diff --git a/plat/meson/gxbb/gxbb_mhu.c b/plat/meson/gxbb/gxbb_mhu.c
new file mode 100644
index 0000000..78b895c
--- /dev/null
+++ b/plat/meson/gxbb/gxbb_mhu.c
@@ -0,0 +1,52 @@
+/*
+ * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <bakery_lock.h>
+#include <mmio.h>
+#include <platform_def.h>
+
+static DEFINE_BAKERY_LOCK(mhu_lock);
+
+void mhu_secure_message_start(void)
+{
+	bakery_lock_get(&mhu_lock);
+
+	while (mmio_read_32(GXBB_HIU_MAILBOX_STAT_3) != 0)
+		;
+}
+
+void mhu_secure_message_send(uint32_t msg)
+{
+	mmio_write_32(GXBB_HIU_MAILBOX_SET_3, msg);
+
+	while (mmio_read_32(GXBB_HIU_MAILBOX_STAT_3) != 0)
+		;
+}
+
+uint32_t mhu_secure_message_wait(void)
+{
+	uint32_t val;
+
+	do {
+		val = mmio_read_32(GXBB_HIU_MAILBOX_STAT_0);
+	} while (val == 0);
+
+	return val;
+}
+
+void mhu_secure_message_end(void)
+{
+	mmio_write_32(GXBB_HIU_MAILBOX_CLR_0, 0xFFFFFFFF);
+
+	bakery_lock_release(&mhu_lock);
+}
+
+void mhu_secure_init(void)
+{
+	bakery_lock_init(&mhu_lock);
+
+	mmio_write_32(GXBB_HIU_MAILBOX_CLR_3, 0xFFFFFFFF);
+}