1# SPDX-License-Identifier: GPL-2.0
2# Backward compatibility
3asflags-y  += $(EXTRA_AFLAGS)
4ccflags-y  += $(EXTRA_CFLAGS)
5cppflags-y += $(EXTRA_CPPFLAGS)
6ldflags-y  += $(EXTRA_LDFLAGS)
7
8# flags that take effect in current and sub directories
9KBUILD_AFLAGS += $(subdir-asflags-y)
10KBUILD_CFLAGS += $(subdir-ccflags-y)
11
12# Figure out what we need to build from the various variables
13# ===========================================================================
14
15# When an object is listed to be built compiled-in and modular,
16# only build the compiled-in version
17obj-m := $(filter-out $(obj-y),$(obj-m))
18
19# Libraries are always collected in one lib file.
20# Filter out objects already built-in
21lib-y := $(filter-out $(obj-y), $(sort $(lib-y) $(lib-m)))
22
23# Determine modorder.
24# Unfortunately, we don't have information about ordering between -y
25# and -m subdirs.  Just put -y's first.
26modorder	:= $(patsubst %/,%/modules.order, $(filter %/, $(obj-y)) $(obj-m:.o=.ko))
27
28# Handle objects in subdirs
29# ---------------------------------------------------------------------------
30# o if we encounter foo/ in $(obj-y), replace it by foo/built-in.a
31#   and add the directory to the list of dirs to descend into: $(subdir-y)
32# o if we encounter foo/ in $(obj-m), remove it from $(obj-m)
33#   and add the directory to the list of dirs to descend into: $(subdir-m)
34__subdir-y	:= $(patsubst %/,%,$(filter %/, $(obj-y)))
35subdir-y	+= $(__subdir-y)
36__subdir-m	:= $(patsubst %/,%,$(filter %/, $(obj-m)))
37subdir-m	+= $(__subdir-m)
38obj-y		:= $(patsubst %/, %/built-in.a, $(obj-y))
39obj-m		:= $(filter-out %/, $(obj-m))
40
41# Subdirectories we need to descend into
42subdir-ym	:= $(sort $(subdir-y) $(subdir-m))
43
44# If $(foo-objs), $(foo-y), $(foo-m), or $(foo-) exists, foo.o is a composite object
45multi-used-y := $(sort $(foreach m,$(obj-y), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-))), $(m))))
46multi-used-m := $(sort $(foreach m,$(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m)) $($(m:.o=-))), $(m))))
47multi-used   := $(multi-used-y) $(multi-used-m)
48
49# $(subdir-obj-y) is the list of objects in $(obj-y) which uses dir/ to
50# tell kbuild to descend
51subdir-obj-y := $(filter %/built-in.a, $(obj-y))
52
53# Replace multi-part objects by their individual parts,
54# including built-in.a from subdirectories
55real-obj-y := $(foreach m, $(obj-y), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-))),$($(m:.o=-objs)) $($(m:.o=-y)),$(m)))
56real-obj-m := $(foreach m, $(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m)) $($(m:.o=-))),$($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m)),$(m)))
57
58# DTB
59# If CONFIG_OF_ALL_DTBS is enabled, all DT blobs are built
60extra-y				+= $(dtb-y)
61extra-$(CONFIG_OF_ALL_DTBS)	+= $(dtb-)
62
63ifneq ($(CHECK_DTBS),)
64extra-y += $(patsubst %.dtb,%.dt.yaml, $(dtb-y))
65extra-$(CONFIG_OF_ALL_DTBS) += $(patsubst %.dtb,%.dt.yaml, $(dtb-))
66endif
67
68# Test self-contained headers
69
70# Wildcard searches in $(srctree)/$(src)/, but not in $(objtree)/$(obj)/.
71# Stale generated headers are often left over, so pattern matching should
72# be avoided. Please notice $(srctree)/$(src)/ and $(objtree)/$(obj) point
73# to the same location for in-tree building. So, header-test-pattern-y should
74# be used with care.
