usr/Makefile

   1 # SPDX-License-Identifier: GPL-2.0
   2 #
   3 # kbuild file for usr/ - including initramfs image
   4 #
   5
   6 klibcdirs:;
   7 PHONY += klibcdirs
   8
   9 suffix_y = $(subst $\",,$(CONFIG_INITRAMFS_COMPRESSION))
  10 datafile_y = initramfs_data.cpio$(suffix_y)
  11 AFLAGS_initramfs_data.o += -DINITRAMFS_IMAGE="usr/$(datafile_y)"
  12
  13
  14 # Generate builtin.o based on initramfs_data.o
  15 obj-$(CONFIG_BLK_DEV_INITRD) := initramfs_data.o
  16
  17 # initramfs_data.o contains the compressed initramfs_data.cpio image.
  18 # The image is included using .incbin, a dependency which is not
  19 # tracked automatically.
  20 $(obj)/initramfs_data.o: $(obj)/$(datafile_y) FORCE
  21
  22 #####
  23 # Generate the initramfs cpio archive
  24
  25 hostprogs-y := gen_init_cpio
  26 initramfs   := $(CONFIG_SHELL) $(srctree)/scripts/gen_initramfs_list.sh
  27 ramfs-input := $(if $(filter-out "",$(CONFIG_INITRAMFS_SOURCE)), \
  28                         $(shell echo $(CONFIG_INITRAMFS_SOURCE)),-d)
  29 ramfs-args  := \
  30         $(if $(CONFIG_INITRAMFS_ROOT_UID), -u $(CONFIG_INITRAMFS_ROOT_UID)) \
  31         $(if $(CONFIG_INITRAMFS_ROOT_GID), -g $(CONFIG_INITRAMFS_ROOT_GID))
  32
  33 # .initramfs_data.cpio.d is used to identify all files included
  34 # in initramfs and to detect if any files are added/removed.
  35 # Removed files are identified by directory timestamp being updated
  36 # The dependency list is generated by gen_initramfs.sh -l
  37 ifneq ($(wildcard $(obj)/.initramfs_data.cpio.d),)
  38         include $(obj)/.initramfs_data.cpio.d
  39 endif
  40
  41 quiet_cmd_initfs = GEN     $@
  42       cmd_initfs = $(initramfs) -o $@ $(ramfs-args) $(ramfs-input)
  43
  44 targets := $(datafile_y)
  45
  46 # do not try to update files included in initramfs
  47 $(deps_initramfs): ;
  48
  49 $(deps_initramfs): klibcdirs
  50 # We rebuild initramfs_data.cpio if:
  51 # 1) Any included file is newer then initramfs_data.cpio
  52 # 2) There are changes in which files are included (added or deleted)
  53 # 3) If gen_init_cpio are newer than initramfs_data.cpio
  54 # 4) arguments to gen_initramfs.sh changes
  55 $(obj)/$(datafile_y): $(obj)/gen_init_cpio $(deps_initramfs) klibcdirs
  56         $(Q)$(initramfs) -l $(ramfs-input) > $(obj)/.initramfs_data.cpio.d
  57         $(call if_changed,initfs)