Looking for a PCIE 3.0 to MIPI CSI 2 bridge IC.

We have 4 cameras we like to connect to a central SOC, while this chip does have 2 MIPI CSI 2 ports, they're now both taken by the first 2 cameras. But these don't support virtual csi (splitting the 4 data lanes to 2 channels) 

We do still have a PCIe 3 port available. So I wondered if there are any converter/bridge chips that we can use to give us ether 2 *  2 lane channels.

Or a single 4 lane we can split?

Are there any Ti parts that we can use?

Thanks in advanced.

Best regards

Simon