KScratch<n> Registers (CP0 Register 31, Selects 2 to 7)

The KScratch registers are read/write registers available for scratch pad
storage by kernel mode software. They are 32-bits in width for 32-bit
processors and 64-bits for 64-bit processors.

CP0Config4.KScrExist[2:7] bits indicate presence of CP0_KScratch1-6 registers.
For Release 6, all KScratch registers are required.
Signed-off-by: NLeon Alrae <leon.alrae@imgtec.com>
Reviewed-by: NYongbok Kim <yongbok.kim@imgtec.com>

Remove the functions gen_load_ACX and gen_store_ACX, which appear to have
been unused since they were first introduced many years ago. These functions
were the only places using the cpu_ACX[] array of TCG globals, so remove
that and its accompanying regnames_ACX[] as well.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NRichard Henderson <rth@twiddle.net>
Signed-off-by: NLeon Alrae <leon.alrae@imgtec.com>

The function check_mips64() is only used if TARGET_MIPS64 is defined;
add an ifdef guard to its definition to avoid warnings about it being
unused in other configurations.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NRichard Henderson <rth@twiddle.net>
Signed-off-by: NLeon Alrae <leon.alrae@imgtec.com>

Commit 240ce26a broke MIPS16 and microMIPS support as it didn't
care those branches and jumps don't have delay slot in
MIPS16 and microMIPS.

This patch introduces a new argument delayslot_size to the
gen_compute_branch() indicating size of delay slot {0, 2, 4}.
And the information is used to call handle_delay_slot() forcingly
when no delay slot is required.

There are some microMIPS branch and jump instructions that requires
exact size of instruction in the delay slot. For indicating
these instructions, MIPS_HFLAG_BDS_STRICT flag is introduced.

Those fictional branch opcodes defined to support MIPS16 and
microMIPS are no longer needed.
Signed-off-by: NYongbok Kim <yongbok.kim@imgtec.com>
Tested-by: NJonas Gorski <jogo@openwrt.org>
Reviewed-by: NLeon Alrae <leon.alrae@imgtec.com>
[leon.alrae@imgtec.com: cosmetic changes]
Signed-off-by: NLeon Alrae <leon.alrae@imgtec.com>

Update OPC_SYNCI with BS_STOP, in order to handle the instructions which saved
in the same TB of the store instruction.
Signed-off-by: NDongxue Zhang <elta.era@gmail.com>
Reviewed-by: NYongbok Kim <yongbok.kim@imgtec.com>
[leon.alrae@imgtec.com: update microMIPS SYNCI as well]
Signed-off-by: NLeon Alrae <leon.alrae@imgtec.com>

Signed-off-by: NYongbok Kim <yongbok.kim@imgtec.com>
Signed-off-by: NLeon Alrae <leon.alrae@imgtec.com>
Reviewed-by: NAurelien Jarno <aurelien@aurel32.net>

Status.FR bit must be ignored on write and read as 1 when an implementation of
Release 6 of the Architecture in which a 64-bit floating point unit is
implemented.
Signed-off-by: NLeon Alrae <leon.alrae@imgtec.com>
Reviewed-by: NYongbok Kim <yongbok.kim@imgtec.com>

Signed-off-by: NYongbok Kim <yongbok.kim@imgtec.com>
Signed-off-by: NLeon Alrae <leon.alrae@imgtec.com>
Reviewed-by: NAurelien Jarno <aurelien@aurel32.net>

In terms of encoding MIPS32R6 MIN.fmt, MAX.fmt, MINA.fmt, MAXA.fmt replaced
MIPS-3D RECIP1, RECIP2, RSQRT1, RSQRT2 instructions.

In R6 all Floating Point instructions are supposed to be IEEE-2008 compliant
i.e. FIR.HAS2008 always 1. However, QEMU softfloat for MIPS has not been
updated yet.
Signed-off-by: NLeon Alrae <leon.alrae@imgtec.com>
Reviewed-by: NYongbok Kim <yongbok.kim@imgtec.com>

Signed-off-by: NLeon Alrae <leon.alrae@imgtec.com>
Reviewed-by: NYongbok Kim <yongbok.kim@imgtec.com>

Introduce MIPS32R6 Compact Branch instructions which do not have delay slot -
they have forbidden slot instead. However, current implementation does not
support forbidden slot yet.

