Add prefix, suffix, operation descriptions, and other corrections
and amendments to the comment that describes MXU ASE.
Backports commit 093ade12179b6a3f679c100c0fe2a0a7d72068ba from qemu
Move MUL, S32M2I, S32I2M handling out of switch. These are all
instructions that do not depend on MXU_EN flag of MXU_CR.
Backports commit 87860df5511b972f0234a6b2cfaad5227c79b6b4 from qemu
Add support for emulating the S32I2M and S32M2I MXU instructions.
This commit also contains utility functions for reading/writing
to MXU registers. This is required for overall MXU instruction
support.
Backports commit 96992d1aa1b250c0fffc1ff2dad5e6e4f0b9815b from qemu
Add MXU decoding engine: add handlers for all instruction pools,
and main decode handler. The handlers, for now, for the purpose
of this patch, contain only sceleton in the form of a single
switch statement.
Backports commit 03f400883a1dd92fac5b0d9127b38e34c9a722d7 from qemu
Amend MXU instruction opcodes. Pool04 is actually only instruction
OPC_MXU_S16MAD. Two cases within S16MAD are recognized by 1-bit
subfield 'aptn1'.
Backports commit eab0bdb07cbed1131be2d1f541059c7b96b05e32 from qemu
Define a bit for MXU in insn_flags. This is the first non-MIPS
(third party) ASE supported in QEMU for MIPS, so it is placed in
the section "bits 56-63: vendor-specific ASEs".
Backports commit a031ac61619294ae473a78d1834e757fad8b59e5 from qemu
Define and initialize the 16 MXU registers - 15 general computational
register, and 1 control register). There is also a zero register, but
it does not have any corresponding variable.
Backports commit eb5559f67dc8dc12335dd996877bb6daaea32eb2 from qemu.
Implement emulation of nanoMIPS EVA instructions. They are all
part of P.LS.E0 instruction pool, or one of its subpools.
Backports commit d046a9ea1b8877a570a8b12a2d0125ec59fe5b22 from qemu
Opcode for ALIGN and DALIGN must be in fact ranges of opcodes, to
allow paremeter 'bp' to occupy two and three bits, respectively.
Backports commit 373ecd3823f949fd550ec49685299e287af5753e from qemu
Replace MIPS32 with MIPS, since the file covers all generations
of MIPS architectures.
Backports commit ab99e0e44bc7b0e2e52d9083a673866b18470536 from qemu
The primary purpose of this change is to support programs compiled by
GCC for the R5900 target and thereby run R5900 Linux distributions, for
example Gentoo.
GCC in version 7.3, by itself, by inspection of the GCC source code
and inspection of the generated machine code, for the R5900 target,
only emits two instructions that are specific to the R5900: the three-
operand MULT and MULTU. GCC and libc also emit certain MIPS III
instructions that are not part of the R5900 ISA. They are normally
trapped and emulated by the Linux kernel, and therefore need to be
treated accordingly by QEMU.
A program compiled by GCC is taken to mean source code compiled by GCC
under the restrictions above. One can, with the apparent limitations,
with a bit of effort obtain a fully functioning operating system such
as R5900 Gentoo. Strictly speaking, programs need not be compiled by
GCC to make use of this change.
Instructions and other facilities of the R5900 not implemented by this
change are intended to signal provisional exceptions. One such example
is the FPU that is not compliant with IEEE 754-1985 in system mode. It
is therefore provisionally disabled. In user space the FPU is trapped
and emulated by IEEE 754-1985 compliant software in the kernel, and
this is handled accordingly by QEMU. Another example is the 93
multimedia instructions specific to the R5900 that generate provisional
reserved instruction exception signals.
One of the benefits of running a Linux distribution under QEMU is that
programs can be compiled with a native compiler, where the host and
target are the same, as opposed to a cross-compiler, where they are
not the same. This is especially important in cases where the target
hardware does not have the resources to run a native compiler.
Problems with cross-compilation are often related to host and target
differences in integer sizes, pointer sizes, endianness, machine code,
ABI, etc. Sometimes cross-compilation is not even supported by the
build script for a given package. One effective way to avoid those
problems is to replace the cross-compiler with a native compiler. This
change of compilation methods does not resolve the inherent problems
with cross-compilation.
The native compiler naturally replaces the cross-compiler, because one
typically uses one or the other, and preferably the native compiler
when the circumstances admit this. The native compiler is also a good
test case for the R5900 QEMU user mode. Additionally, Gentoo is well-
known for compiling and installing its packages from sources.
This change has been tested with Gentoo compiled for R5900, including
native compilation of several packages under QEMU.
Backports commit ed4f49ba9bb56ebca6987b1083255daf6c89b5de from qemu.
The Linux kernel traps certain reserved instruction exceptions to
emulate the corresponding instructions. QEMU plays the role of the
kernel in user mode, so those traps are emulated by accepting the
instructions.
This change adds the function check_insn_opc_user_only to signal a
reserved instruction exception for flagged CPUs in QEMU system mode.
The MIPS III instructions DMULT[U], DDIV[U], LL[D] and SC[D] are not
implemented in R5900 hardware. They are trapped and emulated by the
Linux kernel and, accordingly, therefore QEMU user only instructions.
