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