SDP_LUT feature support for nvdla_small

[nainag]

Hi,

I am trying to understand the SDP core in nvdla_small. According to the documentation, Activation functions Sigmoid and Tanh are implemented using LUT. But, as per nvdla_small configuration, NVDLA_SDP_LUT_ENABLE is NO.

I would really appreciate if you can clarify my doubts:

1. What does it mean by NVDLA_SDP_LUT_ENABLE being NO? Does it mean LUT feature is not supported for nvdla_small or it is just not enabled?
2. If it is not supported, then how are the activation functions Sigmoid and Tanh implemented for nvdla_small?
3. Or if it is just disabled, then how can I enable it? Or is it a software feature and gets enabled dynamically?

Thanks in advance.