diff --git a/.circleci/config.yml b/.circleci/config.yml
index 28afafb006..451b790854 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -20,6 +20,7 @@ jobs:
 
             BUILDSYSTEM_TOOLCHAIN=(
               "cmake arm-clang"
+              "cmake arm-iar"
               "make aarch64-gcc"
               "make arm-gcc"
               "make msp430-gcc"
@@ -28,7 +29,27 @@ jobs:
               "cmake esp-idf"
             )
 
-            RESOURCE_LARGE='["nrf", "imxrt"]'
+            RESOURCE_LARGE='["nrf", "imxrt", "stm32f4", "stm32h7"]'
+
+            gen_build_entry() {
+              local build_system="$1"
+              local toolchain="$2"
+              local family="$3"
+              local resource_class="$4"
+
+              if [[ "$toolchain" == "esp-idf" ]]; then
+                echo "      - build-vm:" >> .circleci/config2.yml
+              else
+                echo "      - build:" >> .circleci/config2.yml
+              fi
+
+              echo "          matrix:" >> .circleci/config2.yml
+              echo "            parameters:" >> .circleci/config2.yml
+              echo "              build-system: ['$build_system']" >> .circleci/config2.yml
+              echo "              toolchain: ['$toolchain']" >> .circleci/config2.yml
+              echo "              family: $family" >> .circleci/config2.yml
+              echo "              resource_class: ['$resource_class']" >> .circleci/config2.yml
+            }
 
             for e in "${BUILDSYSTEM_TOOLCHAIN[@]}"; do
               e_arr=($e)
@@ -43,26 +64,14 @@ jobs:
               FAMILY=$(jq -n --argjson family "$FAMILY" --argjson resource "$RESOURCE_LARGE" '$family | map(select(IN($resource[]) | not))')
 
               if [[ $toolchain == esp-idf ]]; then
-                echo "      - build-vm:" >> .circleci/config2.yml
+                gen_build_entry "$build_system" "$toolchain" "$FAMILY" "large"
               else
-                echo "      - build:" >> .circleci/config2.yml
-              fi
-              echo "          matrix:" >> .circleci/config2.yml
-              echo "            parameters:" >> .circleci/config2.yml
-              echo "              build-system: ['$build_system']" >> .circleci/config2.yml
-              echo "              toolchain: ['$toolchain']" >> .circleci/config2.yml
-              echo "              family: $FAMILY" >> .circleci/config2.yml
-              #echo "              resource_class: ['medium+']" >> .circleci/config2.yml
+                gen_build_entry "$build_system" "$toolchain" "$FAMILY" "medium+"
 
-              # add large resources
-              if [ "$(echo $FAMILY_LARGE | jq 'length')" -gt 0 ]; then
-                echo "      - build:" >> .circleci/config2.yml
-                echo "          matrix:" >> .circleci/config2.yml
-                echo "            parameters:" >> .circleci/config2.yml
-                echo "              build-system: ['$build_system']" >> .circleci/config2.yml
-                echo "              toolchain: ['$toolchain']" >> .circleci/config2.yml
-                echo "              family: $FAMILY_LARGE" >> .circleci/config2.yml
-                echo "              resource_class: ['large']" >> .circleci/config2.yml
+                # add large resources if available
+                if [ "$(echo $FAMILY_LARGE | jq 'length')" -gt 0 ]; then
+                    gen_build_entry "$build_system" "$toolchain" "$FAMILY_LARGE" "large"
+                fi
               fi
             done
 
diff --git a/.circleci/config2.yml b/.circleci/config2.yml
index e811ef3ede..e6ae87e77f 100644
--- a/.circleci/config2.yml
+++ b/.circleci/config2.yml
@@ -16,7 +16,8 @@ commands:
               "arm-gcc": "https://github.com/xpack-dev-tools/arm-none-eabi-gcc-xpack/releases/download/v13.2.1-1.1/xpack-arm-none-eabi-gcc-13.2.1-1.1-linux-x64.tar.gz",
               "msp430-gcc": "http://software-dl.ti.com/msp430/msp430_public_sw/mcu/msp430/MSPGCC/9_2_0_0/export/msp430-gcc-9.2.0.50_linux64.tar.bz2",
               "riscv-gcc": "https://github.com/xpack-dev-tools/riscv-none-elf-gcc-xpack/releases/download/v13.2.0-2/xpack-riscv-none-elf-gcc-13.2.0-2-linux-x64.tar.gz",
-              "rx-gcc": "https://llvm-gcc-renesas.com/downloads/get.php?f=rx/8.3.0.202004-gnurx/gcc-8.3.0.202004-GNURX-ELF.run"
+              "rx-gcc": "https://llvm-gcc-renesas.com/downloads/get.php?f=rx/8.3.0.202004-gnurx/gcc-8.3.0.202004-GNURX-ELF.run",
+              "arm-iar": "https://updates.iar.com/FileStore/STANDARD/001/003/322/cxarm-9.60.3.deb"
             }'
             toolchain_url=$(echo $TOOLCHAIN_JSON | jq -r '.["<< parameters.toolchain >>"]')
 
