xref: /openbmc/linux/arch/arm64/kvm/hyp/nvhe/Makefile (revision c2a5a45c)
1# SPDX-License-Identifier: GPL-2.0
2#
3# Makefile for Kernel-based Virtual Machine module, HYP/nVHE part
4#
5
6asflags-y := -D__KVM_NVHE_HYPERVISOR__ -D__DISABLE_EXPORTS
7ccflags-y := -D__KVM_NVHE_HYPERVISOR__ -D__DISABLE_EXPORTS
8
9hostprogs := gen-hyprel
10HOST_EXTRACFLAGS += -I$(objtree)/include
11
12obj-y := timer-sr.o sysreg-sr.o debug-sr.o switch.o tlb.o hyp-init.o host.o \
13	 hyp-main.o hyp-smp.o psci-relay.o
14obj-y += ../vgic-v3-sr.o ../aarch32.o ../vgic-v2-cpuif-proxy.o ../entry.o \
15	 ../fpsimd.o ../hyp-entry.o ../exception.o
16
17##
18## Build rules for compiling nVHE hyp code
19## Output of this folder is `kvm_nvhe.o`, a partially linked object
20## file containing all nVHE hyp code and data.
21##
22
23hyp-obj := $(patsubst %.o,%.nvhe.o,$(obj-y))
24obj-y := kvm_nvhe.o
25extra-y := $(hyp-obj) kvm_nvhe.tmp.o kvm_nvhe.rel.o hyp.lds hyp-reloc.S hyp-reloc.o
26
27# 1) Compile all source files to `.nvhe.o` object files. The file extension
28#    avoids file name clashes for files shared with VHE.
29$(obj)/%.nvhe.o: $(src)/%.c FORCE
30	$(call if_changed_rule,cc_o_c)
31$(obj)/%.nvhe.o: $(src)/%.S FORCE
32	$(call if_changed_rule,as_o_S)
33
34# 2) Compile linker script.
35$(obj)/hyp.lds: $(src)/hyp.lds.S FORCE
36	$(call if_changed_dep,cpp_lds_S)
37
38# 3) Partially link all '.nvhe.o' files and apply the linker script.
39#    Prefixes names of ELF sections with '.hyp', eg. '.hyp.text'.
40#    Note: The following rule assumes that the 'ld' rule puts LDFLAGS before
41#          the list of dependencies to form '-T $(obj)/hyp.lds'. This is to
42#          keep the dependency on the target while avoiding an error from
43#          GNU ld if the linker script is passed to it twice.
44LDFLAGS_kvm_nvhe.tmp.o := -r -T
45$(obj)/kvm_nvhe.tmp.o: $(obj)/hyp.lds $(addprefix $(obj)/,$(hyp-obj)) FORCE
46	$(call if_changed,ld)
47
48# 4) Generate list of hyp code/data positions that need to be relocated at
49#    runtime. Because the hypervisor is part of the kernel binary, relocations
50#    produce a kernel VA. We enumerate relocations targeting hyp at build time
51#    and convert the kernel VAs at those positions to hyp VAs.
52$(obj)/hyp-reloc.S: $(obj)/kvm_nvhe.tmp.o $(obj)/gen-hyprel
53	$(call if_changed,hyprel)
54
55# 5) Compile hyp-reloc.S and link it into the existing partially linked object.
56#    The object file now contains a section with pointers to hyp positions that
57#    will contain kernel VAs at runtime. These pointers have relocations on them
58#    so that they get updated as the hyp object is linked into `vmlinux`.
59LDFLAGS_kvm_nvhe.rel.o := -r
60$(obj)/kvm_nvhe.rel.o: $(obj)/kvm_nvhe.tmp.o $(obj)/hyp-reloc.o FORCE
61	$(call if_changed,ld)
62
63# 6) Produce the final 'kvm_nvhe.o', ready to be linked into 'vmlinux'.
64#    Prefixes names of ELF symbols with '__kvm_nvhe_'.
65$(obj)/kvm_nvhe.o: $(obj)/kvm_nvhe.rel.o FORCE
66	$(call if_changed,hypcopy)
67
68# The HYPREL command calls `gen-hyprel` to generate an assembly file with
69# a list of relocations targeting hyp code/data.
70quiet_cmd_hyprel = HYPREL  $@
71      cmd_hyprel = $(obj)/gen-hyprel $< > $@
72
73# The HYPCOPY command uses `objcopy` to prefix all ELF symbol names
74# to avoid clashes with VHE code/data.
75quiet_cmd_hypcopy = HYPCOPY $@
76      cmd_hypcopy = $(OBJCOPY) --prefix-symbols=__kvm_nvhe_ $< $@
77
78# Remove ftrace and Shadow Call Stack CFLAGS.
79# This is equivalent to the 'notrace' and '__noscs' annotations.
80KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_FTRACE) $(CC_FLAGS_SCS), $(KBUILD_CFLAGS))
81
82# KVM nVHE code is run at a different exception code with a different map, so
83# compiler instrumentation that inserts callbacks or checks into the code may
84# cause crashes. Just disable it.
85GCOV_PROFILE	:= n
86KASAN_SANITIZE	:= n
87UBSAN_SANITIZE	:= n
88KCOV_INSTRUMENT	:= n
89
90# Skip objtool checking for this directory because nVHE code is compiled with
91# non-standard build rules.
92OBJECT_FILES_NON_STANDARD := y
93