Add also BC1EQZ and BC1NEZ instructions.
Signed-off-by: NYongbok Kim <yongbok.kim@imgtec.com>
Signed-off-by: NLeon Alrae <leon.alrae@imgtec.com>

Signed-off-by: NYongbok Kim <yongbok.kim@imgtec.com>
Signed-off-by: NLeon Alrae <leon.alrae@imgtec.com>
Reviewed-by: NAurelien Jarno <aurelien@aurel32.net>

In R6 the special behaviour for data references is also specified for Kernel
and Supervisor mode. Therefore MIPS_HFLAG_UX is replaced by generic
MIPS_HFLAG_AWRAP indicating enabled 32-bit address wrapping.
Signed-off-by: NLeon Alrae <leon.alrae@imgtec.com>
Reviewed-by: NAurelien Jarno <aurelien@aurel32.net>

Also consider OPC_SPIM instruction as deleted in R6 because it is overlaping
with MIPS32R6 SDBBP.
Signed-off-by: NLeon Alrae <leon.alrae@imgtec.com>
Reviewed-by: NAurelien Jarno <aurelien@aurel32.net>

Use "R6_" prefix in front of all new Multiply / Divide instructions for
easier differentiation between R6 and preR6.
Signed-off-by: NLeon Alrae <leon.alrae@imgtec.com>
Reviewed-by: NAurelien Jarno <aurelien@aurel32.net>

The encoding of PREF, CACHE, LLD and SCD instruction changed in MIPS32R6.
Additionally, the hint codes in PREF instruction greater than or
equal to 24 generate Reserved Instruction Exception.
Signed-off-by: NLeon Alrae <leon.alrae@imgtec.com>
Reviewed-by: NAurelien Jarno <aurelien@aurel32.net>

Move DSP and Loongson instruction to *_legacy functions as they have been
removed in R6.
Signed-off-by: NLeon Alrae <leon.alrae@imgtec.com>
Reviewed-by: NAurelien Jarno <aurelien@aurel32.net>

For better code readability and to avoid 'if' statements for all R6 and preR6
instructions whose opcodes are the same - decode_opc_special* functions are
split into functions with _r6 and _legacy suffixes.

*_r6 functions will contain instructions which were introduced in R6.
*_legacy functions will contain instructions which were removed in R6.
Signed-off-by: NLeon Alrae <leon.alrae@imgtec.com>
Reviewed-by: NAurelien Jarno <aurelien@aurel32.net>

Creating separate decode functions for special, special2 and special3
instructions to ease adding new R6 instructions and removing legacy
instructions.
Signed-off-by: NLeon Alrae <leon.alrae@imgtec.com>
Reviewed-by: NAurelien Jarno <aurelien@aurel32.net>

The encoding of LL and SC instruction has changed in MIPS32 Release 6.
Signed-off-by: NLeon Alrae <leon.alrae@imgtec.com>
Reviewed-by: NAurelien Jarno <aurelien@aurel32.net>
Reviewed-by: NJames Hogan <james.hogan@imgtec.com>

Signed-off-by: NLeon Alrae <leon.alrae@imgtec.com>
Reviewed-by: NAurelien Jarno <aurelien@aurel32.net>
Reviewed-by: NJames Hogan <james.hogan@imgtec.com>

Signal Reserved Instruction Exception on instructions that do not exist in R6.
In this commit the following groups of preR6 instructions are marked as deleted:
- Floating Point Paired Single
- Floating Point Compare
- conditional moves / branches on FPU conditions
- branch likelies
- unaligned loads / stores
- traps
- legacy accumulator instructions
- COP1X
- MIPS-3D
Signed-off-by: NLeon Alrae <leon.alrae@imgtec.com>
Reviewed-by: NAurelien Jarno <aurelien@aurel32.net>

Signed-off-by: NLluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Free t0 and t1 in opcode OPC_DINSV.
Signed-off-by: NDongxue Zhang <elta.era@gmail.com>
Signed-off-by: NAurelien Jarno <aurelien@aurel32.net>

The EBase CP0 register is initialised to 0x80000000, however with KVM
the guest's KSEG0 is at 0x40000000. The incorrect value doesn't get
passed to KVM yet as KVM doesn't implement the EBase register, however
we should set it correctly now so as not to break migration/loadvm to a
future version of QEMU that does support EBase.

Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
Reviewed-by: NAurelien Jarno <aurelien@aurel32.net>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

In order to avoid access to the CPUMIPSState structure in the
translator, keep a copy of CP0_Config1 into DisasContext. The whole
register is read-only so it can be copied as a single value.
Signed-off-by: NAurelien Jarno <aurelien@aurel32.net>

From MIPS documentation (Volume III):

UserLocal Register (CP0 Register 4, Select 2)
Compliance Level: Recommended.

The UserLocal register is a read-write register that is not interpreted by
the hardware and conditionally readable via the RDHWR instruction.

This register only exists if the Config3-ULRI register field is set.

