Design Idea of the 3A Architecture

The basic design idea is that the ISP firmware initializes and destroys each algorithm unit, provides the statistics of the previous frame, and configures registers based on the return value during running. Other parts are developed by users. Therefore, after you replace the 3A algorithm, the MPIs of the current AE/AWB, the AE/AWB-related content in cmos.c, the AE weight configuration, and AWB white point search configuration cannot be reused. Theoretically, these configurations are set by the 3A algorithm instead of being obtained from the ISP firmware which has only simple initialization values.

The 3A algorithm does not explicitly configure or read the ISP registers. Instead, you only need to write the ISP register values to be configured to hi_isp_ae_result and hi_isp_awb_result, and read the ISP registers from hi_isp_ae_info and hi_isp_awb_info.