Signed-off-by: NFrediano Ziglio <freddy77@gmail.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Gdb expects all registers windows to be flushed in ram, which is not the case
in Qemu. Therefore the back-trace generation doesn't work. This patch adds a
function to handle reads (and only read) in stack frames as if windows were
flushed.
Signed-off-by: NFabien Chouteau <chouteau@adacore.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

Add myself as target-xtensa and DC232B maintainer.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

This is Diamond 232L Standard Core Rev.B (LE).
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

See ISA, 4.3.9
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

- TLB opcode group;
- region protection option (ISA, 4.6.3);
- region translation option (ISA, 4.6.4);
- MMU option (ISA, 4.6.5).

Cache control attribute bits are not used by this implementation.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

Specific xtensa processor overlay for GDB contains register map in
the gdb/xtensa-config.c. This description is used by the GDB to e.g.
parse 'g' response packets and it may be reused in the qemu's gdbstub
(only XTREG definitions for non-pseudoregisters are needed).

Currently mainline GDB does not support operations with privileged SRs
(see http://sourceware.org/ml/gdb/2011-07/msg00075.html). This support
may be enabled, see NUM_CORE_REGS comment in the gdbstub.c
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

See ISA, 4.4.3 for details.

Vector addresses recorded in core configuration are absolute values that
correspond to default VECBASE value.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

See ISA, 4.7.1.3 for details.

Window check is inserted before commands that push "used register
watermark" beyond its current level. Used register watermark is reset on
instructions that change WINDOW_BASE/WINDOW_START SRs.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

See ISA, 4.4.6 (interrupt option), 4.4.7 (high priority interrupt
option) and 4.4.8 (timer interrupt option) for details.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

Tensilica iss provides support for applications running in freestanding
environment through SIMCALL command. It is used by Tensilica libc to
access argc/argv, for file I/O, etc.

Note that simcalls that accept buffer addresses expect virtual addresses.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

See ISA, 4.4.4 for details.

Correct (aligned as per ISA) address for unaligned access is generated
in case this option is not enabled.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

See ISA, 4.3.3 for details.

TB flag XTENSA_TBFLAG_LITBASE is used to track enable bit of LITBASE SR.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

See ISA, 4.3.2 for details.

Operations that change LEND SR value invalidate TBs at the old and at
the new LEND. LEND value at TB compilation time is considered constant
and loop instruction is generated based on this value.

Invalidation may be avoided for the TB at the old LEND address, since
looping code verifies actual LEND value.

Invalidation may be avoided for the TB at the new LEND address if
there's a way to associate LEND address with TB at compilation time and
later verify that it doesn't change.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

See ISA, 4.7.1 for details.

Physical registers and currently visible window are separate fields in
CPUEnv. Only current window is accessible to TCG. On operations that
change window base helpers copy current window to and from physical
registers.

Window overflow check described in 4.7.1.3 is in separate patch.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

- mark privileged opcodes with ring check;
- make debug exception on exception handler entry.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

All operations in this group are no-ops, because cache ought to be
transparent to applications. However cache may be abused, then we'll
need to actually implement these opcodes.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

All operations in this group are no-ops, because there are no delayed
side effects.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

Reserved opcodes must generate illegal instruction exception. Usually
they signal emulation quality problems.
Not implemented opcodes are good to see.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

- base + offset load/store operations for 1/2/4 byte values;
- cache operations (not implemented);
- multiprocessor synchronization operations.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

- ST1: SAR (shift amount special register) manipulation, NSA(U);
- RST1: shifts, 16-bit multiplication.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

- access to Special Registers (wsr, rsr);
- access to User Registers (wur, rur);
- misc. operations option (value clamp, sign extension, min, max);
- conditional moves.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

Special Registers hold the majority of the state added to the processor
by the options. See ISA, 5.3 for details.

User Registers hold state added in support of designer's TIE and in some
cases of options that Tensilica provides. See ISA, 5.4 for details.

Only registers mapped in sregnames or uregnames are considered valid.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

Group SNM0 (indirect jumps and calls).
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

- BZ (comparison to zero);
- BI0 (comparison to signed immediate);
- BI1 (comparison to unsigned immediate);
- B (two registers comparison, bit sets comparison);
- BEQZ.N/BNEZ.N (narrow comparison to zero).
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

Sample board and sample CPU core are used for debug and may be used for
development of custom SoC emulators.

This board has two fixed size memory regions for DTCM and ITCM and
variable length SRAM region.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

NEG and ABS are the only members of RT0 group.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

Instructions with op0 >= 8 are 2 bytes long, others are 3 bytes long.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

Set up disas_xtensa_insn switch structure, mark required options on high
level groups. Implement arithmetic/bit logic/jump/call0.

Implement code generation loop with single step/breakpoint checking.
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

Signed-off-by: NHervé Poussineau <hpoussin@reactos.org>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

Move mipsnet_init() function to mipssim machine
Signed-off-by: NHervé Poussineau <hpoussin@reactos.org>
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

Remove a useless variable, spotted by clang analyzer:
/src/qemu/target-sparc/op_helper.c:3904:18: warning: unused variable 'tmp' [-Wunused-variable]
    target_ulong tmp = val;
The error message is actually incorrect since the variable is used.
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>

Avoid this warning from clang analyzer by deleting the variable:
/src/qemu/hw/lsi53c895a.c:895:5: warning: Value stored to 'id' is never read
    id = (current_tag >> 8) & 0xf;
Signed-off-by: NBlue Swirl <blauwirbel@gmail.com>