tools/build/Makefile.build

   1 ###
   2 # Main build makefile.
   3 #
   4 #  Lots of this code have been borrowed or heavily inspired from parts
   5 #  of kbuild code, which is not credited, but mostly developed by:
   6 #
   7 #  Copyright (C) Sam Ravnborg <sam@mars.ravnborg.org>, 2015
   8 #  Copyright (C) Linus Torvalds <torvalds@linux-foundation.org>, 2015
   9 #
  10
  11 PHONY := __build
  12 __build:
  13
  14 ifeq ($(V),1)
  15   quiet =
  16   Q =
  17 else
  18   quiet=quiet_
  19   Q=@
  20 endif
  21
  22 build-dir := $(srctree)/tools/build
  23
  24 # Define $(fixdep) for dep-cmd function
  25 ifeq ($(OUTPUT),)
  26   fixdep := $(build-dir)/fixdep
  27 else
  28   fixdep := $(OUTPUT)/fixdep
  29 endif
  30
  31 # Generic definitions
  32 include $(build-dir)/Build.include
  33
  34 # do not force detected configuration
  35 -include $(OUTPUT).config-detected
  36
  37 # Init all relevant variables used in build files so
  38 # 1) they have correct type
  39 # 2) they do not inherit any value from the environment
  40 subdir-y     :=
  41 obj-y        :=
  42 subdir-y     :=
  43 subdir-obj-y :=
  44
  45 # Build definitions
  46 build-file := $(dir)/Build
  47 -include $(build-file)
  48
  49 quiet_cmd_flex  = FLEX     $@
  50 quiet_cmd_bison = BISON    $@
  51
  52 # Create directory unless it exists
  53 quiet_cmd_mkdir = MKDIR    $(dir $@)
  54       cmd_mkdir = mkdir -p $(dir $@)
  55      rule_mkdir = $(if $(wildcard $(dir $@)),,@$(call echo-cmd,mkdir) $(cmd_mkdir))
  56
  57 # Compile command
  58 quiet_cmd_cc_o_c = CC       $@
  59       cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
  60
  61 quiet_cmd_cc_i_c = CPP      $@
  62       cmd_cc_i_c = $(CC) $(c_flags) -E -o $@ $<
  63
  64 quiet_cmd_cc_s_c = AS       $@
  65       cmd_cc_s_c = $(CC) $(c_flags) -S -o $@ $<
  66
  67 quiet_cmd_gen = GEN      $@
  68
  69 # Link agregate command
  70 # If there's nothing to link, create empty $@ object.
  71 quiet_cmd_ld_multi = LD       $@
  72       cmd_ld_multi = $(if $(strip $(obj-y)),\
  73                        $(LD) -r -o $@  $(filter $(obj-y),$^),rm -f $@; $(AR) rcs $@)
  74
  75 # Build rules
  76 $(OUTPUT)%.o: %.c FORCE
  77         $(call rule_mkdir)
  78         $(call if_changed_dep,cc_o_c)
  79
  80 $(OUTPUT)%.o: %.S FORCE
  81         $(call rule_mkdir)
  82         $(call if_changed_dep,cc_o_c)
  83
  84 $(OUTPUT)%.i: %.c FORCE
  85         $(call rule_mkdir)
  86         $(call if_changed_dep,cc_i_c)
  87
  88 $(OUTPUT)%.s: %.S FORCE
  89         $(call rule_mkdir)
  90         $(call if_changed_dep,cc_i_c)
  91
  92 $(OUTPUT)%.s: %.c FORCE
  93         $(call rule_mkdir)
  94         $(call if_changed_dep,cc_s_c)
  95
  96 # Gather build data:
  97 #   obj-y        - list of build objects
  98 #   subdir-y     - list of directories to nest
  99 #   subdir-obj-y - list of directories objects 'dir/$(obj)-in.o'
 100 obj-y        := $($(obj)-y)
 101 subdir-y     := $(patsubst %/,%,$(filter %/, $(obj-y)))
 102 obj-y        := $(patsubst %/, %/$(obj)-in.o, $(obj-y))
 103 subdir-obj-y := $(filter %/$(obj)-in.o, $(obj-y))
 104
 105 # '$(OUTPUT)/dir' prefix to all objects
 106 objprefix    := $(subst ./,,$(OUTPUT)$(dir)/)
 107 obj-y        := $(addprefix $(objprefix),$(obj-y))
 108 subdir-obj-y := $(addprefix $(objprefix),$(subdir-obj-y))
 109
 110 # Final '$(obj)-in.o' object
 111 in-target := $(objprefix)$(obj)-in.o
 112
 113 PHONY += $(subdir-y)
 114
 115 $(subdir-y):
 116         $(Q)$(MAKE) -f $(build-dir)/Makefile.build dir=$(dir)/$@ obj=$(obj)
 117
 118 $(sort $(subdir-obj-y)): $(subdir-y) ;
 119
 120 $(in-target): $(obj-y) FORCE
 121         $(call rule_mkdir)
 122         $(call if_changed,ld_multi)
 123
 124 __build: $(in-target)
 125         @:
 126
 127 PHONY += FORCE
 128 FORCE:
 129
 130 # Include all cmd files to get all the dependency rules
 131 # for all objects included
 132 targets   := $(wildcard $(sort $(obj-y) $(in-target) $(MAKECMDGOALS)))
 133 cmd_files := $(wildcard $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
 134
 135 ifneq ($(cmd_files),)
 136   include $(cmd_files)
 137 endif
 138
 139 .PHONY: $(PHONY)