arch/arm64/Makefile - linux - Git at Google

 #
 # arch/arm64/Makefile
 #
 # This file is included by the global makefile so that you can add your own
 # architecture-specific flags and dependencies.
 #
 # This file is subject to the terms and conditions of the GNU General Public
 # License.  See the file "COPYING" in the main directory of this archive
 # for more details.
 #
 # Copyright (C) 1995-2001 by Russell King

 LDFLAGS_vmlinux	:=--no-undefined -X

 ifeq ($(CONFIG_RELOCATABLE), y)
 # Pass --no-apply-dynamic-relocs to restore pre-binutils-2.27 behaviour
 # for relative relocs, since this leads to better Image compression
 # with the relocation offsets always being zero.
 LDFLAGS_vmlinux		+= -shared -Bsymbolic -z notext \
 			$(call ld-option, --no-apply-dynamic-relocs)
 endif

 ifeq ($(CONFIG_ARM64_ERRATUM_843419),y)
   ifeq ($(CONFIG_ARM64_LD_HAS_FIX_ERRATUM_843419),y)
 LDFLAGS_vmlinux	+= --fix-cortex-a53-843419
   endif
 endif

 cc_has_k_constraint := $(call try-run,echo				\
 	'int main(void) {						\
 		asm volatile("and w0, w0, %w0" :: "K" (4294967295));	\
 		return 0;						\
 	}' | $(CC) -S -x c -o "$$TMP" -,,-DCONFIG_CC_HAS_K_CONSTRAINT=1)

 ifeq ($(CONFIG_BROKEN_GAS_INST),y)
 $(warning Detected assembler with broken .inst; disassembly will be unreliable)
 endif

 # The GCC option -ffreestanding is required in order to compile code containing
 # ARM/NEON intrinsics in a non C99-compliant environment (such as the kernel)
 CC_FLAGS_FPU	:= -ffreestanding
 # Enable <arm_neon.h>
 CC_FLAGS_FPU	+= -isystem $(shell $(CC) -print-file-name=include)
 CC_FLAGS_NO_FPU	:= -mgeneral-regs-only

 KBUILD_CFLAGS	+= $(CC_FLAGS_NO_FPU) \
 		   $(compat_vdso) $(cc_has_k_constraint)
 KBUILD_CFLAGS	+= $(call cc-disable-warning, psabi)
 KBUILD_AFLAGS	+= $(compat_vdso)

 KBUILD_RUSTFLAGS += --target=aarch64-unknown-none -Ctarget-feature="-neon"

 KBUILD_CFLAGS	+= $(call cc-option,-mabi=lp64)
 KBUILD_AFLAGS	+= $(call cc-option,-mabi=lp64)

 # Avoid generating .eh_frame* sections.
 ifneq ($(CONFIG_UNWIND_TABLES),y)
 KBUILD_CFLAGS	+= -fno-asynchronous-unwind-tables -fno-unwind-tables
 KBUILD_AFLAGS	+= -fno-asynchronous-unwind-tables -fno-unwind-tables
 KBUILD_RUSTFLAGS += -Cforce-unwind-tables=n
 else
 KBUILD_CFLAGS	+= -fasynchronous-unwind-tables
 KBUILD_AFLAGS	+= -fasynchronous-unwind-tables
 KBUILD_RUSTFLAGS += -Cforce-unwind-tables=y -Zuse-sync-unwind=n
 endif

 ifeq ($(CONFIG_STACKPROTECTOR_PER_TASK),y)
 prepare: stack_protector_prepare
 stack_protector_prepare: prepare0
 	$(eval KBUILD_CFLAGS += -mstack-protector-guard=sysreg		  \
 				-mstack-protector-guard-reg=sp_el0	  \
 				-mstack-protector-guard-offset=$(shell	  \
 			awk '{if ($$2 == "TSK_STACK_CANARY") print $$3;}' \
 					include/generated/asm-offsets.h))
 endif

