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
  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 -z norelro \
  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 "$$TMP" -,,-DCONFIG_CC_HAS_K_CONSTRAINT=1)
  47
  48 ifeq ($(CONFIG_ARM64), y)
  49 brokengasinst := $(call as-instr,1:\n.inst 0\n.rept . - 1b\n\nnop\n.endr\n,,-DCONFIG_BROKEN_GAS_INST=1)
  50
  51   ifneq ($(brokengasinst),)
  52 $(warning Detected assembler with broken .inst; disassembly will be unreliable)
  53   endif
  54 endif
  55
  56 ifeq ($(CONFIG_GENERIC_COMPAT_VDSO), y)
  57   CROSS_COMPILE_COMPAT ?= $(CONFIG_CROSS_COMPILE_COMPAT_VDSO:"%"=%)
  58
  59   ifeq ($(CONFIG_CC_IS_CLANG), y)
  60     $(warning CROSS_COMPILE_COMPAT is clang, the compat vDSO will not be built)
  61   else ifeq ($(strip $(CROSS_COMPILE_COMPAT)),)
  62     $(warning CROSS_COMPILE_COMPAT not defined or empty, the compat vDSO will not be built)
  63   else ifeq ($(shell which $(CROSS_COMPILE_COMPAT)gcc 2> /dev/null),)
  64     $(error $(CROSS_COMPILE_COMPAT)gcc not found, check CROSS_COMPILE_COMPAT)
  65   else
  66     export CROSS_COMPILE_COMPAT
  67     export CONFIG_COMPAT_VDSO := y
  68     compat_vdso := -DCONFIG_COMPAT_VDSO=1
  69   endif
  70 endif
  71
  72 KBUILD_CFLAGS   += -mgeneral-regs-only $(lseinstr) $(brokengasinst)     \
  73                    $(compat_vdso) $(cc_has_k_constraint)
  74 KBUILD_CFLAGS   += -fno-asynchronous-unwind-tables
  75 KBUILD_CFLAGS   += $(call cc-disable-warning, psabi)
  76 KBUILD_AFLAGS   += $(lseinstr) $(brokengasinst) $(compat_vdso)
  77
  78 KBUILD_CFLAGS   += $(call cc-option,-mabi=lp64)
  79 KBUILD_AFLAGS   += $(call cc-option,-mabi=lp64)
  80
  81 ifeq ($(CONFIG_STACKPROTECTOR_PER_TASK),y)
  82 prepare: stack_protector_prepare
  83 stack_protector_prepare: prepare0
  84         $(eval KBUILD_CFLAGS += -mstack-protector-guard=sysreg            \
  85                                 -mstack-protector-guard-reg=sp_el0        \
  86                                 -mstack-protector-guard-offset=$(shell    \
  87                         awk '{if ($$2 == "TSK_STACK_CANARY") print $$3;}' \
  88                                         include/generated/asm-offsets.h))
  89 endif
  90
  91 ifeq ($(CONFIG_CPU_BIG_ENDIAN), y)
  92 KBUILD_CPPFLAGS += -mbig-endian
  93 CHECKFLAGS      += -D__AARCH64EB__
  94 AS              += -EB
  95 # Prefer the baremetal ELF build target, but not all toolchains include
  96 # it so fall back to the standard linux version if needed.
  97 KBUILD_LDFLAGS  += -EB $(call ld-option, -maarch64elfb, -maarch64linuxb)
  98 UTS_MACHINE     := aarch64_be
  99 else
 100 KBUILD_CPPFLAGS += -mlittle-endian
 101 CHECKFLAGS      += -D__AARCH64EL__
 102 AS              += -EL
 103 # Same as above, prefer ELF but fall back to linux target if needed.
 104 KBUILD_LDFLAGS  += -EL $(call ld-option, -maarch64elf, -maarch64linux)
 105 UTS_MACHINE     := aarch64
 106 endif
 107
 108 CHECKFLAGS      += -D__aarch64__
 109
 110 ifeq ($(CONFIG_ARM64_MODULE_PLTS),y)
 111 KBUILD_LDS_MODULE       += $(srctree)/arch/arm64/kernel/module.lds
 112 endif
 113
 114 # Default value
 115 head-y          := arch/arm64/kernel/head.o
 116
 117 # The byte offset of the kernel image in RAM from the start of RAM.
 118 ifeq ($(CONFIG_ARM64_RANDOMIZE_TEXT_OFFSET), y)
 119 TEXT_OFFSET := $(shell awk "BEGIN {srand(); printf \"0x%06x\n\", \
 120                  int(2 * 1024 * 1024 / (2 ^ $(CONFIG_ARM64_PAGE_SHIFT)) * \
 121                  rand()) * (2 ^ $(CONFIG_ARM64_PAGE_SHIFT))}")
 122 else
 123 TEXT_OFFSET := 0x00080000
 124 endif
 125
 126 ifeq ($(CONFIG_KASAN_SW_TAGS), y)
 127 KASAN_SHADOW_SCALE_SHIFT := 4
 128 else
 129 KASAN_SHADOW_SCALE_SHIFT := 3
 130 endif
 131
 132 KBUILD_CFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT)
 133 KBUILD_CPPFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT)
 134 KBUILD_AFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT)
 135
 136 export  TEXT_OFFSET GZFLAGS
 137
 138 core-y          += arch/arm64/
 139 libs-y          := arch/arm64/lib/ $(libs-y)
 140 core-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a
 141
 142 # Default target when executing plain make
 143 boot            := arch/arm64/boot
 144 KBUILD_IMAGE    := $(boot)/Image.gz
 145
 146 all:    Image.gz
 147
 148
 149 Image: vmlinux
 150         $(Q)$(MAKE) $(build)=$(boot) $(boot)/$@
 151
 152 Image.%: Image
 153         $(Q)$(MAKE) $(build)=$(boot) $(boot)/$@
 154
 155 zinstall install:
 156         $(Q)$(MAKE) $(build)=$(boot) $@
 157
 158 PHONY += vdso_install
 159 vdso_install:
 160         $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso $@
 161
 162 # We use MRPROPER_FILES and CLEAN_FILES now
 163 archclean:
 164         $(Q)$(MAKE) $(clean)=$(boot)
 165
 166 ifeq ($(KBUILD_EXTMOD),)
 167 # We need to generate vdso-offsets.h before compiling certain files in kernel/.
 168 # In order to do that, we should use the archprepare target, but we can't since
 169 # asm-offsets.h is included in some files used to generate vdso-offsets.h, and
 170 # asm-offsets.h is built in prepare0, for which archprepare is a dependency.
 171 # Therefore we need to generate the header after prepare0 has been made, hence
 172 # this hack.
 173 prepare: vdso_prepare
 174 vdso_prepare: prepare0
 175         $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso include/generated/vdso-offsets.h
 176         $(if $(CONFIG_COMPAT_VDSO),$(Q)$(MAKE) \
 177                 $(build)=arch/arm64/kernel/vdso32  \
 178                 include/generated/vdso32-offsets.h)
 179 endif
 180
 181 define archhelp
 182   echo  '* Image.gz      - Compressed kernel image (arch/$(ARCH)/boot/Image.gz)'
 183   echo  '  Image         - Uncompressed kernel image (arch/$(ARCH)/boot/Image)'
 184   echo  '  install       - Install uncompressed kernel'
 185   echo  '  zinstall      - Install compressed kernel'
 186   echo  '                  Install using (your) ~/bin/installkernel or'
 187   echo  '                  (distribution) /sbin/installkernel or'
 188   echo  '                  install to $$(INSTALL_PATH) and run lilo'
 189 endef