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_embed.h b/drivers/arm/rss/rss_comms_protocol_embed.h
new file mode 100644
index 0000000..6c2a7bd
--- /dev/null
+++ b/drivers/arm/rss/rss_comms_protocol_embed.h
@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) 2022, Arm Limited. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ */
+
+#ifndef __RSS_COMMS_PROTOCOL_EMBED_H__
+#define __RSS_COMMS_PROTOCOL_EMBED_H__
+
+#include <cdefs.h>
+
+#include <initial_attestation.h>
+#include <psa/client.h>
+
+#include <platform_def.h>
+
+/*
+ * In the current implementation the RoT Service request that requires the
+ * biggest message buffer is the RSS_ATTEST_GET_TOKEN. The maximum required
+ * buffer size is calculated based on the platform-specific needs of
+ * this request.
+ */
+#ifndef RSS_COMMS_PAYLOAD_MAX_SIZE
+#define RSS_COMMS_PAYLOAD_MAX_SIZE (PSA_INITIAL_ATTEST_CHALLENGE_SIZE_64 \
+ + PLAT_ATTEST_TOKEN_MAX_SIZE)
+#endif
+
+struct __packed rss_embed_msg_t {
+ psa_handle_t handle;
+ uint32_t ctrl_param; /* type, in_len, out_len */
+ uint16_t io_size[PSA_MAX_IOVEC];
+ uint8_t trailer[RSS_COMMS_PAYLOAD_MAX_SIZE];
+};
+
+struct __packed rss_embed_reply_t {
+ int32_t return_val;
+ uint16_t out_size[PSA_MAX_IOVEC];
+ uint8_t trailer[RSS_COMMS_PAYLOAD_MAX_SIZE];
+};
+
+psa_status_t rss_protocol_embed_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 rss_embed_msg_t *msg,
+ size_t *msg_len);
+
+psa_status_t rss_protocol_embed_deserialize_reply(psa_outvec *out_vec,
+ uint8_t out_len,
+ psa_status_t *return_val,
+ const struct rss_embed_reply_t *reply,
+ size_t reply_size);
+
+#endif /* __RSS_COMMS_PROTOCOL_EMBED_H__ */