KIO region location is different for noMMU cores. Provide different
default physical address and make KIO virtual address equal to physical.

Move xtensa_get_kio_paddr function close to XCHAL_KIO_PADDR definition
and define it not only for MMUv3, but for all MMU options except MMUv2.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Existing users of ioremap_cache() are mapping memory that is known in
advance to not have i/o side effects.  These users are forced to cast
away the __iomem annotation, or otherwise neglect to fix the sparse
errors thrown when dereferencing pointers to this memory.  Provide
memremap() as a non __iomem annotated ioremap_*() in the case when
ioremap is otherwise a pointer to cacheable memory. Empirically,
ioremap_<cacheable-type>() call sites are seeking memory-like semantics
(e.g.  speculative reads, and prefetching permitted).

memremap() is a break from the ioremap implementation pattern of adding
a new memremap_<type>() for each mapping type and having silent
compatibility fall backs.  Instead, the implementation defines flags
that are passed to the central memremap() and if a mapping type is not
supported by an arch memremap returns NULL.

We introduce a memremap prototype as a trivial wrapper of
ioremap_cache() and ioremap_wt().  Later, once all ioremap_cache() and
ioremap_wt() usage has been removed from drivers we teach archs to
implement arch_memremap() with the ability to strictly enforce the
mapping type.

Cc: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

Add ioremap_wt() to all arch-specific asm/io.h headers which
define ioremap_wc() locally. These headers do not include
<asm-generic/iomap.h>. Some of them include <asm-generic/io.h>,
but ioremap_wt() is defined for consistency since they define
all ioremap_xxx locally.

In all architectures without Write-Through support, ioremap_wt()
is defined indentical to ioremap_nocache().

frv and m68k already have ioremap_writethrough(). On those we
add ioremap_wt() indetical to ioremap_writethrough() and defines
ARCH_HAS_IOREMAP_WT in both architectures.

The ioremap_wt() interface is exported to drivers.

Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Elliott@hp.com
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: arnd@arndb.de
Cc: hch@lst.de
Cc: hmh@hmh.eng.br
Cc: jgross@suse.com
Cc: konrad.wilk@oracle.com
Cc: linux-mm <linux-mm@kvack.org>
Cc: linux-nvdimm@lists.01.org
Cc: stefan.bader@canonical.com
Cc: yigal@plexistor.com
Link: http://lkml.kernel.org/r/1433436928-31903-9-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>

These are now defined by asm-generic/io.h, so we don't need the private
definitions anymore.

Cc: Chris Zankel <chris@zankel.net>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

The warning only shows up when building MMUv3 configuration with OF
support disabled.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Use the simple-bus node to discover the io area, and remap the cached and
bypass io ranges. The parent-bus-address value of the first triplet in the
"ranges" property is used. This value is rounded down to the nearest 256MB
boundary. The length of the io area is fixed at 256MB; the "ranges" property
length value is ignored.

Other limitations: (1) only the first simple-bus node is considered, and (2)
only the first triplet of the "ranges" property is considered.

See ePAPR 1.1 §6.5 for the simple-bus node description, and §2.3.8 for the
"ranges" property description.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Define IO addresses in a single place, to make it easier to change for
non-standard memory maps.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

Define virt_to_bus and bus_to_virt as virt_to_phys, and phys_to_virt,
       respectively.

Signed-off-by: Chris Zankel <chris@zankel.net>

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>

- fix ioremap_nocache to actually return non-cacheable address
- add explicit ioremap_cache
- fix KIO aperture checking arithmetic

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>