LXR linux/arch/arm64/Makefile

   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 -z norelro
  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 ($(call ld-option, --fix-cortex-a53-843419),)
  25$(warning ld does not support --fix-cortex-a53-843419; kernel may be susceptible to erratum)
  26  else
  27LDFLAGS_vmlinux += --fix-cortex-a53-843419
  28  endif
  29endif
  30
  31ifeq ($(CONFIG_ARM64_USE_LSE_ATOMICS), y)
  32  ifneq ($(CONFIG_ARM64_LSE_ATOMICS), y)
  33$(warning LSE atomics not supported by binutils)
  34  endif
  35endif
  36
  37cc_has_k_constraint := $(call try-run,echo                              \
  38        'int main(void) {                                               \
  39                asm volatile("and w0, w0, %w0" :: "K" (4294967295));    \
  40                return 0;                                               \
  41        }' | $(CC) -S -x c -o "$$TMP" -,,-DCONFIG_CC_HAS_K_CONSTRAINT=1)
  42
  43ifeq ($(CONFIG_BROKEN_GAS_INST),y)
  44$(warning Detected assembler with broken .inst; disassembly will be unreliable)
  45endif
  46
  47KBUILD_CFLAGS   += -mgeneral-regs-only  \
  48                   $(compat_vdso) $(cc_has_k_constraint)
  49KBUILD_CFLAGS   += $(call cc-disable-warning, psabi)
  50KBUILD_AFLAGS   += $(compat_vdso)
  51
  52KBUILD_CFLAGS   += $(call cc-option,-mabi=lp64)
  53KBUILD_AFLAGS   += $(call cc-option,-mabi=lp64)
  54
  55# Avoid generating .eh_frame* sections.
  56KBUILD_CFLAGS   += -fno-asynchronous-unwind-tables -fno-unwind-tables
  57KBUILD_AFLAGS   += -fno-asynchronous-unwind-tables -fno-unwind-tables
  58
  59ifeq ($(CONFIG_STACKPROTECTOR_PER_TASK),y)
  60prepare: stack_protector_prepare
  61stack_protector_prepare: prepare0
  62        $(eval KBUILD_CFLAGS += -mstack-protector-guard=sysreg            \
  63                                -mstack-protector-guard-reg=sp_el0        \
  64                                -mstack-protector-guard-offset=$(shell    \
  65                        awk '{if ($$2 == "TSK_STACK_CANARY") print $$3;}' \
  66                                        include/generated/asm-offsets.h))
  67endif
  68
  69# Ensure that if the compiler supports branch protection we default it
  70# off, this will be overridden if we are using branch protection.
  71branch-prot-flags-y += $(call cc-option,-mbranch-protection=none)
  72
  73ifeq ($(CONFIG_ARM64_PTR_AUTH),y)
  74branch-prot-flags-$(CONFIG_CC_HAS_SIGN_RETURN_ADDRESS) := -msign-return-address=all
  75# We enable additional protection for leaf functions as there is some
  76# narrow potential for ROP protection benefits and no substantial
  77# performance impact has been observed.
  78ifeq ($(CONFIG_ARM64_BTI_KERNEL),y)
  79branch-prot-flags-$(CONFIG_CC_HAS_BRANCH_PROT_PAC_RET_BTI) := -mbranch-protection=pac-ret+leaf+bti
  80else
  81branch-prot-flags-$(CONFIG_CC_HAS_BRANCH_PROT_PAC_RET) := -mbranch-protection=pac-ret+leaf
  82endif
  83# -march=armv8.3-a enables the non-nops instructions for PAC, to avoid the
  84# compiler to generate them and consequently to break the single image contract
  85# we pass it only to the assembler. This option is utilized only in case of non
  86# integrated assemblers.
  87ifeq ($(CONFIG_AS_HAS_PAC), y)
  88asm-arch := armv8.3-a
  89endif
  90endif
  91
  92KBUILD_CFLAGS += $(branch-prot-flags-y)
  93
  94ifeq ($(CONFIG_AS_HAS_ARMV8_4), y)
  95# make sure to pass the newest target architecture to -march.
