1 files changed, 322 insertions, 0 deletions
diff --git a/arch/x86/Makefile b/arch/x86/Makefile
new file mode 100644
index 000000000..1f796050c
--- /dev/null
+++ b/arch/x86/Makefile
@@ -0,0 +1,322 @@
+# SPDX-License-Identifier: GPL-2.0
+# Unified Makefile for i386 and x86_64
+
+# select defconfig based on actual architecture
+ifeq ($(ARCH),x86)
+  ifeq ($(shell uname -m),x86_64)
+        KBUILD_DEFCONFIG := x86_64_defconfig
+  else
+        KBUILD_DEFCONFIG := i386_defconfig
+  endif
+else
+        KBUILD_DEFCONFIG := $(ARCH)_defconfig
+endif
+
+# For gcc stack alignment is specified with -mpreferred-stack-boundary,
+# clang has the option -mstack-alignment for that purpose.
+ifneq ($(call cc-option, -mpreferred-stack-boundary=4),)
+      cc_stack_align4 := -mpreferred-stack-boundary=2
+      cc_stack_align8 := -mpreferred-stack-boundary=3
+else ifneq ($(call cc-option, -mstack-alignment=16),)
+      cc_stack_align4 := -mstack-alignment=4
+      cc_stack_align8 := -mstack-alignment=8
+endif
+
+# How to compile the 16-bit code.  Note we always compile for -march=i386;
+# that way we can complain to the user if the CPU is insufficient.
+#
+# The -m16 option is supported by GCC >= 4.9 and clang >= 3.5. For
+# older versions of GCC, include an *assembly* header to make sure that
+# gcc doesn't play any games behind our back.
+CODE16GCC_CFLAGS := -m32 -Wa,$(srctree)/arch/x86/boot/code16gcc.h
+M16_CFLAGS	 := $(call cc-option, -m16, $(CODE16GCC_CFLAGS))
+
+REALMODE_CFLAGS	:= $(M16_CFLAGS) -g -Os -DDISABLE_BRANCH_PROFILING -D__DISABLE_EXPORTS \
+		   -Wall -Wstrict-prototypes -march=i386 -mregparm=3 \
+		   -fno-strict-aliasing -fomit-frame-pointer -fno-pic \
+		   -mno-mmx -mno-sse $(call cc-option,-fcf-protection=none)
+
+REALMODE_CFLAGS += -ffreestanding
+REALMODE_CFLAGS += -fno-stack-protector
+REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -Wno-address-of-packed-member)
+REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), $(cc_stack_align4))
+REALMODE_CFLAGS += $(CLANG_FLAGS)
+export REALMODE_CFLAGS
+
+# BITS is used as extension for files which are available in a 32 bit
+# and a 64 bit version to simplify shared Makefiles.
+# e.g.: obj-y += foo_$(BITS).o
+export BITS
+
+#
+# Prevent GCC from generating any FP code by mistake.
+#
+# This must happen before we try the -mpreferred-stack-boundary, see:
+#
+#    https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53383
+#
+KBUILD_CFLAGS += -mno-sse -mno-mmx -mno-sse2 -mno-3dnow
+KBUILD_CFLAGS += $(call cc-option,-mno-avx,)
+
+# Intel CET isn't enabled in the kernel
+KBUILD_CFLAGS += $(call cc-option,-fcf-protection=none)
+
+ifeq ($(CONFIG_X86_32),y)
+        BITS := 32
+        UTS_MACHINE := i386
+        CHECKFLAGS += -D__i386__
+
+        biarch := $(call cc-option,-m32)
+        KBUILD_AFLAGS += $(biarch)
+        KBUILD_CFLAGS += $(biarch)
+
+        KBUILD_CFLAGS += -msoft-float -mregparm=3 -freg-struct-return
+
+        # Never want PIC in a 32-bit kernel, prevent breakage with GCC built
+        # with nonstandard options
+        KBUILD_CFLAGS += -fno-pic
+
+        # Align the stack to the register width instead of using the default
+        # alignment of 16 bytes. This reduces stack usage and the number of
+        # alignment instructions.
+        KBUILD_CFLAGS += $(call cc-option,$(cc_stack_align4))
+
+        # CPU-specific tuning. Anything which can be shared with UML should go here.
+        include arch/x86/Makefile_32.cpu
+        KBUILD_CFLAGS += $(cflags-y)
+
+        # temporary until string.h is fixed
+        KBUILD_CFLAGS += -ffreestanding
+else
+        BITS := 64
+        UTS_MACHINE := x86_64
+        CHECKFLAGS += -D__x86_64__
+
+        biarch := -m64
+        KBUILD_AFLAGS += -m64
+        KBUILD_CFLAGS += -m64
+
+        # Align jump targets to 1 byte, not the default 16 bytes:
+        KBUILD_CFLAGS += $(call cc-option,-falign-jumps=1)
+
+        # Pack loops tightly as well:
+        KBUILD_CFLAGS += $(call cc-option,-falign-loops=1)
+
+        # Don't autogenerate traditional x87 instructions
+        KBUILD_CFLAGS += $(call cc-option,-mno-80387)
+        KBUILD_CFLAGS += $(call cc-option,-mno-fp-ret-in-387)
+
+        # By default gcc and clang use a stack alignment of 16 bytes for x86.
