This patch will truncate and/or ignore memory banks if their kernel
direct mappings would (partially) overlap with the vmalloc area or
the mappings between the vmalloc area and the address space top, to
prevent crashing during early boot if there happens to be more RAM
installed than we are expecting.

Since the start of the vmalloc area is not at a fixed address (but
the vmalloc end address is, via the per-platform VMALLOC_END define),
a default area of 128M is reserved for vmalloc mappings, which can
be shrunk or enlarged by passing an appropriate vmalloc= command line
option as it is done on x86.

On a board with a 3:1 user:kernel split, VMALLOC_END at 0xfe000000,
two 512M RAM banks and vmalloc=128M (the default), this patch gives:

	Truncating RAM at 20000000-3fffffff to -35ffffff (vmalloc region overlap).
	Memory: 512MB 352MB = 864MB total

On a board with a 3:1 user:kernel split, VMALLOC_END at 0xfe800000,
two 256M RAM banks and vmalloc=768M, this patch gives:

	Truncating RAM at 00000000-0fffffff to -0e7fffff (vmalloc region overlap).
	Ignoring RAM at 10000000-1fffffff (vmalloc region overlap).
Signed-off-by: NLennert Buytenhek <buytenh@marvell.com>
Tested-by: NRiku Voipio <riku.voipio@iki.fi>

ext4 uses ZERO_PAGE(0) to zero out blocks.  We need to export
different symbols in different arches for the usage of ZERO_PAGE
in modules.
Signed-off-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

This patchset adds a flags variable to reserve_bootmem() and uses the
BOOTMEM_EXCLUSIVE flag in crashkernel reservation code to detect collisions
between crashkernel area and already used memory.

This patch:

Change the reserve_bootmem() function to accept a new flag BOOTMEM_EXCLUSIVE.
If that flag is set, the function returns with -EBUSY if the memory already
has been reserved in the past.  This is to avoid conflicts.

Because that code runs before SMP initialisation, there's no race condition
inside reserve_bootmem_core().

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix powerpc build]
Signed-off-by: NBernhard Walle <bwalle@suse.de>
Cc: <linux-arch@vger.kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently, Linux doesn't generate correct page tables for ARMv6 and
later cores if the cache policy is different from the default one (it
may lead to strongly ordered or shared device mappings). This patch
disallows cache policies other than writeback and the
CPU_[ID]CACHE_DISABLE options only affect the CP15 system control
register rather than the page tables.
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

AT91SAM9260 stopped booting with the recent changes to MM
initialisation - it was asking for a non-aligned virtual address
which caused loops to be non-terminal.  Fix this by rounding
virtual addresses down, but remember to include the offset in
the length, and round the length up to the following page.

This means that asking for a mapping of 4K starting at 2K into
a page maps two pages as one would expect.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Spelling fixes in arch/arm/.
Signed-off-by: NSimon Arlott <simon@fire.lp0.eu>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Add cached device type for ioremap_cached().  Group all device memory
types together, and ensure that they all have a "MT_DEVICE" prefix.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Change the memory types table to define the L1 descriptor bit 4 to
be in terms of the ARMv6 definition - execute never.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Add prot_pte_ext to the mem_types table to allow the extended pte
attributes to be passed to set_pte_ext(), thereby permitting us to
specify memory type information for the hardware PTE entries.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

We really want to be using the memory type table in ioremap, so we
only have to do the CPU type fixups in one place.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Rather than our three separate loops to setup mappings (by page
mappings up to a section boundary, then section mappings, and the
remainder by page mappings) convert this to a more conventional
Linux style of a loop over each page table level.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Catalin Marinas at ARM Ltd says:
> The CPU architects in ARM intended supersections only as a way to map
> addresses >= 4GB. Supersections are not mandated by the architecture
> and there is no easy way to detect their hardware support at run-time
> (other than checking for a specific core). From the analysis done in
> ARM, there wasn't a clear performance gain by using supersections
> rather than sections (no significant improvement in the TLB misses).

Therefore, we should avoid using supersections unless there's a real
need (iow, we're mapping addresses >= 4GB).

This means that we can simplify create_mapping() a bit since we will
only use supersection mappings for addresses >= 4GB, which means that
the physical, virtual and length must be multiples of the supersection
mapping size.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

There's now no need to carry around each protection separately.
Instead, pass around the pointer to the entry in the mem_types
array which we're interested in.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Rather than combining the domain for a particular memory type with
the protection information each time we want to use it, do so when
we fix up the mem_type array at initialisation time.

Rename struct mem_types to be mem_type - each structure is one
memory type description, not several.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The PAGE_* user page protection macros don't take into account the
configured memory policy and other architecture specific bits like
the global/ASID and shared mapping bits. Instead of constants let
these depend on a variable fixed up at init just like PAGE_KERNEL.
Signed-off-by: NImre Deak <imre.deak@solidboot.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Move adjust_cr() into arch/arm/mm/mmu.c, and move irqflags.h to
a more appropriate place in the header file.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

L_PTE_ASID is not really required to be stored in every PTE, since we
can identify it via the address passed to set_pte_at().  So, create
set_pte_ext() which takes the address of the PTE to set, the Linux
PTE value, and the additional CPU PTE bits which aren't encoded in
the Linux PTE value.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The RX3715 is similar to the H1940 in the way
that suspend to RAM works, so we can use most
of the extant support for the H1940 with only
a few modifictions
Signed-off-by: NBen Dooks <ben-linux@fluff.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Add support to suspend and resume, using the
H1940's bootloader
Signed-off-by: NBen Dooks <ben-linux@fluff.org>
Signed-off-by: NArnaud Patard <arnaud.patard@rtp-net.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Merge L_PTE_COHERENT with L_PTE_SHARED and free up a L_PTE_* bit.
Signed-off-by: NLennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

XIP kernels need to know the start/end of text, but we were
missing the declaration of _etext in mmu.c.  Add it.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

If we're going to have mmu.c for code which is specific to the MMU
machines, we might as well move the other MMU initialisation
specific code from mm-armv.c into this new file.  This also allows
us to make some functions static.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Move the MMU specific code from init.c into mmu.c, and add nommu
fixups to nommu.c
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Rename mmu.c to context.c - it's the ARMv6 ASID context handling
code rather than generic "mmu" handling code.
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!