The powerpc strncmp implementation does not correctly handle a zero
length, despite the claim in 0119536cd314ef95553604208c25bc35581f7f0a
(Add hand-coded assembly strcmp).

Additionally, all the length arguments are size_t, not int, so use
PPC_LCMPI and eq instead of cmpwi and le throughout.

Signed-off-by: Andreas Schwab <schwab@linux-m68k.org>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Commit 0119536c, which added the assembly version of strncmp to
powerpc, mentions that it adds two instructions to the version from
boot/string.S to allow it to handle len=0. Unfortunately, it doesn't
always return 0 when that is the case. The length is passed in r5, but
the return value is passed back in r3. In certain cases, this will
happen to work. Otherwise it will pass back the address of the first
string as the return value.

This patch lifts the len <= 0 handling code from memcpy to handle that
case.

Reported by: Christian_Sellars@symantec.com
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
CC: <stable@kernel.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Replace ifdef clutter with the PPC_LONG and PPC_LONG_ALIGN macros
for readability.

No change to the generated code.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

We have an assembly version of strncmp for the bootwrapper, but not
for the kernel, so we end up using the C version in the kernel.  This
takes the strncmp code from the bootup and copies it to the kernel
proper, adding two instructions so it copes correctly with len==0.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>

Now that the register names and bit definitions are all in reg.h,
use that instead of processor.h in assembly code in a few places.

Signed-off-by: Paul Mackerras <paulus@samba.org>

This creates the directory structure under arch/powerpc and a bunch
of Kconfig files.  It does a first-cut merge of arch/powerpc/mm,
arch/powerpc/lib and arch/powerpc/platforms/powermac.  This is enough
to build a 32-bit powermac kernel with ARCH=powerpc.

For now we are getting some unmerged files from arch/ppc/kernel and
arch/ppc/syslib, or arch/ppc64/kernel.  This makes some minor changes
to files in those directories and files outside arch/powerpc.

The boot directory is still not merged.  That's going to be interesting.

Signed-off-by: Paul Mackerras <paulus@samba.org>