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), $(foo-m), or $(foo-) exists, foo.o is a composite object 45multi-used-y := $(sort $(foreach m,$(obj-y), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-))), $(m)))) 46multi-used-m := $(sort $(foreach m,$(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m)) $($(m:.o=-))), $(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=-))),$($(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=-))),$($(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# target with $(obj)/ and its suffix stripped 105target-stem = $(basename $(patsubst $(obj)/%,%,$@)) 106 107# These flags are needed for modversions and compiling, so we define them here 108# $(modname_flags) defines KBUILD_MODNAME as the name of the module it will 109# end up in (or would, if it gets compiled in) 110name-fix = $(squote)$(quote)$(subst $(comma),_,$(subst -,_,$1))$(quote)$(squote) 111basename_flags = -DKBUILD_BASENAME=$(call name-fix,$(basetarget)) 112modname_flags = -DKBUILD_MODNAME=$(call name-fix,$(modname)) 113 114orig_c_flags = $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) \ 115 $(ccflags-y) $(CFLAGS_$(target-stem).o) 116_c_flags = $(filter-out $(CFLAGS_REMOVE_$(target-stem).o), $(orig_c_flags)) 117orig_a_flags = $(KBUILD_CPPFLAGS) $(KBUILD_AFLAGS) \ 118 $(asflags-y) $(AFLAGS_$(target-stem).o) 119_a_flags = $(filter-out $(AFLAGS_REMOVE_$(target-stem).o), $(orig_a_flags)) 120_cpp_flags = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$(target-stem).lds) 121 122# 123# Enable gcov profiling flags for a file, directory or for all files depending 124# on variables GCOV_PROFILE_obj.o, GCOV_PROFILE and CONFIG_GCOV_PROFILE_ALL 125# (in this order) 126# 127ifeq ($(CONFIG_GCOV_KERNEL),y) 128_c_flags += $(if $(patsubst n%,, \ 129 $(GCOV_PROFILE_$(basetarget).o)$(GCOV_PROFILE)$(CONFIG_GCOV_PROFILE_ALL)), \ 130 $(CFLAGS_GCOV)) 131endif 132 133# 134# Enable address sanitizer flags for kernel except some files or directories 135# we don't want to check (depends on variables KASAN_SANITIZE_obj.o, KASAN_SANITIZE) 136# 137ifeq ($(CONFIG_KASAN),y) 138_c_flags += $(if $(patsubst n%,, \ 139 $(KASAN_SANITIZE_$(basetarget).o)$(KASAN_SANITIZE)y), \ 140 $(CFLAGS_KASAN), $(CFLAGS_KASAN_NOSANITIZE)) 141endif 142 143ifeq ($(CONFIG_UBSAN),y) 144_c_flags += $(if $(patsubst n%,, \ 145 $(UBSAN_SANITIZE_$(basetarget).o)$(UBSAN_SANITIZE)$(CONFIG_UBSAN_SANITIZE_ALL)), \ 146 $(CFLAGS_UBSAN)) 147endif 148 149ifeq ($(CONFIG_KCOV),y) 150_c_flags += $(if $(patsubst n%,, \ 151 $(KCOV_INSTRUMENT_$(basetarget).o)$(KCOV_INSTRUMENT)$(CONFIG_KCOV_INSTRUMENT_ALL)), \ 152 $(CFLAGS_KCOV)) 153endif 154 155# $(srctree)/$(src) for including checkin headers from generated source files 156# $(objtree)/$(obj) for including generated headers from checkin source files 157ifeq ($(KBUILD_EXTMOD),) 158ifdef building_out_of_srctree 159_c_flags += -I $(srctree)/$(src) -I $(objtree)/$(obj) 160_a_flags += -I $(srctree)/$(src) -I $(objtree)/$(obj) 161_cpp_flags += -I $(srctree)/$(src) -I $(objtree)/$(obj) 162endif 163endif 164 