1# SPDX-License-Identifier: GPL-2.0 2# Backward compatibility 3asflags-y += $(EXTRA_AFLAGS) 4ccflags-y += $(EXTRA_CFLAGS) 5cppflags-y += $(EXTRA_CPPFLAGS) 6ldflags-y += $(EXTRA_LDFLAGS) 7 8# flags that take effect in current and sub directories 9KBUILD_AFLAGS += $(subdir-asflags-y) 10KBUILD_CFLAGS += $(subdir-ccflags-y) 11 12# Figure out what we need to build from the various variables 13# =========================================================================== 14 15# When an object is listed to be built compiled-in and modular, 16# only build the compiled-in version 17obj-m := $(filter-out $(obj-y),$(obj-m)) 18 19# Libraries are always collected in one lib file. 20# Filter out objects already built-in 21lib-y := $(filter-out $(obj-y), $(sort $(lib-y) $(lib-m))) 22 23# Determine modorder. 24# Unfortunately, we don't have information about ordering between -y 25# and -m subdirs. Just put -y's first. 26modorder := $(patsubst %/,%/modules.order, $(filter %/, $(obj-y)) $(obj-m:.o=.ko)) 27 28# Handle objects in subdirs 29# --------------------------------------------------------------------------- 30# o if we encounter foo/ in $(obj-y), replace it by foo/built-in.a 31# and add the directory to the list of dirs to descend into: $(subdir-y) 32# o if we encounter foo/ in $(obj-m), remove it from $(obj-m) 33# and add the directory to the list of dirs to descend into: $(subdir-m) 34__subdir-y := $(patsubst %/,%,$(filter %/, $(obj-y))) 35subdir-y += $(__subdir-y) 36__subdir-m := $(patsubst %/,%,$(filter %/, $(obj-m))) 37subdir-m += $(__subdir-m) 38obj-y := $(patsubst %/, %/built-in.a, $(obj-y)) 39obj-m := $(filter-out %/, $(obj-m)) 40 41# Subdirectories we need to descend into 42subdir-ym := $(sort $(subdir-y) $(subdir-m)) 43 44# if $(foo-objs), $(foo-y), or $(foo-m) exists, foo.o is a composite object 45multi-used-y := $(sort $(foreach m,$(obj-y), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))), $(m)))) 46multi-used-m := $(sort $(foreach m,$(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m))), $(m)))) 47multi-used := $(multi-used-y) $(multi-used-m) 48 49# $(subdir-obj-y) is the list of objects in $(obj-y) which uses dir/ to 50# tell kbuild to descend 51subdir-obj-y := $(filter %/built-in.a, $(obj-y)) 52 53# Replace multi-part objects by their individual parts, 54# including built-in.a from subdirectories 55real-obj-y := $(foreach m, $(obj-y), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))),$($(m:.o=-objs)) $($(m:.o=-y)),$(m))) 56real-obj-m := $(foreach m, $(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m))),$($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m)),$(m))) 57 58# DTB 59# If CONFIG_OF_ALL_DTBS is enabled, all DT blobs are built 60extra-y += $(dtb-y) 61extra-$(CONFIG_OF_ALL_DTBS) += $(dtb-) 62 63ifneq ($(CHECK_DTBS),) 64extra-y += $(patsubst %.dtb,%.dt.yaml, $(dtb-y)) 65extra-$(CONFIG_OF_ALL_DTBS) += $(patsubst %.dtb,%.dt.yaml, $(dtb-)) 66endif 67 68# Test self-contained headers 69 70# Wildcard searches in $(srctree)/$(src)/, but not in $(objtree)/$(obj)/. 71# Stale generated headers are often left over, so pattern matching should 72# be avoided. Please notice $(srctree)/$(src)/ and $(objtree)/$(obj) point 73# to the same location for in-tree building. So, header-test-pattern-y should 74# be used with care. 75header-test-y += $(filter-out $(header-test-), \ 76 $(patsubst $(srctree)/$(src)/%, %, \ 77 $(wildcard $(addprefix $(srctree)/$(src)/, \ 78 $(header-test-pattern-y))))) 79 80extra-$(CONFIG_HEADER_TEST) += $(addsuffix .s, $(header-test-y) $(header-test-m)) 81 82# Add subdir path 83 84extra-y := $(addprefix $(obj)/,$(extra-y)) 85always := $(addprefix $(obj)/,$(always)) 86targets := $(addprefix $(obj)/,$(targets)) 87modorder := $(addprefix $(obj)/,$(modorder)) 88obj-m := $(addprefix $(obj)/,$(obj-m)) 89lib-y := $(addprefix $(obj)/,$(lib-y)) 90subdir-obj-y := $(addprefix $(obj)/,$(subdir-obj-y)) 91real-obj-y := $(addprefix $(obj)/,$(real-obj-y)) 92real-obj-m := $(addprefix $(obj)/,$(real-obj-m)) 93multi-used-m := $(addprefix $(obj)/,$(multi-used-m)) 94subdir-ym := $(addprefix $(obj)/,$(subdir-ym)) 95 96# Finds the multi-part object the current object will be linked into. 97# If the object belongs to two or more multi-part objects, all of them are 98# concatenated with a colon separator. 99modname-multi = $(subst $(space),:,$(sort $(foreach m,$(multi-used),\ 100 $(if $(filter $*.o, $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m))),$(m:.o=))))) 101 102modname = $(if $(modname-multi),$(modname-multi),$(basetarget)) 103 104# These flags are needed for modversions and compiling, so we define them here 105# $(modname_flags) defines KBUILD_MODNAME as the name of the module it will 106# end up in (or would, if it gets compiled in) 107name-fix = $(squote)$(quote)$(subst $(comma),_,$(subst -,_,$1))$(quote)$(squote) 108basename_flags = -DKBUILD_BASENAME=$(call name-fix,$(basetarget)) 109modname_flags = -DKBUILD_MODNAME=$(call name-fix,$(modname)) 110 111orig_c_flags = $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) \ 112 $(ccflags-y) $(CFLAGS_$(basetarget).o) 113_c_flags = $(filter-out $(CFLAGS_REMOVE_$(basetarget).o), $(orig_c_flags)) 114orig_a_flags = $(KBUILD_CPPFLAGS) $(KBUILD_AFLAGS) \ 115 $(asflags-y) $(AFLAGS_$(basetarget).o) 116_a_flags = $(filter-out $(AFLAGS_REMOVE_$(basetarget).o), $(orig_a_flags)) 117_cpp_flags = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$(@F)) 118 119# 120# Enable gcov profiling flags for a file, directory or for all files depending 121# on variables GCOV_PROFILE_obj.o, GCOV_PROFILE and CONFIG_GCOV_PROFILE_ALL 122# (in this order) 123# 124ifeq ($(CONFIG_GCOV_KERNEL),y) 125_c_flags += $(if $(patsubst n%,, \ 126 $(GCOV_PROFILE_$(basetarget).o)$(GCOV_PROFILE)$(CONFIG_GCOV_PROFILE_ALL)), \ 127 $(CFLAGS_GCOV)) 128endif 129 130# 131# Enable address sanitizer flags for kernel except some files or directories 132# we don't want to check (depends on variables KASAN_SANITIZE_obj.o, KASAN_SANITIZE) 133# 134ifeq ($(CONFIG_KASAN),y) 135_c_flags += $(if $(patsubst n%,, \ 136 $(KASAN_SANITIZE_$(basetarget).o)$(KASAN_SANITIZE)y), \ 137 $(CFLAGS_KASAN), $(CFLAGS_KASAN_NOSANITIZE)) 138endif 139 140ifeq ($(CONFIG_UBSAN),y) 141_c_flags += $(if $(patsubst n%,, \ 142 $(UBSAN_SANITIZE_$(basetarget).o)$(UBSAN_SANITIZE)$(CONFIG_UBSAN_SANITIZE_ALL)), \ 143 $(CFLAGS_UBSAN)) 144endif 145 146ifeq ($(CONFIG_KCOV),y) 147_c_flags += $(if $(patsubst n%,, \ 148 $(KCOV_INSTRUMENT_$(basetarget).o)$(KCOV_INSTRUMENT)$(CONFIG_KCOV_INSTRUMENT_ALL)), \ 149 $(CFLAGS_KCOV)) 150endif 151 152# $(srctree)/$(src) for including checkin headers from generated source files 153# $(objtree)/$(obj) for including generated headers from checkin source files 154ifeq ($(KBUILD_EXTMOD),) 155ifdef building_out_of_srctree 156_c_flags += -I $(srctree)/$(src) -I $(objtree)/$(obj) 157_a_flags += -I $(srctree)/$(src) -I $(objtree)/$(obj) 158_cpp_flags += -I $(srctree)/$(src) -I $(objtree)/$(obj) 159endif 160endif 161 162c_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ 163 -include $(srctree)/include/linux/compiler_types.h \ 164 $(_c_flags) $(modkern_cflags) \ 165 $(basename_flags) $(modname_flags) 166 167a_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ 168 $(_a_flags) $(modkern_aflags) 169 170cpp_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ 171 $(_cpp_flags) 172 173ld_flags = $(KBUILD_LDFLAGS) $(ldflags-y) $(LDFLAGS_$(@F)) 174 175DTC_INCLUDE := $(srctree)/scripts/dtc/include-prefixes 176 177dtc_cpp_flags = -Wp,-MD,$(depfile).pre.tmp -nostdinc \ 178 $(addprefix -I,$(DTC_INCLUDE)) \ 179 -undef -D__DTS__ 180 181# Useful for describing the dependency of composite objects 182# Usage: 183# $(call multi_depend, multi_used_targets, suffix_to_remove, suffix_to_add) 184define multi_depend 185$(foreach m, $(notdir $1), \ 186 $(eval $(obj)/$m: \ 187 $(addprefix $(obj)/, $(foreach s, $3, $($(m:%$(strip $2)=%$(s))))))) 188endef 189 190# LEX 191# --------------------------------------------------------------------------- 192quiet_cmd_flex = LEX $@ 193 cmd_flex = $(LEX) -o$@ -L $< 194 195$(obj)/%.lex.c: $(src)/%.l FORCE 196 $(call if_changed,flex) 197 198# YACC 199# --------------------------------------------------------------------------- 200quiet_cmd_bison = YACC $@ 201 cmd_bison = $(YACC) -o$@ -t -l $< 202 203$(obj)/%.tab.c: $(src)/%.y FORCE 204 $(call if_changed,bison) 205 206quiet_cmd_bison_h = YACC $@ 207 cmd_bison_h = $(YACC) -o/dev/null --defines=$@ -t -l $< 208 209$(obj)/%.tab.h: $(src)/%.y FORCE 210 $(call if_changed,bison_h) 211 212# Shipped files 213# =========================================================================== 214 215quiet_cmd_shipped = SHIPPED $@ 216cmd_shipped = cat $< > $@ 217 218$(obj)/%: $(src)/%_shipped 219 $(call cmd,shipped) 220 221# Commands useful for building a boot image 222# =========================================================================== 223# 224# Use as following: 225# 226# target: source(s) FORCE 227# $(if_changed,ld/objcopy/gzip) 228# 229# and add target to extra-y so that we know we have to 230# read in the saved command line 231 232# Linking 233# --------------------------------------------------------------------------- 234 235quiet_cmd_ld = LD $@ 236 cmd_ld = $(LD) $(ld_flags) $(real-prereqs) -o $@ 237 238# Archive 239# --------------------------------------------------------------------------- 240 241quiet_cmd_ar = AR $@ 242 cmd_ar = rm -f $@; $(AR) rcsTP$(KBUILD_ARFLAGS) $@ $(real-prereqs) 243 244# Objcopy 245# --------------------------------------------------------------------------- 246 247quiet_cmd_objcopy = OBJCOPY $@ 248cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $(OBJCOPYFLAGS_$(@F)) $< $@ 249 250# Gzip 251# --------------------------------------------------------------------------- 252 253quiet_cmd_gzip = GZIP $@ 254 cmd_gzip = cat $(real-prereqs) | gzip -n -f -9 > $@ 255 256# DTC 257# --------------------------------------------------------------------------- 258DTC ?