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