1 files changed, 75 insertions, 0 deletions
diff --git a/usr/Kbuild b/usr/Kbuild
new file mode 100644
index 0000000..890811c
--- /dev/null
+++ b/usr/Kbuild
@@ -0,0 +1,75 @@
+#
+# kbuild file for usr/ - including initramfs image and klibc
+#
+
+CONFIG_KLIBC := 1
+
+include-subdir := include
+klibc-subdir := klibc
+usr-subdirs  := kinit utils dash gzip
+subdir-      := $(include-subdir) $(klibc-subdir) $(usr-subdirs)
+
+usr-subdirs  := $(addprefix _usr_,$(usr-subdirs))
+klibc-subdir := $(addprefix _usr_,$(klibc-subdir))
+
+# klibc binaries
+ifdef CONFIG_KLIBC
+
+# .initramfs_data.cpio.gz.d is used to identify all files included
+# in initramfs and to detect if any files are added/removed.
+# Removed files are identified by directory timestamp being updated
+# The dependency list is generated by gen_initramfs.sh -l
+ifneq ($(wildcard $(obj)/.initramfs_data.cpio.gz.d),)
+	include $(obj)/.initramfs_data.cpio.gz.d
+endif
+
+# build klibc library before the klibc programs
+# build klibc programs before cpio.gz
+.PHONY: initramfs $(usr-subdirs) $(klibc-subdir) $(include-subdir)
+initramfs:         $(usr-subdirs) $(klibc-subdir) $(include-subdir)
+$(deps_initramfs): $(usr-subdirs) $(klibc-subdir) $(include-subdir)
+
+$(usr-subdirs): $(klibc-subdir)
+	$(Q)$(MAKE) $(klibc)=$(src)/$(patsubst _usr_%,%,$(@))
+
+$(klibc-subdir): $(include-subdir)
+	$(Q)$(MAKE) $(klibc)=$(src)/$(patsubst _usr_%,%,$(@))
+
+$(include-subdir):
+	$(Q)$(MAKE) $(klibc)=$(src)/$(patsubst _usr_%,%,$(@))
+endif
+
+
+# Generate builtin.o based on initramfs_data.o
+obj-y := initramfs_data.o
+
+# initramfs_data.o contains the initramfs_data.cpio.gz image.
+# The image is included using .incbin, a dependency which is not
+# tracked automatically.
+$(obj)/initramfs_data.o: $(obj)/initramfs_data.cpio.gz FORCE
+
+#####
+# Generate the initramfs cpio archive
+
+hostprogs-y := gen_init_cpio
+ginitramfs  := $(CONFIG_SHELL) $(srctree)/scripts/gen_initramfs_list.sh
+ramfs-def   := $(srctree)/$(src)/initramfs.default
+ramfs-input := $(shell echo $(CONFIG_INITRAMFS_SOURCE))
+ramfs-input := $(if $(ramfs-input), $(ramfs-input), $(ramfs-def))
+
+ramfs-args  := \
+        $(if $(CONFIG_INITRAMFS_ROOT_UID), -u $(CONFIG_INITRAMFS_ROOT_UID)) \
+        $(if $(CONFIG_INITRAMFS_ROOT_GID), -g $(CONFIG_INITRAMFS_ROOT_GID))
+
+quiet_cmd_initfs = GEN     $@
+      cmd_initfs = $(ginitramfs) -o $@ $(ramfs-args) $(ramfs-input)
+
+targets := initramfs_data.cpio.gz
+# We rebuild initramfs_data.cpio.gz if:
+# 1) Any included file is newer then initramfs_data.cpio.gz
+# 2) There are changes in which files are included (added or deleted)
+# 3) If gen_init_cpio are newer than initramfs_data.cpio.gz
+# 4) arguments to gen_initramfs.sh changes
+$(obj)/initramfs_data.cpio.gz: $(obj)/gen_init_cpio $(deps_initramfs) initramfs
+	$(Q)$(ginitramfs) -l $(ramfs-input) > $(obj)/.initramfs_data.cpio.gz.d
+	$(call if_changed,initfs)