StoreThrough in VIPER when the TCP is disabled, GLC bit is set, or SLC
bit is set will bypass the TCP, but will temporarily allocate a cache
entry seemingly to handle write coalescing with valid blocks. It does
not attempt to evict a block if the set is full and the address is
invalid. This causes a panic if the set is full as there is no spare
cache entry to use temporarily to use for DataBlk manipulation. However,
a cache block is not required for this.
This commit removes using a cache block for StoreThrough with invalid
blocks as there is no existing data to coalesce with. It creates no
allocate variants of the actions needed in StoreThrough and pulls the
DataBlk information from the in_msg instead. Non-invalid blocks do not
have this panic as they have a cache entry already.
Fixes issues with StoreThroughs on more aggressive architectures like
MI300.
Change-Id: Id8687eccb991e967bb5292068cbe7686e0930d7d
Those AArch64 instructions/registers were labelled as executable
from EL3 only if SCR_EL3.NS == 1. This is not valid anymore
after the introduction of FEAT_SEL2
The new static analysis in GCC 13 finds issues with operand.hh. This
commit fixes the error so that gem5 compiles when BUILD_GPU is true.
Change-Id: I6f4b0d350f0cabb6e356de20a46e1ca65fd0da55
Those AArch64 instructions/registers were labelled as executable
from EL3 only if SCR_EL3.NS == 1. This is not valid anymore
after the introduction of FEAT_SEL2
Change-Id: Ie7b56f3fe779c3a99d4f0ef937c7c8ec0530b00e
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
This is making it easier for TLBI instructions to share code. Common
code (under the form of tlbi* functions) are closely matching the
instruction description in the Arm pseudocode
Change-Id: If10c22fb4a7df2bcd0335e9761286ad3c458722b
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
The bit 0 of register should be 0 for jump address. Wrong handling the
jump address may cause infinite run or segment fault.
gem5 issue: https://github.com/gem5/gem5/issues/981
Fixed the issue that did not allow building TLM.
Build commands:
```bash
scons build/ARM/gem5.opt
scons setconfig build/ARM USE_SYSTEMC=n
scons --with-cxx-config --without-python --without-tcmalloc build/ARM/libgem5_opt.so
cd util/tlm
scons
```
Following this README, I tested it successfully with the simple examples:
https://gem5.googlesource.com/public/gem5/+/master/util/tlm/README
GitHub Issue: #591
Change-Id: If07fae2eb20ad62627e733573f61bc42d594f970
---------
Co-authored-by: Ivana Mitrovic <ivanamit91@gmail.com>
note: Due to #556 / #555, we don't support GCC 9. This PR removes gcc-8
which means gem5 would support GCC >= version 10.
The reason for removing gcc-8:
1. We already dropped support for gcc-9. I don't see any good reason to
support anything <9 as a result.
2. GCC is relatively old, and we're probably supporting a bit too many
compiler versions anyway. In Ubuntu 22.04, gcc-11 is downloaded by
default with `apt`. It doesn't seem many system are still using gcc.
3. There is a weird compiler bug in gcc-8 which is causes failure when
compiling gem5 since the inclusion of #1123. The error received is as
follows:
```sh
In file included from src/arch/riscv/tlb.hh:42,
from src/arch/riscv/mmu.hh:45,
from build/ALL/arch/riscv/generated/exec-g.cc.inc:14,
from build/ALL/arch/riscv/generated/generic_cpu_exec.cc:5:
src/arch/riscv/utility.hh: In instantiation of ‘FloatType gem5::RiscvISA::ftype(IntType) [with FloatType = float8_t; IntType = unsigned char]’:
build/ALL/arch/riscv/generated/exec-ns.cc.inc:38839:42: required from ‘gem5::Fault gem5::RiscvISAInst::Vfwcvt_xu_f_vMicro<ElemType>::execute(gem5::ExecContext*, gem5::trace::InstRecord*) const [with ElemType = float8_t; gem5::Fault = std::shared_ptr<gem5::FaultBase>]’
build/ALL/arch/riscv/generated/exec-ns.cc.inc:38856:16: required from here
src/arch/riscv/utility.hh:327:15: error: parameter ‘a’ set but not used [-Werror=unused-but-set-parameter]
ftype(IntType a) -> FloatType
~~~~~~~~^
src/arch/riscv/utility.hh: In instantiation of ‘IntType gem5::RiscvISA::f_to_wui(FloatType, uint_fast8_t) [with FloatType = float8_t; IntType = short unsigned int; uint_fast8_t = unsigned char]’:
build/ALL/arch/riscv/generated/exec-ns.cc.inc:38838:49: required from ‘gem5::Fault gem5::RiscvISAInst::Vfwcvt_xu_f_vMicro<ElemType>::execute(gem5::ExecContext*, gem5::trace::InstRecord*) const [with ElemType = float8_t; gem5::Fault = std::shared_ptr<gem5::FaultBase>]’
build/ALL/arch/riscv/generated/exec-ns.cc.inc:38856:16: required from here
src/arch/riscv/utility.hh:570:20: error: parameter ‘a’ set but not used [-Werror=unused-but-set-parameter]
f_to_wui(FloatType a, uint_fast8_t mode)
```
Note: This is currently causing our SST Daily tests to fail, and our
compiler tests to fail.
