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# 9# flags that take effect in sub directories 10export KBUILD_SUBDIR_ASFLAGS := $(KBUILD_SUBDIR_ASFLAGS) $(subdir-asflags-y) 11export KBUILD_SUBDIR_CCFLAGS := $(KBUILD_SUBDIR_CCFLAGS) $(subdir-ccflags-y) 12 13# Figure out what we need to build from the various variables 14# =========================================================================== 15 16# When an object is listed to be built compiled-in and modular, 17# only build the compiled-in version 18 19obj-m := $(filter-out $(obj-y),$(obj-m)) 20 21# Libraries are always collected in one lib file. 22# Filter out objects already built-in 23 24lib-y := $(filter-out $(obj-y), $(sort $(lib-y) $(lib-m))) 25 26 27# Handle objects in subdirs 28# --------------------------------------------------------------------------- 29# o if we encounter foo/ in $(obj-y), replace it by foo/built-in.o 30# and add the directory to the list of dirs to descend into: $(subdir-y) 31# o if we encounter foo/ in $(obj-m), remove it from $(obj-m) 32# and add the directory to the list of dirs to descend into: $(subdir-m) 33 34# Determine modorder. 35# Unfortunately, we don't have information about ordering between -y 36# and -m subdirs. Just put -y's first. 37modorder := $(patsubst %/,%/modules.order, $(filter %/, $(obj-y)) $(obj-m:.o=.ko)) 38 39__subdir-y := $(patsubst %/,%,$(filter %/, $(obj-y))) 40subdir-y += $(__subdir-y) 41__subdir-m := $(patsubst %/,%,$(filter %/, $(obj-m))) 42subdir-m += $(__subdir-m) 43obj-y := $(patsubst %/, %/built-in.o, $(obj-y)) 44obj-m := $(filter-out %/, $(obj-m)) 45 46# Subdirectories we need to descend into 47 48subdir-ym := $(sort $(subdir-y) $(subdir-m)) 49 50# if $(foo-objs) exists, foo.o is a composite object 51multi-used-y := $(sort $(foreach m,$(obj-y), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y))), $(m)))) 52multi-used-m := $(sort $(foreach m,$(obj-m), $(if $(strip $($(m:.o=-objs)) $($(m:.o=-y)) $($(m:.o=-m))), $(m)))) 53multi-used := $(multi-used-y) $(multi-used-m) 54single-used-m := $(sort $(filter-out $(multi-used-m),$(obj-m))) 55 56# Build list of the parts of our composite objects, our composite 57# objects depend on those (obviously) 58multi-objs-y := $(foreach m, $(multi-used-y), $($(m:.o=-objs)) $($(m:.o=-y))) 59multi-objs-m := $(foreach m, $(multi-used-m), $($(m:.o=-objs)) $($(m:.o=-y))) 60multi-objs := $(multi-objs-y) $(multi-objs-m) 61 62# $(subdir-obj-y) is the list of objects in $(obj-y) which uses dir/ to 63# tell kbuild to descend 64subdir-obj-y := $(filter %/built-in.o, $(obj-y)) 65 66# $(obj-dirs) is a list of directories that contain object files 67obj-dirs := $(dir $(multi-objs) $(obj-y)) 68 69# Replace multi-part objects by their individual parts, look at local dir only 70real-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))) $(extra-y) 71real-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))) 72 73# DTB 74# If CONFIG_OF_ALL_DTBS is enabled, all DT blobs are built 75extra-y += $(dtb-y) 76extra-$(CONFIG_OF_ALL_DTBS) += $(dtb-) 77 78# Add subdir path 79 80extra-y := $(addprefix $(obj)/,$(extra-y)) 81always := $(addprefix $(obj)/,$(always)) 82targets := $(addprefix $(obj)/,$(targets)) 83modorder := $(addprefix $(obj)/,$(modorder)) 84obj-y := $(addprefix $(obj)/,$(obj-y)) 85obj-m := $(addprefix $(obj)/,$(obj-m)) 86lib-y := $(addprefix $(obj)/,$(lib-y)) 87subdir-obj-y := $(addprefix $(obj)/,$(subdir-obj-y)) 88real-objs-y := $(addprefix $(obj)/,$(real-objs-y)) 89real-objs-m := $(addprefix $(obj)/,$(real-objs-m)) 90single-used-m := $(addprefix $(obj)/,$(single-used-m)) 91multi-used-y := $(addprefix $(obj)/,$(multi-used-y)) 92multi-used-m := $(addprefix $(obj)/,$(multi-used-m)) 93multi-objs-y := $(addprefix $(obj)/,$(multi-objs-y)) 94multi-objs-m := $(addprefix $(obj)/,$(multi-objs-m)) 95subdir-ym := $(addprefix $(obj)/,$(subdir-ym)) 96obj-dirs := $(addprefix $(obj)/,$(obj-dirs)) 97 98# These flags are needed for modversions and compiling, so we define them here 99# already 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) 102# Note: Files that end up in two or more modules are compiled without the 103# KBUILD_MODNAME definition. The reason is that any made-up name would 104# differ in different configs. 105name-fix = $(squote)$(quote)$(subst $(comma),_,$(subst -,_,$1))$(quote)$(squote) 106basename_flags = -DKBUILD_BASENAME=$(call name-fix,$(basetarget)) 107modname_flags = $(if $(filter 1,$(words $(modname))),\ 108 -DKBUILD_MODNAME=$(call name-fix,$(modname))) 109 110orig_c_flags = $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(KBUILD_SUBDIR_CCFLAGS) \ 111 $(ccflags-y) $(CFLAGS_$(basetarget).o) 112_c_flags = $(filter-out $(CFLAGS_REMOVE_$(basetarget).o), $(orig_c_flags)) 113orig_a_flags = $(KBUILD_CPPFLAGS) $(KBUILD_AFLAGS) $(KBUILD_SUBDIR_ASFLAGS) \ 114 $(asflags-y) $(AFLAGS_$(basetarget).o) 115_a_flags = $(filter-out $(AFLAGS_REMOVE_$(basetarget).o), $(orig_a_flags)) 116_cpp_flags = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$(@F)) 117 118# 119# Enable gcov profiling flags for a file, directory or for all files depending 120# on variables GCOV_PROFILE_obj.o, GCOV_PROFILE and CONFIG_GCOV_PROFILE_ALL 121# (in this order) 122# 123ifeq ($(CONFIG_GCOV_KERNEL),y) 124_c_flags += $(if $(patsubst n%,, \ 125 $(GCOV_PROFILE_$(basetarget).o)$(GCOV_PROFILE)$(CONFIG_GCOV_PROFILE_ALL)), \ 126 $(CFLAGS_GCOV)) 127endif 128 129# 130# Enable address sanitizer flags for kernel except some files or directories 131# we don't want to check (depends on variables KASAN_SANITIZE_obj.o, KASAN_SANITIZE) 132# 133ifeq ($(CONFIG_KASAN),y) 134_c_flags += $(if $(patsubst n%,, \ 135 $(KASAN_SANITIZE_$(basetarget).o)$(KASAN_SANITIZE)y), \ 136 $(CFLAGS_KASAN)) 137endif 138 139ifeq ($(CONFIG_UBSAN),y) 140_c_flags += $(if $(patsubst n%,, \ 141 $(UBSAN_SANITIZE_$(basetarget).o)$(UBSAN_SANITIZE)$(CONFIG_UBSAN_SANITIZE_ALL)), \ 142 $(CFLAGS_UBSAN)) 143endif 144 145ifeq ($(CONFIG_KCOV),y) 146_c_flags += $(if $(patsubst n%,, \ 147 $(KCOV_INSTRUMENT_$(basetarget).o)$(KCOV_INSTRUMENT)$(CONFIG_KCOV_INSTRUMENT_ALL)), \ 148 $(CFLAGS_KCOV)) 149endif 150 151# If building the kernel in a separate objtree expand all occurrences 152# of -Idir to -I$(srctree)/dir except for absolute paths (starting with '/'). 