The fallback was introduced in commit 80c33624e472 ("io-mapping: Fixup for different names of writecombine") to fix the build on microblaze.
5 years later, it seems all archs now provide a pgprot_writecombine(), so just remove the other possible fallbacks. For microblaze, pgprot_writecombine() is available since commit 97ccedd793ac ("microblaze: Provide pgprot_device/writecombine macros for nommu").
This is build-tested on microblaze with the following hack to always build mm/io-mapping.o and without diying on a x86-only macro (_PAGE_CACHE_MASK)
Cc: Chris Wilson chris@chris-wilson.co.uk Cc: Daniel Vetter daniel.vetter@ffwll.ch Cc: Joonas Lahtinen joonas.lahtinen@linux.intel.com Cc: linux-mm@kvack.org Cc: Peter Zijlstra peterz@infradead.org Cc: Andrew Morton akpm@linux-foundation.org Signed-off-by: Lucas De Marchi lucas.demarchi@intel.com --- include/linux/io-mapping.h | 6 ------ 1 file changed, 6 deletions(-)
diff --git a/include/linux/io-mapping.h b/include/linux/io-mapping.h index e9743cfd8585..66a774d2710e 100644 --- a/include/linux/io-mapping.h +++ b/include/linux/io-mapping.h @@ -132,13 +132,7 @@ io_mapping_init_wc(struct io_mapping *iomap,
iomap->base = base; iomap->size = size; -#if defined(pgprot_noncached_wc) /* archs can't agree on a name ... */ - iomap->prot = pgprot_noncached_wc(PAGE_KERNEL); -#elif defined(pgprot_writecombine) iomap->prot = pgprot_writecombine(PAGE_KERNEL); -#else - iomap->prot = pgprot_noncached(PAGE_KERNEL); -#endif
return iomap; }