Aravind,
The C6454 has a power consumption App Note and Spreadsheet at: http://www.ti.com/litv/pdf/spraae8b and http://www.ti.com/litv/zip/spraae8b. All power consumed must be dissipated as heat. The Data Manual http://www.ti.com/lit/gpn/tms320c6454 shows the thermal properties of the package in Section 8. Thermal modeling may be needed to prove that you have a robust design. Is this device on a sparse board or is it crowded with other heat generating devices? If the air space and/or air flow is restricted, a heat sink may be needed.
Tom
