MIPS: Warn if vector register partitioning is implemented

No current systems implementing MSA include support for vector register
partitioning which makes it somewhat difficult to implement support for
it in the kernel. Thus for the moment the kernel includes no such
support. However if the kernel were to be run on a system which
implemented register partitioning then it would not function correctly,
mishandling MSA disabled exceptions. Print a warning if run on a system
with vector register partitioning implemented to indicate this problem
should it occur.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6494/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS: Save/restore MSA context around signals

This patch extends sigcontext in order to hold the most significant 64
bits of each vector register in addition to the MSA control & status
register. The least significant 64 bits are already saved as the scalar
FP context. This makes things a little awkward since the least & most
significant 64 bits of each vector register are not contiguous in
memory. Thus the copy_u & insert instructions are used to transfer the
values of the most significant 64 bits via GP registers.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6533/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS: Add MIPS P5600 PRid and cputype identifiers

Add a Processor ID and CPU type for the MIPS P5600 core.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6407/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS: Add cases for CPU_P5600

Add a CPU_P5600 case to various switch statements, doing the same thing
as for CPU_PROAPTIV.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6408/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS: Add MIPS P5600 probe support

Add a case in cpu_probe_mips for the MIPS P5600 processor ID, which sets
the CPU type to the new CPU_P5600.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6409/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS: Allow FTLB to be turned on for CPU_P5600

Allow FTLB to be turned on or off for CPU_P5600 as well as CPU_PROAPTIV.
The existing if statement is converted into a switch to allow for future
expansion.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/6411/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS: OProfile: Add CPU_P5600 cases

Add a CPU_P5600 cpu type case in oprofile_arch_init() to use the MIPS
model, and in mipsxx_init() to set the cpu_type string to "mips/P5600".

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Reviewed-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Robert Richter <rric@kernel.org>
Cc: oprofile-list@lists.sf.net
Patchwork: https://patchwork.linux-mips.org/patch/6410/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
MIPS: Kconfig: Add Kconfig symbols for EVA support

Add basic Kconfig support for EVA. Not selectable by any platform
at this point.

Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
MIPS: asm: Add prefetch instruction for EVA

EVA can use the PREFE instruction to perform the virtual address
translation using the user mapping of the address rather than the
kernel mapping.

Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
MIPS: asm: Add wrappers for EVA/non-EVA instructions

EVA uses specific instructions for accessing user memory.
Instead of polluting the kernel with numerous #ifdef CONFIG_EVA
we add wrappers for all the instructions that need special
handling when EVA is enabled.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
MIPS: futex: Add EVA support for futex operations

Use LLE/SCE instructions for performing an address translation for
userspace when EVA is enabled.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
MIPS: uapi: inst: Add new EVA opcodes

Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
MIPS: uapi: inst: Add instruction format for SPECIAL3 instructions

Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
MIPS: kernel: scall32-o32: Use EVA wrappers to fetch syscall arguments

Arguments 4-8 are stored on user's stack, so use the EVA instructions
to fetch them if EVA is enabled.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
MIPS: kernel: traps: Whitespace clean up

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
MIPS: traps: Set correct address limit for breakpoints and traps

When a breakpoint or trap happens when operating in kernel mode but
on users behalf (eg syscall) it is necessary to change the address
limit to KERNEL_DS so any address checking can be bypassed and print
the correct stack trace.

Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
MIPS: lib: strnlen_user: Use macro to build the strnlen_user symbol

Build the __strnlen_user symbol using a macro. In EVA mode we will
need to use similar code to do the userspace load operations so
it is better if we use a macro to avoid code duplications.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
MIPS: lib: strnlen_user: Add EVA support

In non-EVA mode, a strlen_user* alias is used for the
strlen_kernel* symbols since the code is identical. In EVA
mode, a new strlen_user* symbol is used which uses the EVA
specific instructions to load values from userspace.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
MIPS: lib: strlen_user: Use macro to build the strlen_user symbol

Build the __strlen_user symbol using a macro. In EVA mode we will
need to use similar code to do the userspace load operations so
it is better if we use a macro to avoid code duplications.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
MIPS: lib: strlen_user: Add EVA support

In non-EVA mode, strlen_user* aliases are used for the
strlen_kernel* symbols since the code is identical. In EVA
mode, new strlen_user* symbols are used which use the EVA
specific instructions to load values from userspace.

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