1# SPDX-License-Identifier: GPL-2.0 2# Unified Makefile for i386 and x86_64 3 4# select defconfig based on actual architecture 5ifeq ($(ARCH),x86) 6 ifeq ($(shell uname -m),x86_64) 7 KBUILD_DEFCONFIG := x86_64_defconfig 8 else 9 KBUILD_DEFCONFIG := i386_defconfig 10 endif 11else 12 KBUILD_DEFCONFIG := $(ARCH)_defconfig 13endif 14 15# For gcc stack alignment is specified with -mpreferred-stack-boundary, 16# clang has the option -mstack-alignment for that purpose. 17ifneq ($(call cc-option, -mpreferred-stack-boundary=4),) 18 cc_stack_align4 := -mpreferred-stack-boundary=2 19 cc_stack_align8 := -mpreferred-stack-boundary=3 20else ifneq ($(call cc-option, -mstack-alignment=16),) 21 cc_stack_align4 := -mstack-alignment=4 22 cc_stack_align8 := -mstack-alignment=8 23endif 24 25# How to compile the 16-bit code. Note we always compile for -march=i386; 26# that way we can complain to the user if the CPU is insufficient. 27# 28# The -m16 option is supported by GCC >= 4.9 and clang >= 3.5. For 29# older versions of GCC, include an *assembly* header to make sure that 30# gcc doesn't play any games behind our back. 31CODE16GCC_CFLAGS := -m32 -Wa,$(srctree)/arch/x86/boot/code16gcc.h 32M16_CFLAGS := $(call cc-option, -m16, $(CODE16GCC_CFLAGS)) 33 34REALMODE_CFLAGS := $(M16_CFLAGS) -g -Os -DDISABLE_BRANCH_PROFILING \ 35 -Wall -Wstrict-prototypes -march=i386 -mregparm=3 \ 36 -fno-strict-aliasing -fomit-frame-pointer -fno-pic \ 37 -mno-mmx -mno-sse 38 39REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -ffreestanding) 40REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -fno-stack-protector) 41REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), $(cc_stack_align4)) 42export REALMODE_CFLAGS 43 44# BITS is used as extension for files which are available in a 32 bit 45# and a 64 bit version to simplify shared Makefiles. 46# e.g.: obj-y += foo_$(BITS).o 47export BITS 48 49ifdef CONFIG_X86_NEED_RELOCS 50 LDFLAGS_vmlinux := --emit-relocs 51endif 52 53# 54# Prevent GCC from generating any FP code by mistake. 55# 56# This must happen before we try the -mpreferred-stack-boundary, see: 57# 58# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53383 59# 60KBUILD_CFLAGS += -mno-sse -mno-mmx -mno-sse2 -mno-3dnow 61KBUILD_CFLAGS += $(call cc-option,-mno-avx,) 62 63ifeq ($(CONFIG_X86_32),y) 64 BITS := 32 65 UTS_MACHINE := i386 66 CHECKFLAGS += -D__i386__ 67 68 biarch := $(call cc-option,-m32) 69 KBUILD_AFLAGS += $(biarch) 70 KBUILD_CFLAGS += $(biarch) 71 72 KBUILD_CFLAGS += -msoft-float -mregparm=3 -freg-struct-return 73 74 # Never want PIC in a 32-bit kernel, prevent breakage with GCC built 75 # with nonstandard options 76 KBUILD_CFLAGS += -fno-pic 77 78 # Align the stack to the register width instead of using the default 79 # alignment of 16 bytes. This reduces stack usage and the number of 80 # alignment instructions. 