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: NToshi Kani <toshi.kani@hp.com>
Signed-off-by: NBorislav 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.deSigned-off-by: NIngo Molnar <mingo@kernel.org>

ARC's asm/io.h includes the asm-generic/io.h which already defines the
PCI_IOBASE variable in exactly the same way, so it can be dropped from
the architecture specific header.
Signed-off-by: NThierry Reding <treding@nvidia.com>

Some drivers require these, and ARC didn't had them yet.
Signed-off-by: NMischa Jonker <mjonker@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Implement ioremap_prot() to allow mapping IO memory with variable
protection
via TLB.

Implementing this allows the /dev/mem driver to use its generic access()
VMA callback, which in turn allows ptrace to examine data in memory
mapped regions mapped via /dev/mem, such as Arc DCCM.

The end result is that it is possible to examine values of variables
placed into DCCM in user space programs via GDB.

CC: Alexey Brodkin <Alexey.Brodkin@synopsys.com>
CC: Noam Camus <noamc@ezchip.com>
Acked-by: NVineet Gupta <vgupta@synopsys.com>
Signed-off-by: NGilad Ben-Yossef <gilad@benyossef.com>
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>

Signed-off-by: NVineet Gupta <vgupta@synopsys.com>