Makefiles: Rename top-level Makefiles from .inc to .mk

The .inc suffix is confusing to various tools as it's not specific to
Makefiles. This means that editors don't recognize the files, and don't
open them with highlighting and any other specific editor functionality.

This issue is also seen in the release notes generation script where
Makefiles get renamed before running cloc.

The rest of the Makefiles will be renamed in following commits.

Signed-off-by: Martin Roth <gaumless@gmail.com>
Change-Id: Idaf69c6871d0bc1ee5e2e53157b8631c55eb3db9
Reviewed-on: https://review.coreboot.org/c/coreboot/+/80063
Reviewed-by: Felix Singer <service+coreboot-gerrit@felixsinger.de>
Reviewed-by: Maximilian Brune <maximilian.brune@9elements.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Nico Huber <nico.h@gmx.de>
diff --git a/Makefile b/Makefile
index b521f04..4a87d2f 100644
--- a/Makefile
+++ b/Makefile
@@ -50,7 +50,7 @@
 SYMLINK_LIST = $(call rwildcard,site-local/,symlink.txt)
 
 
-# directory containing the toplevel Makefile.inc
+# Directory containing the toplevel Makefile.mk
 TOPLEVEL := .
 
 CONFIG_SHELL := sh
@@ -102,7 +102,7 @@
 
 # This include must come _before_ the pattern rules below!
 # Order _does_ matter for pattern rules.
-include $(srck)/Makefile.inc
+include $(srck)/Makefile.mk
 
 # The cases where we don't need fully populated $(obj) lists:
 # 1. when no .config exists
@@ -153,11 +153,12 @@
 HOSTCC ?= $(if $(shell type gcc 2>/dev/null),gcc,cc)
 HOSTCXX ?= g++
 
-include $(TOPLEVEL)/Makefile.inc
-include $(TOPLEVEL)/payloads/Makefile.inc
-include $(TOPLEVEL)/util/testing/Makefile.inc
+include $(TOPLEVEL)/Makefile.mk
+include $(TOPLEVEL)/payloads/Makefile.mk
+include $(TOPLEVEL)/util/testing/Makefile.mk
+-include $(TOPLEVEL)/site-local/Makefile.mk
 -include $(TOPLEVEL)/site-local/Makefile.inc
-include $(TOPLEVEL)/tests/Makefile.inc
+include $(TOPLEVEL)/tests/Makefile.mk
 printall real-all:
 	@echo "Error: Trying to build, but NOCOMPILE is set." >&2
 	@echo "  Please file a bug with the following information:"
@@ -198,7 +199,7 @@
 export LANG LC_ALL TZ SOURCE_DATE_EPOCH
 
 ifneq ($(UNIT_TEST),1)
-include toolchain.inc
+include toolchain.mk
 endif
 
 strip_quotes = $(strip $(subst ",,$(subst \",,$(1))))
@@ -276,7 +277,7 @@
 	$(subst .$(1),,\
 	$(filter %.ads %.adb,$(2)))))))))
 
-# Clean -y variables, include Makefile.inc
+# Clean -y variables, include Makefile.mk & Makefile.inc
 # Add paths to files in X-y to X-srcs
 # Add subdirs-y to subdirs
 includemakefiles= \
@@ -295,10 +296,13 @@
 
 # For each path in $(subdirs) call includemakefiles
 # Repeat until subdirs is empty
+# TODO: Remove Makefile.inc support
 evaluate_subdirs= \
 	$(eval cursubdirs:=$(subdirs)) \
 	$(eval subdirs:=) \
 	$(foreach dir,$(cursubdirs), \
+		$(eval $(call includemakefiles,$(dir)/Makefile.mk))) \
+	$(foreach dir,$(cursubdirs), \
 		$(eval $(call includemakefiles,$(dir)/Makefile.inc))) \
 	$(if $(subdirs),$(eval $(call evaluate_subdirs)))
 
