The physical address has already been set (it's read earlier in the
function), and so doesn't need to be set again. Reading the virtual
address can cause an assert if the virtual address had never been set in
the first place, for example when an access comes from KVM which might
give you an access to complete which is based on a physical address
only.
Change-Id: Ic46a40b1a94235538b5bd53065e5019273b3d3f3
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/29172
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Reviewed-by: Pouya Fotouhi <pfotouhi@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>
If the address space is changed (by writing to SATP), it can happen that
a page table walk is in progress. Previously, this failed if the ASID
changed, because we then used the wrong ASID for the lookup.
This commit makes sure that we don't access CSRs after the beginning of
the walk by loading SATP, STATUS, and PRV at the beginning.
Change-Id: I8c184c7ae7dd44d78e881bb5ec8d430dd480849c
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/28447
Maintainer: Bobby R. Bruce <bbruce@ucdavis.edu>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Decoder: gpu_decoder.hh and decoder.cc:
The decoder is defined in these files. The decoder
is implemented as a lookup table of function pointers
where each decode function will decode to a unique
ISA instruction, or do some sub-decoding to infer
the next decode function to call.
The format for each OP encoding is defined in the
header file.
Registers:
registers.[hh|cc] define the special registers and
operand selector values, which are used to map
operands to registers/special values. many
convenience functions are also provides to determine
the source/type of an operand, for example vector
vs. scalar, register operand vs. constant, etc.
GPU ISA:
Some special GPU ISA state is maintained in gpu_isa.hh
and isa.cc. This class is used to hold some special
registers and values that can be used as operands
by ISA instructions. Eventually more ISA-specific
state should be moved here, and out of the WF class.
Vector Operands:
The operands for GCN3 instructions are defined in
operand.hh. This file defines both scalar and
vector operands wth GCN3 specific semantics. The
vector operand class is desgned around the generic
vec_reg.hh that is already present in gem5.
Instructions:
The GCN3 instructions are defined and implemented
throughout gpu_static_inst.[hh|cc], instructions.[hh|cc],
op_encodings.[hh|cc], and inst_util.hh. GCN3 instructions
all fall under one of the OP encoding types; for example
scalar memory operands are of the type SMEM, vector
ALU instructions can be VOP3, VOP2, etc. The base code
common to all instructions of a certain OP encoding type
is implemented in the OP encodings files, which includes
operand information, disassembly methods, encoding type,
etc.
Each individual ISA isntruction is implemented as
a class object in instructions.[hh|cc] and are derived
from one of the OP encoding types. The instructions.cc
file is primarily for the execute() methods of each
individual instruction, and the header file provides
the class definition and a few instruction specific
API calls.
Note that these instruction classes were auto-generated
but not using the gem5 ISA description language. A
custom ISA description was used and that cannot be released
publicly, therefore we are providing them already in C++.
Change-Id: I14d2a02d6b87109f41341c8f50a69a2cca9f3d14
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/28127
Reviewed-by: Matt Sinclair <mattdsinclair@gmail.com>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Anthony Gutierrez <anthony.gutierrez@amd.com>
Tested-by: kokoro <noreply+kokoro@google.com>
According to the debugging spec (page 47), a debugger can test which
triggers are enabled by writing 0 to TSELECT and reading it back. If a
different value is read, the trigger is not supported.
Therefore, we currently always set a different value to indicate that
we do not support any triggers.
Change-Id: If222e913c4517adb2da4f6f0ffeedb4e4808a586
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/25659
Tested-by: kokoro <noreply+kokoro@google.com>
Tested-by: Gem5 Cloud Project GCB service account <345032938727@cloudbuild.gserviceaccount.com>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
According to the privileged ISA spec, SEPC[0]/MEPC[0] reads always 0
and SEPC[1]/MEPC[1] reads 0 if the compressed extension is disabled.
Additionally, the compressed extension can only be disabled if the next
instruction is 4-byte aligned.
Change-Id: I590c05e4000b59a5ba283f47933f7a92959d8e38
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/25658
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
According to page 57 in the RISC-V manual, CSR accesses "need to be
performed in program order with respect to those instructions whose
execution behavior is affected by the state of the accessed CSR".
Thus, we need to make them SerializeAfter to ensure that the following
instructions are executed with the potential changes to the CSR. In
theory, we could be smarter here by only considering write accesses to
CSRs and considering the following instructions, but for now we simply
serialize for every CSR access.
