mips: MAAR: Add XPA mode support

When XPA mode is enabled the normally 32-bits MAAR pair registers
are extended to be of 64-bits width as in pure 64-bits MIPS
architecture. In this case the MAAR registers can enable the
speculative loads/stores for addresses of up to 39-bits width.
But in this case the process of the MAAR initialization changes a bit.
The upper 32-bits of the registers are supposed to be accessed by mean
of the dedicated instructions mfhc0/mthc0 and there is a CP0.MAAR.VH
bit which should be set together with CP0.MAAR.VL as indication
of the boundary validity. All of these peculiarities were taken into
account in this commit so the speculative loads/stores would work
when XPA mode is enabled.

Co-developed-by: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Signed-off-by: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-pm@vger.kernel.org
Cc: devicetree@vger.kernel.org
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Update MIPS email addresses

MIPS will soon not be a part of Imagination Technologies, and as such
many @imgtec.com email addresses will no longer be valid. This patch
updates the addresses for those who:

- Have 10 or more patches in mainline authored using an @imgtec.com
email address, or any patches dated within the past year.

- Are still with Imagination but leaving as part of the MIPS business
unit, as determined from an internal email address list.

- Haven't already updated their email address (ie. JamesH) or expressed
a desire to be excluded (ie. Maciej).

- Acked v2 or earlier of this patch, which leaves Deng-Cheng, Matt &
myself.

New addresses are of the form firstname.lastname@mips.com, and all
verified against an internal email address list. An entry is added to
.mailmap for each person such that get_maintainer.pl will report the new
addresses rather than @imgtec.com addresses which will soon be dead.

Instances of the affected addresses throughout the tree are then
mechanically replaced with the new @mips.com address.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Deng-Cheng Zhu <dengcheng.zhu@imgtec.com>
Cc: Deng-Cheng Zhu <dengcheng.zhu@mips.com>
Acked-by: Dengcheng Zhu <dengcheng.zhu@mips.com>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Matt Redfearn <matt.redfearn@mips.com>
Acked-by: Matt Redfearn <matt.redfearn@mips.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: trivial@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Update MIPS email addresses

MIPS will soon not be a part of Imagination Technologies, and as such
many @imgtec.com email addresses will no longer be valid. This patch
updates the addresses for those who:

- Have 10 or more patches in mainline authored using an @imgtec.com
email address, or any patches dated within the past year.

- Are still with Imagination but leaving as part of the MIPS business
unit, as determined from an internal email address list.

- Haven't already updated their email address (ie. JamesH) or expressed
a desire to be excluded (ie. Maciej).

- Acked v2 or earlier of this patch, which leaves Deng-Cheng, Matt &
myself.

New addresses are of the form firstname.lastname@mips.com, and all
verified against an internal email address list. An entry is added to
.mailmap for each person such that get_maintainer.pl will report the new
addresses rather than @imgtec.com addresses which will soon be dead.

Instances of the affected addresses throughout the tree are then
mechanically replaced with the new @mips.com address.

Signed-off-by: Paul Burton <paul.burton@mips.com>
Cc: Deng-Cheng Zhu <dengcheng.zhu@imgtec.com>
Cc: Deng-Cheng Zhu <dengcheng.zhu@mips.com>
Acked-by: Dengcheng Zhu <dengcheng.zhu@mips.com>
Cc: Matt Redfearn <matt.redfearn@imgtec.com>
Cc: Matt Redfearn <matt.redfearn@mips.com>
Acked-by: Matt Redfearn <matt.redfearn@mips.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: trivial@kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17540/
Signed-off-by: James Hogan <jhogan@kernel.org>

MIPS: Separate MAAR V bit into VL and VH for XPA

The MAAR V bit has been renamed VL since another bit called VH is added
at the top of the register when it is extended to 64-bits on a 32-bit
processor with XPA. Rename the V definition, fix the various users, and
add definitions for the VH bit. Also add a definition for the MAARI
Index field.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org

MIPS: Initialise MAARs on secondary CPUs

MAARs should be initialised on each CPU (or rather, core) in the system
in order to achieve consistent behaviour & performance. Previously they
have only been initialised on the boot CPU which leads to performance
problems if tasks are later scheduled on a secondary CPU, particularly
if those tasks make use of unaligned vector accesses where some CPUs
don't handle any cases in hardware for non-speculative memory regions.
Fix this by recording the MAAR configuration from the boot CPU and
applying it to secondary CPUs as part of their bringup.

Reported-by: Doug Gilmore <doug.gilmore@imgtec.com>
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: David Hildenbrand <dahi@linux.vnet.ibm.com>
Cc: linux-kernel@vger.kernel.org
Cc: Aaro Koskinen <aaro.koskinen@iki.fi>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Hemmo Nieminen <hemmo.nieminen@iki.fi>
Cc: Alex Smith <alex.smith@imgtec.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Patchwork: https://patchwork.linux-mips.org/patch/11239/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: Remove "weak" from platform_maar_init() declaration

Weak header file declarations are error-prone because they make every
definition weak, and the linker chooses one based on link order (see
10629d711ed7 ("PCI: Remove __weak annotation from pcibios_get_phb_of_node
decl")).

platform_maar_init() is defined in:

- arch/mips/mm/init.c (where it is marked "weak")
- arch/mips/mti-malta/malta-memory.c (without annotation)

The "weak" attribute on the platform_maar_init() extern declaration applies
to the platform-specific definition in arch/mips/mti-malta/malta-memory.c,
so both definitions are weak, and which one we get depends on link order.

Remove the "weak" attribute from the declaration. That makes the malta
definition strong, so it will always be preferred if it is present.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: linux-mips@linux-mips.org
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Cc: Andrew Bresticker <abrestic@chromium.org>
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/10682/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

MIPS: Initialise MAARs

Add initialisation for Memory Accessibility Attribute Registers. Generic
code cannot know the platform-specific requirements with regards to
speculative accesses, so it simply calls a platform_maar_init function
which platforms with MAARs are expected to implement by calling the
provided write_maar_pair function & returning the number of MAAR pairs
used. A weak default implementation will simply use no MAAR pairs. Any
present but unused MAAR pairs are then marked invalid, effectively
disabling them.

The end result of this patch is that MAARs are all marked invalid, until
platforms implement the platform_maar_init function.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/7331/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>