Ensure that the ISA/PCI IO space accessors are properly ordered on
ARMv6+ architectures.  These should always be ordered with respect to
all other accesses.

This also fixes __iormb() and __iowmb() not being visible to ioread/
iowrite if a platform defines its own MMIO accessors.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

We don't need to repeat the same definitions of the ioremap*(),
once in terms of __arch_ioremap() and again in terms of __arm_ioremap().
Instead, if the platform hasn't provided an __arch_ioremap, define
this to be __arm_ioremap, and only define the ioremap*() set using
__arch_ioremap.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Defining iounmap() with arguments prevents it from being used as a
function pointer, causing platforms to work around this.  Instead,
define it to be a simple macro.

Do the same for __arch_io(re|un)map too.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

There are very few legitimate use cases, if any, for directly accessing
system RAM through /dev/mem.  So let's mimic what they do on x86 and
forbid it when CONFIG_STRICT_DEVMEM is turned on.
Signed-off-by: NNicolas Pitre <nicolas.pitre@linaro.org>

The ioread/iowrite accessors also need barriers as they're used in
place of readl/writel et.al. in portable drivers.  Create __iormb()
and __iowmb() which are conditionally defined to be barriers dependent
on ARM_DMA_MEM_BUFFERABLE, and always use these macros in the accessors.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

When the coherent DMA buffers are mapped as Normal Non-cacheable
(ARM_DMA_MEM_BUFFERABLE enabled), buffer accesses are no longer ordered
with Device memory accesses causing failures in device drivers that do
not use the mandatory memory barriers before starting a DMA transfer.
LKML discussions led to the conclusion that such barriers have to be
added to the I/O accessors:

http://thread.gmane.org/gmane.linux.kernel/683509/focus=686153
http://thread.gmane.org/gmane.linux.ide/46414
http://thread.gmane.org/gmane.linux.kernel.cross-arch/5250

This patch introduces a wmb() barrier to the write*() I/O accessors to
handle the situations where Normal Non-cacheable writes are still in the
processor (or L2 cache controller) write buffer before a DMA transfer
command is issued. For the read*() accessors, a rmb() is introduced
after the I/O to avoid speculative loads where the driver polls for a
DMA transfer ready bit.
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This patch introduces readl*_relaxed()/write*_relaxed() as the main I/O
accessors (when __mem_pci is defined). The standard read*()/write*()
macros are now based on the relaxed accessors.

This patch is in preparation for a subsequent patch which adds barriers
to the I/O accessors.
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This allows the procfs vmallocinfo file to show who created the ioremap
regions.  Note: __builtin_return_address(0) doesn't do what's expected
if its used in an inline function, so we leave __arm_ioremap callers
in such places alone.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

As Al did for Versatile in 2ad4f86b,
add a typesafe __io implementation for platforms to use.  Convert
platforms to use this new simple typesafe implementation.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

As of the previous commit, MT_DEVICE_IXP2000 encodes to the same
PTE bit encoding as MT_DEVICE, so it's now redundant.  Convert
MT_DEVICE_IXP2000 to use MT_DEVICE instead, and remove its aliases.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This patch provides an ARM implementation of ioremap_wc().

We use different page table attributes depending on which CPU we
are running on:

- Non-XScale ARMv5 and earlier systems: The ARMv5 ARM documents four
  possible mapping types (CB=00/01/10/11).  We can't use any of the
  cached memory types (CB=10/11), since that breaks coherency with
  peripheral devices.  Both CB=00 and CB=01 are suitable for _wc, and
  CB=01 (Uncached/Buffered) allows the hardware more freedom than
  CB=00, so we'll use that.

  (The ARMv5 ARM seems to suggest that CB=01 is allowed to delay stores
  but isn't allowed to merge them, but there is no other mapping type
  we can use that allows the hardware to delay and merge stores, so
  we'll go with CB=01.)

- XScale v1/v2 (ARMv5): same as the ARMv5 case above, with the slight
  difference that on these platforms, CB=01 actually _does_ allow
  merging stores.  (If you want noncoalescing bufferable behavior
  on Xscale v1/v2, you need to use XCB=101.)

- Xscale v3 (ARMv5) and ARMv6+: on these systems, we use TEXCB=00100
  mappings (Inner/Outer Uncacheable in xsc3 parlance, Uncached Normal
  in ARMv6 parlance).

