# SPDX-License-Identifier: GPL-2.0-only
#
# Building a vDSO image for AArch64.
#
# Author: Will Deacon <will.deacon@arm.com>
# Heavily based on the vDSO Makefiles for other archs.
#

obj-vdso := note.o datapage.o sigreturn.o gettimeofday.o

# Build rules
targets := $(obj-vdso) vdso.so vdso.so.dbg
obj-vdso := $(addprefix $(obj)/, $(obj-vdso))

ccflags-y := -shared -fno-common -fno-builtin -nostdlib -fPIC -Wl,-shared -g \
	-Wl,-soname=linux-vdso.so.1 -Wl,--hash-style=sysv

# Disable gcov profiling for VDSO code
GCOV_PROFILE := n


obj-y += vdso.o
targets += vdso.lds
CPPFLAGS_vdso.lds += -P -C -U$(ARCH)

# Force dependency
$(obj)/vdso.o : $(obj)/vdso.so

# Link rule for the .so file, .lds has to be first
$(obj)/vdso.so.dbg: $(obj)/vdso.lds $(obj-vdso) FORCE
	$(call if_changed,vdsold)


# Strip rule for the .so file
$(obj)/%.so: OBJCOPYFLAGS := -S
$(obj)/%.so: $(obj)/%.so.dbg FORCE
	$(call if_changed,objcopy)

# Generate VDSO offsets using helper script
gen-vdsosym := $(srctree)/$(src)/gen_vdso_offsets.sh
quiet_cmd_vdsosym = VDSOSYM $@
      cmd_vdsosym = $(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@

include/generated/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE
	$(call if_changed,vdsosym)


# Assembly rules for the .S files

sigreturn.o : sigreturn.S
	$(call if_changed_dep,vdsoas)

note.o : note.S
	$(call if_changed_dep,vdsoas)

datapage.o : datapage.S
	$(call if_changed_dep,vdsoas)

gettimeofday.o : gettimeofday.c FORCE
	$(call if_changed_dep,vdsocc)

# Actual build commands
quiet_cmd_vdsold = VDSOL   $@
      cmd_vdsold = $(CC) $(c_flags) -Wl,-n -Wl,-T $(real-prereqs) -o $@
quiet_cmd_vdsoas = VDSOA   $@
      cmd_vdsoas = $(CC) $(a_flags) -c -o $@ $<
quiet_cmd_vdsocc = VDSOA   $@
      cmd_vdsocc = $(CC) $(c_flags) -c -o $@ $<

# Install commands for the unstripped file
quiet_cmd_vdso_install = INSTALL $@
      cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@

vdso.so: $(obj)/vdso.so.dbg
	@mkdir -p $(MODLIB)/vdso
	$(call cmd,vdso_install)

vdso_install: vdso.so