image: introduce DEVICE_DTC_FLAGS and DEVICE_DTCO_FLAGS

Handle compiling device tree overlay blobs separate to allow for
overlays being compiled with different parameters, mostly to safe
space.
Allow defining DEVICE_DTC_FLAGS and DEVICE_DTCO_FLAGS as per-device
parameters to be passed to dtc. Previously some boards directly used
DTC_FLAGS in their build recipe which then also affected other boards.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>

include/image.mk

@@ -146,7 +146,7 @@ endif
 
 
 # Disable noisy checks by default as in upstream
-DTC_FLAGS += \
+DTC_WARN_FLAGS := \
   -Wno-unit_address_vs_reg \
   -Wno-simple_bus_reg \
   -Wno-unit_address_format \
@@ -159,6 +159,9 @@ DTC_FLAGS += \
   -Wno-graph_port \
   -Wno-unique_unit_address
 
+DTC_FLAGS += $(DTC_WARN_FLAGS)
+DTCO_FLAGS += $(DTC_WARN_FLAGS)
+
 define Image/pad-to
 	dd if=$(1) of=$(1).new bs=$(2) conv=sync
 	mv $(1).new $(1)
@@ -174,7 +177,7 @@ endef
 # $(2) target dtb file
 # $(3) extra CPP flags
 # $(4) extra DTC flags
-define Image/BuildDTB
+define Image/BuildDTB/sub
 	$(TARGET_CROSS)cpp -nostdinc -x assembler-with-cpp \
 		$(DTS_CPPFLAGS) \
 		-I$(DTS_DIR) \
@@ -183,12 +186,20 @@ define Image/BuildDTB
 		-undef -D__DTS__ $(3) \
 		-o $(2).tmp $(1)
 	$(LINUX_DIR)/scripts/dtc/dtc -O dtb \
-		-i$(dir $(1)) $(DTC_FLAGS) $(4) \
+		-i$(dir $(1)) $(4) \
 	$(if $(CONFIG_HAS_DT_OVERLAY_SUPPORT),-@) \
 		-o $(2) $(2).tmp
 	$(RM) $(2).tmp
 endef
 
+define Image/BuildDTB
+	$(call Image/BuildDTB/sub,$(1),$(2),$(3),$(DTC_FLAGS) $(DEVICE_DTC_FLAGS) $(4))
+endef
+
+define Image/BuildDTBO
+	$(call Image/BuildDTB/sub,$(1),$(2),$(3),$(DTCO_FLAGS) $(DEVICE_DTCO_FLAGS) $(4))
+endef
+
 define Image/mkfs/jffs2/sub-raw
 	$(STAGING_DIR_HOST)/bin/mkfs.jffs2 \
 		$(2) \
@@ -400,6 +411,8 @@ define Device/Init
   DEVICE_DTS_LOADADDR :=
   DEVICE_DTS_OVERLAY :=
   DEVICE_FDT_NUM :=
+  DEVICE_DTC_FLAGS :=
+  DEVICE_DTCO_FLAGS :=
   SOC :=
 
   BOARD_NAME :=
@@ -422,9 +435,9 @@ endef
 DEFAULT_DEVICE_VARS := \
   DEVICE_NAME KERNEL KERNEL_INITRAMFS KERNEL_INITRAMFS_IMAGE KERNEL_SIZE \
   CMDLINE UBOOTENV_IN_UBI KERNEL_IN_UBI BLOCKSIZE PAGESIZE SUBPAGESIZE \
-  VID_HDR_OFFSET UBINIZE_OPTS UBINIZE_PARTS MKUBIFS_OPTS DEVICE_DTS \
-  DEVICE_DTS_CONFIG DEVICE_DTS_DELIMITER DEVICE_DTS_DIR DEVICE_DTS_OVERLAY \
-  DEVICE_DTS_LOADADDR \
+  VID_HDR_OFFSET UBINIZE_OPTS UBINIZE_PARTS MKUBIFS_OPTS DEVICE_DTC_FLAGS \
+  DEVICE_DTCO_FLAGS DEVICE_DTS DEVICE_DTS_CONFIG DEVICE_DTS_DELIMITER \
+  DEVICE_DTS_DIR DEVICE_DTS_OVERLAY DEVICE_DTS_LOADADDR \
   DEVICE_FDT_NUM DEVICE_IMG_PREFIX SOC BOARD_NAME UIMAGE_MAGIC UIMAGE_NAME \
   UIMAGE_TIME SUPPORTED_DEVICES IMAGE_METADATA KERNEL_ENTRY KERNEL_LOADADDR \
   UBOOT_PATH IMAGE_SIZE \
@@ -557,10 +570,10 @@ define Device/Build/dtb
 endef
 
 define Device/Build/dtbo
-  ifndef BUILD_DTS_$(1)
-  BUILD_DTS_$(1) := 1
+  ifndef BUILD_DTSO_$(1)
+  BUILD_DTSO_$(1) := 1
   $(KDIR)/image-$(1).dtbo: FORCE
-	$(call Image/BuildDTB,$(strip $(2))/$(strip $(3)).dtso,$$@)
+	$(call Image/BuildDTBO,$(strip $(2))/$(strip $(3)).dtso,$$@)
 
   image_prepare: $(KDIR)/image-$(1).dtbo
   endif