armv8: layerscape: Enable falcon boot

Add jump_to_image_linux() for arm64. Add "noreturn" flag to
armv8_switch_to_el2(). Add hooks to fsl-layerscape to enable falcon
boot.

Signed-off-by: York Sun <york.sun@nxp.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Łukasz Majewski <lukma@denx.de>
Tested-by: Łukasz Majewski <lukma@denx.de>
diff --git a/arch/arm/lib/spl.c b/arch/arm/lib/spl.c
index 27d6682..ab5d227 100644
--- a/arch/arm/lib/spl.c
+++ b/arch/arm/lib/spl.c
@@ -7,6 +7,7 @@
  *
  * SPDX-License-Identifier:	GPL-2.0+
  */
+
 #include <common.h>
 #include <config.h>
 #include <spl.h>
@@ -47,6 +48,15 @@
  * image.
  */
 #ifdef CONFIG_SPL_OS_BOOT
+#ifdef CONFIG_ARM64
+void __noreturn jump_to_image_linux(struct spl_image_info *spl_image)
+{
+	debug("Entering kernel arg pointer: 0x%p\n", spl_image->arg);
+	cleanup_before_linux();
+	armv8_switch_to_el2((u64)spl_image->arg, 0, 0, 0,
+			    spl_image->entry_point, ES_TO_AARCH64);
+}
+#else
 void __noreturn jump_to_image_linux(struct spl_image_info *spl_image)
 {
 	unsigned long machid = 0xffffffff;
@@ -62,4 +72,5 @@
 	cleanup_before_linux();
 	image_entry(0, machid, spl_image->arg);
 }
+#endif	/* CONFIG_ARM64 */
 #endif