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/versal_net_gicv3.c b/plat/xilinx/versal_net/versal_net_gicv3.c
new file mode 100644
index 0000000..028c187
--- /dev/null
+++ b/plat/xilinx/versal_net/versal_net_gicv3.c
@@ -0,0 +1,136 @@
+/*
+ * Copyright (c) 2018-2019, 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 <common/interrupt_props.h>
+#include <drivers/arm/gicv3.h>
+#include <lib/utils.h>
+#include <plat/common/platform.h>
+
+#include <plat_private.h>
+#include <platform_def.h>
+
+/******************************************************************************
+ * The following functions are defined as weak to allow a platform to override
+ * the way the GICv3 driver is initialised and used.
+ *****************************************************************************/
+#pragma weak plat_versal_net_gic_driver_init
+#pragma weak plat_versal_net_gic_init
+#pragma weak plat_versal_net_gic_cpuif_enable
+#pragma weak plat_versal_net_gic_pcpu_init
+
+/* The GICv3 driver only needs to be initialized in EL3 */
+static uintptr_t rdistif_base_addrs[PLATFORM_CORE_COUNT];
+
+static const uintptr_t gicr_base_addrs[2] = {
+	PLAT_VERSAL_NET_GICR_BASE,	/* GICR Base address of the primary CPU */
+	0U				/* Zero Termination */
+};
+
+/* List of zero terminated GICR frame addresses which CPUs will probe */
+static const uintptr_t *gicr_frames;
+
+static const interrupt_prop_t versal_net_interrupt_props[] = {
+	PLAT_VERSAL_NET_G1S_IRQ_PROPS(INTR_GROUP1S),
+	PLAT_VERSAL_NET_G0_IRQ_PROPS(INTR_GROUP0)
+};
+
+/*
+ * MPIDR hashing function for translating MPIDRs read from GICR_TYPER register
+ * to core position.
+ *
+ * Calculating core position is dependent on MPIDR_EL1.MT bit. However, affinity
+ * values read from GICR_TYPER don't have an MT field. To reuse the same
+ * translation used for CPUs, we insert MT bit read from the PE's MPIDR into
+ * that read from GICR_TYPER.
+ *
+ * Assumptions:
+ *
+ *   - All CPUs implemented in the system have MPIDR_EL1.MT bit set;
+ *   - No CPUs implemented in the system use affinity level 3.
+ */
+static uint32_t versal_net_gicv3_mpidr_hash(u_register_t mpidr)
+{
+	mpidr |= (read_mpidr_el1() & MPIDR_MT_MASK);
+	return plat_core_pos_by_mpidr(mpidr);
+}
+
+static const gicv3_driver_data_t versal_net_gic_data __unused = {
+	.gicd_base = PLAT_VERSAL_NET_GICD_BASE,
+	.gicr_base = 0U,
+	.interrupt_props = versal_net_interrupt_props,
+	.interrupt_props_num = ARRAY_SIZE(versal_net_interrupt_props),
+	.rdistif_num = PLATFORM_CORE_COUNT,
+	.rdistif_base_addrs = rdistif_base_addrs,
+	.mpidr_to_core_pos = versal_net_gicv3_mpidr_hash
+};
+
+void __init plat_versal_net_gic_driver_init(void)
+{
+	/*
+	 * The GICv3 driver is initialized in EL3 and does not need
+	 * to be initialized again in SEL1. This is because the S-EL1
+	 * can use GIC system registers to manage interrupts and does
+	 * not need GIC interface base addresses to be configured.
+	 */
+#if IMAGE_BL31
+	gicv3_driver_init(&versal_net_gic_data);
+	gicr_frames = gicr_base_addrs;
+
+	if (gicv3_rdistif_probe(gicr_frames[0]) == -1) {
+		ERROR("No GICR base frame found for Primary CPU\n");
+		panic();
+	}
+#endif
+}
+
+/******************************************************************************
+ * Versal NET common helper to initialize the GIC. Only invoked by BL31
+ *****************************************************************************/
+void __init plat_versal_net_gic_init(void)
+{
+	gicv3_distif_init();
+	gicv3_rdistif_init(plat_my_core_pos());
+	gicv3_cpuif_enable(plat_my_core_pos());
+}
+
+/******************************************************************************
+ * Versal NET common helper to enable the GIC CPU interface
+ *****************************************************************************/
+void plat_versal_net_gic_cpuif_enable(void)
+{
+	gicv3_cpuif_enable(plat_my_core_pos());
+}
+
+/******************************************************************************
+ * Versal NET common helper to initialize the per-cpu redistributor interface in
+ * GICv3
+ *****************************************************************************/
+void plat_versal_net_gic_pcpu_init(void)
+{
+	int32_t result;
+	const uintptr_t *plat_gicr_frames = gicr_frames;
+
+	do {
+		result = gicv3_rdistif_probe(*plat_gicr_frames);
+
+		/* If the probe is successful, no need to proceed further */
+		if (result == 0) {
+			break;
+		}
+
+		plat_gicr_frames++;
+	} while (*plat_gicr_frames != 0U);
+
+	if (result == -1) {
+		ERROR("No GICR base frame found for CPU 0x%lx\n", read_mpidr());
+		panic();
+	}
+
+	gicv3_rdistif_init(plat_my_core_pos());
+}