75header-test-y	+= $(filter-out $(header-test-), \
76		$(patsubst $(srctree)/$(src)/%, %, \
77		$(wildcard $(addprefix $(srctree)/$(src)/, \
78		$(header-test-pattern-y)))))
79
80extra-$(CONFIG_HEADER_TEST) += $(addsuffix .s, $(header-test-y) $(header-test-m))
81
82# Add subdir path
83
84extra-y		:= $(addprefix $(obj)/,$(extra-y))
85always		:= $(addprefix $(obj)/,$(always))
86targets		:= $(addprefix $(obj)/,$(targets))
87modorder	:= $(addprefix $(obj)/,$(modorder))
88obj-m		:= $(addprefix $(obj)/,$(obj-m))
89lib-y		:= $(addprefix $(obj)/,$(lib-y))
90subdir-obj-y	:= $(addprefix $(obj)/,$(subdir-obj-y))
91real-obj-y	:= $(addprefix $(obj)/,$(real-obj-y))
92real-obj-m	:= $(addprefix $(obj)/,$(real-obj-m))
93multi-used-m	:= $(addprefix $(obj)/,$(multi-used-m))
94subdir-ym	:= $(addprefix $(obj)/,$(subdir-ym))
95
96# Finds the multi-part object the current object will be linked into.
97# If the object belongs to two or more multi-part objects, all of them are
98# concatenated with a colon separator.
99modname-multi = $(subst $(space),:,$(sort $(foreach m,$(multi-used),\
100		$(if $(filter $*.o, $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m))),$(m:.o=)))))
101
102modname = $(if $(modname-multi),$(modname-multi),$(basetarget))
103
104# target with $(obj)/ and its suffix stripped
105target-stem = $(basename $(patsubst $(obj)/%,%,$@))
106
107# These flags are needed for modversions and compiling, so we define them here
108# $(modname_flags) defines KBUILD_MODNAME as the name of the module it will
109# end up in (or would, if it gets compiled in)
110name-fix = $(squote)$(quote)$(subst $(comma),_,$(subst -,_,$1))$(quote)$(squote)
111basename_flags = -DKBUILD_BASENAME=$(call name-fix,$(basetarget))
112modname_flags  = -DKBUILD_MODNAME=$(call name-fix,$(modname))
113
114orig_c_flags   = $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) \
115                 $(ccflags-y) $(CFLAGS_$(target-stem).o)
116_c_flags       = $(filter-out $(CFLAGS_REMOVE_$(target-stem).o), $(orig_c_flags))
117orig_a_flags   = $(KBUILD_CPPFLAGS) $(KBUILD_AFLAGS) \
118                 $(asflags-y) $(AFLAGS_$(target-stem).o)
119_a_flags       = $(filter-out $(AFLAGS_REMOVE_$(target-stem).o), $(orig_a_flags))
120_cpp_flags     = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$(target-stem).lds)
121
122#
123# Enable gcov profiling flags for a file, directory or for all files depending
124# on variables GCOV_PROFILE_obj.o, GCOV_PROFILE and CONFIG_GCOV_PROFILE_ALL
125# (in this order)
126#
127ifeq ($(CONFIG_GCOV_KERNEL),y)
128_c_flags += $(if $(patsubst n%,, \
129		$(GCOV_PROFILE_$(basetarget).o)$(GCOV_PROFILE)$(CONFIG_GCOV_PROFILE_ALL)), \
130		$(CFLAGS_GCOV))
131endif
132
133#
134# Enable address sanitizer flags for kernel except some files or directories
135# we don't want to check (depends on variables KASAN_SANITIZE_obj.o, KASAN_SANITIZE)
136#
137ifeq ($(CONFIG_KASAN),y)
138_c_flags += $(if $(patsubst n%,, \
139		$(KASAN_SANITIZE_$(basetarget).o)$(KASAN_SANITIZE)y), \
140		$(CFLAGS_KASAN), $(CFLAGS_KASAN_NOSANITIZE))
141endif
142
143ifeq ($(CONFIG_UBSAN),y)
144_c_flags += $(if $(patsubst n%,, \