This change fixes#1148
I have only added an acknowledged return, as we dont ahve remote and
wrap mode so it can only be in stream mode.
Change-Id: I1882042d873ff0e9465c9491238554c8fbb9aa76
Those were not part of the performTlbi switch and simulation was
therefore panicking when they were encountered
Change-Id: Ifbe0b89e45539df4abc147ac5970b0caf0d9dfdc
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
This commit fixes and refactors the implementation of viota. It also
overrides the generateDisassembly function in viota's macro/micro to
correctly print out the instruction when tacing/debugging.
For example, it changes from:
viota_m vd, vd, vs2, v0.t
to:
viota_m vd, vs2, v0.t
This adds two failsafes which may cause a panic on some machines. First,
check the host machine has the KVM XCR capability before calling getXCRs
or setXCRs. Second, ensure the x87 bit, which must always be one, will
always return at least one by modifying the return value in readMiscReg.
Change-Id: I5e778acc926a47443ef6cef29fabd84eb69bb9ba
This implements some missing loads and store that are commonly used in
applications with MFMA instructions to load 16-bit data types into
specific register locations: DS_READ_U16_D16, DS_READ_U16_D16_HI,
BUFFER_LOAD_SHORT_D16, BUFFER_LOAD_SHORT_D16_HI.
Change-Id: Ie22d81ef010328f4541553a9a674764dc16a9f4d
Add a unit test for the MXFP types (bf16, fp16, fp8, bf8). These types
are not currently operated on directly. Instead the are cast to float
values and then arithmetic is performed. As a result, the unit test
simply checks that when we convert a value from MXFP type to float and
back that the values of the MXFP type match. Exact values are used to
avoid discrepancies with rounding.
Can be run using scons build/VEGA_X86/unittests.opt .
Change-Id: I596e9368eb929d239dd2d917e3abd7927b15b71e
These instructions are used in some of the F16 MFMA example applications
to convert to/from floating point types.
Change-Id: I7426ea663ce11a39fe8c60c8006d8cca11cfaf07
This instruction is new in MI300 and is used in some of the example
applications used to test MFMAs.
Change-Id: I739f8ab2be6a93ee3b6bdc4120d0117724edb0d4
This adds the decodings for all of the matrix fused multiply add (MFMA)
and sparse matrix fused multiply accumulate (SMFMAC) instructions up to
and including MI300. This does not yet provide the implementation for
these instructions, however it is easier and less tedious to add them in
bulk rather that one at a time.
Change-Id: I5acd23ca8a26bdec843bead545d1f8820ad95b41
The microscaling formats (MXFP) and INT8 types require additional size
checks which are not needed for the current MFMA template. The size
check is done using a constexpr method exclusive to the MXFP type,
therefore create a special class for MXFP types. This is preferrable to
attempting to shoehorn into the existing template as it helps with
readability. Similar, INT8 requires a size check to determine number of
elements per VGPR, but it not an MXFP type. Create a special template
for that as well.
This additionally implements all of the MFMA types which have test cases
in the amd-lab-notes repository (https://github.com/amd/amd-lab-notes/).
The implementations were tested using the applications in the
matrix-cores subfolder and achieve L2 norms equivalent or better than
MI200 hardware.
Change-Id: Ia5ae89387149928905e7bcd25302ed3d1df6af38
This class can be used to load multiple operand dwords into an array and
then select bits from the span of that array. It handles cases where the
bits span two dwords (e.g., you have four dwords for a 128-bit value and
want to select bits 35:30) and cases where multiple values < 32-bits are
packed into a single dword (e.g., two bf16 values).
This is most useful for packed arrays and instructions which have more
than two dwords. Beyond two dwords, the operator[] overload of
VectorOperand is not available requiring additional logic to select from
an operand. This helper class handles that additional logic itself.
Change-Id: I74856d0f312f7549b3b6c405ab71eb2b174c70ac
The open compute project (OCP) microscaling formats (MX) are used in the
GPU model. The specification is available at [1]. This implements a C++
version of MXFP formats with many constraints that conform to the
specification.
