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.o 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.o, $(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# Build list of the parts of our composite objects, our composite 51# objects depend on those (obviously) 52multi-objs-y := $(foreach m, $(multi-used-y), $($(m:.o=-objs)) $($(m:.o=-y))) 53multi-objs-m := $(foreach m, $(multi-used-m), $($(m:.o=-objs)) $($(m:.o=-y))) 54 55# $(subdir-obj-y) is the list of objects in $(obj-y) which uses dir/ to 56# tell kbuild to descend 57subdir-obj-y := $(filter %/built-in.o, $(obj-y)) 58 59# Replace multi-part objects by their individual parts, look at local dir only 60real-objs-y := $(foreach m, $(filter-out $(subdir-obj-y), $(obj-y)), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))),$($(m:.o=-objs)) $($(m:.o=-y)),$(m))) 61real-objs-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))) 62 63# DTB 64# If CONFIG_OF_ALL_DTBS is enabled, all DT blobs are built 65extra-y += $(dtb-y) 66extra-$(CONFIG_OF_ALL_DTBS) += $(dtb-) 67 68# Add subdir path 69 70extra-y := $(addprefix $(obj)/,$(extra-y)) 71always := $(addprefix $(obj)/,$(always)) 72targets := $(addprefix $(obj)/,$(targets)) 73modorder := $(addprefix $(obj)/,$(modorder)) 74obj-y := $(addprefix $(obj)/,$(obj-y)) 75obj-m := $(addprefix $(obj)/,$(obj-m)) 76lib-y := $(addprefix $(obj)/,$(lib-y)) 77subdir-obj-y := $(addprefix $(obj)/,$(subdir-obj-y)) 78real-objs-y := $(addprefix $(obj)/,$(real-objs-y)) 79real-objs-m := $(addprefix $(obj)/,$(real-objs-m)) 80single-used-m := $(addprefix $(obj)/,$(single-used-m)) 81multi-used-y := $(addprefix $(obj)/,$(multi-used-y)) 82multi-used-m := $(addprefix $(obj)/,$(multi-used-m)) 83multi-objs-y := $(addprefix $(obj)/,$(multi-objs-y)) 84multi-objs-m := $(addprefix $(obj)/,$(multi-objs-m)) 85subdir-ym := $(addprefix $(obj)/,$(subdir-ym)) 86 87# These flags are needed for modversions and compiling, so we define them here 88# $(modname_flags) defines KBUILD_MODNAME as the name of the module it will 89# end up in (or would, if it gets compiled in) 90# Note: Files that end up in two or more modules are compiled without the 91# KBUILD_MODNAME definition. The reason is that any made-up name would 92# differ in different configs. 93name-fix = $(squote)$(quote)$(subst $(comma),_,$(subst -,_,$1))$(quote)$(squote) 94basename_flags = -DKBUILD_BASENAME=$(call name-fix,$(basetarget)) 95modname_flags = $(if $(filter 1,$(words $(modname))),\ 96 -DKBUILD_MODNAME=$(call name-fix,$(modname))) 97 98orig_c_flags = $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) \ 99 $(ccflags-y) $(CFLAGS_$(basetarget).o) 100_c_flags = $(filter-out $(CFLAGS_REMOVE_$(basetarget).o), $(orig_c_flags)) 101orig_a_flags = $(KBUILD_CPPFLAGS) $(KBUILD_AFLAGS) \ 102 $(asflags-y) $(AFLAGS_$(basetarget).o) 103_a_flags = $(filter-out $(AFLAGS_REMOVE_$(basetarget).o), $(orig_a_flags)) 104_cpp_flags = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$(@F)) 105 106# 107# Enable gcov profiling flags for a file, directory or for all files depending 108# on variables GCOV_PROFILE_obj.o, GCOV_PROFILE and CONFIG_GCOV_PROFILE_ALL 109# (in this order) 110# 111ifeq ($(CONFIG_GCOV_KERNEL),y) 112_c_flags += $(if $(patsubst n%,, \ 113 $(GCOV_PROFILE_$(basetarget).o)$(GCOV_PROFILE)$(CONFIG_GCOV_PROFILE_ALL)), \ 114 $(CFLAGS_GCOV)) 115endif 116 117# 118# Enable address sanitizer flags for kernel except some files or directories 119# we don't want to check (depends on variables KASAN_SANITIZE_obj.o, KASAN_SANITIZE) 120# 121ifeq ($(CONFIG_KASAN),y) 122_c_flags += $(if $(patsubst n%,, \ 123 $(KASAN_SANITIZE_$(basetarget).o)$(KASAN_SANITIZE)y), \ 