arm64: Turn u-boot.bin back into an ELF file after relocate-rela

While performing relocations on u-boot.bin should be good enough for
booting on real hardware, some simulators insist on booting an ELF file
(and yet don't perform ELF relocations), so convert the relocated
binary back into an ELF file.  This can go away in the future if we
change relocate-rela to operate directly on the ELF file, or if and
when we stop caring about a simulator with this restriction.

Signed-off-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: David Feng <fenghua@phytium.com.cn>

Makefile

@@ -358,6 +358,7 @@ ALL-$(CONFIG_OF_SEPARATE) += $(obj)u-boot.dtb $(obj)u-boot-dtb.bin
 ifneq ($(CONFIG_SPL_TARGET),)
 ALL-$(CONFIG_SPL) += $(obj)$(subst ",,$(CONFIG_SPL_TARGET))
 endif
+ALL-$(CONFIG_REMAKE_ELF) += $(obj)u-boot.elf
 
 # enable combined SPL/u-boot/dtb rules for tegra
 ifneq ($(CONFIG_TEGRA),)
@@ -528,6 +529,18 @@ $(obj)u-boot-img-spl-at-end.bin: $(obj)spl/u-boot-spl.bin $(obj)u-boot.img
 			conv=notrunc 2>/dev/null
 		cat $(obj)u-boot-pad.img $(obj)spl/u-boot-spl.bin > $@
 
+# Create a new ELF from a raw binary file.  This is useful for arm64
+# where static relocation needs to be performed on the raw binary,
+# but certain simulators only accept an ELF file (but don't do the
+# relocation).
+# FIXME refactor dts/Makefile to share target/arch detection
+$(obj)u-boot.elf: $(obj)u-boot.bin
+	@$(OBJCOPY)  -B aarch64 -I binary -O elf64-littleaarch64 \
+		$< $(obj)u-boot-elf.o
+	@$(LD) $(obj)u-boot-elf.o -o $@ \
+		--defsym=_start=$(CONFIG_SYS_TEXT_BASE) \
+		-Ttext=$(CONFIG_SYS_TEXT_BASE)
+
 ifeq ($(CONFIG_SANDBOX),y)
 GEN_UBOOT = \
 		cd $(LNDIR) && $(CC) $(SYMS) -T $(obj)u-boot.lds \