MIPS Release 6 and MIPS SIMD Architecture make it mandatory to have IEEE
754-2008 FPU which is indicated by CP1 FIR.HAS2008, FCSR.ABS2008 and
FCSR.NAN2008 bits set to 1.
In QEMU we still keep these bits cleared as there is no 2008-NaN support.
However, this now causes problems preventing from running R6 Linux with
the v4.5 kernel. Kernel refuses to execute 2008-NaN ELFs on a CPU
whose FPU does not support 2008-NaN encoding:
(...)
VFS: Mounted root (ext4 filesystem) readonly on device 8:0.
devtmpfs: mounted
Freeing unused kernel memory: 256K (ffffffff806f0000 - ffffffff80730000)
request_module: runaway loop modprobe binfmt-464c
Starting init: /sbin/init exists but couldn't execute it (error -8)
request_module: runaway loop modprobe binfmt-464c
Starting init: /bin/sh exists but couldn't execute it (error -8)
Kernel panic - not syncing: No working init found. Try passing init= option to kernel. See Linux Documentation/init.txt for guidance.
Therefore always indicate presence of 2008-NaN support in R6 as well as in
R5+MSA CPUs, even though this feature is not yet supported by MIPS in QEMU.
Backports commit ba5c79f26221c0fd7139c883a34a4e75d993f732 from qemu
The MAAR register is a read/write register included in Release 5
of the architecture that defines the accessibility attributes of
physical address regions. In particular, MAAR defines whether an
instruction fetch or data load can speculatively access a memory
region within the physical address bounds specified by MAAR.
As QEMU doesn't do speculative access, hence this patch only
provides ability to access the registers.
Backports commit f6d4dd810983fdf3d1c9fb81838167efef63d1c8 from qemu
Physical base address for the memory-mapped Coherency Manager Global
Configuration Register space.
The MIPS default location for the GCR_BASE address is 0x1FBF_8.
This register only exists if Config3 CMGCR is set to one.
Backports commit c870e3f52cac0c8a4a1377398327c4ff20d49d41 from qemu
MIPS Release 6 provides multi-threading features which replace
pre-R6 MT Module. CP0.Config3.MT is always 0 in R6, instead there is new
CP0.Config5.VP (Virtual Processor) bit which indicates presence of
multi-threading support which includes CP0.GlobalNumber register and
DVP/EVP instructions.
Backports commit 01bc435b44b8802cc4697faa07d908684afbce4e from qemu
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.
This commit was created with scripts/clean-includes.
Backports commit c684822ad29968af09735148f03a511bc514589d from qemu
If executing ALIGN with shift count bp=0 within mips64 emulation,
the result of the operation should be sign extended.
Taken from the official documentation (pseudo code) :
ALIGN:
tmp_rt_hi = unsigned_word(GPR[rt]) << (8*bp)
tmp_rs_lo = unsigned_word(GPR[rs]) >> (8*(4-bp))
tmp = tmp_rt_hi || tmp_rt_lo
GPR[rd] = sign_extend.32(tmp)
Backports commit 51243852af322f0a1103a90c936c43db84def82f from qemu
Add SIGRIE (Signal Reserved Instruction Exception) for both MIPS and
microMIPS.
The instruction allows to use the 16-bit code field for software use.
This instruction is introduced by and required as of Release 6.
Backports commit bb238210bb096534b68dab15a87c6ff0bef43672 from qemu
Add Performance Counter (4) and XNP (5) register numbers to RDHWR.
Add check_hwrena() to simplify access control checkings.
Add RDHWR support to microMIPS R6.
Backports commit b00c72180c36510bf9b124e190bd520e3b7e1358 from qemu
Some targets already had this within their logic, but make sure
it's present for all targets.
Backports commit 522a0d4e3c0d397ffb45ec400d8cbd426dad9d17 from qemu
Reduce the boilerplate required for each target. At the same time,
move the test for breakpoint after calling tcg_gen_insn_start.
Note that arm and aarch64 do not use cpu_breakpoint_test, but still
move the inline test down after tcg_gen_insn_start.
Backports commit b933066ae03d924a92b2616b4a24e7d91cd5b841 from qemu
It is no longer used, so tidy up everything reached by it.
This includes the gen_opc_* arrays, the search_pc parameter
and the inline gen_intermediate_code_internal functions.
Backports commit 4e5e1215156662b2b153255c49d4640d82c5568b from qemu
The gen_opc_* arrays are already redundant with the data stored in
the insn_start arguments. Transition restore_state_to_opc to use
data from the latter.
Backports commit bad729e272387de7dbfa3ec4319036552fc6c107 from qemu
This patch improves exception handling in MIPS.
Instructions generate several types of exceptions.
When exception is generated, it breaks the execution of the current
translation block. Implementation of the exceptions handling does not
correctly restore icount for the instruction which caused the exception.
In most cases icount will be decreased by the value equal to the size of
TB. This patch passes pointer to the translation block internals to the
exception handler. It allows correct restoring of the icount value.
Backports commit 9c708c7f9fbb813a3fac02f2728e51e62f2f5ffc from qemu
rs cannot be the zero register, Reserved Instruction exception must be
signalled for this case.