145		$(UBSAN_SANITIZE_$(basetarget).o)$(UBSAN_SANITIZE)$(CONFIG_UBSAN_SANITIZE_ALL)), \
146		$(CFLAGS_UBSAN))
147endif
148
149ifeq ($(CONFIG_KCOV),y)
150_c_flags += $(if $(patsubst n%,, \
151	$(KCOV_INSTRUMENT_$(basetarget).o)$(KCOV_INSTRUMENT)$(CONFIG_KCOV_INSTRUMENT_ALL)), \
152	$(CFLAGS_KCOV))
153endif
154
155# $(srctree)/$(src) for including checkin headers from generated source files
156# $(objtree)/$(obj) for including generated headers from checkin source files
157ifeq ($(KBUILD_EXTMOD),)
158ifdef building_out_of_srctree
159_c_flags   += -I $(srctree)/$(src) -I $(objtree)/$(obj)
160_a_flags   += -I $(srctree)/$(src) -I $(objtree)/$(obj)
161_cpp_flags += -I $(srctree)/$(src) -I $(objtree)/$(obj)
162endif
163endif
164
165part-of-module = $(if $(filter $(basename $@).o, $(real-obj-m)),y)
166quiet_modtag = $(if $(part-of-module),[M],   )
167
168modkern_cflags =                                          \
169	$(if $(part-of-module),                           \
170		$(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \
171		$(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL))
172
173modkern_aflags = $(if $(part-of-module),				\
174			$(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE),	\
175			$(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL))
176
177c_flags        = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE)     \
178		 -include $(srctree)/include/linux/compiler_types.h       \
179		 $(_c_flags) $(modkern_cflags)                           \
180		 $(basename_flags) $(modname_flags)
181
182a_flags        = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE)     \
183		 $(_a_flags) $(modkern_aflags)
184
185cpp_flags      = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE)     \
186		 $(_cpp_flags)
187
188ld_flags       = $(KBUILD_LDFLAGS) $(ldflags-y) $(LDFLAGS_$(@F))
189
190DTC_INCLUDE    := $(srctree)/scripts/dtc/include-prefixes
191
192dtc_cpp_flags  = -Wp,-MD,$(depfile).pre.tmp -nostdinc                    \
193		 $(addprefix -I,$(DTC_INCLUDE))                          \
194		 -undef -D__DTS__
195
196# Useful for describing the dependency of composite objects
197# Usage:
198#   $(call multi_depend, multi_used_targets, suffix_to_remove, suffix_to_add)
199define multi_depend
200$(foreach m, $(notdir $1), \
201	$(eval $(obj)/$m: \
202	$(addprefix $(obj)/, $(foreach s, $3, $($(m:%$(strip $2)=%$(s)))))))
203endef
204
205# Shipped files
206# ===========================================================================
207
208quiet_cmd_shipped = SHIPPED $@
209cmd_shipped = cat $< > $@
210
211$(obj)/%: $(src)/%_shipped
212	$(call cmd,shipped)
213
214# Commands useful for building a boot image
215# ===========================================================================
216#
217#	Use as following:
218#
219#	target: source(s) FORCE
220#		$(if_changed,ld/objcopy/gzip)
221#
222#	and add target to extra-y so that we know we have to
223#	read in the saved command line
224
225# Linking
226# ---------------------------------------------------------------------------
227
228quiet_cmd_ld = LD      $@
229      cmd_ld = $(LD) $(ld_flags) $(real-prereqs) -o $@
230
