plat/arm: Introduce TC0 platform

This patch adds support for Total Compute (TC0) platform. It is an
initial port and additional features are expected to be added later.

TC0 has a SCP which brings the primary Cortex-A out of reset
which starts executing BL1. TF-A optionally authenticates the SCP
ram-fw available in FIP and makes it available for SCP to copy.

Some of the major features included and tested in this platform
port include TBBR, PSCI, MHUv2 and DVFS.

Change-Id: I1675e9d200ca7687c215009eef483d9b3ee764ef
Signed-off-by: Usama Arif <usama.arif@arm.com>
diff --git a/plat/arm/board/tc0/tc0_bl31_setup.c b/plat/arm/board/tc0/tc0_bl31_setup.c
new file mode 100644
index 0000000..b91b11c
--- /dev/null
+++ b/plat/arm/board/tc0/tc0_bl31_setup.c
@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2020, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <assert.h>
+
+#include <libfdt.h>
+#include <tc0_plat.h>
+
+#include <common/bl_common.h>
+#include <common/debug.h>
+#include <drivers/arm/css/css_mhu_doorbell.h>
+#include <drivers/arm/css/scmi.h>
+#include <plat/arm/common/plat_arm.h>
+#include <plat/common/platform.h>
+
+static scmi_channel_plat_info_t tc0_scmi_plat_info[] = {
+	{
+		.scmi_mbx_mem = CSS_SCMI_PAYLOAD_BASE,
+		.db_reg_addr = PLAT_CSS_MHU_BASE + SENDER_REG_SET(0),
+		.db_preserve_mask = 0xfffffffe,
+		.db_modify_mask = 0x1,
+		.ring_doorbell = &mhuv2_ring_doorbell,
+	}
+};
+
+void bl31_platform_setup(void)
+{
+	tc0_bl31_common_platform_setup();
+}
+
+scmi_channel_plat_info_t *plat_css_get_scmi_info(int channel_id)
+{
+
+	return &tc0_scmi_plat_info[channel_id];
+
+}
+
+void bl31_early_platform_setup2(u_register_t arg0, u_register_t arg1,
+				u_register_t arg2, u_register_t arg3)
+{
+	arm_bl31_early_platform_setup((void *)arg0, arg1, arg2, (void *)arg3);
+}
+
+void tc0_bl31_common_platform_setup(void)
+{
+	arm_bl31_platform_setup();
+}
+
+const plat_psci_ops_t *plat_arm_psci_override_pm_ops(plat_psci_ops_t *ops)
+{
+	return css_scmi_override_pm_ops(ops);
+}