I think that either flaked corn or corn flakes could work really well for this. The process behind farinha de milho* is different from both (the maize is hulled, soaked, ground while wet, and dried over low fire), but as long as it’s something pre-cooked it should be fine. And as I mentioned in another comment, people make farofa even out of rolled oats.
*even in Portuguese alone the name is a bit messy, as it’s shared with the maize meal used for polenta. Most people specify the later as “fubá”, I’m used to specify the former as “farinha biju” (biju is the flakes).
I’ve done this once after seeing it in a Chinese recipe for chicken thighs, with Shaoxing wine. Apparently the alcohol does wonders to bring the flavour out of onions.