Prepare for portable build process

Makefile

@@ -1,28 +1,38 @@
-SRC=$(wildcard src/*.c)
-INCLUDE=$(wildcard src/include/*.h)
-OBJ=$(patsubst src/%.c,build/%.rel,$(SRC))
+# Parameter for current board
+BOARD?=galp3-c
 
-all: build/ec.rom
+# Set build directory
+BUILD=build/$(BOARD)
 
+# Default target - build the board's EC firmware
+all: $(BUILD)/ec.rom
+
+# Target to remove build artifacts
 clean:
 	rm -rf build
 
-sim: build/ec.rom
-	cargo run \
-		--release \
-		--manifest-path ecsim/Cargo.toml \
-		--no-default-features \
-		-- $<
+# Include common source
+SRC=$(wildcard src/*.c)
+INCLUDE=$(wildcard src/include/*.h)
 
-build/ec.rom: build/ec.ihx
-	mkdir -p build
-	makebin -p < $< > $@
+# Include the board's source
+BOARD_DIR=src/board/$(BOARD)
+SRC+=$(wildcard $(BOARD_DIR)/*.c)
+INCLUDE+=$(wildcard $(BOARD_DIR)/include/*.h)
+include $(BOARD_DIR)/board.mk
 
-build/ec.ihx: $(OBJ)
-	mkdir -p build
-	sdcc -mmcs51 -o $@ $^
+# The board will define the embedded controller
+# Include the embedded controller's source
+EC_DIR=src/ec/$(EC)
+SRC+=$(wildcard $(EC_DIR)/*.c)
+INCLUDE+=$(wildcard $(EC_DIR)/include/*.h)
+include $(EC_DIR)/ec.mk
 
-build/%.rel: src/%.c $(INCLUDE)
-	mkdir -p build
-	cd build && \
-	sdcc -mmcs51 -c ../$<
+# The EC will define the architecture
+# Include the architecture's source
+ARCH_DIR=src/arch/$(ARCH)
+SRC+=$(wildcard $(ARCH_DIR)/*.c)
+INCLUDE+=$(wildcard $(ARCH_DIR)/include/*.h)
+include $(ARCH_DIR)/arch.mk
+
+# The architecture defines build targets, no more is required

src/arch/8051/arch.mk

@@ -0,0 +1,25 @@
+CC=sdcc -mmcs51
+OBJ=$(patsubst src/%.c,$(BUILD)/%.rel,$(SRC))
+
+# Run EC rom in simulator
+sim: $(BUILD)/ec.rom
+	cargo run \
+		--release \
+		--manifest-path ecsim/Cargo.toml \
+		--no-default-features \
+		-- $<
+
+# Convert from Intel Hex format to binary
+$(BUILD)/ec.rom: $(BUILD)/ec.ihx
+	@mkdir -p $(@D)
+	makebin -p < $< > $@
+
+# Link object files into Intel Hex format
+$(BUILD)/ec.ihx: $(OBJ)
+	@mkdir -p $(@D)
+	$(CC) -o $@ $^
+
+# Compile C files into object files
+$(BUILD)/%.rel: src/%.c $(INCLUDE)
+	@mkdir -p $(@D)
+	$(CC) -o $@ -c $<

src/board/galp3-c/board.mk

@@ -0,0 +1 @@
+EC=it8587e

src/ec/it8587e/ec.mk

@@ -0,0 +1 @@
+ARCH=8051