Embedded Software for SoC - Grupo de Mecatrônica EESC/USP

186 Chapter 14
evaluation of HW architecture candidates. Thus, in this case, automatic HAL
design is needed to reduce the HAL design efforts. In terms of automatic
design of device drivers, there have been presented some work [6]. However,
general solutions to automatically generate the entire HAL need to be
developed. The general solutions need also to support both application-specific
and automatic design of HAL.
6. CONCLUSION
In this paper, we presented HAL definition, examples of HAL function, the
role of HAL in SoC design, and related issues. HAL gives an abstraction of
HW architecture to upper layer SW. In SoC design, the usage of HAL enables
SW reuse and concurrent HW and SW design. The SW code designed using
a HAL API can be reused, without code change, on different HW architectures
that support the same HAL API. The HAL API works also as a contract
between SW and HW designers to enable them to work concurrently without
bothering themselves with the implementation details of the other parts (HW
or SW).
As in the case of HW interface standards, the HAL API needs also a
standard. However, contrary to the case of HW interface standards, the
standard of HAL API needs to support new HW architectures in applicationspecific
SoC design as well as the common functionality of HAL. Thus, the
standard needs to have a common HAL API(s) and a guideline to expand the
generic one to support new HW architectures. To facilitate the early validation
of reused SW, we need also the simulation model of HAL. To reduce the
overhead of implementing HAL (i.e. design cycle) and that of HAL implementation
itself (i.e. code size, execution time overhead), we need methods
of automatic and application-specific HAL design.
REFERENCES
1.
2.
3.
4.
5.
6.
7.
Virtual Socket Interface Alliance, http://www.vsi.org/
Open Core Protocol, http:// http://www.ocpip.org/home
Windows CE, http://www.microsoft.com/windows/embedded/
D. Probert, et al. “SPACE: A New Approach to Operating System Abstraction.” Proceedings
of International Workshop on Object Orientation in Operating Systems, pp. 133–137, October
1991.
S. M. Tan, D. K. Raila, and R. H. Campbell. “An Object-Oriented Nano-Kernel for Operating
System Hardware Support.” In Fourth International Workshop on Object-Orientation in
Operating Systems, Lund, Sweden, August 1995.
S. Wang, S. Malik, and R. A. Bergamaschi, “Modeling and Integration of Peripheral Devices
in Embedded Systems.” Proceedings of DATE (Design, Automation, and Test in Europe),
March 2003.
S. Yoo, A. Bouchhima, I. Bacivarov, and A. A. Jerraya. “Building Fast and Accurate SW
Simulation Models based on SoC Hardware Abstraction Layer and Simulation Environment
Abstraction Layer.” Proceedings of DATE, March 2003.