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>

6 files changed, 50 insertions, 1 deletions

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index a9c4e48..a63c3f5 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1863,6 +1863,21 @@ config DEPRECATED_PARAM_STRUCT
 	  This was deprecated in 2001 and announced to live on for 5 years.
 	  Some old boot loaders still use this way.
 
+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 list of
+	  DTBs to be built by default (instead of a standalone zImage.)
+	  The image will built in arch/arm/boot/zImage-dtb
+
+config BUILD_ARM_APPENDED_DTB_IMAGE_NAMES
+	string "Default dtb names"
+	depends on BUILD_ARM_APPENDED_DTB_IMAGE
+	help
+	  Space separated list of names of dtbs to append when
+	  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.
 config ZBOOT_ROM_TEXT
diff --git a/arch/arm/Makefile b/arch/arm/Makefile
index 61f6ccc..eb564e2 100644
--- a/arch/arm/Makefile
+++ b/arch/arm/Makefile
@@ -299,6 +299,8 @@ libs-y				:= arch/arm/lib/ $(libs-y)
 # Default target when executing plain make
 ifeq ($(CONFIG_XIP_KERNEL),y)
 KBUILD_IMAGE := xipImage
+else ifeq ($(CONFIG_BUILD_ARM_APPENDED_DTB_IMAGE),y)
+KBUILD_IMAGE := zImage-dtb
 else
 KBUILD_IMAGE := zImage
 endif
@@ -350,6 +352,9 @@ ifeq ($(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)
diff --git a/arch/arm/boot/.gitignore b/arch/arm/boot/.gitignore
index 3c79f85..ad7a025 100644
--- a/arch/arm/boot/.gitignore
+++ b/arch/arm/boot/.gitignore
@@ -4,3 +4,4 @@ xipImage
 bootpImage
 uImage
 *.dtb
+zImage-dtb
\ No newline at end of file
diff --git a/arch/arm/boot/Makefile b/arch/arm/boot/Makefile
index bdc1d5a..9ad4569 100644
--- a/arch/arm/boot/Makefile
+++ b/arch/arm/boot/Makefile
@@ -27,6 +27,14 @@ 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
@@ -53,6 +61,10 @@ $(obj)/compressed/vmlinux: $(obj)/Image FORCE
 $(obj)/zImage:	$(obj)/compressed/vmlinux FORCE
 	$(call if_changed,objcopy)
 
+$(obj)/zImage-dtb:	$(obj)/zImage $(DTB_OBJS) FORCE
+	$(call if_changed,cat)
+	@echo '  Kernel: $@ is ready'
+
 endif
 
 ifneq ($(LOADADDR),)
diff --git a/arch/arm/boot/dts/Makefile b/arch/arm/boot/dts/Makefile
index faacd52..d2f1b1d 100644
--- a/arch/arm/boot/dts/Makefile
+++ b/arch/arm/boot/dts/Makefile
@@ -924,5 +924,15 @@ 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
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 0a07f90..d3d3320 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -314,6 +314,12 @@ $(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
 # ---------------------------------------------------------------------------