1# Unified Makefile for i386 and x86_64 2 3# select defconfig based on actual architecture 4ifeq ($(ARCH),x86) 5 ifeq ($(shell uname -m),x86_64) 6 KBUILD_DEFCONFIG := x86_64_defconfig 7 else 8 KBUILD_DEFCONFIG := i386_defconfig 9 endif 10else 11 KBUILD_DEFCONFIG := $(ARCH)_defconfig 12endif 13 14# For gcc stack alignment is specified with -mpreferred-stack-boundary, 15# clang has the option -mstack-alignment for that purpose. 16ifneq ($(call cc-option, -mpreferred-stack-boundary=4),) 17 cc_stack_align4 := -mpreferred-stack-boundary=2 18 cc_stack_align8 := -mpreferred-stack-boundary=3 19else ifneq ($(call cc-option, -mstack-alignment=16),) 20 cc_stack_align4 := -mstack-alignment=4 21 cc_stack_align8 := -mstack-alignment=8 22endif 23 24# How to compile the 16-bit code. Note we always compile for -march=i386; 25# that way we can complain to the user if the CPU is insufficient. 26# 27# The -m16 option is supported by GCC >= 4.9 and clang >= 3.5. For 28# older versions of GCC, include an *assembly* header to make sure that 29# gcc doesn't play any games behind our back. 30CODE16GCC_CFLAGS := -m32 -Wa,$(srctree)/arch/x86/boot/code16gcc.h 31M16_CFLAGS := $(call cc-option, -m16, $(CODE16GCC_CFLAGS)) 32 33REALMODE_CFLAGS := $(M16_CFLAGS) -g -Os -D__KERNEL__ \ 34 -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 $(call cc-option,-fcf-protection=none) 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), -Wno-address-of-packed-member) 42REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), $(cc_stack_align4)) 43REALMODE_CFLAGS += $(CLANG_FLAGS) 44export REALMODE_CFLAGS 45 46# BITS is used as extension for files which are available in a 32 bit 47# and a 64 bit version to simplify shared Makefiles. 48# e.g.: obj-y += foo_$(BITS).o 49export BITS 50 51ifdef CONFIG_X86_NEED_RELOCS 52 LDFLAGS_vmlinux := --emit-relocs --discard-none 53endif 54 55# 56# Prevent GCC from generating any FP code by mistake. 57# 58# This must happen before we try the -mpreferred-stack-boundary, see: 59# 60# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53383 61# 62KBUILD_CFLAGS += -mno-sse -mno-mmx -mno-sse2 -mno-3dnow 63KBUILD_CFLAGS += $(call cc-option,-mno-avx,) 64 65# Intel CET isn't enabled in the kernel 66KBUILD_CFLAGS += $(call cc-option,-fcf-protection=none) 67 68ifeq ($(CONFIG_X86_32),y) 69 BITS := 32 70 UTS_MACHINE := i386 71 CHECKFLAGS += -D__i386__ 72 73 biarch := $(call cc-option,-m32) 74 KBUILD_AFLAGS += $(biarch) 75 KBUILD_CFLAGS += $(biarch) 76 77 KBUILD_CFLAGS += -msoft-float -mregparm=3 -freg-struct-return 78 79 # Never want PIC in a 32-bit kernel, prevent breakage with GCC built 80 # with nonstandard options 81 KBUILD_CFLAGS += -fno-pic 82 83 # Align the stack to the register width instead of using the default 84 # alignment of 16 bytes. This reduces stack usage and the number of 85 # alignment instructions. 