Modify the user space access functions to support the ColdFire V4e cores
running with MMU enabled.

The ColdFire processors do not support the "moves" instruction used by
the traditional 680x0 processors for moving data into and out of another
address space. They only support the notion of a single address space,
and you use the usual "move" instruction to access that.

Create a new config symbol (CONFIG_CPU_HAS_ADDRESS_SPACES) to mark the
CPU types that support separate address spaces, and thus also support
the sfc/dfc registers and the "moves" instruction that go along with that.

The code is almost identical for user space access, so lets just use a
define to choose either the "move" or "moves" in the assembler code.

Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Acked-by: Matt Waddel <mwaddel@yahoo.com>
Acked-by: Kurt Mahan <kmahan@xmission.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>

The traditional 68000 processors and the newer reduced instruction set
ColdFire processors do not support the 32*32->64 multiply or the 64/32->32
divide instructions. This is not a difference based on the presence of
a hardware MMU or not.

Create a new config symbol to mark that a CPU type doesn't support the
longer multiply/divide instructions. Use this then as a basis for using
the fast 64bit based divide (in div64.h) and for linking in the extra
libgcc functions that may be required (mulsi3, divsi3, etc).

Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>

We have two implementations of the IP checksuming code for the m68k arch.
One uses the more advanced instructions available in 68020 and above
processors, the other uses the simpler instructions available on the
original 68000 processors and the modern ColdFire processors.

This simpler code is pretty much the same as the generic lib implementation
of the IP csum functions. So lets just switch over to using that. That
means we can completely remove the checksum_no.c file, and only have the
local fast code used for the more complex 68k CPU family members.

Signed-off-by: Greg Ungerer <gerg@uclinux.org>

The original 68000 processors cannot copy 16bit or larger quantities from
odd addresses. All newer members of the 68k family (including ColdFire)
can do this.

In the current memcpy implementation after trying to align the destination
address to a 16bit boundary if we end up with an odd source address we go
off and try to copy multi-byte quantities from it. This will trap on the
68000.

The only solution if we end with an odd source address is to byte wise
copy the whole memcpy region. We only need to do this if we are supporting
original 68000 processors.

Signed-off-by: Greg Ungerer <gerg@uclinux.org>

The real difference between the mmu and non-mmu varients of the delay.h
files has nothing to do with having an mmu or not. It is processor family
differences that means slightly different code. Merge the delay_mm.h and
delay_no.h files back into a single file.

The primarly difference we need to deal with is whether the processor
supports a 32bit * 32bit -> 64bit multiply. Without it we need to do some
shift scaling as well as use a 32bit * 32bit -> 32bit multiply. If building
for a multi-CPU type kernel then we must use the simpler mult/shift scaling.

This version of delay code allows the CPU32 family to use a 64bit mul,
since it supports this instruction, the old code did not.

The changes use macros where appropriate to try and optimize constant sized
udelay times. And it removes the use of a fixed lib function for the non-mmu
case. Code size on typical kernel configurations is similar, or only larger
by a few tens of bytes.

Also removed the unused muldiv() code from delay_mm.h.

Build and run tested on ColdFire and ARAnyM. Build tested only on 68328
and 68360 (CPU32).

Signed-off-by: Greg Ungerer <gerg@uclinux.org>

Older m68k-linux compilers will include pre-defined symbols that
confuse what processor it is being targeted for. For example gcc-4.1.2
will pre-define __mc68020__ even if you specify the target processor
as -m68000 on the gcc command line. Newer versions of gcc have this
corrected.

In a few places the m68k code uses defined(__mc68020__) for optimizations
that include instructions that are specific to the CPU 68020 and above.
When compiling with older compilers this will be true even when we have
selected to compile for the older 68000 processors.

Switch to using the kernel processor defines, CONFIG_M68020 and friends.

Signed-off-by: Greg Ungerer <gerg@uclinux.org>

The EXPORT_SYMBOL() of the local lib checksum functions belongs with
the definitions, not in some other random code file. So move then there.

Signed-off-by: Greg Ungerer <gerg@uclinux.org>

We don't need an arch/m68k/lib/checksum.c wrapper to include the correct
mmu or non-mmu version of the checksum code. Let the Makefile just build
the appropriate one.

Signed-off-by: Greg Ungerer <gerg@uclinux.org>

Merging the mmu and non-mmu directories we ended up with duplicate
implementations of memcpy(). One is a little more optimized for the
>= 68020 case, but that can easily be inserted into a single
implementation of memcpy(). Clean up the exporting of this symbol
too, otherwise we end up exporting it twice on a no-mmu build.

Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>

Merging the mmu and non-mmu directories we ended up with duplicate
implementations of memset(). One is a little more optimized for the
>= 68020 case, but that can easily be inserted into a single
implementation of memset(). Clean up the exporting of this symbol
too, otherwise we end up exporting it twice on a no-mmu build.

Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>