  The ARMv6 ARM explicitly says that any accesses to Normal memory can
  be merged, which makes Normal memory more suitable for _wc mappings
  than Device or Strongly Ordered memory, as the latter two mapping
  types are guaranteed to maintain transaction number, size and order.
  We use the Uncached variety of Normal mappings for the same reason
  that we can't use C=1 mappings on ARMv5.

  The xsc3 Architecture Specification documents TEXCB=00100 as being
  Uncacheable and allowing coalescing of writes, which is also just
  what we need.
Signed-off-by: NLennert Buytenhek <buytenh@marvell.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This just leaves include/asm-arm/plat-* to deal with.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Move platform independent header files to arch/arm/include/asm, leaving
those in asm/arch* and asm/plat* alone.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We don't need valid_phys_addr_range() or valid_mmap_phys_addr_range()
for the !CONFIG_MMU case.
Signed-off-by: NGreg Ungerer <gerg@uclinux.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

__ioremap() took a set of page table flags (specifically the cacheable
and bufferable bits) to control the mapping type.  However, with
the advent of ARMv6, this is far too limited.

Replace the page table flags with a memory type index, so that the
desired attributes can be selected from the mem_type table.

Finally, to prevent silent miscompilation due to the differing
arguments, rename the __ioremap() and __ioremap_pfn() functions.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

On all targets that sucker boils down to memcpy_fromio(sbk->data, from, len).
The function name is highly misguiding (it _never_ does any checksums), the
last argument is just a noise and simply expanding the call to memcpy_fromio()
gives shorter and more readable source.  For a lot of reasons it has almost
no remaining users, so it's better to just outright kill it.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Since the last definitions of this macros have been removed, we
can remove the warnings in asm/io.h.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

There's nothing arch-specific about check_signature(), so move it to
<linux/io.h>.  Use a cross between the Alpha and i386 implementations as
the generic one.
Signed-off-by: NMatthew Wilcox <willy@parisc-linux.org>
Acked-by: NAlan Cox <alan@redhat.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Prevent userland from mapping in physical address regions >= 4G by
checking for that in valid_mmap_phys_addr_range().

Unfortunately, we cannot override valid_mmap_phys_addr_range() without
also overriding valid_phys_addr_range(), so copy drivers/char/mem.c's
version of valid_phys_addr_range() over to arch/arm/mm/mmap.c as well.
Signed-off-by: NLennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

unused isa_...() helpers removed.

Adrian Bunk:
The asm-sh part was rediffed due to unrelated changes.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Patch from Deepak Saxena

In working on adding 36-bit addressed supersection support to ioremap(),
I came to the conclusion that it would be far simpler to do so by just
splitting __ioremap() into a main external interface and adding an
__ioremap_pfn() function that takes a pfn + offset into the page that
__ioremap() can call. This way existing callers of __ioremap() won't have
to change their code and 36-bit systems will just call __ioremap_pfn()
and we will not have to deal with unsigned long long variables.

Note that __ioremap_pfn() should _NOT_ be called directly by drivers
but is reserved for use by arch_ioremap() implementations that map
32-bit resource regions into the real 36-bit address and then call
this new function.
Signed-off-by: NDeepak Saxena <dsaxena@plexity.net>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Patch from Deepak Saxena

Mark the ioremap'd cookie/pointer in said functions as const since
we should not be actualy touching the data. This fixes a slew of
compile warnings on IXP4xx as our reads[bwl] already mark this
parameter as const.
Signed-off-by: NDeepak Saxena <dsaxena@plexity.net>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The "align" argument in ARMs __ioremap is unused and provides a
misleading expectation that it might do something.  It doesn't.
Remove it.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Including asm/hardware.h into asm/io.h can cause #define clashes
between platform specific definitions and driver local definitions.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Add 'volatile' to the __iomem pointers for these functions as
per x86.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Patch from Lennert Buytenhek

This patch conditionalises the io{read,write}{8,16,32} defines and the
prototypes for ioport_map/ioport_unmap in asm-arm/io.h on ioread8 not
already having been defined.  This is done so that platforms can provide
their own implementation of the iomap API, ixp2000 for example needs
this.
Signed-off-by: NLennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: Deepak Saxena
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Patch from Olav Kongas

On ARM, the outX() and writeX() families of macros take the
result of cpu_to_leYY(), which is of restricted type __leYY,
and feed it to __raw_writeX(), which expect an argument of
unrestricted type. This results in 'sparse -Wbitwise'
warnings about incorrect types in assignments. Analogous
type mismatch warnings are issued for inX() and readX()
counterparts. The below patch resolves these warnings by
adding forced typecasts.

Signed-off-by: Olav Kongas
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!