165part-of-module = $(if $(filter $(basename $@).o, $(real-obj-m)),y) 166quiet_modtag = $(if $(part-of-module),[M], ) 167 168modkern_cflags = \ 169 $(if $(part-of-module), \ 170 $(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \ 171 $(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL)) 172 173modkern_aflags = $(if $(part-of-module), \ 174 $(KBUILD_AFLAGS_MODULE) $(AFLAGS_MODULE), \ 175 $(KBUILD_AFLAGS_KERNEL) $(AFLAGS_KERNEL)) 176 177c_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ 178 -include $(srctree)/include/linux/compiler_types.h \ 179 $(_c_flags) $(modkern_cflags) \ 180 $(basename_flags) $(modname_flags) 181 182a_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ 183 $(_a_flags) $(modkern_aflags) 184 185cpp_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ 186 $(_cpp_flags) 187 188ld_flags = $(KBUILD_LDFLAGS) $(ldflags-y) $(LDFLAGS_$(@F)) 189 190DTC_INCLUDE := $(srctree)/scripts/dtc/include-prefixes 191 192dtc_cpp_flags = -Wp,-MD,$(depfile).pre.tmp -nostdinc \ 193 $(addprefix -I,$(DTC_INCLUDE)) \ 194 -undef -D__DTS__ 195 196# Useful for describing the dependency of composite objects 197# Usage: 198# $(call multi_depend, multi_used_targets, suffix_to_remove, suffix_to_add) 199define multi_depend 200$(foreach m, $(notdir $1), \ 201 $(eval $(obj)/$m: \ 202 $(addprefix $(obj)/, $(foreach s, $3, $($(m:%$(strip $2)=%$(s))))))) 203endef 204 205# Shipped files 206# =========================================================================== 207 208quiet_cmd_shipped = SHIPPED $@ 209cmd_shipped = cat $< > $@ 210 211$(obj)/%: $(src)/%_shipped 212 $(call cmd,shipped) 213 214# Commands useful for building a boot image 215# =========================================================================== 216# 217# Use as following: 218# 219# target: source(s) FORCE 220# $(if_changed,ld/objcopy/gzip) 221# 222# and add target to extra-y so that we know we have to 223# read in the saved command line 224 225# Linking 226# --------------------------------------------------------------------------- 227 228quiet_cmd_ld = LD $@ 229 cmd_ld = $(LD) $(ld_flags) $(real-prereqs) -o $@ 230 231# Archive 232# --------------------------------------------------------------------------- 233 234quiet_cmd_ar = AR $@ 235 cmd_ar = rm -f $@; $(AR) rcsTP$(KBUILD_ARFLAGS) $@ $(real-prereqs) 236 237# Objcopy 238# --------------------------------------------------------------------------- 239 240quiet_cmd_objcopy = OBJCOPY $@ 241cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $(OBJCOPYFLAGS_$(@F)) $< $@ 242 243# Gzip 244# --------------------------------------------------------------------------- 245 246quiet_cmd_gzip = GZIP $@ 247 cmd_gzip = cat $(real-prereqs) | gzip -n -f -9 > $@ 248 249# DTC 250# --------------------------------------------------------------------------- 251DTC ?