ARM: rmobile: Add support R-Car Generation 3

This adds supporting R-Car Generation 3 (Gen3) as Renesas ARM64 SoC.

Signed-off-by: Hiroyuki Yokoyama <hiroyuki.yokoyama.vx@renesas.com>
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
diff --git a/arch/arm/mach-rmobile/lowlevel_init_gen3.S b/arch/arm/mach-rmobile/lowlevel_init_gen3.S
new file mode 100644
index 0000000..88ff56e
--- /dev/null
+++ b/arch/arm/mach-rmobile/lowlevel_init_gen3.S
@@ -0,0 +1,76 @@
+/*
+ * arch/arm/cpu/armv8/rcar_gen3/lowlevel_init.S
+ *	This file is lowlevel initialize routine.
+ *
+ * (C) Copyright 2015 Renesas Electronics Corporation
+ *
+ * This file is based on the arch/arm/cpu/armv8/start.S
+ *
+ * (C) Copyright 2013
+ * David Feng <fenghua@phytium.com.cn>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <asm-offsets.h>
+#include <config.h>
+#include <linux/linkage.h>
+#include <asm/macro.h>
+
+ENTRY(lowlevel_init)
+	mov	x29, lr			/* Save LR */
+
+#ifndef CONFIG_ARMV8_MULTIENTRY
+	/*
+	 * For single-entry systems the lowlevel init is very simple.
+	 */
+	ldr	x0, =GICD_BASE
+	bl	gic_init_secure
+
+#else /* CONFIG_ARMV8_MULTIENTRY is set */
+
+#if defined(CONFIG_GICV2) || defined(CONFIG_GICV3)
+	branch_if_slave x0, 1f
+	ldr	x0, =GICD_BASE
+	bl	gic_init_secure
+1:
+#if defined(CONFIG_GICV3)
+	ldr	x0, =GICR_BASE
+	bl	gic_init_secure_percpu
+#elif defined(CONFIG_GICV2)
+	ldr	x0, =GICD_BASE
+	ldr	x1, =GICC_BASE
+	bl	gic_init_secure_percpu
+#endif
+#endif
+
+	branch_if_master x0, x1, 2f
+
+	/*
+	 * Slave should wait for master clearing spin table.
+	 * This sync prevent salves observing incorrect
+	 * value of spin table and jumping to wrong place.
+	 */
+#if defined(CONFIG_GICV2) || defined(CONFIG_GICV3)
+#ifdef CONFIG_GICV2
+	ldr	x0, =GICC_BASE
+#endif
+	bl	gic_wait_for_interrupt
+#endif
+
+	/*
+	 * All slaves will enter EL2 and optionally EL1.
+	 */
+	bl	armv8_switch_to_el2
+#ifdef CONFIG_ARMV8_SWITCH_TO_EL1
+	bl	armv8_switch_to_el1
+#endif
+
+#endif /* CONFIG_ARMV8_MULTIENTRY */
+
+	bl      s_init
+
+2:
+	mov	lr, x29			/* Restore LR */
+	ret
+ENDPROC(lowlevel_init)