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 14CPPFLAGS_vmlinux.lds = -DTEXT_OFFSET=$(TEXT_OFFSET) 15 16ifeq ($(CONFIG_RELOCATABLE), y) 17# Pass --no-apply-dynamic-relocs to restore pre-binutils-2.27 behaviour 18# for relative relocs, since this leads to better Image compression 19# with the relocation offsets always being zero. 20LDFLAGS_vmlinux += -shared -Bsymbolic -z notext -z norelro \ 21 $(call ld-option, --no-apply-dynamic-relocs) 22endif 23 24ifeq ($(CONFIG_ARM64_ERRATUM_843419),y) 25 ifeq ($(call ld-option, --fix-cortex-a53-843419),) 26$(warning ld does not support --fix-cortex-a53-843419; kernel may be susceptible to erratum) 27 else 28LDFLAGS_vmlinux += --fix-cortex-a53-843419 29 endif 30endif 31 32ifeq ($(CONFIG_ARM64_USE_LSE_ATOMICS), y) 33 ifneq ($(CONFIG_ARM64_LSE_ATOMICS), y) 34$(warning LSE atomics not supported by binutils) 35 endif 36endif 37 38cc_has_k_constraint := $(call try-run,echo \ 39 'int main(void) { \ 40 asm volatile("and w0, w0, %w0" :: "K" (4294967295)); \ 41 return 0; \ 42 }' | $(CC) -S -x c -o "$$TMP" -,,-DCONFIG_CC_HAS_K_CONSTRAINT=1) 43 44ifeq ($(CONFIG_BROKEN_GAS_INST),y) 45$(warning Detected assembler with broken .inst; disassembly will be unreliable) 46endif 47 48KBUILD_CFLAGS += -mgeneral-regs-only \ 49 $(compat_vdso) $(cc_has_k_constraint) 50KBUILD_CFLAGS += -fno-asynchronous-unwind-tables 51KBUILD_CFLAGS += $(call cc-disable-warning, psabi) 52KBUILD_AFLAGS += $(compat_vdso) 53 54KBUILD_CFLAGS += $(call cc-option,-mabi=lp64) 55KBUILD_AFLAGS += $(call cc-option,-mabi=lp64) 56 57ifeq ($(CONFIG_STACKPROTECTOR_PER_TASK),y) 58prepare: stack_protector_prepare 59stack_protector_prepare: prepare0 60 $(eval KBUILD_CFLAGS += -mstack-protector-guard=sysreg \ 61 -mstack-protector-guard-reg=sp_el0 \ 62 -mstack-protector-guard-offset=$(shell \ 63 awk '{if ($$2 == "TSK_STACK_CANARY") print $$3;}' \ 64 include/generated/asm-offsets.h)) 65endif 66 67# Ensure that if the compiler supports branch protection we default it 68# off, this will be overridden if we are using branch protection. 69branch-prot-flags-y += $(call cc-option,-mbranch-protection=none) 70 71ifeq ($(CONFIG_ARM64_PTR_AUTH),y) 72branch-prot-flags-$(CONFIG_CC_HAS_SIGN_RETURN_ADDRESS) := -msign-return-address=all 73# We enable additional protection for leaf functions as there is some 74# narrow potential for ROP protection benefits and no substantial 75# performance impact has been observed. 76ifeq ($(CONFIG_ARM64_BTI_KERNEL),y) 77branch-prot-flags-$(CONFIG_CC_HAS_BRANCH_PROT_PAC_RET_BTI) := -mbranch-protection=pac-ret+leaf+bti 78else 79branch-prot-flags-$(CONFIG_CC_HAS_BRANCH_PROT_PAC_RET) := -mbranch-protection=pac-ret+leaf 80endif 81# -march=armv8.3-a enables the non-nops instructions for PAC, to avoid the 82# compiler to generate them and consequently to break the single image contract 83# we pass it only to the assembler. This option is utilized only in case of non 84# integrated assemblers. 85ifeq ($(CONFIG_AS_HAS_PAC), y) 86asm-arch := armv8.3-a 87endif 88endif 89 90KBUILD_CFLAGS += $(branch-prot-flags-y) 91 92ifeq ($(CONFIG_AS_HAS_ARMV8_4), y) 93# make sure to pass the newest target architecture to -march. 