= $(objtree)/scripts/dtc/dtc 252 253# Disable noisy checks by default 254ifeq ($(findstring 1,$(KBUILD_EXTRA_WARN)),) 255DTC_FLAGS += -Wno-unit_address_vs_reg \ 256 -Wno-unit_address_format \ 257 -Wno-avoid_unnecessary_addr_size \ 258 -Wno-alias_paths \ 259 -Wno-graph_child_address \ 260 -Wno-simple_bus_reg \ 261 -Wno-unique_unit_address \ 262 -Wno-pci_device_reg 263endif 264 265ifneq ($(findstring 2,$(KBUILD_EXTRA_WARN)),) 266DTC_FLAGS += -Wnode_name_chars_strict \ 267 -Wproperty_name_chars_strict 268endif 269 270DTC_FLAGS += $(DTC_FLAGS_$(basetarget)) 271 272# Generate an assembly file to wrap the output of the device tree compiler 273quiet_cmd_dt_S_dtb= DTB $@ 274cmd_dt_S_dtb= \ 275{ \ 276 echo '\#include <asm-generic/vmlinux.lds.h>'; \ 277 echo '.section .dtb.init.rodata,"a"'; \ 278 echo '.balign STRUCT_ALIGNMENT'; \ 279 echo '.global __dtb_$(subst -,_,$(*F))_begin'; \ 280 echo '__dtb_$(subst -,_,$(*F))_begin:'; \ 281 echo '.incbin "$<" '; \ 282 echo '__dtb_$(subst -,_,$(*F))_end:'; \ 283 echo '.global __dtb_$(subst -,_,$(*F))_end'; \ 284 echo '.balign STRUCT_ALIGNMENT'; \ 285} > $@ 286 287$(obj)/%.dtb.S: $(obj)/%.dtb FORCE 288 $(call if_changed,dt_S_dtb) 289 290quiet_cmd_dtc = DTC $@ 291cmd_dtc = mkdir -p $(dir ${dtc-tmp}) ; \ 292 $(HOSTCC) -E $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $< ; \ 293 $(DTC) -O $(2) -o $@ -b 0 \ 294 $(addprefix -i,$(dir $<) $(DTC_INCLUDE)) $(DTC_FLAGS) \ 295 -d $(depfile).dtc.tmp $(dtc-tmp) ; \ 296 cat $(depfile).pre.tmp $(depfile).dtc.tmp > $(depfile) 297 298$(obj)/%.dtb: $(src)/%.dts $(DTC) FORCE 299 $(call if_changed_dep,dtc,dtb) 300 301DT_CHECKER ?= dt-validate 302DT_BINDING_DIR := Documentation/devicetree/bindings 303DT_TMP_SCHEMA := $(objtree)/$(DT_BINDING_DIR)/processed-schema.yaml 304 305quiet_cmd_dtb_check = CHECK $@ 306 cmd_dtb_check = $(DT_CHECKER) -u $(srctree)/$(DT_BINDING_DIR) -p $(DT_TMP_SCHEMA) $@ ; 307 308define rule_dtc_dt_yaml 309 $(call cmd_and_fixdep,dtc,yaml) 310 $(call cmd,dtb_check) 311endef 312 313$(obj)/%.dt.yaml: $(src)/%.dts $(DTC) $(DT_TMP_SCHEMA) FORCE 314 $(call if_changed_rule,dtc_dt_yaml) 315 316dtc-tmp = $(subst $(comma),_,$(dot-target).dts.tmp) 317 318# Bzip2 319# --------------------------------------------------------------------------- 320 321# Bzip2 and LZMA do not include size in file... so we have to fake that; 322# append the size as a 32-bit littleendian number as gzip does. 323size_append = printf $(shell \ 324dec_size=0; \ 325for F in $(real-prereqs); do \ 326 fsize=$$($(CONFIG_SHELL) $(srctree)/scripts/file-size.sh $$F); \ 327 dec_size=$$(expr $$dec_size + $$fsize); \ 328done; \ 329printf "%08x\n" $$dec_size | \ 330 sed 's/\(..\)/\1 /g' | { \ 331 read ch0 ch1 ch2 ch3; \ 332 for ch in $$ch3 $$ch2 $$ch1 $$ch0; do \ 333 printf '%s%03o' '\\' $$((0x$$ch)); \ 334 done; \ 335 } \ 336) 337 338quiet_cmd_bzip2 = BZIP2 $@ 339 cmd_bzip2 = { cat $(real-prereqs) | bzip2 -9; $(size_append); } > $@ 340 341# Lzma 342# --------------------------------------------------------------------------- 343 344quiet_cmd_lzma = LZMA $@ 345 cmd_lzma = { cat $(real-prereqs) | lzma -9; $(size_append); } > $@ 346 347quiet_cmd_lzo = LZO $@ 348 cmd_lzo = { cat $(real-prereqs) | lzop -9; $(size_append); } > $@ 349 350quiet_cmd_lz4 = LZ4 $@ 351 cmd_lz4 = { cat $(real-prereqs) | lz4c -l -c1 stdin stdout; \ 352 $(size_append); } > $@ 353 354# U-Boot mkimage 355# --------------------------------------------------------------------------- 356 357MKIMAGE := $(srctree)/scripts/mkuboot.sh 358 359# SRCARCH just happens to match slightly more than ARCH (on sparc), so reduces 360# the number of overrides in arch makefiles 361UIMAGE_ARCH ?