Support for NVIDIA's Tegra T210 SoCs

T210 is the latest chip in the Tegra family of SoCs from NVIDIA. It is an
ARM v8 dual-cluster (A57/A53) SoC, with any one of the clusters being active
at a given point in time.

This patch adds support to boot the Trusted Firmware on T210 SoCs. The patch
also adds support to boot secondary CPUs, enter/exit core power states for
all CPUs in the slow/fast clusters. The support to switch between clusters
is still not available in this patch and would be available later.

Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>
diff --git a/plat/nvidia/tegra/common/tegra_topology.c b/plat/nvidia/tegra/common/tegra_topology.c
new file mode 100644
index 0000000..220e697
--- /dev/null
+++ b/plat/nvidia/tegra/common/tegra_topology.c
@@ -0,0 +1,72 @@
+/*
+ * Copyright (c) 2015, ARM Limited and Contributors. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * Neither the name of ARM nor the names of its contributors may be used
+ * to endorse or promote products derived from this software without specific
+ * prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <arch_helpers.h>
+#include <platform_def.h>
+#include <psci.h>
+
+/*******************************************************************************
+ * This function implements a part of the critical interface between the psci
+ * generic layer and the platform to allow the former to detect the platform
+ * topology. psci queries the platform to determine how many affinity instances
+ * are present at a particular level for a given mpidr.
+ ******************************************************************************/
+unsigned int plat_get_aff_count(unsigned int aff_lvl,
+				unsigned long mpidr)
+{
+	switch (aff_lvl) {
+	case MPIDR_AFFLVL2:
+		/* Last supported affinity level */
+		return 1;
+
+	case MPIDR_AFFLVL1:
+		/* Return # of clusters */
+		return PLATFORM_CLUSTER_COUNT;
+
+	case MPIDR_AFFLVL0:
+		/* # of cpus per cluster */
+		return PLATFORM_MAX_CPUS_PER_CLUSTER;
+
+	default:
+		return PSCI_AFF_ABSENT;
+	}
+}
+
+/*******************************************************************************
+ * This function implements a part of the critical interface between the psci
+ * generic layer and the platform to allow the former to detect the state of a
+ * affinity instance in the platform topology. psci queries the platform to
+ * determine whether an affinity instance is present or absent.
+ ******************************************************************************/
+unsigned int plat_get_aff_state(unsigned int aff_lvl,
+				unsigned long mpidr)
+{
+	return (aff_lvl <= MPIDR_AFFLVL2) ? PSCI_AFF_PRESENT : PSCI_AFF_ABSENT;
+}