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$(suffix_y)
  11 datafile_d_y = .$(datafile_y).d
  12 AFLAGS_initramfs_data.o += -DINITRAMFS_IMAGE="usr/$(datafile_y)"
  13
  14 # clean rules do not have CONFIG_INITRAMFS_COMPRESSION.  So clean up after all
  15 # possible compression formats.
  16 clean-files += initramfs_data.cpio*
  17
  18 # Generate builtin.o based on initramfs_data.o
  19 obj-$(CONFIG_BLK_DEV_INITRD) := initramfs_data.o
  20
  21 # initramfs_data.o contains the compressed initramfs_data.cpio image.
  22 # The image is included using .incbin, a dependency which is not
  23 # tracked automatically.
  24 $(obj)/initramfs_data.o: $(obj)/$(datafile_y) FORCE
  25
  26 #####
  27 # Generate the initramfs cpio archive
  28
  29 hostprogs-y := gen_init_cpio
  30 initramfs   := $(CONFIG_SHELL) $(srctree)/scripts/gen_initramfs_list.sh
  31 ramfs-input := $(if $(filter-out "",$(CONFIG_INITRAMFS_SOURCE)), \
  32                         $(shell echo $(CONFIG_INITRAMFS_SOURCE)),-d)
  33 ramfs-args  := \
  34         $(if $(CONFIG_INITRAMFS_ROOT_UID), -u $(CONFIG_INITRAMFS_ROOT_UID)) \
  35         $(if $(CONFIG_INITRAMFS_ROOT_GID), -g $(CONFIG_INITRAMFS_ROOT_GID))
  36
  37 # $(datafile_d_y) is used to identify all files included
  38 # in initramfs and to detect if any files are added/removed.
  39 # Removed files are identified by directory timestamp being updated
  40 # The dependency list is generated by gen_initramfs.sh -l
  41 ifneq ($(wildcard $(obj)/$(datafile_d_y)),)
  42         include $(obj)/$(datafile_d_y)
  43 endif
  44
  45 quiet_cmd_initfs = GEN     $@
  46       cmd_initfs = $(initramfs) -o $@ $(ramfs-args) $(ramfs-input)
  47
  48 targets := $(datafile_y)
  49
  50 # do not try to update files included in initramfs
  51 $(deps_initramfs): ;
  52
  53 $(deps_initramfs): klibcdirs
  54 # We rebuild initramfs_data.cpio if:
  55 # 1) Any included file is newer then initramfs_data.cpio
  56 # 2) There are changes in which files are included (added or deleted)
  57 # 3) If gen_init_cpio are newer than initramfs_data.cpio
  58 # 4) arguments to gen_initramfs.sh changes
  59 $(obj)/$(datafile_y): $(obj)/gen_init_cpio $(deps_initramfs) klibcdirs
  60         $(Q)$(initramfs) -l $(ramfs-input) > $(obj)/$(datafile_d_y)
  61         $(call if_changed,initfs)