A method and apparatus for efficient operation of an enhanced dedicated channel (E-DCH) are disclosed. A physical layer processing includes computation of various control parameters followed by actual processing of the data to be transmitted. In accordance with the present invention, the computation of the control parameters is performed asynchronously from the associated data operation. A medium access control (MAC) layer provides information needed for computation of the control parameters to the physical layer as early as possible, while the data is being processed in parallel. The provided data includes a hybrid automatic repeat request (H-ARQ) profile, a transport block size, power offset, or the like. By sending this data to the physical layer before MAC-e processing is complete, the latency constraint can be significantly relaxed.