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: 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,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>

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: Remove MISCREG commented numbers

Having an enum number might be useful in case we wanted to know how many
miscregs we have, but on the other hand it makes it tedious to update
the register list, since every commented number must be bumped. This
patch is removing the comments holding the MISCREG numbers

Change-Id: Ic5aba93885e4b8d6cb3bd6a4c49900b9e5474276
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/13996
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Implement AArch64 ID_AA64MMFR2_EL1 register

This patch implements AArch64 Memory Model Feature Register 2
(from ARMv8.2)

Change-Id: I16d9acaf620fac6d1206e208bd143daec1657daf
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/13066
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Move MiscReg BitUnions into a separate header file

As the number of MiscRegs increases there is the need of a cleaner
header file; this patch is separating miscreg.[cc,hh] where the miscreg
decoding/utility functions are defined/declared from the MiscReg
register types (BitUnion).

Change-Id: I815f53b117b50e47f93aa13d78356ef09d2a2541
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/13065
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Correction for address size in EL1&0 translation

When doing EL0/1 translation in stage2, the
physical address size will be defined by the
hypervisor (via VTCR_EL2.ps, not TCR.ips).

See D10.2.121 of the ARM ARM.

Change-Id: Ic7df97c0f5950a648f7408cde3955a640b562c1d
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/12552
Maintainer: Giacomo Travaglini <giacomo.travaglini@arm.com>

arch-arm: Introduce ARMv8.1 Virtual Timer System Registers

Adding CNTHV_CTL_EL2, CNTHV_CVAL_EL2, CNTHV_TVAL_EL2 System Registers
into the decode tree. They are currently implemented as a generic timer
and produces a warning if accessed.

Change-Id: I1a23035d67f95eeac49d890283e9a0d58426d504
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/11592
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Introduce RAS System Registers

Adding RAS Extension System Registers into the decode tree. They are
currently unimplemented and produce a warning (not failure) if accessed.

Change-Id: I4baeded822c9582a2cb9d5277409b029eb00a962
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/11591
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Fix incorrect t{0,1}sz field in TTBCR

The t0sz and t1sz fields in TTBCR only are only three bits wide unlike
aarch64 which has a 6-bit wide field. The higher bits of the
aarch64-equivalent should be treated as RES0.

Change-Id: I60df73105c34500c0348a44a491c117e9b28f18f
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/11589
Maintainer: Giacomo Travaglini <giacomo.travaglini@arm.com>

arch-arm: Read APSR in User Mode

This patch substitutes reads to the CPSR in user mode (MRS CPSR) to
reads to APSR (Application Program Status Register).
This is the user level alias for the CPSR. The APSR is a subset of the
CPSR.

Change-Id: I18a70693aef6fd305a4c4cb3c6f81f331bc60a2d
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/10602
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Remove unusued MISCREG_A64_UNIMPL

In case the decoder fails to find a suitable MiscReg during a MSR/MRS
in AArch64, MISCREG_UNKNOWN is used, so there is no need for an extra
MISCREG_A64_UNIMPL register.

Change-Id: I7c709fc554e554b39d765dffb7ceb90e33b7c15f
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/10503
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Add E2H bit to HCR_EL2 System register

This patch adds the EL2 Host bit to the HCR_EL2 register. Enables a
configuration where a Host Operating System is running in EL2, and the
Host Operating System's applications are running in EL0.

Change-Id: I92d21ed9f8958c58f135dca1b6a97460ba4c02f9
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/10381
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: Add ARMv8.1 TTBR1_EL2 register

This patch adds ARMv8.1 TTBR1_EL2 register into the decodeAArch64SysReg
table, but stil leaving it unimplemented (Accessing it through MSR/MRS
causes an exception)

Change-Id: I463b86cc544233aa1ee5b2fcba689d6b9f2a874b
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/10063
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arch-arm: IMPLEMENTATION DEFINED register

A new pseudo register has been added to the Misc pool. It is the
implementation defined register. This kinds of registers are covered by
the architecture and must be treated differently than UNIMPLEMENTED
registers: their access can be trapped to EL2 (See HCR.TIDCP bit in the
arm arm).
Some previously undecoded registers in c9,c10,c11 have now this register
type.

Change-Id: Ibfc35982470b9dea0ecf39aaa6b1012a21852f53
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/7922
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: Change function name for banked miscregs

This commit changes the function's name used for retrieving the index of a
security banked register given the flatten index. This will avoid confusion
with flattenRegId, which has a different purpose.

Change-Id: I470ffb55916cb7fc9f78e071a7f2e609c1829f1a
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/7982
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

arm: Don't panic when checking coprocessor read/write permissions

Instructions that use the coprocessor interface check the current
program status to determine whether the current context has the
priviledges to read from/write to the coprocessor. Some modes allow
the execution of coprocessor instructions, some others do not allow it,
while some other modes are unexpected (e.g., executing an AArch32
instruction while being in an AArch64 mode).

