1 # ==========================================================================
3 # ==========================================================================
10 # Init all relevant variables used in kbuild files so
11 # 1) they have correct type
12 # 2) they do not inherit any value from the environment
33 # Read auto.conf if it exists, otherwise ignore
34 -include include/config/auto.conf
36 include scripts/Kbuild.include
38 # For backward compatibility check that these variables do not change
39 save-cflags := $(CFLAGS)
41 # The filename Kbuild has precedence over Makefile
42 kbuild-dir := $(if $(filter /%,$(src)),$(src),$(srctree)/$(src))
43 kbuild-file := $(if $(wildcard $(kbuild-dir)/Kbuild),$(kbuild-dir)/Kbuild,$(kbuild-dir)/Makefile)
44 include $(kbuild-file)
46 # If the save-* variables changed error out
47 ifeq ($(KBUILD_NOPEDANTIC),)
48 ifneq ("$(save-cflags)","$(CFLAGS)")
49 $(error CFLAGS was changed in "$(kbuild-file)". Fix it to use ccflags-y)
53 include scripts/Makefile.lib
56 ifneq ($(hostprogs-y),$(host-progs))
57 $(warning kbuild: $(obj)/Makefile - Usage of host-progs is deprecated. Please replace with hostprogs-y!)
58 hostprogs-y += $(host-progs)
62 # Do not include host rules unless needed
63 ifneq ($(hostprogs-y)$(hostprogs-m),)
64 include scripts/Makefile.host
67 ifneq ($(KBUILD_SRC),)
68 # Create output directory if not already present
69 _dummy := $(shell [ -d $(obj) ] || mkdir -p $(obj))
71 # Create directories for object files if directory does not exist
72 # Needed when obj-y := dir/file.o syntax is used
73 _dummy := $(foreach d,$(obj-dirs), $(shell [ -d $(d) ] || mkdir -p $(d)))
77 $(warning kbuild: Makefile.build is included improperly)
80 # ===========================================================================
82 ifneq ($(strip $(lib-y) $(lib-m) $(lib-)),)
83 lib-target := $(obj)/lib.a
86 ifneq ($(strip $(obj-y) $(obj-m) $(obj-) $(subdir-m) $(lib-target)),)
87 builtin-target := $(obj)/built-in.o
90 modorder-target := $(obj)/modules.order
92 # We keep a list of all modules in $(MODVERDIR)
94 __build: $(if $(KBUILD_BUILTIN),$(builtin-target) $(lib-target) $(extra-y)) \
95 $(if $(KBUILD_MODULES),$(obj-m) $(modorder-target)) \
96 $(subdir-ym) $(always)
99 # Linus' kernel sanity checking tool
100 ifneq ($(KBUILD_CHECKSRC),0)
101 ifeq ($(KBUILD_CHECKSRC),2)
102 quiet_cmd_force_checksrc = CHECK $<
103 cmd_force_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ;
105 quiet_cmd_checksrc = CHECK $<
106 cmd_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ;
110 # Do section mismatch analysis for each module/built-in.o
111 ifdef CONFIG_DEBUG_SECTION_MISMATCH
112 cmd_secanalysis = ; scripts/mod/modpost $@
115 # Compile C sources (.c)
116 # ---------------------------------------------------------------------------
118 # Default is built-in, unless we know otherwise
120 $(if $(part-of-module), \
121 $(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \
122 $(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL))
123 quiet_modtag := $(empty) $(empty)
125 $(real-objs-m) : part-of-module := y
126 $(real-objs-m:.o=.i) : part-of-module := y
127 $(real-objs-m:.o=.s) : part-of-module := y
128 $(real-objs-m:.o=.lst): part-of-module := y
