Gray symbols in diagram. What do they mean?

[Tobe]

I spend quite some time trying to figure out, what the gray symbols/areas mean. Still i dont know. Any one knows this?

[waclawek.jan]

Voltage domains different from the 1.2V domain (generated by internal voltage regulator from VDD) at which most of the chip runs. You have the voltage marked next to those areas (mostly).

JW