1# SPDX-License-Identifier: GPL-2.0 2# 3# kbuild file for usr/ - including initramfs image 4# 5 6compress-y := copy 7compress-$(CONFIG_INITRAMFS_COMPRESSION_GZIP) := gzip 8compress-$(CONFIG_INITRAMFS_COMPRESSION_BZIP2) := bzip2 9compress-$(CONFIG_INITRAMFS_COMPRESSION_LZMA) := lzma 10compress-$(CONFIG_INITRAMFS_COMPRESSION_XZ) := xzmisc 11compress-$(CONFIG_INITRAMFS_COMPRESSION_LZO) := lzo 12compress-$(CONFIG_INITRAMFS_COMPRESSION_LZ4) := lz4 13compress-$(CONFIG_INITRAMFS_COMPRESSION_ZSTD) := zstd 14 15obj-$(CONFIG_BLK_DEV_INITRD) := initramfs_data.o 16 17$(obj)/initramfs_data.o: $(obj)/initramfs_inc_data 18 19ramfs-input := $(CONFIG_INITRAMFS_SOURCE) 20cpio-data := 21 22# If CONFIG_INITRAMFS_SOURCE is empty, generate a small initramfs with the 23# default contents. 24ifeq ($(ramfs-input),) 25ramfs-input := $(srctree)/$(src)/default_cpio_list 26endif 27 28ifeq ($(words $(ramfs-input)),1) 29 30# If CONFIG_INITRAMFS_SOURCE specifies a single file, and it is suffixed with 31# .cpio, use it directly as an initramfs. 32ifneq ($(filter %.cpio,$(ramfs-input)),) 33cpio-data := $(ramfs-input) 34endif 35 36# If CONFIG_INITRAMFS_SOURCE specifies a single file, and it is suffixed with 37# .cpio.*, use it directly as an initramfs, and avoid double compression. 38ifeq ($(words $(subst .cpio.,$(space),$(ramfs-input))),2) 39cpio-data := $(ramfs-input) 40compress-y := copy 41endif 42 43endif 44 45# For other cases, generate the initramfs cpio archive based on the contents 46# specified by CONFIG_INITRAMFS_SOURCE. 47ifeq ($(cpio-data),) 48 49cpio-data := $(obj)/initramfs_data.cpio 50 51hostprogs := gen_init_cpio 52 53# .initramfs_data.cpio.d is used to identify all files included 54# in initramfs and to detect if any files are added/removed. 55# Removed files are identified by directory timestamp being updated 56# The dependency list is generated by gen_initramfs.sh -l 57-include $(obj)/.initramfs_data.cpio.d 58 59# do not try to update files included in initramfs 60$(deps_initramfs): ; 61 62quiet_cmd_initfs = GEN $@ 63 cmd_initfs = \ 64 $(CONFIG_SHELL) $< -o $@ -l $(obj)/.initramfs_data.cpio.d \ 65 $(if $(CONFIG_INITRAMFS_ROOT_UID), -u $(CONFIG_INITRAMFS_ROOT_UID)) \ 66 $(if $(CONFIG_INITRAMFS_ROOT_GID), -g $(CONFIG_INITRAMFS_ROOT_GID)) \ 67 $(ramfs-input) 68 69# We rebuild initramfs_data.cpio if: 70# 1) Any included file is newer than initramfs_data.cpio 71# 2) There are changes in which files are included (added or deleted) 72# 3) If gen_init_cpio are newer than initramfs_data.cpio 73# 4) Arguments to gen_initramfs.sh changes 74$(obj)/initramfs_data.cpio: $(src)/gen_initramfs.sh $(obj)/gen_init_cpio $(deps_initramfs) FORCE 75 $(call if_changed,initfs) 76 77endif 78 79$(obj)/initramfs_inc_data: $(cpio-data) FORCE 80 $(call if_changed,$(compress-y)) 81 82targets += initramfs_data.cpio initramfs_inc_data 83 84subdir-$(CONFIG_UAPI_HEADER_TEST) += include 85