81 KBUILD_CFLAGS += $(call cc-option,$(cc_stack_align4)) 82 83 # Disable unit-at-a-time mode on pre-gcc-4.0 compilers, it makes gcc use 84 # a lot more stack due to the lack of sharing of stacklots: 85 KBUILD_CFLAGS += $(call cc-ifversion, -lt, 0400, \ 86 $(call cc-option,-fno-unit-at-a-time)) 87 88 # CPU-specific tuning. Anything which can be shared with UML should go here. 89 include arch/x86/Makefile_32.cpu 90 KBUILD_CFLAGS += $(cflags-y) 91 92 # temporary until string.h is fixed 93 KBUILD_CFLAGS += -ffreestanding 94else 95 BITS := 64 96 UTS_MACHINE := x86_64 97 CHECKFLAGS += -D__x86_64__ -m64 98 99 biarch := -m64 100 KBUILD_AFLAGS += -m64 101 KBUILD_CFLAGS += -m64 102 103 # Align jump targets to 1 byte, not the default 16 bytes: 104 KBUILD_CFLAGS += $(call cc-option,-falign-jumps=1) 105 106 # Pack loops tightly as well: 107 KBUILD_CFLAGS += $(call cc-option,-falign-loops=1) 108 109 # Don't autogenerate traditional x87 instructions 110 KBUILD_CFLAGS += $(call cc-option,-mno-80387) 111 KBUILD_CFLAGS += $(call cc-option,-mno-fp-ret-in-387) 112 113 # By default gcc and clang use a stack alignment of 16 bytes for x86. 114 # However the standard kernel entry on x86-64 leaves the stack on an 115 # 8-byte boundary. If the compiler isn't informed about the actual 116 # alignment it will generate extra alignment instructions for the 117 # default alignment which keep the stack *mis*aligned. 118 # Furthermore an alignment to the register width reduces stack usage 119 # and the number of alignment instructions. 120 KBUILD_CFLAGS += $(call cc-option,$(cc_stack_align8)) 121 122 # Use -mskip-rax-setup if supported. 123 KBUILD_CFLAGS += $(call cc-option,-mskip-rax-setup) 124 125 # FIXME - should be integrated in Makefile.cpu (Makefile_32.cpu) 126 cflags-$(CONFIG_MK8) += $(call cc-option,-march=k8) 127 cflags-$(CONFIG_MPSC) += $(call cc-option,-march=nocona) 128 129 cflags-$(CONFIG_MCORE2) += \ 130 $(call cc-option,-march=core2,$(call cc-option,-mtune=generic)) 131 cflags-$(CONFIG_MATOM) += $(call cc-option,-march=atom) \ 132 $(call cc-option,-mtune=atom,$(call cc-option,-mtune=generic)) 133 cflags-$(CONFIG_GENERIC_CPU) += $(call cc-option,-mtune=generic) 134 KBUILD_CFLAGS += $(cflags-y) 135 136 KBUILD_CFLAGS += -mno-red-zone 137 KBUILD_CFLAGS += -mcmodel=kernel 138 139 # -funit-at-a-time shrinks the kernel .text considerably 140 # unfortunately it makes reading oopses harder. 141 KBUILD_CFLAGS += $(call cc-option,-funit-at-a-time) 142endif 143 144ifdef CONFIG_X86_X32 145 x32_ld_ok := $(call try-run,\ 146 /bin/echo -e '1: .quad 1b' | \ 147 $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" - && \ 148 $(OBJCOPY) -O elf32-x86-64 "$$TMP" "$$TMPO" && \ 149 $(LD) -m elf32_x86_64 "$$TMPO" -o "$$TMP",y,n) 150 ifeq ($(x32_ld_ok),y) 151 CONFIG_X86_X32_ABI := y 152 KBUILD_AFLAGS += -DCONFIG_X86_X32_ABI 153 KBUILD_CFLAGS += -DCONFIG_X86_X32_ABI 154 else 155 $(warning CONFIG_X86_X32 enabled but no binutils support) 156 endif 157endif 158export CONFIG_X86_X32_ABI 159 160# 161# If the function graph tracer is used with mcount instead of fentry, 162# '-maccumulate-outgoing-args' is needed to prevent a GCC bug 163# (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=42109) 164# 165ifdef CONFIG_FUNCTION_GRAPH_TRACER 166 ifndef CONFIG_HAVE_FENTRY 167 ACCUMULATE_OUTGOING_ARGS := 1 168 else 169 ifeq ($(call cc-option-yn, -mfentry), n) 170 ACCUMULATE_OUTGOING_ARGS := 1 171 172 # GCC ignores '-maccumulate-outgoing-args' when used with '-Os'. 