@@ -306,11 +310,11 @@
 subdirs:=$(TOPLEVEL)
 postinclude-hooks :=
 
-# Don't iterate through Makefile.incs under src/ when building tests
+# Don't iterate through Makefiles under src/ when building tests
 ifneq ($(UNIT_TEST),1)
 $(eval $(call evaluate_subdirs))
 else
-include $(TOPLEVEL)/tests/Makefile.inc
+include $(TOPLEVEL)/tests/Makefile.mk
 endif
 
 ifeq ($(FAILBUILD),1)
diff --git a/Makefile.inc b/Makefile.mk
similarity index 99%
rename from Makefile.inc
rename to Makefile.mk
index 23f56a4..87c6bcb 100644
--- a/Makefile.inc
+++ b/Makefile.mk
@@ -1158,7 +1158,7 @@
 
 endif # ifeq ($(CONFIG_ARCH_X86),y)
 
-$(obj)/fmap.fmd: $(top)/Makefile.inc $(DEFAULT_FLASHMAP) $(obj)/config.h
+$(obj)/fmap.fmd: $(top)/Makefile.mk $(DEFAULT_FLASHMAP) $(obj)/config.h
 	sed -e "s,##ROM_BASE##,$(FMAP_ROM_ADDR)," \
 	    -e "s,##ROM_SIZE##,$(FMAP_ROM_SIZE)," \
 	    -e "s,##BIOS_BASE##,$(FMAP_BIOS_BASE)," \
diff --git a/payloads/Makefile.inc b/payloads/Makefile.mk
similarity index 100%
rename from payloads/Makefile.inc
rename to payloads/Makefile.mk
diff --git a/payloads/coreinfo/Makefile b/payloads/coreinfo/Makefile
index 096e9c6..9655e24 100644
--- a/payloads/coreinfo/Makefile
+++ b/payloads/coreinfo/Makefile
@@ -70,7 +70,7 @@
 
 $(shell mkdir -p $(objk)/lxdialog $(KCONFIG_SPLITCONFIG))
 
-include $(srck)/Makefile.inc
+include $(srck)/Makefile.mk
 
 .PHONY: $(PHONY) prepare all real-all defaultbuild
 
diff --git a/payloads/libpayload/Makefile b/payloads/libpayload/Makefile
index 0104a11..212e67e 100644
--- a/payloads/libpayload/Makefile
+++ b/payloads/libpayload/Makefile
@@ -103,7 +103,7 @@
 
 # This include must come _before_ the pattern rules below!
 # Order _does_ matter for pattern rules.
-include $(srck)/Makefile.inc
+include $(srck)/Makefile.mk
 
 include $(HAVE_DOTCONFIG)
 
@@ -127,7 +127,7 @@
 # 3. when make distclean is run
 # 4. when make help% or make clean% is run
 # 5. when make %-test or make %-tests or make %coverage-report is run
-# Don't waste time on reading all Makefile.incs in these cases
+# Don't waste time on reading all Makefiles in these cases
 ifeq ($(strip $(HAVE_DOTCONFIG)),)
 NOCOMPILE := 1
 endif
diff --git a/tests/Makefile.inc b/tests/Makefile.mk
similarity index 100%
rename from tests/Makefile.inc
rename to tests/Makefile.mk
diff --git a/toolchain.inc b/toolchain.mk
similarity index 100%
rename from toolchain.inc
rename to toolchain.mk
diff --git a/util/kconfig/Makefile.inc b/util/kconfig/Makefile.mk
similarity index 100%
rename from util/kconfig/Makefile.inc
rename to util/kconfig/Makefile.mk
diff --git a/util/lint/kconfig_lint b/util/lint/kconfig_lint
index e67aebd..e64cf11 100755
--- a/util/lint/kconfig_lint
+++ b/util/lint/kconfig_lint
@@ -36,7 +36,7 @@
   '^build/\|^coreboot-builds/\|^configs/\|^util/\|^\.git/\|^payloads\|^Documentation\|^3rdparty'
   . '\|' .                            # directories to exclude when searching for used symbols
   '\.config\|\.txt$\|\.tex$\|\.tags\|/kconfig.h\|\.fmd'; #files to exclude when looking for symbols
-my $payload_files_to_check='payloads/Makefile.inc payloads/external/Makefile.inc';
+my $payload_files_to_check='payloads/Makefile.mk payloads/external/Makefile.inc';
 my $config_file = "";                 # name of config file to load symbol values from.
 my @wholeconfig;                      # document the entire kconfig structure
 my %loaded_files;                     # list of each Kconfig file loaded
diff --git a/util/testing/Makefile.inc b/util/testing/Makefile.mk
similarity index 100%
rename from util/testing/Makefile.inc
rename to util/testing/Makefile.mk