Re: [PATCH v7 5/7] io-64-nonatomic: add io{read|write}64[be]{_lo_hi|_hi_lo} macros

From: Andy Shevchenko
Date: Tue Aug 22 2017 - 13:40:14 EST


On Tue, Aug 22, 2017 at 8:02 PM, Logan Gunthorpe <logang@xxxxxxxxxxxx> wrote:
> This patch adds generic io{read|write}64[be]{_lo_hi|_hi_lo} macros if
> they are not already defined by the architecture. (As they are provided
> by the generic iomap library).
>
> The patch also points io{read|write}64[be] to the variant specified by the
> header name.
>
> This is because new drivers are encouraged to use ioreadXX, et al instead
> of readX[1], et al -- and mixing ioreadXX with readq is pretty ugly.
>
> [1] ldd3: section 9.4.2

ldd -> LDD

It's a pretty outdated book, though quite many chapters are actual for
these days.

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?

> cc: Christoph Hellwig <hch@xxxxxx>
> cc: Arnd Bergmann <arnd@xxxxxxxx>
> cc: Alan Cox <gnomes@xxxxxxxxxxxxxxxxxxx>
> cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

cc -> Cc ?

--
With Best Regards,
Andy Shevchenko