xref: /openbmc/linux/arch/arm64/Makefile (revision 28949b84b2cb2473507ec2fed06728f995dd7942)
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__
87# Prefer the baremetal ELF build target, but not all toolchains include
88# it so fall back to the standard linux version if needed.
89KBUILD_LDFLAGS	+= -EB $(call ld-option, -maarch64elfb, -maarch64linuxb)
90UTS_MACHINE	:= aarch64_be
91else
92KBUILD_CPPFLAGS	+= -mlittle-endian
93CHECKFLAGS	+= -D__AARCH64EL__
94# Same as above, prefer ELF but fall back to linux target if needed.
95KBUILD_LDFLAGS	+= -EL $(call ld-option, -maarch64elf, -maarch64linux)
96UTS_MACHINE	:= aarch64
97endif
98
99CHECKFLAGS	+= -D__aarch64__
100
101ifeq ($(CONFIG_ARM64_MODULE_PLTS),y)
102KBUILD_LDS_MODULE	+= $(srctree)/arch/arm64/kernel/module.lds
103endif
104
105ifeq ($(CONFIG_DYNAMIC_FTRACE_WITH_REGS),y)
106  KBUILD_CPPFLAGS += -DCC_USING_PATCHABLE_FUNCTION_ENTRY
107  CC_FLAGS_FTRACE := -fpatchable-function-entry=2
108endif
109
110# Default value
111head-y		:= arch/arm64/kernel/head.o
112
113# The byte offset of the kernel image in RAM from the start of RAM.
114ifeq ($(CONFIG_ARM64_RANDOMIZE_TEXT_OFFSET), y)
115TEXT_OFFSET := $(shell awk "BEGIN {srand(); printf \"0x%06x\n\", \
116		 int(2 * 1024 * 1024 / (2 ^ $(CONFIG_ARM64_PAGE_SHIFT)) * \
117		 rand()) * (2 ^ $(CONFIG_ARM64_PAGE_SHIFT))}")
118else
119TEXT_OFFSET := 0x00080000
120endif
121
122ifeq ($(CONFIG_KASAN_SW_TAGS), y)
123KASAN_SHADOW_SCALE_SHIFT := 4
124else
125KASAN_SHADOW_SCALE_SHIFT := 3
126endif
127
128KBUILD_CFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT)
129KBUILD_CPPFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT)
130KBUILD_AFLAGS += -DKASAN_SHADOW_SCALE_SHIFT=$(KASAN_SHADOW_SCALE_SHIFT)
131
132export	TEXT_OFFSET GZFLAGS
133
134core-y		+= arch/arm64/
135libs-y		:= arch/arm64/lib/ $(libs-y)
136core-$(CONFIG_EFI_STUB) += $(objtree)/drivers/firmware/efi/libstub/lib.a
137
138# Default target when executing plain make
139boot		:= arch/arm64/boot
140KBUILD_IMAGE	:= $(boot)/Image.gz
141
142all:	Image.gz
143
144
145Image: vmlinux
146	$(Q)$(MAKE) $(build)=$(boot) $(boot)/$@
147
148Image.%: Image
149	$(Q)$(MAKE) $(build)=$(boot) $(boot)/$@
150
151zinstall install:
152	$(Q)$(MAKE) $(build)=$(boot) $@
153
154PHONY += vdso_install
155vdso_install:
156	$(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso $@
157
158# We use MRPROPER_FILES and CLEAN_FILES now
159archclean:
160	$(Q)$(MAKE) $(clean)=$(boot)
161
162ifeq ($(KBUILD_EXTMOD),)
163# We need to generate vdso-offsets.h before compiling certain files in kernel/.
164# In order to do that, we should use the archprepare target, but we can't since
165# asm-offsets.h is included in some files used to generate vdso-offsets.h, and
166# asm-offsets.h is built in prepare0, for which archprepare is a dependency.
167# Therefore we need to generate the header after prepare0 has been made, hence
168# this hack.
169prepare: vdso_prepare
170vdso_prepare: prepare0
171	$(Q)$(MAKE) $(build)=arch/arm64/kernel/vdso include/generated/vdso-offsets.h
172	$(if $(CONFIG_COMPAT_VDSO),$(Q)$(MAKE) \
173		$(build)=arch/arm64/kernel/vdso32  \
174		include/generated/vdso32-offsets.h)
175endif
176
177define archhelp
178  echo  '* Image.gz      - Compressed kernel image (arch/$(ARCH)/boot/Image.gz)'
179  echo  '  Image         - Uncompressed kernel image (arch/$(ARCH)/boot/Image)'
180  echo  '  install       - Install uncompressed kernel'
181  echo  '  zinstall      - Install compressed kernel'
182  echo  '                  Install using (your) ~/bin/installkernel or'
183  echo  '                  (distribution) /sbin/installkernel or'
184  echo  '                  install to $$(INSTALL_PATH) and run lilo'
185endef
186