xref: /linux/usr/Makefile (revision bd628c1bed7902ec1f24ba0fe70758949146abbe)
1# SPDX-License-Identifier: GPL-2.0
2#
3# kbuild file for usr/ - including initramfs image
4#
5
6klibcdirs:;
7PHONY += klibcdirs
8
9suffix_y = $(subst $\",,$(CONFIG_INITRAMFS_COMPRESSION))
10datafile_y = initramfs_data.cpio$(suffix_y)
11datafile_d_y = .$(datafile_y).d
12AFLAGS_initramfs_data.o += -DINITRAMFS_IMAGE="usr/$(datafile_y)"
13
14
15# Generate builtin.o based on initramfs_data.o
16obj-$(CONFIG_BLK_DEV_INITRD) := initramfs_data.o
17
18# initramfs_data.o contains the compressed initramfs_data.cpio image.
19# The image is included using .incbin, a dependency which is not
20# tracked automatically.
21$(obj)/initramfs_data.o: $(obj)/$(datafile_y) FORCE
22
23#####
24# Generate the initramfs cpio archive
25
26hostprogs-y := gen_init_cpio
27initramfs   := $(CONFIG_SHELL) $(srctree)/$(src)/gen_initramfs_list.sh
28ramfs-input := $(if $(filter-out "",$(CONFIG_INITRAMFS_SOURCE)), \
29			$(shell echo $(CONFIG_INITRAMFS_SOURCE)),-d)
30ramfs-args  := \
31        $(if $(CONFIG_INITRAMFS_ROOT_UID), -u $(CONFIG_INITRAMFS_ROOT_UID)) \
32        $(if $(CONFIG_INITRAMFS_ROOT_GID), -g $(CONFIG_INITRAMFS_ROOT_GID))
33
34# $(datafile_d_y) is used to identify all files included
35# in initramfs and to detect if any files are added/removed.
36# Removed files are identified by directory timestamp being updated
37# The dependency list is generated by gen_initramfs.sh -l
38ifneq ($(wildcard $(obj)/$(datafile_d_y)),)
39	include $(obj)/$(datafile_d_y)
40endif
41
42quiet_cmd_initfs = GEN     $@
43      cmd_initfs = $(initramfs) -o $@ $(ramfs-args) $(ramfs-input)
44
45targets := $(datafile_y)
46
47# do not try to update files included in initramfs
48$(deps_initramfs): ;
49
50$(deps_initramfs): klibcdirs
51# We rebuild initramfs_data.cpio if:
52# 1) Any included file is newer than initramfs_data.cpio
53# 2) There are changes in which files are included (added or deleted)
54# 3) If gen_init_cpio are newer than initramfs_data.cpio
55# 4) Arguments to gen_initramfs.sh changes
56$(obj)/$(datafile_y): $(obj)/gen_init_cpio $(deps_initramfs) klibcdirs
57	$(Q)$(initramfs) -l $(ramfs-input) > $(obj)/$(datafile_d_y)
58	$(call if_changed,initfs)
59