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 # CPU-specific tuning. Anything which can be shared with UML should go here. 84 include arch/x86/Makefile_32.cpu 85 KBUILD_CFLAGS += $(cflags-y) 86 87 # temporary until string.h is fixed 88 KBUILD_CFLAGS += -ffreestanding 89else 90 BITS := 64 91 UTS_MACHINE := x86_64 92 CHECKFLAGS += -D__x86_64__ 93 94 biarch := -m64 95 KBUILD_AFLAGS += -m64 96 KBUILD_CFLAGS += -m64 97 98 # Align jump targets to 1 byte, not the default 16 bytes: 99 KBUILD_CFLAGS += $(call cc-option,-falign-jumps=1) 100 101 # Pack loops tightly as well: 102 KBUILD_CFLAGS += $(call cc-option,-falign-loops=1) 103 104 # Don't autogenerate traditional x87 instructions 105 KBUILD_CFLAGS += $(call cc-option,-mno-80387) 106 KBUILD_CFLAGS += $(call cc-option,-mno-fp-ret-in-387) 107 108 # By default gcc and clang use a stack alignment of 16 bytes for x86. 109 # However the standard kernel entry on x86-64 leaves the stack on an 110 # 8-byte boundary. If the compiler isn't informed about the actual 111 # alignment it will generate extra alignment instructions for the 112 # default alignment which keep the stack *mis*aligned. 113 # Furthermore an alignment to the register width reduces stack usage 114 # and the number of alignment instructions. 115 KBUILD_CFLAGS += $(call cc-option,$(cc_stack_align8)) 116 117 # Use -mskip-rax-setup if supported. 118 KBUILD_CFLAGS += $(call cc-option,-mskip-rax-setup) 119 120 # FIXME - should be integrated in Makefile.cpu (Makefile_32.cpu) 121 cflags-$(CONFIG_MK8) += $(call cc-option,-march=k8) 122 cflags-$(CONFIG_MPSC) += $(call cc-option,-march=nocona) 123 124 cflags-$(CONFIG_MCORE2) += \ 125 $(call cc-option,-march=core2,$(call cc-option,-mtune=generic)) 126 cflags-$(CONFIG_MATOM) += $(call cc-option,-march=atom) \ 127 $(call cc-option,-mtune=atom,$(call cc-option,-mtune=generic)) 128 cflags-$(CONFIG_GENERIC_CPU) += $(call cc-option,-mtune=generic) 129 KBUILD_CFLAGS += $(cflags-y) 130 131 KBUILD_CFLAGS += -mno-red-zone 132 KBUILD_CFLAGS += -mcmodel=kernel 133 134 # -funit-at-a-time shrinks the kernel .text considerably 135 # unfortunately it makes reading oopses harder. 136 KBUILD_CFLAGS += $(call cc-option,-funit-at-a-time) 137endif 138 139ifdef CONFIG_X86_X32 140 x32_ld_ok := $(call try-run,\ 141 /bin/echo -e '1: .quad 1b' | \ 142 $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" - && \ 143 $(OBJCOPY) -O elf32-x86-64 "$$TMP" "$$TMPO" && \ 144 $(LD) -m elf32_x86_64 "$$TMPO" -o "$$TMP",y,n) 145 ifeq ($(x32_ld_ok),y) 146 CONFIG_X86_X32_ABI := y 147 KBUILD_AFLAGS += -DCONFIG_X86_X32_ABI 148 KBUILD_CFLAGS += -DCONFIG_X86_X32_ABI 149 else 150 $(warning CONFIG_X86_X32 enabled but no binutils support) 151 endif 152endif 153export CONFIG_X86_X32_ABI 154 155# 156# If the function graph tracer is used with mcount instead of fentry, 157# '-maccumulate-outgoing-args' is needed to prevent a GCC bug 158# (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=42109) 159# 160ifdef CONFIG_FUNCTION_GRAPH_TRACER 161 ifndef CONFIG_HAVE_FENTRY 162 ACCUMULATE_OUTGOING_ARGS := 1 163 else 164 ifeq ($(call cc-option-yn, -mfentry), n) 165 ACCUMULATE_OUTGOING_ARGS := 1 166 167 # GCC ignores '-maccumulate-outgoing-args' when used with '-Os'. 