FSL 64-bit DMA window question

[Benjamin Herrenschmidt]

Hi Folks !

Is there any specific reason why you chose 1T (40 bit) as the location
of the 64-bit DMA window ?

It happens that most current radeon adapters cannot DMA there, they have
a 40-bit DMA limit. I seem to be getting things to work fine using a
39-bit window, but I suppose that might collide with something else ?

Can you guys consider changing the default ?

Cheers,
Ben.