153 154ifeq ($(KBUILD_SRC),) 155__c_flags = $(_c_flags) 156__a_flags = $(_a_flags) 157__cpp_flags = $(_cpp_flags) 158else 159 160# -I$(obj) locates generated .h files 161# $(call addtree,-I$(obj)) locates .h files in srctree, from generated .c files 162# and locates generated .h files 163# FIXME: Replace both with specific CFLAGS* statements in the makefiles 164__c_flags = $(if $(obj),$(call addtree,-I$(src)) -I$(obj)) \ 165 $(call flags,_c_flags) 166__a_flags = $(call flags,_a_flags) 167__cpp_flags = $(call flags,_cpp_flags) 168endif 169 170c_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ 171 $(__c_flags) $(modkern_cflags) \ 172 $(basename_flags) $(modname_flags) 173 174a_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ 175 $(__a_flags) $(modkern_aflags) 176 177cpp_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ 178 $(__cpp_flags) 179 180ld_flags = $(LDFLAGS) $(ldflags-y) 181 182DTC_INCLUDE := $(srctree)/scripts/dtc/include-prefixes 183 184dtc_cpp_flags = -Wp,-MD,$(depfile).pre.tmp -nostdinc \ 185 $(addprefix -I,$(DTC_INCLUDE)) \ 186 -undef -D__DTS__ 187 188# Finds the multi-part object the current object will be linked into 189modname-multi = $(sort $(foreach m,$(multi-used),\ 190 $(if $(filter $(subst $(obj)/,,$*.o), $($(m:.o=-objs)) $($(m:.o=-y))),$(m:.o=)))) 191 192# Useful for describing the dependency of composite objects 193# Usage: 194# $(call multi_depend, multi_used_targets, suffix_to_remove, suffix_to_add) 195define multi_depend 196$(foreach m, $(notdir $1), \ 197 $(eval $(obj)/$m: \ 198 $(addprefix $(obj)/, $(foreach s, $3, $($(m:%$(strip $2)=%$(s))))))) 199endef 200 201ifdef REGENERATE_PARSERS 202 203# LEX 204# --------------------------------------------------------------------------- 205LEX_PREFIX = $(if $(LEX_PREFIX_${baseprereq}),$(LEX_PREFIX_${baseprereq}),yy) 206 207quiet_cmd_flex = LEX $@ 208 cmd_flex = flex -o$@ -L -P $(LEX_PREFIX) $< 209 210.PRECIOUS: $(src)/%.lex.c_shipped 211$(src)/%.lex.c_shipped: $(src)/%.l 212 $(call cmd,flex) 213 214# YACC 215# --------------------------------------------------------------------------- 216YACC_PREFIX = $(if $(YACC_PREFIX_${baseprereq}),$(YACC_PREFIX_${baseprereq}),yy) 217 218quiet_cmd_bison = YACC $@ 219 cmd_bison = bison -o$@ -t -l -p $(YACC_PREFIX) $< 220 221.PRECIOUS: $(src)/%.tab.c_shipped 222$(src)/%.tab.c_shipped: $(src)/%.y 223 $(call cmd,bison) 224 225quiet_cmd_bison_h = YACC $@ 226 cmd_bison_h = bison -o/dev/null --defines=$@ -t -l -p $(YACC_PREFIX) $< 227 228.PRECIOUS: $(src)/%.tab.h_shipped 229$(src)/%.tab.h_shipped: $(src)/%.y 230 $(call cmd,bison_h) 231 232endif 233 234# Shipped files 235# =========================================================================== 236 237quiet_cmd_shipped = SHIPPED $@ 238cmd_shipped = cat $< > $@ 239 240$(obj)/%: $(src)/%_shipped 241 $(call cmd,shipped) 242 243# Commands useful for building a boot image 244# =========================================================================== 245# 246# Use as following: 247# 248# target: source(s) FORCE 249# $(if_changed,ld/objcopy/gzip) 250# 251# and add target to extra-y so that we know we have to 252# read in the saved command line 253 254# Linking 255# --------------------------------------------------------------------------- 256 257quiet_cmd_ld = LD $@ 258cmd_ld = $(LD) $(LDFLAGS) $(ldflags-y) $(LDFLAGS_$(@F)) \ 259 $(filter-out FORCE,$^) -o $@ 260 261# Objcopy 262# --------------------------------------------------------------------------- 263 264quiet_cmd_objcopy = OBJCOPY $@ 265cmd_objcopy = $(OBJCOPY) $(OBJCOPYFLAGS) $(OBJCOPYFLAGS_$(@F)) $< $@ 266 267# Gzip 268# --------------------------------------------------------------------------- 269 270quiet_cmd_gzip = GZIP $@ 271cmd_gzip = (cat $(filter-out FORCE,$^) | gzip -n -f -9 > $@) || \ 272 (rm -f $@ ; false) 273 274# DTC 275# --------------------------------------------------------------------------- 276DTC ?