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 11PHONY := __build 12__build: 13 14ifeq ($(V),1) 15 quiet = 16 Q = 17else 18 quiet=quiet_ 19 Q=@ 20endif 21 22build-dir := $(srctree)/tools/build 23 24# Define $(fixdep) for dep-cmd function 25ifeq ($(OUTPUT),) 26 fixdep := $(build-dir)/fixdep 27else 28 fixdep := $(OUTPUT)/fixdep 29endif 30 31# Generic definitions 32include $(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 40subdir-y := 41obj-y := 42subdir-y := 43subdir-obj-y := 44 45# Build definitions 46build-file := $(dir)/Build 47-include $(build-file) 48 49quiet_cmd_flex = FLEX $@ 50quiet_cmd_bison = BISON $@ 51 52# Create directory unless it exists 53quiet_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 58quiet_cmd_cc_o_c = CC $@ 59 cmd_cc_o_c = $(CC) $(c_flags) -c -o $@ $< 60 61quiet_cmd_host_cc_o_c = HOSTCC $@ 62 cmd_host_cc_o_c = $(HOSTCC) $(host_c_flags) -c -o $@ $< 63 64quiet_cmd_cxx_o_c = CXX $@ 65 cmd_cxx_o_c = $(CXX) $(cxx_flags) -c -o $@ $< 66 67quiet_cmd_cpp_i_c = CPP $@ 68 cmd_cpp_i_c = $(CC) $(c_flags) -E -o $@ $< 69 70quiet_cmd_cc_s_c = AS $@ 71 cmd_cc_s_c = $(CC) $(c_flags) -S -o $@ $< 72 73quiet_cmd_gen = GEN $@ 74 75# Link agregate command 76# If there's nothing to link, create empty $@ object. 77quiet_cmd_ld_multi = LD $@ 78 cmd_ld_multi = $(if $(strip $(obj-y)),\ 79 $(LD) -r -o $@ $(filter $(obj-y),$^),rm -f $@; $(AR) rcs $@) 80 81quiet_cmd_host_ld_multi = HOSTLD $@ 82 cmd_host_ld_multi = $(if $(strip $(obj-y)),\ 83 $(HOSTLD) -r -o $@ $(filter $(obj-y),$^),rm -f $@; $(HOSTAR) rcs $@) 84 85ifneq ($(filter $(obj),$(hostprogs)),) 86 host = host_ 87endif 88 89# Build rules 90$(OUTPUT)%.o: %.c FORCE 91 $(call rule_mkdir) 92 $(call if_changed_dep,$(host)cc_o_c) 93 94$(OUTPUT)%.o: %.cpp FORCE 95 $(call rule_mkdir) 96 $(call if_changed_dep,cxx_o_c) 97 98$(OUTPUT)%.o: %.S FORCE 99 $(call rule_mkdir) 100 $(call if_changed_dep,$(host)cc_o_c) 101 102$(OUTPUT)%.i: %.c FORCE 103 $(call rule_mkdir) 104 $(call if_changed_dep,cpp_i_c) 105 106$(OUTPUT)%.s: %.S FORCE 107 $(call rule_mkdir) 108 $(call if_changed_dep,cpp_i_c) 109 110$(OUTPUT)%.s: %.c FORCE 111 $(call rule_mkdir) 112 $(call if_changed_dep,cc_s_c) 113 114# Gather build data: 115# obj-y - list of build objects 116# subdir-y - list of directories to nest 117# subdir-obj-y - list of directories objects 'dir/$(obj)-in.o' 118obj-y := $($(obj)-y) 119subdir-y := $(patsubst %/,%,$(filter %/, $(obj-y))) 120obj-y := $(patsubst %/, %/$(obj)-in.o, $(obj-y)) 121subdir-obj-y := $(filter %/$(obj)-in.o, $(obj-y)) 122 123# '$(OUTPUT)/dir' prefix to all objects 124objprefix := $(subst ./,,$(OUTPUT)$(dir)/) 125obj-y := $(addprefix $(objprefix),$(obj-y)) 126subdir-obj-y := $(addprefix $(objprefix),$(subdir-obj-y)) 127 128# Final '$(obj)-in.o' object 129in-target := $(objprefix)$(obj)-in.o 130 131PHONY += $(subdir-y) 132 133$(subdir-y): 134 $(Q)$(MAKE) -f $(build-dir)/Makefile.build dir=$(dir)/$@ obj=$(obj) 135 136$(sort $(subdir-obj-y)): $(subdir-y) ; 137 138$(in-target): $(obj-y) FORCE 139 $(call rule_mkdir) 140 $(call if_changed,$(host)ld_multi) 141 142__build: $(in-target) 143 @: 144 145PHONY += FORCE 146FORCE: 147 148# Include all cmd files to get all the dependency rules 149# for all objects included 150targets := $(wildcard $(sort $(obj-y) $(in-target) $(MAKECMDGOALS))) 151cmd_files := $(wildcard $(foreach f,$(targets),$(dir $(f)).$(notdir $(f)).cmd)) 152 153ifneq ($(cmd_files),) 154 include $(cmd_files) 155endif 156 157.PHONY: $(PHONY) 158