build: add directory-oriented make workflows

firmware/boards/board.mk

@@ -0,0 +1,69 @@
+override SHELL := /bin/sh
+override MAKEFLAGS += --no-print-directory
+
+.DEFAULT_GOAL := help
+.DELETE_ON_ERROR:
+
+override CARGO := cargo
+override CARGO_FLAGS := --locked --offline
+override DFU_UTIL := dfu-util
+
+override EMBEDDED_TARGET := thumbv7em-none-eabihf
+override PACKAGE := kaptan-$(BOARD)
+override TARGET_DIR := ../../target/$(EMBEDDED_TARGET)/release
+override CREATE_IMAGE := ../../scripts/create-dfu-image.sh
+
+override DFU_DEVICE := 0483:df11
+override DFU_ALT := 0
+override DFU_ADDRESS := 0x08000000:leave
+
+override PRIMARY_GOAL := $(firstword $(MAKECMDGOALS))
+
+run:
+	@exec python3 ../../../scripts/make-argv.py exec run $(CARGO) build --release \
+		$(CARGO_FLAGS) -p $(PACKAGE) --target $(EMBEDDED_TARGET)
+	$(CREATE_IMAGE) $(TARGET_DIR)/$(PACKAGE)
+
+_build:
+	$(CARGO) build --release $(CARGO_FLAGS) -p $(PACKAGE) \
+		--target $(EMBEDDED_TARGET)
+	$(CREATE_IMAGE) $(TARGET_DIR)/$(PACKAGE)
+
+flash: _build
+	@printf '%s\n' 'Flashing $(TARGET_DIR)/$(PACKAGE).bin to $(DFU_DEVICE)'
+	@exec python3 ../../../scripts/make-argv.py exec flash \
+		$(DFU_UTIL) --device $(DFU_DEVICE) --alt $(DFU_ALT) \
+		--dfuse-address $(DFU_ADDRESS) \
+		--download $(TARGET_DIR)/$(PACKAGE).bin
+
+ifeq ($(PRIMARY_GOAL),run)
+
+.PHONY: run
+
+# Application arguments may also look like Make goals. The run recipe recovers
+# their exact boundaries from the original invocation.
+.DEFAULT:
+	@:
+
+else
+
+ifeq ($(PRIMARY_GOAL),flash)
+
+.PHONY: flash _build
+
+.DEFAULT:
+	@:
+
+else
+
+.PHONY: help run flash _build
+
+help:
+	@printf '%s\n' 'Usage: make firmware/boards/$(BOARD) -- <cargo build arguments...>' '' \
+		'       make firmware/boards/$(BOARD) flash -- <dfu-util arguments...>' '' \
+		'With no arguments, this board is built and packaged.' \
+		'The flash target builds, packages, and writes this board over DFU.'
+
+endif
+
+endif