Re: [PATCH] Axi-usb: Add support for 64-bit addressing.

[Arnd Bergmann]

On Monday 18 April 2016 09:29:09 Rob Herring wrote:
> 
> Right, you don't need to know the exact bus width for determining the 
> register/descriptor set is 32 or 64 bit addesses. I'm fine with a 
> property for that, but if limiting the actual connected address bits is 
> needed, then dma-ranges should be used.

The other way round: dma-ranges is needed to allow 64-bit addressing,
the default is to only allow 32-bit addressing (and arm64 has a known
bug here, it just allows it anyway when it shouldn't).

	Arnd