+        # However the standard kernel entry on x86-64 leaves the stack on an
+        # 8-byte boundary. If the compiler isn't informed about the actual
+        # alignment it will generate extra alignment instructions for the
+        # default alignment which keep the stack *mis*aligned.
+        # Furthermore an alignment to the register width reduces stack usage
+        # and the number of alignment instructions.
+        KBUILD_CFLAGS += $(call cc-option,$(cc_stack_align8))
+
+	# Use -mskip-rax-setup if supported.
+	KBUILD_CFLAGS += $(call cc-option,-mskip-rax-setup)
+
+        # FIXME - should be integrated in Makefile.cpu (Makefile_32.cpu)
+        cflags-$(CONFIG_MK8) += $(call cc-option,-march=k8)
+        cflags-$(CONFIG_MPSC) += $(call cc-option,-march=nocona)
+
+        cflags-$(CONFIG_MCORE2) += \
+                $(call cc-option,-march=core2,$(call cc-option,-mtune=generic))
+	cflags-$(CONFIG_MATOM) += $(call cc-option,-march=atom) \
+		$(call cc-option,-mtune=atom,$(call cc-option,-mtune=generic))
+        cflags-$(CONFIG_GENERIC_CPU) += $(call cc-option,-mtune=generic)
+        KBUILD_CFLAGS += $(cflags-y)
+
+        KBUILD_CFLAGS += -mno-red-zone
+        KBUILD_CFLAGS += -mcmodel=kernel
+endif
+
+ifdef CONFIG_X86_X32
+	x32_ld_ok := $(call try-run,\
+			/bin/echo -e '1: .quad 1b' | \
+			$(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" - && \
+			$(OBJCOPY) -O elf32-x86-64 "$$TMP" "$$TMPO" && \
+			$(LD) -m elf32_x86_64 "$$TMPO" -o "$$TMP",y,n)
+        ifeq ($(x32_ld_ok),y)
+                CONFIG_X86_X32_ABI := y
+                KBUILD_AFLAGS += -DCONFIG_X86_X32_ABI
+                KBUILD_CFLAGS += -DCONFIG_X86_X32_ABI
+        else
+                $(warning CONFIG_X86_X32 enabled but no binutils support)
+        endif
+endif
+export CONFIG_X86_X32_ABI
+
+#
+# If the function graph tracer is used with mcount instead of fentry,
+# '-maccumulate-outgoing-args' is needed to prevent a GCC bug
+# (https://gcc.gnu.org/bugzilla/show_bug.cgi?id=42109)
+#
+ifdef CONFIG_FUNCTION_GRAPH_TRACER
+  ifndef CONFIG_HAVE_FENTRY
+	ACCUMULATE_OUTGOING_ARGS := 1
+  else
+    ifeq ($(call cc-option-yn, -mfentry), n)
+	ACCUMULATE_OUTGOING_ARGS := 1
+
+	# GCC ignores '-maccumulate-outgoing-args' when used with '-Os'.
+	# If '-Os' is enabled, disable it and print a warning.
+        ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE
+          undefine CONFIG_CC_OPTIMIZE_FOR_SIZE
+          $(warning Disabling CONFIG_CC_OPTIMIZE_FOR_SIZE.  Your compiler does not have -mfentry so you cannot optimize for size with CONFIG_FUNCTION_GRAPH_TRACER.)
+        endif
+
+    endif
+  endif
+endif
+
+ifeq ($(ACCUMULATE_OUTGOING_ARGS), 1)
+	# This compiler flag is not supported by Clang:
+	KBUILD_CFLAGS += $(call cc-option,-maccumulate-outgoing-args,)
+endif
+
+# Workaround for a gcc prelease that unfortunately was shipped in a suse release
+KBUILD_CFLAGS += -Wno-sign-compare
+#
+KBUILD_CFLAGS += -fno-asynchronous-unwind-tables
+
+# Avoid indirect branches in kernel to deal with Spectre
+ifdef CONFIG_RETPOLINE
+  KBUILD_CFLAGS += $(RETPOLINE_CFLAGS)
+  # Additionally, avoid generating expensive indirect jumps which
+  # are subject to retpolines for small number of switch cases.
+  # clang turns off jump table generation by default when under
+  # retpoline builds, however, gcc does not for x86. This has
+  # only been fixed starting from gcc stable version 8.4.0 and
+  # onwards, but not for older ones. See gcc bug #86952.
