Jerky screen update on my Embedded device running on cortex A9.

Hi All, I am running the a CSS content in html file with Qt demo browser 0.1 on my STB running on Cortex A9 processor with Qt 4.8.3. I am using directfb in the background for blitting. Though my dfb blits operations are pretty much compliant, the screen update looks jerky. In Qdirectfbpaintengine.cpp, for solid pattern a blit is done in directfb, and for TexturePattern pattern a batch blit is being done. The time difference between these two operations is around 80 milliseconds that comes around two frames. As the update happens in two consecutive frames we see a jerk in the update. Is there a way that webkit updates the complete content in one frame ? Please help. Regards, Sridhar