xref: /openbmc/linux/arch/arm64/Makefile (revision adb57164)
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
14CPPFLAGS_vmlinux.lds = -DTEXT_OFFSET=$(TEXT_OFFSET)
15GZFLAGS		:=-9
16
17ifeq ($(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.
21LDFLAGS_vmlinux		+= -shared -Bsymbolic -z notext -z norelro \
22			$(call ld-option, --no-apply-dynamic-relocs)
23endif
24
25ifeq ($(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
29LDFLAGS_vmlinux	+= --fix-cortex-a53-843419
30  endif
31endif
32
33ifeq ($(CONFIG_ARM64_USE_LSE_ATOMICS), y)
34  ifneq ($(CONFIG_ARM64_LSE_ATOMICS), y)
35$(warning LSE atomics not supported by binutils)
36  endif
37endif
38
39cc_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 "$$TMP" -,,-DCONFIG_CC_HAS_K_CONSTRAINT=1)
44
45ifeq ($(CONFIG_BROKEN_GAS_INST),y)
46$(warning Detected assembler with broken .inst; disassembly will be unreliable)
47endif
48
49KBUILD_CFLAGS	+= -mgeneral-regs-only	\
50		   $(compat_vdso) $(cc_has_k_constraint)
51KBUILD_CFLAGS	+= -fno-asynchronous-unwind-tables
52KBUILD_CFLAGS	+= $(call cc-disable-warning, psabi)
53KBUILD_AFLAGS	+= $(compat_vdso)
54
55KBUILD_CFLAGS	+= $(call cc-option,-mabi=lp64)
56KBUILD_AFLAGS	+= $(call cc-option,-mabi=lp64)
57
58ifeq ($(CONFIG_STACKPROTECTOR_PER_TASK),y)
59prepare: stack_protector_prepare
60stack_protector_prepare: prepare0
61	$(eval KBUILD_CFLAGS += -mstack-protector-guard=sysreg		  \
62				-mstack-protector-guard-reg=sp_el0	  \
63				-mstack-protector-guard-offset=$(shell	  \
64			awk '{if ($$2 == "TSK_STACK_CANARY") print $$3;}' \
65					include/generated/asm-offsets.h))
66endif
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.
70branch-prot-flags-y += $(call cc-option,-mbranch-protection=none)
71
72ifeq ($(CONFIG_ARM64_PTR_AUTH),y)
73branch-prot-flags-$(CONFIG_CC_HAS_SIGN_RETURN_ADDRESS) := -msign-return-address=all
74branch-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.
79branch-prot-flags-$(CONFIG_AS_HAS_PAC) += -Wa,-march=armv8.3-a
80endif
81
82KBUILD_CFLAGS += $(branch-prot-flags-y)
83
84ifeq ($(CONFIG_CPU_BIG_ENDIAN), y)
85KBUILD_CPPFLAGS	+= -mbig-endian
86CHECKFLAGS	+= -D__AARCH64EB__
87AS		+= -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.
90KBUILD_LDFLAGS	+= -EB $(call ld-option, -maarch64elfb, -maarch64linuxb)
91UTS_MACHINE	:= aarch64_be
92else
93KBUILD_CPPFLAGS	+= -mlittle-endian
94CHECKFLAGS	+= -D__AARCH64EL__
95AS		+= -EL
96# Same as above, prefer ELF but fall back to linux target if needed.
97KBUILD_LDFLAGS	+= -EL $(call ld-option, -maarch64elf, -maarch64linux)
98UTS_MACHINE	:= aarch64
99endif
100
101CHECKFLAGS	+= -D__aarch64__
102
103ifeq ($(CONFIG_ARM64_MODULE_PLTS),y)
104KBUILD_LDS_MODULE	+= $(srctree)/arch/arm64/kernel/module.lds
105endif
106
107ifeq ($(CONFIG_DYNAMIC_FTRACE_WITH_REGS),y)
108  KBUILD_CPPFLAGS += -DCC_USING_PATCHABLE_FUNCTION_ENTRY
109  CC_FLAGS_FTRACE := -fpatchable-function-entry=2
110endif
111
112# Default value
113head-y		:= arch/arm64/kernel/head.o
114
115# The byte offset of the kernel image in RAM from the start of RAM.
116ifeq ($(CONFIG_ARM64_RANDOMIZE_TEXT_OFFSET), y)
117TEXT_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))}")
120else
121TEXT_OFFSET := 0x00080000
122endif
123
124ifeq ($(CONFIG_KASAN_SW_TAGS), y)
125KASAN_SHADOW_SCALE_SHIFT := 4
126else
127KASAN_SHADOW_SCALE_SHIFT := 3
128endif
129
130KBUILD_CFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT)
131KBUILD_CPPFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT)
132KBUILD_AFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT)
133
134export	TEXT_OFFSET GZFLAGS
135
136core-y		+= arch/arm64/
137libs-y		:= arch/arm64/lib/ $(libs-y)
138core-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a
139
140# Default target when executing plain make
141boot		:= arch/arm64/boot
142KBUILD_IMAGE	:= $(boot)/Image.gz
143
144all:	Image.gz
145
146
147Image: vmlinux
148	$(Q)$(MAKE) $(build)=$(boot) $(boot)/$@
149
150Image.%: Image
151	$(Q)$(MAKE) $(build)=$(boot) $(boot)/$@
152
153zinstall install:
154	$(Q)$(MAKE) $(build)=$(boot) $@
155
156PHONY += vdso_install
157vdso_install:
158	$(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso $@
159
160# We use MRPROPER_FILES and CLEAN_FILES now
161archclean:
162	$(Q)$(MAKE) $(clean)=$(boot)
163
164ifeq ($(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.
171prepare: vdso_prepare
172vdso_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)
177endif
178
179define 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'
187endef
188