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=$(TEXT_OFFSET) 15GZFLAGS :=-9 16 17ifeq ($(CONFIG_RELOCATABLE), y) 18# Pass --no-apply-dynamic-relocs to restore pre-binutils-2.27 behaviour 19# for relative relocs, since this leads to better Image compression 20# with the relocation offsets always being zero. 21LDFLAGS_vmlinux += -shared -Bsymbolic -z notext \ 22 $(call ld-option, --no-apply-dynamic-relocs) 23endif 24 25ifeq ($(CONFIG_ARM64_ERRATUM_843419),y) 26 ifeq ($(call ld-option, --fix-cortex-a53-843419),) 27$(warning ld does not support --fix-cortex-a53-843419; kernel may be susceptible to erratum) 28 else 29LDFLAGS_vmlinux += --fix-cortex-a53-843419 30 endif 31endif 32 33# Check for binutils support for specific extensions 34lseinstr := $(call as-instr,.arch_extension lse,-DCONFIG_AS_LSE=1) 35 36ifeq ($(CONFIG_ARM64_LSE_ATOMICS), y) 37 ifeq ($(lseinstr),) 38$(warning LSE atomics not supported by binutils) 39 endif 40endif 41 42cc_has_k_constraint := $(call try-run,echo \ 43 'int main(void) { \ 44 asm volatile("and w0, w0, %w0" :: "K" (4294967295)); \ 45 return 0; \ 46 }' | $(CC) -S -x c -o "$$TMP" -,,-DCONFIG_CC_HAS_K_CONSTRAINT=1) 47 48ifeq ($(CONFIG_ARM64), y) 49brokengasinst := $(call as-instr,1:\n.inst 0\n.rept . - 1b\n\nnop\n.endr\n,,-DCONFIG_BROKEN_GAS_INST=1) 50 51 ifneq ($(brokengasinst),) 52$(warning Detected assembler with broken .inst; disassembly will be unreliable) 53 endif 54endif 55 56KBUILD_CFLAGS += -mgeneral-regs-only $(lseinstr) $(brokengasinst) \ 57 $(compat_vdso) $(cc_has_k_constraint) 58KBUILD_CFLAGS += -fno-asynchronous-unwind-tables 59KBUILD_CFLAGS += $(call cc-disable-warning, psabi) 60KBUILD_AFLAGS += $(lseinstr) $(brokengasinst) $(compat_vdso) 61 62KBUILD_CFLAGS += $(call cc-option,-mabi=lp64) 63KBUILD_AFLAGS += $(call cc-option,-mabi=lp64) 64 65ifeq ($(CONFIG_STACKPROTECTOR_PER_TASK),y) 66prepare: stack_protector_prepare 67stack_protector_prepare: prepare0 68 $(eval KBUILD_CFLAGS += -mstack-protector-guard=sysreg \ 69 -mstack-protector-guard-reg=sp_el0 \ 70 -mstack-protector-guard-offset=$(shell \ 71 awk '{if ($$2 == "TSK_STACK_CANARY") print $$3;}' \ 72 include/generated/asm-offsets.h)) 73endif 74 75# Ensure that if the compiler supports branch protection we default it 76# off. 77KBUILD_CFLAGS += $(call cc-option,-mbranch-protection=none) 78 79ifeq ($(CONFIG_SHADOW_CALL_STACK), y) 80KBUILD_CFLAGS += -ffixed-x18 81endif 82 83ifeq ($(CONFIG_CPU_BIG_ENDIAN), y) 84KBUILD_CPPFLAGS += -mbig-endian 85CHECKFLAGS += -D__AARCH64EB__ 86AS += -EB 87# Prefer the baremetal ELF build target, but not all toolchains include 88# it so fall back to the standard linux version if needed. 89KBUILD_LDFLAGS += -EB $(call ld-option, -maarch64elfb, -maarch64linuxb -z norelro) 90UTS_MACHINE := aarch64_be 91else 92KBUILD_CPPFLAGS += -mlittle-endian 93CHECKFLAGS += -D__AARCH64EL__ 94AS += -EL 95# Same as above, prefer ELF but fall back to linux target if needed. 