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Change-Id: I14b6becc908a0ac215769c32ee9c43db192ae6c8
diff --git a/kernel/ethosu_mailbox.h b/kernel/ethosu_mailbox.h
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+/*
+ * (C) COPYRIGHT 2020 ARM Limited. All rights reserved.
+ *
+ * This program is free software and is provided to you under the terms of the
+ * GNU General Public License version 2 as published by the Free Software
+ * Foundation, and any use by you of this program is subject to the terms
+ * of such GNU licence.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, you can access it online at
+ * http://www.gnu.org/licenses/gpl-2.0.html.
+ *
+ * SPDX-License-Identifier: GPL-2.0-only
+ */
+
+#ifndef ETHOSU_MAILBOX_H
+#define ETHOSU_MAILBOX_H
+
+/****************************************************************************
+ * Includes
+ ****************************************************************************/
+
+#include <linux/types.h>
+#include <linux/mailbox_client.h>
+#include <linux/workqueue.h>
+
+/****************************************************************************
+ * Types
+ ****************************************************************************/
+
+struct device;
+struct ethosu_buffer;
+struct ethosu_device;
+struct ethosu_core_msg;
+struct ethosu_core_queue;
+struct resource;
+
+typedef void (*ethosu_mailbox_cb)(void *user_arg);
+
+struct ethosu_mailbox {
+	struct device            *dev;
+	struct workqueue_struct  *wq;
+	struct work_struct       work;
+	struct ethosu_core_queue __iomem *in_queue;
+	struct ethosu_core_queue __iomem *out_queue;
+	struct mbox_client       client;
+	struct mbox_chan         *rx;
+	struct mbox_chan         *tx;
+	ethosu_mailbox_cb        callback;
+	void                     *user_arg;
+};
+
+/****************************************************************************
+ * Functions
+ ****************************************************************************/
+
+/**
+ * ethosu_mailbox_init() - Initialize mailbox
+ *
+ * Return: 0 on success, else error code.
+ */
+int ethosu_mailbox_init(struct ethosu_mailbox *mbox,
+			struct device *dev,
+			struct resource *in_queue,
+			struct resource *out_queue,
+			ethosu_mailbox_cb callback,
+			void *user_arg);
+
+/**
+ * ethosu_mailbox_deinit() - Deinitialize mailbox
+ */
+void ethosu_mailbox_deinit(struct ethosu_mailbox *mbox);
+
+/**
+ * ethosu_mailbox_read() - Read message from mailbox
+ *
+ * Return: 0 message read, else error code.
+ */
+int ethosu_mailbox_read(struct ethosu_mailbox *mbox,
+			struct ethosu_core_msg *header,
+			void *data,
+			size_t length);
+
+/**
+ * ethosu_mailbox_ping() - Send ping message
+ *
+ * Return: 0 on success, else error code.
+ */
+int ethosu_mailbox_ping(struct ethosu_mailbox *mbox);
+
+/**
+ * ethosu_mailbox_inference() - Send inference
+ *
+ * Return: 0 on success, else error code.
+ */
+int ethosu_mailbox_inference(struct ethosu_mailbox *mbox,
+			     void *user_arg,
+			     struct ethosu_buffer *ifm,
+			     struct ethosu_buffer *ofm,
+			     struct ethosu_buffer *network);
+
+#endif /* ETHOSU_MAILBOX_H */