scripts/Makefile.build

   1 # ==========================================================================
   2 # Building
   3 # ==========================================================================
   4
   5 src := $(obj)
   6
   7 PHONY := __build
   8 __build:
   9
  10 # Read .config if it exist, otherwise ignore
  11 -include include/config/auto.conf
  12
  13 include scripts/Kbuild.include
  14
  15 # The filename Kbuild has precedence over Makefile
  16 kbuild-dir := $(if $(filter /%,$(src)),$(src),$(srctree)/$(src))
  17 include $(if $(wildcard $(kbuild-dir)/Kbuild), $(kbuild-dir)/Kbuild, $(kbuild-dir)/Makefile)
  18
  19 include scripts/Makefile.lib
  20
  21 ifdef host-progs
  22 ifneq ($(hostprogs-y),$(host-progs))
  23 $(warning kbuild: $(obj)/Makefile - Usage of host-progs is deprecated. Please replace with hostprogs-y!)
  24 hostprogs-y += $(host-progs)
  25 endif
  26 endif
  27
  28 # Do not include host rules unles needed
  29 ifneq ($(hostprogs-y)$(hostprogs-m),)
  30 include scripts/Makefile.host
  31 endif
  32
  33 ifneq ($(KBUILD_SRC),)
  34 # Create output directory if not already present
  35 _dummy := $(shell [ -d $(obj) ] || mkdir -p $(obj))
  36
  37 # Create directories for object files if directory does not exist
  38 # Needed when obj-y := dir/file.o syntax is used
  39 _dummy := $(foreach d,$(obj-dirs), $(shell [ -d $(d) ] || mkdir -p $(d)))
  40 endif
  41
  42
  43 ifdef EXTRA_TARGETS
  44 $(warning kbuild: $(obj)/Makefile - Usage of EXTRA_TARGETS is obsolete in 2.6. Please fix!)
  45 endif
  46
  47 ifdef build-targets
  48 $(warning kbuild: $(obj)/Makefile - Usage of build-targets is obsolete in 2.6. Please fix!)
  49 endif
  50
  51 ifdef export-objs
  52 $(warning kbuild: $(obj)/Makefile - Usage of export-objs is obsolete in 2.6. Please fix!)
  53 endif
  54
  55 ifdef O_TARGET
  56 $(warning kbuild: $(obj)/Makefile - Usage of O_TARGET := $(O_TARGET) is obsolete in 2.6. Please fix!)
  57 endif
  58
  59 ifdef L_TARGET
  60 $(error kbuild: $(obj)/Makefile - Use of L_TARGET is replaced by lib-y in 2.6. Please fix!)
  61 endif
  62
  63 ifdef list-multi
  64 $(warning kbuild: $(obj)/Makefile - list-multi := $(list-multi) is obsolete in 2.6. Please fix!)
  65 endif
  66
  67 ifndef obj
  68 $(warning kbuild: Makefile.build is included improperly)
  69 endif
  70
  71 # ===========================================================================
  72
  73 ifneq ($(strip $(lib-y) $(lib-m) $(lib-n) $(lib-)),)
  74 lib-target := $(obj)/lib.a
  75 endif
  76
  77 ifneq ($(strip $(obj-y) $(obj-m) $(obj-n) $(obj-) $(lib-target)),)
  78 builtin-target := $(obj)/built-in.o
  79 endif
  80
  81 # We keep a list of all modules in $(MODVERDIR)
  82
  83 __build: $(if $(KBUILD_BUILTIN),$(builtin-target) $(lib-target) $(extra-y)) \
  84          $(if $(KBUILD_MODULES),$(obj-m)) \
  85          $(subdir-ym) $(always)
  86         @:
  87
  88 # Linus' kernel sanity checking tool
  89 ifneq ($(KBUILD_CHECKSRC),0)
