Re: [PATCH v4 12/16] parisc: mm: Convert to GENERIC_IOREMAP

[Baoquan He]

On 02/16/23 at 01:50pm, Matthew Wilcox wrote:
> On Thu, Feb 16, 2023 at 08:34:15PM +0800, Baoquan He wrote:
> > Meanwhile, add macro ARCH_HAS_IOREMAP_WC since the added ioremap_wc()
> > will conflict with the one in include/asm-generic/iomap.h, then an
> > compiling error is seen:
> 

Thanks for reviewing.

> Huh?  ARCH_HAS_IOREMAP_WC comes up nowhere else in this patchset, and
> the current definition of ioremap_wc() is guarded by an ifndef ioremap_wc

Because another patch of powerpc has got ARCH_HAS_IOREMAP_WC in the
existed code.

> 
> > +#define ioremap_wc(addr, size)  \
> > +	ioremap_prot((addr), (size), _PAGE_IOREMAP)
> 
> This should be enough all by itself.

It's not if including asm-generic/iomap.h. The ARCH_HAS_IOREMAP_xx is to
avoid redefinition there.

include/asm-generic/iomap.h:
----
#ifndef ARCH_HAS_IOREMAP_WC
#define ioremap_wc ioremap
#endif

>