Privileged software may write this register with arbitrary information and
make it accessible to unprivileged software via register 29 (ULR) of the
RDHWR instruction. To do so, bit 29 of the HWREna register must be set to a
1 to enable unprivileged access to the register.
Signed-off-by: NPetar Jovanovic <petar.jovanovic@imgtec.com>
Reviewed-by: NAndreas Färber <afaerber@suse.de>
Reviewed-by: NAurelien Jarno <aurelien@aurel32.net>
Signed-off-by: NAurelien Jarno <aurelien@aurel32.net>

The MIPS CPU timer (CP0 Count/Compare registers & QEMU timer) is
reset at machine initialisation, including starting the timeout. Both
registers however are placed before mvp in CPUMIPSState so they will
both be zeroed on reset by the memset in mips_cpu_reset() including soon
after init. This doesn't take into account that the timer may be
running, in which case env->CP0_Count will represent the delta against
the VM clock and the timeout will need updating.

At init time (cpu_mips_clock_init()), lets only create the timer.
Setting Count = 1 and starting the timer (cpu_mips_store_count()) can be
done at reset time from cpu_state_reset(), which is after the memset.
There is also no need to set CP0_Compare = 0 as that is already handled
by the memset.

Note that a reset occurs from mips_cpu_realizefn() which is before the
machine init callback has had a chance to set up the CPU interrupts and
the CPU timer, so env->timer will be NULL. This case is handled
explicitly in cpu_mips_store_count(), treating the timer as disabled
(which will also be the right thing to do when KVM support is added).
Reported-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NJames Hogan <james.hogan@imgtec.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This will collect all load and store helpers soon.  For now
it is just a replacement for softmmu_exec.h, which this patch
stops including directly, but we also include it where this will
be necessary in order to simplify the next patch.
Reviewed-by: NRichard Henderson <rth@twiddle.net>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Rather than include helper.h with N values of GEN_HELPER, include a
secondary file that sets up the macros to include helper.h.  This
minimizes the files that must be rebuilt when changing the macros
for file N.
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Signed-off-by: NRichard Henderson <rth@twiddle.net>

Previous implementation presumed that FPU registers are 64-bit and are
working in 64-bit mode. This change first checks MIPS_HFLAG_F64 and if not
set, it does load/store from the odd numbered register pair.
Patch by Matthew Fortune.
Signed-off-by: NMatthew Fortune <matthew.fortune@imgtec.com>
Signed-off-by: NPetar Jovanovic <petar.jovanovic@imgtec.com>
Signed-off-by: NAurelien Jarno <aurelien@aurel32.net>

Most targets were using offsetof(CPUFooState, breakpoints) to determine
how much of CPUFooState to clear on reset. Use the next field after
CPU_COMMON instead, if any, or sizeof(CPUFooState) otherwise.
Signed-off-by: NAndreas Färber <afaerber@suse.de>

Signed-off-by: NAndreas Färber <afaerber@suse.de>

Description of UFR feature:

Required in MIPS32r5 if floating point is implemented and user-mode FR
switching is supported. The UFR register allows user-mode to clear StatusFR
by executing a CTC1 to UFR with GPR[0] as input, and read StatusFR by
executing a CFC1 to UFR.

helper_ctc1 has been extended with an additional parameter rt to check
requirements for UFR feature.
Definition of mips32r5-generic has been modified to include support for UFR.
Signed-off-by: NPetar Jovanovic <petar.jovanovic@imgtec.com>
Reviewed-by: NEric Johnson <eric.johnson@imgtec.com>

Add CP0_Config5, define rw_bitmask and enable modifications.
Signed-off-by: NPetar Jovanovic <petar.jovanovic@imgtec.com>
Reviewed-by: NEric Johnson <eric.johnson@imgtec.com>

Add CP0_Config4, define rw_bitmask.
Signed-off-by: NPetar Jovanovic <petar.jovanovic@imgtec.com>
Reviewed-by: NEric Johnson <eric.johnson@imgtec.com>

Reviewed-by: NRichard Henderson <rth@twiddle.net>
Signed-off-by: NAurelien Jarno <aurelien@aurel32.net>

FR bit should be initialized to 1 for MIPS64, under condition that this
bit is writable and that CPU has an FPU unit. It should be initialized to
zero for MIPS32.
This fixes different MIPS32 issues with FPU instructions whose behaviour
defaulted to 64-bit FPU mode.
Signed-off-by: NPetar Jovanovic <petar.jovanovic@imgtec.com>
Signed-off-by: NAurelien Jarno <aurelien@aurel32.net>

No longer needs to be done on a per-target basis.
Signed-off-by: NRichard Henderson <rth@twiddle.net>

Since this is only read in cpu_copy() and linux-user has a global
cpu_model, drop the field from generic code.
Signed-off-by: NAndreas Färber <afaerber@suse.de>