MIPS: Add definitions of SegCtl registers and use them

The SegCtl registers are standard for MIPSr3..MIPSr5. Add definitions of
these registers and use them rather than constants

Signed-off-by: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Joshua Kinard <kumba@gentoo.org>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Chris Packham <judge.packham@gmail.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/13290/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: Malta: EVA: Rename 'eva_entry' to 'platform_eva_init'

Rename 'eva_entry' to 'platform_eva_init' as required by the new
'eva_init' macro in the eva.h header. Since this macro is now used
in a platform dependent way, it must not depend on its caller so move
the t1 register initialization inside this macro. Also set the .reorder
assembler option in case the caller may have previously set .noreorder.
This may allow a few assembler optimizations. Finally include missing
headers and document the register usage for this macro.

Reviewed-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: http://patchwork.linux-mips.org/patch/7423/
Signed-off-by: James Hogan <james.hogan@imgtec.com>

MIPS: Malta: EVA: Rename 'eva_entry' to 'platform_eva_init'

Rename 'eva_entry' to 'platform_eva_init' as required by the new
'eva_init' macro in the eva.h header. Since this macro is now used
in a platform dependent way, it must not depend on its caller so move
the t1 register initialization inside this macro. Also set the .reorder
assembler option in case the caller may have previously set .noreorder.
This may allow a few assembler optimizations. Finally include missing
headers and document the register usage for this macro.

Reviewed-by: Paul Burton <paul.burton@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Patchwork: http://patchwork.linux-mips.org/patch/7423/
Signed-off-by: James Hogan <james.hogan@imgtec.com>

MIPS: MT: Remove SMTC support

Nobody is maintaining SMTC anymore and there also seems to be no userbase.
Which is a pity - the SMTC technology primarily developed by Kevin D.
Kissell <kevink@paralogos.com> is an ingenious demonstration for the MT
ASE's power and elegance.

Based on Markos Chandras <Markos.Chandras@imgtec.com> patch
https://patchwork.linux-mips.org/patch/6719/ which while very similar did
no longer apply cleanly when I tried to merge it plus some additional
post-SMTC cleanup - SMTC was a feature as tricky to remove as it was to
merge once upon a time.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: malta: Add support for SMP EVA

Allow secondary cores to program their segment control registers
during smp bootstrap code. This enables EVA on Malta SMP
configurations

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>

MIPS: malta: Configure Segment Control registers for EVA boot

The Malta board aliases 0x80000000 - 0xffffffff to 0x00000000
- 0x7fffffff ignoring the 256 MB IO hole in 0x10000000.
The physical memory is shifted to 0x80000000 so up to 2GB
can be used. Kuseg is expanded to 3GB (due to board limitations
only 2GB can be accessed) and lowmem (kernel space) is expanded to 2GB.

The Segment Control registers are programmed as follows:

Virtual memory Physical memory Mapping
0x00000000 - 0x7fffffff 0x80000000 - 0xfffffffff MUSUK (kuseg)
0x80000000 - 0x9fffffff 0x00000000 - 0x1ffffffff MUSUK (kseg0)
0xa0000000 - 0xbf000000 0x00000000 - 0x1ffffffff MUSUK (kseg1)
0xc0000000 - 0xdfffffff - MK (kseg2)
0xe0000000 - 0xffffffff - MK (kseg3)

The location of exception vectors remain the same since 0xbfc00000
(traditional exception base) still maps to 0x1fc00000 physical.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>

MIPS: Move headfiles to new location below arch/mips/include

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>