ggml-webgpu: Enable NVIDIA self-hosted CI (#22976)

* Enabel nvidia ci for webgpu

* Address precision issues

* fix placement

* Relax more set_rows and div

* Try relaxing all f16

* formatting and naming

* Add comment explaining max_nmse_err logic

Added comment referencing pull request for clarification.

.github/workflows/build-self-hosted.yml

@@ -120,35 +120,34 @@ jobs:
           vulkaninfo --summary
           GG_BUILD_VULKAN=1 bash ./ci/run.sh ~/results/llama.cpp /mnt/llama.cpp
 
-  # TODO: investigate slight precision issues in some operations for test-backend-ops on the WebGPU backend.
-  #ggml-ci-nvidia-webgpu:
-  #  runs-on: [self-hosted, Linux, NVIDIA]
+  ggml-ci-nvidia-webgpu:
+    runs-on: [self-hosted, Linux, NVIDIA]
 
-  #  steps:
-  #    - name: Clone
-  #      id: checkout
-  #      uses: actions/checkout@v6
+    steps:
+      - name: Clone
+        id: checkout
+        uses: actions/checkout@v6
 
-  #    - name: Dawn Dependency
-  #      id: dawn-depends
-  #      run: |
-  #        DAWN_VERSION="v20260317.182325"
-  #        DAWN_OWNER="google"
-  #        DAWN_REPO="dawn"
-  #        DAWN_ASSET_NAME="Dawn-18eb229ef5f707c1464cc581252e7603c73a3ef0-ubuntu-latest-Release"
-  #        echo "Fetching release asset from https://github.com/google/dawn/releases/download/${DAWN_VERSION}/${DAWN_ASSET_NAME}.tar.gz"
-  #        curl -L -o artifact.tar.gz \
-  #          "https://github.com/google/dawn/releases/download/${DAWN_VERSION}/${DAWN_ASSET_NAME}.tar.gz"
-  #        mkdir dawn
-  #        tar -xvf artifact.tar.gz -C dawn --strip-components=1
+      - name: Dawn Dependency
+        id: dawn-depends
+        run: |
+          DAWN_VERSION="v20260317.182325"
+          DAWN_OWNER="google"
+          DAWN_REPO="dawn"
+          DAWN_ASSET_NAME="Dawn-18eb229ef5f707c1464cc581252e7603c73a3ef0-ubuntu-latest-Release"
+          echo "Fetching release asset from https://github.com/google/dawn/releases/download/${DAWN_VERSION}/${DAWN_ASSET_NAME}.tar.gz"
+          curl -L -o artifact.tar.gz \
+            "https://github.com/google/dawn/releases/download/${DAWN_VERSION}/${DAWN_ASSET_NAME}.tar.gz"
+          mkdir dawn
+          tar -xvf artifact.tar.gz -C dawn --strip-components=1
 
-  #    - name: Test
-  #      id: ggml-ci
-  #      run: |
-  #        GG_BUILD_WEBGPU=1 \
-  #        GG_BUILD_WEBGPU_DAWN_PREFIX="$GITHUB_WORKSPACE/dawn" \
-  #        GG_BUILD_WEBGPU_DAWN_DIR="$GITHUB_WORKSPACE/dawn/lib64/cmake/Dawn" \
-  #          bash ./ci/run.sh ~/results/llama.cpp /mnt/llama.cpp
+      - name: Test
+        id: ggml-ci
+        run: |
+          GG_BUILD_WEBGPU=1 \
+          GG_BUILD_WEBGPU_DAWN_PREFIX="$GITHUB_WORKSPACE/dawn" \
+          GG_BUILD_WEBGPU_DAWN_DIR="$GITHUB_WORKSPACE/dawn/lib64/cmake/Dawn" \
+            bash ./ci/run.sh ~/results/llama.cpp /mnt/llama.cpp
 
   # TODO: provision AMX-compatible machine
   #ggml-ci-cpu-amx: