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) 48single-used-m := $(sort $(filter-out $(multi-used-m),$(obj-m))) 49 50# $(subdir-obj-y) is the list of objects in $(obj-y) which uses dir/ to 51# tell kbuild to descend 52subdir-obj-y := $(filter %/built-in.a, $(obj-y)) 53 54# Replace multi-part objects by their individual parts, 55# including built-in.a from subdirectories 56real-obj-y := $(foreach m, $(obj-y), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))),$($(m:.o=-objs)) $($(m:.o=-y)),$(m))) 57real-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))) 58 59# DTB 60# If CONFIG_OF_ALL_DTBS is enabled, all DT blobs are built 61extra-y += $(dtb-y) 62extra-$(CONFIG_OF_ALL_DTBS) += $(dtb-) 63 64ifneq ($(CHECK_DTBS),) 65extra-y += $(patsubst %.dtb,%.dt.yaml, $(dtb-y)) 66extra-$(CONFIG_OF_ALL_DTBS) += $(patsubst %.dtb,%.dt.yaml, $(dtb-)) 67endif 68 69# Test self-contained headers 70 71# Wildcard searches in $(srctree)/$(src)/, but not in $(objtree)/$(obj)/. 72# Stale generated headers are often left over, so pattern matching should 73# be avoided. Please notice $(srctree)/$(src)/ and $(objtree)/$(obj) point 74# to the same location for in-tree building. So, header-test-pattern-y should 75# be used with care. 76header-test-y += $(filter-out $(header-test-), \ 77 $(patsubst $(srctree)/$(src)/%, %, \ 78 $(wildcard $(addprefix $(srctree)/$(src)/, \ 79 $(header-test-pattern-y))))) 80 81extra-$(CONFIG_HEADER_TEST) += $(addsuffix .s, $(header-test-y) $(header-test-m)) 82 83# Add subdir path 84 85extra-y := $(addprefix $(obj)/,$(extra-y)) 86always := $(addprefix $(obj)/,$(always)) 87targets := $(addprefix $(obj)/,$(targets)) 88modorder := $(addprefix $(obj)/,$(modorder)) 89obj-m := $(addprefix $(obj)/,$(obj-m)) 90lib-y := $(addprefix $(obj)/,$(lib-y)) 91subdir-obj-y := $(addprefix $(obj)/,$(subdir-obj-y)) 92real-obj-y := $(addprefix $(obj)/,$(real-obj-y)) 93real-obj-m := $(addprefix $(obj)/,$(real-obj-m)) 94single-used-m := $(addprefix $(obj)/,$(single-used-m)) 95multi-used-m := $(addprefix $(obj)/,$(multi-used-m)) 96subdir-ym := $(addprefix $(obj)/,$(subdir-ym)) 97 98# Finds the multi-part object the current object will be linked into. 99# If the object belongs to two or more multi-part objects, all of them are 100# concatenated with a colon separator. 101modname-multi = $(subst $(space),:,$(sort $(foreach m,$(multi-used),\ 102 $(if $(filter $*.o, $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m))),$(m:.o=))))) 103 104modname = $(if $(modname-multi),$(modname-multi),$(basetarget)) 105 106# These flags are needed for modversions and compiling, so we define them here 107# $(modname_flags) defines KBUILD_MODNAME as the name of the module it will 108# end up in (or would, if it gets compiled in) 109name-fix = $(squote)$(quote)$(subst $(comma),_,$(subst -,_,$1))$(quote)$(squote) 110basename_flags = -DKBUILD_BASENAME=$(call name-fix,$(basetarget)) 111modname_flags = -DKBUILD_MODNAME=$(call name-fix,$(modname)) 112 113orig_c_flags = $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) \ 114 $(ccflags-y) $(CFLAGS_$(basetarget).o) 115_c_flags = $(filter-out $(CFLAGS_REMOVE_$(basetarget).o), $(orig_c_flags)) 116orig_a_flags = $(KBUILD_CPPFLAGS) $(KBUILD_AFLAGS) \ 117 $(asflags-y) $(AFLAGS_$(basetarget).o) 118_a_flags = $(filter-out $(AFLAGS_REMOVE_$(basetarget).o), $(orig_a_flags)) 119_cpp_flags = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$(@F)) 120 121# 122# Enable gcov profiling flags for a file, directory or for all files depending 123# on variables GCOV_PROFILE_obj.o, GCOV_PROFILE and CONFIG_GCOV_PROFILE_ALL 124# (in