= $(objtree)/scripts/dtc/dtc 277 278# Disable noisy checks by default 279ifeq ($(KBUILD_ENABLE_EXTRA_GCC_CHECKS),) 280DTC_FLAGS += -Wno-unit_address_vs_reg \ 281 -Wno-simple_bus_reg \ 282 -Wno-unit_address_format \ 283 -Wno-pci_bridge \ 284 -Wno-pci_device_bus_num \ 285 -Wno-pci_device_reg 286endif 287 288ifeq ($(KBUILD_ENABLE_EXTRA_GCC_CHECKS),2) 289DTC_FLAGS += -Wnode_name_chars_strict \ 290 -Wproperty_name_chars_strict 291endif 292 293DTC_FLAGS += $(DTC_FLAGS_$(basetarget)) 294 295# Generate an assembly file to wrap the output of the device tree compiler 296quiet_cmd_dt_S_dtb= DTB $@ 297cmd_dt_S_dtb= \ 298( \ 299 echo '\#include <asm-generic/vmlinux.lds.h>'; \ 300 echo '.section .dtb.init.rodata,"a"'; \ 301 echo '.balign STRUCT_ALIGNMENT'; \ 302 echo '.global __dtb_$(*F)_begin'; \ 303 echo '__dtb_$(*F)_begin:'; \ 304 echo '.incbin "$<" '; \ 305 echo '__dtb_$(*F)_end:'; \ 306 echo '.global __dtb_$(*F)_end'; \ 307 echo '.balign STRUCT_ALIGNMENT'; \ 308) > $@ 309 310$(obj)/%.dtb.S: $(obj)/%.dtb 311 $(call cmd,dt_S_dtb) 312 313quiet_cmd_dtc = DTC $@ 314cmd_dtc = mkdir -p $(dir ${dtc-tmp}) ; \ 315 $(CPP) $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $< ; \ 316 $(DTC) -O dtb -o $@ -b 0 \ 317 $(addprefix -i,$(dir $<) $(DTC_INCLUDE)) $(DTC_FLAGS) \ 318 -d $(depfile).dtc.tmp $(dtc-tmp) ; \ 319 cat $(depfile).pre.tmp $(depfile).dtc.tmp > $(depfile) 320 321$(obj)/%.dtb: $(src)/%.dts FORCE 322 $(call if_changed_dep,dtc) 323 324dtc-tmp = $(subst $(comma),_,$(dot-target).dts.tmp) 325 326# Bzip2 327# --------------------------------------------------------------------------- 328 329# Bzip2 and LZMA do not include size in file... so we have to fake that; 330# append the size as a 32-bit littleendian number as gzip does. 331size_append = printf $(shell \ 332dec_size=0; \ 333for F in $1; do \ 334 fsize=$$(stat -c "%s" $$F); \ 335 dec_size=$$(expr $$dec_size + $$fsize); \ 336done; \ 337printf "%08x\n" $$dec_size | \ 338 sed 's/\(..\)/\1 /g' | { \ 339 read ch0 ch1 ch2 ch3; \ 340 for ch in $$ch3 $$ch2 $$ch1 $$ch0; do \ 341 printf '%s%03o' '\\' $$((0x$$ch)); \ 342 done; \ 343 } \ 344) 345 346quiet_cmd_bzip2 = BZIP2 $@ 347cmd_bzip2 = (cat $(filter-out FORCE,$^) | \ 348 bzip2 -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \ 349 (rm -f $@ ; false) 350 351# Lzma 352# --------------------------------------------------------------------------- 353 354quiet_cmd_lzma = LZMA $@ 355cmd_lzma = (cat $(filter-out FORCE,$^) | \ 356 lzma -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \ 357 (rm -f $@ ; false) 358 359quiet_cmd_lzo = LZO $@ 360cmd_lzo = (cat $(filter-out FORCE,$^) | \ 361 lzop -9 && $(call size_append, $(filter-out FORCE,$^))) > $@ || \ 362 (rm -f $@ ; false) 363 364quiet_cmd_lz4 = LZ4 $@ 365cmd_lz4 = (cat $(filter-out FORCE,$^) | \ 366 lz4c -l -c1 stdin stdout && $(call size_append, $(filter-out FORCE,$^))) > $@ || \ 367 (rm -f $@ ; false) 368 369# U-Boot mkimage 370# --------------------------------------------------------------------------- 371 372MKIMAGE := $(srctree)/scripts/mkuboot.sh 373 374# SRCARCH just happens to match slightly more than ARCH (on sparc), so reduces 375# the number of overrides in arch makefiles 376UIMAGE_ARCH ?