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 $(warning ld does not support --fix-cortex-a53-843419; kernel may be susceptible to erratum)
  28   else
  29 LDFLAGS_vmlinux += --fix-cortex-a53-843419
  30   endif
  31 endif
  32
  33 ifeq ($(CONFIG_ARM64_USE_LSE_ATOMICS), y)
  34   ifneq ($(CONFIG_ARM64_LSE_ATOMICS), y)
  35 $(warning LSE atomics not supported by binutils)
  36   endif
  37 endif
  38
  39 cc_has_k_constraint := $(call try-run,echo                              \
  40         'int main(void) {                                               \
  41                 asm volatile("and w0, w0, %w0" :: "K" (4294967295));    \
  42                 return 0;                                               \
  43         }' | $(CC) -S -x c -o "$$TMP" -,,-DCONFIG_CC_HAS_K_CONSTRAINT=1)
  44
  45 ifeq ($(CONFIG_BROKEN_GAS_INST),y)
  46 $(warning Detected assembler with broken .inst; disassembly will be unreliable)
  47 endif
  48
  49 KBUILD_CFLAGS   += -mgeneral-regs-only  \
  50                    $(compat_vdso) $(cc_has_k_constraint)
  51 KBUILD_CFLAGS   += -fno-asynchronous-unwind-tables
  52 KBUILD_CFLAGS   += $(call cc-disable-warning, psabi)
  53 KBUILD_AFLAGS   += $(compat_vdso)
  54
  55 KBUILD_CFLAGS   += $(call cc-option,-mabi=lp64)
  56 KBUILD_AFLAGS   += $(call cc-option,-mabi=lp64)
  57
  58 ifeq ($(CONFIG_STACKPROTECTOR_PER_TASK),y)
  59 prepare: stack_protector_prepare
  60 stack_protector_prepare: prepare0
  61         $(eval KBUILD_CFLAGS += -mstack-protector-guard=sysreg            \
  62                                 -mstack-protector-guard-reg=sp_el0        \
  63                                 -mstack-protector-guard-offset=$(shell    \
  64                         awk '{if ($$2 == "TSK_STACK_CANARY") print $$3;}' \
  65                                         include/generated/asm-offsets.h))
  66 endif
  67
  68 # Ensure that if the compiler supports branch protection we default it
  69 # off, this will be overridden if we are using branch protection.
  70 branch-prot-flags-y += $(call cc-option,-mbranch-protection=none)
  71
  72 ifeq ($(CONFIG_ARM64_PTR_AUTH),y)
  73 branch-prot-flags-$(CONFIG_CC_HAS_SIGN_RETURN_ADDRESS) := -msign-return-address=all
  74 branch-prot-flags-$(CONFIG_CC_HAS_BRANCH_PROT_PAC_RET) := -mbranch-protection=pac-ret+leaf
  75 # -march=armv8.3-a enables the non-nops instructions for PAC, to avoid the
  76 # compiler to generate them and consequently to break the single image contract
  77 # we pass it only to the assembler. This option is utilized only in case of non
  78 # integrated assemblers.
  79 branch-prot-flags-$(CONFIG_AS_HAS_PAC) += -Wa,-march=armv8.3-a
  80 endif
  81
  82 KBUILD_CFLAGS += $(branch-prot-flags-y)
  83
  84 ifeq ($(CONFIG_CPU_BIG_ENDIAN), y)
  85 KBUILD_CPPFLAGS += -mbig-endian
  86 CHECKFLAGS      += -D__AARCH64EB__
  87 AS              += -EB
  88 # Prefer the baremetal ELF build target, but not all toolchains include
  89 # it so fall back to the standard linux version if needed.
  90 KBUILD_LDFLAGS  += -EB $(call ld-option, -maarch64elfb, -maarch64linuxb)
  91 UTS_MACHINE     := aarch64_be
  92 else
  93 KBUILD_CPPFLAGS += -mlittle-endian
  94 CHECKFLAGS      += -D__AARCH64EL__
  95 AS              += -EL
  96 # Same as above, prefer ELF but fall back to linux target if needed.
  97 KBUILD_LDFLAGS  += -EL $(call ld-option, -maarch64elf, -maarch64linux)
  98 UTS_MACHINE     := aarch64
  99 endif
 100
 101 CHECKFLAGS      += -D__aarch64__
 102
 103 ifeq ($(CONFIG_ARM64_MODULE_PLTS),y)
 104 KBUILD_LDS_MODULE       += $(srctree)/arch/arm64/kernel/module.lds
 105 endif
 106
 107 ifeq ($(CONFIG_DYNAMIC_FTRACE_WITH_REGS),y)
 108   KBUILD_CPPFLAGS += -DCC_USING_PATCHABLE_FUNCTION_ENTRY
 109   CC_FLAGS_FTRACE := -fpatchable-function-entry=2
 110 endif
 111
 112 # Default value
 113 head-y          := arch/arm64/kernel/head.o
 114
 115 # The byte offset of the kernel image in RAM from the start of RAM.
 116 ifeq ($(CONFIG_ARM64_RANDOMIZE_TEXT_OFFSET), y)
 117 TEXT_OFFSET := $(shell awk "BEGIN {srand(); printf \"0x%06x\n\", \
 118                  int(2 * 1024 * 1024 / (2 ^ $(CONFIG_ARM64_PAGE_SHIFT)) * \
 119                  rand()) * (2 ^ $(CONFIG_ARM64_PAGE_SHIFT))}")
 120 else
 121 TEXT_OFFSET := 0x00080000
 122 endif
 123
 124 ifeq ($(CONFIG_KASAN_SW_TAGS), y)
 125 KASAN_SHADOW_SCALE_SHIFT := 4
 126 else
 127 KASAN_SHADOW_SCALE_SHIFT := 3
 128 endif
 129
 130 KBUILD_CFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT)
 131 KBUILD_CPPFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT)
 132 KBUILD_AFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT)
 133
 134 export  TEXT_OFFSET GZFLAGS
 135
 136 core-y          += arch/arm64/
 137 libs-y          := arch/arm64/lib/ $(libs-y)
 138 core-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a
 139
 140 # Default target when executing plain make
 141 boot            := arch/arm64/boot
 142 KBUILD_IMAGE    := $(boot)/Image.gz
 143
 144 all:    Image.gz
 145
 146
 147 Image: vmlinux
 148         $(Q)$(MAKE) $(build)=$(boot) $(boot)/$@
 149
 150 Image.%: Image
 151         $(Q)$(MAKE) $(build)=$(boot) $(boot)/$@
 152
 153 zinstall install:
 154         $(Q)$(MAKE) $(build)=$(boot) $@
 155
 156 PHONY += vdso_install
 157 vdso_install:
 158         $(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso $@
 159
 160 # We use MRPROPER_FILES and CLEAN_FILES now
 161 archclean:
 162         $(Q)$(MAKE) $(clean)=$(boot)
 163
 164 ifeq ($(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.
 171 prepare: vdso_prepare
 172 vdso_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)
 177 endif
 178
 179 define 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'
 187 endef