  90   ifeq ($(KBUILD_CHECKSRC),2)
  91     quiet_cmd_force_checksrc = CHECK   $<
  92           cmd_force_checksrc = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ;
  93   else
  94       quiet_cmd_checksrc     = CHECK   $<
  95             cmd_checksrc     = $(CHECK) $(CHECKFLAGS) $(c_flags) $< ;
  96   endif
  97 endif
  98
  99
 100 # Compile C sources (.c)
 101 # ---------------------------------------------------------------------------
 102
 103 # Default is built-in, unless we know otherwise
 104 modkern_cflags := $(CFLAGS_KERNEL)
 105 quiet_modtag := $(empty)   $(empty)
 106
 107 $(real-objs-m)        : modkern_cflags := $(CFLAGS_MODULE)
 108 $(real-objs-m:.o=.i)  : modkern_cflags := $(CFLAGS_MODULE)
 109 $(real-objs-m:.o=.s)  : modkern_cflags := $(CFLAGS_MODULE)
 110 $(real-objs-m:.o=.lst): modkern_cflags := $(CFLAGS_MODULE)
 111
 112 $(real-objs-m)        : quiet_modtag := [M]
 113 $(real-objs-m:.o=.i)  : quiet_modtag := [M]
 114 $(real-objs-m:.o=.s)  : quiet_modtag := [M]
 115 $(real-objs-m:.o=.lst): quiet_modtag := [M]
 116
 117 $(obj-m)              : quiet_modtag := [M]
 118
 119 # Default for not multi-part modules
 120 modname = $(basetarget)
 121
 122 $(multi-objs-m)         : modname = $(modname-multi)
 123 $(multi-objs-m:.o=.i)   : modname = $(modname-multi)
 124 $(multi-objs-m:.o=.s)   : modname = $(modname-multi)
 125 $(multi-objs-m:.o=.lst) : modname = $(modname-multi)
 126 $(multi-objs-y)         : modname = $(modname-multi)
 127 $(multi-objs-y:.o=.i)   : modname = $(modname-multi)
 128 $(multi-objs-y:.o=.s)   : modname = $(modname-multi)
 129 $(multi-objs-y:.o=.lst) : modname = $(modname-multi)
 130
 131 quiet_cmd_cc_s_c = CC $(quiet_modtag)  $@
 132 cmd_cc_s_c       = $(CC) $(c_flags) -fverbose-asm -S -o $@ $<
 133
 134 %.s: %.c FORCE
 135         $(call if_changed_dep,cc_s_c)
 136
 137 quiet_cmd_cc_i_c = CPP $(quiet_modtag) $@
 138 cmd_cc_i_c       = $(CPP) $(c_flags)   -o $@ $<
 139
 140 %.i: %.c FORCE
 141         $(call if_changed_dep,cc_i_c)
 142
 143 quiet_cmd_cc_symtypes_c = SYM $(quiet_modtag) $@
 144 cmd_cc_symtypes_c          = \
 145                 $(CPP) -D__GENKSYMS__ $(c_flags) $<                     \
 146                 | $(GENKSYMS) -T $@ >/dev/null;                         \
 147                 test -s $@ || rm -f $@
 148
 149 %.symtypes : %.c FORCE
 150         $(call if_changed_dep,cc_symtypes_c)
 151
 152 # C (.c) files
 153 # The C file is compiled and updated dependency information is generated.
 154 # (See cmd_cc_o_c + relevant part of rule_cc_o_c)
 155
 156 quiet_cmd_cc_o_c = CC $(quiet_modtag)  $@
 157
 158 ifndef CONFIG_MODVERSIONS
 159 cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
 160
 161 else
 162 # When module versioning is enabled the following steps are executed:
 163 # o compile a .tmp_<file>.o from <file>.c
 164 # o if .tmp_<file>.o doesn't contain a __ksymtab version, i.e. does
 165 #   not export symbols, we just rename .tmp_<file>.o to <file>.o and
 166 #   are done.