Actually arithmetic is not performed directly on the MXFP types. They
are rather converted to fp32 and the computation is performed. For most
of these types this is acceptable for the GPU model as there are no
instruction which directly perform arithmetic on them. For example, the
DOT/MFMA instructions operating may first convert to FP32 and then
perform arithmetic.
Change-Id: I7235722627f7f66c291792b5dbf9e3ea2f67883e
Release of MI300X simulation capability:
- Implements the required MI300X features over MI200 (currently only
architecture flat scratch).
- Make the gpu-compute model use MI200 features when MI300X / gfx942 is
configured.
- Fix up the scratch_ instructions which are seem to be preferred in
debug hipcc builds over buffer_.
- Add mi300.py config similar to mi200.py. This config can optionally
use resources instead of command line args.
It appears we have been trying to read 64-bit arguments for ARM32 since
695583709b. I noticed that SYS_OPEN was
trying to read a really long string as the pathname argument and it
turned out it was reading from the wrong stack offset. With this change
I can successfully run some of the semihosting tests for ARM32.
Change-Id: Ie154052dac4211993fb6c4c99d93990123c2eacf
In BaseSemihosting::readString() we were using the len argument to
allocate a std::vector without checking whether the value makes any
sense. This resulted in a std::bad_alloc exception being raised prior to
https://github.com/gem5/gem5/pull/1142 for my semihosting tests. This
commit prevents semihosting from reading more than 64K for string
arguments which should be more than sufficient for any valid code.
Change-Id: I059669016ee2c5721fedb914595d0494f6cfd4cd
This commit fixes the implementation of vrgather instruction based on
rvv 1.0.
In section 16.4. Vector Register Gather Instructions,
> Vector-scalar and vector-immediate forms of the register gather are
also provided. These read one element from the source vector at the
given index, and write this value to the active elements of the
destination vector register. The index value in the scalar register and
the immediate, zero-extended to XLEN bits, are treated as unsigned
integers. If XLEN > SEW, the index value is not truncated to SEW bits.
The fix zero-extends the index value in the scalar register and the
immediate.
Add a config capable of simulating MI300X ISA (gfx942). This is similar
to the mi200.py config and uses the same scripts followed by some
tuneable parameters. This config optionally lets the user call the
runMI300GPU function with gem5 resources. This allows for something like
the following before a VIPER stdlib python is available:
```
import mi300
from gem5.resources.resource import obtain_resource
disk = obtain_resource("x86-gpu-fs-img")
kernel = obtain_resource("x86-linux-kernel-5.4.0-105-generic")
app = obtain_resource("square-gpu-test")
mi300.runMI300GPUFS("X86KvmCPU", disk, kernel, app)
```
Tested cold boot config, checkpoint create and restore, and using gem5
resources.
Change-Id: I50a13d7a3d207786b779bf7fd47a5645256b1e6a
Architected flat scratch is added in MI300 which store the scratch base
address in dedicated registers rather than in SGPRs. These registers are
used by scratch_ instructions. These are flat instruction which
explicitly target the private memory aperture. These instructions have a
different address calculation than global_ instructions.
This change implements architected flat scratch support, fixes the
address calculation of scratch_ instructions, and implements decodings
for some scratch_ instructions. Previous flat_ instructions which happen
to access the private memory aperture have no change in address
calculation. Since scratch_ instructions are identical to flat_
instruction except for address calculation, the decodings simply reuse
existing flat_ instruction definitions.
Change-Id: I1e1d15a2fbcc7a4a678157c35608f4f22b359e21
Add support for the following two extensions:
[Zvfh](https://github.com/riscv/riscv-v-spec/blob/master/v-spec.adoc#185-zvfh-vector-extension-for-half-precision-floating-point):
Vector Extension for Half-Precision Floating-Point
[Zvfhmin](https://github.com/riscv/riscv-v-spec/blob/master/v-spec.adoc#184-zvfhmin-vector-extension-for-minimal-half-precision-floating-point):
Vector Extension for Minimal Half-Precision Floating-Point
For instructions (`vfncvt[.rtz].x[u].f.w`) and (`vfwcvt.f.x[u].v`) which
will become defined when `SEW = 8`, a new template
`VectorFloatWideningAndNarrowingCvtDecodeBlock` is added and 8-bit
floating point type (`float8_t`) is defined.
The data type `float8_t` is introduced in the newer `3e` version of the
SoftFloat Package, however, the current version in use is `3d` which
does not include this definition. Despite this, `float8_t` is utilized
solely for constructing the `vfncvt[.rtz].x[u].f.w` and
`vfwcvt.f.x[u].v` instructions when `SEW = 8`. There are no operations
that directly manipulate data of the `float8_t` type.