this order) 125# 126ifeq ($(CONFIG_GCOV_KERNEL),y) 127_c_flags += $(if $(patsubst n%,, \ 128 $(GCOV_PROFILE_$(basetarget).o)$(GCOV_PROFILE)$(CONFIG_GCOV_PROFILE_ALL)), \ 129 $(CFLAGS_GCOV)) 130endif 131 132# 133# Enable address sanitizer flags for kernel except some files or directories 134# we don't want to check (depends on variables KASAN_SANITIZE_obj.o, KASAN_SANITIZE) 135# 136ifeq ($(CONFIG_KASAN),y) 137_c_flags += $(if $(patsubst n%,, \ 138 $(KASAN_SANITIZE_$(basetarget).o)$(KASAN_SANITIZE)y), \ 139 $(CFLAGS_KASAN), $(CFLAGS_KASAN_NOSANITIZE)) 140endif 141 142ifeq ($(CONFIG_UBSAN),y) 143_c_flags += $(if $(patsubst n%,, \ 144 $(UBSAN_SANITIZE_$(basetarget).o)$(UBSAN_SANITIZE)$(CONFIG_UBSAN_SANITIZE_ALL)), \ 145 $(CFLAGS_UBSAN)) 146endif 147 148ifeq ($(CONFIG_KCOV),y) 149_c_flags += $(if $(patsubst n%,, \ 150 $(KCOV_INSTRUMENT_$(basetarget).o)$(KCOV_INSTRUMENT)$(CONFIG_KCOV_INSTRUMENT_ALL)), \ 151 $(CFLAGS_KCOV)) 152endif 153 154# $(srctree)/$(src) for including checkin headers from generated source files 155# $(objtree)/$(obj) for including generated headers from checkin source files 156ifeq ($(KBUILD_EXTMOD),) 157ifdef building_out_of_srctree 158_c_flags += -I $(srctree)/$(src) -I $(objtree)/$(obj) 159_a_flags += -I $(srctree)/$(src) -I $(objtree)/$(obj) 160_cpp_flags += -I $(srctree)/$(src) -I $(objtree)/$(obj) 161endif 162endif 163 164c_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ 165 -include $(srctree)/include/linux/compiler_types.h \ 166 $(_c_flags) $(modkern_cflags) \ 167 $(basename_flags) $(modname_flags) 168 169a_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ 170 $(_a_flags) $(modkern_aflags) 171 172cpp_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ 173 $(_cpp_flags) 174 175ld_flags = $(KBUILD_LDFLAGS) $(ldflags-y) $(LDFLAGS_$(@F)) 176 177DTC_INCLUDE := $(srctree)/scripts/dtc/include-prefixes 178 179dtc_cpp_flags = -Wp,-MD,$(depfile).pre.tmp -nostdinc \ 180 $(addprefix -I,$(DTC_INCLUDE)) \ 181 -undef -D__DTS__ 182 183# Useful for describing the dependency of composite objects 184# Usage: 185# $(call multi_depend, multi_used_targets, suffix_to_remove, suffix_to_add) 186define multi_depend 187$(foreach m, $(notdir $1), \ 188 $(eval $(obj)/$m: \ 189 $(addprefix $(obj)/, $(foreach s, $3, $($(m:%$(strip $2)=%$(s))))))) 190endef 191 192# LEX 193# --------------------------------------------------------------------------- 194quiet_cmd_flex = LEX $@ 195 cmd_flex = $(LEX) -o$@ -L $< 196 197$(obj)/%.lex.c: $(src)/%.l FORCE 198 $(call if_changed,flex) 199 200# YACC 201# --------------------------------------------------------------------------- 202quiet_cmd_bison = YACC $@ 203 cmd_bison = $(YACC) -o$@ -t -l $< 204 205$(obj)/%.tab.c: $(src)/%.y FORCE 206 $(call if_changed,bison) 207 208quiet_cmd_bison_h = YACC $@ 209 cmd_bison_h = $(YACC) -o/dev/null --defines=$@ -t -l $< 210 211$(obj)/%.tab.h: $(src)/%.y FORCE 212 $(call if_changed,bison_h) 213 214# Shipped files 215# =========================================================================== 216 217quiet_cmd_shipped = SHIPPED $@ 218cmd_shipped = cat $< > $@ 219 220$(obj)/%: $(src)/%_shipped 221 $(call cmd,shipped) 222 223# Commands useful for building a boot image 224# =========================================================================== 225# 226# Use as following: 227# 228# target: source(s) FORCE 229# $(if_changed,ld/objcopy/gzip) 230# 231# and add target to extra-y so that we know we have to 232# read in the saved command line 233 234# Linking 235# --------------------------------------------------------------------------- 236 237quiet_cmd_ld = LD $@ 