pmb_bolt_mapping() is undefined on 29-bit builds, so provide a stub.
This fixes up the NUMA build on platforms lacking PMB support.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

This implements a fairly significant overhaul of the dynamic PMB mapping
code. The primary change here is that the PMB gets its own VMA that
follows the uncached mapping and we attempt to be a bit more intelligent
with dynamic sizing, multi-entry mapping, and so forth.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

This implements a bit of rework for the PMB code, which permits us to
kill off the legacy PMB mode completely. Rather than trusting the boot
loader to do the right thing, we do a quick verification of the PMB
contents to determine whether to have the kernel setup the initial
mappings or whether it needs to mangle them later on instead.

If we're booting from legacy mappings, the kernel will now take control
of them and make them match the kernel's initial mapping configuration.
This is accomplished by breaking the initialization phase out in to
multiple steps: synchronization, merging, and resizing. With the recent
rework, the synchronization code establishes page links for compound
mappings already, so we build on top of this for promoting mappings and
reclaiming unused slots.

At the same time, the changes introduced for the uncached helpers also
permit us to dynamically resize the uncached mapping without any
particular headaches. The smallest page size is more than sufficient for
mapping all of kernel text, and as we're careful not to jump to any far
off locations in the setup code the mapping can safely be resized
regardless of whether we are executing from it or not.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

This implements some locking for the PMB code. A high level rwlock is
added for dealing with rw accesses on the entry map while a per-entry
data structure spinlock is added to deal with the PMB entry changing out
from underneath us.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

This plugs in entry sizing support for existing mappings and then builds
on top of that for linking together entries that are mapping contiguous
areas. This will ultimately permit us to coalesce mappings and promote
head pages while reclaiming PMB slots for dynamic remapping.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

Some overdue cleanup of the PMB code, killing off unused functionality
and duplication sprinkled about the tree.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

Both the store queue API and the PMB remapping take unsigned long for
their pgprot flags, which cuts off the extended protection bits. In the
case of the PMB this isn't really a problem since the cache attribute
bits that we care about are all in the lower 32-bits, but we do it just
to be safe. The store queue remapping on the other hand depends on the
extended prot bits for enabling userspace access to the mappings.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

This merges the code for iterating over the legacy PMB mappings and the
code for synchronizing software state with the hardware mappings. There's
really no reason to do the same iteration twice, and this also buys us
the legacy entry logging facility for the dynamic PMB case.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

Presently __in_29bit_mode() is only defined for the PMB case, but
it's also easily derived from the CONFIG_29BIT and CONFIG_32BIT &&
CONFIG_PMB=n cases.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

The last commit introduced the following breakage

arch/sh/include/asm/mmu.h: In function 'pmb_remap':
arch/sh/include/asm/mmu.h:79: error: expected ';' before '}' token

and...

arch/sh/include/asm/mmu.h:78: error: 'EINVAL' undeclared (first use in this function)
arch/sh/include/asm/mmu.h:78: error: (Each undeclared identifier is reported only once
arch/sh/include/asm/mmu.h:78: error: for each function it appears in.)
arch/sh/include/asm/mmu.h: In function 'pmb_init':
arch/sh/include/asm/mmu.h:87: error: 'ENODEV' undeclared (first use in this function)

Signed-off-by: Matt Fleming <matt@console-pimps.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>