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diff --git a/drivers/mailbox/include/mailbox.hpp b/drivers/mailbox/include/mailbox.hpp
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+++ b/drivers/mailbox/include/mailbox.hpp
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+/*
+ * Copyright (c) 2020-2021 Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the License); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an AS IS BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef MAILBOX_HPP
+#define MAILBOX_HPP
+
+#include <cstddef>
+#include <cstdint>
+#include <list>
+
+namespace Mailbox {
+
+/**
+ * The Mailbox parent class
+ *
+ * Intended to be implemented by a driver subclass, see MHU_v2 driver as example.
+ */
+class Mailbox {
+public:
+    /**
+     * Constructor/Destructor
+     */
+    Mailbox();
+    virtual ~Mailbox();
+
+    /**
+     * Intended to trigger an interrupt to an external block
+     * MUST be implemented by subclass.
+     */
+    virtual bool sendMessage() = 0;
+
+    /**
+     * Intended to be called when Cortex M has received an
+     * interrupt/event from mailbox/mhu. If an interrupt needs to be cleared,
+     * this is a good place to do that. MUST call notify().
+     * MUST be implemented by subclass.
+     */
+    virtual void handleMessage() = 0;
+
+    /**
+     * Can be used to verify that hardware versions match expected versions
+     * CAN be implemented by subclass, optional. Default impl returns true.
+     */
+    virtual bool verifyHardware();
+
+    /**
+     * Function signature for callbacks
+     */
+    typedef void (*CallbackFptr)(void *userArg);
+
+    /**
+     * Register a callback to be called when a message is received.
+     */
+    void registerCallback(CallbackFptr callback, void *userArg);
+
+    /**
+     * Remove a specific callback from the callback list.
+     */
+    void deregisterCallback(CallbackFptr callback, void *userArg);
+
+protected:
+    /**
+     * Calls every registered callback when a message has been received.
+     */
+    void notify();
+
+    /**
+     * Helper functions
+     */
+    uint32_t read32(volatile uint32_t *baseAddr, const uint32_t offset);
+    void write32(volatile uint32_t *baseAddr, const uint32_t offset, const uint32_t value);
+
+private:
+    struct Callback {
+        bool operator==(const Callback &b) const;
+        CallbackFptr callback;
+        void *userArg;
+    };
+
+    std::list<Callback> callbacks;
+};
+
+} // namespace Mailbox
+
+#endif