96KBUILD_LDFLAGS += -EL $(call ld-option, -maarch64elf, -maarch64linux -z norelro) 97UTS_MACHINE := aarch64 98endif 99 100ifeq ($(CONFIG_LD_IS_LLD), y) 101KBUILD_LDFLAGS += -z norelro 102endif 103 104CHECKFLAGS += -D__aarch64__ 105 106ifeq ($(CONFIG_ARM64_MODULE_PLTS),y) 107KBUILD_LDS_MODULE += $(srctree)/arch/arm64/kernel/module.lds 108endif 109 110# Default value 111head-y := arch/arm64/kernel/head.o 112 113# The byte offset of the kernel image in RAM from the start of RAM. 114ifeq ($(CONFIG_ARM64_RANDOMIZE_TEXT_OFFSET), y) 115TEXT_OFFSET := $(shell awk "BEGIN {srand(); printf \"0x%06x\n\", \ 116 int(2 * 1024 * 1024 / (2 ^ $(CONFIG_ARM64_PAGE_SHIFT)) * \ 117 rand()) * (2 ^ $(CONFIG_ARM64_PAGE_SHIFT))}") 118else 119TEXT_OFFSET := 0x00080000 120endif 121 122ifeq ($(CONFIG_KASAN_SW_TAGS), y) 123KASAN_SHADOW_SCALE_SHIFT := 4 124else 125KASAN_SHADOW_SCALE_SHIFT := 3 126endif 127 128KBUILD_CFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT) 129KBUILD_CPPFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT) 130KBUILD_AFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT) 131 132export TEXT_OFFSET GZFLAGS 133 134core-y += arch/arm64/ 135libs-y := arch/arm64/lib/ $(libs-y) 136core-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a 137 138# Default target when executing plain make 139boot := arch/arm64/boot 140KBUILD_IMAGE := $(boot)/Image.gz 141 142all: Image.gz 143 144 145Image: vmlinux 146 $(Q)$(MAKE) $(build)=$(boot) $(boot)/$@ 147 148Image.%: Image 149 $(Q)$(MAKE) $(build)=$(boot) $(boot)/$@ 150 151zinstall install: 152 $(Q)$(MAKE) $(build)=$(boot) $@ 153 154PHONY += vdso_install 155vdso_install: 156 $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso $@ 157 $(if $(CONFIG_COMPAT_VDSO), \ 158 $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso32 $@) 159 160# We use MRPROPER_FILES and CLEAN_FILES now 161archclean: 162 $(Q)$(MAKE) $(clean)=$(boot) 163 164ifeq ($(KBUILD_EXTMOD),) 165# We need to generate vdso-offsets.h before compiling certain files in kernel/. 166# In order to do that, we should use the archprepare target, but we can't since 167# asm-offsets.h is included in some files used to generate vdso-offsets.h, and 168# asm-offsets.h is built in prepare0, for which archprepare is a dependency. 169# Therefore we need to generate the header after prepare0 has been made, hence 170# this hack. 171prepare: vdso_prepare 172vdso_prepare: prepare0 173 $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso include/generated/vdso-offsets.h 174 $(if $(CONFIG_COMPAT_VDSO),$(Q)$(MAKE) \ 175 $(build)=arch/arm64/kernel/vdso32 \ 176 include/generated/vdso32-offsets.h) 177endif 178 179define archhelp 180 echo '* Image.gz - Compressed kernel image (arch/$(ARCH)/boot/Image.gz)' 181 echo ' Image - Uncompressed kernel image (arch/$(ARCH)/boot/Image)' 182 echo ' install - Install uncompressed kernel' 183 echo ' zinstall - Install compressed kernel' 184 echo ' Install using (your) ~/bin/installkernel or' 185 echo ' (distribution) /sbin/installkernel or' 186 echo ' install to $$(INSTALL_PATH) and run lilo' 187endef 188