86 KBUILD_CFLAGS += $(call cc-option,$(cc_stack_align4)) 87 88 # Disable unit-at-a-time mode on pre-gcc-4.0 compilers, it makes gcc use 89 # a lot more stack due to the lack of sharing of stacklots: 90 KBUILD_CFLAGS += $(call cc-ifversion, -lt, 0400, \ 91 $(call cc-option,-fno-unit-at-a-time)) 92 93 # CPU-specific tuning. Anything which can be shared with UML should go here. 94 include arch/x86/Makefile_32.cpu 95 KBUILD_CFLAGS += $(cflags-y) 96 97 # temporary until string.h is fixed 98 KBUILD_CFLAGS += -ffreestanding 99else 100 BITS := 64 101 UTS_MACHINE := x86_64 102 CHECKFLAGS += -D__x86_64__ -m64 103 104 biarch := -m64 105 KBUILD_AFLAGS += -m64 106 KBUILD_CFLAGS += -m64 107 108 # Align jump targets to 1 byte, not the default 16 bytes: 109 KBUILD_CFLAGS += $(call cc-option,-falign-jumps=1) 110 111 # Pack loops tightly as well: 112 KBUILD_CFLAGS += $(call cc-option,-falign-loops=1) 113 114 # Don't autogenerate traditional x87 instructions 115 KBUILD_CFLAGS += $(call cc-option,-mno-80387) 116 KBUILD_CFLAGS += $(call cc-option,-mno-fp-ret-in-387) 117 118 KBUILD_CFLAGS += -fno-pic 119 120 # By default gcc and clang use a stack alignment of 16 bytes for x86. 121 # However the standard kernel entry on x86-64 leaves the stack on an 122 # 8-byte boundary. If the compiler isn't informed about the actual 123 # alignment it will generate extra alignment instructions for the 124 # default alignment which keep the stack *mis*aligned. 125 # Furthermore an alignment to the register width reduces stack usage 126 # and the number of alignment instructions. 127 KBUILD_CFLAGS += $(call cc-option,$(cc_stack_align8)) 128 129 # Use -mskip-rax-setup if supported. 130 KBUILD_CFLAGS += $(call cc-option,-mskip-rax-setup) 131 132 # FIXME - should be integrated in Makefile.cpu (Makefile_32.cpu) 133 cflags-$(CONFIG_MK8) += $(call cc-option,-march=k8) 134 cflags-$(CONFIG_MPSC) += $(call cc-option,-march=nocona) 135 136 cflags-$(CONFIG_MCORE2) += \ 137 $(call cc-option,-march=core2,$(call cc-option,-mtune=generic)) 138 cflags-$(CONFIG_MATOM) += $(call cc-option,-march=atom) \ 139 $(call cc-option,-mtune=atom,$(call cc-option,-mtune=generic)) 140 cflags-$(CONFIG_GENERIC_CPU) += $(call cc-option,-mtune=generic) 141 KBUILD_CFLAGS += $(cflags-y) 142 143 KBUILD_CFLAGS += -mno-red-zone 144 KBUILD_CFLAGS += -mcmodel=kernel 145 146 # -funit-at-a-time shrinks the kernel .text considerably 147 # unfortunately it makes reading oopses harder. 148 KBUILD_CFLAGS += $(call cc-option,-funit-at-a-time) 149 150 # this works around some issues with generating unwind tables in older gccs 151 # newer gccs do it by default 152 KBUILD_CFLAGS += $(call cc-option,-maccumulate-outgoing-args) 153endif 154 155# Make sure compiler does not have buggy stack-protector support. 