Openwrt only allows one ipv6 routed prefix configured in the 6in4 tunnel. Therefore, I cannot configure both the routed /64 and /48 in the router. Is here anyone knows how to configure so that I don't need to enter the command on every boot?
I assume this is your routed /64 and not your tunnel /64?
If that's the case, you don't need your routed /64...you have 64k worth of /64's in your /48
Maybe you are right, it is impossible to use all the /64 prefixes in a /48 prefix.