the best thing about ghidra is that no matter which version you're using, setting equates sometimes just doesn't work, but if you google it, you only find several bug reports which basically say "equates don't work" and then it's "closed, fixed in X.Y.Z" and that's a version you're upgraded way past
port_out(0x3c4,0xf02);
I SO WANT TO EQUATE 0x3C4 TO THE VGA SEQUENCER INDEX REGISTER BUT I CAN'T