NXP are open sourcing a lot of the support stack for the LA9310 to go along with this product release, but I'm afraid they consider the VSPA DSP to be highly proprietary, yes.
Example: https://github.com/nxp-qoriq?q=la93
Example: https://github.com/nxp-qoriq?q=la93
NXP doesn't share many details on the LA9310. Could just be too early, but it smells like a "you must convince a sales rep you're going to be a qualified customer and sign a stack of NDAs before you dare ask for a datasheet or instruction set manual" situation, which is unfortunate.