ipc: move IPC payload write to SOF Zephyr IPC client code

In commit 7ba1a08 ("ipc4: add support for ipc4 boot message and
data"), ipc_prepare_to_send() function was added to prepare the IPC
client code to handle multiple IPC versions. This function has however
not been used in all IPC client code in SOF, and when Intel IPC3 support
was removed, only remaining usage is in ipc-zephyr.c.

As usage is limited, change the semantics of ipc_prepare_to_send()
to only modify the header fields (e.g. for IPC4 set the extension
field), but remove the code to write payload to mailbox. Instead
move this code to ipc-zephyr.c. This will allow to move the payload
handling later to Zephyr drivers, and out from common codec.

Signed-off-by: Kai Vehmanen <[email protected]>

Author: kv2019i

src/ipc/ipc-zephyr.c

@@ -328,6 +328,9 @@ int ipc_platform_send_msg(const struct ipc_msg *msg)
 	/* prepare the message and copy to mailbox */
 	struct ipc_cmd_hdr *hdr = ipc_prepare_to_send(msg);
 
+	if (msg->tx_size)
+		mailbox_dspbox_write(0, (uint32_t *)msg->tx_data, msg->tx_size);
+
 	return ipc_send_message(hdr->pri, hdr->ext);
 }
 

src/ipc/ipc3/handler.c

@@ -1500,8 +1500,6 @@ struct ipc_cmd_hdr *ipc_prepare_to_send(const struct ipc_msg *msg)
 	hdr[0] = msg->header;
 	hdr[1] = 0;
 
-	mailbox_dspbox_write(0, msg->tx_data, msg->tx_size);
-
 	return ipc_to_hdr(hdr);
 }
 

src/ipc/ipc4/handler.c

@@ -1592,9 +1592,6 @@ struct ipc_cmd_hdr *ipc_prepare_to_send(const struct ipc_msg *msg)
 	msg_data.msg_out.pri = msg->header;
 	msg_data.msg_out.ext = msg->extension;
 
-	if (msg->tx_size)
-		mailbox_dspbox_write(0, (uint32_t *)msg->tx_data, msg->tx_size);
-
 	return &msg_data.msg_out;
 }