On Wed, Jul 1, 2015 at 8:59 AM, Christoph Hellwig <hch(a)lst.de> wrote:
On Wed, Jul 01, 2015 at 08:55:57AM +0200, Geert Uytterhoeven wrote:
> > I think doing this at runtime might be a better idea. E.g. a
> > ioremap_flags with the CACHED argument will return -EOPNOTSUP unless
> > actually implemented. On various architectures different CPUs or
> > boards will have different capabilities in this area.
> So it would be the responsibility of the caller to fall back from
> ioremap(..., CACHED) to ioremap(..., UNCACHED)?
> I.e. all drivers using it should be changed...
All of the zero users we currently have will need to be changed, yes.
Good. Less work to convert all of these ;-)
Note that I propose to leave ioremap(), aka ioremap_flags(..., 0) as
a default that always has to work, -EOPNOTSUP is only a valid return
value for non-default flaga.
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert(a)linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like
-- Linus Torvalds