124 $(CFLAGS_KASAN), $(CFLAGS_KASAN_NOSANITIZE)) 125endif 126 127ifeq ($(CONFIG_UBSAN),y) 128_c_flags += $(if $(patsubst n%,, \ 129 $(UBSAN_SANITIZE_$(basetarget).o)$(UBSAN_SANITIZE)$(CONFIG_UBSAN_SANITIZE_ALL)), \ 130 $(CFLAGS_UBSAN)) 131endif 132 133ifeq ($(CONFIG_KCOV),y) 134_c_flags += $(if $(patsubst n%,, \ 135 $(KCOV_INSTRUMENT_$(basetarget).o)$(KCOV_INSTRUMENT)$(CONFIG_KCOV_INSTRUMENT_ALL)), \ 136 $(CFLAGS_KCOV)) 137endif 138 139# If building the kernel in a separate objtree expand all occurrences 140# of -Idir to -I$(srctree)/dir except for absolute paths (starting with '/'). 141 142ifeq ($(KBUILD_SRC),) 143__c_flags = $(_c_flags) 144__a_flags = $(_a_flags) 145__cpp_flags = $(_cpp_flags) 146else 147 148# -I$(obj) locates generated .h files 149# $(call addtree,-I$(obj)) locates .h files in srctree, from generated .c files 150# and locates generated .h files 151# FIXME: Replace both with specific CFLAGS* statements in the makefiles 152__c_flags = $(if $(obj),$(call addtree,-I$(src)) -I$(obj)) \ 153 $(call flags,_c_flags) 154__a_flags = $(call flags,_a_flags) 155__cpp_flags = $(call flags,_cpp_flags) 156endif 157 158c_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ 159 $(__c_flags) $(modkern_cflags) \ 160 $(basename_flags) $(modname_flags) 161 162a_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ 163 $(__a_flags) $(modkern_aflags) 164 165cpp_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ 166 $(__cpp_flags) 167 168ld_flags = $(LDFLAGS) $(ldflags-y) 169 170DTC_INCLUDE := $(srctree)/scripts/dtc/include-prefixes 171 172dtc_cpp_flags = -Wp,-MD,$(depfile).pre.tmp -nostdinc \ 173 $(addprefix -I,$(DTC_INCLUDE)) \ 174 -undef -D__DTS__ 175 176# Finds the multi-part object the current object will be linked into 177modname-multi = $(sort $(foreach m,$(multi-used),\ 178 $(if $(filter $(subst $(obj)/,,$*.o), $($(m:.o=-objs)) $($(m:.o=-y))),$(m:.o=)))) 179 180# Useful for describing the dependency of composite objects 181# Usage: 182# $(call multi_depend, multi_used_targets, suffix_to_remove, suffix_to_add) 183define multi_depend 184$(foreach m, $(notdir $1), \ 185 $(eval $(obj)/$m: \ 186 $(addprefix $(obj)/, $(foreach s, $3, $($(m:%$(strip $2)=%$(s))))))) 187endef 188 189# LEX 190# --------------------------------------------------------------------------- 191quiet_cmd_flex = LEX $@ 192 cmd_flex = $(LEX) -o$@ -L $< 193 194ifdef REGENERATE_PARSERS 195.PRECIOUS: $(src)/%.lex.c_shipped 196$(src)/%.lex.c_shipped: $(src)/%.l 197 $(call cmd,flex) 198endif 199 200.PRECIOUS: $(obj)/%.lex.c 201$(filter %.lex.c,$(targets)): $(obj)/%.lex.c: $(src)/%.l FORCE 202 $(call if_changed,flex) 203 204# YACC 205# --------------------------------------------------------------------------- 206quiet_cmd_bison = YACC $@ 207 cmd_bison = $(YACC) -o$@ -t -l $< 208 209ifdef REGENERATE_PARSERS 210.PRECIOUS: $(src)/%.tab.c_shipped 211$(src)/%.tab.c_shipped: $(src)/%.y 212 $(call cmd,bison) 213endif 214 215.PRECIOUS: $(obj)/%.tab.c 216$(filter %.tab.c,$(targets)): $(obj)/%.tab.c: $(src)/%.y FORCE 217 $(call if_changed,bison) 218 219quiet_cmd_bison_h = YACC $@ 220 cmd_bison_h = bison -o/dev/null --defines=$@ -t -l -p $(YACC_PREFIX) $< 221 222ifdef REGENERATE_PARSERS 223.PRECIOUS: $(src)/%.tab.h_shipped 224$(src)/%.tab.h_shipped: $(src)/%.y 225 $(call cmd,bison_h) 226endif 227 228.PRECIOUS: $(obj)/%.tab.h 229$(filter %.tab.h,$(targets)): $(obj)/%.tab.h: $(src)/%.y FORCE 230 $(call if_changed,bison_h) 231 232# Shipped files 233# =========================================================================== 234 235quiet_cmd_shipped = SHIPPED $@ 236cmd_shipped = cat $< > $@ 237 238$(obj)/%: $(src)/%_shipped 