Previously we would unconditionally trigger a panic if we were in an
unexpected mode. This change removes the panic and replaces it
with an Undefined Instruction fault that triggers if and when a
coprocessor instruction commits in an unexpected mode. This allows
speculative coprocessor instructions from unexpected modes to execute
but prevents them from gettting committed.

Change-Id: If2776d5bae2471cdbaf76d0e1ae655f501bfbf01
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Rekai Gonzalez Alberquilla <rekai.gonzalezalberquilla@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/2281
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Weiping Liao <weipingliao@google.com>

arm: update AArch{64,32} register mappings

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

arm: add stage2 translation support

Change-Id: I8f7c09c7ec3a97149ebebf4b21471b244e6cecc1

arm: Rewrite ERET to behave according to the ARMv8 ARM

The ERET instruction doesn't set PSTATE correctly in some cases
(particularly when returning to aarch32 code). Among other things,
this breaks EL0 thumb code when using a 64-bit kernel. This changeset
updates the ERET implementation to match the ARM ARM.

Change-Id: I408e7c69a23cce437859313dfe84e68744b07c98
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Nathanael Premillieu <nathanael.premillieu@arm.com>

arm: implement the CONTEXTIDR_EL2 system reg.

arm: Mark some miscregs (timer counter) registers at unverifiable.

The checker can't verify timer registers, so it should just grab the version
from the executing CPU, otherwise it could get a larger value and diverge
execution.

arm: Use MiscRegIndex rather than int when flattening

Some additional type checking to avoid future issues.

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: support 16kb vm granules

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

ARM: add support for TEEHBR access

Thumb2 ARM kernels may access the TEEHBR via thumbee_notifier
in arch/arm/kernel/thumbee.c. The Linux kernel code just seems
to be saving and restoring the register. This patch adds support
for the TEEHBR cp14 register. Note, this may be a special case
when restoring from an image that was run on a system that
supports ThumbEE.

arm: Remove the register mapping hack used when copying TCs

In order to see all registers independent of the current CPU mode, the
ARM architecture model uses the magic MISCREG_CPSR_MODE register to
change the register mappings without actually updating the CPU
mode. This hack is no longer needed since the thread context now
provides a flat interface to the register file. This patch replaces
the CPSR_MODE hack with the flat register interface.

arm: Use a static_assert to test that miscRegName[] is complete

Instead of statically defining miscRegName to contain NUM_MISCREGS
elements, let the compiler determine the length of the array. This
allows us to use a static_assert to test that all registers are listed
in the name vector.

ARM: fix value of MISCREG_CTR returned by readMiscReg()

According to the A15 TRM the value of this register is as follows (assuming 16 word = 64 byte lines)
[31:29] Format - b100 specifies v7
[28] RAZ - b0
[27:24] CWG log2(max writeback size #words) - 0x4 16 words
[23:20] ERG log2(max reservation size #words) - 0x4 16 words
[19:16] DminLine log2(smallest dcache line #words) - 0x4 16 words
[15:14] L1Ip L1 index/tagging policy - b11 specifies PIPT
[13:4] RAZ - b0000000000
[3:0] IminLine log2(smallest icache line #words) - 0x4 16 words

ARM: removed extra white space

Extra white space fixes in miscregs.hh

gcc: Clean-up of non-C++0x compliant code, first steps

This patch cleans up a number of minor issues aiming to get closer to
compliance with the C++0x standard as interpreted by gcc and clang
(compile with std=c++0x and -pedantic-errors). In particular, the
patch cleans up enums where the last item was succeded by a comma,
namespaces closed by a curcly brace followed by a semi-colon, and the
use of the GNU-extension typeof (replaced by templated functions). It
does not address variable-length arrays, zero-size arrays, anonymous
structs, range expressions in switch statements, and the use of long
long. The generated CPU code also has a large number of issues that
remain to be fixed, mainly related to overflows in implicit constant
conversion (due to shifts).

ARM: Add limited CP14 support.

New kernels attempt to read CP14 what debug architecture is available.
These changes add the debug registers and return that none is currently
available.

ARM: update TLB to set request packet ASID field

CP15 c15: enable execution with accesses to c15 registers

Previously, coprocessor accesses to CP15 c15 would fault. This patch
enables accesses but prints out a warning, as the registers are not implemented.

ARM: Implement numcpus bits in L2CTLR register.

ARM: Add two unimplemented miscellaneous registers.

Adds MISCREG_ID_MMFR2 and removes break on access to MISCREG_CLIDR. Both
registers now return values that are consistent with current ARM
implementations.

ARM: Further break up condition code into NZ, C, V bits.

Break up the condition code bits into NZ, C, V registers. These are individually
written and this removes some incorrect dependencies between instructions.

ARM: Remove the saturating (Q) condition code from the renamed register.

Move the saturating bit (which is also saturating) from the renamed register
that holds the flags to the CPSR miscreg and adds a allows setting it in a
similar way to the FP saturating registers. This removes a dependency in
instructions that don't write, but need to preserve the Q bit.

