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 \ 20 $(call ld-option, --no-apply-dynamic-relocs) 21endif 22 23ifeq ($(CONFIG_ARM64_ERRATUM_843419),y) 24 ifeq ($(CONFIG_ARM64_LD_HAS_FIX_ERRATUM_843419),y) 25LDFLAGS_vmlinux += --fix-cortex-a53-843419 26 endif 27endif 28 29cc_has_k_constraint := $(call try-run,echo \ 30 'int main(void) { \ 31 asm volatile("and w0, w0, %w0" :: "K" (4294967295)); \ 32 return 0; \ 33 }' | $(CC) -S -x c -o "$$TMP" -,,-DCONFIG_CC_HAS_K_CONSTRAINT=1) 34 35ifeq ($(CONFIG_BROKEN_GAS_INST),y) 36$(warning Detected assembler with broken .inst; disassembly will be unreliable) 37endif 38 39KBUILD_CFLAGS += -mgeneral-regs-only \ 40 $(compat_vdso) $(cc_has_k_constraint) 41KBUILD_CFLAGS += $(call cc-disable-warning, psabi) 42KBUILD_AFLAGS += $(compat_vdso) 43 44KBUILD_CFLAGS += $(call cc-option,-mabi=lp64) 45KBUILD_AFLAGS += $(call cc-option,-mabi=lp64) 46 47# Avoid generating .eh_frame* sections. 48ifneq ($(CONFIG_UNWIND_TABLES),y) 49KBUILD_CFLAGS += -fno-asynchronous-unwind-tables -fno-unwind-tables 50KBUILD_AFLAGS += -fno-asynchronous-unwind-tables -fno-unwind-tables 51else 52KBUILD_CFLAGS += -fasynchronous-unwind-tables 53KBUILD_AFLAGS += -fasynchronous-unwind-tables 54endif 55 56ifeq ($(CONFIG_STACKPROTECTOR_PER_TASK),y) 57prepare: stack_protector_prepare 58stack_protector_prepare: prepare0 59 $(eval KBUILD_CFLAGS += -mstack-protector-guard=sysreg \ 60 -mstack-protector-guard-reg=sp_el0 \ 61 -mstack-protector-guard-offset=$(shell \ 62 awk '{if ($$2 == "TSK_STACK_CANARY") print $$3;}' \ 63 include/generated/asm-offsets.h)) 64endif 65 66ifeq ($(CONFIG_AS_HAS_ARMV8_2), y) 67# make sure to pass the newest target architecture to -march. 68asm-arch := armv8.2-a 69endif 70 71# Ensure that if the compiler supports branch protection we default it 72# off, this will be overridden if we are using branch protection. 73branch-prot-flags-y += $(call cc-option,-mbranch-protection=none) 74 75ifeq ($(CONFIG_ARM64_PTR_AUTH_KERNEL),y) 76branch-prot-flags-$(CONFIG_CC_HAS_SIGN_RETURN_ADDRESS) := -msign-return-address=all 77# We enable additional protection for leaf functions as there is some 78# narrow potential for ROP protection benefits and no substantial 79# performance impact has been observed. 80ifeq ($(CONFIG_ARM64_BTI_KERNEL),y) 81branch-prot-flags-$(CONFIG_CC_HAS_BRANCH_PROT_PAC_RET_BTI) := -mbranch-protection=pac-ret+leaf+bti 82else 83branch-prot-flags-$(CONFIG_CC_HAS_BRANCH_PROT_PAC_RET) := -mbranch-protection=pac-ret+leaf 84endif 85# -march=armv8.3-a enables the non-nops instructions for PAC, to avoid the 86# compiler to generate them and consequently to break the single image contract 87# we pass it only to the assembler. This option is utilized only in case of non 88# integrated assemblers. 89ifeq ($(CONFIG_AS_HAS_PAC), y) 90asm-arch := armv8.3-a 91endif 92endif 93 94KBUILD_CFLAGS += $(branch-prot-flags-y) 95 96ifeq ($(CONFIG_AS_HAS_ARMV8_4), y) 97# make sure to pass the newest target architecture to -march. 98asm-arch := armv8.4-a 99endif 100 101ifeq ($(CONFIG_AS_HAS_ARMV8_5), y) 102# make sure to pass the newest target architecture to -march. 103asm-arch := armv8.5-a 104endif 105 106ifdef asm-arch 107KBUILD_CFLAGS += -Wa,-march=$(asm-arch) \ 108 -DARM64_ASM_ARCH='"$(asm-arch)"' 109endif 110 111ifeq ($(CONFIG_SHADOW_CALL_STACK), y) 112KBUILD_CFLAGS += -ffixed-x18 113endif 114 115ifeq ($(CONFIG_CPU_BIG_ENDIAN), y) 116KBUILD_CPPFLAGS += -mbig-endian 117CHECKFLAGS += -D__AARCH64EB__ 118# Prefer the baremetal ELF build target, but not all toolchains include 119# it so fall back to the standard linux version if needed. 