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For inquiries about the Thunderbolt* controller you could refer to the thunderbolt* website and contact them directly, below you can find the link to their website:
Also, since you have an FPGA device, please go to Intel.com > select FPGA and Programmable Devices > then All FPGA & Programmable Devices > From the list you can see most of the products and below that additional options such as Documentation, How to Buy and the FPGA Product Selector.
You can also post your question on the Intel Community in the “FPGA Design Tools Forum”:
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