drivers: mspi: RX no copy - drivers

Added no copy functionality to RX.

Signed-off-by: Michal Frankiewicz <[email protected]>

Author: mif1-nordic

drivers/mspi/mspi_nrfe.c

@@ -526,7 +526,7 @@ static int xfer_packet(struct mspi_xfer_packet *packet, uint32_t timeout)
 	nrfe_mspi_opcode_t opcode = (packet->dir == MSPI_RX) ? NRFE_MSPI_TXRX : NRFE_MSPI_TX;
 
 #ifdef CONFIG_MSPI_NRFE_IPC_NO_COPY
-	/* Check for alignment problems. */
+	/* In case of buffer alignment problems: create correctly aligned temporary buffer. */
 	uint32_t len = ((uint32_t)packet->data_buf) % sizeof(uint32_t) != 0
 			       ? sizeof(nrfe_mspi_xfer_packet_msg_t) + packet->num_bytes
 			       : sizeof(nrfe_mspi_xfer_packet_msg_t);
@@ -542,10 +542,14 @@ static int xfer_packet(struct mspi_xfer_packet *packet, uint32_t timeout)
 	xfer_packet->num_bytes = packet->num_bytes;
 
 #ifdef CONFIG_MSPI_NRFE_IPC_NO_COPY
-	/* Check for alignlemt problems. */
+	/* In case of buffer alignment problems: fill temporary buffer with TX data and
+	 * set it as packet data.
+	 */
 	if (((uint32_t)packet->data_buf) % sizeof(uint32_t) != 0) {
-		memcpy((void *)(buffer + sizeof(nrfe_mspi_xfer_packet_msg_t)),
-		       (void *)packet->data_buf, packet->num_bytes);
+		if (packet->dir == MSPI_TX) {
+			memcpy((void *)(buffer + sizeof(nrfe_mspi_xfer_packet_msg_t)),
+			       (void *)packet->data_buf, packet->num_bytes);
+		}
 		xfer_packet->data = buffer + sizeof(nrfe_mspi_xfer_packet_msg_t);
 	} else {
 		xfer_packet->data = packet->data_buf;
@@ -557,20 +561,39 @@ static int xfer_packet(struct mspi_xfer_packet *packet, uint32_t timeout)
 	rc = send_data(xfer_packet->opcode, xfer_packet, len);
 
 	/* Wait for the transfer to complete and receive data. */
-	if ((packet->dir == MSPI_RX) && (ipc_receive_buffer != NULL) && (ipc_received > 0)) {
-		/*
-		 * It is not possible to check whether received data is valid, so packet->num_bytes
-		 * should always be equal to ipc_received. If it is not, then something went wrong.
+	if (packet->dir == MSPI_RX) {
+
+		/* In case of CONFIG_MSPI_NRFE_IPC_NO_COPY ipc_received if equal to 0 because
+		 * packet buffer address was passed to vpr and data was written directly there.
+		 * So there is no way of checking how much data was written.
+		 */
+#ifdef CONFIG_MSPI_NRFE_IPC_NO_COPY
+		/* In case of buffer alignment problems: copy received data from temporary buffer
+		 * back to users buffer.
 		 */
-		if (packet->num_bytes != ipc_received) {
-			rc = -EIO;
-		} else {
-			memcpy((void *)packet->data_buf, (void *)ipc_receive_buffer, ipc_received);
+		if (((uint32_t)packet->data_buf) % sizeof(uint32_t) != 0) {
+			memcpy((void *)packet->data_buf, (void *)xfer_packet->data,
+			       packet->num_bytes);
 		}
+#else
+		if ((ipc_receive_buffer != NULL) && (ipc_received > 0)) {
+			/*
+			 * It is not possible to check whether received data is valid, so
+			 * packet->num_bytes should always be equal to ipc_received. If it is not,
+			 * then something went wrong.
+			 */
+			if (packet->num_bytes != ipc_received) {
+				rc = -EIO;
+			} else {
+				memcpy((void *)packet->data_buf, (void *)ipc_receive_buffer,
+				       ipc_received);
+			}
 
-		/* Clear the receive buffer pointer and size */
-		ipc_receive_buffer = NULL;
-		ipc_received = 0;
+			/* Clear the receive buffer pointer and size */
+			ipc_receive_buffer = NULL;
+			ipc_received = 0;
+		}
+#endif
 	}
 
 	return rc;