1# 2# arch/arm64/Makefile 3# 4# This file is included by the global makefile so that you can add your own 5# architecture-specific flags and dependencies. 6# 7# This file is subject to the terms and conditions of the GNU General Public 8# License. See the file "COPYING" in the main directory of this archive 9# for more details. 10# 11# Copyright (C) 1995-2001 by Russell King 12 13LDFLAGS_vmlinux :=--no-undefined -X 14 15ifeq ($(CONFIG_RELOCATABLE), y) 16# Pass --no-apply-dynamic-relocs to restore pre-binutils-2.27 behaviour 17# for relative relocs, since this leads to better Image compression 18# with the relocation offsets always being zero. 19LDFLAGS_vmlinux += -shared -Bsymbolic -z notext -z norelro \ 20 $(call ld-option, --no-apply-dynamic-relocs) 21endif 22 23ifeq ($(CONFIG_ARM64_ERRATUM_843419),y) 24 ifeq ($(call ld-option, --fix-cortex-a53-843419),) 25$(warning ld does not support --fix-cortex-a53-843419; kernel may be susceptible to erratum) 26 else 27LDFLAGS_vmlinux += --fix-cortex-a53-843419 28 endif 29endif 30 31# We never want expected sections to be placed heuristically by the 32# linker. All sections should be explicitly named in the linker script. 33LDFLAGS_vmlinux += $(call ld-option, --orphan-handling=warn) 34 35ifeq ($(CONFIG_ARM64_USE_LSE_ATOMICS), y) 36 ifneq ($(CONFIG_ARM64_LSE_ATOMICS), y) 37$(warning LSE atomics not supported by binutils) 38 endif 39endif 40 41cc_has_k_constraint := $(call try-run,echo \ 42 'int main(void) { \ 43 asm volatile("and w0, w0, %w0" :: "K" (4294967295)); \ 44 return 0; \ 45 }' | $(CC) -S -x c -o "$$TMP" -,,-DCONFIG_CC_HAS_K_CONSTRAINT=1) 46 47ifeq ($(CONFIG_BROKEN_GAS_INST),y) 48$(warning Detected assembler with broken .inst; disassembly will be unreliable) 49endif 50 51KBUILD_CFLAGS += -mgeneral-regs-only \ 52 $(compat_vdso) $(cc_has_k_constraint) 53KBUILD_CFLAGS += $(call cc-disable-warning, psabi) 54KBUILD_AFLAGS += $(compat_vdso) 55 56KBUILD_CFLAGS += $(call cc-option,-mabi=lp64) 57KBUILD_AFLAGS += $(call cc-option,-mabi=lp64) 58 59# Avoid generating .eh_frame* sections. 60KBUILD_CFLAGS += -fno-asynchronous-unwind-tables -fno-unwind-tables 61KBUILD_AFLAGS += -fno-asynchronous-unwind-tables -fno-unwind-tables 62 63ifeq ($(CONFIG_STACKPROTECTOR_PER_TASK),y) 64prepare: stack_protector_prepare 65stack_protector_prepare: prepare0 66 $(eval KBUILD_CFLAGS += -mstack-protector-guard=sysreg \ 67 -mstack-protector-guard-reg=sp_el0 \ 68 -mstack-protector-guard-offset=$(shell \ 69 awk '{if ($$2 == "TSK_STACK_CANARY") print $$3;}' \ 70 include/generated/asm-offsets.h)) 71endif 72 73# Ensure that if the compiler supports branch protection we default it 74# off, this will be overridden if we are using branch protection. 75branch-prot-flags-y += $(call cc-option,-mbranch-protection=none) 76 77ifeq ($(CONFIG_ARM64_PTR_AUTH),y) 78branch-prot-flags-$(CONFIG_CC_HAS_SIGN_RETURN_ADDRESS) := -msign-return-address=all 79# We enable additional protection for leaf functions as there is some 80# narrow potential for ROP protection benefits and no substantial 81# performance impact has been observed. 82ifeq ($(CONFIG_ARM64_BTI_KERNEL),y) 83branch-prot-flags-$(CONFIG_CC_HAS_BRANCH_PROT_PAC_RET_BTI) := -mbranch-protection=pac-ret+leaf+bti 84else 85branch-prot-flags-$(CONFIG_CC_HAS_BRANCH_PROT_PAC_RET) := -mbranch-protection=pac-ret+leaf 86endif 87# -march=armv8.3-a enables the non-nops instructions for PAC, to avoid the 88# compiler to generate them and consequently to break the single image contract 89# we pass it only to the assembler. This option is utilized only in case of non 90# integrated assemblers. 