Check if we can skip toolchain build

.github/workflows/hi3516ev200_matrix.yml

@@ -17,10 +17,16 @@ on:
        - '**.md'
   workflow_dispatch:
 
+env:
+  RELEASES: https://github.com/OpenIPC/firmware/releases/download/latest
+  REPO_NAME: ${{ github.event.repository.name }}
+
 jobs:
   toolchain:
     name: Toolchain
     runs-on: ubuntu-latest
+    env:
+      NEEDED: true
 
     strategy:
       fail-fast: false
@@ -36,13 +42,19 @@ jobs:
         with:
           fetch-depth: 0  # OR "2" -> To retrieve the preceding commit.
 
-      - name: Determine toolchain name
+      - name: Determine toolchain name and can we skip build
         run: |
           make prepare
           TOOLNAME=$(make BOARD=unknown_unknown_${{ matrix.platform }}_openipc toolname)
           echo "TOOLNAME=$TOOLNAME" >> $GITHUB_ENV
+          CHECK=$(curl -o /dev/null --silent -Iw '%{http_code}' \
+            ${RELEASES}/${TOOLNAME}.tgz)
+          if [ "$CHECK" != "404" ]; then
+            echo "NEEDED=false" >> $GITHUB_ENV
+          fi
 
       - name: Install build dependencies
+        if: env.NEEDED
         run: |
           make install-deps
           #mkdir -p tmp
@@ -55,12 +67,13 @@ jobs:
           fi
 
       - name: Free disk space
-        if: ${{ !env.ACT }}
+        if: ${{ !env.ACT && env.NEEDED }}
         run: |
           sudo apt clean
           docker rmi $(docker image ls -aq)
 
       - name: Build Buildroot SDK
+        if: env.NEEDED
         run: |
           HEAD_TAG=$(git tag --points-at HEAD)
           GIT_HASH=$(git rev-parse --short $GITHUB_SHA)
@@ -87,13 +100,14 @@ jobs:
           echo "SDK_PATH=$SDK_PATH" >> $GITHUB_ENV
 
       - uses: actions/upload-artifact@v3
+        if: ${{ (env.ACT || github.event_name == 'pull_request') && env.NEEDED }}
         with:
           name: '${{ env.TOOLNAME }}.tgz'
           path: ${{ env.SDK_PATH }}
           retention-days: 1
 
       - name: Create release
-        if: ${{ !env.ACT && github.event_name != 'pull_request' }}
+        if: ${{ !env.ACT && github.event_name != 'pull_request' && env.NEEDED }}
         uses: actions/create-release@v1
         continue-on-error: true
         env:
@@ -105,7 +119,7 @@ jobs:
           prerelease: ${{ env.PRERELEASE }}
 
       - name: Upload SDK to release
-        if: ${{ !env.ACT && github.event_name != 'pull_request' }}
+        if: ${{ !env.ACT && github.event_name != 'pull_request' && env.NEEDED }}
         uses: svenstaro/upload-release-action@v2
         with:
           repo_token: ${{ secrets.GITHUB_TOKEN }}
@@ -204,6 +218,7 @@ jobs:
           echo "TOOLNAME=$TOOLNAME" >> $GITHUB_ENV
 
       - uses: actions/download-artifact@v3
+        if: ${{ (env.ACT || github.event_name == 'pull_request') }}
         with:
           name: '${{ env.TOOLNAME }}.tgz'
 
@@ -225,6 +240,10 @@ jobs:
           CONF_PATH=$(find . -name "${BOARD}_defconfig")
 
           echo Using $TOOLNAME
+          if [ ! -f "$TOOLNAME.tgz" ];
+            wget ${RELEASES}/${TOOLNAME}.tgz
+          fi
+
           set -x
           echo "BR2_TOOLCHAIN_EXTERNAL=y" >> $CONF_PATH
           echo "BR2_TOOLCHAIN_EXTERNAL_CUSTOM=y" >> $CONF_PATH