ARM: Break up condition codes into normal flags, saturation, and simd.

This change splits out the condcodes from being one monolithic register
into three blocks that are updated independently. This allows CPUs
to not have to do RMW operations on the flags registers for instructions
that don't write all flags.

ARM: Better RealView/Versatile EB platform support.

Add registers and components to better support the VersatileEB board.
Made the MIDR and SYS_ID register parameters to ArmSystem and RealviewCtrl
respectively.

ARM: Add support for MP misc regs and broadcast flushes.

ARM: Use CPU local lock before sending load to mem system.

This change uses the locked_mem.hh header to handle implementing CLREX. It
simplifies the current implementation greatly.

ARM: Fix checkpoint restoration into O3 CPU and the way O3 switchCpu works.

This change fixes a small bug in the arm copyRegs() code where some registers
wouldn't be copied if the processor was in a mode other than MODE_USER.
Additionally, this change simplifies the way the O3 switchCpu code works by
utilizing TheISA::copyRegs() to copy the required context information
rather than the adhoc copying that goes on in the CPU model. The current code
makes assumptions about the visibility of int and float registers that aren't
true for all architectures in FS mode.

ARM: Cleanup and small fixes to some NEON ops to match the spec.

Only certain bits of the cpacr can be written, some must be equal.
Mult instructions that write the same register should do something sane

ARM: Cleanup implementation of ITSTATE and put important code in PCState.

Consolidate all code to handle ITSTATE in the PCState object rather than
touching a variety of structures/objects.

Arm: Add in a missing miscRegName.

ARM: Implement the Instruction Set Attribute Registers (ISAR).

The ISAR registers describe which features the processor supports.
Transcribe the values listed in section B5.2.5 of the ARM ARM
into the registers as read-only values

ARM: Adds dummy support for a L2 latency miscreg.

O3: Make all instructions that write a misc. register not perform the write until commit.

ARM instructions updating cumulative flags (ARM FP exceptions and saturation
flags) are not serialized.

Added aliases for ARM FP exceptions and saturation flags in FPSCR. Removed
write accesses to the FP condition codes for most ARM VFP instructions: only
VCMP and VCMPE instructions update the FP condition codes. Removed a potential
cause of seg. faults in the O3 model for NEON memory macro-ops (ARM).

ARM: Add comment about the organization of the IT state register

ARM: Seperate out the renamable bits in the FPSCR.

ARM: Implement CPACR register and return Undefined Instruction when FP access is disabled.

ARM: Implement some more misc registers

ARM: Added support for Access Flag and some CP15 regs (V2PCWPR, V2PCWPW, V2PCWUR, V2PCWUW,...)

ARM: Implement support for the IT instruction and the ITSTATE bits of CPSR.

ARM: Some TLB bug fixes.

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

ARM: Implement ARM CPU interrupts

ARM: Make MPIDR return 0 and ignore writes.

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

ARM: Add support for VFP vector mode.

ARM: Implement and update the DFSR and IFSR registers on faults.

ARM: Add in some missing SCTLR fields.

ARM: Warn/ignore when TLB maintenance operations are performed.

ARM: Handle accesses to TLBTR.

ARM: Handle accesses to the DACR.

ARM: Handle accesses to TTBR0 and TTBR1.

ARM: Convert the CP15 registers from MPU to MMU.

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

ARM: Move PC mode bits around so they can be used for exectrace

ARM: Update the set of FP related miscregs.

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

ARM: Ignore/warn on accesses to the DRBAR, DRACR, and DRSR registers.

ARM: Allow access to the RGNR register.

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

ARM: Ignore/warn on accesses to the BPIALLIS and BPIALL registers.

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: Ignore/warn access to the bpimva registers.

ARM: Ignore/warn on accesses to the dccmvac register.

ARM: Ignore/warn on accesses to icimvau.

ARM: Ignore/warn on iciallu.

ARM: Ignore/warn on ICIALLUIS.

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: Decode the unimplemented data barrier CP15 accesses.

These are CP15DSB (Data Synchronization Barrier), and CP15DMB (Data Memory
Barrier).

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: Decode the unimplemented cp15 instruction barrier.

ARM: Ignore accesses to DCCIMVAC.

ARM: Allow accesses to the software thread id registers.

ARM: Allow accesses to the contextidr register.

ARM: Warn about and ignore accesses to DCCISW.

This register is supposed to "Clean and invalidate data or unified cache line
by set/way." Since there isn't a good way to do that, we'll just ignore these
and warn about it.

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

ARM: Replace the "never" condition with the "unconditional" condition.

ARM: Track the current ISA mode using the PC.

ARM: Define a mask to differentiate purely CPSR bits from CondCodes bits.

ARM: Implement fault classes.

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

ARM: Add in more bits for the mon mode.

ARM: Add in spots for the VFP control registers.

ARM: Fill out the printReg function.

ARM: Pull some static code out of the isa desc and create miscregs.hh.