(A) fixed-point 3D graphics library with energy-efficient cache architecture for mobile multimedia systems

Abstract

A 3D computer graphics (3DCG) library is implemented for mobile multimedia systems. The developed library is based on fixed-point arithmetic for low energy consumption. To achieve high performance, the library is optimized at both the assembly and the algorithm levels on 3 different Advanced RISC Machines (ARM) processors. In order to enhance energy efficiency as well as performance, a series of simulations have been performed on application program with various cache configurations. In the CPU cache analysis, it is found that a 2-way set associative cache consumes low energy with negligible performance degradation. In this cache system, I can accomplish 16% energy saving compared to a 4-way conventional cache architecture, with only a 0.7% performance degradation on an average, running mobile 3D graphics application. For the texture cache analysis, I present a new texture maps representation, Recursive-Sub-Block (RSB). With RSB using bilinear filtering as a texture filtering and sampling method, I can accomplish 36% miss rate reduction, 26.7% execution time saving and 33.6% energy saving on an average compared with conventional texture maps representations in 1KB cache system. I will also perform the image quality comparison between four filtering methods in mobile applications and I can accomplish high quality of texture mapping with acceptable energy consumption with bilinear MIPMAP. Finally, series of simulations are performed to find the energy-efficient cache configurations and it is found that a 4K byte direct mapped texture cache shows good energy-efficiency.