eNodeB will not provide any PDCP configuration for SRB 1 and 2.
In general as per the RRC specification, while establishing DRB's eNodeB will provide the below configurations:-
rlc-mode, ROHC profile, integrity protection flag, PDU discard timer and sequence number bit length etc..
But for SRB's by default PDCP has the below configuration as per the PDCP specification:-
rlc-mode(AM), Integrity Protection enabled, and fixed 5 bit sequence number bit length.