130 $(real-objs-m) : quiet_modtag := [M]
131 $(real-objs-m:.o=.i) : quiet_modtag := [M]
132 $(real-objs-m:.o=.s) : quiet_modtag := [M]
133 $(real-objs-m:.o=.lst): quiet_modtag := [M]
135 $(obj-m) : quiet_modtag := [M]
137 # Default for not multi-part modules
138 modname = $(basetarget)
140 $(multi-objs-m) : modname = $(modname-multi)
141 $(multi-objs-m:.o=.i) : modname = $(modname-multi)
142 $(multi-objs-m:.o=.s) : modname = $(modname-multi)
143 $(multi-objs-m:.o=.lst) : modname = $(modname-multi)
144 $(multi-objs-y) : modname = $(modname-multi)
145 $(multi-objs-y:.o=.i) : modname = $(modname-multi)
146 $(multi-objs-y:.o=.s) : modname = $(modname-multi)
147 $(multi-objs-y:.o=.lst) : modname = $(modname-multi)
149 quiet_cmd_cc_s_c = CC $(quiet_modtag) $@
150 cmd_cc_s_c = $(CC) $(c_flags) $(DISABLE_LTO) -fverbose-asm -S -o $@ $<
152 $(obj)/%.s: $(src)/%.c FORCE
153 $(call if_changed_dep,cc_s_c)
155 quiet_cmd_cpp_i_c = CPP $(quiet_modtag) $@
156 cmd_cpp_i_c = $(CPP) $(c_flags) -o $@ $<
158 $(obj)/%.i: $(src)/%.c FORCE
159 $(call if_changed_dep,cpp_i_c)
162 $(CPP) -D__GENKSYMS__ $(c_flags) $< | \
163 $(GENKSYMS) $(if $(1), -T $(2)) \
164 $(patsubst y,-s _,$(CONFIG_HAVE_UNDERSCORE_SYMBOL_PREFIX)) \
165 $(if $(KBUILD_PRESERVE),-p) \
166 -r $(firstword $(wildcard $(2:.symtypes=.symref) /dev/null))
168 quiet_cmd_cc_symtypes_c = SYM $(quiet_modtag) $@
169 cmd_cc_symtypes_c = \
171 $(call cmd_gensymtypes,true,$@) >/dev/null; \
172 test -s $@ || rm -f $@
174 $(obj)/%.symtypes : $(src)/%.c FORCE
175 $(call cmd,cc_symtypes_c)
178 # The C file is compiled and updated dependency information is generated.
179 # (See cmd_cc_o_c + relevant part of rule_cc_o_c)
181 quiet_cmd_cc_o_c = CC $(quiet_modtag) $@
183 ifndef CONFIG_MODVERSIONS
184 cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
187 # When module versioning is enabled the following steps are executed:
188 # o compile a .tmp_<file>.o from <file>.c
189 # o if .tmp_<file>.o doesn't contain a __ksymtab version, i.e. does
190 # not export symbols, we just rename .tmp_<file>.o to <file>.o and
192 # o otherwise, we calculate symbol versions using the good old
193 # genksyms on the preprocessed source and postprocess them in a way
194 # that they are usable as a linker script
195 # o generate <file>.o from .tmp_<file>.o using the linker to
196 # replace the unresolved symbols __crc_exported_symbol with
197 # the actual value of the checksum generated by genksyms
199 cmd_cc_o_c = $(CC) $(c_flags) -c -o $(@D)/.tmp_$(@F) $<
201 if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then \
202 $(call cmd_gensymtypes,$(KBUILD_SYMTYPES),$(@:.o=.symtypes)) \
203 > $(@D)/.tmp_$(@F:.o=.ver); \
205 $(LD) $(LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F) \
206 -T $(@D)/.tmp_$(@F:.o=.ver); \
207 rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver); \
209 mv -f $(@D)/.tmp_$(@F) $@; \
213 ifdef CONFIG_FTRACE_MCOUNT_RECORD
214 ifdef BUILD_C_RECORDMCOUNT
215 ifeq ("$(origin RECORDMCOUNT_WARN)", "command line")
216 RECORDMCOUNT_FLAGS = -w
218 # Due to recursion, we must skip empty.o.
219 # The empty.o file is created in the make process in order to determine
220 # the target endianness and word size. It is made before all other C
221 # files, including recordmcount.
