STP Select the upstream router to be the root

[xZamalek]

Hello,

We have a Cisco switch connected to the CE , the Switch connected via trunk link to the router carries 4 vlans , the switch select the interface going to the router to be the root port , my question is , is this normal ? when the Provider checked the CE there is no STP configured on the router , how the Router send BPDU then to the downstream switch ?

[MHM Cisco World]

if the PE is run l2VPN then it can bypass BPDU from other site to your site. 
make double check with them about the config of bridge of L2VPN in PE

[xZamalek]

Thank you , will check on that the ISP.