@@ -38,18 +39,26 @@ commands:
             # download if folder does not exist (not cached)
             if [ ! -d ~/cache/<< parameters.toolchain >> ]; then
               mkdir -p ~/cache/<< parameters.toolchain >>
-              wget --progress=dot:giga $toolchain_url -O toolchain.tar.gz
               if [[ << parameters.toolchain >> == rx-gcc ]]; then
-                mv toolchain.tar.gz toolchain.run
+                wget --progress=dot:giga $toolchain_url -O toolchain.run
                 chmod +x toolchain.run
                 ./toolchain.run -p ~/cache/<< parameters.toolchain >>/gnurx -y
+              elif [[ << parameters.toolchain >> == arm-iar ]]; then
+                wget --progress=dot:giga $toolchain_url -O ~/cache/<< parameters.toolchain >>/toolchain.deb
               else
+                wget --progress=dot:giga $toolchain_url -O toolchain.tar.gz
                 tar -C ~/cache/<< parameters.toolchain >> -xaf toolchain.tar.gz
               fi
             fi
 
             # Add toolchain to PATH
-            echo "export PATH=$PATH:`echo ~/cache/<< parameters.toolchain >>/*/bin`" >> $BASH_ENV
+            if [[ << parameters.toolchain >> == arm-iar ]]; then
+              # Install IAR since we only cache deb file
+              sudo dpkg --ignore-depends=libusb-1.0-0 -i ~/cache/<< parameters.toolchain >>/toolchain.deb
+              echo "export PATH=$PATH:/opt/iar/cxarm/arm/bin" >> $BASH_ENV
+            else
+              echo "export PATH=$PATH:`echo ~/cache/<< parameters.toolchain >>/*/bin`" >> $BASH_ENV
+            fi
 
       - save_cache:
           name: Save Toolchain Cache
@@ -110,6 +119,9 @@ commands:
               # Toolchain option default is gcc
               if [ << parameters.toolchain >> == arm-clang ]; then
                 TOOLCHAIN_OPTION="--toolchain clang"
+              elif [ << parameters.toolchain >> == arm-iar ]; then
+                TOOLCHAIN_OPTION="--toolchain iar"
+                iccarm --version
               elif [ << parameters.toolchain >> == arm-gcc ]; then
                 TOOLCHAIN_OPTION="--toolchain gcc"
               fi
diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 283b720616..67482c748b 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -113,13 +113,12 @@ jobs:
   # Build IAR on HFP self-hosted
   # ---------------------------------------
   arm-iar:
-    if: github.repository_owner == 'hathach'
+    if: github.repository_owner == 'hathach' && github.event_name == 'push'
     needs: set-matrix
     runs-on: [self-hosted, Linux, X64, hifiphile]
     env:
       BUILD_ARGS: ${{ join(fromJSON(needs.set-matrix.outputs.json)['arm-iar'], ' ') }}
-      IAR_LMS_CLOUD_URL: https://license.cloud.iar.com
-      IAR_LMS_BEARER_TOKEN: ${{ secrets.IAR_LMS_BEARER_TOKEN }}
+      # IAR_LMS_BEARER_TOKEN: ${{ secrets.IAR_LMS_BEARER_TOKEN }}
     steps:
       - name: Clean workspace
         run: |
@@ -138,8 +137,3 @@ jobs:
 
