@@ -267,6 +267,7 @@ xen/arch/*/efi/efi.h
xen/arch/*/efi/pe.c
xen/arch/*/efi/runtime.c
xen/arch/*/include/asm/asm-offsets.h
+xen/arch/*/include/generated
xen/build-dir-cppcheck/
xen/common/config_data.S
xen/common/config.gz
@@ -438,6 +438,7 @@ ifdef building_out_of_srctree
endif
CFLAGS += -I$(srctree)/include
CFLAGS += -I$(srctree)/arch/$(SRCARCH)/include
+CFLAGS += -I$(objtree)/arch/$(SRCARCH)/include/generated
# Note that link order matters!
ALL_OBJS-y := common/built_in.o
@@ -580,6 +581,7 @@ _clean:
rm -f $(TARGET).efi $(TARGET).efi.map $(TARGET).efi.elf $(TARGET).efi.stripped
rm -f asm-offsets.s arch/*/include/asm/asm-offsets.h
rm -f .banner .allconfig.tmp include/xen/compile.h
+ rm -rf $(objtree)/arch/*/include/generated
.PHONY: _distclean
_distclean: clean
@@ -589,7 +591,7 @@ $(TARGET).gz: $(TARGET)
gzip -n -f -9 < $< > $@.new
mv $@.new $@
-$(TARGET): outputmakefile FORCE
+$(TARGET): outputmakefile asm-generic FORCE
$(Q)$(MAKE) $(build)=tools
$(Q)$(MAKE) $(build)=. include/xen/compile.h
$(Q)$(MAKE) $(build)=include all
@@ -667,6 +669,12 @@ endif # need-sub-make
PHONY += FORCE
FORCE:
+# Support for using generic headers in asm-generic
+PHONY += asm-generic
+asm-generic:
+ $(Q)$(MAKE) -f $(srctree)/scripts/Makefile.asm-generic \
+ obj=arch/$(SRCARCH)/include/generated/asm
+
# Declare the contents of the PHONY variable as phony. We keep that
# information in a variable so we can use it in if_changed and friends.
.PHONY: $(PHONY)
new file mode 100644
@@ -0,0 +1,53 @@
+# SPDX-License-Identifier: GPL-2.0-only
+# include/asm-generic contains a lot of files that are used
+# verbatim by several architectures.
+#
+# This Makefile reads the file arch/$(SRCARCH)/include/asm/Makefile
+# and for each file listed in this file with generic-y creates
+# a small wrapper file in arch/$(SRCARCH)/include/generated/asm.
+
+PHONY := all
+all:
+
+src := $(subst /generated,,$(obj))
+
+include $(srctree)/scripts/Kbuild.include
+-include $(src)/Makefile
+
+redundant := $(filter $(mandatory-y) $(generated-y), $(generic-y))
+redundant += $(foreach f, $(generic-y), $(if $(wildcard $(srctree)/$(src)/$(f)),$(f)))
+redundant := $(sort $(redundant))
+$(if $(redundant),\
+ $(warning redundant generic-y found in $(src)/Kbuild: $(redundant)))
+
+# If arch does not implement mandatory headers, fallback to asm-generic ones.
+mandatory-y := $(filter-out $(generated-y), $(mandatory-y))
+generic-y += $(foreach f, $(mandatory-y), $(if $(wildcard $(srctree)/$(src)/$(f)),,$(f)))
+
+generic-y := $(addprefix $(obj)/, $(generic-y))
+generated-y := $(addprefix $(obj)/, $(generated-y))
+
+# Remove stale wrappers when the corresponding files are removed from generic-y
+old-headers := $(wildcard $(obj)/*.h)
+unwanted := $(filter-out $(generic-y) $(generated-y),$(old-headers))
+
+quiet_cmd_wrap = WRAP $@
+ cmd_wrap = echo "\#include <asm-generic/$*.h>" > $@
+
+quiet_cmd_remove = REMOVE $(unwanted)
+ cmd_remove = rm -f $(unwanted)
+
+all: $(generic-y)
+ $(if $(unwanted),$(call cmd,remove))
+ @:
+
+$(obj)/%.h:
+ $(call cmd,wrap)
+
+# Create output directory. Skip it if at least one old header exists
+# since we know the output directory already exists.
+ifeq ($(old-headers),)
+$(shell mkdir -p $(obj))
+endif
+
+.PHONY: $(PHONY)
Some headers are shared between individual architectures or are empty. To avoid duplication of these headers, asm-generic is introduced. With the following patch, an architecture uses generic headers mentioned in the file arch/$(ARCH)/include/asm/Makefile To use a generic header is needed to add to arch/$(ARCH)/include/asm/Makefile : generic-y += <name-of-header-file.h> For each mentioned header in arch/$(ARCH)/include/asm/Makefile, the necessary wrapper in arch/$(ARCH)/include/generated/asm will be generated. As the base Makefile.asm-generic from Linux kernel was taken. ( 06c2afb862f9da8 "Linux 6.5-rc1" ). Signed-off-by: Oleksii Kurochko <oleksii.kurochko@gmail.com> --- Changes in V5: - Update the commit message - Update SPDX license in Makefile. - Remove code related to UML - Include $(src)/Makefile instead of $(kbuild-file) - Update comment message in Makefile.asm-generic - Update .gitignore - Update path to generated headers in CFLAGS. - Use the latest version of Linux's Makefile.asm-generic --- Changes in V4: - introduce asm-generic support - update commit message --- Changes in V3: - Rename stubs dir to asm-generic --- Changes in V2: - Nothing changed. --- .gitignore | 1 + xen/Makefile | 10 +++++- xen/scripts/Makefile.asm-generic | 53 ++++++++++++++++++++++++++++++++ 3 files changed, 63 insertions(+), 1 deletion(-) create mode 100644 xen/scripts/Makefile.asm-generic