arch/x86/Makefile

   1 # SPDX-License-Identifier: GPL-2.0
   2 # Unified Makefile for i386 and x86_64
   3
   4 # select defconfig based on actual architecture
   5 ifeq ($(ARCH),x86)
   6   ifeq ($(shell uname -m),x86_64)
   7         KBUILD_DEFCONFIG := x86_64_defconfig
   8   else
   9         KBUILD_DEFCONFIG := i386_defconfig
  10   endif
  11 else
  12         KBUILD_DEFCONFIG := $(ARCH)_defconfig
  13 endif
  14
  15 # For gcc stack alignment is specified with -mpreferred-stack-boundary,
  16 # clang has the option -mstack-alignment for that purpose.
  17 ifneq ($(call cc-option, -mpreferred-stack-boundary=4),)
  18       cc_stack_align4 := -mpreferred-stack-boundary=2
  19       cc_stack_align8 := -mpreferred-stack-boundary=3
  20 else ifneq ($(call cc-option, -mstack-alignment=16),)
  21       cc_stack_align4 := -mstack-alignment=4
  22       cc_stack_align8 := -mstack-alignment=8
  23 endif
  24
  25 # How to compile the 16-bit code.  Note we always compile for -march=i386;
  26 # that way we can complain to the user if the CPU is insufficient.
  27 #
  28 # The -m16 option is supported by GCC >= 4.9 and clang >= 3.5. For
  29 # older versions of GCC, include an *assembly* header to make sure that
  30 # gcc doesn't play any games behind our back.
  31 CODE16GCC_CFLAGS := -m32 -Wa,$(srctree)/arch/x86/boot/code16gcc.h
  32 M16_CFLAGS       := $(call cc-option, -m16, $(CODE16GCC_CFLAGS))
  33
  34 REALMODE_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
  39 REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -ffreestanding)
  40 REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -fno-stack-protector)
  41 REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), $(cc_stack_align4))
  42 export REALMODE_CFLAGS
  43
  44 # BITS is used as extension for files which are available in a 32 bit
  45 # and a 64 bit version to simplify shared Makefiles.
  46 # e.g.: obj-y += foo_$(BITS).o
  47 export BITS
  48
  49 ifdef CONFIG_X86_NEED_RELOCS
  50         LDFLAGS_vmlinux := --emit-relocs
  51 endif
  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 #
  60 KBUILD_CFLAGS += -mno-sse -mno-mmx -mno-sse2 -mno-3dnow
  61 KBUILD_CFLAGS += $(call cc-option,-mno-avx,)
  62
  63 ifeq ($(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
  94 else
  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)
 142 endif
 143
 144 ifdef 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
 157 endif
 158 export 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 #
 165 ifdef 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
 181 endif
 182
 183 ifndef CC_HAVE_ASM_GOTO
 184   $(error Compiler lacks asm-goto support.)
 185 endif
 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 #
 193 ifdef CONFIG_JUMP_LABEL
 194   ifneq ($(ACCUMULATE_OUTGOING_ARGS), 1)
 195         ACCUMULATE_OUTGOING_ARGS = $(call cc-if-fullversion, -lt, 040502, 1)
 196   endif
 197 endif
 198
 199 ifeq ($(ACCUMULATE_OUTGOING_ARGS), 1)
 200         # This compiler flag is not supported by Clang:
 201         KBUILD_CFLAGS += $(call cc-option,-maccumulate-outgoing-args,)
 202 endif
 203
 204 # Stackpointer is addressed different for 32 bit and 64 bit x86
 205 sp-$(CONFIG_X86_32) := esp
 206 sp-$(CONFIG_X86_64) := rsp
 207
 208 # do binutils support CFI?
 209 cfi := $(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?
 211 cfi-sigframe := $(call as-instr,.cfi_startproc\n.cfi_signal_frame\n.cfi_endproc,-DCONFIG_AS_CFI_SIGNAL_FRAME=1)
 212 cfi-sections := $(call as-instr,.cfi_sections .debug_frame,-DCONFIG_AS_CFI_SECTIONS=1)
 213
 214 # does binutils support specific instructions?