       - name: Build
         run: python3 tools/build.py --one-per-family --toolchain iar $BUILD_ARGS
-
-      - name: Test on actual hardware (hardware in the loop)
-        if: github.event_name == 'pull_request'
-        run: |
-          python3 test/hil/hil_test.py hfp.json
diff --git a/.github/workflows/ci_set_matrix.py b/.github/workflows/ci_set_matrix.py
index 78fcac68a3..410508246f 100755
--- a/.github/workflows/ci_set_matrix.py
+++ b/.github/workflows/ci_set_matrix.py
@@ -55,14 +55,6 @@ def set_matrix_json():
     for toolchain in toolchain_list:
         filtered_families = [family for family, supported_toolchain in family_list.items() if
                              toolchain in supported_toolchain]
-
-        # always add board in hfp.json for arm-iar
-        if toolchain == 'arm-iar':
-            with open('test/hil/hfp.json') as f:
-                hfp_data = json.load(f)
-            hfp_boards = [f"-b{board['name']}" for board in hfp_data['boards']]
-            filtered_families = filtered_families + hfp_boards
-
         matrix[toolchain] = filtered_families
 
     print(json.dumps(matrix))
diff --git a/.github/workflows/hil_test.yml b/.github/workflows/hil_test.yml
index c6e7f33b0b..bfa2b57047 100644
--- a/.github/workflows/hil_test.yml
+++ b/.github/workflows/hil_test.yml
@@ -58,7 +58,7 @@ jobs:
 
   # ---------------------------------------
   # Hardware in the loop (HIL)
-  # self-hosted running on an VM. For attached hardware checkout HIL_JSON
+  # self-hosted on local VM, for attached hardware checkout HIL_JSON
   # ---------------------------------------
   hil-tinyusb:
     if: github.repository_owner == 'hathach'
@@ -86,3 +86,41 @@ jobs:
         run: |
           ls cmake-build/
           python3 test/hil/hil_test.py ${{ env.HIL_JSON }}
+
+  # ---------------------------------------
+  # Hardware in the loop (HIL)
+  # self-hosted by HFP, build with IAR toolchain, for attached hardware checkout test/hil/hfp.json
+  # ---------------------------------------
+  hil-hfp:
+    if: github.repository_owner == 'hathach'
+    runs-on: [self-hosted, Linux, X64, hifiphile]
+    #env:
+    #  IAR_LMS_BEARER_TOKEN: ${{ secrets.IAR_LMS_BEARER_TOKEN }}
+    steps:
+      - name: Clean workspace
+        run: |
+          echo "Cleaning up previous run"
+          rm -rf "${{ github.workspace }}"
+          mkdir -p "${{ github.workspace }}"
+
+      - name: Toolchain version
+        run: iccarm --version
+
+      - name: Checkout TinyUSB
+        uses: actions/checkout@v4
+
+      - name: Get build boards
+        run: |
+          MATRIX_JSON=$(python test/hil/hil_ci_set_matrix.py test/hil/hfp.json)
+          BUILD_ARGS=$(echo $MATRIX_JSON | jq -r '.["arm-gcc"] | join(" ")')
+          echo "BUILD_ARGS=$BUILD_ARGS"
+          echo "BUILD_ARGS=$BUILD_ARGS" >> $GITHUB_ENV
+
+      - name: Get Dependencies
+        run: python3 tools/get_deps.py $BUILD_ARGS
+
+      - name: Build
+        run: python3 tools/build.py --toolchain iar $BUILD_ARGS
+
+      - name: Test on actual hardware (hardware in the loop)
+        run: python3 test/hil/hil_test.py hfp.json
diff --git a/tools/build.py b/tools/build.py
index 3a9239bc26..bbc98e9c48 100755
--- a/tools/build.py
+++ b/tools/build.py
@@ -109,7 +109,14 @@ def cmake_board(board, toolchain, build_flags_on):
         rcmd = run_cmd(f'cmake examples -B {build_dir} -G "Ninja" -DBOARD={board} -DCMAKE_BUILD_TYPE=MinSizeRel '
                        f'-DTOOLCHAIN={toolchain} {build_flags}')
         if rcmd.returncode == 0:
-            rcmd = run_cmd(f"cmake --build {build_dir}")
+            cmd = f"cmake --build {build_dir}"
+            # Due to IAR capability, limit parallel build to 4 (medium+) or 6 (large) docker
+            if toolchain == 'iar' and os.getenv('CIRCLECI'):
+                if 'large' in os.getenv('CIRCLE_JOB'):
+                    cmd += ' --parallel 6'
+                else:
+                    cmd += ' --parallel 4'
+            rcmd = run_cmd(cmd)
         ret[0 if rcmd.returncode == 0 else 1] += 1
 
     example = 'all'