Commit Graph

7 Commits

Author SHA1 Message Date
Greg Ungerer 1f7034b961 m68k: allow ColdFire 547x and 548x CPUs to be built with MMU enabled
The ColdFire 547x and 548x CPUs have internal MMU hardware. All code
to support this is now in, so we can build kernels with it enabled.

Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Matt Waddel <mwaddel@yahoo.com>
Acked-by: Kurt Mahan <kmahan@xmission.com>
2011-12-30 10:20:50 +10:00
Geert Uytterhoeven ad8f955daf m68k/Kconfig: Separate classic m68k and coldfire early
While you can build multiplatform kernels for machines with classic
m68k processors, you cannot mix support for classic m68k and coldfire
processors. To avoid such hybrid kernels, introduce CONFIG_M68KCLASSIC
as an antipole for CONFIG_COLDFIRE, and make all specific processor
support depend on one of them.
All classic m68k machine support also needs to depend on this.

The defaults (CONFIG_M68KCLASSIC if MMU, CONFIG_COLDFIRE if !MMU) are
chosen such to make most of the existing configs build and work.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
2011-12-30 10:20:49 +10:00
Greg Ungerer e08d703cc2 m68k: modify user space access functions to support ColdFire CPUs
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>
2011-12-30 10:20:21 +10:00
Greg Ungerer 84f3fb7a2a m68k: handle presence of 64bit mul/div instructions cleanly
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>
2011-12-24 21:47:57 +10:00
Greg Ungerer 7f73bafc46 m68k: simpler m68k and ColdFire CPU's can use generic csum code
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>
2011-12-24 21:47:57 +10:00
Greg Ungerer 5717a02bec m68k: selection of GENERIC_ATOMIC64 is not MMU specific
The selection of the CONFIG_GENERIC_ATOMIC64 option is not specific to the
MMU being present and enabled. It is a property of certain CPU families.
So select it based on those CPU types being selected.

Signed-off-by: Greg Ungerer <gerg@uclinux.org>
2011-12-24 21:47:57 +10:00
Greg Ungerer 0e152d8050 m68k: reorganize Kconfig options to improve mmu/non-mmu selections
The current mmu and non-mmu Kconfig files can be merged to form
a more general selection of options. The current break up of options
is due to the simple brute force merge from the m68k and m68knommu
arch directories.

Many of the options are not at all specific to having the MMU enabled
or not. They are actually associated with a particular CPU type or
platform type.

Ultimately as we support all processors with the MMU disabled we need
many of these options to be selectable without the MMU option enabled.
And likewise some of the ColdFire processors, which currently are only
supported with the MMU disabled, do have MMU hardware, and will need
to have options selected on CPU type, not MMU disabled.

This patch removes the old mmu and non-mmu Kconfigs and instead breaks
up the configuration into four areas: cpu, machine, bus, devices.

The Kconfig.cpu lists all the options associated with selecting a CPU,
and includes options specific to each CPU type as well.

Kconfig.machine lists all options associated with selecting a machine
type. Almost always the machines selectable is restricted by the chosen
CPU.

Kconfig.bus contains options associated with selecting bus types on the
various machine types. That includes PCI bus, PCMCIA bus, etc.

Kconfig.devices contains options for drivers and driver associated
options.

Signed-off-by: Greg Ungerer <gerg@uclinux.org>
2011-10-18 14:22:25 +10:00