arch-arm: Add explicit AArch64 MiscReg banking

Change-Id: I89836d14491a51b1573f45c8012e3ad12b107d24
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/20623
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

arch-arm: adding register control flags enabling LSE implementation

Added changes on arch-arm architecture to accept Atomic instructions
following ARM v8.1 documentation. That includes enabling atomic bit
in ID registers and add have_lse variable into arm system.

Change-Id: Ic28d3215d74ff129142fb51cb2fa217d3b1482de
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19809
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Maintainer: Giacomo Travaglini <giacomo.travaglini@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

arch-arm: Implement ARMv8.1-PAN, Privileged access never

ARMv8.1-PAN adds a new bit to PSTATE. When the value of this PAN state
bit is 1, any privileged data access from EL1 or EL2 to a virtual memory
address that is accessible at EL0 generates a Permission fault.
This feature is mandatory in ARMv8.1 implementations.
This feature is supported in AArch64 and AArch32 states.
The ID_AA64MMFR1_EL1.PAN, ID_MMFR3_EL1.PAN, and ID_MMFR3.PAN fields
identify the support for ARMv8.1-PAN.

Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Change-Id: I94a76311711739dd2394c72944d88ba9321fd159
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/19729
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

arch-arm: Expose haveGicv3CPUInterface to the ISA interface

Change-Id: I36232b7618ad875983f34b741c51f12ddb9ae166
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17989
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>

arch-arm,cpu: Add initial support for Arm SVE

This changeset adds initial support for the Arm Scalable Vector Extension
(SVE) by implementing:
- support for most data-processing instructions (no loads/stores yet);
- basic system-level support.

Additional authors:
- Javier Setoain <javier.setoain@arm.com>
- Gabor Dozsa <gabor.dozsa@arm.com>
- Giacomo Travaglini <giacomo.travaglini@arm.com>

Thanks to Pau Cabre for his contribution of bugfixes.

Change-Id: I1808b5ff55b401777eeb9b99c9a1129e0d527709
Signed-off-by: Giacomo Gabrielli <giacomo.gabrielli@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/13515
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch,cpu: Add vector predicate registers

Latest-gen. vector/SIMD extensions, including the Arm Scalable Vector
Extension (SVE), introduce the notion of a predicate register file.
This changeset adds this feature across architectures and CPU models.

Change-Id: Iebcadbad89c0a582ff8b1b70de353305db603946
Signed-off-by: Giacomo Gabrielli <giacomo.gabrielli@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/13715
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

cpu, arch, arch-arm: Wire unused VecElem code in the O3 model

VecElem code had been introduced in order to simulate change of renaming
for vector registers. Most of the work is happening on the rename_map
switchRenameMode. Change of renaming can happen after a squash in the
pipeline.
This patch is also changing the interface to the ISA part so that
a PCState is used instead of ISA in order to check if rename mode
has changed.

Change-Id: I8af795d771b958e0a0d459abfeceff5f16b4b5d4
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15601

arch: cpu: Stop passing around misc registers by reference.

These values are all basic integers (specifically uint64_t now), and
so passing them by const & is actually less efficient since there's a
extra level of indirection and an extra value, and the same sized value
(a 64 bit pointer vs. a 64 bit int) is being passed around.

Change-Id: Ie9956b8dc4c225068ab1afaba233ec2b42b76da3
Reviewed-on: https://gem5-review.googlesource.com/c/13626
Maintainer: Gabe Black <gabeblack@google.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

arm: Get rid of some register type definitions.

These are IntReg, FloatReg, FloatRegBits, and MiscReg. These have been
supplanted by the global types RegVal and FloatRegVal.

Change-Id: Ief1cd85d0eff7156282ddb1ce168a2a5677f7435
Reviewed-on: https://gem5-review.googlesource.com/c/13625
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Maintainer: Giacomo Travaglini <giacomo.travaglini@arm.com>

arch-arm: Fix usage of RegId constructor for VecElem

RegId() constructor requires three arguments in case of a VecElem
register: the class, the vector index and the element index inside the
vector, otherwise it panics.

Change-Id: Ic842df4dcddaffa83b211aa6e1dd1953cafa4951
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Giacomo Gabrielli <giacomo.gabrielli@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15615
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

dev-arm: Add a GICv3 model

Change-Id: Ib0067fc743f84ff7be9f12d2fc33ddf63736bdd1
Reviewed-on: https://gem5-review.googlesource.com/c/13436
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Maintainer: Giacomo Travaglini <giacomo.travaglini@arm.com>

arch-arm: Implement AArch32 RVBAR

RVBAR has been added to the system register list since ARMv8.0-A. It is
implemented only if the highest Exception Level is different (minor)
than EL3. If that's not the case, MVBAR is used. Since the two
registers are mutually exclusive (depending on the presence of EL3),
they share the same coprocessor numbers:

p15, 0, c12, c0, 1

Rather than introducing a new register alias, we overload MVBAR so that
it is treated as RVBAR if ArmSystem::highestEL() < EL3. This patch is
changing the MiscReg info so that EL1 or EL2 access MVBAR (as RVBAR).