168 # If '-Os' is enabled, disable it and print a warning. 169 ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE 170 undefine CONFIG_CC_OPTIMIZE_FOR_SIZE 171 $(warning Disabling CONFIG_CC_OPTIMIZE_FOR_SIZE. Your compiler does not have -mfentry so you cannot optimize for size with CONFIG_FUNCTION_GRAPH_TRACER.) 172 endif 173 174 endif 175 endif 176endif 177 178ifndef CC_HAVE_ASM_GOTO 179 $(error Compiler lacks asm-goto support.) 180endif 181 182# 183# Jump labels need '-maccumulate-outgoing-args' for gcc < 4.5.2 to prevent a 184# GCC bug (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=46226). There's no way 185# to test for this bug at compile-time because the test case needs to execute, 186# which is a no-go for cross compilers. So check the GCC version instead. 187# 188ifdef CONFIG_JUMP_LABEL 189 ifneq ($(ACCUMULATE_OUTGOING_ARGS), 1) 190 ACCUMULATE_OUTGOING_ARGS = $(call cc-if-fullversion, -lt, 040502, 1) 191 endif 192endif 193 194ifeq ($(ACCUMULATE_OUTGOING_ARGS), 1) 195 # This compiler flag is not supported by Clang: 196 KBUILD_CFLAGS += $(call cc-option,-maccumulate-outgoing-args,) 197endif 198 199# Stackpointer is addressed different for 32 bit and 64 bit x86 200sp-$(CONFIG_X86_32) := esp 201sp-$(CONFIG_X86_64) := rsp 202 203# do binutils support CFI? 204cfi := $(call as-instr,.cfi_startproc\n.cfi_rel_offset $(sp-y)$(comma)0\n.cfi_endproc,-DCONFIG_AS_CFI=1) 205# is .cfi_signal_frame supported too? 206cfi-sigframe := $(call as-instr,.cfi_startproc\n.cfi_signal_frame\n.cfi_endproc,-DCONFIG_AS_CFI_SIGNAL_FRAME=1) 207cfi-sections := $(call as-instr,.cfi_sections .debug_frame,-DCONFIG_AS_CFI_SECTIONS=1) 208 209# does binutils support specific instructions? 210asinstr := $(call as-instr,fxsaveq (%rax),-DCONFIG_AS_FXSAVEQ=1) 211asinstr += $(call as-instr,pshufb %xmm0$(comma)%xmm0,-DCONFIG_AS_SSSE3=1) 212asinstr += $(call as-instr,crc32l %eax$(comma)%eax,-DCONFIG_AS_CRC32=1) 213avx_instr := $(call as-instr,vxorps %ymm0$(comma)%ymm1$(comma)%ymm2,-DCONFIG_AS_AVX=1) 214avx2_instr :=$(call as-instr,vpbroadcastb %xmm0$(comma)%ymm1,-DCONFIG_AS_AVX2=1) 215avx512_instr :=$(call as-instr,vpmovm2b %k1$(comma)%zmm5,-DCONFIG_AS_AVX512=1) 216sha1_ni_instr :=$(call as-instr,sha1msg1 %xmm0$(comma)%xmm1,-DCONFIG_AS_SHA1_NI=1) 217sha256_ni_instr :=$(call as-instr,sha256msg1 %xmm0$(comma)%xmm1,-DCONFIG_AS_SHA256_NI=1) 218 219KBUILD_AFLAGS += $(cfi) $(cfi-sigframe) $(cfi-sections) $(asinstr) $(avx_instr) $(avx2_instr) $(avx512_instr) $(sha1_ni_instr) $(sha256_ni_instr) 220KBUILD_CFLAGS += $(cfi) $(cfi-sigframe) $(cfi-sections) $(asinstr) $(avx_instr) $(avx2_instr) $(avx512_instr) $(sha1_ni_instr) $(sha256_ni_instr) 221 222KBUILD_LDFLAGS := -m elf_$(UTS_MACHINE) 223 224# 225# The 64-bit kernel must be aligned to 2MB. Pass -z max-page-size=0x200000 to 226# the linker to force 2MB page size regardless of the default page size used 227# by the linker. 