91ifeq ($(CONFIG_AS_HAS_PAC), y) 92asm-arch := armv8.3-a 93endif 94endif 95 96KBUILD_CFLAGS += $(branch-prot-flags-y) 97 98ifeq ($(CONFIG_AS_HAS_ARMV8_4), y) 99# make sure to pass the newest target architecture to -march. 100asm-arch := armv8.4-a 101endif 102 103ifdef asm-arch 104KBUILD_CFLAGS += -Wa,-march=$(asm-arch) \ 105 -DARM64_ASM_ARCH='"$(asm-arch)"' 106endif 107 108ifeq ($(CONFIG_SHADOW_CALL_STACK), y) 109KBUILD_CFLAGS += -ffixed-x18 110endif 111 112ifeq ($(CONFIG_CPU_BIG_ENDIAN), y) 113KBUILD_CPPFLAGS += -mbig-endian 114CHECKFLAGS += -D__AARCH64EB__ 115# Prefer the baremetal ELF build target, but not all toolchains include 116# it so fall back to the standard linux version if needed. 117KBUILD_LDFLAGS += -EB $(call ld-option, -maarch64elfb, -maarch64linuxb) 118UTS_MACHINE := aarch64_be 119else 120KBUILD_CPPFLAGS += -mlittle-endian 121CHECKFLAGS += -D__AARCH64EL__ 122# Same as above, prefer ELF but fall back to linux target if needed. 123KBUILD_LDFLAGS += -EL $(call ld-option, -maarch64elf, -maarch64linux) 124UTS_MACHINE := aarch64 125endif 126 127CHECKFLAGS += -D__aarch64__ 128 129ifeq ($(CONFIG_ARM64_MODULE_PLTS),y) 130KBUILD_LDS_MODULE += $(srctree)/arch/arm64/kernel/module.lds 131endif 132 133ifeq ($(CONFIG_DYNAMIC_FTRACE_WITH_REGS),y) 134 KBUILD_CPPFLAGS += -DCC_USING_PATCHABLE_FUNCTION_ENTRY 135 CC_FLAGS_FTRACE := -fpatchable-function-entry=2 136endif 137 138# Default value 139head-y := arch/arm64/kernel/head.o 140 141ifeq ($(CONFIG_KASAN_SW_TAGS), y) 142KASAN_SHADOW_SCALE_SHIFT := 4 143else 144KASAN_SHADOW_SCALE_SHIFT := 3 145endif 146 147KBUILD_CFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT) 148KBUILD_CPPFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT) 149KBUILD_AFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT) 150 151core-y += arch/arm64/ 152libs-y := arch/arm64/lib/ $(libs-y) 153libs-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a 154 155# Default target when executing plain make 156boot := arch/arm64/boot 157KBUILD_IMAGE := $(boot)/Image.gz 158 159all: Image.gz 160 161 162Image: vmlinux 163 $(Q)$(MAKE) $(build)=$(boot) $(boot)/$@ 164 165Image.%: Image 166 $(Q)$(MAKE) $(build)=$(boot) $(boot)/$@ 167 168zinstall install: 169 $(Q)$(MAKE) $(build)=$(boot) $@ 170 171PHONY += vdso_install 172vdso_install: 173 $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso $@ 174 $(if $(CONFIG_COMPAT_VDSO), \ 175 $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso32 $@) 176 177# We use MRPROPER_FILES and CLEAN_FILES now 178archclean: 179 $(Q)$(MAKE) $(clean)=$(boot) 180 181ifeq ($(KBUILD_EXTMOD),) 182# We need to generate vdso-offsets.h before compiling certain files in kernel/. 183# In order to do that, we should use the archprepare target, but we can't since 184# asm-offsets.h is included in some files used to generate vdso-offsets.h, and 185# asm-offsets.h is built in prepare0, for which archprepare is a dependency. 186# Therefore we need to generate the header after prepare0 has been made, hence 187# this hack. 188prepare: vdso_prepare 189vdso_prepare: prepare0 190 $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso include/generated/vdso-offsets.h 191 $(if $(CONFIG_COMPAT_VDSO),$(Q)$(MAKE) \ 192 $(build)=arch/arm64/kernel/vdso32 \ 193 include/generated/vdso32-offsets.h) 194endif 195 196define archhelp 197 echo '* Image.gz - Compressed kernel image (arch/$(ARCH)/boot/Image.gz)' 198 echo ' Image - Uncompressed kernel image (arch/$(ARCH)/boot/Image)' 199 echo ' install - Install uncompressed kernel' 200 echo ' zinstall - Install compressed kernel' 201 echo ' Install using (your) ~/bin/installkernel or' 202 echo ' (distribution) /sbin/installkernel or' 203 echo ' install to $$(INSTALL_PATH) and run lilo' 204endef 205