" ];
         example = [
           "ati_unfree" "amdgpu" "amdgpu-pro"
-          "nv" "nvidia" "nvidiaLegacy340" "nvidiaLegacy304"
+          "nv" "nvidia" "nvidiaLegacy390" "nvidiaLegacy340" "nvidiaLegacy304"
         ];
         # TODO(@oxij): think how to easily add the rest, like those nvidia things
         relatedPackages = concatLists
@@ -259,6 +259,11 @@ in
           The names of the video drivers the configuration
           supports. They will be tried in order until one that
           supports your card is found.
+          Don't combine those with "incompatible" OpenGL implementations,
+          e.g. free ones (mesa-based) with proprietary ones.
+
+          For unfree "nvidia*", the supported GPU lists are on
+          https://www.nvidia.com/object/unix.html
         '';
       };