You realize that Adam was punished because he disobyed and ate, not just because he ate of the tree, right?
God gave Adam everythign and put one little condition, don't eat of the tree or you will die.
Adam ate, God punished him with mortality.
Adam died.
Adam's free will was he did what he did even KNOWING the consequences.
God's omniscience was knowing the outcome of whichever decision Adam could have made.