add get-deps target

update ci to get-deps first

.github/workflows/build_arm.yml

@@ -67,6 +67,11 @@ jobs:
     - name: Setup Python
       uses: actions/setup-python@v3
 
+    - name: Install ARM GCC
+      uses: carlosperate/arm-none-eabi-gcc-action@v1
+      with:
+        release: '11.2-2022.02'
+
     - name: Checkout TinyUSB
       uses: actions/checkout@v3
 
@@ -86,10 +91,10 @@ jobs:
         echo >> $GITHUB_ENV PICO_SDK_PATH=~/pico-sdk
         git submodule update --init hw/mcu/raspberry_pi/Pico-PIO-USB
 
-    - name: Install ARM GCC
-      uses: carlosperate/arm-none-eabi-gcc-action@v1
-      with:
-        release: '11.2-2022.02'
+    - name: Get Dependencies
+      run: |
+        b=`find hw/bsp/${{ matrix.family }}/boards -depth -maxdepth 1 -type d -name '[^.]?*' -printf %f -quit`
+        make BOARD={b} get-deps
 
     - name: Build
       run: python3 tools/build_family.py ${{ matrix.family }}

docs/reference/getting_started.rst

@@ -50,7 +50,12 @@ Some TinyUSB examples also requires external submodule libraries in ``/lib`` suc
 
    $ git submodule update --init lib
 
-In addition, MCU driver submodule is also needed to provide low-level MCU peripheral's driver. Luckily, it will be fetched if needed when you run the ``make`` to build your board.
+In addition, MCU driver submodule is also needed to provide low-level MCU peripheral's driver. To download these depencies for your board, run the ``get-dpes`` as follow.
+
+.. code-block::
+
+   $ make BOARD=feather_nrf52840_express get-deps
+
 
 Some modules will also require a module-specific SDK (e.g. RP2040) or binary (e.g. Sony Spresense) to build examples.
 

examples/make.mk

@@ -45,11 +45,6 @@ else
   SRC_C += $(subst $(TOP)/,,$(wildcard $(TOP)/$(FAMILY_PATH)/*.c))
 endif
 
-# Fetch submodules depended by family
-fetch_submodule_if_empty = $(if $(wildcard $(TOP)/$1/*),,$(info $(shell git -C $(TOP) submodule update --init $1)))
-ifdef DEPS_SUBMODULES
-  $(foreach s,$(DEPS_SUBMODULES),$(call fetch_submodule_if_empty,$(s)))
-endif
 
 #-------------- Cross Compiler  ------------
 # Can be set by board, default to ARM GCC

examples/rules.mk

@@ -5,6 +5,7 @@
 # Set all as default goal
 .DEFAULT_GOAL := all
 
+# ---------------- GNU Make Start -----------------------
 # ESP32-Sx and RP2040 has its own CMake build system
 ifeq (,$(findstring $(FAMILY),esp32s2 esp32s3 rp2040))
 
@@ -141,7 +142,23 @@ $(BUILD)/obj/%_asm.o: %.S
 	@echo AS $(notdir $@)
 	@$(CC) -x assembler-with-cpp $(ASFLAGS) -c -o $@ $<
 
-endif # GNU Make
+endif
+
+.PHONY: clean
+clean:
+ifeq ($(CMDEXE),1)
+	rd /S /Q $(subst /,\,$(BUILD))
+else
+	$(RM) -rf $(BUILD)
+endif
+# ---------------- GNU Make End -----------------------
+
+# get depenecies
+.PHONY: get-deps
+get-deps:
+  ifdef DEPS_SUBMODULES
+	git -C $(TOP) submodule update --init $(DEPS_SUBMODULES)
+  endif
 
 size: $(BUILD)/$(PROJECT).elf
 	-@echo ''
@@ -152,14 +169,6 @@ size: $(BUILD)/$(PROJECT).elf
 linkermap: $(BUILD)/$(PROJECT).elf
 	@linkermap -v $<.map
 
-.PHONY: clean
-clean:
-ifeq ($(CMDEXE),1)
-	rd /S /Q $(subst /,\,$(BUILD))
-else
-	$(RM) -rf $(BUILD)
-endif
-
 # ---------------------------------------
 # Flash Targets
 # ---------------------------------------