ROCm support

NixOS.md

@@ -899,7 +899,7 @@ Usually most of this should work out of the box on NixOS.
 Vulkan:
 - Verification:
   - If `vulkaninfo` returns information about your GPU, Vulkan is working. https://wiki.archlinux.org/title/Vulkan#Verification
-    - `nix-shell -p vulkan-tools --run vulkaninfo`
+    - `nix-shell -p vulkan-tools --run 'vulkaninfo --summary'`
   - Run `vkcube` (X11) or `vkcube-wayland` (Wayland). It should view a spinning 3D cube and output e.g. `Selected GPU 0: AMD Radeon Graphics (RADV RENOIR)`
     - `nix-shell -p vulkan-tools --run vkcube-wayland`
 
@@ -922,7 +922,7 @@ Video acceleration:
   - Verifying: `vdpauinfo`. https://wiki.archlinux.org/title/Hardware_video_acceleration#Verifying_VDPAU
     - `nix-shell -p vdpauinfo --run vdpauinfo`
 
-GPGPU (General-purpose computing on graphics processing units):
+GPGPU (General-purpose computing on graphics processing units, https://wiki.archlinux.org/title/GPGPU):
   - OpenCL
     - Verification using `clinfo`
       - `nix-shell -p clinfo --run 'clinfo -l'`
@@ -930,10 +930,19 @@ GPGPU (General-purpose computing on graphics processing units):
       - `nix-shell -p clinfo --run clinfo`
         - This output is more verbose.
         - `Number of platforms` should be >= 1
+  - ROCm
+    - Verify using `nix-shell -p  rocmPackages.rocminfo --run rocminfo`
+    - ROCm gfx version
+      - `nix-shell -p "rocmPackages.rocminfo" --run "rocminfo" | grep "gfx"`
+        - Example: `Name: gfx90c`
+        - According to this website this is in section `GCN GFX9 (Vega)`
+          - https://discuss.linuxcontainers.org/t/rocm-and-pytorch-on-amd-apu-or-gpu-ai/19743#environment-variables-4
+          - https://llvm.org/docs/AMDGPUUsage.html#processors
 
 Verify video driver in use:
 - `lspci -k | grep -EA3 'VGA|3D|Display'`. Example: `Kernel driver in use: amdgpu`
   - `nix-shell -p pciutils --run 'lspci -k | grep -EA3 "VGA|3D|Display"'`
+- `nix-shell -p inxi pciutils mesa-demos --run 'inxi -Gzxx'`. Example: `driver: amdgpu`
 
 Verification in general:
 - Encode a video or play a game and watch AMD GPU usage with `radeontop`.

modules/gpu-amd.nix

@@ -39,6 +39,11 @@ in
     };
   };
 
+  nixpkgs.config = {
+    # Supported by most modern AMD GPUs.
+    rocmSupport = true;
+  };
+
   environment.variables = {
     # VDPAU does not pick up correct driver. Thus, we need to configure it manually.
     # https://wiki.archlinux.org/title/Hardware_video_acceleration#Failed_to_open_VDPAU_backend