Configure DMA atributes?

[Gareth Davies]

On Mon, 12 Aug 2013 19:55:35 +0200, you wrote:
>
> From: drivers/net/ethernet/realtek/8139cp.c
>
[snip]
>
> If I comment the assignment to pci_using_dac, the compiler issues
> warnings, but it makes no visible difference to assign 1 or 0.
>
> If I had real hardware what could I brake by playing with this code?
>

Does the following help:
<URL:http://en.wikipedia.org/wiki/Conventional_PCI#Dual-cycle_address>

On real hardware, when using a PCI bus, setting the PCIDAC flag in  
8139cp.c is intended to signify that 64-bit addressing is being used.

-- 
Gareth Davies, Lotwillow Ltd