N.B MVBAR is RW, whereas RVBAR is RO

Change-Id: Ida3070413fd151ce79c446e99a2a389298d5f5bd
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/13999
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Refactor ISA::clear by adding a ISA::clear32 method

The patch is also moving some initialization code to be used
by AArch64 as well since the registers are mapped to AArch64 ones.

Change-Id: I0089df25275434172c6e0e9cb125ee535c04d1b8
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/13997
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Add have_crypto System parameter

This patch adds the have_crypto ArmSystem parameter for enabling crypto
extension. This is done by modifying the AArch32/AArch64 ID registers
at startup time.

Change-Id: I6eefb7e6f6354802a14ea639ad53b75f8e1e11c5
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/13252
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>

arch-arm: Init AArch64 ID registers in SE mode

One of the auxv vector's flag is the HWCAP, whose bits match the content
of several arm ID registers. This patch factors out AArch64 ID
registers init into a separate method and creates the symmetric AArch32
ID register init as well, so that we get a meaningful auxiliary vector
in SE mode.

Change-Id: I52bdb31b67508c4447558ebd7ca743733a69280e
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/13064
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

Fix SConstruct for asan build

Sometimes it's easier to debug gem5 built with ASan enabled. This CL fixes
some build error when using --with-asan.

Bug: None
Test: ./scripts/build_gem5 --with-asan --with-ubsan build/ARM/gem5.debug

Change-Id: Iaaaaebc3f25749e11f97bf454ddd0153b3de56e7
Reviewed-on: https://gem5-review.googlesource.com/12511
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com>
Maintainer: Anthony Gutierrez <anthony.gutierrez@amd.com>

arm: Add support for tracking TCs in ISA devices

ISA devices typically need to keep track of the thread context they
are associated with. Among other things, this is required for
interrupt delivery. Add a BaseISADevice:setThreadContext() method to
wire such models to the right thread context.

Change-Id: Iad354d176c0c4c4e34c6ab8b5acaee0b69da0406
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/12399
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>

arch-arm: ISA param for treating MISCREG_IMPDEF_UNIMPL as NOP

In the Arm ISA there are some sys reg numbers which are reserved for
implementation defined registers. The default behaviour is to to treat
them as unimplemented registers. It is now possible to change this
behaviour at runtime and treat them as NOP. In this way an access to
those register won't make simulation fail.

Change-Id: I0d108299a6d5aa81fcdabdaef04eafe46df92343
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/10504
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Adding MiscReg Priv (EL1) global flag

This patch introduces a single global flag for setting RW access
permission at EL1 level, in either secure and non-secure mode.

Change-Id: I35df66a73349044ca996b5c04c5a2476f3a7abdf
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/10042
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Distinguish IS TLBI from non-IS

TLBI broadcasting was the default implementation of most of TLBI
instructions. This patch applies the broadcasting behaviour only to the
Inner-Shareable subset, while simpler TLB invalidation instructions only
affect the PE that executes them.

Change-Id: Idb01d0d4f593131f657e8fc9668112de8e4ccdcb
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/9182
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Created function for TLB ASID Invalidation

This patch is intended to avoid code duplication and extends the set of
TLBI ISA functions adding the entry invalidation by ASID match.

Change-Id: I9bcb498059ea480dd2118639c7b3c64fea80a5e1
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/9181
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Adding IPA-Based Invalidating instructions

This patch introduces the TLB IPA-Based invalidating instructions in
aarch32. In the entry selection policy the level of translation is not
taken into account.
This means that no difference stands between (e.g.) TLBIIPAS2 and
TLBIPAS2L.

Change-Id: Ieeb54665480874d2041056f356d86448c45043cb
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/8822
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Arch regs and pseudo regs distinction

A new identifier has been introduced: NUM_PHYS_MISCREGS, which is used
as a boundary for the number of physical (real) Misc registers in the
system. Pseudo registers (like CP15_UNIMPL) have been moved after the
NUM_PHYS_MISCREGS identifier, so that their enum number is
(NUM_PHYS_MISCREGS < number < NUM_MISCREGS). Moving away those
registers has created some free slots that can be used for future Misc
register implementation.
SERIALIZE and UNSERIALIZE now only save/restore PHYSICAL Misc Registers.
This allows us to define as many pseudo registers as we want without
being concerned about checkpoint compatibility.

