From 6cdd7597a2fbfc1572c1b0af23d3daf1cefa2de7 Mon Sep 17 00:00:00 2001 From: Marek Vasut Date: Fri, 19 Dec 2025 03:40:44 +0100 Subject: kbuild: Produce diff between base DT and U-Boot augmented DT if DEVICE_TREE_DEBUG=1 In case DEVICE_TREE_DEBUG is set, produce a diff between the base DT and DT with U-Boot extras, to show how much does the U-Boot DT differ from the base DT. This is particularly useful together with OF_UPSTREAM, to minimize the diff between upstream DTs and U-Boot DTs. This requires DTC 1.7.2 which does not resolve phandles when used in the 'dtc -I dts -O dts ...' mode. With older DTC, the diff is full of churn due to the resolved phandles. Example usage: $ make r8a779g3_sparrowhawk_defconfig && make DEVICE_TREE_DEBUG=1 $ cat ./dts/upstream/src/arm64/renesas/r8a779g3-sparrow-hawk.dtb.diff Signed-off-by: Marek Vasut --- scripts/Makefile.lib | 23 ++++++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-) (limited to 'scripts') diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index ebac649d39a..377a4700b94 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -424,6 +424,26 @@ ifeq ($(CONFIG_OF_LIBFDT_OVERLAY),y) DTC_FLAGS += -@ endif +# In case DEVICE_TREE_DEBUG is set, produce a diff between the base DT and +# DT with U-Boot extras, to show how much does the U-Boot DT differ from +# the base DT. This is particularly useful together with OF_UPSTREAM, to +# minimize the diff between upstream DTs and U-Boot DTs. +ifdef DEVICE_TREE_DEBUG +cmd_dtc_diff = \ + $(HOSTCC) -E $(dtc_cpp_flags) -I$(obj) -x assembler-with-cpp -o $(dtn-tmp) $< ; \ + $(DTC) -s -O dts -o $@.clean.dts -b 0 \ + -i $(dir $<) $(DTC_FLAGS) $(dtn-tmp) || \ + (echo "Check $(shell pwd)/$< for errors" && false); \ + $(DTC) -s -O dts -o $@.full.dts -b 0 \ + -i $(dir $<) -i $(u_boot_dtsi_loc) $(DTC_FLAGS) $(dtc-tmp) || \ + (echo "Check $(shell pwd)/$(pre-tmp) for errors" && false); \ + (diff -Naru $@.clean.dts $@.full.dts > $@.diff || true) + +dtn-tmp = $(subst $(comma),_,$(dot-target).dtn.tmp) +else +cmd_dtc_diff = true +endif + quiet_cmd_dtc = DTC $@ # Modified for U-Boot # Bring in any U-Boot-specific include at the end of the file @@ -438,7 +458,8 @@ cmd_dtc = mkdir -p $(dir ${dtc-tmp}) ; \ -d $(depfile).dtc.tmp $(dtc-tmp) || \ (echo "Check $(shell pwd)/$(pre-tmp) for errors" && false) \ ; \ - sed "s:$(pre-tmp):$(<):" $(depfile).pre.tmp $(depfile).dtc.tmp > $(depfile) + sed "s:$(pre-tmp):$(<):" $(depfile).pre.tmp $(depfile).dtc.tmp > $(depfile) ; \ + $(cmd_dtc_diff) dtsi_include_list_deps := $(addprefix $(u_boot_dtsi_loc),$(subst $(quote),,$(dtsi_include_list))) -- cgit v1.2.3