Overclocking a video card under Linux: only firmware?

Question

AMD

There is a Sapphire RX470 Nitro +, so that it normally chases under the bus, you need to change the BIOS (in order to remove certain restrictions in order to overclock the memory normally), after which the card is driven by wattman through the crimson, but here's how to make overclocking plow on Linux? MB somehow you can set higher frequencies in the BIOS, which then sew up?