This is a small subset of string functions needed by commits to come.
Except for memcpy() which is unchanged from its original location, their
implementation is meant to be small, and -Os is enforced to prevent gcc
from doing pointless loop unrolling.

Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Tested-by: Dave Martin <dave.martin@linaro.org>
Tested-by: Thomas Abraham <thomas.abraham@linaro.org>

If decompress() returns an error without calling error(), we must
not attempt to boot the resulting kernel.

Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Tested-by: Tony Lindgren <tony@atomide.com>

The return value for decompress_kernel() is no longer used.  Furthermore,
this was obtained and stored in a variable called output_ptr which is
a complete misnomer for what is actually the size of the decompressed
kernel image.  Let's get rid of it.

Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Tested-by: Tony Lindgren <tony@atomide.com>

The inline assembly differences for v6 vs. v7 are purely
optimizations. On a v7 processor, an mrc with the pc sets the
condition codes to the 28-31 bits of the register being read. It
just so happens that the TX/RX full bits the DCC support code is
testing for are high enough in the register to be put into the
condition codes. On a v6 processor, this "feature" isn't
implemented and thus we have to do the usual read, mask, test
operations to check for TX/RX full. Thus, we can drop the v7
implementation and just use the v6 implementation for both.

Cc: Tony Lindgren <tony@atomide.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Introduce a CPU_V6K configuration option for platforms to select if they
have a V6K CPU core.  This allows us to identify whether we need to
support ARMv6 CPUs without the V6K SMP extensions at build time.

Currently CPU_V6K is just an alias for CPU_V6, and all places which
reference CPU_V6 are replaced by (CPU_V6 || CPU_V6K).

Select CPU_V6K from platforms which are known to be V6K-only.

Acked-by: Tony Lindgren <tony@atomide.com>
Tested-by: Sourav Poddar <sourav.poddar@ti.com>
Tested-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

I tried to get this running to debug the regression introduced by
e7db7b4 without success.  But this has several problems that make it
hard to fix:

  - lib/decompress_inflate.c includes in-kernel headers that make
    it difficult to compile for user space.
  - the binary formats changed both in kernel and user space and
    at least for the kernel side there isn't only a single
    variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>

Commit 5de813b6 (ARM: Eliminate decompressor -Dstatic= PIC hack) among
other things changed the declared type of the error() function to an
extern, conflicting with the forward declartion in the Samsung
plat/uncompress.h which appears to have been relying on the static
being defined away, causing build failures since error() ends up with
a GOT relocation but the linker script discards all GOT relocated
data and functions:

arch/arm/boot/compressed/decompress.o: In function `gunzip':
/home/broonie/git/linux-2.6/arch/arm/boot/compressed/../../../../lib/decompress_
+inflate.c:68: undefined reference to `error'

and so on. Fix this by moving the declaration into uncompress/misc.c
where it is shared with the rest of the code, correcting the definition
as we go.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

We used to build decompressors with -Dstatic= to avoid any local data
being generated.  The problem is that local data generates GOTOFF
relocations, which means we can't relocate the data relative to the
text segment.

Global data, on the other hand, goes through the GOT, and can be
relocated anywhere.

Unfortunately, with the new decompressors, this presents a problem
since they declare static data within functions, and this leads to
stack overflow.

Fix this by separating out the decompressor code into a separate file,
and removing 'static' from BSS data in misc.c.

Also, discard the .data section - this means that should we end up
with read/write initialized data, the decompressor will fail to link
and the problem will be obvious.

Acked-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>