This is the version for MI300. For the most part, it is the same as
MI200 with the exception of architected flat scratch (not yet
implemented in gem5) and therefore a new version enum is required.
Change-Id: Id18cd7b57c4eebd467c010a3f61e3117beb8d58a
- Adding this line as not specifiying GNU non executable stack was
throwing warnings when building m5
for ubuntu 24.04
Change-Id: I620c508be4090804698391cff671ba5091b053d7
These changes to sweep and sweep_hybrid for NVM allow them to run. I'm
not an expert on this, so I'm not sure if these are technically correct,
but they no longer fail when running
`build/X86/gem5.opt configs/nvm/sweep.py` and `build/X86/gem5.opt
configs/nvm/sweep_hybrid.py`
GitHub Issue: #669
The SIMPOINT_BEGIN should do nothing by default since it might be used
in various cases.
In
[https://www.mail-archive.com/gem5-users@gem5.org/msg22383.html](mailing
list), a user discovered a bug with the current
`simpoints-se-restore.py` example.
The bug is caused by the default behavior of the SIMPOINT_BEGIN exit
event.
When taking a checkpoint with `simpoints-se-checkpoint.py`, it stores
the future exit event scheduled at the beginning of the simulation. I
did not notice this when I wrote and tested the example script due to
the long print out log and my custom handler of the SIMPOINT_BEGIN exit
event.
In the restoring, the SIMPOINT_BEGIN exit event was triggered right
before the region end, so it resets the stats before the final stats
dump. Therefore, the simulation time is 0 as the user discovered.
This patch should fix this bug.
Change-Id: I800dfbd28d7b2c842864a1ab7d84b8f8e17b9b3c
This PR implements FEAT_MPAM on the CPU side. We define a MPAM system
registers and a mechanism
for tagging memory requests with the MPAM information bundle as
specified in existing documentation [1].
What this PR is *not* covering is the MPAM implementation in a MSC
(Memory System Component).
Which means at the moment it's only possible to have static partitioning
schemes (via the PartitioningPolicies
already part of gem5) and there is currently no way to dynamically
program partitions at runtime.
[1]: https://developer.arm.com/documentation/ddi0487/latest/
Quote from change[1]
> The RISC-V spec clarifies the CSR instruction operation, some of them
shall not read or write CSR by the hints of RD/RS1/uimm, but the
original version use the 'data != oldData' condition to determine
whether write or not, and always read CSR first.
See CSR instruction in spec:
Section 9.1 Page 56 of
https://github.com/riscv/riscv-isa-manual/releases/download/Ratified-IMAFDQC/riscv-spec-20191213.pdf
|||Register operand|||
|--- |--- |--- |--- |--- |
|Instruction|rd is x0|rs1 is x0|Reads CSR|Writes CSR|
|CSRRW|Yes|-|No|Yes|
|CSRRW|No|-|Yes|Yes|
|CSRRS/CSRRC|-|Yes|Yes|No|
|CSRRS/CSRRC|-|No|Yes|Yes|
|||Immediate operand|||
|Instruction|rd is x0|uimm = 0|Reads CSR|Writes
CSR|
|CSRRWI|Yes|-|No|Yes|
|CSRRWI|No|-|Yes|Yes|
|CSRRSI/CSRRCI|-|Yes|Yes|No|
|CSRRSI/CSRRCI|-|No|Yes|Yes|
The issue cause the ubuntu hanging because we shared the same status CSR
with `mstatus`, `sstatus` and `ustatus` and interrupt enabling CSR with
mip, sip and uip. We may need to read origin CSR without effect of
unmask bits to avoid override the bits of other CSR. Now the ubuntu can
work after the patch merged.
[1] https://gem5-review.googlesource.com/c/public/gem5/+/67717
The destination select should take a value of the selection size (dword,
word, or byte) starting at bit 0, move that to the selected destination,
and then apply the unused constraint (DST_U) to the remaining word or
bytes. Currently the code is selecting the word/byte currently being
iterated over, rather than the least significant word/byte. As a result,
any selection that is not word 0 or byte 0 will be replaced with the
original destination value at those bits. This results in the wrong
value.
This commit changes the orig bits to be the original dest value at the
lowest word / byte location. Tested with the mfma_i32_16x16x16i8 example
which uses an SDWA V_OR_B32 to pack i8 values into VGPRs for the MFMA.
Change-Id: I54ed819479a25fa9276d29a8f14f0fea7fd71afe