239 $(call cmd,shipped) 240 241# Commands useful for building a boot image 242# =========================================================================== 243# 244# Use as following: 245# 246# target: source(s) FORCE 247# $(if_changed,ld/objcopy/gzip) 248# 249# and add target to extra-y so that we know we have to 250# read in the saved command line 251 252# Linking 253# --------------------------------------------------------------------------- 254 255quiet_cmd_ld = LD $@ 256cmd_ld = $(LD) $(LDFLAGS) $(ldflags-y) $(LDFLAGS_$(@F)) \ 257 $(filter-out FORCE,$^) -o $@ 258 259# Objcopy 260# --------------------------------------------------------------------------- 261 262quiet_cmd_objcopy = OBJCOPY $@ 263cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $(OBJCOPYFLAGS_$(@F)) $< $@ 264 265# Gzip 266# --------------------------------------------------------------------------- 267 268quiet_cmd_gzip = GZIP $@ 269cmd_gzip = (cat $(filter-out FORCE,$^) | gzip -n -f -9 > $@) || \ 270 (rm -f $@ ; false) 271 272# DTC 273# --------------------------------------------------------------------------- 274DTC ?= $(objtree)/scripts/dtc/dtc 275 276# Disable noisy checks by default 277ifeq ($(findstring 1,$(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),) 278DTC_FLAGS += -Wno-unit_address_vs_reg \ 279 -Wno-simple_bus_reg \ 280 -Wno-unit_address_format \ 281 -Wno-pci_bridge \ 282 -Wno-pci_device_bus_num \ 283 -Wno-pci_device_reg 284endif 285 286ifneq ($(findstring 2,$(KBUILD_ENABLE_EXTRA_GCC_CHECKS)),) 287DTC_FLAGS += -Wnode_name_chars_strict \ 288 -Wproperty_name_chars_strict 289endif 290 291DTC_FLAGS += $(DTC_FLAGS_$(basetarget)) 292 293# Generate an assembly file to wrap the output of the device tree compiler 294quiet_cmd_dt_S_dtb= DTB $@ 295cmd_dt_S_dtb= \ 296( \ 297 echo '\#include <asm-generic/vmlinux.lds.h>'; \ 298 echo '.section .dtb.init.rodata,"a"'; \ 299 echo '.balign STRUCT_ALIGNMENT'; \ 300 echo '.global __dtb_$(*F)_begin'; \ 301 echo '__dtb_$(*F)_begin:'; \ 302 echo '.incbin "$<" '; \ 303 echo '__dtb_$(*F)_end:'; \ 304 echo '.global __dtb_$(*F)_end'; \ 305 echo '.balign STRUCT_ALIGNMENT'; \ 306) > $@ 307 308$(obj)/%.dtb.S: $(obj)/%.dtb 309 $(call cmd,dt_S_dtb) 310 311quiet_cmd_dtc = DTC $@ 312cmd_dtc = mkdir -p $(dir ${dtc-tmp}) ; \ 313 $(CPP) $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $< ; \ 314 $(DTC) -O dtb -o $@ -b 0 \ 315 $(addprefix -i,$(dir $<) $(DTC_INCLUDE)) $(DTC_FLAGS) \ 316 -d $(depfile).dtc.tmp $(dtc-tmp) ; \ 317 cat $(depfile).pre.tmp $(depfile).dtc.tmp > $(depfile) 318 319$(obj)/%.dtb: $(src)/%.dts FORCE 320 $(call if_changed_dep,dtc) 321 322dtc-tmp = $(subst $(comma),_,$(dot-target).dts.tmp) 323 324# Bzip2 325# --------------------------------------------------------------------------- 326 327# Bzip2 and LZMA do not include size in file... so we have to fake that; 328# append the size as a 32-bit littleendian number as gzip does. 329size_append = printf $(shell \ 330dec_size=0; \ 331for F in $1; do \ 332 fsize=$$(stat -c "%s" $$F); \ 333 dec_size=$$(expr $$dec_size + $$fsize); \ 334done; \ 335printf "%08x\n" $$dec_size | \ 336 sed 's/\(..