  96asm-arch := armv8.4-a
  97endif
  98
  99ifdef asm-arch
 100KBUILD_CFLAGS   += -Wa,-march=$(asm-arch) \
 101                   -DARM64_ASM_ARCH='"$(asm-arch)"'
 102endif
 103
 104ifeq ($(CONFIG_SHADOW_CALL_STACK), y)
 105KBUILD_CFLAGS   += -ffixed-x18
 106endif
 107
 108ifeq ($(CONFIG_CPU_BIG_ENDIAN), y)
 109KBUILD_CPPFLAGS += -mbig-endian
 110CHECKFLAGS      += -D__AARCH64EB__
 111# Prefer the baremetal ELF build target, but not all toolchains include
 112# it so fall back to the standard linux version if needed.
 113KBUILD_LDFLAGS  += -EB $(call ld-option, -maarch64elfb, -maarch64linuxb)
 114UTS_MACHINE     := aarch64_be
 115else
 116KBUILD_CPPFLAGS += -mlittle-endian
 117CHECKFLAGS      += -D__AARCH64EL__
 118# Same as above, prefer ELF but fall back to linux target if needed.
 119KBUILD_LDFLAGS  += -EL $(call ld-option, -maarch64elf, -maarch64linux)
 120UTS_MACHINE     := aarch64
 121endif
 122
 123CHECKFLAGS      += -D__aarch64__
 124
 125ifeq ($(CONFIG_DYNAMIC_FTRACE_WITH_REGS),y)
 126  KBUILD_CPPFLAGS += -DCC_USING_PATCHABLE_FUNCTION_ENTRY
 127  CC_FLAGS_FTRACE := -fpatchable-function-entry=2
 128endif
 129
 130# Default value
 131head-y          := arch/arm64/kernel/head.o
 132
 133ifeq ($(CONFIG_KASAN_SW_TAGS), y)
 134KASAN_SHADOW_SCALE_SHIFT := 4
 135else
 136KASAN_SHADOW_SCALE_SHIFT := 3
 137endif
 138
 139KBUILD_CFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT)
 140KBUILD_CPPFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT)
 141KBUILD_AFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT)
 142
 143core-y          += arch/arm64/
 144libs-y          := arch/arm64/lib/ $(libs-y)
 145libs-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a
 146
 147# Default target when executing plain make
 148boot            := arch/arm64/boot
 149KBUILD_IMAGE    := $(boot)/Image.gz
 150
 151all:    Image.gz
 152
 153
 154Image: vmlinux
 155        $(Q)$(MAKE) $(build)=$(boot) $(boot)/$@
 156
 157Image.%: Image
 158        $(Q)$(MAKE) $(build)=$(boot) $(boot)/$@
 159
 160zinstall install:
 161        $(Q)$(MAKE) $(build)=$(boot) $@
 162
 163PHONY += vdso_install
 164vdso_install:
 165        $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso $@
 166        $(if $(CONFIG_COMPAT_VDSO), \
 167                $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso32 $@)
 168
 169# We use MRPROPER_FILES and CLEAN_FILES now
 170archclean:
 171        $(Q)$(MAKE) $(clean)=$(boot)
 172
 173ifeq ($(KBUILD_EXTMOD),)
 174# We need to generate vdso-offsets.h before compiling certain files in kernel/.
 175# In order to do that, we should use the archprepare target, but we can't since
 176# asm-offsets.h is included in some files used to generate vdso-offsets.h, and
 177# asm-offsets.h is built in prepare0, for which archprepare is a dependency.
 178# Therefore we need to generate the header after prepare0 has been made, hence
 179# this hack.
 180prepare: vdso_prepare
 181vdso_prepare: prepare0
 182        $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso include/generated/vdso-offsets.h
 183        $(if $(CONFIG_COMPAT_VDSO),$(Q)$(MAKE) \
 184                $(build)=arch/arm64/kernel/vdso32  \
 185                include/generated/vdso32-offsets.h)
 186endif
 187
 188define archhelp
 189  echo  '* Image.gz      - Compressed kernel image (arch/$(ARCH)/boot/Image.gz)'
 190  echo  '  Image         - Uncompressed kernel image (arch/$(ARCH)/boot/Image)'
 191  echo  '  install       - Install uncompressed kernel'
 192  echo  '  zinstall      - Install compressed kernel'
 193  echo  '                  Install using (your) ~/bin/installkernel or'
 194  echo  '                  (distribution) /sbin/installkernel or'
 195  echo  '                  install to $$(INSTALL_PATH) and run lilo'
 196endef
 197