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 "$$TMP" -,,-DCONFIG_CC_HAS_K_CONSTRAINT=1) 34 35ifeq ($(CONFIG_BROKEN_GAS_INST),y) 36$(warning Detected assembler with broken .inst; disassembly will be unreliable) 37endif 38 39KBUILD_CFLAGS += -mgeneral-regs-only \ 40 $(compat_vdso) $(cc_has_k_constraint) 41KBUILD_CFLAGS += $(call cc-disable-warning, psabi) 42KBUILD_AFLAGS += $(compat_vdso) 43 44KBUILD_CFLAGS += $(call cc-option,-mabi=lp64) 45KBUILD_AFLAGS += $(call cc-option,-mabi=lp64) 46 47# Avoid generating .eh_frame* sections. 48KBUILD_CFLAGS += -fno-asynchronous-unwind-tables -fno-unwind-tables 49KBUILD_AFLAGS += -fno-asynchronous-unwind-tables -fno-unwind-tables 50 51ifeq ($(CONFIG_STACKPROTECTOR_PER_TASK),y) 52prepare: stack_protector_prepare 53stack_protector_prepare: prepare0 54 $(eval KBUILD_CFLAGS += -mstack-protector-guard=sysreg \ 55 -mstack-protector-guard-reg=sp_el0 \ 56 -mstack-protector-guard-offset=$(shell \ 57 awk '{if ($$2 == "TSK_STACK_CANARY") print $$3;}' \ 58 include/generated/asm-offsets.h)) 59endif 60 61ifeq ($(CONFIG_AS_HAS_ARMV8_2), y) 62# make sure to pass the newest target architecture to -march. 63asm-arch := armv8.2-a 64endif 65 66# Ensure that if the compiler supports branch protection we default it 67# off, this will be overridden if we are using branch protection. 68branch-prot-flags-y += $(call cc-option,-mbranch-protection=none) 69 70ifeq ($(CONFIG_ARM64_PTR_AUTH_KERNEL),y) 71branch-prot-flags-$(CONFIG_CC_HAS_SIGN_RETURN_ADDRESS) := -msign-return-address=all 72# We enable additional protection for leaf functions as there is some 73# narrow potential for ROP protection benefits and no substantial 74# performance impact has been observed. 75ifeq ($(CONFIG_ARM64_BTI_KERNEL),y) 76branch-prot-flags-$(CONFIG_CC_HAS_BRANCH_PROT_PAC_RET_BTI) := -mbranch-protection=pac-ret+leaf+bti 77else 78branch-prot-flags-$(CONFIG_CC_HAS_BRANCH_PROT_PAC_RET) := -mbranch-protection=pac-ret+leaf 79endif 80# -march=armv8.3-a enables the non-nops instructions for PAC, to avoid the 81# compiler to generate them and consequently to break the single image contract 82# we pass it only to the assembler. This option is utilized only in case of non 83# integrated assemblers. 84ifeq ($(CONFIG_AS_HAS_PAC), y) 85asm-arch := armv8.3-a 86endif 87endif 88 89KBUILD_CFLAGS += $(branch-prot-flags-y) 90 91ifeq ($(CONFIG_AS_HAS_ARMV8_4), y) 92# make sure to pass the newest target architecture to -march. 93asm-arch := armv8.4-a 94endif 95 96ifeq ($(CONFIG_AS_HAS_ARMV8_5), y) 97# make sure to pass the newest target architecture to -march. 98asm-arch := armv8.5-a 99endif 100 101ifdef asm-arch 102KBUILD_CFLAGS += -Wa,-march=$(asm-arch) \ 103 -DARM64_ASM_ARCH='"$(asm-arch)"' 104endif 105 106ifeq ($(CONFIG_SHADOW_CALL_STACK), y) 107KBUILD_CFLAGS += -ffixed-x18 108endif 109 110ifeq ($(CONFIG_CPU_BIG_ENDIAN), y) 111KBUILD_CPPFLAGS += -mbig-endian 112CHECKFLAGS += -D__AARCH64EB__ 113# Prefer the baremetal ELF build target, but not all toolchains include 114# it so fall back to the standard linux version if needed. 115KBUILD_LDFLAGS += -EB $(call ld-option, -maarch64elfb, -maarch64linuxb -z norelro) 116UTS_MACHINE := aarch64_be 117else 118KBUILD_CPPFLAGS += -mlittle-endian 119CHECKFLAGS += -D__AARCH64EL__ 120# Same as above, prefer ELF but fall back to linux target if needed. 