 215 asinstr := $(call as-instr,fxsaveq (%rax),-DCONFIG_AS_FXSAVEQ=1)
 216 asinstr += $(call as-instr,pshufb %xmm0$(comma)%xmm0,-DCONFIG_AS_SSSE3=1)
 217 asinstr += $(call as-instr,crc32l %eax$(comma)%eax,-DCONFIG_AS_CRC32=1)
 218 avx_instr := $(call as-instr,vxorps %ymm0$(comma)%ymm1$(comma)%ymm2,-DCONFIG_AS_AVX=1)
 219 avx2_instr :=$(call as-instr,vpbroadcastb %xmm0$(comma)%ymm1,-DCONFIG_AS_AVX2=1)
 220 avx512_instr :=$(call as-instr,vpmovm2b %k1$(comma)%zmm5,-DCONFIG_AS_AVX512=1)
 221 sha1_ni_instr :=$(call as-instr,sha1msg1 %xmm0$(comma)%xmm1,-DCONFIG_AS_SHA1_NI=1)
 222 sha256_ni_instr :=$(call as-instr,sha256msg1 %xmm0$(comma)%xmm1,-DCONFIG_AS_SHA256_NI=1)
 223
 224 KBUILD_AFLAGS += $(cfi) $(cfi-sigframe) $(cfi-sections) $(asinstr) $(avx_instr) $(avx2_instr) $(avx512_instr) $(sha1_ni_instr) $(sha256_ni_instr)
 225 KBUILD_CFLAGS += $(cfi) $(cfi-sigframe) $(cfi-sections) $(asinstr) $(avx_instr) $(avx2_instr) $(avx512_instr) $(sha1_ni_instr) $(sha256_ni_instr)
 226
 227 LDFLAGS := -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 #
 234 ifdef CONFIG_X86_64
 235 LDFLAGS += $(call ld-option, -z max-page-size=0x200000)
 236 endif
 237
 238 # Speed up the build
 239 KBUILD_CFLAGS += -pipe
 240 # Workaround for a gcc prelease that unfortunately was shipped in a suse release
 241 KBUILD_CFLAGS += -Wno-sign-compare
 242 #
 243 KBUILD_CFLAGS += -fno-asynchronous-unwind-tables
 244
 245 # Avoid indirect branches in kernel to deal with Spectre
 246 ifdef CONFIG_RETPOLINE
 247 ifneq ($(RETPOLINE_CFLAGS),)
 248   KBUILD_CFLAGS += $(RETPOLINE_CFLAGS) -DRETPOLINE
 249 endif
 250 endif
 251
 252 archscripts: scripts_basic
 253         $(Q)$(MAKE) $(build)=arch/x86/tools relocs
 254
 255 ###
 256 # Syscall table generation
 257
 258 archheaders:
 259         $(Q)$(MAKE) $(build)=arch/x86/entry/syscalls all
 260
 261 archprepare:
 262 ifeq ($(CONFIG_KEXEC_FILE),y)
 263         $(Q)$(MAKE) $(build)=arch/x86/purgatory arch/x86/purgatory/kexec-purgatory.c
 264 endif
 265
 266 ###
 267 # Kernel objects
 268
 269 head-y := arch/x86/kernel/head_$(BITS).o
 270 head-y += arch/x86/kernel/head$(BITS).o
 271 head-y += arch/x86/kernel/ebda.o
 272 head-y += arch/x86/kernel/platform-quirks.o
 273
 274 libs-y  += arch/x86/lib/
 275
 276 # See arch/x86/Kbuild for content of core part of the kernel
 277 core-y += arch/x86/
 278
 279 # drivers-y are linked after core-y
 280 drivers-$(CONFIG_MATH_EMULATION) += arch/x86/math-emu/
 281 drivers-$(CONFIG_PCI)            += arch/x86/pci/
 282
 283 # must be linked after kernel/
 284 drivers-$(CONFIG_OPROFILE) += arch/x86/oprofile/
 285
 286 # suspend and hibernation support
 287 drivers-$(CONFIG_PM) += arch/x86/power/
 288
 289 drivers-$(CONFIG_FB) += arch/x86/video/
 290
 291 ####
 292 # boot loader support. Several targets are kept for legacy purposes
 293
 294 boot := arch/x86/boot
 295
 296 BOOT_TARGETS = bzlilo bzdisk fdimage fdimage144 fdimage288 isoimage
 297
 298 PHONY += bzImage $(BOOT_TARGETS)
 299
 300 # Default kernel to build
 301 all: bzImage
 302
 303 # KBUILD_IMAGE specify target image being built
 304 KBUILD_IMAGE := $(boot)/bzImage
 305
 306 bzImage: vmlinux
 307 ifeq ($(CONFIG_X86_DECODER_SELFTEST),y)
 308         $(Q)$(MAKE) $(build)=arch/x86/tools posttest
 309 endif
 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
 317 PHONY += install
 318 install:
 319         $(Q)$(MAKE) $(build)=$(boot) $@
 320
 321 PHONY += vdso_install
 322 vdso_install:
 323         $(Q)$(MAKE) $(build)=arch/x86/entry/vdso $@
 324
 325 archclean:
 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
 332 define 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'
 345 endef