 ifeq ($(CONFIG_ARM64_BTI_KERNEL),y)
   KBUILD_CFLAGS += -mbranch-protection=pac-ret+bti
   KBUILD_RUSTFLAGS += -Zbranch-protection=bti,pac-ret
 else ifeq ($(CONFIG_ARM64_PTR_AUTH_KERNEL),y)
   KBUILD_RUSTFLAGS += -Zbranch-protection=pac-ret
   ifeq ($(CONFIG_CC_HAS_BRANCH_PROT_PAC_RET),y)
     KBUILD_CFLAGS += -mbranch-protection=pac-ret
   else
     KBUILD_CFLAGS += -msign-return-address=non-leaf
   endif
 else
   KBUILD_CFLAGS += $(call cc-option,-mbranch-protection=none)
 endif

 # Tell the assembler to support instructions from the latest target
 # architecture.
 #
 # For non-integrated assemblers we'll pass this on the command line, and for
 # integrated assemblers we'll define ARM64_ASM_ARCH and ARM64_ASM_PREAMBLE for
 # inline usage.
 #
 # We cannot pass the same arch flag to the compiler as this would allow it to
 # freely generate instructions which are not supported by earlier architecture
 # versions, which would prevent a single kernel image from working on earlier
 # hardware.
 ifeq ($(CONFIG_AS_HAS_ARMV8_5), y)
   asm-arch := armv8.5-a
 else ifeq ($(CONFIG_AS_HAS_ARMV8_4), y)
   asm-arch := armv8.4-a
 else ifeq ($(CONFIG_AS_HAS_ARMV8_3), y)
   asm-arch := armv8.3-a
 else ifeq ($(CONFIG_AS_HAS_ARMV8_2), y)
   asm-arch := armv8.2-a
 endif

 ifdef asm-arch
 KBUILD_CFLAGS	+= -Wa,-march=$(asm-arch) \
 		   -DARM64_ASM_ARCH='"$(asm-arch)"'
 endif

 ifeq ($(CONFIG_SHADOW_CALL_STACK), y)
 KBUILD_CFLAGS	+= -ffixed-x18
 KBUILD_RUSTFLAGS += -Zfixed-x18
 endif

 ifeq ($(CONFIG_CPU_BIG_ENDIAN), y)
 KBUILD_CPPFLAGS	+= -mbig-endian
 CHECKFLAGS	+= -D__AARCH64EB__
 # Prefer the baremetal ELF build target, but not all toolchains include
 # it so fall back to the standard linux version if needed.
 KBUILD_LDFLAGS	+= -EB $(call ld-option, -maarch64elfb, -maarch64linuxb -z norelro)
 UTS_MACHINE	:= aarch64_be
 else
 KBUILD_CPPFLAGS	+= -mlittle-endian
 CHECKFLAGS	+= -D__AARCH64EL__
 # Same as above, prefer ELF but fall back to linux target if needed.
 KBUILD_LDFLAGS	+= -EL $(call ld-option, -maarch64elf, -maarch64linux -z norelro)
 UTS_MACHINE	:= aarch64
 endif

 ifeq ($(CONFIG_LD_IS_LLD), y)
 KBUILD_LDFLAGS	+= -z norelro
 endif

 CHECKFLAGS	+= -D__aarch64__

 ifeq ($(CONFIG_DYNAMIC_FTRACE_WITH_CALL_OPS),y)
   KBUILD_CPPFLAGS += -DCC_USING_PATCHABLE_FUNCTION_ENTRY
   CC_FLAGS_FTRACE := -fpatchable-function-entry=4,2
 else ifeq ($(CONFIG_DYNAMIC_FTRACE_WITH_ARGS),y)
   KBUILD_CPPFLAGS += -DCC_USING_PATCHABLE_FUNCTION_ENTRY
   CC_FLAGS_FTRACE := -fpatchable-function-entry=2
 endif

 ifeq ($(CONFIG_KASAN_SW_TAGS), y)
 KASAN_SHADOW_SCALE_SHIFT := 4
 else ifeq ($(CONFIG_KASAN_GENERIC), y)
 KASAN_SHADOW_SCALE_SHIFT := 3
 endif

