kbuild: centralize .dts->.dtb rule

All architectures that use cmd_dtc do so in almost the same way. Create
a central build rule to avoid duplication. The one difference is that
most current uses of dtc build $(obj)/%.dtb from $(src)/dts/%.dts rather
than building the .dtb in the same directory as the .dts file. This
difference will be eliminated arch-by-arch in future patches.

MIPS is the exception here; it already uses the exact same rule as the
new common rule, so the duplicate is removed in this patch to avoid any
conflict. arch/mips changes courtesy of Ralf Baechle.

Update Documentation/kbuild to remove the explicit call to cmd_dtc from
the example, now that the rule exists in a centralized location.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-arm-kernel@lists.infradead.org
Cc: Olof Johansson <olof@lixom.net>
Cc: Russell King <linux@arm.linux.org.uk>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: linux@lists.openrisc.net
Cc: Aurelien Jacquiot <a-jacquiot@ti.com>
Cc: linux-c6x-dev@linux-c6x.org
Cc: Mark Salter <msalter@redhat.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: microblaze-uclinux@itee.uq.edu.au
Cc: Chris Zankel <chris@zankel.net>
Cc: linux-xtensa@linux-xtensa.org
Cc: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Rob Herring <rob.herring@calxeda.com>

diff --git a/Documentation/kbuild/makefiles.txt b/Documentation/kbuild/makefiles.txt
index ec9ae67086911efa3022b912f1a30bfeb3aea976..14c3f4f1b61773bc660f1f73a1c57e438f2ef975 100644 (file)
--- a/Documentation/kbuild/makefiles.txt
+++ b/Documentation/kbuild/makefiles.txt
@@ -1175,15 +1175,16 @@ When kbuild executes, the following steps are followed (roughly):
        in an init section in the image. Platform code *must* copy the
        blob to non-init memory prior to calling unflatten_device_tree().
 
-       Example:
-               #arch/x86/platform/ce4100/Makefile
-               clean-files := *dtb.S
+       To use this command, simply add *.dtb into obj-y or targets, or make
+       some other target depend on %.dtb
 
-               DTC_FLAGS := -p 1024
-               obj-y += foo.dtb.o
+       A central rule exists to create $(obj)/%.dtb from $(src)/%.dts;
+       architecture Makefiles do no need to explicitly write out that rule.
 
-               $(obj)/%.dtb: $(src)/%.dts
-                       $(call cmd,dtc)
+       Example:
+               targets += $(dtb-y)
+               clean-files += *.dtb
+               DTC_FLAGS ?= -p 1024
 
 --- 6.8 Custom kbuild commands
 

diff --git a/arch/mips/cavium-octeon/Makefile b/arch/mips/cavium-octeon/Makefile
index bc96e2908f14436616083cf3706fd0dddf718d6a..6e927cf20df243a8e42f353baa54d5d9d74ef74e 100644 (file)
--- a/arch/mips/cavium-octeon/Makefile
+++ b/arch/mips/cavium-octeon/Makefile
@@ -24,9 +24,6 @@ DTB_FILES = $(patsubst %.dts, %.dtb, $(DTS_FILES))
 
 obj-y += $(patsubst %.dts, %.dtb.o, $(DTS_FILES))
 
-$(obj)/%.dtb: $(src)/%.dts FORCE
-       $(call if_changed_dep,dtc)
-
 # Let's keep the .dtb files around in case we want to look at them.
 .SECONDARY:  $(addprefix $(obj)/, $(DTB_FILES))
 

diff --git a/arch/mips/lantiq/dts/Makefile b/arch/mips/lantiq/dts/Makefile
index 674fca45f72d65e9278e4d21c57dd6c2f8ebc0e5..6fa72dd641b299739f75568d5ad4c469852c49a4 100644 (file)
--- a/arch/mips/lantiq/dts/Makefile
+++ b/arch/mips/lantiq/dts/Makefile
@@ -1,4 +1 @@
 obj-$(CONFIG_DT_EASY50712) := easy50712.dtb.o
-
-$(obj)/%.dtb: $(obj)/%.dts
-       $(call if_changed,dtc)

diff --git a/arch/mips/netlogic/dts/Makefile b/arch/mips/netlogic/dts/Makefile
index 67ae3fe296f0c0d3158fececd4149840b078b508..d117d46413aa29d9b03806935c3d206f0e4f6b29 100644 (file)
--- a/arch/mips/netlogic/dts/Makefile
+++ b/arch/mips/netlogic/dts/Makefile
@@ -1,4 +1 @@
 obj-$(CONFIG_DT_XLP_EVP) := xlp_evp.dtb.o
-
-$(obj)/%.dtb: $(obj)/%.dts
-       $(call if_changed,dtc)

diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 0be6f110cce79be4c4acd2f4dbf4ac2ce7d24057..bdf42fdf64c9adb0095a1ff0ad3437499d0ba87c 100644 (file)
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -266,6 +266,9 @@ $(obj)/%.dtb.S: $(obj)/%.dtb
 quiet_cmd_dtc = DTC     $@
 cmd_dtc = $(objtree)/scripts/dtc/dtc -O dtb -o $@ -b 0 $(DTC_FLAGS) -d $(depfile) $<
 
+$(obj)/%.dtb: $(src)/%.dts FORCE
+       $(call if_changed_dep,dtc)
+
 # Bzip2
 # ---------------------------------------------------------------------------