Change-Id: I69391fccaec31c34d944c55bac2f04d37947ebfe
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/25655
Tested-by: kokoro <noreply+kokoro@google.com>
Tested-by: Gem5 Cloud Project GCB service account <345032938727@cloudbuild.gserviceaccount.com>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
That is, RISC-V has now a TLB and page table walker for Sv39 paging
according to the privileged ISA 1.11.
Both the TLB and PT walker are based on x86 (the code duplication of the
page table walkers will be reduced by a separate commit).
Change-Id: I5e29683bdd40c0d32c06e4d75a8382bf313f2086
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/25647
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
This test covers the templates which attempt to classify types, but not the
actual gathering of arguments of distribution of return values. As before, we
can't really use standard C++ to accurately test for HFAs and HVAs, so we stick
with approximating them by detecting arrays of the right types.
For example, I think technically we should also accept a struct with only 4
float members, but c++ templates aren't able to match against types in that way
as far as I know.
Change-Id: I1d7756a964a86c0c5ea13e068a5fc74603e14e30
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/28268
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Maintainer: Giacomo Travaglini <giacomo.travaglini@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
The templates which checked for short vectors, and our approximation of
HFA, HVA and HXA types were not correct. This change actually simplifies
them along with getting them to produce correct results. In the case of
HXA, there was a logic bug where an && was used where an || was
intended.
There may still be bugs in the actual collection of arguments and
setting of return values since those aspects are harder to test.
Change-Id: Ice3177205a98c678ecb43ba600813b3909c44e6b
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/28267
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Maintainer: Giacomo Travaglini <giacomo.travaglini@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
SVE half-precision floating-point instructions support only IEEE
754-2008 half-precision format and ignore the value of the FPCR.AHP bit,
behaving as if it has an Effective value of 0.
This patch is addressing this by masking the FPSCR.AHB bit before
passing it to fplib.
Change-Id: I1432fc3f7fefb81445fe042ae7d681f5cec40e64
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/28108
Tested-by: kokoro <noreply+kokoro@google.com>
This Patch will fix the alignment problem that appears sometimes
when we try to create a view of 128 bits over the VecRegContainer
object.
That container is initially created as std::array<uint8_t, SIZE>, so
there is no obligation to be aligned to 16 bytes. This patches forces
all containers to be aligned to 16 bytes.
The problem has been observed in the Jira Issue:
https://gem5.atlassian.net/browse/GEM5-320
Change-Id: Id9fdd427bd7a4dc904edd519f31cc29c5b29c5e6
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/27968
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Reviewed-by: Ciro Santilli <ciro.santilli@arm.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>
The components in base/loader were moved into a namespace called
Loader. This will make it easier to add loader components with fairly
short natural names which don't invite name collisions.
gem5 should use namespaces more in general for that reason and to make
it easier to write independent components without having to worry about
name collisions being added in the future.
Unfortunately this namespace has the same name as a class used to load
an object file into a process object. These names can be disambiguated
because the Process loader is inside the Process scope and the Loader
namespace is at global scope, but it's still confusing to read.
Fortunately, this shouldn't last for very long since the responsibility
for loading Processes is going to move to a fake OS object which will
expect to load a particular type of Process, for instance, fake 64 bit
x86 linux will load either 32 or 64 bit x86 processes.
That means that the capability to feed any binary that matches the
current build into gem5 and have gem5 figure out what to do with it
will likely be going away in the future. That's likely for the best,
since it will force users to be more explicit about what they're trying
to do, ie what OS they want to try to load a given binary, and also
will prevent loading two or more Processes which are for different OSes
to the same system, something that's possible today as far as I know
since there are no consistency checks.
Change-Id: Iea0012e98f39f5e20a7c351b78cdff9401f5e326
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/24783
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>
This is specialized per arch, and the Workload class is the only thing
actually using it. It doesn't make any sense to dispatch those calls
over to the System object, especially since that was, in most cases,
the only reason an ISA specific system class even still existed.
After this change, only ARM still has an architecture specific System
class.
Change-Id: I81b6c4db14b612bff8840157cfc56393370095e2
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/24287
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
This generalized Workload SimObject is not geared towards FS or SE
simulations, although currently it's only used in FS. This gets rid
of the ARM specific highestELIs64 property (from the workload, not the
system) and replaces it with a generic getArch.
The old globally accessible kernel symtab has been replaced with a
symtab accessor which takes a ThreadContext *. The parameter isn't used
for anything for now, but in cases where there might be multiple
symbol tables to choose from (kernel vs. current user space?) the
method will now be able to distinguish which to use. This also makes
it possible for the workload to manage its symbol table with whatever
policy makes sense for it.