 KBUILD_CFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT)
 KBUILD_CPPFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT)
 KBUILD_AFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT)

 libs-y		:= arch/arm64/lib/ $(libs-y)
 libs-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a

 # Default target when executing plain make
 boot		:= arch/arm64/boot

 BOOT_TARGETS	:= Image vmlinuz.efi image.fit

 PHONY += $(BOOT_TARGETS)

 ifeq ($(CONFIG_EFI_ZBOOT),)
 KBUILD_IMAGE	:= $(boot)/Image.gz
 else
 KBUILD_IMAGE	:= $(boot)/vmlinuz.efi
 endif

 all:	$(notdir $(KBUILD_IMAGE))

 image.fit: dtbs

 vmlinuz.efi image.fit: Image
 $(BOOT_TARGETS): vmlinux
 	$(Q)$(MAKE) $(build)=$(boot) $(boot)/$@

 Image.%: Image
 	$(Q)$(MAKE) $(build)=$(boot) $(boot)/$@

 ifeq ($(CONFIG_COMPRESSED_INSTALL),y)
  DEFAULT_KBUILD_IMAGE = $(KBUILD_IMAGE)
 else
  DEFAULT_KBUILD_IMAGE = $(boot)/Image
 endif

 install: KBUILD_IMAGE := $(DEFAULT_KBUILD_IMAGE)
 install zinstall:
 	$(call cmd,install)

 archprepare:
 	$(Q)$(MAKE) $(build)=arch/arm64/tools kapi
 ifeq ($(CONFIG_ARM64_ERRATUM_843419),y)
   ifneq ($(CONFIG_ARM64_LD_HAS_FIX_ERRATUM_843419),y)
 	@echo "warning: ld does not support --fix-cortex-a53-843419; kernel may be susceptible to erratum" >&2
   endif
 endif
 ifeq ($(CONFIG_ARM64_USE_LSE_ATOMICS),y)
   ifneq ($(CONFIG_ARM64_LSE_ATOMICS),y)
 	@echo "warning: LSE atomics not supported by binutils" >&2
   endif
 endif

 ifeq ($(KBUILD_EXTMOD),)
 # We need to generate vdso-offsets.h before compiling certain files in kernel/.
 # In order to do that, we should use the archprepare target, but we can't since
 # asm-offsets.h is included in some files used to generate vdso-offsets.h, and
 # asm-offsets.h is built in prepare0, for which archprepare is a dependency.
 # Therefore we need to generate the header after prepare0 has been made, hence
 # this hack.
 prepare: vdso_prepare
 vdso_prepare: prepare0
 	$(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso \
 	include/generated/vdso-offsets.h arch/arm64/kernel/vdso/vdso.so
 ifdef CONFIG_COMPAT_VDSO
 	$(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso32 \
 	arch/arm64/kernel/vdso32/vdso.so
 endif
 endif

 vdso-install-y				+= arch/arm64/kernel/vdso/vdso.so.dbg
 vdso-install-$(CONFIG_COMPAT_VDSO)	+= arch/arm64/kernel/vdso32/vdso32.so.dbg

 include $(srctree)/scripts/Makefile.defconf

 PHONY += virtconfig
 virtconfig:
 	$(call merge_into_defconfig_override,defconfig,virt)

 define archhelp
   echo  '* Image.gz      - Compressed kernel image (arch/$(ARCH)/boot/Image.gz)'
   echo  '  Image         - Uncompressed kernel image (arch/$(ARCH)/boot/Image)'
   echo  '  image.fit     - Flat Image Tree (arch/$(ARCH)/boot/image.fit)'
   echo  '  install       - Install kernel (compressed if COMPRESSED_INSTALL set)'
   echo  '  zinstall      - Install compressed kernel'
   echo  '                  Install using (your) ~/bin/installkernel or'
   echo  '                  (distribution) /sbin/installkernel or'
   echo  '                  install to $$(INSTALL_PATH) and run lilo'
 endef
	#
	# arch/arm64/Makefile
	#
	# This file is included by the global makefile so that you can add your own
	# architecture-specific flags and dependencies.
	#
	# This file is subject to the terms and conditions of the GNU General Public
	# License. See the file "COPYING" in the main directory of this archive
	# for more details.
	#
	# Copyright (C) 1995-2001 by Russell King

