In anticipation of the prevalence of reconfigurability in future integrated circuits, this paper presents a practical hardware-software codesign methodology for customizing domain-specific reconfigurable platforms to meet the application constraints in a timely manner. The proposed framework exploits existing MISRA C compliant software in order to meet the increasing time-to-market pressures while enabling product differentiation through modest custom hardware accelerator implementation in the reconfigurable logic. A key step in the design methodology for reducing the effort of hardware customization lies in platform-aware hardware-software partitioning, which takes into consideration the communication overhead between the various computing elements. In order to demonstrate the viability of the proposed methodology, we present a case study on extended Kalman filter based motor control for automotive applications. We show that the proposed methodology can effectively identify a cost effective candidate for hardware acceleration embracing domain-specific characteristics and existing standard-compliant software.