173 # If '-Os' is enabled, disable it and print a warning. 174 ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE 175 undefine CONFIG_CC_OPTIMIZE_FOR_SIZE 176 $(warning Disabling CONFIG_CC_OPTIMIZE_FOR_SIZE. Your compiler does not have -mfentry so you cannot optimize for size with CONFIG_FUNCTION_GRAPH_TRACER.) 177 endif 178 179 endif 180 endif 181endif 182 183ifndef CC_HAVE_ASM_GOTO 184 $(error Compiler lacks asm-goto support.) 185endif 186 187# 188# Jump labels need '-maccumulate-outgoing-args' for gcc < 4.5.2 to prevent a 189# GCC bug (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=46226). There's no way 190# to test for this bug at compile-time because the test case needs to execute, 191# which is a no-go for cross compilers. So check the GCC version instead. 192# 193ifdef CONFIG_JUMP_LABEL 194 ifneq ($(ACCUMULATE_OUTGOING_ARGS), 1) 195 ACCUMULATE_OUTGOING_ARGS = $(call cc-if-fullversion, -lt, 040502, 1) 196 endif 197endif 198 199ifeq ($(ACCUMULATE_OUTGOING_ARGS), 1) 200 # This compiler flag is not supported by Clang: 201 KBUILD_CFLAGS += $(call cc-option,-maccumulate-outgoing-args,) 202endif 203 204# Stackpointer is addressed different for 32 bit and 64 bit x86 205sp-$(CONFIG_X86_32) := esp 206sp-$(CONFIG_X86_64) := rsp 207 208# do binutils support CFI? 209cfi := $(call as-instr,.cfi_startproc\n.cfi_rel_offset $(sp-y)$(comma)0\n.cfi_endproc,-DCONFIG_AS_CFI=1) 210# is .cfi_signal_frame supported too? 211cfi-sigframe := $(call as-instr,.cfi_startproc\n.cfi_signal_frame\n.cfi_endproc,-DCONFIG_AS_CFI_SIGNAL_FRAME=1) 212cfi-sections := $(call as-instr,.cfi_sections .debug_frame,-DCONFIG_AS_CFI_SECTIONS=1) 213 214# does binutils support specific instructions? 215asinstr := $(call as-instr,fxsaveq (%rax),-DCONFIG_AS_FXSAVEQ=1) 216asinstr += $(call as-instr,pshufb %xmm0$(comma)%xmm0,-DCONFIG_AS_SSSE3=1) 217asinstr += $(call as-instr,crc32l %eax$(comma)%eax,-DCONFIG_AS_CRC32=1) 218avx_instr := $(call as-instr,vxorps %ymm0$(comma)%ymm1$(comma)%ymm2,-DCONFIG_AS_AVX=1) 219avx2_instr :=$(call as-instr,vpbroadcastb %xmm0$(comma)%ymm1,-DCONFIG_AS_AVX2=1) 220avx512_instr :=$(call as-instr,vpmovm2b %k1$(comma)%zmm5,-DCONFIG_AS_AVX512=1) 221sha1_ni_instr :=$(call as-instr,sha1msg1 %xmm0$(comma)%xmm1,-DCONFIG_AS_SHA1_NI=1) 222sha256_ni_instr :=$(call as-instr,sha256msg1 %xmm0$(comma)%xmm1,-DCONFIG_AS_SHA256_NI=1) 223 224KBUILD_AFLAGS += $(cfi) $(cfi-sigframe) $(cfi-sections) $(asinstr) $(avx_instr) $(avx2_instr) $(avx512_instr) $(sha1_ni_instr) $(sha256_ni_instr) 225KBUILD_CFLAGS += $(cfi) $(cfi-sigframe) $(cfi-sections) $(asinstr) $(avx_instr) $(avx2_instr) $(avx512_instr) $(sha1_ni_instr) $(sha256_ni_instr) 226 227LDFLAGS := -m elf_$(UTS_MACHINE) 228 229# 230# The 64-bit kernel must be aligned to 2MB. Pass -z max-page-size=0x200000 to 231# the linker to force 2MB page size regardless of the default page size used 232# by the linker. 