	LDFLAGS_vmlinux :=--no-undefined -X

	ifeq ($(CONFIG_RELOCATABLE), y)
	# Pass --no-apply-dynamic-relocs to restore pre-binutils-2.27 behaviour
	# for relative relocs, since this leads to better Image compression
	# with the relocation offsets always being zero.
	LDFLAGS_vmlinux += -shared -Bsymbolic -z notext \
	$(call ld-option, --no-apply-dynamic-relocs)
	endif

	ifeq ($(CONFIG_ARM64_ERRATUM_843419),y)
	ifeq ($(CONFIG_ARM64_LD_HAS_FIX_ERRATUM_843419),y)
	LDFLAGS_vmlinux += --fix-cortex-a53-843419
	endif
	endif

	cc_has_k_constraint := $(call try-run,echo \
	'int main(void) { \
	asm volatile("and w0, w0, %w0" :: "K" (4294967295)); \
	return 0; \
	}' \| $(CC) -S -x c -o "$$TMP" -,,-DCONFIG_CC_HAS_K_CONSTRAINT=1)

	ifeq ($(CONFIG_BROKEN_GAS_INST),y)
	$(warning Detected assembler with broken .inst; disassembly will be unreliable)
	endif

	# The GCC option -ffreestanding is required in order to compile code containing
	# ARM/NEON intrinsics in a non C99-compliant environment (such as the kernel)
	CC_FLAGS_FPU := -ffreestanding
	# Enable <arm_neon.h>
	CC_FLAGS_FPU += -isystem $(shell $(CC) -print-file-name=include)
	CC_FLAGS_NO_FPU := -mgeneral-regs-only

	KBUILD_CFLAGS += $(CC_FLAGS_NO_FPU) \
	$(compat_vdso) $(cc_has_k_constraint)
	KBUILD_CFLAGS += $(call cc-disable-warning, psabi)
	KBUILD_AFLAGS += $(compat_vdso)

	KBUILD_RUSTFLAGS += --target=aarch64-unknown-none -Ctarget-feature="-neon"

	KBUILD_CFLAGS += $(call cc-option,-mabi=lp64)
	KBUILD_AFLAGS += $(call cc-option,-mabi=lp64)

	# Avoid generating .eh_frame* sections.
	ifneq ($(CONFIG_UNWIND_TABLES),y)
	KBUILD_CFLAGS += -fno-asynchronous-unwind-tables -fno-unwind-tables
	KBUILD_AFLAGS += -fno-asynchronous-unwind-tables -fno-unwind-tables
	KBUILD_RUSTFLAGS += -Cforce-unwind-tables=n
	else
	KBUILD_CFLAGS += -fasynchronous-unwind-tables
	KBUILD_AFLAGS += -fasynchronous-unwind-tables
	KBUILD_RUSTFLAGS += -Cforce-unwind-tables=y -Zuse-sync-unwind=n
	endif

	ifeq ($(CONFIG_STACKPROTECTOR_PER_TASK),y)
	prepare: stack_protector_prepare
	stack_protector_prepare: prepare0
	$(eval KBUILD_CFLAGS += -mstack-protector-guard=sysreg \
	-mstack-protector-guard-reg=sp_el0 \
	-mstack-protector-guard-offset=$(shell \
	awk '{if ($$2 == "TSK_STACK_CANARY") print $$3;}' \
	include/generated/asm-offsets.h))
	endif