= $(SRCARCH) 362UIMAGE_COMPRESSION ?= $(if $(2),$(2),none) 363UIMAGE_OPTS-y ?= 364UIMAGE_TYPE ?= kernel 365UIMAGE_LOADADDR ?= arch_must_set_this 366UIMAGE_ENTRYADDR ?= $(UIMAGE_LOADADDR) 367UIMAGE_NAME ?= 'Linux-$(KERNELRELEASE)' 368 369quiet_cmd_uimage = UIMAGE $@ 370 cmd_uimage = $(BASH) $(MKIMAGE) -A $(UIMAGE_ARCH) -O linux \ 371 -C $(UIMAGE_COMPRESSION) $(UIMAGE_OPTS-y) \ 372 -T $(UIMAGE_TYPE) \ 373 -a $(UIMAGE_LOADADDR) -e $(UIMAGE_ENTRYADDR) \ 374 -n $(UIMAGE_NAME) -d $< $@ 375 376# XZ 377# --------------------------------------------------------------------------- 378# Use xzkern to compress the kernel image and xzmisc to compress other things. 379# 380# xzkern uses a big LZMA2 dictionary since it doesn't increase memory usage 381# of the kernel decompressor. A BCJ filter is used if it is available for 382# the target architecture. xzkern also appends uncompressed size of the data 383# using size_append. The .xz format has the size information available at 384# the end of the file too, but it's in more complex format and it's good to 385# avoid changing the part of the boot code that reads the uncompressed size. 386# Note that the bytes added by size_append will make the xz tool think that 387# the file is corrupt. This is expected. 388# 389# xzmisc doesn't use size_append, so it can be used to create normal .xz 390# files. xzmisc uses smaller LZMA2 dictionary than xzkern, because a very 391# big dictionary would increase the memory usage too much in the multi-call 392# decompression mode. A BCJ filter isn't used either. 393quiet_cmd_xzkern = XZKERN $@ 394 cmd_xzkern = { cat $(real-prereqs) | sh $(srctree)/scripts/xz_wrap.sh; \ 395 $(size_append); } > $@ 396 397quiet_cmd_xzmisc = XZMISC $@ 398 cmd_xzmisc = cat $(real-prereqs) | xz --check=crc32 --lzma2=dict=1MiB > $@ 399 400# ASM offsets 401# --------------------------------------------------------------------------- 402 403# Default sed regexp - multiline due to syntax constraints 404# 405# Use [:space:] because LLVM's integrated assembler inserts <tab> around 406# the .ascii directive whereas GCC keeps the <space> as-is. 407define sed-offsets 408 's:^[[:space:]]*\.ascii[[:space:]]*"\(.*\)".*:\1:; \ 409 /^->/{s:->#\(.*\):/* \1 */:; \ 410 s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \ 411 s:->::; p;}' 412endef 413 414# Use filechk to avoid rebuilds when a header changes, but the resulting file 415# does not 416define filechk_offsets 417 echo "#ifndef $2"; \ 418 echo "#define $2"; \ 419 echo "/*"; \ 420 echo " * DO NOT MODIFY."; \ 421 echo " *"; \ 422 echo " * This file was generated by Kbuild"; \ 423 echo " */"; \ 424 echo ""; \ 425 sed -ne $(sed-offsets) < $<; \ 426 echo ""; \ 427 echo "#endif" 428endef 429