238 cmd_ld = $(LD) $(ld_flags) $(real-prereqs) -o $@ 239 240# Archive 241# --------------------------------------------------------------------------- 242 243quiet_cmd_ar = AR $@ 244 cmd_ar = rm -f $@; $(AR) rcsTP$(KBUILD_ARFLAGS) $@ $(real-prereqs) 245 246# Objcopy 247# --------------------------------------------------------------------------- 248 249quiet_cmd_objcopy = OBJCOPY $@ 250cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $(OBJCOPYFLAGS_$(@F)) $< $@ 251 252# Gzip 253# --------------------------------------------------------------------------- 254 255quiet_cmd_gzip = GZIP $@ 256 cmd_gzip = cat $(real-prereqs) | gzip -n -f -9 > $@ 257 258# DTC 259# --------------------------------------------------------------------------- 260DTC ?= $(objtree)/scripts/dtc/dtc 261 262# Disable noisy checks by default 263ifeq ($(findstring 1,$(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),) 264DTC_FLAGS += -Wno-unit_address_vs_reg \ 265 -Wno-unit_address_format \ 266 -Wno-avoid_unnecessary_addr_size \ 267 -Wno-alias_paths \ 268 -Wno-graph_child_address \ 269 -Wno-simple_bus_reg \ 270 -Wno-unique_unit_address \ 271 -Wno-pci_device_reg 272endif 273 274ifneq ($(findstring 2,$(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),) 275DTC_FLAGS += -Wnode_name_chars_strict \ 276 -Wproperty_name_chars_strict 277endif 278 279DTC_FLAGS += $(DTC_FLAGS_$(basetarget)) 280 281# Generate an assembly file to wrap the output of the device tree compiler 282quiet_cmd_dt_S_dtb= DTB $@ 283cmd_dt_S_dtb= \ 284{ \ 285 echo '\#include <asm-generic/vmlinux.lds.h>'; \ 286 echo '.section .dtb.init.rodata,"a"'; \ 287 echo '.balign STRUCT_ALIGNMENT'; \ 288 echo '.global __dtb_$(subst -,_,$(*F))_begin'; \ 289 echo '__dtb_$(subst -,_,$(*F))_begin:'; \ 290 echo '.incbin "$<" '; \ 291 echo '__dtb_$(subst -,_,$(*F))_end:'; \ 292 echo '.global __dtb_$(subst -,_,$(*F))_end'; \ 293 echo '.balign STRUCT_ALIGNMENT'; \ 294} > $@ 295 296$(obj)/%.dtb.S: $(obj)/%.dtb FORCE 297 $(call if_changed,dt_S_dtb) 298 299quiet_cmd_dtc = DTC $@ 300cmd_dtc = mkdir -p $(dir ${dtc-tmp}) ; \ 301 $(HOSTCC) -E $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $< ; \ 302 $(DTC) -O $(2) -o $@ -b 0 \ 303 $(addprefix -i,$(dir $<) $(DTC_INCLUDE)) $(DTC_FLAGS) \ 304 -d $(depfile).dtc.tmp $(dtc-tmp) ; \ 305 cat $(depfile).pre.tmp $(depfile).dtc.tmp > $(depfile) 306 307$(obj)/%.dtb: $(src)/%.dts $(DTC) FORCE 308 $(call if_changed_dep,dtc,dtb) 309 310DT_CHECKER ?= dt-validate 311DT_BINDING_DIR := Documentation/devicetree/bindings 312DT_TMP_SCHEMA := $(objtree)/$(DT_BINDING_DIR)/processed-schema.yaml 313 314quiet_cmd_dtb_check = CHECK $@ 315 cmd_dtb_check = $(DT_CHECKER) -u $(srctree)/$(DT_BINDING_DIR) -p $(DT_TMP_SCHEMA) $@ ; 316 317define rule_dtc_dt_yaml 318 $(call cmd_and_fixdep,dtc,yaml) 319 $(call cmd,dtb_check) 320endef 321 322$(obj)/%.dt.yaml: $(src)/%.dts $(DTC) $(DT_TMP_SCHEMA) FORCE 323 $(call if_changed_rule,dtc_dt_yaml) 324 325dtc-tmp = $(subst $(comma),_,$(dot-target).dts.tmp) 326 327# Bzip2 328# --------------------------------------------------------------------------- 329 330# Bzip2 and LZMA do not include size in file... so we have to fake that; 331# append the size as a 32-bit littleendian number as gzip does. 332size_append = printf $(shell \ 333dec_size=0; \ 334for F in $(real-prereqs); do \ 335 fsize=$$($(CONFIG_SHELL) $(srctree)/scripts/file-size.sh $$F); \ 336 dec_size=$$(expr $$dec_size + $$fsize); \ 337done; \ 338printf "%08x\n" $$dec_size | \ 339 sed 's/\(..