= $(SRCARCH) 377UIMAGE_COMPRESSION ?= $(if $(2),$(2),none) 378UIMAGE_OPTS-y ?= 379UIMAGE_TYPE ?= kernel 380UIMAGE_LOADADDR ?= arch_must_set_this 381UIMAGE_ENTRYADDR ?= $(UIMAGE_LOADADDR) 382UIMAGE_NAME ?= 'Linux-$(KERNELRELEASE)' 383UIMAGE_IN ?= $< 384UIMAGE_OUT ?= $@ 385 386quiet_cmd_uimage = UIMAGE $(UIMAGE_OUT) 387 cmd_uimage = $(CONFIG_SHELL) $(MKIMAGE) -A $(UIMAGE_ARCH) -O linux \ 388 -C $(UIMAGE_COMPRESSION) $(UIMAGE_OPTS-y) \ 389 -T $(UIMAGE_TYPE) \ 390 -a $(UIMAGE_LOADADDR) -e $(UIMAGE_ENTRYADDR) \ 391 -n $(UIMAGE_NAME) -d $(UIMAGE_IN) $(UIMAGE_OUT) 392 393# XZ 394# --------------------------------------------------------------------------- 395# Use xzkern to compress the kernel image and xzmisc to compress other things. 396# 397# xzkern uses a big LZMA2 dictionary since it doesn't increase memory usage 398# of the kernel decompressor. A BCJ filter is used if it is available for 399# the target architecture. xzkern also appends uncompressed size of the data 400# using size_append. The .xz format has the size information available at 401# the end of the file too, but it's in more complex format and it's good to 402# avoid changing the part of the boot code that reads the uncompressed size. 403# Note that the bytes added by size_append will make the xz tool think that 404# the file is corrupt. This is expected. 405# 406# xzmisc doesn't use size_append, so it can be used to create normal .xz 407# files. xzmisc uses smaller LZMA2 dictionary than xzkern, because a very 408# big dictionary would increase the memory usage too much in the multi-call 409# decompression mode. A BCJ filter isn't used either. 410quiet_cmd_xzkern = XZKERN $@ 411cmd_xzkern = (cat $(filter-out FORCE,$^) | \ 412 sh $(srctree)/scripts/xz_wrap.sh && \ 413 $(call size_append, $(filter-out FORCE,$^))) > $@ || \ 414 (rm -f $@ ; false) 415 416quiet_cmd_xzmisc = XZMISC $@ 417cmd_xzmisc = (cat $(filter-out FORCE,$^) | \ 418 xz --check=crc32 --lzma2=dict=1MiB) > $@ || \ 419 (rm -f $@ ; false) 420 421# ASM offsets 422# --------------------------------------------------------------------------- 423 424# Default sed regexp - multiline due to syntax constraints 425# 426# Use [:space:] because LLVM's integrated assembler inserts <tab> around 427# the .ascii directive whereas GCC keeps the <space> as-is. 428define sed-offsets 429 's:^[[:space:]]*\.ascii[[:space:]]*"\(.*\)".*:\1:; \ 430 /^->/{s:->#\(.*\):/* \1 */:; \ 431 s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \ 432 s:->::; p;}' 433endef 434 435# Use filechk to avoid rebuilds when a header changes, but the resulting file 436# does not 437define filechk_offsets 438 (set -e; \ 439 echo "#ifndef $2"; \ 440 echo "#define $2"; \ 441 echo "/*"; \ 442 echo " * DO NOT MODIFY."; \ 443 echo " *"; \ 444 echo " * This file was generated by Kbuild"; \ 445 echo " */"; \ 446 echo ""; \ 447 sed -ne $(sed-offsets); \ 448 echo ""; \ 449 echo "#endif" ) 450endef 451