Change-Id: I7e297b814eeaa4bee640e81bee625fb66710af45
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/7921
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: understandably initialize register permissions

Move massive initialization routine to the bottom of miscregs.cc.
Additionally, share register metadata across ISA instances by
making lookUpMiscReg a static member of the ISA and only
initializing it once.

Change-Id: I6d6ab26200c4e781151cc6efd97ce2420e2bf4cc
Signed-off-by: Curtis Dunham <Curtis.Dunham@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jack Travaglini <giacomo.travaglini@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/6803
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arm: extend MiscReg metadata structures

Implement proper handling of RES0/RES1 and RAZ/RAO bitfields.

Change-Id: I344c32c3fb1d142acfb0521ba3590ddd2b1f5360
Signed-off-by: Curtis Dunham <Curtis.Dunham@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jack Travaglini <giacomo.travaglini@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/6802
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: understandably initialize register mappings

The mappings for sharing a backing store between AArch32
and AArch64 system registers are made clearer using an
initializer object.

Change-Id: I29dcfab2797b4d36b3182342997edffde334a291
Signed-off-by: Curtis Dunham <Curtis.Dunham@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Jack Travaglini <giacomo.travaglini@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/6801
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

cpu: Added interface for vector reg file

This patch adds some more functionality to the cpu model and the arch to
interface with the vector register file.

This change consists mainly of augmenting ThreadContexts and ExecContexts
with calls to get/set full vectors, underlying microarchitectural elements
or lanes. Those are meant to interface with the vector register file. All
classes that implement this interface also get an appropriate implementation.

This requires implementing the vector register file for the different
models using the VecRegContainer class.

This change set also updates the Result abstraction to contemplate the
possibility of having a vector as result.

The changes also affect how the remote_gdb connection works.

There are some (nasty) side effects, such as the need to define dummy
numPhysVecRegs parameter values for architectures that do not implement
vector extensions.

Nathanael Premillieu's work with an increasing number of fixes and
improvements of mine.

Change-Id: Iee65f4e8b03abfe1e94e6940a51b68d0977fd5bb
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
[ Fix RISCV build issues and CC reg free list initialisation ]
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/2705

cpu: Simplify the rename interface and use RegId

With the hierarchical RegId there are a lot of functions that are
redundant now.

The idea behind the simplification is that instead of having the regId,
telling which kind of register read/write/rename/lookup/etc. and then
the function panic_if'ing if the regId is not of the appropriate type,
we provide an interface that decides what kind of register to read
depending on the register type of the given regId.

Change-Id: I7d52e9e21fc01205ae365d86921a4ceb67a57178
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
[ Fix RISCV build issues ]
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/2702

arm: miscreg refactoring

Change-Id: I4e9e8f264a4a4239dd135a6c7a1c8da213b6d345
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>

arm: update AArch{64,32} register mappings

Change-Id: Idaaaeb3f7b1a0bdbf18d8e2d46686c78bb411317
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>

arm: enable EL2 support

Change-Id: I59fa4fae98c33d9e5c2185382e1411911d27d341

isa: Add parameter to pick different decoder inside ISA

The decoder is responsible for splitting instructions in micro
operations (uops). Given that different micro architectures may split
operations differently, this patch allows to specify which micro
architecture each isa implements, so different cores in the system can
split instructions differently, also decoupling uop splitting
(microArch) from ISA (Arch). This is done making the decodification
calls templates that receive a type 'DecoderFlavour' that maps the
name of the operation to the class that implements it. This way there
is only one selection point (converting the command line enum to the
appropriate DecodeFeatures object). In addition, there is no explicit
code replication: template instantiation hides that, and the compiler
should be able to resolve a number of things at compile-time.

revert 5af8f40d8f2c

cpu: implements vector registers

This adds a vector register type. The type is defined as a std::array of a
fixed number of uint64_ts. The isa_parser.py has been modified to parse vector
register operands and generate the required code. Different cpus have vector
register files now.

sim: Refactor the serialization base class

Objects that are can be serialized are supposed to inherit from the
Serializable class. This class is meant to provide a unified API for
such objects. However, so far it has mainly been used by SimObjects
due to some fundamental design limitations. This changeset redesigns
to the serialization interface to make it more generic and hide the
underlying checkpoint storage. Specifically:

* Add a set of APIs to serialize into a subsection of the current
object. Previously, objects that needed this functionality would
use ad-hoc solutions using nameOut() and section name
generation. In the new world, an object that implements the
interface has the methods serializeSection() and
unserializeSection() that serialize into a named /subsection/ of
the current object. Calling serialize() serializes an object into
the current section.

