Most ARM machines don't need a special "DMA" memory zone, and
when configured out, the kernel becomes a bit smaller:

|   text    data     bss     dec     hex filename
|3826182  102384  111700 4040266  3da64a vmlinux
|3823593  101616  111700 4036909  3d992d vmlinux.nodmazone

This is because the system now has only one zone total which effect is
to optimize away many conditionals in page allocation paths.

So let's configure this zone only on machines that need split zones.
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

These instructions were placed in the code directly as opcodes because
early compilers didn't support them. Toolchains supporting ARMv7
understand these instructions and the patch puts the mnemonics back.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

There is no point converting memory bank addresses from physical to
virtual just to convert them back to physical addresses.  Furthermore
this isn't "right" for highmem even if in this case the end result is
the correct one.
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Enable Sparsemem support for LH7A40x SoCs, while still allowing the
existing discontig support for the time being.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

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

Tested on Assabet, and Assabet with Neponset's SDRAM at 3328M phys.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

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

... including some comments about the ordering required to bring
sparsemem up.  You have to repeatedly guess, test, reguess, try
again and again to work out what the right ordering is.  Many
hours later...
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Provide helpers for getting physical addresses or pfns from the
meminfo array, and use them.  Move for_each_nodebank() to
asm/setup.h alongside the meminfo structure definition.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

There's no point scattering this around the tree, the parsing
of the parameter might as well live beside the code which uses
it.  That also means we can make vmalloc_reserve a static
variable.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

The newly introduced sanity_check_meminfo() function should be
used to collect all validation of the meminfo array, which we
have in bootmem_init().  Move it there.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

The PTRS_PER_PMD != 1 condition can be evaluated with C code and
optimized at compile time.
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

There is no use of this in the whole tree.
Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

The current -march=armv7a is not supported by mainline gcc.

Cc: Paul Brook <paul@codesourcery.com>
Cc: Wei Zhong <weizhong@broadcom.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

... to prevent people being mislead.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

As per the dma_unmap_* calls, we don't touch the cache when a DMA
buffer transitions from device to CPU ownership.  Presently, no
problems have been identified with speculative cache prefetching
which in itself is a new feature in later architectures.  We may
have to revisit the DMA API later for these architectures anyway.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Validate the direction argument like x86 does.  In addition,
validate the dma_unmap_* parameters against those passed to
dma_map_* when using the DMA bounce code.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

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

The dmabounce dma_sync_xxx() implementation have been broken for
quite some time; they all copy data between the DMA buffer and
the CPU visible buffer no irrespective of the change of ownership.
(IOW, a DMA_FROM_DEVICE mapping copies data from the DMA buffer
to the CPU buffer during a call to dma_sync_single_for_device().)

Fix it by getting rid of sync_single(), moving the contents into
the recently created dmabounce_sync_for_xxx() functions and adjusting
appropriately.

This also makes it possible to properly support the DMA range sync
functions.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

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

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

No point having two of these; dma_map_page() can do all the work
for us.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

We can translate a struct page directly to a DMA address using
page_to_dma().  No need to use page_address() followed by
virt_to_dma().
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Update the ARM DMA scatter gather APIs for the scatterlist changes.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

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

This replaces the original cache type decoding printks.  We now
indicate how we're treating the cache which we found, rather
than what we found.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Rather than trying to (inaccurately) decode the cache type from the
registers each time we need to decide what type of cache we have,
use a bitmask initialized early during boot.

Since the setup is a one-off initialization, we can be a little more
clever and take account of the CPU architecture as well.

Note that we continue to achieve the compactness on optimised kernels
by forcing tests to always-false or always-true as appropriate, thereby
allowing the compiler to do build-time code elimination.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

The cache type register found in ARMv5 and later CPUs changes format
and meaning depending on the CPU architecture version.  Currently,
this code:
a) doesn't work for everything - Xscale's are identified as
   'unknown 5'.
b) is not able to tell whether the caches are VIVT or VIPT from the
   cache type.
c) prints rubbish on some ARMv6 and ARMv7+ CPUs.

The two solutions to this are:
1. Add yet more code to decode and print the various different register
   formats.
2. Remove the code altogther.

The code only exists to decode and print the cache parameters.
Increasing the complexity of it just for the sake of a few prinks
isn't worth it.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

http://armlinux.simtec.co.uk/kautobuild/2.6.27-rc5/iop13xx_defconfig/zimage.log

Occurrences  Warning text
339  arch/arm/include/asm/dma-mapping.h:40: warning: return makes pointer from integer without a cast
203  arch/arm/include/asm/dma-mapping.h:45: warning: return makes integer from pointer without a cast
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

This allows assembly files to be crafted to cover all ARM CPU types
rather than erroring out on instructions only in later CPUs.  We
are careful in these files to only execute CPU specific code when
the CPU ID says we can.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

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

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

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

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

... some of which are now in linux/*.h headers.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

This quietens some sparse warnings about phys_initrd_start and
phys_initrd_size.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

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

pc_pointer() was a function to mask the PC for 26-bit ARMs, which
we no longer support.  Remove it.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/kernel/process.c:270:6: warning: symbol 'show_fpregs' was not declared. Should it be static?

This function isn't used, so can be removed.

arch/arm/kernel/setup.c:532:9: warning: symbol 'len' shadows an earlier one
arch/arm/kernel/setup.c:524:6: originally declared here

A function containing two 'len's.

arch/arm/mm/fault-armv.c:188:13: warning: symbol 'check_writebuffer_bugs' was not declared. Should it be static?
arch/arm/mm/mmap.c:122:5: warning: symbol 'valid_phys_addr_range' was not declared. Should it be static?
arch/arm/mm/mmap.c:137:5: warning: symbol 'valid_mmap_phys_addr_range' was not declared. Should it be static?

Missing includes.

arch/arm/kernel/traps.c:71:77: warning: Using plain integer as NULL pointer
arch/arm/mm/ioremap.c:355:46: error: incompatible types in comparison expression (different address spaces)

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

Since the other assembly functions do not seem to save the frame
pointer onto the stack, this patch changes the csum_partial_copy_*
functions to behave in the same way.
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>