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
  13 LDFLAGS_vmlinux :=--no-undefined -X -z norelro
  14
  15 ifeq ($(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.
  19 LDFLAGS_vmlinux         += -shared -Bsymbolic -z notext \
  20                         $(call ld-option, --no-apply-dynamic-relocs)
  21 endif
  22
  23 ifeq ($(CONFIG_ARM64_ERRATUM_843419),y)
  24   ifeq ($(call ld-option, --fix-cortex-a53-843419),)
  25 $(warning ld does not support --fix-cortex-a53-843419; kernel may be susceptible to erratum)
  26   else
  27 LDFLAGS_vmlinux += --fix-cortex-a53-843419
  28   endif
  29 endif
  30
  31 ifeq ($(CONFIG_ARM64_USE_LSE_ATOMICS), y)
  32   ifneq ($(CONFIG_ARM64_LSE_ATOMICS), y)
  33 $(warning LSE atomics not supported by binutils)
  34   endif
  35 endif
  36
  37 cc_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 "$$TMP" -,,-DCONFIG_CC_HAS_K_CONSTRAINT=1)
  42
  43 ifeq ($(CONFIG_BROKEN_GAS_INST),y)
  44 $(warning Detected assembler with broken .inst; disassembly will be unreliable)
  45 endif
  46
  47 KBUILD_CFLAGS   += -mgeneral-regs-only  \
  48                    $(compat_vdso) $(cc_has_k_constraint)
  49 KBUILD_CFLAGS   += $(call cc-disable-warning, psabi)
  50 KBUILD_AFLAGS   += $(compat_vdso)
  51
  52 KBUILD_CFLAGS   += $(call cc-option,-mabi=lp64)
  53 KBUILD_AFLAGS   += $(call cc-option,-mabi=lp64)
  54
  55 # Avoid generating .eh_frame* sections.
  56 KBUILD_CFLAGS   += -fno-asynchronous-unwind-tables -fno-unwind-tables
  57 KBUILD_AFLAGS   += -fno-asynchronous-unwind-tables -fno-unwind-tables
  58
  59 ifeq ($(CONFIG_STACKPROTECTOR_PER_TASK),y)
  60 prepare: stack_protector_prepare
  61 stack_protector_prepare: prepare0
  62         $(eval KBUILD_CFLAGS += -mstack-protector-guard=sysreg            \
  63                                 -mstack-protector-guard-reg=sp_el0        \
  64                                 -mstack-protector-guard-offset=$(shell    \
  65                         awk '{if ($$2 == "TSK_STACK_CANARY") print $$3;}' \
  66                                         include/generated/asm-offsets.h))
  67 endif
  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.
  71 branch-prot-flags-y += $(call cc-option,-mbranch-protection=none)
  72
  73 ifeq ($(CONFIG_ARM64_PTR_AUTH),y)
  74 branch-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.
  78 ifeq ($(CONFIG_ARM64_BTI_KERNEL),y)
  79 branch-prot-flags-$(CONFIG_CC_HAS_BRANCH_PROT_PAC_RET_BTI) := -mbranch-protection=pac-ret+leaf+bti
  80 else
  81 branch-prot-flags-$(CONFIG_CC_HAS_BRANCH_PROT_PAC_RET) := -mbranch-protection=pac-ret+leaf
  82 endif
  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.
  87 ifeq ($(CONFIG_AS_HAS_PAC), y)
  88 asm-arch := armv8.3-a
  89 endif
  90 endif
  91
  92 KBUILD_CFLAGS += $(branch-prot-flags-y)
  93
  94 ifeq ($(CONFIG_AS_HAS_ARMV8_4), y)
  95 # make sure to pass the newest target architecture to -march.
  96 asm-arch := armv8.4-a
  97 endif
  98
  99 ifeq ($(CONFIG_AS_HAS_ARMV8_5), y)
 100 # make sure to pass the newest target architecture to -march.
 101 asm-arch := armv8.5-a
 102 endif
 103
 104 ifdef asm-arch
 105 KBUILD_CFLAGS   += -Wa,-march=$(asm-arch) \
 106                    -DARM64_ASM_ARCH='"$(asm-arch)"'
 107 endif
 108
 109 ifeq ($(CONFIG_SHADOW_CALL_STACK), y)
 110 KBUILD_CFLAGS   += -ffixed-x18
 111 endif
 112
 113 ifeq ($(CONFIG_CPU_BIG_ENDIAN), y)
 114 KBUILD_CPPFLAGS += -mbig-endian
 115 CHECKFLAGS      += -D__AARCH64EB__
 116 # Prefer the baremetal ELF build target, but not all toolchains include
 117 # it so fall back to the standard linux version if needed.
