[PATCH] nvme: prepare support for Apple NVMe controller

[Christoph Hellwig]

On Thu, Oct 29, 2015 at 09:10:56AM -0600, Jon Derrick wrote:
> > +#define readq lo_hi_readq
> > +#define writeq lo_hi_writeq
> > +
> 
> Good job figuring that one out. But this should be a quirk:
> a) It will sacrifice some io cycles on other devices
> b) It may get lost at some point in the name of performance
> 
> Christoph recently added a quirks mechanism where I think it would fit

We never access 64 bit registers in the fast path.  I'd be fine to
apply the patch from Stephan as-is as long as we document in detail why
we are doing this.  Stephan, can you respin the patch with a comment
and also with the PCI ID for the Apple controller added to the ID table?