Add Xilinx ZynqMP IPI mailbox service

Add IPI mailbox service to manage Xilinx ZynqMP IPI(Inter Processors
Interrupt) access.

Signed-off-by: Wendy Liang <jliang@xilinx.com>
diff --git a/plat/xilinx/zynqmp/ipi_mailbox_service/ipi_mailbox_svc.c b/plat/xilinx/zynqmp/ipi_mailbox_service/ipi_mailbox_svc.c
new file mode 100644
index 0000000..bfc19d3
--- /dev/null
+++ b/plat/xilinx/zynqmp/ipi_mailbox_service/ipi_mailbox_svc.c
@@ -0,0 +1,129 @@
+/*
+ * Copyright (c) 2017, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+/*
+ * Top-level SMC handler for ZynqMP IPI Mailbox doorbell functions.
+ */
+
+#include <bakery_lock.h>
+#include <debug.h>
+#include <errno.h>
+#include <mmio.h>
+#include <runtime_svc.h>
+#include <string.h>
+#include "ipi_mailbox_svc.h"
+#include "../zynqmp_ipi.h"
+#include "../zynqmp_private.h"
+#include "../../../services/spd/trusty/smcall.h"
+
+/*********************************************************************
+ * Macros definitions
+ ********************************************************************/
+
+/* IPI SMC calls macros: */
+#define IPI_SMC_OPEN_IRQ_MASK		0x00000001U /* IRQ enable bit in IPI
+						     * open SMC call
+						     */
+#define IPI_SMC_NOTIFY_BLOCK_MASK	0x00000001U /* Flag to indicate if
+						     * IPI notification needs
+						     * to be blocking.
+						     */
+#define IPI_SMC_ENQUIRY_DIRQ_MASK	0x00000001U /* Flag to indicate if
+						     * notification interrupt
+						     * to be disabled.
+						     */
+#define IPI_SMC_ACK_EIRQ_MASK		0x00000001U /* Flag to indicate if
+						     * notification interrupt
+						     * to be enable.
+						     */
+
+#define UNSIGNED32_MASK			0xFFFFFFFFU /* 32bit mask */
+
+/**
+ * ipi_smc_handler() - SMC handler for IPI SMC calls
+ *
+ * @smc_fid - Function identifier
+ * @x1 - x4 - Arguments
+ * @cookie  - Unused
+ * @handler - Pointer to caller's context structure
+ *
+ * @return  - Unused
+ *
+ * Determines that smc_fid is valid and supported PM SMC Function ID from the
+ * list of pm_api_ids, otherwise completes the request with
+ * the unknown SMC Function ID
+ *
+ * The SMC calls for PM service are forwarded from SIP Service SMC handler
+ * function with rt_svc_handle signature
+ */
+uint64_t ipi_smc_handler(uint32_t smc_fid, uint64_t x1, uint64_t x2,
+			 uint64_t x3, uint64_t x4, void *cookie,
+			 void *handle, uint64_t flags)
+{
+	int ret;
+	uint32_t ipi_local_id;
+	uint32_t ipi_remote_id;
+	unsigned int is_secure;
+
+	ipi_local_id = x1 & UNSIGNED32_MASK;
+	ipi_remote_id = x2 & UNSIGNED32_MASK;
+
+	if (SMC_ENTITY(smc_fid) >= SMC_ENTITY_TRUSTED_APP)
+		is_secure = 1;
+	else
+		is_secure = 0;
+
+	/* Validate IPI mailbox access */
+	ret = ipi_mb_validate(ipi_local_id, ipi_remote_id, is_secure);
+	if (ret)
+		SMC_RET1(handle, ret);
+
+	switch (SMC_FUNCTION(smc_fid)) {
+	case IPI_MAILBOX_OPEN:
+		ipi_mb_open(ipi_local_id, ipi_remote_id);
+		SMC_RET1(handle, 0);
+	case IPI_MAILBOX_RELEASE:
+		ipi_mb_release(ipi_local_id, ipi_remote_id);
+		SMC_RET1(handle, 0);
+	case IPI_MAILBOX_STATUS_ENQUIRY:
+	{
+		int disable_irq;
+
+		disable_irq = (x3 & IPI_SMC_ENQUIRY_DIRQ_MASK) ? 1 : 0;
+		ret = ipi_mb_enquire_status(ipi_local_id, ipi_remote_id);
+		if ((ret & IPI_MB_STATUS_RECV_PENDING) && disable_irq)
+			ipi_mb_disable_irq(ipi_local_id, ipi_remote_id);
+		SMC_RET1(handle, ret);
+	}
+	case IPI_MAILBOX_NOTIFY:
+	{
+		uint32_t is_blocking;
+
+		is_blocking = (x3 & IPI_SMC_NOTIFY_BLOCK_MASK) ? 1 : 0;
+		ipi_mb_notify(ipi_local_id, ipi_remote_id, is_blocking);
+		SMC_RET1(handle, 0);
+	}
+	case IPI_MAILBOX_ACK:
+	{
+		int enable_irq;
+
+		enable_irq = (x3 & IPI_SMC_ACK_EIRQ_MASK) ? 1 : 0;
+		ipi_mb_ack(ipi_local_id, ipi_remote_id);
+		if (enable_irq)
+			ipi_mb_enable_irq(ipi_local_id, ipi_remote_id);
+		SMC_RET1(handle, 0);
+	}
+	case IPI_MAILBOX_ENABLE_IRQ:
+		ipi_mb_enable_irq(ipi_local_id, ipi_remote_id);
+		SMC_RET1(handle, 0);
+	case IPI_MAILBOX_DISABLE_IRQ:
+		ipi_mb_disable_irq(ipi_local_id, ipi_remote_id);
+		SMC_RET1(handle, 0);
+	default:
+		WARN("Unimplemented IPI service call: 0x%x\n", smc_fid);
+		SMC_RET1(handle, SMC_UNK);
+	}
+}