Depends what you're trying to understand. If you're trying to reverse-engineer it then you will need to decompile it, which is outside my realm of experience. If you just want to see how the card is configured, then there are some tools available. For older AMD cards there is
Radeon BIOS Editor. For newer AMD cards there is
RED BIOS EDITOR (which I have not tried, so I don't know if it works). For nVidia cards... I don't know.