120KBUILD_LDFLAGS += -EB $(call ld-option, -maarch64elfb, -maarch64linuxb -z norelro) 121UTS_MACHINE := aarch64_be 122else 123KBUILD_CPPFLAGS += -mlittle-endian 124CHECKFLAGS += -D__AARCH64EL__ 125# Same as above, prefer ELF but fall back to linux target if needed. 126KBUILD_LDFLAGS += -EL $(call ld-option, -maarch64elf, -maarch64linux -z norelro) 127UTS_MACHINE := aarch64 128endif 129 130ifeq ($(CONFIG_LD_IS_LLD), y) 131KBUILD_LDFLAGS += -z norelro 132endif 133 134CHECKFLAGS += -D__aarch64__ 135 136ifeq ($(CONFIG_DYNAMIC_FTRACE_WITH_REGS),y) 137 KBUILD_CPPFLAGS += -DCC_USING_PATCHABLE_FUNCTION_ENTRY 138 CC_FLAGS_FTRACE := -fpatchable-function-entry=2 139endif 140 141ifeq ($(CONFIG_KASAN_SW_TAGS), y) 142KASAN_SHADOW_SCALE_SHIFT := 4 143else ifeq ($(CONFIG_KASAN_GENERIC), y) 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 151libs-y := arch/arm64/lib/ $(libs-y) 152libs-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a 153 154# Default target when executing plain make 155boot := arch/arm64/boot 156 157ifeq ($(CONFIG_EFI_ZBOOT),) 158KBUILD_IMAGE := $(boot)/Image.gz 159else 160KBUILD_IMAGE := $(boot)/vmlinuz.efi 161endif 162 163all: $(notdir $(KBUILD_IMAGE)) 164 165 166Image vmlinuz.efi: vmlinux 167 $(Q)$(MAKE) $(build)=$(boot) $(boot)/$@ 168 169Image.%: Image 170 $(Q)$(MAKE) $(build)=$(boot) $(boot)/$@ 171 172install: KBUILD_IMAGE := $(boot)/Image 173install zinstall: 174 $(call cmd,install) 175 176PHONY += vdso_install 177vdso_install: 178 $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso $@ 179 $(if $(CONFIG_COMPAT_VDSO), \ 180 $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso32 $@) 181 182archprepare: 183 $(Q)$(MAKE) $(build)=arch/arm64/tools kapi 184ifeq ($(CONFIG_ARM64_ERRATUM_843419),y) 185 ifneq ($(CONFIG_ARM64_LD_HAS_FIX_ERRATUM_843419),y) 186 @echo "warning: ld does not support --fix-cortex-a53-843419; kernel may be susceptible to erratum" >&2 187 endif 188endif 189ifeq ($(CONFIG_ARM64_USE_LSE_ATOMICS),y) 190 ifneq ($(CONFIG_ARM64_LSE_ATOMICS),y) 191 @echo "warning: LSE atomics not supported by binutils" >&2 192 endif 193endif 194 195ifeq ($(KBUILD_EXTMOD),) 196# We need to generate vdso-offsets.h before compiling certain files in kernel/. 197# In order to do that, we should use the archprepare target, but we can't since 198# asm-offsets.h is included in some files used to generate vdso-offsets.h, and 199# asm-offsets.h is built in prepare0, for which archprepare is a dependency. 200# Therefore we need to generate the header after prepare0 has been made, hence 201# this hack. 202prepare: vdso_prepare 203vdso_prepare: prepare0 204 $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso \ 205 include/generated/vdso-offsets.h arch/arm64/kernel/vdso/vdso.so 206ifdef CONFIG_COMPAT_VDSO 207 $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso32 \ 208 include/generated/vdso32-offsets.h arch/arm64/kernel/vdso32/vdso.so 209endif 210endif 211 212define archhelp 213 echo '* Image.gz - Compressed kernel image (arch/$(ARCH)/boot/Image.gz)' 214 echo ' Image - Uncompressed kernel image (arch/$(ARCH)/boot/Image)' 215 echo ' install - Install uncompressed kernel' 216 echo ' zinstall - Install compressed kernel' 217 echo ' Install using (your) ~/bin/installkernel or' 218 echo ' (distribution) /sbin/installkernel or' 219 echo ' install to $$(INSTALL_PATH) and run lilo' 220endef 221