tools/build/Makefile.build

   1 # SPDX-License-Identifier: GPL-2.0
   2 ###
   3 # Main build makefile.
   4 #
   5 #  Lots of this code have been borrowed or heavily inspired from parts
   6 #  of kbuild code, which is not credited, but mostly developed by:
   7 #
   8 #  Copyright (C) Sam Ravnborg <sam@mars.ravnborg.org>, 2015
   9 #  Copyright (C) Linus Torvalds <torvalds@linux-foundation.org>, 2015
  10 #
  11
  12 PHONY := __build
  13 __build:
  14
  15 ifeq ($(V),1)
  16   quiet =
  17   Q =
  18 else
  19   quiet=quiet_
  20   Q=@
  21 endif
  22
  23 ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),)
  24   quiet=silent_
  25 endif
  26
  27 build-dir := $(srctree)/tools/build
  28
  29 # Define $(fixdep) for dep-cmd function
  30 ifeq ($(OUTPUT),)
  31   fixdep := $(build-dir)/fixdep
  32 else
  33   fixdep := $(OUTPUT)/fixdep
  34 endif
  35
  36 # Generic definitions
  37 include $(build-dir)/Build.include
  38
  39 # do not force detected configuration
  40 -include $(OUTPUT).config-detected
  41
  42 # Init all relevant variables used in build files so
  43 # 1) they have correct type
  44 # 2) they do not inherit any value from the environment
  45 subdir-y     :=
  46 obj-y        :=
  47 subdir-y     :=
  48 subdir-obj-y :=
  49
  50 # Build definitions
  51 build-file := $(dir)/Build
  52 -include $(build-file)
  53
  54 quiet_cmd_flex  = FLEX     $@
  55 quiet_cmd_bison = BISON    $@
  56
  57 # Create directory unless it exists
  58 quiet_cmd_mkdir = MKDIR    $(dir $@)
  59       cmd_mkdir = mkdir -p $(dir $@)
  60      rule_mkdir = $(if $(wildcard $(dir $@)),,@$(call echo-cmd,mkdir) $(cmd_mkdir))
  61
  62 # Compile command
  63 quiet_cmd_cc_o_c = CC       $@
  64       cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $<
  65
  66 quiet_cmd_host_cc_o_c = HOSTCC   $@
  67       cmd_host_cc_o_c = $(HOSTCC) $(host_c_flags) -c -o $@ $<
  68
  69 quiet_cmd_cxx_o_c = CXX      $@
  70       cmd_cxx_o_c = $(CXX) $(cxx_flags) -c -o $@ $<
  71
  72 quiet_cmd_cpp_i_c = CPP      $@
  73       cmd_cpp_i_c = $(CC) $(c_flags) -E -o $@ $<
  74
  75 quiet_cmd_cc_s_c = AS       $@
  76       cmd_cc_s_c = $(CC) $(c_flags) -S -o $@ $<
  77
  78 quiet_cmd_gen = GEN      $@
  79
  80 # Link agregate command
  81 # If there's nothing to link, create empty $@ object.
  82 quiet_cmd_ld_multi = LD       $@
  83       cmd_ld_multi = $(if $(strip $(obj-y)),\
  84                      $(LD) -r -o $@  $(filter $(obj-y),$^),rm -f $@; $(AR) rcs $@)
  85
  86 quiet_cmd_host_ld_multi = HOSTLD   $@
  87       cmd_host_ld_multi = $(if $(strip $(obj-y)),\
  88                           $(HOSTLD) -r -o $@  $(filter $(obj-y),$^),rm -f $@; $(HOSTAR) rcs $@)
  89
  90 ifneq ($(filter $(obj),$(hostprogs)),)
  91   host = host_
  92 endif
  93
  94 # Build rules
  95 $(OUTPUT)%.o: %.c FORCE
  96         $(call rule_mkdir)
  97         $(call if_changed_dep,$(host)cc_o_c)
  98
  99 $(OUTPUT)%.o: %.cpp FORCE
 100         $(call rule_mkdir)
 101         $(call if_changed_dep,cxx_o_c)
 102
 103 $(OUTPUT)%.o: %.S FORCE
 104         $(call rule_mkdir)
 105         $(call if_changed_dep,$(host)cc_o_c)
 106
 107 $(OUTPUT)%.i: %.c FORCE
 108         $(call rule_mkdir)
 109         $(call if_changed_dep,cpp_i_c)
 110
 111 $(OUTPUT)%.s: %.S FORCE
 112         $(call rule_mkdir)
 113         $(call if_changed_dep,cpp_i_c)
 114
 115 $(OUTPUT)%.s: %.c FORCE
 116         $(call rule_mkdir)
 117         $(call if_changed_dep,cc_s_c)
 118
 119 # Gather build data:
 120 #   obj-y        - list of build objects
 121 #   subdir-y     - list of directories to nest
 122 #   subdir-obj-y - list of directories objects 'dir/$(obj)-in.o'
 123 obj-y        := $($(obj)-y)
 124 subdir-y     := $(patsubst %/,%,$(filter %/, $(obj-y)))
 125 obj-y        := $(patsubst %/, %/$(obj)-in.o, $(obj-y))
 126 subdir-obj-y := $(filter %/$(obj)-in.o, $(obj-y))
 127
 128 # '$(OUTPUT)/dir' prefix to all objects
 129 objprefix    := $(subst ./,,$(OUTPUT)$(dir)/)
 130 obj-y        := $(addprefix $(objprefix),$(obj-y))
 131 subdir-obj-y := $(addprefix $(objprefix),$(subdir-obj-y))
 132
 133 # Final '$(obj)-in.o' object
 134 in-target := $(objprefix)$(obj)-in.o
 135
 136 PHONY += $(subdir-y)
 137
 138 $(subdir-y):
 139         $(Q)$(MAKE) -f $(build-dir)/Makefile.build dir=$(dir)/$@ obj=$(obj)
 140
 141 $(sort $(subdir-obj-y)): $(subdir-y) ;
 142
 143 $(in-target): $(obj-y) FORCE
 144         $(call rule_mkdir)
 145         $(call if_changed,$(host)ld_multi)
 146
 147 __build: $(in-target)
 148         @:
 149
 150 PHONY += FORCE
 151 FORCE:
 152
 153 # Include all cmd files to get all the dependency rules
 154 # for all objects included
 155 targets   := $(wildcard $(sort $(obj-y) $(in-target) $(MAKECMDGOALS)))
 156 cmd_files := $(wildcard $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd))
 157
 158 ifneq ($(cmd_files),)
 159   include $(cmd_files)
 160 endif
 161
 162 .PHONY: $(PHONY)