On Tue, Aug 22, 2017 at 8:55 PM, Logan Gunthorpe [off-list ref] wrote:

On 22/08/17 11:40 AM, Andy Shevchenko wrote:

quoted

Recomendation is kinda arguable. I doubt modern architectures make
difference between IO operations and MMIO.
Does, for example, PCI requires some special signal (message / wire)
handling when pio_*() accessors used vs. mmio_*() ones?

Sort of. There is a difference between the two in x86.

Yes, the difference is in signaling. The question is if it's still in
use. Looks like yes...

But really if it's
not a valid recommendation someone should just go through and deprecate one
of them or document better when one should be used over the other. In any
case it's still really ugly to mix the two types in the same driver.

Mixing is ugly, totally agree.

-- 
With Best Regards,
Andy Shevchenko