121KBUILD_LDFLAGS += -EL $(call ld-option, -maarch64elf, -maarch64linux -z norelro) 122UTS_MACHINE := aarch64 123endif 124 125ifeq ($(CONFIG_LD_IS_LLD), y) 126KBUILD_LDFLAGS += -z norelro 127endif 128 129CHECKFLAGS += -D__aarch64__ 130 131ifeq ($(CONFIG_DYNAMIC_FTRACE_WITH_REGS),y) 132 KBUILD_CPPFLAGS += -DCC_USING_PATCHABLE_FUNCTION_ENTRY 133 CC_FLAGS_FTRACE := -fpatchable-function-entry=2 134endif 135 136# Default value 137head-y := arch/arm64/kernel/head.o 138 139ifeq ($(CONFIG_KASAN_SW_TAGS), y) 140KASAN_SHADOW_SCALE_SHIFT := 4 141else ifeq ($(CONFIG_KASAN_GENERIC), y) 142KASAN_SHADOW_SCALE_SHIFT := 3 143endif 144 145KBUILD_CFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT) 146KBUILD_CPPFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT) 147KBUILD_AFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT) 148 149libs-y := arch/arm64/lib/ $(libs-y) 150libs-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a 151 152# Default target when executing plain make 153boot := arch/arm64/boot 154KBUILD_IMAGE := $(boot)/Image.gz 155 156all: Image.gz 157 158 159Image: vmlinux 160 $(Q)$(MAKE) $(build)=$(boot) $(boot)/$@ 161 162Image.%: Image 163 $(Q)$(MAKE) $(build)=$(boot) $(boot)/$@ 164 165install: KBUILD_IMAGE := $(boot)/Image 166install zinstall: 167 $(call cmd,install) 168 169PHONY += vdso_install 170vdso_install: 171 $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso $@ 172 $(if $(CONFIG_COMPAT_VDSO), \ 173 $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso32 $@) 174 175archprepare: 176 $(Q)$(MAKE) $(build)=arch/arm64/tools kapi 177ifeq ($(CONFIG_ARM64_ERRATUM_843419),y) 178 ifneq ($(CONFIG_ARM64_LD_HAS_FIX_ERRATUM_843419),y) 179 @echo "warning: ld does not support --fix-cortex-a53-843419; kernel may be susceptible to erratum" >&2 180 endif 181endif 182ifeq ($(CONFIG_ARM64_USE_LSE_ATOMICS),y) 183 ifneq ($(CONFIG_ARM64_LSE_ATOMICS),y) 184 @echo "warning: LSE atomics not supported by binutils" >&2 185 endif 186endif 187 188ifeq ($(KBUILD_EXTMOD),) 189# We need to generate vdso-offsets.h before compiling certain files in kernel/. 190# In order to do that, we should use the archprepare target, but we can't since 191# asm-offsets.h is included in some files used to generate vdso-offsets.h, and 192# asm-offsets.h is built in prepare0, for which archprepare is a dependency. 193# Therefore we need to generate the header after prepare0 has been made, hence 194# this hack. 195prepare: vdso_prepare 196vdso_prepare: prepare0 197 $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso \ 198 include/generated/vdso-offsets.h arch/arm64/kernel/vdso/vdso.so 199ifdef CONFIG_COMPAT_VDSO 200 $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso32 \ 201 include/generated/vdso32-offsets.h arch/arm64/kernel/vdso32/vdso.so 202endif 203endif 204 205define archhelp 206 echo '* Image.gz - Compressed kernel image (arch/$(ARCH)/boot/Image.gz)' 207 echo ' Image - Uncompressed kernel image (arch/$(ARCH)/boot/Image)' 208 echo ' install - Install uncompressed kernel' 209 echo ' zinstall - Install compressed kernel' 210 echo ' Install using (your) ~/bin/installkernel or' 211 echo ' (distribution) /sbin/installkernel or' 212 echo ' install to $$(INSTALL_PATH) and run lilo' 213endef 214