	ifeq ($(CONFIG_ARM64_BTI_KERNEL),y)
	KBUILD_CFLAGS += -mbranch-protection=pac-ret+bti
	KBUILD_RUSTFLAGS += -Zbranch-protection=bti,pac-ret
	else ifeq ($(CONFIG_ARM64_PTR_AUTH_KERNEL),y)
	KBUILD_RUSTFLAGS += -Zbranch-protection=pac-ret
	ifeq ($(CONFIG_CC_HAS_BRANCH_PROT_PAC_RET),y)
	KBUILD_CFLAGS += -mbranch-protection=pac-ret
	else
	KBUILD_CFLAGS += -msign-return-address=non-leaf
	endif
	else
	KBUILD_CFLAGS += $(call cc-option,-mbranch-protection=none)
	endif

	# Tell the assembler to support instructions from the latest target
	# architecture.
	#
	# For non-integrated assemblers we'll pass this on the command line, and for
	# integrated assemblers we'll define ARM64_ASM_ARCH and ARM64_ASM_PREAMBLE for
	# inline usage.
	#
	# We cannot pass the same arch flag to the compiler as this would allow it to
	# freely generate instructions which are not supported by earlier architecture
	# versions, which would prevent a single kernel image from working on earlier
	# hardware.
	ifeq ($(CONFIG_AS_HAS_ARMV8_5), y)
	asm-arch := armv8.5-a
	else ifeq ($(CONFIG_AS_HAS_ARMV8_4), y)
	asm-arch := armv8.4-a
	else ifeq ($(CONFIG_AS_HAS_ARMV8_3), y)
	asm-arch := armv8.3-a
	else ifeq ($(CONFIG_AS_HAS_ARMV8_2), y)
	asm-arch := armv8.2-a
	endif

	ifdef asm-arch
	KBUILD_CFLAGS += -Wa,-march=$(asm-arch) \
	-DARM64_ASM_ARCH='"$(asm-arch)"'
	endif

	ifeq ($(CONFIG_SHADOW_CALL_STACK), y)
	KBUILD_CFLAGS += -ffixed-x18
	KBUILD_RUSTFLAGS += -Zfixed-x18
	endif

	ifeq ($(CONFIG_CPU_BIG_ENDIAN), y)
	KBUILD_CPPFLAGS += -mbig-endian
	CHECKFLAGS += -D__AARCH64EB__
	# Prefer the baremetal ELF build target, but not all toolchains include
	# it so fall back to the standard linux version if needed.
	KBUILD_LDFLAGS += -EB $(call ld-option, -maarch64elfb, -maarch64linuxb -z norelro)
	UTS_MACHINE := aarch64_be
	else
	KBUILD_CPPFLAGS += -mlittle-endian
	CHECKFLAGS += -D__AARCH64EL__
	# Same as above, prefer ELF but fall back to linux target if needed.
	KBUILD_LDFLAGS += -EL $(call ld-option, -maarch64elf, -maarch64linux -z norelro)
	UTS_MACHINE := aarch64
	endif

	ifeq ($(CONFIG_LD_IS_LLD), y)
	KBUILD_LDFLAGS += -z norelro
	endif

	CHECKFLAGS += -D__aarch64__

	ifeq ($(CONFIG_DYNAMIC_FTRACE_WITH_CALL_OPS),y)
	KBUILD_CPPFLAGS += -DCC_USING_PATCHABLE_FUNCTION_ENTRY
	CC_FLAGS_FTRACE := -fpatchable-function-entry=4,2
	else ifeq ($(CONFIG_DYNAMIC_FTRACE_WITH_ARGS),y)
	KBUILD_CPPFLAGS += -DCC_USING_PATCHABLE_FUNCTION_ENTRY
	CC_FLAGS_FTRACE := -fpatchable-function-entry=2
	endif

	ifeq ($(CONFIG_KASAN_SW_TAGS), y)
	KASAN_SHADOW_SCALE_SHIFT := 4
	else ifeq ($(CONFIG_KASAN_GENERIC), y)
	KASAN_SHADOW_SCALE_SHIFT := 3
	endif