222 sub_cmd_record_mcount = \
223 if [ $(@) != "scripts/mod/empty.o" ]; then \
224 $(objtree)/scripts/recordmcount $(RECORDMCOUNT_FLAGS) "$(@)"; \
226 recordmcount_source := $(srctree)/scripts/recordmcount.c \
227 $(srctree)/scripts/recordmcount.h
229 sub_cmd_record_mcount = set -e ; perl $(srctree)/scripts/recordmcount.pl "$(ARCH)" \
230 "$(if $(CONFIG_CPU_BIG_ENDIAN),big,little)" \
231 "$(if $(CONFIG_64BIT),64,32)" \
232 "$(OBJDUMP)" "$(OBJCOPY)" "$(CC) $(KBUILD_CFLAGS)" \
233 "$(LD)" "$(NM)" "$(RM)" "$(MV)" \
234 "$(if $(part-of-module),1,0)" "$(@)";
235 recordmcount_source := $(srctree)/scripts/recordmcount.pl
237 cmd_record_mcount = \
238 if [ "$(findstring $(CC_FLAGS_FTRACE),$(_c_flags))" = \
239 "$(CC_FLAGS_FTRACE)" ]; then \
240 $(sub_cmd_record_mcount) \
244 ifdef CONFIG_STACK_VALIDATION
245 ifneq ($(SKIP_STACK_VALIDATION),1)
247 __objtool_obj := $(objtree)/tools/objtool/objtool
250 ifndef CONFIG_FRAME_POINTER
251 objtool_args += --no-fp
254 # 'OBJECT_FILES_NON_STANDARD := y': skip objtool checking for a directory
255 # 'OBJECT_FILES_NON_STANDARD_foo.o := 'y': skip objtool checking for a file
256 # 'OBJECT_FILES_NON_STANDARD_foo.o := 'n': override directory skip for a file
257 cmd_objtool = $(if $(patsubst y%,, \
258 $(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \
259 $(__objtool_obj) $(objtool_args) "$(@)";)
260 objtool_obj = $(if $(patsubst y%,, \
261 $(OBJECT_FILES_NON_STANDARD_$(basetarget).o)$(OBJECT_FILES_NON_STANDARD)n), \
264 endif # SKIP_STACK_VALIDATION
265 endif # CONFIG_STACK_VALIDATION
268 $(call echo-cmd,checksrc) $(cmd_checksrc) \
269 $(call cmd_and_fixdep,cc_o_c) \
272 $(call echo-cmd,record_mcount) $(cmd_record_mcount)
276 $(call cmd_and_fixdep,as_o_S) \
280 # List module undefined symbols (or empty line if not enabled)
281 ifdef CONFIG_TRIM_UNUSED_KSYMS
282 cmd_undef_syms = $(NM) $@ | sed -n 's/^ \+U //p' | xargs echo
284 cmd_undef_syms = echo
287 # Built-in and composite module parts
288 $(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_obj) FORCE
289 $(call cmd,force_checksrc)
290 $(call if_changed_rule,cc_o_c)
292 # Single-part modules are special since we need to mark them in $(MODVERDIR)
294 $(single-used-m): $(obj)/%.o: $(src)/%.c $(recordmcount_source) $(objtool_obj) FORCE
295 $(call cmd,force_checksrc)
296 $(call if_changed_rule,cc_o_c)
297 @{ echo $(@:.o=.ko); echo $@; \
298 $(cmd_undef_syms); } > $(MODVERDIR)/$(@F:.o=.mod)
300 quiet_cmd_cc_lst_c = MKLST $@
301 cmd_cc_lst_c = $(CC) $(c_flags) -g -c -o $*.o $< && \
302 $(CONFIG_SHELL) $(srctree)/scripts/makelst $*.o \
303 System.map $(OBJDUMP) > $@
305 $(obj)/%.lst: $(src)/%.c FORCE
306 $(call if_changed_dep,cc_lst_c)
308 # Compile assembler sources (.S)
309 # ---------------------------------------------------------------------------
311 modkern_aflags := $(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL)
313 $(real-objs-m) : modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
314 $(real-objs-m:.o=.s): modkern_aflags := $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE)
316 quiet_cmd_cpp_s_S = CPP $(quiet_modtag) $@
317 cmd_cpp_s_S = $(CPP) $(a_flags) -o $@ $<
319 $(obj)/%.s: $(src)/%.S FORCE
320 $(call if_changed_dep,cpp_s_S)
322 quiet_cmd_as_o_S = AS $(quiet_modtag) $@
323 cmd_as_o_S = $(CC) $(a_flags) -c -o $@ $<
325 $(obj)/%.o: $(src)/%.S $(objtool_obj) FORCE
326 $(call if_changed_rule,as_o_S)
328 targets += $(real-objs-y) $(real-objs-m) $(lib-y)
329 targets += $(extra-y) $(MAKECMDGOALS) $(always)
331 # Linker scripts preprocessor (.lds.S -> .lds)
332 # ---------------------------------------------------------------------------
333 quiet_cmd_cpp_lds_S = LDS $@
334 cmd_cpp_lds_S = $(CPP) $(cpp_flags) -P -C -U$(ARCH) \