= $(objtree)/scripts/dtc/dtc 259 260# Disable noisy checks by default 261ifeq ($(findstring 1,$(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),) 262DTC_FLAGS += -Wno-unit_address_vs_reg \ 263 -Wno-unit_address_format \ 264 -Wno-avoid_unnecessary_addr_size \ 265 -Wno-alias_paths \ 266 -Wno-graph_child_address \ 267 -Wno-simple_bus_reg \ 268 -Wno-unique_unit_address \ 269 -Wno-pci_device_reg 270endif 271 272ifneq ($(findstring 2,$(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),) 273DTC_FLAGS += -Wnode_name_chars_strict \ 274 -Wproperty_name_chars_strict 275endif 276 277DTC_FLAGS += $(DTC_FLAGS_$(basetarget)) 278 279# Generate an assembly file to wrap the output of the device tree compiler 280quiet_cmd_dt_S_dtb= DTB $@ 281cmd_dt_S_dtb= \ 282{ \ 283 echo '\#include <asm-generic/vmlinux.lds.h>'; \ 284 echo '.section .dtb.init.rodata,"a"'; \ 285 echo '.balign STRUCT_ALIGNMENT'; \ 286 echo '.global __dtb_$(subst -,_,$(*F))_begin'; \ 287 echo '__dtb_$(subst -,_,$(*F))_begin:'; \ 288 echo '.incbin "$<" '; \ 289 echo '__dtb_$(subst -,_,$(*F))_end:'; \ 290 echo '.global __dtb_$(subst -,_,$(*F))_end'; \ 291 echo '.balign STRUCT_ALIGNMENT'; \ 292} > $@ 293 294$(obj)/%.dtb.S: $(obj)/%.dtb FORCE 295 $(call if_changed,dt_S_dtb) 296 297quiet_cmd_dtc = DTC $@ 298cmd_dtc = mkdir -p $(dir ${dtc-tmp}) ; \ 299 $(HOSTCC) -E $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $< ; \ 300 $(DTC) -O $(2) -o $@ -b 0 \ 301 $(addprefix -i,$(dir $<) $(DTC_INCLUDE)) $(DTC_FLAGS) \ 302 -d $(depfile).dtc.tmp $(dtc-tmp) ; \ 303 cat $(depfile).pre.tmp $(depfile).dtc.tmp > $(depfile) 304 305$(obj)/%.dtb: $(src)/%.dts $(DTC) FORCE 306 $(call if_changed_dep,dtc,dtb) 307 308DT_CHECKER ?= dt-validate 309DT_BINDING_DIR := Documentation/devicetree/bindings 310DT_TMP_SCHEMA := $(objtree)/$(DT_BINDING_DIR)/processed-schema.yaml 311 312quiet_cmd_dtb_check = CHECK $@ 313 cmd_dtb_check = $(DT_CHECKER) -u $(srctree)/$(DT_BINDING_DIR) -p $(DT_TMP_SCHEMA) $@ ; 314 315define rule_dtc_dt_yaml 316 $(call cmd_and_fixdep,dtc,yaml) 317 $(call cmd,dtb_check) 318endef 319 320$(obj)/%.dt.yaml: $(src)/%.dts $(DTC) $(DT_TMP_SCHEMA) FORCE 321 $(call if_changed_rule,dtc_dt_yaml) 322 323dtc-tmp = $(subst $(comma),_,$(dot-target).dts.tmp) 324 325# Bzip2 326# --------------------------------------------------------------------------- 327 328# Bzip2 and LZMA do not include size in file... so we have to fake that; 329# append the size as a 32-bit littleendian number as gzip does. 330size_append = printf $(shell \ 331dec_size=0; \ 332for F in $(real-prereqs); do \ 333 fsize=$$($(CONFIG_SHELL) $(srctree)/scripts/file-size.sh $$F); \ 334 dec_size=$$(expr $$dec_size + $$fsize); \ 335done; \ 336printf "%08x\n" $$dec_size | \ 337 sed 's/\(..