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/$(datafile_y)"
13
14# clean rules do not have CONFIG_INITRAMFS_COMPRESSION.  So clean up after all
15# possible compression formats.
16clean-files += initramfs_data.cpio*
17
18# Generate builtin.o based on initramfs_data.o
19obj-$(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
29hostprogs-y := gen_init_cpio
30initramfs   := $(CONFIG_SHELL) $(srctree)/$(src)/gen_initramfs_list.sh
31ramfs-input := $(if $(filter-out "",$(CONFIG_INITRAMFS_SOURCE)), \
32			$(shell echo $(CONFIG_INITRAMFS_SOURCE)),-d)
33ramfs-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# $(datafile_d_y) is used to identify all files included
38# in initramfs and to detect if any files are added/removed.
39# Removed files are identified by directory timestamp being updated
40# The dependency list is generated by gen_initramfs.sh -l
41ifneq ($(wildcard $(obj)/$(datafile_d_y)),)
42	include $(obj)/$(datafile_d_y)
43endif
44
45quiet_cmd_initfs = GEN     $@
46      cmd_initfs = $(initramfs) -o $@ $(ramfs-args) $(ramfs-input)
47
48targets := $(datafile_y)
49
50# do not try to update files included in initramfs
51$(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)
62