335 -D__ASSEMBLY__ -DLINKER_SCRIPT -o $@ $<
337 $(obj)/%.lds: $(src)/%.lds.S FORCE
338 $(call if_changed_dep,cpp_lds_S)
341 # ---------------------------------------------------------------------------
342 quiet_cmd_asn1_compiler = ASN.1 $@
343 cmd_asn1_compiler = $(objtree)/scripts/asn1_compiler $< \
344 $(subst .h,.c,$@) $(subst .c,.h,$@)
346 .PRECIOUS: $(objtree)/$(obj)/%-asn1.c $(objtree)/$(obj)/%-asn1.h
348 $(obj)/%-asn1.c $(obj)/%-asn1.h: $(src)/%.asn1 $(objtree)/scripts/asn1_compiler
349 $(call cmd,asn1_compiler)
351 # Build the compiled-in targets
352 # ---------------------------------------------------------------------------
354 # To build objects in subdirs, we need to descend into the directories
355 $(sort $(subdir-obj-y)): $(subdir-ym) ;
358 # Rule to compile a set of .o files into one .o file
361 quiet_cmd_link_o_target = LD $@
362 # If the list of objects to link is empty, just create an empty built-in.o
363 cmd_link_o_target = $(if $(strip $(obj-y)),\
364 $(LD) $(ld_flags) -r -o $@ $(filter $(obj-y), $^) \
366 rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@)
368 $(builtin-target): $(obj-y) FORCE
369 $(call if_changed,link_o_target)
371 targets += $(builtin-target)
372 endif # builtin-target
375 # Rule to create modules.order file
377 # Create commands to either record .ko file or cat modules.order from
380 $(foreach m, $(modorder), \
381 $(if $(filter %/modules.order, $m), \
382 cat $m;, echo kernel/$m;))
384 $(modorder-target): $(subdir-ym) FORCE
385 $(Q)(cat /dev/null; $(modorder-cmds)) > $@
388 # Rule to compile a set of .o files into one .a file
391 quiet_cmd_link_l_target = AR $@
392 cmd_link_l_target = rm -f $@; $(AR) rcs$(KBUILD_ARFLAGS) $@ $(lib-y)
394 $(lib-target): $(lib-y) FORCE
395 $(call if_changed,link_l_target)
397 targets += $(lib-target)
401 # Rule to link composite objects
403 # Composite objects are specified in kbuild makefile as follows:
404 # <composite-object>-objs := <list of .o files>
406 # <composite-object>-y := <list of .o files>
408 # <composite-object>-m := <list of .o files>
409 # The -m syntax only works if <composite object> is a module
411 $(filter $(addprefix $(obj)/, \
412 $($(subst $(obj)/,,$(@:.o=-objs))) \
413 $($(subst $(obj)/,,$(@:.o=-y))) \
414 $($(subst $(obj)/,,$(@:.o=-m)))), $^)
416 quiet_cmd_link_multi-y = LD $@
417 cmd_link_multi-y = $(LD) $(ld_flags) -r -o $@ $(link_multi_deps) $(cmd_secanalysis)
419 quiet_cmd_link_multi-m = LD [M] $@
420 cmd_link_multi-m = $(cmd_link_multi-y)
422 $(multi-used-y): FORCE
423 $(call if_changed,link_multi-y)
424 $(call multi_depend, $(multi-used-y), .o, -objs -y)
426 $(multi-used-m): FORCE
427 $(call if_changed,link_multi-m)
428 @{ echo $(@:.o=.ko); echo $(link_multi_deps); \
429 $(cmd_undef_syms); } > $(MODVERDIR)/$(@F:.o=.mod)
430 $(call multi_depend, $(multi-used-m), .o, -objs -y -m)
432 targets += $(multi-used-y) $(multi-used-m)
436 # ---------------------------------------------------------------------------
438 PHONY += $(subdir-ym)
440 $(Q)$(MAKE) $(build)=$@
442 # Add FORCE to the prequisites of a target to force it to be always rebuilt.
443 # ---------------------------------------------------------------------------
449 # Read all saved command lines and dependencies for the $(targets) we
450 # may be building above, using $(if_changed{,_dep}). As an
451 # optimization, we don't need to read them if the target does not
452 # exist, we will rebuild anyway in that case.
454 targets := $(wildcard $(sort $(targets)))
455 cmd_files := $(wildcard $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
457 ifneq ($(cmd_files),)
461 # Declare the contents of the .PHONY variable as phony. We keep that
462 # information in a variable se we can use it in if_changed and friends.