 118 KBUILD_LDFLAGS  += -EB $(call ld-option, -maarch64elfb, -maarch64linuxb)
 119 UTS_MACHINE     := aarch64_be
 120 else
 121 KBUILD_CPPFLAGS += -mlittle-endian
 122 CHECKFLAGS      += -D__AARCH64EL__
 123 # Same as above, prefer ELF but fall back to linux target if needed.
 124 KBUILD_LDFLAGS  += -EL $(call ld-option, -maarch64elf, -maarch64linux)
 125 UTS_MACHINE     := aarch64
 126 endif
 127
 128 CHECKFLAGS      += -D__aarch64__
 129
 130 ifeq ($(CONFIG_DYNAMIC_FTRACE_WITH_REGS),y)
 131   KBUILD_CPPFLAGS += -DCC_USING_PATCHABLE_FUNCTION_ENTRY
 132   CC_FLAGS_FTRACE := -fpatchable-function-entry=2
 133 endif
 134
 135 # Default value
 136 head-y          := arch/arm64/kernel/head.o
 137
 138 ifeq ($(CONFIG_KASAN_SW_TAGS), y)
 139 KASAN_SHADOW_SCALE_SHIFT := 4
 140 else ifeq ($(CONFIG_KASAN_GENERIC), y)
 141 KASAN_SHADOW_SCALE_SHIFT := 3
 142 endif
 143
 144 KBUILD_CFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT)
 145 KBUILD_CPPFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT)
 146 KBUILD_AFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT)
 147
 148 core-y          += arch/arm64/
 149 libs-y          := arch/arm64/lib/ $(libs-y)
 150 libs-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a
 151
 152 # Default target when executing plain make
 153 boot            := arch/arm64/boot
 154 KBUILD_IMAGE    := $(boot)/Image.gz
 155
 156 all:    Image.gz
 157
 158
 159 Image: vmlinux
 160         $(Q)$(MAKE) $(build)=$(boot) $(boot)/$@
 161
 162 Image.%: Image
 163         $(Q)$(MAKE) $(build)=$(boot) $(boot)/$@
 164
 165 zinstall install:
 166         $(Q)$(MAKE) $(build)=$(boot) $@
 167
 168 PHONY += vdso_install
 169 vdso_install:
 170         $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso $@
 171         $(if $(CONFIG_COMPAT_VDSO), \
 172                 $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso32 $@)
 173
 174 # We use MRPROPER_FILES and CLEAN_FILES now
 175 archclean:
 176         $(Q)$(MAKE) $(clean)=$(boot)
 177
 178 ifeq ($(KBUILD_EXTMOD),)
 179 # We need to generate vdso-offsets.h before compiling certain files in kernel/.
 180 # In order to do that, we should use the archprepare target, but we can't since
 181 # asm-offsets.h is included in some files used to generate vdso-offsets.h, and
 182 # asm-offsets.h is built in prepare0, for which archprepare is a dependency.
 183 # Therefore we need to generate the header after prepare0 has been made, hence
 184 # this hack.
 185 prepare: vdso_prepare
 186 vdso_prepare: prepare0
 187         $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso include/generated/vdso-offsets.h
 188         $(if $(CONFIG_COMPAT_VDSO),$(Q)$(MAKE) \
 189                 $(build)=arch/arm64/kernel/vdso32  \
 190                 include/generated/vdso32-offsets.h)
 191 endif
 192
 193 define archhelp
 194   echo  '* Image.gz      - Compressed kernel image (arch/$(ARCH)/boot/Image.gz)'
 195   echo  '  Image         - Uncompressed kernel image (arch/$(ARCH)/boot/Image)'
 196   echo  '  install       - Install uncompressed kernel'
 197   echo  '  zinstall      - Install compressed kernel'
 198   echo  '                  Install using (your) ~/bin/installkernel or'
 199   echo  '                  (distribution) /sbin/installkernel or'
 200   echo  '                  install to $$(INSTALL_PATH) and run lilo'
 201 endef