* Move the name() method from Serializable to SimObject as it is no
longer needed for serialization. The fully qualified section name
is generated by the main serialization code on the fly as objects
serialize sub-objects.

* Add a scoped ScopedCheckpointSection helper class. Some objects
need to serialize data structures, that are not deriving from
Serializable, into subsections. Previously, this was done using
nameOut() and manual section name generation. To simplify this,
this changeset introduces a ScopedCheckpointSection() helper
class. When this class is instantiated, it adds a new /subsection/
and subsequent serialization calls during the lifetime of this
helper class happen inside this section (or a subsection in case
of nested sections).

* The serialize() call is now const which prevents accidental state
manipulation during serialization. Objects that rely on modifying
state can use the serializeOld() call instead. The default
implementation simply calls serialize(). Note: The old-style calls
need to be explicitly called using the
serializeOld()/serializeSectionOld() style APIs. These are used by
default when serializing SimObjects.

* Both the input and output checkpoints now use their own named
types. This hides underlying checkpoint implementation from
objects that need checkpointing and makes it easier to change the
underlying checkpoint storage code.

dev, arm: Refactor and clean up the generic timer model

This changeset cleans up the generic timer a bit and moves most of the
register juggling from the ISA code into a separate class in the same
source file as the rest of the generic timer. It also removes the
assumption that there is always 8 or fewer CPUs in the system. Instead
of having a fixed limit, we now instantiate per-core timers as they
are requested. This is all in preparation for other patches that add
support for virtual timers and a memory mapped interface.

arm: Remove unnecessary boot uncachability

With the recent patches addressing how we deal with uncacheable
accesses there is no longer need for the work arounds put in place to
enforce certain sections of memory to be uncacheable during boot.

arm: Don't truncate 16-bit ASIDs to 8 bits

The ISA code sometimes stores 16-bit ASIDs as 8-bit unsigned integers
and has a couple of inverted checks that mask out the high 8 bits of
an ASID if 16-bit ASIDs have been /enabled/. This changeset fixes both
of those issues.

arm: Fix multi-system AArch64 boot w/caches.

Automatically extract cpu release address from DTB file.
Check SCTLR_EL1 to verify all caches are enabled.

arm: Add a model of an ARM PMUv3

This class implements a subset of the ARM PMU v3 specification as
described in the ARMv8 reference manual. It supports most of the
features of the PMU, however the following features are known to be
missing:

* Event filtering (e.g., from different privilege levels).
* Access controls (the PMU currently ignores the execution level).
* The chain counter (event no. 0x1E) is unimplemented.

The PMU itself does not implement any events, it merely provides an
interface for the configuration scripts to hook up probes that drive
events. Configuration scripts should call addEventProbe() to configure
custom events or high-level methods to configure architected
events. The Python implementation of addEventProbe() automatically
delays event type registration until after instantiation.

In order to support CPU switching and some combined counters (e.g.,
memory references synthesized from loads and stores), the PMU allows
multiple probes per event type. When creating a system that switches
between CPU models that share the same PMU, PMU events for all of the
CPU models can be registered with the PMU.

Kudos to Matt Horsnell for the initial gem5 implementation of the PMU.

arm: use condition code registers for ARM ISA

Analogous to ee049bf (for x86). Requires a bump of the checkpoint version
and corresponding upgrader code to move the condition code register values
to the new register file.

arm: Add support for ARMv8 (AArch64 & AArch32)

Note: AArch64 and AArch32 interworking is not supported. If you use an AArch64
kernel you are restricted to AArch64 user-mode binaries. This will be addressed
in a later patch.

Note: Virtualization is only supported in AArch32 mode. This will also be fixed
in a later patch.

Contributors:
Giacomo Gabrielli (TrustZone, LPAE, system-level AArch64, AArch64 NEON, validation)
Thomas Grocutt (AArch32 Virtualization, AArch64 FP, validation)
Mbou Eyole (AArch64 NEON, validation)
Ali Saidi (AArch64 Linux support, code integration, validation)
Edmund Grimley-Evans (AArch64 FP)
William Wang (AArch64 Linux support)
Rene De Jong (AArch64 Linux support, performance opt.)
Matt Horsnell (AArch64 MP, validation)
Matt Evans (device models, code integration, validation)
Chris Adeniyi-Jones (AArch64 syscall-emulation)
Prakash Ramrakhyani (validation)
Dam Sunwoo (validation)
Chander Sudanthi (validation)
Stephan Diestelhorst (validation)
Andreas Hansson (code integration, performance opt.)
Eric Van Hensbergen (performance opt.)
Gabe Black

arch: Make all register index flattening const

This patch makes all the register index flattening methods const for
all the ISAs. As part of this, readMiscRegNoEffect for ARM is also
made const.