 167 # o otherwise, we calculate symbol versions using the good old
 168 #   genksyms on the preprocessed source and postprocess them in a way
 169 #   that they are usable as a linker script
 170 # o generate <file>.o from .tmp_<file>.o using the linker to
 171 #   replace the unresolved symbols __crc_exported_symbol with
 172 #   the actual value of the checksum generated by genksyms
 173
 174 cmd_cc_o_c = $(CC) $(c_flags) -c -o $(@D)/.tmp_$(@F) $<
 175 cmd_modversions =                                                       \
 176         if $(OBJDUMP) -h $(@D)/.tmp_$(@F) | grep -q __ksymtab; then     \
 177                 $(CPP) -D__GENKSYMS__ $(c_flags) $<                     \
 178                 | $(GENKSYMS) $(if $(KBUILD_SYMTYPES),                  \
 179                               -T $(@D)/$(@F:.o=.symtypes)) -a $(ARCH)   \
 180                 > $(@D)/.tmp_$(@F:.o=.ver);                             \
 181                                                                         \
 182                 $(LD) $(LDFLAGS) -r -o $@ $(@D)/.tmp_$(@F)              \
 183                         -T $(@D)/.tmp_$(@F:.o=.ver);                    \
 184                 rm -f $(@D)/.tmp_$(@F) $(@D)/.tmp_$(@F:.o=.ver);        \
 185         else                                                            \
 186                 mv -f $(@D)/.tmp_$(@F) $@;                              \
 187         fi;
 188 endif
 189
 190 define rule_cc_o_c
 191         $(call echo-cmd,checksrc) $(cmd_checksrc)                         \
 192         $(call echo-cmd,cc_o_c) $(cmd_cc_o_c);                            \
 193         $(cmd_modversions)                                                \
 194         scripts/basic/fixdep $(depfile) $@ '$(call make-cmd,cc_o_c)' > $(@D)/.$(@F).tmp;  \
 195         rm -f $(depfile);                                                 \
 196         mv -f $(@D)/.$(@F).tmp $(@D)/.$(@F).cmd
 197 endef
 198
 199 # Built-in and composite module parts
 200
 201 %.o: %.c FORCE
 202         $(call cmd,force_checksrc)
 203         $(call if_changed_rule,cc_o_c)
 204
 205 # Single-part modules are special since we need to mark them in $(MODVERDIR)
 206
 207 $(single-used-m): %.o: %.c FORCE
 208         $(call cmd,force_checksrc)
 209         $(call if_changed_rule,cc_o_c)
 210         @{ echo $(@:.o=.ko); echo $@; } > $(MODVERDIR)/$(@F:.o=.mod)
 211
 212 quiet_cmd_cc_lst_c = MKLST   $@
 213       cmd_cc_lst_c = $(CC) $(c_flags) -g -c -o $*.o $< && \
 214                      $(CONFIG_SHELL) $(srctree)/scripts/makelst $*.o \
 215                                      System.map $(OBJDUMP) > $@
 216
 217 %.lst: %.c FORCE
 218         $(call if_changed_dep,cc_lst_c)
 219
 220 # Compile assembler sources (.S)
 221 # ---------------------------------------------------------------------------
 222
 223 modkern_aflags := $(AFLAGS_KERNEL)
 224
 225 $(real-objs-m)      : modkern_aflags := $(AFLAGS_MODULE)
 226 $(real-objs-m:.o=.s): modkern_aflags := $(AFLAGS_MODULE)
 227
 228 quiet_cmd_as_s_S = CPP $(quiet_modtag) $@
 229 cmd_as_s_S       = $(CPP) $(a_flags)   -o $@ $<
 230
 231 %.s: %.S FORCE
 232         $(call if_changed_dep,as_s_S)
 233
 234 quiet_cmd_as_o_S = AS $(quiet_modtag)  $@
 235 cmd_as_o_S       = $(CC) $(a_flags) -c -o $@ $<
 236
 237 %.o: %.S FORCE
 238         $(call if_changed_dep,as_o_S)
 239
 240 targets += $(real-objs-y) $(real-objs-m) $(lib-y)
 241 targets += $(extra-y) $(MAKECMDGOALS) $(always)
 242
 243 # Linker scripts preprocessor (.lds.S -> .lds)
 244 # ---------------------------------------------------------------------------
