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