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. 80PACRET-y := pac-ret+leaf 81 82# Using a shadow call stack in leaf functions is too costly, so avoid PAC there 83# as well when we may be patching PAC into SCS 84PACRET-$(CONFIG_UNWIND_PATCH_PAC_INTO_SCS) := pac-ret 85 86ifeq ($(CONFIG_ARM64_BTI_KERNEL),y) 87branch-prot-flags-$(CONFIG_CC_HAS_BRANCH_PROT_PAC_RET_BTI) := -mbranch-protection=$(PACRET-y)+bti 88else 89branch-prot-flags-$(CONFIG_CC_HAS_BRANCH_PROT_PAC_RET) := -mbranch-protection=$(PACRET-y) 90endif 91# -march=armv8.3-a enables the non-nops instructions for PAC, to avoid the 92# compiler to generate them and consequently to break the single image contract 93# we pass it only to the assembler. This option is utilized only in case of non 94# integrated assemblers. 95ifeq ($(CONFIG_AS_HAS_PAC), y) 96asm-arch := armv8.3-a 97endif 98endif 99 100KBUILD_CFLAGS += $(branch-prot-flags-y) 101 102ifeq ($(CONFIG_AS_HAS_ARMV8_4), y) 103# make sure to pass the newest target architecture to -march. 104asm-arch := armv8.4-a 105endif 106 107ifeq ($(CONFIG_AS_HAS_ARMV8_5), y) 108# make sure to pass the newest target architecture to -march. 109asm-arch := armv8.5-a 110endif 111 112ifdef asm-arch 113KBUILD_CFLAGS += -Wa,-march=$(asm-arch) \ 114 -DARM64_ASM_ARCH='"$(asm-arch)"' 115endif 116 117ifeq ($(CONFIG_SHADOW_CALL_STACK), y) 118KBUILD_CFLAGS += -ffixed-x18 119endif 120 121ifeq ($(CONFIG_CPU_BIG_ENDIAN), y) 122KBUILD_CPPFLAGS += -mbig-endian 123CHECKFLAGS += -D__AARCH64EB__ 124# Prefer the baremetal ELF build target, but not all toolchains include 125# it so fall back to the standard linux version if needed. 126KBUILD_LDFLAGS += -EB $(call ld-option, -maarch64elfb, -maarch64linuxb -z norelro) 127UTS_MACHINE := aarch64_be 128else 129KBUILD_CPPFLAGS += -mlittle-endian 130CHECKFLAGS += -D__AARCH64EL__ 131# Same as above, prefer ELF but fall back to linux target if needed. 132KBUILD_LDFLAGS += -EL $(call ld-option, -maarch64elf, -maarch64linux -z norelro) 133UTS_MACHINE := aarch64 134endif 135 136ifeq ($(CONFIG_LD_IS_LLD), y) 137KBUILD_LDFLAGS += -z norelro 138endif 139 140CHECKFLAGS += -D__aarch64__ 141 142ifeq ($(CONFIG_DYNAMIC_FTRACE_WITH_ARGS),y) 143 KBUILD_CPPFLAGS += -DCC_USING_PATCHABLE_FUNCTION_ENTRY 144 CC_FLAGS_FTRACE := -fpatchable-function-entry=2 145endif 146 147ifeq ($(CONFIG_KASAN_SW_TAGS), y) 148KASAN_SHADOW_SCALE_SHIFT := 4 149else ifeq ($(CONFIG_KASAN_GENERIC), y) 150KASAN_SHADOW_SCALE_SHIFT := 3 151endif 152 153KBUILD_CFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT) 154KBUILD_CPPFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT) 155KBUILD_AFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT) 156 157libs-y := arch/arm64/lib/ $(libs-y) 158libs-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a 159 160# Default target when executing plain make 161boot := arch/arm64/boot 162 163ifeq ($(CONFIG_EFI_ZBOOT),) 164KBUILD_IMAGE := $(boot)/Image.gz 165else 166KBUILD_IMAGE := $(boot)/vmlinuz.efi 167endif 168 169all: $(notdir $(KBUILD_IMAGE)) 170 171 172Image vmlinuz.efi: vmlinux 173 $(Q)$(MAKE) $(build)=$(boot) $(boot)/$@ 174 175Image.%: Image 176 $(Q)$(MAKE) $(build)=$(boot) $(boot)/$@ 177 178install: KBUILD_IMAGE := $(boot)/Image 179install zinstall: 180 $(call cmd,install) 181 182PHONY += vdso_install 183vdso_install: 184 $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso $@ 185 $(if $(CONFIG_COMPAT_VDSO), \ 186 $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso32 $@) 187 188archprepare: 189 $(Q)$(MAKE) $(build)=arch/arm64/tools kapi 190ifeq ($(CONFIG_ARM64_ERRATUM_843419),y) 191 ifneq ($(CONFIG_ARM64_LD_HAS_FIX_ERRATUM_843419),y) 192 @echo "warning: ld does not support --fix-cortex-a53-843419; kernel may be susceptible to erratum" >&2 193 endif 194endif 195ifeq ($(CONFIG_ARM64_USE_LSE_ATOMICS),y) 196 ifneq ($(CONFIG_ARM64_LSE_ATOMICS),y) 197 @echo "warning: LSE atomics not supported by binutils" >&2 198 endif 199endif 200 201ifeq ($(KBUILD_EXTMOD),) 202# We need to generate vdso-offsets.h before compiling certain files in kernel/. 203# In order to do that, we should use the archprepare target, but we can't since 204# asm-offsets.h is included in some files used to generate vdso-offsets.h, and 205# asm-offsets.h is built in prepare0, for which archprepare is a dependency. 206# Therefore we need to generate the header after prepare0 has been made, hence 207# this hack. 208prepare: vdso_prepare 209vdso_prepare: prepare0 210 $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso \ 211 include/generated/vdso-offsets.h arch/arm64/kernel/vdso/vdso.so 212ifdef CONFIG_COMPAT_VDSO 213 $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso32 \ 214 include/generated/vdso32-offsets.h arch/arm64/kernel/vdso32/vdso.so 215endif 216endif 217 218define archhelp 219 echo '* Image.gz - Compressed kernel image (arch/$(ARCH)/boot/Image.gz)' 220 echo ' Image - Uncompressed kernel image (arch/$(ARCH)/boot/Image)' 221 echo ' install - Install uncompressed kernel' 222 echo ' zinstall - Install compressed kernel' 223 echo ' Install using (your) ~/bin/installkernel or' 224 echo ' (distribution) /sbin/installkernel or' 225 echo ' install to $$(INSTALL_PATH) and run lilo' 226endef 227