\)/\1 /g' | { \ 340 read ch0 ch1 ch2 ch3; \ 341 for ch in $$ch3 $$ch2 $$ch1 $$ch0; do \ 342 printf '%s%03o' '\\' $$((0x$$ch)); \ 343 done; \ 344 } \ 345) 346 347quiet_cmd_bzip2 = BZIP2 $@ 348 cmd_bzip2 = { cat $(real-prereqs) | bzip2 -9; $(size_append); } > $@ 349 350# Lzma 351# --------------------------------------------------------------------------- 352 353quiet_cmd_lzma = LZMA $@ 354 cmd_lzma = { cat $(real-prereqs) | lzma -9; $(size_append); } > $@ 355 356quiet_cmd_lzo = LZO $@ 357 cmd_lzo = { cat $(real-prereqs) | lzop -9; $(size_append); } > $@ 358 359quiet_cmd_lz4 = LZ4 $@ 360 cmd_lz4 = { cat $(real-prereqs) | lz4c -l -c1 stdin stdout; \ 361 $(size_append); } > $@ 362 363# U-Boot mkimage 364# --------------------------------------------------------------------------- 365 366MKIMAGE := $(srctree)/scripts/mkuboot.sh 367 368# SRCARCH just happens to match slightly more than ARCH (on sparc), so reduces 369# the number of overrides in arch makefiles 370UIMAGE_ARCH ?= $(SRCARCH) 371UIMAGE_COMPRESSION ?= $(if $(2),$(2),none) 372UIMAGE_OPTS-y ?= 373UIMAGE_TYPE ?= kernel 374UIMAGE_LOADADDR ?= arch_must_set_this 375UIMAGE_ENTRYADDR ?= $(UIMAGE_LOADADDR) 376UIMAGE_NAME ?= 'Linux-$(KERNELRELEASE)' 377 378quiet_cmd_uimage = UIMAGE $@ 379 cmd_uimage = $(CONFIG_SHELL) $(MKIMAGE) -A $(UIMAGE_ARCH) -O linux \ 380 -C $(UIMAGE_COMPRESSION) $(UIMAGE_OPTS-y) \ 381 -T $(UIMAGE_TYPE) \ 382 -a $(UIMAGE_LOADADDR) -e $(UIMAGE_ENTRYADDR) \ 383 -n $(UIMAGE_NAME) -d $< $@ 384 385# XZ 386# --------------------------------------------------------------------------- 387# Use xzkern to compress the kernel image and xzmisc to compress other things. 388# 389# xzkern uses a big LZMA2 dictionary since it doesn't increase memory usage 390# of the kernel decompressor. A BCJ filter is used if it is available for 391# the target architecture. xzkern also appends uncompressed size of the data 392# using size_append. The .xz format has the size information available at 393# the end of the file too, but it's in more complex format and it's good to 394# avoid changing the part of the boot code that reads the uncompressed size. 395# Note that the bytes added by size_append will make the xz tool think that 396# the file is corrupt. This is expected. 397# 398# xzmisc doesn't use size_append, so it can be used to create normal .xz 399# files. xzmisc uses smaller LZMA2 dictionary than xzkern, because a very 400# big dictionary would increase the memory usage too much in the multi-call 401# decompression mode. A BCJ filter isn't used either. 402quiet_cmd_xzkern = XZKERN $@ 403 cmd_xzkern = { cat $(real-prereqs) | sh $(srctree)/scripts/xz_wrap.sh; \ 404 $(size_append); } > $@ 405 406quiet_cmd_xzmisc = XZMISC $@ 407 cmd_xzmisc = cat $(real-prereqs) | xz --check=crc32 --lzma2=dict=1MiB > $@ 408 409# ASM offsets 410# --------------------------------------------------------------------------- 411 412# Default sed regexp - multiline due to syntax constraints 413# 414# Use [:space:] because LLVM's integrated assembler inserts <tab> around 415# the .ascii directive whereas GCC keeps the <space> as-is. 416define sed-offsets 417 's:^[[:space:]]*\.ascii[[:space:]]*"\(.*\)".*:\1:; \ 418 /^->/{s:->#\(.*\):/* \1 */:; \ 419 s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \ 420 s:->::; p;}' 421endef 422 423# Use filechk to avoid rebuilds when a header changes, but the resulting file 424# does not 425define filechk_offsets 426 echo "#ifndef $2"; \ 427 echo "#define $2"; \ 428 echo "/*"; \ 429 echo " * DO NOT MODIFY."; \ 430 echo " *"; \ 431 echo " * This file was generated by Kbuild"; \ 432 echo " */"; \ 433 echo ""; \ 434 sed -ne $(sed-offsets) < $<; \ 435 echo ""; \ 436 echo "#endif" 437endef 438