Kbuild: Use dtc's -d (dependency) option
This hooks dtc into Kbuild's dependency system.
Thus, for example, "make dtbs" will rebuild tegra-harmony.dtb if only
tegra20.dtsi has changed yet tegra-harmony.dts has not. The previous
lack of this feature recently caused me to have very confusing "git
bisect" results.
For ARM, it's obvious what to add to $(targets). I'm not familiar enough
with other architectures to know what to add there. Powerpc appears to
already add various .dtb files into $(targets), but the other archs may
need something added to $(targets) to work.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
[mmarek: Dropped arch/c6x part to avoid merging commits from the middle
of the merge window]
Signed-off-by: Michal Marek <mmarek@suse.cz>
diff --git a/arch/arm/boot/Makefile b/arch/arm/boot/Makefile
index a1edfd5..816e91b 100644
--- a/arch/arm/boot/Makefile
+++ b/arch/arm/boot/Makefile
@@ -59,9 +59,11 @@
endif
+targets += $(dtb-y)
+
# Rule to build device tree blobs
-$(obj)/%.dtb: $(src)/dts/%.dts
- $(call cmd,dtc)
+$(obj)/%.dtb: $(src)/dts/%.dts FORCE
+ $(call if_changed_dep,dtc)
$(obj)/dtbs: $(addprefix $(obj)/, $(dtb-y))
diff --git a/arch/microblaze/boot/Makefile b/arch/microblaze/boot/Makefile
index 4c4e58e..0c796cf 100644
--- a/arch/microblaze/boot/Makefile
+++ b/arch/microblaze/boot/Makefile
@@ -53,6 +53,6 @@
DTC_FLAGS := -p 1024
$(obj)/%.dtb: $(src)/dts/%.dts FORCE
- $(call cmd,dtc)
+ $(call if_changed_dep,dtc)
clean-files += *.dtb simpleImage.*.unstrip linux.bin.ub
diff --git a/arch/openrisc/boot/Makefile b/arch/openrisc/boot/Makefile
index 98ca185..0995835 100644
--- a/arch/openrisc/boot/Makefile
+++ b/arch/openrisc/boot/Makefile
@@ -11,5 +11,5 @@
#DTC_FLAGS ?= -p 1024
-$(obj)/%.dtb: $(src)/dts/%.dts
- $(call cmd,dtc)
+$(obj)/%.dtb: $(src)/dts/%.dts FORCE
+ $(call if_changed_dep,dtc)
diff --git a/arch/powerpc/boot/Makefile b/arch/powerpc/boot/Makefile
index c26200b..5e1f0d5 100644
--- a/arch/powerpc/boot/Makefile
+++ b/arch/powerpc/boot/Makefile
@@ -334,8 +334,8 @@
$(call if_changed,wrap,treeboot-$*,,$(obj)/$*.dtb)
# Rule to build device tree blobs
-$(obj)/%.dtb: $(src)/dts/%.dts
- $(call cmd,dtc)
+$(obj)/%.dtb: $(src)/dts/%.dts FORCE
+ $(call if_changed_dep,dtc)
# If there isn't a platform selected then just strip the vmlinux.
ifeq (,$(image-y))
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 2ce2e21..00c368c 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -264,7 +264,7 @@
$(call cmd,dt_S_dtb)
quiet_cmd_dtc = DTC $@
-cmd_dtc = $(objtree)/scripts/dtc/dtc -O dtb -o $@ -b 0 $(DTC_FLAGS) $<
+cmd_dtc = $(objtree)/scripts/dtc/dtc -O dtb -o $@ -b 0 $(DTC_FLAGS) -d $(depfile) $<
# Bzip2
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