util/kconfig: Uprev to Linux 5.13's kconfig

This was originally several commits that had to be squashed into one
because the intermediate states weren't able to build coreboot:

 - one to remove everything that wasn't our own code, leaving only
   regex.[ch], toada.c, description.md and Makefile.inc.
 - one to copy in Linux 5.13's scripts/kconfig and adapt Makefile.inc
   to make the original Makefile work again.
 - adapt abuild to use olddefconfig, simplifying matters.
 - apply patches in util/kconfig/patches.
 - Some more adaptations to the libpayload build system.

The patches are now in util/kconfig/patches/, reverse applying them
should lead to a util/kconfig/ tree that contains exactly the Linux
version + our own 5 files.

Change-Id: Ia0e8fe4e9022b278f34ab113a433ef4d45e5c355
Signed-off-by: Patrick Georgi <pgeorgi@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/37152
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Raul Rangel <rrangel@chromium.org>

1 files changed, 62 insertions, 5 deletions

diff --git a/util/kconfig/Makefile.inc b/util/kconfig/Makefile.inc
index 27681f75a1..db8b1be1d3 100644
--- a/util/kconfig/Makefile.inc
+++ b/util/kconfig/Makefile.inc
@@ -1,12 +1,69 @@
 # SPDX-License-Identifier: GPL-2.0-or-later
 
-# Early configuration of coreboot specific changes
-Kconfig ?= src/Kconfig
+# Early coreboot specific configuration
+KBUILD_KCONFIG ?= src/Kconfig
 
-# Include verbatim Makefile
-include $(dir $(lastword $(MAKEFILE_LIST)))Makefile
+export LC_ALL=C
+export LANG=C
 
-# Extend Linux kconfig build rules
+# Include original Makefile, with just enough edits to work for us
+$(objk)/Makefile.real: $(dir $(lastword $(MAKEFILE_LIST)))Makefile
+	mkdir -p $(objk)
+	sed \
+		-e "s,\$$(obj),\$$(objk),g" \
+		-e "s,\$$(src),\$$(srck),g" \
+		-e "s,^help:,help_kconfig help::," \
+		-e "s,^%.config:,__disable__&," \
+		-e "s,^savedefconfig:,__disable__&," \
+		-e "s,\$$(srctree)/arch/\$$(SRCARCH)/configs/\$$(KBUILD_DEFCONFIG),\$$(KBUILD_DEFCONFIG)," \
+		-e "s,--defconfig=arch/\$$(SRCARCH)/configs/\$$(KBUILD_DEFCONFIG),--defconfig=\$$(KBUILD_DEFCONFIG)," \
+		-e "/^unexport CONFIG_$$/d" \
+		$< > $@.tmp
+	mv $@.tmp $@
+
+kecho := echo
+
+-include $(objk)/Makefile.real
+
+# Fill in Linux kconfig build rules to work
+
+oldconfig: KCONFIG_STRICT=
+
+savedefconfig: $(objk)/conf
+	cp $(DOTCONFIG) $(DEFCONFIG)
+	$< --savedefconfig=$(DEFCONFIG) $(KBUILD_KCONFIG)
+
+FORCE:
+
+filechk=$< > $@
+
+$(objk)/%.o: $(srck)/%.c
+	$(HOSTCC) -I $(srck) -I $(objk) -c $(HOSTCFLAGS_$(notdir $@)) -o $@ $<
+
+$(objk)/%.o: $(srck)/%.cc
+	$(HOSTCXX) -I $(srck) -I $(objk) -c $(HOSTCXXFLAGS_$(notdir $@)) -o $@ $<
+
+$(objk)/%.o: $(objk)/%.c
+	$(HOSTCC) -I $(srck) -I $(objk) -c -o $@ $<
+
+$(objk)/%.moc: $(srck)/%.h | $(objk)/qconf-cfg
+	$(call cmd_moc)
+
+define hostprogs_template
+# $1 entry in hostprogs
+$(objk)/$(1): $$(foreach _o,$$($(1)-objs) $$($(1)-cxxobjs),$(objk)/$$(_o)) | $(wildcard $(objk)/$(1)-cfg)
+	$$(HOSTCXX) -o $$@ $$^ $$(HOSTLDLIBS_$(1))
+endef
+
+$(foreach prog,$(hostprogs),$(eval $(call hostprogs_template,$(prog))))
+
+$(objk)/parser.tab.h: | $(objk)/parser.tab.c
+$(objk)/%.tab.h: | $(objk)/%.tab.c
+$(objk)/%.tab.c: $(srck)/%.y
+	bison -t -l --defines=$(objk)/$*.tab.h -b $(objk)/$* $<
+
+$(objk)/%.lex.c: $(srck)/%.l
+	flex -L -o$@ $<
 
 # Support mingw by shipping our own regex implementation
 _OS=$(shell uname -s |cut -c-7)