 245 quiet_cmd_cpp_lds_S = LDS     $@
 246       cmd_cpp_lds_S = $(CPP) $(cpp_flags) -D__ASSEMBLY__ -o $@ $<
 247
 248 %.lds: %.lds.S FORCE
 249         $(call if_changed_dep,cpp_lds_S)
 250
 251 # Build the compiled-in targets
 252 # ---------------------------------------------------------------------------
 253
 254 # To build objects in subdirs, we need to descend into the directories
 255 $(sort $(subdir-obj-y)): $(subdir-ym) ;
 256
 257 #
 258 # Rule to compile a set of .o files into one .o file
 259 #
 260 ifdef builtin-target
 261 quiet_cmd_link_o_target = LD      $@
 262 # If the list of objects to link is empty, just create an empty built-in.o
 263 cmd_link_o_target = $(if $(strip $(obj-y)),\
 264                       $(LD) $(ld_flags) -r -o $@ $(filter $(obj-y), $^),\
 265                       rm -f $@; $(AR) rcs $@)
 266
 267 $(builtin-target): $(obj-y) FORCE
 268         $(call if_changed,link_o_target)
 269
 270 targets += $(builtin-target)
 271 endif # builtin-target
 272
 273 #
 274 # Rule to compile a set of .o files into one .a file
 275 #
 276 ifdef lib-target
 277 quiet_cmd_link_l_target = AR      $@
 278 cmd_link_l_target = rm -f $@; $(AR) $(EXTRA_ARFLAGS) rcs $@ $(lib-y)
 279
 280 $(lib-target): $(lib-y) FORCE
 281         $(call if_changed,link_l_target)
 282
 283 targets += $(lib-target)
 284 endif
 285
 286 #
 287 # Rule to link composite objects
 288 #
 289 #  Composite objects are specified in kbuild makefile as follows:
 290 #    <composite-object>-objs := <list of .o files>
 291 #  or
 292 #    <composite-object>-y    := <list of .o files>
 293 link_multi_deps =                     \
 294 $(filter $(addprefix $(obj)/,         \
 295 $($(subst $(obj)/,,$(@:.o=-objs)))    \
 296 $($(subst $(obj)/,,$(@:.o=-y)))), $^)
 297
 298 quiet_cmd_link_multi-y = LD      $@
 299 cmd_link_multi-y = $(LD) $(ld_flags) -r -o $@ $(link_multi_deps)
 300
 301 quiet_cmd_link_multi-m = LD [M]  $@
 302 cmd_link_multi-m = $(LD) $(ld_flags) $(LDFLAGS_MODULE) -o $@ $(link_multi_deps)
 303
 304 # We would rather have a list of rules like
 305 #       foo.o: $(foo-objs)
 306 # but that's not so easy, so we rather make all composite objects depend
 307 # on the set of all their parts
 308 $(multi-used-y) : %.o: $(multi-objs-y) FORCE
 309         $(call if_changed,link_multi-y)
 310
 311 $(multi-used-m) : %.o: $(multi-objs-m) FORCE
 312         $(call if_changed,link_multi-m)
 313         @{ echo $(@:.o=.ko); echo $(link_multi_deps); } > $(MODVERDIR)/$(@F:.o=.mod)
 314
 315 targets += $(multi-used-y) $(multi-used-m)
 316
 317
 318 # Descending
 319 # ---------------------------------------------------------------------------
 320
 321 PHONY += $(subdir-ym)
 322 $(subdir-ym):
 323         $(Q)$(MAKE) $(build)=$@
 324
 325 # Add FORCE to the prequisites of a target to force it to be always rebuilt.
 326 # ---------------------------------------------------------------------------
 327
 328 PHONY += FORCE
 329
 330 FORCE:
 331
 332 # Read all saved command lines and dependencies for the $(targets) we
 333 # may be building above, using $(if_changed{,_dep}). As an
 334 # optimization, we don't need to read them if the target does not
 335 # exist, we will rebuild anyway in that case.
 336
 337 targets := $(wildcard $(sort $(targets)))
 338 cmd_files := $(wildcard $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
 339
 340 ifneq ($(cmd_files),)
 341   include $(cmd_files)
 342 endif
 343
 344
 345 # Declare the contents of the .PHONY variable as phony.  We keep that
 346 # information in a variable se we can use it in if_changed and friends.
 347
 348 .PHONY: $(PHONY)