Backports commit 96631327be14c4f54cc31f873c278d9ffedd1e00 from qemu
The R5900 is taken to be MIPS III with certain modifications. From
MIPS IV it implements the instructions MOVN, MOVZ and PREF.
Backports commit 5601e6217d90ed322b4b9a6d68e8db607db91842 from qemu
The three-operand MULT and MULTU are the only R5900-specific
instructions emitted by GCC 7.3. The R5900 also implements the three-
operand MADD and MADDU instructions, but they are omitted in QEMU for
now since they are absent in programs compiled by current GCC versions.
Likewise, the R5900-specific pipeline 1 instruction variants MULT1,
MULTU1, DIV1, DIVU1, MADD1, MADDU1, MFHI1, MFLO1, MTHI1 and MTLO1
are omitted here as well.
Backports commit 21e8e8b230af38b6bd8c953fa5f31e4a5a128e1c from qemu
The R5900 implements the 64-bit MIPS III instruction set except
DMULT, DMULTU, DDIV, DDIVU, LL, SC, LLD and SCD. The MIPS IV
instructions MOVN, MOVZ and PREF are implemented. It has the
R5900-specific three-operand instructions MADD, MADDU, MULT and
MULTU as well as pipeline 1 versions MULT1, MULTU1, DIV1, DIVU1,
MADD1, MADDU1, MFHI1, MFLO1, MTHI1 and MTLO1. A set of 93 128-bit
multimedia instructions specific to the R5900 is also implemented.
The Toshiba TX System RISC TX79 Core Architecture manual:
https://wiki.qemu.org/File:C790.pdf
describes the C790 processor that is a follow-up to the R5900. There
are a few notable differences in that the R5900 FPU
- is not IEEE 754-1985 compliant,
- does not implement double format, and
- its machine code is nonstandard.
Backports commit 6f692818a7b53630702d25a709cd61282fd139ad from qemu
Fix misplaced 'break' in handling of NM_SHRA_R_PH. Found by
Coverity (CID 1395627).
Backports commit d5ebcbaf09e8c14e62b2966446195be5eeabcbab from qemu
Fix emulation of microMIPS R6 <SELEQZ|SELNEZ>.<D|S> instructions.
Their handling was permuted.
Backports commit fdac60cd0458f34b2e79d74a55bec10836e26471 from qemu
Implement hardware page table walker. This implementation is
limiter only to MIPS32.
Backports commit 074cfcb4daedf59ccbbbc83c24eee80e0e8f4c71 from qemu
Add reset state for PWSize and PWField registers. The reset state
is different for pre-R6 and R6 (and post-R6) ISAa
Backports commit 630107955757b9dfc5c09f105caa267eded2e3b1 from qemu
Add PWCtl register (CP0 Register 5, Select 6).
The PWCtl register configures hardware page table walking for TLB
refills.
This register is required for the hardware page walker feature. It
exists only if Config3 PW bit is set to 1. It contains following
fields:
PWEn (31) - Hardware Page Table walker enable
PWDirExt (30) - If 1, 4-th level implemented (MIPS64 only)
XK (28) - If 1, walker handles xkseg (MIPS64 only)
XS (27) - If 1, walker handles xsseg (MIPS64 only)
XU (26) - If 1, walker handles xuseg (MIPS64 only)
DPH (7) - Dual Page format of Huge Page support
HugePg (6) - Huge Page PTE supported in Directory levels
PSn (5..0) - Bit position of PTEvld in Huge Page PTE
Backports commit 103be64c26c166f12b3e1308edadef3443723ff1 from qemu
Add PWSize register (CP0 Register 5, Select 7).
The PWSize register configures hardware page table walking for TLB
refills.
This register is required for the hardware page walker feature. It
exists only if Config3 PW bit is set to 1. It contains following
fields:
BDW (37..32) Base Directory index width (MIPS64 only)
GDW (29..24) Global Directory index width
UDW (23..18) Upper Directory index width
MDW (17..12) Middle Directory index width
PTW (11..6 ) Page Table index width
PTEW ( 5..0 ) Left shift applied to the Page Table index
Backports commit 20b28ebc49945583d7191b57755cfd92433de9ff from qemu
Add PWField register (CP0 Register 5, Select 6).
The PWField register configures hardware page table walking for TLB
refills.
This register is required for the hardware page walker feature. It
exists only if Config3 PW bit is set to 1. It contains following
fields:
MIPS64:
BDI (37..32) - Base Directory index
GDI (29..24) - Global Directory index
UDI (23..18) - Upper Directory index
MDI (17..12) - Middle Directory index
PTI (11..6 ) - Page Table index
PTEI ( 5..0 ) - Page Table Entry shift
MIPS32:
GDW (29..24) - Global Directory index
UDW (23..18) - Upper Directory index
MDW (17..12) - Middle Directory index
PTW (11..6 ) - Page Table index
PTEW ( 5..0 ) - Page Table Entry shift
Backports commit fa75ad1459f4f6abbeb6d375a812dfad61320f58 from qemu
