Where is the IDCODE in the E31-rtl?

I want to find the IDCODE in the RTL of E31 code,where is the IDCODE defined?

The IDCODE is set within the design to 0x20000XXX, where the 11-bit MFR ID can be specified at the top level signal, io_jtag_mfr_id. In other words, VERSION is 0x2, PARTNUM is 0x0, and MFR is set outside the E-31 coreplex.