231# Archive
232# ---------------------------------------------------------------------------
233
234quiet_cmd_ar = AR      $@
235      cmd_ar = rm -f $@; $(AR) cDPrsT $@ $(real-prereqs)
236
237# Objcopy
238# ---------------------------------------------------------------------------
239
240quiet_cmd_objcopy = OBJCOPY $@
241cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $(OBJCOPYFLAGS_$(@F)) $< $@
242
243# Gzip
244# ---------------------------------------------------------------------------
245
246quiet_cmd_gzip = GZIP    $@
247      cmd_gzip = cat $(real-prereqs) | gzip -n -f -9 > $@
248
249# DTC
250# ---------------------------------------------------------------------------
251DTC ?= $(objtree)/scripts/dtc/dtc
252
253# Disable noisy checks by default
254ifeq ($(findstring 1,$(KBUILD_EXTRA_WARN)),)
255DTC_FLAGS += -Wno-unit_address_vs_reg \
256	-Wno-unit_address_format \
257	-Wno-avoid_unnecessary_addr_size \
258	-Wno-alias_paths \
259	-Wno-graph_child_address \
260	-Wno-simple_bus_reg \
261	-Wno-unique_unit_address \
262	-Wno-pci_device_reg
263endif
264
265ifneq ($(findstring 2,$(KBUILD_EXTRA_WARN)),)
266DTC_FLAGS += -Wnode_name_chars_strict \
267	-Wproperty_name_chars_strict
268endif
269
270DTC_FLAGS += $(DTC_FLAGS_$(basetarget))
271
272# Generate an assembly file to wrap the output of the device tree compiler
273quiet_cmd_dt_S_dtb= DTB     $@
274cmd_dt_S_dtb=						\
275{							\
276	echo '\#include <asm-generic/vmlinux.lds.h>'; 	\
277	echo '.section .dtb.init.rodata,"a"';		\
278	echo '.balign STRUCT_ALIGNMENT';		\
279	echo '.global __dtb_$(subst -,_,$(*F))_begin';	\
280	echo '__dtb_$(subst -,_,$(*F))_begin:';		\
281	echo '.incbin "$<" ';				\
282	echo '__dtb_$(subst -,_,$(*F))_end:';		\
283	echo '.global __dtb_$(subst -,_,$(*F))_end';	\
284	echo '.balign STRUCT_ALIGNMENT'; 		\
285} > $@
286
287$(obj)/%.dtb.S: $(obj)/%.dtb FORCE
288	$(call if_changed,dt_S_dtb)
289
290quiet_cmd_dtc = DTC     $@
291cmd_dtc = mkdir -p $(dir ${dtc-tmp}) ; \
292	$(HOSTCC) -E $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $< ; \
293	$(DTC) -O $(2) -o $@ -b 0 \
294		$(addprefix -i,$(dir $<) $(DTC_INCLUDE)) $(DTC_FLAGS) \
295		-d $(depfile).dtc.tmp $(dtc-tmp) ; \
296	cat $(depfile).pre.tmp $(depfile).dtc.tmp > $(depfile)
297
298$(obj)/%.dtb: $(src)/%.dts $(DTC) FORCE
299	$(call if_changed_dep,dtc,dtb)
300
301DT_CHECKER ?= dt-validate
302DT_BINDING_DIR := Documentation/devicetree/bindings
303DT_TMP_SCHEMA := $(objtree)/$(DT_BINDING_DIR)/processed-schema.yaml
304
305quiet_cmd_dtb_check =	CHECK   $@
306      cmd_dtb_check =	$(DT_CHECKER) -u $(srctree)/$(DT_BINDING_DIR) -p $(DT_TMP_SCHEMA) $@ ;
307
308define rule_dtc_dt_yaml
309	$(call cmd_and_fixdep,dtc,yaml)
310	$(call cmd,dtb_check)
311endef
312
313$(obj)/%.dt.yaml: $(src)/%.dts $(DTC) $(DT_TMP_SCHEMA) FORCE
314	$(call if_changed_rule,dtc_dt_yaml)
315
316dtc-tmp = $(subst $(comma),_,$(dot-target).dts.tmp)
317
318# Bzip2
319# ---------------------------------------------------------------------------
320
321# Bzip2 and LZMA do not include size in file... so we have to fake that;
322# append the size as a 32-bit littleendian number as gzip does.
