layerscape: Initial TF-A support for LS1043ardb

This patch introduce TF-A support for NXP's ls1043a platform.
more details information of ls1043a chip and ls1043ardb board
can be found at docs/plat/ls1043a.rst.

Boot sequence on ls1043a is: bootrom loads bl1 firstly, then bl1
loads bl2, bl2 will load bl31, bl32 and bl33, bl31 will boot
bl32(tee os) and bl33(u-boot or uefi), bl33 boot Linux kernel.

Now TF-A on ls1043ardb platform has the following features in this patch:
	* Support boot from Nor flash.
	* TF-A can boot bl33 which runs in el2 of non-secure world.
	* TF-A boot OPTee OS.
	* Support PSCI

Signed-off-by: Jiafei Pan <Jiafei.Pan@nxp.com>
Signed-off-by: Chenyin.Ha <Chenyin.Ha@nxp.com>
Signed-off-by: Chenhui Zhao <chenhui.zhao@nxp.com>
Signed-off-by: jiaheng.fan <jiaheng.fan@nxp.com>
Signed-off-by: Wen He <wen.he_1@nxp.com>
diff --git a/plat/layerscape/common/ns_access.c b/plat/layerscape/common/ns_access.c
new file mode 100644
index 0000000..e1daaed
--- /dev/null
+++ b/plat/layerscape/common/ns_access.c
@@ -0,0 +1,37 @@
+/*
+ * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <mmio.h>
+#include <endian.h>
+#include <debug.h>
+#include "ns_access.h"
+#include "platform_def.h"
+
+static void enable_devices_ns_access(struct csu_ns_dev *ns_dev, uint32_t num)
+{
+	uint32_t *base = (uint32_t *)CONFIG_SYS_FSL_CSU_ADDR;
+	uint32_t *reg;
+	uint32_t val;
+	int i;
+
+	for (i = 0; i < num; i++) {
+		reg = base + ns_dev[i].ind / 2;
+		val = be32toh(mmio_read_32((uintptr_t)reg));
+		if (ns_dev[i].ind % 2 == 0) {
+			val &= 0x0000ffff;
+			val |= ns_dev[i].val << 16;
+		} else {
+			val &= 0xffff0000;
+			val |= ns_dev[i].val;
+		}
+		mmio_write_32((uintptr_t)reg, htobe32(val));
+	}
+}
+
+void enable_layerscape_ns_access(void)
+{
+	enable_devices_ns_access(ns_dev, ARRAY_SIZE(ns_dev));
+}