Setting up SQM on Main Router

I have an openwrt router connected to my Modem which is in bridge mode so my openwrt router is my main router. On the router I have a ethernet cable connected to one of the lans on the router which connects to my switch that connects all the network jacks around the house to the router! In my room I have my ps4 plugged into one of the network jacks. Alright that’s really just some background info I thought was relevant. So on the openwrt router I have Sqm setup on the wan interface//queue discipline is cake and piece of cake// and link layer adaptation is ethernet overhead and packet is 18 because my modem is cable. I’m setting up SQM to lower the latency on my PS4 for my games and I was wondering is this the right setup or do I need to put the sqm interface to my lan?