+  ifndef CONFIG_CC_IS_CLANG
+    KBUILD_CFLAGS += $(call cc-option,-fno-jump-tables)
+  endif
+endif
+
+ifdef CONFIG_SLS
+  KBUILD_CFLAGS += -mharden-sls=all
+endif
+
+KBUILD_LDFLAGS += -m elf_$(UTS_MACHINE)
+
+ifdef CONFIG_X86_NEED_RELOCS
+LDFLAGS_vmlinux := --emit-relocs --discard-none
+else
+LDFLAGS_vmlinux :=
+endif
+
+#
+# The 64-bit kernel must be aligned to 2MB.  Pass -z max-page-size=0x200000 to
+# the linker to force 2MB page size regardless of the default page size used
+# by the linker.
+#
+ifdef CONFIG_X86_64
+LDFLAGS_vmlinux += -z max-page-size=0x200000
+endif
+
+
+archscripts: scripts_basic
+	$(Q)$(MAKE) $(build)=arch/x86/tools relocs
+
+###
+# Syscall table generation
+
+archheaders:
+	$(Q)$(MAKE) $(build)=arch/x86/entry/syscalls all
+
+###
+# Kernel objects
+
+head-y := arch/x86/kernel/head_$(BITS).o
+head-y += arch/x86/kernel/head$(BITS).o
+head-y += arch/x86/kernel/ebda.o
+head-y += arch/x86/kernel/platform-quirks.o
+
+libs-y  += arch/x86/lib/
+
+# See arch/x86/Kbuild for content of core part of the kernel
+core-y += arch/x86/
+
+# drivers-y are linked after core-y
+drivers-$(CONFIG_MATH_EMULATION) += arch/x86/math-emu/
+drivers-$(CONFIG_PCI)            += arch/x86/pci/
+
+# must be linked after kernel/
+drivers-$(CONFIG_OPROFILE) += arch/x86/oprofile/
+
+# suspend and hibernation support
+drivers-$(CONFIG_PM) += arch/x86/power/
+
+drivers-$(CONFIG_FB) += arch/x86/video/
+
+####
+# boot loader support. Several targets are kept for legacy purposes
+
+boot := arch/x86/boot
+
+BOOT_TARGETS = bzdisk fdimage fdimage144 fdimage288 isoimage
+
+PHONY += bzImage $(BOOT_TARGETS)
+
+# Default kernel to build
+all: bzImage
+
+# KBUILD_IMAGE specify target image being built
+KBUILD_IMAGE := $(boot)/bzImage
+
+bzImage: vmlinux
+ifeq ($(CONFIG_X86_DECODER_SELFTEST),y)
+	$(Q)$(MAKE) $(build)=arch/x86/tools posttest
+endif
+	$(Q)$(MAKE) $(build)=$(boot) $(KBUILD_IMAGE)
+	$(Q)mkdir -p $(objtree)/arch/$(UTS_MACHINE)/boot
+	$(Q)ln -fsn ../../x86/boot/bzImage $(objtree)/arch/$(UTS_MACHINE)/boot/$@
+
+$(BOOT_TARGETS): vmlinux
+	$(Q)$(MAKE) $(build)=$(boot) $@
+
+PHONY += install bzlilo
+install bzlilo:
+	$(Q)$(MAKE) $(build)=$(boot) $@
+
+PHONY += vdso_install
+vdso_install:
+	$(Q)$(MAKE) $(build)=arch/x86/entry/vdso $@
+
+archprepare: checkbin
+checkbin:
+ifndef CONFIG_CC_HAS_ASM_GOTO
+	@echo Compiler lacks asm-goto support.
+	@exit 1
+endif
+ifdef CONFIG_RETPOLINE
+ifeq ($(RETPOLINE_CFLAGS),)
+	@echo "You are building kernel with non-retpoline compiler." >&2
+	@echo "Please update your compiler." >&2
+	@false
+endif
+endif
+
+archclean:
+	$(Q)rm -rf $(objtree)/arch/i386
+	$(Q)rm -rf $(objtree)/arch/x86_64
+	$(Q)$(MAKE) $(clean)=$(boot)
+	$(Q)$(MAKE) $(clean)=arch/x86/tools
+
+define archhelp
+  echo  '* bzImage      - Compressed kernel image (arch/x86/boot/bzImage)'
+  echo  '  install      - Install kernel using'
+  echo  '                  (your) ~/bin/$(INSTALLKERNEL) or'
+  echo  '                  (distribution) /sbin/$(INSTALLKERNEL) or'
+  echo  '                  install to $$(INSTALL_PATH) and run lilo'
+  echo  '  fdimage      - Create 1.4MB boot floppy image (arch/x86/boot/fdimage)'
+  echo  '  fdimage144   - Create 1.4MB boot floppy image (arch/x86/boot/fdimage)'
+  echo  '  fdimage288   - Create 2.8MB boot floppy image (arch/x86/boot/fdimage)'
+  echo  '  isoimage     - Create a boot CD-ROM image (arch/x86/boot/image.iso)'
+  echo  '                  bzdisk/fdimage*/isoimage also accept:'
+  echo  '                  FDARGS="..."  arguments for the booted kernel'
+  echo  '                  FDINITRD=file initrd for the booted kernel'
+endef