	KBUILD_CFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT)
	KBUILD_CPPFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT)
	KBUILD_AFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT)

	libs-y := arch/arm64/lib/ $(libs-y)
	libs-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a

	# Default target when executing plain make
	boot := arch/arm64/boot

	BOOT_TARGETS := Image vmlinuz.efi image.fit

	PHONY += $(BOOT_TARGETS)

	ifeq ($(CONFIG_EFI_ZBOOT),)
	KBUILD_IMAGE := $(boot)/Image.gz
	else
	KBUILD_IMAGE := $(boot)/vmlinuz.efi
	endif

	all: $(notdir $(KBUILD_IMAGE))

	image.fit: dtbs

	vmlinuz.efi image.fit: Image
	$(BOOT_TARGETS): vmlinux
	$(Q)$(MAKE) $(build)=$(boot) $(boot)/$@

	Image.%: Image
	$(Q)$(MAKE) $(build)=$(boot) $(boot)/$@

	ifeq ($(CONFIG_COMPRESSED_INSTALL),y)
	DEFAULT_KBUILD_IMAGE = $(KBUILD_IMAGE)
	else
	DEFAULT_KBUILD_IMAGE = $(boot)/Image
	endif

	install: KBUILD_IMAGE := $(DEFAULT_KBUILD_IMAGE)
	install zinstall:
	$(call cmd,install)

	archprepare:
	$(Q)$(MAKE) $(build)=arch/arm64/tools kapi
	ifeq ($(CONFIG_ARM64_ERRATUM_843419),y)
	ifneq ($(CONFIG_ARM64_LD_HAS_FIX_ERRATUM_843419),y)
	@echo "warning: ld does not support --fix-cortex-a53-843419; kernel may be susceptible to erratum" >&2
	endif
	endif
	ifeq ($(CONFIG_ARM64_USE_LSE_ATOMICS),y)
	ifneq ($(CONFIG_ARM64_LSE_ATOMICS),y)
	@echo "warning: LSE atomics not supported by binutils" >&2
	endif
	endif

	ifeq ($(KBUILD_EXTMOD),)
	# We need to generate vdso-offsets.h before compiling certain files in kernel/.
	# In order to do that, we should use the archprepare target, but we can't since
	# asm-offsets.h is included in some files used to generate vdso-offsets.h, and
	# asm-offsets.h is built in prepare0, for which archprepare is a dependency.
	# Therefore we need to generate the header after prepare0 has been made, hence
	# this hack.
	prepare: vdso_prepare
	vdso_prepare: prepare0
	$(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso \
	include/generated/vdso-offsets.h arch/arm64/kernel/vdso/vdso.so
	ifdef CONFIG_COMPAT_VDSO
	$(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso32 \
	arch/arm64/kernel/vdso32/vdso.so
	endif
	endif

	vdso-install-y += arch/arm64/kernel/vdso/vdso.so.dbg
	vdso-install-$(CONFIG_COMPAT_VDSO) += arch/arm64/kernel/vdso32/vdso32.so.dbg

	include $(srctree)/scripts/Makefile.defconf

	PHONY += virtconfig
	virtconfig:
	$(call merge_into_defconfig_override,defconfig,virt)

	define archhelp
	echo '* Image.gz - Compressed kernel image (arch/$(ARCH)/boot/Image.gz)'
	echo ' Image - Uncompressed kernel image (arch/$(ARCH)/boot/Image)'
	echo ' image.fit - Flat Image Tree (arch/$(ARCH)/boot/image.fit)'
	echo ' install - Install kernel (compressed if COMPRESSED_INSTALL set)'
	echo ' zinstall - Install compressed kernel'
	echo ' Install using (your) ~/bin/installkernel or'
	echo ' (distribution) /sbin/installkernel or'
	echo ' install to $$(INSTALL_PATH) and run lilo'
	endef