94asm-arch := armv8.4-a 95endif 96 97ifdef asm-arch 98KBUILD_CFLAGS += -Wa,-march=$(asm-arch) \ 99 -DARM64_ASM_ARCH='"$(asm-arch)"' 100endif 101 102ifeq ($(CONFIG_SHADOW_CALL_STACK), y) 103KBUILD_CFLAGS += -ffixed-x18 104endif 105 106ifeq ($(CONFIG_CPU_BIG_ENDIAN), y) 107KBUILD_CPPFLAGS += -mbig-endian 108CHECKFLAGS += -D__AARCH64EB__ 109# Prefer the baremetal ELF build target, but not all toolchains include 110# it so fall back to the standard linux version if needed. 111KBUILD_LDFLAGS += -EB $(call ld-option, -maarch64elfb, -maarch64linuxb) 112UTS_MACHINE := aarch64_be 113else 114KBUILD_CPPFLAGS += -mlittle-endian 115CHECKFLAGS += -D__AARCH64EL__ 116# Same as above, prefer ELF but fall back to linux target if needed. 117KBUILD_LDFLAGS += -EL $(call ld-option, -maarch64elf, -maarch64linux) 118UTS_MACHINE := aarch64 119endif 120 121CHECKFLAGS += -D__aarch64__ 122 123ifeq ($(CONFIG_ARM64_MODULE_PLTS),y) 124KBUILD_LDS_MODULE += $(srctree)/arch/arm64/kernel/module.lds 125endif 126 127ifeq ($(CONFIG_DYNAMIC_FTRACE_WITH_REGS),y) 128 KBUILD_CPPFLAGS += -DCC_USING_PATCHABLE_FUNCTION_ENTRY 129 CC_FLAGS_FTRACE := -fpatchable-function-entry=2 130endif 131 132# Default value 133head-y := arch/arm64/kernel/head.o 134 135# The byte offset of the kernel image in RAM from the start of RAM. 136TEXT_OFFSET := 0x0 137 138ifeq ($(CONFIG_KASAN_SW_TAGS), y) 139KASAN_SHADOW_SCALE_SHIFT := 4 140else 141KASAN_SHADOW_SCALE_SHIFT := 3 142endif 143 144KBUILD_CFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT) 145KBUILD_CPPFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT) 146KBUILD_AFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT) 147 148export TEXT_OFFSET 149 150core-y += arch/arm64/ 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 156KBUILD_IMAGE := $(boot)/Image.gz 157 158all: Image.gz 159 160 161Image: vmlinux 162 $(Q)$(MAKE) $(build)=$(boot) $(boot)/$@ 163 164Image.%: Image 165 $(Q)$(MAKE) $(build)=$(boot) $(boot)/$@ 166 167zinstall install: 168 $(Q)$(MAKE) $(build)=$(boot) $@ 169 170PHONY += vdso_install 171vdso_install: 172 $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso $@ 173 $(if $(CONFIG_COMPAT_VDSO), \ 174 $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso32 $@) 175 176# We use MRPROPER_FILES and CLEAN_FILES now 177archclean: 178 $(Q)$(MAKE) $(clean)=$(boot) 179 180ifeq ($(KBUILD_EXTMOD),) 181# We need to generate vdso-offsets.h before compiling certain files in kernel/. 182# In order to do that, we should use the archprepare target, but we can't since 183# asm-offsets.h is included in some files used to generate vdso-offsets.h, and 184# asm-offsets.h is built in prepare0, for which archprepare is a dependency. 185# Therefore we need to generate the header after prepare0 has been made, hence 186# this hack. 187prepare: vdso_prepare 188vdso_prepare: prepare0 189 $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso include/generated/vdso-offsets.h 190 $(if $(CONFIG_COMPAT_VDSO),$(Q)$(MAKE) \ 191 $(build)=arch/arm64/kernel/vdso32 \ 192 include/generated/vdso32-offsets.h) 193endif 194 195define archhelp 196 echo '* Image.gz - Compressed kernel image (arch/$(ARCH)/boot/Image.gz)' 197 echo ' Image - Uncompressed kernel image (arch/$(ARCH)/boot/Image)' 198 echo ' install - Install uncompressed kernel' 199 echo ' zinstall - Install compressed kernel' 200 echo ' Install using (your) ~/bin/installkernel or' 201 echo ' (distribution) /sbin/installkernel or' 202 echo ' install to $$(INSTALL_PATH) and run lilo' 203endef 204