(Image source: cruiselawnews) Shares of Carnival Corporation (NYSE:CCL), the cruise line operator are trading higher this morning on an upgrade from Credit Suisse. Credit Suisse upgraded the cruise liner to outperform from neutral. The price target was also increased to $43 a share from $30. Credit Suisse cited Carnival’s upbeat earnings outlook released yesterday as a reason for the upgrade. UBS also has a buy rating on the stock.