Hi Simon
2nd, in my understanding, our conclusion at Renesas-ML is that we don't need to think about basic/extend DMAC register. Because extend area is 100% covering basic area. In other words, it is compatible. Driver side don't need to think about it.
I am a little confused, because latest comment received from simon, suggests to let driver to decide which register set to use.
for me, I think it's not necessary, if extended register set is available, driver shall always use it.
I can agree to have both basic/extend register if driver need to switch its behavior. But this case, there is nothing to do on driver side. In other words, SoC always need to use extend register if it has. I don't know why datasheet is indicating both area. Maybe it is because for Gen3 all-in ? I'm not sure.
Anyway, Simon, can you agree about it ? Having both basic/extend register is just noise for driver.
Best regards --- Kuninori Morimoto