That method returns a const SymbolTable * since most of the time the
symbol table doesn't need to be modified. In the one case where an
external entity needs to modify the table, two pseudo instructions,
the table to modify isn't necessarily the one that's currently active.
For instance, the pseudo instruction will likely execute in user space,
but might be intended to add a symbol to the kernel in case something
like a module was loaded.
To support that usage, the workload has a generic "insertSymbol" method
which will insert the symbol in the table that "makes sense". There is
a lot of ambiguity what that means, but it's no less ambiguous than
today where we're only saved by the fact that there is generally only
one active symbol table to worry about.
This change also introduces a KernelWorkload SimObject class which
inherits from Workload and adds in kernel related members for cases
where the kernel is specified in the config and loaded by gem5 itself.
That's the common case, but the base Workload class would be used
directly when, for instance, doing a baremetal simulation or if the
kernel is loaded by software within the simulation as is the case for
SPARC FS.
Because a given architecture specific workload class needs to inherit
from either Workload or KernelWorkload, this change removes the
ability to boot ARM without a kernel. This ability should be restored
in the future.
To make having or not having a kernel more flexible, the kernel
specific members of the KernelWorkload should be factored out into
their own object which can then be attached to a workload through a
(potentially unused) property rather than inheritance.
Change-Id: Idf72615260266d7b4478d20d4035ed5a1e7aa241
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/24283
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>
It is assumed that the semihosting configuration uses the semihosting
number which includes gem5's pseudo insts.
Given the complexity and likely limitted value of letting the user
arbitrarily configure fast model's semihosting, and the fact that that
semihosting implementation would compete with gem5's own, those
parameters should be removed from python and set purely within C++.
Also note that if this semihosting support is used, the System object
needs to have an ArmSemihosting object installed to handle the calls.
Change-Id: I8e1de7717c9784dc7873795acd0a06389ec527b1
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/25623
Tested-by: Gem5 Cloud Project GCB service account <345032938727@cloudbuild.gserviceaccount.com>
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>
The GuestABI used to call the system-calls infers the size of values
read from the registers based on the function signature of the system
call. For mmap this was causing offset to be truncated to a 32-bit
value. In the GPUComputeDriver mmap, the offset must be a 64-bit
value. This fixes a bug where the doorbell memory was not setup and
causing GPU applications to fail.
Change-Id: I75d9b32c0470d1907c68826ef81cf6cd46f60ea7
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/27367
Tested-by: Gem5 Cloud Project GCB service account <345032938727@cloudbuild.gserviceaccount.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Matthew Poremba <matthew.poremba@amd.com>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
This simplifies the SPARC FS workload significantly, and removes
assumptions about what ROMs exist, where they go, etc. It removes
other components from the loop which don't have anything to contribute
as far as setting up the ROMs.
One side effect of this is that there isn't specialized support for
adding PC based events which would fire in the ROMs, but that was never
done and the files that were being used were flat binary blobs with no
symbols in the first place.
This also necessitates building a unified image which goes into the single
8MB ROM that is located at address 0xfff0000000. That is simply done
with the following commands:
dd if=/dev/zero of=t1000_rom.bin bs=1024 count=8192
dd if=reset_new.bin of=t1000_rom.bin
dd if=q_new.bin of=t1000_rom.bin bs=1024 seek=64
dd if=openboot_new.bin of=t1000_rom.bin bs=1024 seek=512
This results in an 8MB blob which can be loaded verbatim into the ROM.
Alternatively, and with some extra effort, an ELF file could be
constructed which had each of these components as segments, offset to the
right location in the ELF header. That would be slightly more work to set up,
but wouldn't waste space on regions of the image that are all zeroes.
Change-Id: Id4e08f4e047e7bd36a416c197a36be841eba4a15
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/27268
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: Gem5 Cloud Project GCB service account <345032938727@cloudbuild.gserviceaccount.com>
This is fixing switcheroo tests when using a PMU/GICv3. When you switch
cpus you usually instantiate multiple cpus at the beginning and you
switch them at runtime with the m5.switchCpus function.
Every cpu will have its own set of ThreadContexts/ISAs.
When you switch cpu/tc/isa, you need to update the tc/isa pointer
cached in the device model otherwise those will still reference
the switched out cpu.
Change-Id: I3aeee890286851189c3a8a4d378c83f32e973361
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/27713
Reviewed-by: Ciro Santilli <ciro.santilli@arm.com>
Tested-by: kokoro <noreply+kokoro@google.com>
