Rework Makefile a bit.

rename TARGET to BOARD (fix #55)
use .INTERMEDIATE trick to avoid building multiple times (fix #52)
Don't touch build/*/.config if we don't have to (fix #51)

Makefile

@@ -5,9 +5,12 @@ build		:= $(pwd)/build
 config		:= $(pwd)/build
 
 # Currently supported targets are x230, chell and qemu
-TARGET		?= x230
+BOARD		?= x230
 
-all: $(TARGET).rom
+all: $(BOARD).rom
+
+# Disable all built in rules
+.SUFFIXES:
 
 
 # Bring in all of the module definitions;
@@ -15,7 +18,9 @@ all: $(TARGET).rom
 # as part of creating the Heads firmware image.
 include modules/*
 
-all: $(modules)
+# These will be built via their intermediate targets
+# This increases the build time, so it is commented out for now
+#all: $(foreach m,$(modules),$m.intermediate)
 
 define prefix =
 $(foreach _, $2, $1$_)
@@ -68,8 +73,14 @@ define define_module =
   endif
 
   # Copy our stored config file into the unpacked directory
-  $(build)/$($1_dir)/.config: config/$($1_config) $(build)/$($1_dir)/.canary
-	cp "$$<" "$$@"
+  ifdef $1_config
+    $(build)/$($1_dir)/.config: config/$($1_config) $(build)/$($1_dir)/.canary
+	cp -a "$$<" "$$@"
+  else
+    $(build)/$($1_dir)/.config: $(build)/$($1_dir)/.canary
+	touch "$$@"
+  endif
+  
 
   # Use the module's configure variable to build itself
   $(build)/$($1_dir)/.configured: \
@@ -79,14 +90,18 @@ define define_module =
 	touch "$$@"
 
   # Build the target after any dependencies
-  $(call outputs,$1): \
-		$(build)/$($1_dir)/.configured \
-		$(call outputs,$($1_depends))
-	make -C "$(build)/$($1_dir)" $($1_target)
+  $(call outputs,$1): $1.intermediate
 
   # Short hand target for the module
-  $1: $(call outputs,$1)
+  #$1: $(call outputs,$1)
 
+  # Target for all of the outputs, which depend on their dependent modules
+$1.intermediate: \
+		$(build)/$($1_dir)/.configured \
+		$(foreach d,$($1_depends),$d.intermediate)
+	make -C "$(build)/$($1_dir)" $($1_target)
+
+.INTERMEDIATE: $1.intermediate
 endef
 
 $(foreach _, $(modules), $(eval $(call define_module,$_)))
@@ -208,6 +223,8 @@ initrd.cpio: $(initrd_bins) $(initrd_libs) initrd_lib_install
 		echo "$@: Unchanged"; \
 		rm "$@.tmp"; \
 	fi
+
+initrd.intermediate: initrd.cpio
 	
 
 # populate the coreboot initrd image from the one we built.

config/coreboot-blobs.config

@@ -1 +0,0 @@
-# nothing

config/kexec.config

@@ -1 +0,0 @@
-# nothing

config/mbedtls.config

@@ -1 +0,0 @@
-# nothing

config/qrencode.config

@@ -1 +0,0 @@
-# nothing

config/tpmtotp.config

@@ -1 +0,0 @@
-# nothing

config/xen.config

@@ -1 +0,0 @@
-# Nothing

modules/coreboot

@@ -11,15 +11,15 @@ coreboot_repo := https://github.com/osresearch/coreboot
 
 # Coreboot builds are specialized on a per-target basis.
 # The builds are done in a per-target subdirectory
-coreboot_config := coreboot-$(TARGET).config
+#coreboot_config := coreboot-$(TARGET).config
 
 coreboot_configure := \
-	make oldconfig obj=./$(TARGET) DOTCONFIG=../../config/coreboot-$(TARGET).config
+	make oldconfig obj=./$(BOARD) DOTCONFIG=../../config/coreboot-$(BOARD).config
 
 coreboot_target := \
-	obj=./$(TARGET) DOTCONFIG=../../config/coreboot-$(TARGET).config -j 8
+	obj=./$(BOARD) DOTCONFIG=../../config/coreboot-$(BOARD).config -j 8
 
-coreboot_output := $(TARGET)/coreboot.rom
+coreboot_output := $(BOARD)/coreboot.rom
 
 
 # hack to force a build dependency on the cross compiler

modules/cryptsetup

@@ -7,5 +7,4 @@ cryptsetup_url := https://www.kernel.org/pub/linux/utils/cryptsetup/v1.7/cryptse
 cryptsetup_hash := dbb35dbf5f0c1749168c86c913fe98e872247bfc8425314b494c2423e7e43342
 
 cryptsetup_configure := ./configure
-cryptsetup_config := cryptsetup.config
 cryptsetup_output := 

modules/kexec

@@ -8,4 +8,3 @@ kexec_hash := cc7b60dad0da202004048a6179d8a53606943062dd627a2edba45a8ea3a85135
 
 kexec_configure := ./configure
 kexec_output := build/sbin/kexec
-kexec_config := kexec.config

modules/mbedtls

@@ -11,4 +11,3 @@ mbedtls_libraries := \
 
 mbedtls_configure :=
 mbedtls_target := SHARED=1
-mbedtls_config := mbedtls.config

modules/qrencode

@@ -8,4 +8,3 @@ qrencode_hash := e794e26a96019013c0e3665cb06b18992668f352c5553d0a553f5d144f7f2a7
 
 qrencode_output := .libs/libqrencode.so.$(qrencode_version)
 qrencode_configure := ./configure --without-tools
-qrencode_config := qrencode.config

modules/tpmtotp

@@ -42,4 +42,3 @@ tpmtotp_libraries := \
 	libtpm/libtpm.so \
 
 tpmtotp_configure := 
-tpmtotp_config := tpmtotp.config

modules/xen

@@ -11,4 +11,3 @@ xen_hash := 02badfce9a037bd1bd4a94210c1f6b85467746216c71795805102b514bcf1fc4
 xen_output := xen.gz
 xen_configure := 
 xen_target := -j 8
-xen_config := xen.config