ICE40 16bit 256 words ROM usage

[PPlinux]

Dear,

how can I use ICE40 internal RAM block memory as a 16 bit 256 word ROM memory ?

Is there someone who has written already (Intel/Motorola) HEX format to ICE40 block RAM/ROM required format conversion program ?

I suppose internal block RAM will be loaded with ROM data during FPGA configuration (from internal EEPROM) or programming via programming tool of the ICE40 ?

Greetings,

Patrick Pelgrims