feat(rss): add new comms protocols
The current comms protocol (where arguments and return data is embedded
into the MHU message) is now protocol v0. Protocol v1 embeds pointers
into the message, and has the RSS retrieve the data via DMA.
Change-Id: I08d7f09c4eaea673769fde9eee194447a99f1b78
Signed-off-by: Raef Coles <raef.coles@arm.com>
diff --git a/drivers/arm/rss/rss_comms_protocol.h b/drivers/arm/rss/rss_comms_protocol.h
new file mode 100644
index 0000000..9a38057
--- /dev/null
+++ b/drivers/arm/rss/rss_comms_protocol.h
@@ -0,0 +1,67 @@
+/*
+ * Copyright (c) 2022, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ */
+
+#ifndef __RSS_COMMS_PROTOCOL_H__
+#define __RSS_COMMS_PROTOCOL_H__
+
+#include <cdefs.h>
+#include <stdint.h>
+
+#include <psa/client.h>
+#include "rss_comms_protocol_embed.h"
+#include "rss_comms_protocol_pointer_access.h"
+
+enum rss_comms_protocol_version_t {
+ RSS_COMMS_PROTOCOL_EMBED = 0,
+ RSS_COMMS_PROTOCOL_POINTER_ACCESS = 1,
+};
+
+struct __packed serialized_rss_comms_header_t {
+ uint8_t protocol_ver;
+ uint8_t seq_num;
+ uint16_t client_id;
+};
+
+/* MHU message passed from Host to RSS to deliver a PSA client call */
+struct __packed serialized_rss_comms_msg_t {
+ struct serialized_rss_comms_header_t header;
+ union __packed {
+ struct rss_embed_msg_t embed;
+ struct rss_pointer_access_msg_t pointer_access;
+ } msg;
+};
+
+/* MHU reply message to hold the PSA client reply result returned by RSS */
+struct __packed serialized_rss_comms_reply_t {
+ struct serialized_rss_comms_header_t header;
+ union __packed {
+ struct rss_embed_reply_t embed;
+ struct rss_pointer_access_reply_t pointer_access;
+ } reply;
+};
+
+/* in_len and out_len are uint8_ts, therefore if there are more than 255 iovecs
+ * an error may occur.
+ */
+CASSERT(PSA_MAX_IOVEC <= UINT8_MAX, assert_rss_comms_max_iovec_too_large);
+
+psa_status_t rss_protocol_serialize_msg(psa_handle_t handle,
+ int16_t type,
+ const psa_invec *in_vec,
+ uint8_t in_len,
+ const psa_outvec *out_vec,
+ uint8_t out_len,
+ struct serialized_rss_comms_msg_t *msg,
+ size_t *msg_len);
+
+psa_status_t rss_protocol_deserialize_reply(psa_outvec *out_vec,
+ uint8_t out_len,
+ psa_status_t *return_val,
+ const struct serialized_rss_comms_reply_t *reply,
+ size_t reply_size);
+
+#endif /* __RSS_COMMS_PROTOCOL_H__ */