Backports commit db77d8523909b32d798cd2c80de422b68f9e5c42 from qemu
MIPS_DEBUG is a define used to dump the instruction disassembling. It
has to be defined at compile time. In practice I believe it's more
efficient to just look at the instruction disassembly and op dump using
-d in_asm,op. This patch therefore removes the corresponding code, which
clutters translate.c.
Backports commit 9d68ac14dab3f5af33a6b23458941dc6fb261fce from qemu
MIPS_DEBUG_SIGN_EXTENSIONS was used sometimes ago to verify that 32-bit
instructions correctly sign extend their results. It's now not need
anymore, remove it.
Backports commit b307446e04232b3a87e9da04886895a8e5a4a407 from qemu
Instructions recip.{s|d} and rsqrt.{s|d} do not require 64-bit FPU neither
they require any particular mode for its FPU. This patch removes the checks
that may break a program that uses these instructions.
Backports commit ca6c7803d2beae43299a80f4549d36579881fc0b from qemu
The LWL/LDL instructions mask the GPR with a mask depending on the
address alignement. It is currently computed by doing:
mask = 0x7fffffffffffffffull >> (t1 ^ 63)
It's simpler to generate it by doing:
mask = ~(-1 << t1)
It uses one TCG instruction less, and it avoids a 32/64-bit constant
loading which can take a few instructions on RISC hosts.
Backports commit eb02cc3f89013612cb05df23b5441741e902bbd2 from qemu
In semihosting mode the SDBBP 1 instructions should trigger UHI syscall,
but in QEMU this does not happen for recently added microMIPS R6.
Consequently bare metal microMIPS R6 programs supporting UHI will not run.
Backports commit 060ebfef1a09b58fb219b3769b72efb407515bf1 from qemu
When a LWL, LWR, LDL or LDR instruction triggers a page fault, QEMU
currently reports the aligned address in CP0 BadVAddr, while the Windows
NT kernel expects the unaligned address.
This patch adds a byte access with the unaligned address at the
beginning of the LWL/LWR/LDL/LDR instructions to possibly trigger a page
fault and fill the QEMU TLB.
Backports commit 908680c6441ac468f4871d513f42be396ea0d264 from qemu
Signal a Reserved Instruction exception for removed instruction encoding
in microMIPS Release 6.
Backports commit 9e8f441a7e094c0dc33a1c8f521d9e5bcfc1b4da from qemu
64-bit paired-single (PS) floating point data type is optional in the
pre-Release 6.
It has to raise RI exception when PS type is not implemented. (FIR.PS = 0)
(The PS data type is removed in the Release 6.)
Loongson-2E and Loongson-2F don't have any implementation field in
FCSR0(FIR) but do support PS data format, therefore for these cores RI will
not be signalled regardless of PS bit.
Backports commit e29c962804c4dd3fabd44e703aa87eec555ed910 from qemu
Refactor those instructions in order to reuse them for microMIPS32
Release 6.
Rearrange gen_move_low32().
Backports commit 1f1b4c008e250f870719ed38fbd0bcc14322fc01 from qemu
Implement MTHC0 and MFHC0 instructions. In MIPS32 they are used to access
upper word of extended to 64-bits CP0 registers.
In MIPS64, when CP0 destination register specified is the EntryLo0 or
EntryLo1, bits 1:0 of the GPR appear at bits 31:30 of EntryLo0 or
EntryLo1. This is to compensate for RI and XI, which were shifted to bits
63:62 by MTC0 to EntryLo0 or EntryLo1. Therefore creating separate
functions for EntryLo0 and EntryLo1.
Backports commit 5204ea79ea739b557f47fc4db96c94edcb33a5d6 from qemu
CP0.PageGrain.ELPA enables support for large physical addresses. This field
is encoded as follows:
0: Large physical address support is disabled.
1: Large physical address support is enabled.
If this bit is a 1, the following changes occur to coprocessor 0 registers:
- The PFNX field of the EntryLo0 and EntryLo1 registers is writable and
concatenated with the PFN field to form the full page frame number.
- Access to optional COP0 registers with PA extension, LLAddr, TagLo is
defined.
P5600 can operate in 32-bit or 40-bit Physical Address Mode. Therefore if
XPA is disabled (CP0.PageGrain.ELPA = 0) then assume 32-bit Address Mode.
In MIPS64 assume 36 as default PABITS (when CP0.PageGrain.ELPA = 0).
env->PABITS value is constant and indicates maximum PABITS available on
a core, whereas env->PAMask is calculated from env->PABITS and is also
affected by CP0.PageGrain.ELPA.
Backports commit e117f52636d04502fab28bd3abe93347c29f39a5 from qemu
Extend EntryLo0, EntryLo1, LLAddr and TagLo from 32 to 64 bits in MIPS32.
Introduce gen_move_low32() function which moves low 32 bits from 64-bit
temp to GPR; it sign extends 32-bit value on MIPS64 and truncates on
MIPS32.
Backports commit 284b731a6ae47b9ebabb9613e753c4d83cf75dd3 from qemu
