#
  # kbuild file for usr/ - including initramfs image
  #

  klibcdirs:;

  PHONY += klibcdirs

  # Gzip

  suffix_$(CONFIG_INITRAMFS_COMPRESSION_GZIP)   = .gz

  
  # Bzip2

  suffix_$(CONFIG_INITRAMFS_COMPRESSION_BZIP2)  = .bz2

  # Lzma
  suffix_$(CONFIG_INITRAMFS_COMPRESSION_LZMA)   = .lzma

  # XZ
  suffix_$(CONFIG_INITRAMFS_COMPRESSION_XZ)     = .xz

  # Lzo
  suffix_$(CONFIG_INITRAMFS_COMPRESSION_LZO)   = .lzo

  AFLAGS_initramfs_data.o += -DINITRAMFS_IMAGE="usr/initramfs_data.cpio$(suffix_y)"

  # Generate builtin.o based on initramfs_data.o

  obj-$(CONFIG_BLK_DEV_INITRD) := initramfs_data.o

  # initramfs_data.o contains the compressed initramfs_data.cpio image.

  # The image is included using .incbin, a dependency which is not
  # tracked automatically.

  $(obj)/initramfs_data.o: $(obj)/initramfs_data.cpio$(suffix_y) FORCE

  #####
  # Generate the initramfs cpio archive
  
  hostprogs-y := gen_init_cpio
  initramfs   := $(CONFIG_SHELL) $(srctree)/scripts/gen_initramfs_list.sh
  ramfs-input := $(if $(filter-out "",$(CONFIG_INITRAMFS_SOURCE)), \

  			$(shell echo $(CONFIG_INITRAMFS_SOURCE)),-d)

  ramfs-args  := \
          $(if $(CONFIG_INITRAMFS_ROOT_UID), -u $(CONFIG_INITRAMFS_ROOT_UID)) \

          $(if $(CONFIG_INITRAMFS_ROOT_GID), -g $(CONFIG_INITRAMFS_ROOT_GID))

  # .initramfs_data.cpio.d is used to identify all files included

  # in initramfs and to detect if any files are added/removed.
  # Removed files are identified by directory timestamp being updated
  # The dependency list is generated by gen_initramfs.sh -l

  ifneq ($(wildcard $(obj)/.initramfs_data.cpio.d),)
  	include $(obj)/.initramfs_data.cpio.d

  endif

  quiet_cmd_initfs = GEN     $@
        cmd_initfs = $(initramfs) -o $@ $(ramfs-args) $(ramfs-input)

  targets := initramfs_data.cpio.gz initramfs_data.cpio.bz2 initramfs_data.cpio.lzma initramfs_data.cpio.xz initramfs_data.cpio.lzo initramfs_data.cpio

  # do not try to update files included in initramfs
  $(deps_initramfs): ;

  $(deps_initramfs): klibcdirs

  # We rebuild initramfs_data.cpio if:
  # 1) Any included file is newer then initramfs_data.cpio

  # 2) There are changes in which files are included (added or deleted)

  # 3) If gen_init_cpio are newer than initramfs_data.cpio

  # 4) arguments to gen_initramfs.sh changes

  $(obj)/initramfs_data.cpio$(suffix_y): $(obj)/gen_init_cpio $(deps_initramfs) klibcdirs
  	$(Q)$(initramfs) -l $(ramfs-input) > $(obj)/.initramfs_data.cpio.d

  	$(call if_changed,initfs)