ARM: convert build of appended dtb zImage to list of dtbs

Allow CONFIG_BUILD_ARM_APPENDED_DTB_IMAGE_NAMES to specify
a space separated list of dtbs to append to the zImage,
and name the resulting file zImage-dtb

Change-Id: Ied5d0bafbd1d01fc1f109c15c4283de7029903c9
Signed-off-by: Colin Cross <ccross@android.com>

arch/arm/Kconfig

@@ -1857,16 +1857,16 @@ config BUILD_ARM_APPENDED_DTB_IMAGE
 	bool "Build a concatenated zImage/dtb by default"
 	depends on OF
 	help
-	  Enabling this option will cause a concatenated zImage and DTB to
+	  Enabling this option will cause a concatenated zImage and list of
-	  be built by default (instead of a standalone zImage.)  The image
+	  DTBs to be built by default (instead of a standalone zImage.)
-	  will built in arch/arm/boot/zImage-dtb.<dtb name>
+	  The image will built in arch/arm/boot/zImage-dtb
 
-config BUILD_ARM_APPENDED_DTB_IMAGE_NAME
+config BUILD_ARM_APPENDED_DTB_IMAGE_NAMES
-	string "Default dtb name"
+	string "Default dtb names"
 	depends on BUILD_ARM_APPENDED_DTB_IMAGE
 	help
-	  name of the dtb to append when building a concatenated
+	  Space separated list of names of dtbs to append when
-	  zImage/dtb.
+	  building a concatenated zImage-dtb.
 
 # Compressed boot loader in ROM.  Yes, we really want to ask about
 # TEXT and BSS so we preserve their values in the config files.

arch/arm/Makefile

@@ -297,7 +297,7 @@ libs-y				:= arch/arm/lib/ $(libs-y)
 ifeq ($(CONFIG_XIP_KERNEL),y)
 KBUILD_IMAGE := xipImage
 else ifeq ($(CONFIG_BUILD_ARM_APPENDED_DTB_IMAGE),y)
-KBUILD_IMAGE := zImage-dtb.$(CONFIG_BUILD_ARM_APPENDED_DTB_IMAGE_NAME)
+KBUILD_IMAGE := zImage-dtb
 else
 KBUILD_IMAGE := zImage
 endif
@@ -348,6 +348,9 @@ ifeq ($(CONFIG_VDSO),y)
 	$(Q)$(MAKE) $(build)=arch/arm/vdso $@
 endif
 
+zImage-dtb: vmlinux scripts dtbs
+	$(Q)$(MAKE) $(build)=$(boot) MACHINE=$(MACHINE) $(boot)/$@
+
 # We use MRPROPER_FILES and CLEAN_FILES now
 archclean:
 	$(Q)$(MAKE) $(clean)=$(boot)

arch/arm/boot/.gitignore

@@ -4,3 +4,4 @@ xipImage
 bootpImage
 uImage
 *.dtb
+zImage-dtb

arch/arm/boot/Makefile

@@ -28,6 +28,14 @@ export ZRELADDR INITRD_PHYS PARAMS_PHYS
 
 targets := Image zImage xipImage bootpImage uImage
 
+DTB_NAMES := $(subst $\",,$(CONFIG_BUILD_ARM_APPENDED_DTB_IMAGE_NAMES))
+ifneq ($(DTB_NAMES),)
+DTB_LIST := $(addsuffix .dtb,$(DTB_NAMES))
+else
+DTB_LIST := $(dtb-y)
+endif
+DTB_OBJS := $(addprefix $(obj)/dts/,$(DTB_LIST))
+
 ifeq ($(CONFIG_XIP_KERNEL),y)
 
 $(obj)/xipImage: vmlinux FORCE
@@ -56,6 +64,10 @@ $(obj)/zImage:	$(obj)/compressed/vmlinux FORCE
 	$(call if_changed,objcopy)
 	@$(kecho) '  Kernel: $@ is ready'
 
+$(obj)/zImage-dtb:	$(obj)/zImage $(DTB_OBJS) FORCE
+	$(call if_changed,cat)
+	@echo '  Kernel: $@ is ready'
+
 endif
 
 ifneq ($(LOADADDR),)

arch/arm/boot/dts/Makefile

@@ -782,5 +782,15 @@ endif
 dtstree		:= $(srctree)/$(src)
 dtb-$(CONFIG_OF_ALL_DTBS) := $(patsubst $(dtstree)/%.dts,%.dtb, $(wildcard $(dtstree)/*.dts))
 
-always		:= $(dtb-y)
+DTB_NAMES := $(subst $\",,$(CONFIG_BUILD_ARM_APPENDED_DTB_IMAGE_NAMES))
+ifneq ($(DTB_NAMES),)
+DTB_LIST := $(addsuffix .dtb,$(DTB_NAMES))
+else
+DTB_LIST := $(dtb-y)
+endif
+
+targets += dtbs dtbs_install
+targets += $(DTB_LIST)
+
+always		:= $(DTB_LIST)
 clean-files	:= *.dtb

scripts/Makefile.lib

@@ -294,6 +294,12 @@ $(obj)/%.dtb: $(src)/%.dts FORCE
 
 dtc-tmp = $(subst $(comma),_,$(dot-target).dts.tmp)
 
+# cat
+# ---------------------------------------------------------------------------
+# Concatentate multiple files together
+quiet_cmd_cat = CAT     $@
+cmd_cat = (cat $(filter-out FORCE,$^) > $@) || (rm -f $@; false)
+
 # Bzip2
 # ---------------------------------------------------------------------------