I can't say much because NDA, but it's not the most difficult protocol to reverse engineer.
Also, if we decide to make our own RX IP for it, there's a good chance I can open source it. Will have to have a lawyer look over the licensing/NDA terms to make sure we're not messing anything up in that case.
Its (presumed) competitor, MIPI-CSI is not open source either.
SLVS-EC looks easier to interface with an FPGA at least, presumably the voltage levels are closer to standard, unlike MIPI D-PHY's exotic dual level switching that either requires an external IC, a passive resistor network of borderline compliance, or an FPGA (e.g. Lattice CrossLink) with the correct special inputs.
SLVS-EC has some very minor issues when interfacing (DC offset compliance) which requires a hack in detecting when the link is up. And yeah, MIPI D-PHY is a royal pain unless you have native support (Xilinx, Lattice, Intel Agilex 5). C-PHY even more so.
