128qam return modulation with cisco

Hi

We are currently bonding several 64qam modulation /6.4Mhz wide returns and I think this is the max we can do

this link

https://en.wikipedia.org/wiki/DOCSIS

talks about

128-QAM with trellis coded modulation

in upstream

anyone knows if this is possible with cisco ubr ?

if yes what would be the hardware requirements ?

Thanks