kbuild: split final module linking out into Makefile.modfinal

I think splitting the modpost and linking modules into separate
Makefiles will be useful especially when more complex build steps
come in. The main motivation of this commit is to integrate the
proposed klp-convert feature cleanly.

I moved the logging 'Building modules, stage 2.' to Makefile.modpost
to avoid the code duplication although I do not know whether or not
this message is needed in the first place.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

1 files changed, 60 insertions, 0 deletions

diff --git a/scripts/Makefile.modfinal b/scripts/Makefile.modfinal
new file mode 100644
index 000000000000..c8875f62dd96
--- /dev/null
+++ b/scripts/Makefile.modfinal
@@ -0,0 +1,60 @@
+# SPDX-License-Identifier: GPL-2.0-only
+# ===========================================================================
+# Module final link
+# ===========================================================================
+
+PHONY := __modfinal
+__modfinal:
+
+include $(srctree)/scripts/Kbuild.include
+
+# for c_flags
+include $(srctree)/scripts/Makefile.lib
+
+# find all modules listed in modules.order
+modules := $(sort $(shell cat $(MODORDER)))
+
+__modfinal: $(modules)
+	@:
+
+# modname is set to make c_flags define KBUILD_MODNAME
+modname = $(notdir $(@:.mod.o=))
+
+quiet_cmd_cc_o_c = CC [M]  $@
+      cmd_cc_o_c = $(CC) $(c_flags) $(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE) \
+		   -c -o $@ $<
+
+%.mod.o: %.mod.c FORCE
+	$(call if_changed_dep,cc_o_c)
+
+ARCH_POSTLINK := $(wildcard $(srctree)/arch/$(SRCARCH)/Makefile.postlink)
+
+quiet_cmd_ld_ko_o = LD [M]  $@
+      cmd_ld_ko_o =                                                     \
+	$(LD) -r $(KBUILD_LDFLAGS)					\
+		$(KBUILD_LDFLAGS_MODULE) $(LDFLAGS_MODULE)		\
+		$(addprefix -T , $(KBUILD_LDS_MODULE))			\
+		-o $@ $(filter %.o, $^);				\
+	$(if $(ARCH_POSTLINK), $(MAKE) -f $(ARCH_POSTLINK) $@, true)
+
+$(modules): %.ko: %.o %.mod.o $(KBUILD_LDS_MODULE) FORCE
+	+$(call if_changed,ld_ko_o)
+
+targets += $(modules) $(modules:.ko=.mod.o)
+
+# Add FORCE to the prequisites of a target to force it to be always rebuilt.
+# ---------------------------------------------------------------------------
+
+PHONY += FORCE
+FORCE:
+
+# Read all saved command lines and dependencies for the $(targets) we
+# may be building above, using $(if_changed{,_dep}). As an
+# optimization, we don't need to read them if the target does not
+# exist, we will rebuild anyway in that case.
+
+existing-targets := $(wildcard $(sort $(targets)))
+
+-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd)
+
+.PHONY: $(PHONY)