228# 229ifdef CONFIG_X86_64 230KBUILD_LDFLAGS += $(call ld-option, -z max-page-size=0x200000) 231endif 232 233# Speed up the build 234KBUILD_CFLAGS += -pipe 235# Workaround for a gcc prelease that unfortunately was shipped in a suse release 236KBUILD_CFLAGS += -Wno-sign-compare 237# 238KBUILD_CFLAGS += -fno-asynchronous-unwind-tables 239 240# Avoid indirect branches in kernel to deal with Spectre 241ifdef CONFIG_RETPOLINE 242ifneq ($(RETPOLINE_CFLAGS),) 243 KBUILD_CFLAGS += $(RETPOLINE_CFLAGS) -DRETPOLINE 244endif 245endif 246 247archscripts: scripts_basic 248 $(Q)$(MAKE) $(build)=arch/x86/tools relocs 249 250### 251# Syscall table generation 252 253archheaders: 254 $(Q)$(MAKE) $(build)=arch/x86/entry/syscalls all 255 256### 257# Kernel objects 258 259head-y := arch/x86/kernel/head_$(BITS).o 260head-y += arch/x86/kernel/head$(BITS).o 261head-y += arch/x86/kernel/ebda.o 262head-y += arch/x86/kernel/platform-quirks.o 263 264libs-y += arch/x86/lib/ 265 266# See arch/x86/Kbuild for content of core part of the kernel 267core-y += arch/x86/ 268 269# drivers-y are linked after core-y 270drivers-$(CONFIG_MATH_EMULATION) += arch/x86/math-emu/ 271drivers-$(CONFIG_PCI) += arch/x86/pci/ 272 273# must be linked after kernel/ 274drivers-$(CONFIG_OPROFILE) += arch/x86/oprofile/ 275 276# suspend and hibernation support 277drivers-$(CONFIG_PM) += arch/x86/power/ 278 279drivers-$(CONFIG_FB) += arch/x86/video/ 280 281#### 282# boot loader support. Several targets are kept for legacy purposes 283 284boot := arch/x86/boot 285 286BOOT_TARGETS = bzlilo bzdisk fdimage fdimage144 fdimage288 isoimage 287 288PHONY += bzImage $(BOOT_TARGETS) 289 290# Default kernel to build 291all: bzImage 292 293# KBUILD_IMAGE specify target image being built 294KBUILD_IMAGE := $(boot)/bzImage 295 296bzImage: vmlinux 297ifeq ($(CONFIG_X86_DECODER_SELFTEST),y) 298 $(Q)$(MAKE) $(build)=arch/x86/tools posttest 299endif 300 $(Q)$(MAKE) $(build)=$(boot) $(KBUILD_IMAGE) 301 $(Q)mkdir -p $(objtree)/arch/$(UTS_MACHINE)/boot 302 $(Q)ln -fsn ../../x86/boot/bzImage $(objtree)/arch/$(UTS_MACHINE)/boot/$@ 303 304$(BOOT_TARGETS): vmlinux 305 $(Q)$(MAKE) $(build)=$(boot) $@ 306 307PHONY += install 308install: 309 $(Q)$(MAKE) $(build)=$(boot) $@ 310 311PHONY += vdso_install 312vdso_install: 313 $(Q)$(MAKE) $(build)=arch/x86/entry/vdso $@ 314 315archclean: 316 $(Q)rm -rf $(objtree)/arch/i386 317 $(Q)rm -rf $(objtree)/arch/x86_64 318 $(Q)$(MAKE) $(clean)=$(boot) 319 $(Q)$(MAKE) $(clean)=arch/x86/tools 320 321define archhelp 322 echo '* bzImage - Compressed kernel image (arch/x86/boot/bzImage)' 323 echo ' install - Install kernel using' 324 echo ' (your) ~/bin/$(INSTALLKERNEL) or' 325 echo ' (distribution) /sbin/$(INSTALLKERNEL) or' 326 echo ' install to $$(INSTALL_PATH) and run lilo' 327 echo ' fdimage - Create 1.4MB boot floppy image (arch/x86/boot/fdimage)' 328 echo ' fdimage144 - Create 1.4MB boot floppy image (arch/x86/boot/fdimage)' 329 echo ' fdimage288 - Create 2.8MB boot floppy image (arch/x86/boot/fdimage)' 330 echo ' isoimage - Create a boot CD-ROM image (arch/x86/boot/image.iso)' 331 echo ' bzdisk/fdimage*/isoimage also accept:' 332 echo ' FDARGS="..." arguments for the booted kernel' 333 echo ' FDINITRD=file initrd for the booted kernel' 334endef 335