1#
2# Building a vDSO image for AArch64.
3#
4# Author: Will Deacon <will.deacon@arm.com>
5# Heavily based on the vDSO Makefiles for other archs.
6#
7
8obj-vdso := note.o datapage.o sigreturn.o gettimeofday.o
9
10# Build rules
11targets := $(obj-vdso) vdso.so vdso.so.dbg
12obj-vdso := $(addprefix $(obj)/, $(obj-vdso))
13
14ccflags-y := -shared -fno-common -fno-builtin
15ccflags-y += -nostdlib -Wl,-soname=linux-vdso.so.1 \
16		$(call cc-ldoption, -Wl$(comma)--hash-style=sysv)
17ccflags-y += -fPIC -Wl,-shared -g
18
19# Disable gcov profiling for VDSO code
20GCOV_PROFILE := n
21
22
23obj-y += vdso.o
24extra-y += vdso.lds
25CPPFLAGS_vdso.lds += -P -C -U$(ARCH)
26
27# Force dependency
28$(obj)/vdso.o : $(obj)/vdso.so
29
30# Link rule for the .so file, .lds has to be first
31$(obj)/vdso.so.dbg: $(src)/vdso.lds $(obj-vdso)
32	$(call if_changed,vdsold)
33
34
35# Strip rule for the .so file
36$(obj)/%.so: OBJCOPYFLAGS := -S
37$(obj)/%.so: $(obj)/%.so.dbg FORCE
38	$(call if_changed,objcopy)
39
40# Generate VDSO offsets using helper script
41gen-vdsosym := $(srctree)/$(src)/gen_vdso_offsets.sh
42quiet_cmd_vdsosym = VDSOSYM $@
43define cmd_vdsosym
44	$(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@
45endef
46
47include/generated/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE
48	$(call if_changed,vdsosym)
49
50
51
52# Assembly rules for the .S files
53
54sigreturn.o : sigreturn.S
55	$(call if_changed_dep,vdsoas)
56
57note.o : note.S
58	$(call if_changed_dep,vdsoas)
59
60datapage.o : datapage.S
61	$(call if_changed_dep,vdsoas)
62
63gettimeofday.o : gettimeofday.c FORCE
64	$(call if_changed_dep,vdsocc)
65
66# Actual build commands
67quiet_cmd_vdsold = VDSOL   $@
68      cmd_vdsold = $(CC) $(c_flags) -Wl,-n -Wl,-T $^ -o $@
69quiet_cmd_vdsoas = VDSOA   $@
70      cmd_vdsoas = $(CC) $(a_flags) -c -o $@ $<
71quiet_cmd_vdsocc = VDSOA   $@
72      cmd_vdsocc = $(CC) $(c_flags) -c -o $@ $<
73
74# Install commands for the unstripped file
75quiet_cmd_vdso_install = INSTALL $@
76      cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@
77
78vdso.so: $(obj)/vdso.so.dbg
79	@mkdir -p $(MODLIB)/vdso
80	$(call cmd,vdso_install)
81
82vdso_install: vdso.so
83