cpu: add a condition-code register class

Add a third register class for condition codes,
in parallel with the integer and FP classes.
No ISAs use the CC class at this point though.

scons: Add warning for overloaded virtual functions

Fix the ISA startup warnings

x86: Changes to decoder, corrects 9376
The changes made by the changeset 9376 were not quite correct. The patch made
changes to the code which resulted in decoder not getting initialized correctly
when the state was restored from a checkpoint.

This patch adds a startup function to each ISA object. For x86, this function
sets the required state in the decoder. For other ISAs, the function is empty
right now.

arch: Move the ISA object to a separate section

After making the ISA an independent SimObject, it is serialized
automatically by the Python world. Previously, this just resulted in
an empty ISA section. This patch moves the contents of the ISA to that
section and removes the explicit ISA serialization from the thread
contexts, which makes it behave like a normal SimObject during
serialization.

Note: This patch breaks checkpoint backwards compatibility! Use the
cpt_upgrader.py utility to upgrade old checkpoints to the new format.

arch: Make the ISA class inherit from SimObject

The ISA class on stores the contents of ID registers on many
architectures. In order to make reset values of such registers
configurable, we make the class inherit from SimObject, which allows
us to use the normal generated parameter headers.

This patch introduces a Python helper method, BaseCPU.createThreads(),
which creates a set of ISAs for each of the threads in an SMT
system. Although it is currently only needed when creating
multi-threaded CPUs, it should always be called before instantiating
the system as this is an obvious place to configure ID registers
identifying a thread/CPU.

trace: reimplement the DTRACE function so it doesn't use a vector
At the same time, rename the trace flags to debug flags since they
have broader usage than simply tracing. This means that
--trace-flags is now --debug-flags and --trace-help is now --debug-help

ARM: Add checkpointing support

ARM: Clean up flattening for SPSR adding

ARM: Move the ISA "clear" function into isa.cc.

ARM: Some TLB bug fixes.

ARM: Move Miscreg functions out of isa.hh

ARM: Implement the ARM TLB/Tablewalker. Needs performance improvements.

ARM: Implement ARM CPU interrupts

ARM: Make various bits of the FP control registers read only.

ARM: Make MPIDR return 0 and ignore writes.

ARM: Set the value of the MVFR0 and MVFR1 registers.

ARM: Handle accesses to TLBTR.

ARM: Convert the CP15 registers from MPU to MMU.

ARM: Add some support for wfi/wfe/yield/etc

ARM: Add a traceflag to print cpsr

ARM: Ignore attempts to disable coprocessors that aren't implemented anyway.

ARM: Allow flattening into any mode.

ARM: Make the MPUIR register report that 1 unified data region is supported.

ARM: Ignore/warn when CSSELR or CCSIDR are accessed.

These registers provide information about the caches. Since we can't provide
that information, these will be harmlessly inert.

ARM: Add support for the clidr register.

This register will always report 0 caches as implemented. It's not clear how
to find out how many there really are when dealing with an arbitrary
hierarchy.

ARM: Implement a stub of CPACR.

This register controls access to the coprocessors. This doesn't actually
implement it, it allows writes which don't turn anything off. In other words,
it allows the simulated program to ask for what it already has.

ARM: Actually write the value of sctlr in ISA.clear().

ARM: Implement a function to decode CP15 registers to MiscReg indices.

ARM: Track the current ISA mode using the PC.

ARM: Hook up the moded versions of the SPSR.

These registers can be accessed directly, or through MISCREG_SPSR which will
act as whichever SPSR is appropriate for the current mode.

ARM: Implement fault classes.

Implement some fault classes using the curriously recurring template pattern,
similar to SPARCs.

ARM: Support forcing load/store multiple to use user registers.

ARM: Add in more bits for the mon mode.

ARM: Initialize processes in user mode.

I accidentally left in a change to test using int registers in system mode.
This change reverts that.

ARM: Implement the shadow registers using register flattening.

ISA: Fix compilation.

ARM: Initialize the CPSR so that we're in user mode.

ARM: Fold the MiscRegFile all the way into the ISA object.

Registers: Collapse ARM and MIPS regfile directories.

Registers: Add an ISA object which replaces the MiscRegFile.
This object encapsulates (or will eventually) the identity and characteristics
of the ISA in the CPU.