233# 234ifdef CONFIG_X86_64 235LDFLAGS += $(call ld-option, -z max-page-size=0x200000) 236endif 237 238# Speed up the build 239KBUILD_CFLAGS += -pipe 240# Workaround for a gcc prelease that unfortunately was shipped in a suse release 241KBUILD_CFLAGS += -Wno-sign-compare 242# 243KBUILD_CFLAGS += -fno-asynchronous-unwind-tables 244 245# Avoid indirect branches in kernel to deal with Spectre 246ifdef CONFIG_RETPOLINE 247ifneq ($(RETPOLINE_CFLAGS),) 248 KBUILD_CFLAGS += $(RETPOLINE_CFLAGS) -DRETPOLINE 249endif 250endif 251 252archscripts: scripts_basic 253 $(Q)$(MAKE) $(build)=arch/x86/tools relocs 254 255### 256# Syscall table generation 257 258archheaders: 259 $(Q)$(MAKE) $(build)=arch/x86/entry/syscalls all 260 261archprepare: 262ifeq ($(CONFIG_KEXEC_FILE),y) 263 $(Q)$(MAKE) $(build)=arch/x86/purgatory arch/x86/purgatory/kexec-purgatory.c 264endif 265 266### 267# Kernel objects 268 269head-y := arch/x86/kernel/head_$(BITS).o 270head-y += arch/x86/kernel/head$(BITS).o 271head-y += arch/x86/kernel/ebda.o 272head-y += arch/x86/kernel/platform-quirks.o 273 274libs-y += arch/x86/lib/ 275 276# See arch/x86/Kbuild for content of core part of the kernel 277core-y += arch/x86/ 278 279# drivers-y are linked after core-y 280drivers-$(CONFIG_MATH_EMULATION) += arch/x86/math-emu/ 281drivers-$(CONFIG_PCI) += arch/x86/pci/ 282 283# must be linked after kernel/ 284drivers-$(CONFIG_OPROFILE) += arch/x86/oprofile/ 285 286# suspend and hibernation support 287drivers-$(CONFIG_PM) += arch/x86/power/ 288 289drivers-$(CONFIG_FB) += arch/x86/video/ 290 291#### 292# boot loader support. Several targets are kept for legacy purposes 293 294boot := arch/x86/boot 295 296BOOT_TARGETS = bzlilo bzdisk fdimage fdimage144 fdimage288 isoimage 297 298PHONY += bzImage $(BOOT_TARGETS) 299 300# Default kernel to build 301all: bzImage 302 303# KBUILD_IMAGE specify target image being built 304KBUILD_IMAGE := $(boot)/bzImage 305 306bzImage: vmlinux 307ifeq ($(CONFIG_X86_DECODER_SELFTEST),y) 308 $(Q)$(MAKE) $(build)=arch/x86/tools posttest 309endif 310 $(Q)$(MAKE) $(build)=$(boot) $(KBUILD_IMAGE) 311 $(Q)mkdir -p $(objtree)/arch/$(UTS_MACHINE)/boot 312 $(Q)ln -fsn ../../x86/boot/bzImage $(objtree)/arch/$(UTS_MACHINE)/boot/$@ 313 314$(BOOT_TARGETS): vmlinux 315 $(Q)$(MAKE) $(build)=$(boot) $@ 316 317PHONY += install 318install: 319 $(Q)$(MAKE) $(build)=$(boot) $@ 320 321PHONY += vdso_install 322vdso_install: 323 $(Q)$(MAKE) $(build)=arch/x86/entry/vdso $@ 324 325archclean: 326 $(Q)rm -rf $(objtree)/arch/i386 327 $(Q)rm -rf $(objtree)/arch/x86_64 328 $(Q)$(MAKE) $(clean)=$(boot) 329 $(Q)$(MAKE) $(clean)=arch/x86/tools 330 $(Q)$(MAKE) $(clean)=arch/x86/purgatory 331 332define archhelp 333 echo '* bzImage - Compressed kernel image (arch/x86/boot/bzImage)' 334 echo ' install - Install kernel using' 335 echo ' (your) ~/bin/$(INSTALLKERNEL) or' 336 echo ' (distribution) /sbin/$(INSTALLKERNEL) or' 337 echo ' install to $$(INSTALL_PATH) and run lilo' 338 echo ' fdimage - Create 1.4MB boot floppy image (arch/x86/boot/fdimage)' 339 echo ' fdimage144 - Create 1.4MB boot floppy image (arch/x86/boot/fdimage)' 340 echo ' fdimage288 - Create 2.8MB boot floppy image (arch/x86/boot/fdimage)' 341 echo ' isoimage - Create a boot CD-ROM image (arch/x86/boot/image.iso)' 342 echo ' bzdisk/fdimage*/isoimage also accept:' 343 echo ' FDARGS="..." arguments for the booted kernel' 344 echo ' FDINITRD=file initrd for the booted kernel' 345endef 346