\)/\1 /g' | { \ 338 read ch0 ch1 ch2 ch3; \ 339 for ch in $$ch3 $$ch2 $$ch1 $$ch0; do \ 340 printf '%s%03o' '\\' $$((0x$$ch)); \ 341 done; \ 342 } \ 343) 344 345quiet_cmd_bzip2 = BZIP2 $@ 346 cmd_bzip2 = { cat $(real-prereqs) | bzip2 -9; $(size_append); } > $@ 347 348# Lzma 349# --------------------------------------------------------------------------- 350 351quiet_cmd_lzma = LZMA $@ 352 cmd_lzma = { cat $(real-prereqs) | lzma -9; $(size_append); } > $@ 353 354quiet_cmd_lzo = LZO $@ 355 cmd_lzo = { cat $(real-prereqs) | lzop -9; $(size_append); } > $@ 356 357quiet_cmd_lz4 = LZ4 $@ 358 cmd_lz4 = { cat $(real-prereqs) | lz4c -l -c1 stdin stdout; \ 359 $(size_append); } > $@ 360 361# U-Boot mkimage 362# --------------------------------------------------------------------------- 363 364MKIMAGE := $(srctree)/scripts/mkuboot.sh 365 366# SRCARCH just happens to match slightly more than ARCH (on sparc), so reduces 367# the number of overrides in arch makefiles 368UIMAGE_ARCH ?= $(SRCARCH) 369UIMAGE_COMPRESSION ?= $(if $(2),$(2),none) 370UIMAGE_OPTS-y ?= 371UIMAGE_TYPE ?= kernel 372UIMAGE_LOADADDR ?= arch_must_set_this 373UIMAGE_ENTRYADDR ?= $(UIMAGE_LOADADDR) 374UIMAGE_NAME ?= 'Linux-$(KERNELRELEASE)' 375 376quiet_cmd_uimage = UIMAGE $@ 377 cmd_uimage = $(CONFIG_SHELL) $(MKIMAGE) -A $(UIMAGE_ARCH) -O linux \ 378 -C $(UIMAGE_COMPRESSION) $(UIMAGE_OPTS-y) \ 379 -T $(UIMAGE_TYPE) \ 380 -a $(UIMAGE_LOADADDR) -e $(UIMAGE_ENTRYADDR) \ 381 -n $(UIMAGE_NAME) -d $< $@ 382 383# XZ 384# --------------------------------------------------------------------------- 385# Use xzkern to compress the kernel image and xzmisc to compress other things. 386# 387# xzkern uses a big LZMA2 dictionary since it doesn't increase memory usage 388# of the kernel decompressor. A BCJ filter is used if it is available for 389# the target architecture. xzkern also appends uncompressed size of the data 390# using size_append. The .xz format has the size information available at 391# the end of the file too, but it's in more complex format and it's good to 392# avoid changing the part of the boot code that reads the uncompressed size. 393# Note that the bytes added by size_append will make the xz tool think that 394# the file is corrupt. This is expected. 395# 396# xzmisc doesn't use size_append, so it can be used to create normal .xz 397# files. xzmisc uses smaller LZMA2 dictionary than xzkern, because a very 398# big dictionary would increase the memory usage too much in the multi-call 399# decompression mode. A BCJ filter isn't used either. 400quiet_cmd_xzkern = XZKERN $@ 401 cmd_xzkern = { cat $(real-prereqs) | sh $(srctree)/scripts/xz_wrap.sh; \ 402 $(size_append); } > $@ 403 404quiet_cmd_xzmisc = XZMISC $@ 405 cmd_xzmisc = cat $(real-prereqs) | xz --check=crc32 --lzma2=dict=1MiB > $@ 406 407# ASM offsets 408# --------------------------------------------------------------------------- 409 410# Default sed regexp - multiline due to syntax constraints 411# 412# Use [:space:] because LLVM's integrated assembler inserts <tab> around 413# the .ascii directive whereas GCC keeps the <space> as-is. 414define sed-offsets 415 's:^[[:space:]]*\.ascii[[:space:]]*"\(.*\)".*:\1:; \ 416 /^->/{s:->#\(.*\):/* \1 */:; \ 417 s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \ 418 s:->::; p;}' 419endef 420 421# Use filechk to avoid rebuilds when a header changes, but the resulting file 422# does not 423define filechk_offsets 424 echo "#ifndef $2"; \ 425 echo "#define $2"; \ 426 echo "/*"; \ 427 echo " * DO NOT MODIFY."; \ 428 echo " *"; \ 429 echo " * This file was generated by Kbuild"; \ 430 echo " */"; \ 431 echo ""; \ 432 sed -ne $(sed-offsets) < $<; \ 433 echo ""; \ 434 echo "#endif" 435endef 436