323size_append = printf $(shell						\
324dec_size=0;								\
325for F in $(real-prereqs); do					\
326	fsize=$$($(CONFIG_SHELL) $(srctree)/scripts/file-size.sh $$F);	\
327	dec_size=$$(expr $$dec_size + $$fsize);				\
328done;									\
329printf "%08x\n" $$dec_size |						\
330	sed 's/\(..\)/\1 /g' | {					\
331		read ch0 ch1 ch2 ch3;					\
332		for ch in $$ch3 $$ch2 $$ch1 $$ch0; do			\
333			printf '%s%03o' '\\' $$((0x$$ch)); 		\
334		done;							\
335	}								\
336)
337
338quiet_cmd_bzip2 = BZIP2   $@
339      cmd_bzip2 = { cat $(real-prereqs) | bzip2 -9; $(size_append); } > $@
340
341# Lzma
342# ---------------------------------------------------------------------------
343
344quiet_cmd_lzma = LZMA    $@
345      cmd_lzma = { cat $(real-prereqs) | lzma -9; $(size_append); } > $@
346
347quiet_cmd_lzo = LZO     $@
348      cmd_lzo = { cat $(real-prereqs) | lzop -9; $(size_append); } > $@
349
350quiet_cmd_lz4 = LZ4     $@
351      cmd_lz4 = { cat $(real-prereqs) | lz4c -l -c1 stdin stdout; \
352                  $(size_append); } > $@
353
354# U-Boot mkimage
355# ---------------------------------------------------------------------------
356
357MKIMAGE := $(srctree)/scripts/mkuboot.sh
358
359# SRCARCH just happens to match slightly more than ARCH (on sparc), so reduces
360# the number of overrides in arch makefiles
361UIMAGE_ARCH ?= $(SRCARCH)
362UIMAGE_COMPRESSION ?= $(if $(2),$(2),none)
363UIMAGE_OPTS-y ?=
364UIMAGE_TYPE ?= kernel
365UIMAGE_LOADADDR ?= arch_must_set_this
366UIMAGE_ENTRYADDR ?= $(UIMAGE_LOADADDR)
367UIMAGE_NAME ?= 'Linux-$(KERNELRELEASE)'
368
369quiet_cmd_uimage = UIMAGE  $@
370      cmd_uimage = $(BASH) $(MKIMAGE) -A $(UIMAGE_ARCH) -O linux \
371			-C $(UIMAGE_COMPRESSION) $(UIMAGE_OPTS-y) \
372			-T $(UIMAGE_TYPE) \
373			-a $(UIMAGE_LOADADDR) -e $(UIMAGE_ENTRYADDR) \
374			-n $(UIMAGE_NAME) -d $< $@
375
376# XZ
377# ---------------------------------------------------------------------------
378# Use xzkern to compress the kernel image and xzmisc to compress other things.
379#
380# xzkern uses a big LZMA2 dictionary since it doesn't increase memory usage
381# of the kernel decompressor. A BCJ filter is used if it is available for
382# the target architecture. xzkern also appends uncompressed size of the data
383# using size_append. The .xz format has the size information available at
384# the end of the file too, but it's in more complex format and it's good to
385# avoid changing the part of the boot code that reads the uncompressed size.
386# Note that the bytes added by size_append will make the xz tool think that
387# the file is corrupt. This is expected.
388#
389# xzmisc doesn't use size_append, so it can be used to create normal .xz
390# files. xzmisc uses smaller LZMA2 dictionary than xzkern, because a very
391# big dictionary would increase the memory usage too much in the multi-call
392# decompression mode. A BCJ filter isn't used either.
393quiet_cmd_xzkern = XZKERN  $@
394      cmd_xzkern = { cat $(real-prereqs) | sh $(srctree)/scripts/xz_wrap.sh; \
395                     $(size_append); } > $@
396
397quiet_cmd_xzmisc = XZMISC  $@
398      cmd_xzmisc = cat $(real-prereqs) | xz --check=crc32 --lzma2=dict=1MiB > $@
399
400# ASM offsets
401# ---------------------------------------------------------------------------
402
403# Default sed regexp - multiline due to syntax constraints
404#
405# Use [:space:] because LLVM's integrated assembler inserts <tab> around
406# the .ascii directive whereas GCC keeps the <space> as-is.
407define sed-offsets
408	's:^[[:space:]]*\.ascii[[:space:]]*"\(.*\)".*:\1:; \
409	/^->/{s:->#\(.*\):/* \1 */:; \
410	s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \
411	s:->::; p;}'
412endef
413
414# Use filechk to avoid rebuilds when a header changes, but the resulting file
415# does not
416define filechk_offsets
417	 echo "#ifndef $2"; \
418	 echo "#define $2"; \
419	 echo "/*"; \
420	 echo " * DO NOT MODIFY."; \
421	 echo " *"; \
422	 echo " * This file was generated by Kbuild"; \
423	 echo " */"; \
424	 echo ""; \
425	 sed -ne $(sed-offsets) < $<; \
426	 echo ""; \
427	 echo "#endif"
428endef
429