arm64: Add Xilinx ZynqMP support

Add basic Xilinx ZynqMP arm64 support.
Serial and SD is supported.
It supports emulation platfrom ep108 and QEMU.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/arch/arm/cpu/armv8/zynqmp/cpu.c b/arch/arm/cpu/armv8/zynqmp/cpu.c
new file mode 100644
index 0000000..6fae03c
--- /dev/null
+++ b/arch/arm/cpu/armv8/zynqmp/cpu.c
@@ -0,0 +1,28 @@
+/*
+ * (C) Copyright 2014 - 2015 Xilinx, Inc.
+ * Michal Simek <michal.simek@xilinx.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/arch/hardware.h>
+#include <asm/arch/sys_proto.h>
+#include <asm/io.h>
+
+#define ZYNQ_SILICON_VER_MASK	0xF000
+#define ZYNQ_SILICON_VER_SHIFT	12
+
+DECLARE_GLOBAL_DATA_PTR;
+
+unsigned int zynqmp_get_silicon_version(void)
+{
+	gd->cpu_clk = get_tbclk();
+
+	switch (gd->cpu_clk) {
+	case 50000000:
+		return ZYNQMP_CSU_VERSION_QEMU;
+	}
+
+	return ZYNQMP_CSU_VERSION_EP108;
+}