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