feat(versal-net): add support for Xilinx Versal NET platform

New SoC is a78 based with gicv3 and uart over pl011. Communication
interfaces are similar to Versal platform. System starts with Xilinx PLM
firmware which loads TF-A(bl31) to DDR, which is already configured, and
jumps to it. PLM also prepare handoff structure for TF-A with information
what components were load and flags which indicate which EL level SW should
be started.

Signed-off-by: Michal Simek <michal.simek@amd.com>
Signed-off-by: Akshay Belsare <Akshay.Belsare@amd.com>
Change-Id: I2a16c242a77be6c91be3d198727dc3b9bbb97410
diff --git a/plat/xilinx/versal_net/plat_topology.c b/plat/xilinx/versal_net/plat_topology.c
new file mode 100644
index 0000000..7f985b0
--- /dev/null
+++ b/plat/xilinx/versal_net/plat_topology.c
@@ -0,0 +1,63 @@
+/*
+ * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2018-2022, Xilinx, Inc. All rights reserved.
+ * Copyright (C) 2022, Advanced Micro Devices, Inc. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <common/debug.h>
+#include <plat/common/platform.h>
+
+#include <plat_private.h>
+#include <platform_def.h>
+
+static const uint8_t plat_power_domain_tree_desc[] = {
+	/* Number of root nodes */
+	1,
+	/* Number of clusters */
+	PLATFORM_CLUSTER_COUNT,
+	/* Number of children for the first cluster node */
+	PLATFORM_CORE_COUNT_PER_CLUSTER,
+	/* Number of children for the second cluster node */
+	PLATFORM_CORE_COUNT_PER_CLUSTER,
+	/* Number of children for the third cluster node */
+	PLATFORM_CORE_COUNT_PER_CLUSTER,
+	/* Number of children for the fourth cluster node */
+	PLATFORM_CORE_COUNT_PER_CLUSTER,
+};
+
+const uint8_t *plat_get_power_domain_tree_desc(void)
+{
+	return plat_power_domain_tree_desc;
+}
+
+/*******************************************************************************
+ * This function implements a part of the critical interface between the psci
+ * generic layer and the platform that allows the former to query the platform
+ * to convert an MPIDR to a unique linear index. An error code (-1) is returned
+ * in case the MPIDR is invalid.
+ ******************************************************************************/
+int32_t plat_core_pos_by_mpidr(u_register_t mpidr)
+{
+	uint32_t cluster_id, cpu_id;
+
+	mpidr &= MPIDR_AFFINITY_MASK;
+
+	cluster_id = MPIDR_AFFLVL2_VAL(mpidr);
+	cpu_id = MPIDR_AFFLVL1_VAL(mpidr);
+
+	if (cluster_id >= PLATFORM_CLUSTER_COUNT) {
+		return -3;
+	}
+
+	/*
+	 * Validate cpu_id by checking whether it represents a CPU in
+	 * one of the two clusters present on the platform.
+	 */
+	if (cpu_id >= PLATFORM_CORE_COUNT_PER_CLUSTER) {
+		return -1;
+	}
+
+	return (cpu_id + (cluster_id * PLATFORM_CORE_COUNT_PER_CLUSTER));
+}