mailbox: arm_mhuv2: Add driver

This adds driver for the ARM MHUv2 (Message Handling Unit) mailbox
controller.

This is based on the accepted DT bindings of the controller and supports
combination of both transport protocols, i.e. doorbell and data-transfer.

Transmitting and receiving data through the mailbox framework is done
through struct arm_mhuv2_mbox_msg.

Based on the initial work done by Morten Borup Petersen from ARM.

Co-developed-by: Tushar Khandelwal <tushar.khandelwal@arm.com>
Signed-off-by: Tushar Khandelwal <tushar.khandelwal@arm.com>
Tested-by: Usama Arif <usama.arif@arm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

1 files changed, 20 insertions, 0 deletions

diff --git a/include/linux/mailbox/arm_mhuv2_message.h b/include/linux/mailbox/arm_mhuv2_message.h
new file mode 100644
index 000000000000..821b9d96daa4
--- /dev/null
+++ b/include/linux/mailbox/arm_mhuv2_message.h
@@ -0,0 +1,20 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ARM MHUv2 Mailbox Message
+ *
+ * Copyright (C) 2020 Arm Ltd.
+ * Copyright (C) 2020 Linaro Ltd.
+ */
+
+#ifndef _LINUX_ARM_MHUV2_MESSAGE_H_
+#define _LINUX_ARM_MHUV2_MESSAGE_H_
+
+#include <linux/types.h>
+
+/* Data structure for data-transfer protocol */
+struct arm_mhuv2_mbox_msg {
+	void *data;
+	size_t len;
+};
+
+#endif /* _LINUX_ARM_MHUV2_MESSAGE_H_ */