arch/x86/Makefile

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