\)/\1 /g' | { \ 337 read ch0 ch1 ch2 ch3; \ 338 for ch in $$ch3 $$ch2 $$ch1 $$ch0; do \ 339 printf '%s%03o' '\\' $$((0x$$ch)); \ 340 done; \ 341 } \ 342) 343 344quiet_cmd_bzip2 = BZIP2 $@ 345cmd_bzip2 = (cat $(filter-out FORCE,$^) | \ 346 bzip2 -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \ 347 (rm -f $@ ; false) 348 349# Lzma 350# --------------------------------------------------------------------------- 351 352quiet_cmd_lzma = LZMA $@ 353cmd_lzma = (cat $(filter-out FORCE,$^) | \ 354 lzma -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \ 355 (rm -f $@ ; false) 356 357quiet_cmd_lzo = LZO $@ 358cmd_lzo = (cat $(filter-out FORCE,$^) | \ 359 lzop -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \ 360 (rm -f $@ ; false) 361 362quiet_cmd_lz4 = LZ4 $@ 363cmd_lz4 = (cat $(filter-out FORCE,$^) | \ 364 lz4c -l -c1 stdin stdout && $(call size_append, $(filter-out FORCE,$^))) > $@ || \ 365 (rm -f $@ ; false) 366 367# U-Boot mkimage 368# --------------------------------------------------------------------------- 369 370MKIMAGE := $(srctree)/scripts/mkuboot.sh 371 372# SRCARCH just happens to match slightly more than ARCH (on sparc), so reduces 373# the number of overrides in arch makefiles 374UIMAGE_ARCH ?= $(SRCARCH) 375UIMAGE_COMPRESSION ?= $(if $(2),$(2),none) 376UIMAGE_OPTS-y ?= 377UIMAGE_TYPE ?= kernel 378UIMAGE_LOADADDR ?= arch_must_set_this 379UIMAGE_ENTRYADDR ?= $(UIMAGE_LOADADDR) 380UIMAGE_NAME ?= 'Linux-$(KERNELRELEASE)' 381UIMAGE_IN ?= $< 382UIMAGE_OUT ?= $@ 383 384quiet_cmd_uimage = UIMAGE $(UIMAGE_OUT) 385 cmd_uimage = $(CONFIG_SHELL) $(MKIMAGE) -A $(UIMAGE_ARCH) -O linux \ 386 -C $(UIMAGE_COMPRESSION) $(UIMAGE_OPTS-y) \ 387 -T $(UIMAGE_TYPE) \ 388 -a $(UIMAGE_LOADADDR) -e $(UIMAGE_ENTRYADDR) \ 389 -n $(UIMAGE_NAME) -d $(UIMAGE_IN) $(UIMAGE_OUT) 390 391# XZ 392# --------------------------------------------------------------------------- 393# Use xzkern to compress the kernel image and xzmisc to compress other things. 394# 395# xzkern uses a big LZMA2 dictionary since it doesn't increase memory usage 396# of the kernel decompressor. A BCJ filter is used if it is available for 397# the target architecture. xzkern also appends uncompressed size of the data 398# using size_append. The .xz format has the size information available at 399# the end of the file too, but it's in more complex format and it's good to 400# avoid changing the part of the boot code that reads the uncompressed size. 401# Note that the bytes added by size_append will make the xz tool think that 402# the file is corrupt. This is expected. 403# 404# xzmisc doesn't use size_append, so it can be used to create normal .xz 405# files. xzmisc uses smaller LZMA2 dictionary than xzkern, because a very 406# big dictionary would increase the memory usage too much in the multi-call 407# decompression mode. A BCJ filter isn't used either. 408quiet_cmd_xzkern = XZKERN $@ 409cmd_xzkern = (cat $(filter-out FORCE,$^) | \ 410 sh $(srctree)/scripts/xz_wrap.sh && \ 411 $(call size_append, $(filter-out FORCE,$^))) > $@ || \ 412 (rm -f $@ ; false) 413 414quiet_cmd_xzmisc = XZMISC $@ 415cmd_xzmisc = (cat $(filter-out FORCE,$^) | \ 416 xz --check=crc32 --lzma2=dict=1MiB) > $@ || \ 417 (rm -f $@ ; false) 418 419# ASM offsets 420# --------------------------------------------------------------------------- 421 422# Default sed regexp - multiline due to syntax constraints 423# 424# Use [:space:] because LLVM's integrated assembler inserts <tab> around 425# the .ascii directive whereas GCC keeps the <space> as-is. 426define sed-offsets 427 's:^[[:space:]]*\.ascii[[:space:]]*"\(.*\)".*:\1:; \ 428 /^->/{s:->#\(.*\):/* \1 */:; \ 429 s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \ 430 s:->::; p;}' 431endef 432 433# Use filechk to avoid rebuilds when a header changes, but the resulting file 434# does not 435define filechk_offsets 436 (set -e; \ 437 echo "#ifndef $2"; \ 438 echo "#define $2"; \ 439 echo "/*"; \ 440 echo " * DO NOT MODIFY."; \ 441 echo " *"; \ 442 echo " * This file was generated by Kbuild"; \ 443 echo " */"; \ 444 echo ""; \ 445 sed -ne $(sed-offsets); \ 446 echo ""; \ 447 echo "#endif" ) 448endef 449