156ifdef CONFIG_CC_STACKPROTECTOR 157 cc_has_sp := $(srctree)/scripts/gcc-x86_$(BITS)-has-stack-protector.sh 158 ifneq ($(shell $(CONFIG_SHELL) $(cc_has_sp) $(CC) $(KBUILD_CPPFLAGS) $(biarch)),y) 159 $(warning stack-protector enabled but compiler support broken) 160 endif 161endif 162 163ifdef CONFIG_X86_X32 164 x32_ld_ok := $(call try-run,\ 165 /bin/echo -e '1: .quad 1b' | \ 166 $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" - && \ 167 $(OBJCOPY) -O elf32-x86-64 "$$TMP" "$$TMPO" && \ 168 $(LD) -m elf32_x86_64 "$$TMPO" -o "$$TMP",y,n) 169 ifeq ($(x32_ld_ok),y) 170 CONFIG_X86_X32_ABI := y 171 KBUILD_AFLAGS += -DCONFIG_X86_X32_ABI 172 KBUILD_CFLAGS += -DCONFIG_X86_X32_ABI 173 else 174 $(warning CONFIG_X86_X32 enabled but no binutils support) 175 endif 176endif 177export CONFIG_X86_X32_ABI 178 179# Don't unroll struct assignments with kmemcheck enabled 180ifeq ($(CONFIG_KMEMCHECK),y) 181 KBUILD_CFLAGS += $(call cc-option,-fno-builtin-memcpy) 182endif 183 184# Stackpointer is addressed different for 32 bit and 64 bit x86 185sp-$(CONFIG_X86_32) := esp 186sp-$(CONFIG_X86_64) := rsp 187 188# do binutils support CFI? 189cfi := $(call as-instr,.cfi_startproc\n.cfi_rel_offset $(sp-y)$(comma)0\n.cfi_endproc,-DCONFIG_AS_CFI=1) 190# is .cfi_signal_frame supported too? 191cfi-sigframe := $(call as-instr,.cfi_startproc\n.cfi_signal_frame\n.cfi_endproc,-DCONFIG_AS_CFI_SIGNAL_FRAME=1) 192cfi-sections := $(call as-instr,.cfi_sections .debug_frame,-DCONFIG_AS_CFI_SECTIONS=1) 193 194# does binutils support specific instructions? 195asinstr := $(call as-instr,fxsaveq (%rax),-DCONFIG_AS_FXSAVEQ=1) 196asinstr += $(call as-instr,pshufb %xmm0$(comma)%xmm0,-DCONFIG_AS_SSSE3=1) 197asinstr += $(call as-instr,crc32l %eax$(comma)%eax,-DCONFIG_AS_CRC32=1) 198avx_instr := $(call as-instr,vxorps %ymm0$(comma)%ymm1$(comma)%ymm2,-DCONFIG_AS_AVX=1) 199avx2_instr :=$(call as-instr,vpbroadcastb %xmm0$(comma)%ymm1,-DCONFIG_AS_AVX2=1) 200sha1_ni_instr :=$(call as-instr,sha1msg1 %xmm0$(comma)%xmm1,-DCONFIG_AS_SHA1_NI=1) 201sha256_ni_instr :=$(call as-instr,sha256msg1 %xmm0$(comma)%xmm1,-DCONFIG_AS_SHA256_NI=1) 202 203KBUILD_AFLAGS += $(cfi) $(cfi-sigframe) $(cfi-sections) $(asinstr) $(avx_instr) $(avx2_instr) $(sha1_ni_instr) $(sha256_ni_instr) 204KBUILD_CFLAGS += $(cfi) $(cfi-sigframe) $(cfi-sections) $(asinstr) $(avx_instr) $(avx2_instr) $(sha1_ni_instr) $(sha256_ni_instr) 205 206LDFLAGS := -m elf_$(UTS_MACHINE) 207 208# 209# The 64-bit kernel must be aligned to 2MB. Pass -z max-page-size=0x200000 to 210# the linker to force 2MB page size regardless of the default page size used 211# by the linker. 212# 213ifdef CONFIG_X86_64 214LDFLAGS += $(call ld-option, -z max-page-size=0x200000) 215endif 216 217# Speed up the build 218KBUILD_CFLAGS += -pipe 219# Workaround for a gcc prelease that unfortunately was shipped in a suse release 220KBUILD_CFLAGS += -Wno-sign-compare 221# 222KBUILD_CFLAGS += -fno-asynchronous-unwind-tables 223 224KBUILD_CFLAGS += $(mflags-y) 225KBUILD_AFLAGS += $(mflags-y) 226 227# Avoid indirect branches in kernel to deal with Spectre 228ifdef CONFIG_RETPOLINE 229 RETPOLINE_CFLAGS += $(call cc-option,-mindirect-branch=thunk-extern -mindirect-branch-register) 230 ifneq ($(RETPOLINE_CFLAGS),) 231 KBUILD_CFLAGS += $(RETPOLINE_CFLAGS) -DRETPOLINE 232 endif 233endif 234 235archscripts: scripts_basic 236 $(Q)$(MAKE) $(build)=arch/x86/tools relocs 237 238### 239# Syscall table generation 240 241archheaders: 242 $(Q)$(MAKE) $(build)=arch/x86/entry/syscalls all 243 244archprepare: 245ifeq ($(CONFIG_KEXEC_FILE),y) 246 $(Q)$(MAKE) $(build)=arch/x86/purgatory arch/x86/purgatory/kexec-purgatory.c 247endif 248 249### 250# Kernel objects 251 252head-y := arch/x86/kernel/head_$(BITS).o 253head-y += arch/x86/kernel/head$(BITS).o 254head-y += arch/x86/kernel/head.o 255 256libs-y += arch/x86/lib/ 257 258# See arch/x86/Kbuild for content of core part of the kernel 259core-y += arch/x86/ 260 261# drivers-y are linked after core-y 262drivers-$(CONFIG_MATH_EMULATION) += arch/x86/math-emu/ 263drivers-$(CONFIG_PCI) += arch/x86/pci/ 264 265# must be linked after kernel/ 266drivers-$(CONFIG_OPROFILE) += arch/x86/oprofile/ 267 268# suspend and hibernation support 269drivers-$(CONFIG_PM) += arch/x86/power/ 270 271drivers-$(CONFIG_FB) += arch/x86/video/ 272 273drivers-$(CONFIG_RAS) += arch/x86/ras/ 274 275#### 276# boot loader support. Several targets are kept for legacy purposes 277 278boot := arch/x86/boot 279 280BOOT_TARGETS = bzlilo bzdisk fdimage fdimage144 fdimage288 isoimage 281 282PHONY += bzImage $(BOOT_TARGETS) 283 284# Default kernel to build 285all: bzImage 286 287# KBUILD_IMAGE specify target image being built 288KBUILD_IMAGE := $(boot)/bzImage 289 290bzImage: vmlinux 291ifeq ($(CONFIG_X86_DECODER_SELFTEST),y) 292 $(Q)$(MAKE) $(build)=arch/x86/tools posttest 293endif 294 $(Q)$(MAKE) $(build)=$(boot) $(KBUILD_IMAGE) 295 $(Q)mkdir -p $(objtree)/arch/$(UTS_MACHINE)/boot 296 $(Q)ln -fsn ../../x86/boot/bzImage $(objtree)/arch/$(UTS_MACHINE)/boot/$@ 297 298$(BOOT_TARGETS): vmlinux 299 $(Q)$(MAKE) $(build)=$(boot) $@ 300 301PHONY += install 302install: 303 $(Q)$(MAKE) $(build)=$(boot) $@ 304 305PHONY += vdso_install 306vdso_install: 307 $(Q)$(MAKE) $(build)=arch/x86/entry/vdso $@ 308 309archclean: 310 $(Q)rm -rf $(objtree)/arch/i386 311 $(Q)rm -rf $(objtree)/arch/x86_64 312 $(Q)$(MAKE) $(clean)=$(boot) 313 $(Q)$(MAKE) $(clean)=arch/x86/tools 314 $(Q)$(MAKE) $(clean)=arch/x86/purgatory 315 316define archhelp 317 echo '* bzImage - Compressed kernel image (arch/x86/boot/bzImage)' 318 echo ' install - Install kernel using' 319 echo ' (your) ~/bin/$(INSTALLKERNEL) or' 320 echo ' (distribution) /sbin/$(INSTALLKERNEL) or' 321 echo ' install to $$(INSTALL_PATH) and run lilo' 322 echo ' fdimage - Create 1.4MB boot floppy image (arch/x86/boot/fdimage)' 323 echo ' fdimage144 - Create 1.4MB boot floppy image (arch/x86/boot/fdimage)' 324 echo ' fdimage288 - Create 2.8MB boot floppy image (arch/x86/boot/fdimage)' 325 echo ' isoimage - Create a boot CD-ROM image (arch/x86/boot/image.iso)' 326 echo ' bzdisk/fdimage*/isoimage also accept:' 327 echo ' FDARGS="..." arguments for the booted kernel' 328 echo ' FDINITRD=file initrd for the booted kernel' 329endef 330