Unfortunately there is no "easy way" on TurboTax, unless your brokerage has a tool for this. You can however, add up your cost basis for all income-generating securities (Which is considered dividends or interest) and as long as they do not exceed the amount you've borrowed and are within reasonable accuracy to how much you've spent with the money borrowed, you will be fine. For more information, click here: TurboTax - Is Interest Deductible?
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