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If you configure a L3 switch with SVI, to perform the inter-VLAN routing on it, and then use a switch port as routed, to connect to your router, the router's port would just be configured "normally", i.e. without subinterfaces. You would route between the L3 switch and the router, normally using a p2p subnet.
BTW, when using a L3 switch and router, there are other possible combinations. For example, you might still have a trunk port on the L3 switch that connects to a router port with subinterfaces. Then the router's interfaces and the L3 switch would both have gateway addresses on all your subnets. If you made the SVI the default GW, it would redirect clients to the router for off VLAN traffic. Conversely, the router would send its traffic to the hosts, at L2, bypassing using the switch's L3. (In theory, having some traffic bypass the switch, at L3, would be just a tiny, tiny bit faster, but generally, this isn't worth doing, unless the router was connected to another L2 switch as is the L3 switch. In the latter, you could also configure HSRP between the L3 devices, and if the L3 switch failed, the router would route between VLANs.)
