The PR https://github.com/gem5/gem5/pull/1316 changes the sign-extend
address generation. We also need to sign-extend the address when setting
the PC in enter/leave trap handler
Change-Id: I62d58a26dba0b0c64125fea8ac9376ebf55c4952
The number of register pins for the vector gather instructions was not
calculated correctly because the micro vl was not right. This caused
some micros to rename a new register instead of using a pinned one.
Previously, GPU L2 caches could be configured in either writeback or
writethrough mode when used in an APU. However, in a CPU+dGPU system,
only writethrough worked. This is mainly because in CPU+dGPU system, the
CPU sends either PCI or SDMA requests to transfer data from the GPU
memory to CPU. When L2 cache is configured to be writeback, the dirty
data resides in L2 when CPU transfers data from GPU memory. This leads
to the wrong version being transferred. A similar issue also crops up
when the GPU command processor reads kernel information before kernel
dispatch, only to incorrect data. This PR contains a set of commits that
fix both these issues.
The method is defined as const but the caller will actually modify the
content of the structure directly with the pointer in
BaseRemoteGDB::cmdRegW. The member access in the const method are
actually treated as const and will cause error if we use
reinterpret_cast instead.
Remove the const tag to align the expectation of the virtual method.
One of the perks of the previous TLB storage implementation [1] is that
its custom implementation of LRU exploited temporal locality to speed up
simulation performance
TlbEntry tmp_entry = *entry;
for (int i = idx; i > 0; i--)
table[i] = table[i - 1];
table[0] = tmp_entry;
return &table[0];
In other words the matching entry was placed as the first entry of the
TLB table (table[0], top of LRU stack). In this way a following lookup
would encounter it as the first entry while looping over the TLB table,
therefore massively reducing simulation time when temporal locality is
present
(most of TLB table loops would find a match in the first iteration).
int x = 0;
while (x < size) {
if (table[x].match(lookup_data)) {
With the new implementation we decouple TLB storage from the replacement
policy. The result is a more flexible implementation but with the
drawback of a slower lookup/search. We therefore we need to find another
way to exploit temporal locality. This patch addresses it by caching a
previously matched entry in the TLB table
[1]: https://github.com/gem5/gem5/blob/v24.0.0.0/src/arch/arm/tlb.cc
Change-Id: Id7dedf5411ea6f6724d1e4bdb51635417a6d5363
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
The MMU already stores a pointer to the release object, so it can query
it directly to check for PAN instead of relying on the slower HaveExt
helper
Change-Id: Ie3a186aa1d65955cff4a40871bde1ee78aa36ec0
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Two NetDest locally declared variables are using default constructor
instead of constructor with RubySystem pointer. This will cause asserts
when (1) garnet is used or (2) a protocol that uses `broadcast()` is
built.
Fix these two by passing the appropriate RubySystem pointers.
In our usecase, we'd like to intercept some gadgets in some gem5 ports,
and register them to a Python-level collection. The registered name is
the string from C++ constructor argument (portName), and it would be
great if we can access that from Python-level as well. This commit
enable this by exporting a py-binded method to access the portName.
Change-Id: I93398697536f27a52d3a1dd0e658fcb321b9e293
With this PR we replace the TlbEntry storage within the TLB from an
array of entries with a custom hardcoded FA indexing policy and LRU
replacement policy, into the flexible SetAssociative cache.
purifyTaggedAddr is known to be an expensive computation regardless of
the memoization we do, as it sits in the critical path from a host
performance point of view (instruction fetch).
In checkPermissions64 we compute it without really needing the tag
purification. The only place where it is used is to check for
PCAlignment, but the alignment checks the 3LSBs whereas a potential tag
would be stored in the most significant ones
Change-Id: I9f39db658c3575dcbacb5351813ff9bb3775046d
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
PR gem5#1453 left some unused variables in the ruby code that triggered
"unused variable" warnings found comiling ALL/gem5.opt to use the CHI
protocol. These have been removed.
In #1453, an `implicit_ctor` option was added for SLICC structures. This
was done to allow statements such as `NetDest tmp;` which now require a
non-default constructor without modifying every protocol. The new
`implicit_ctor` option converts the statement `NetDest tmp;` in SLICC to
`NetDest tmp(<implicit_ctor>);` in C++. This is problematic when doing
something like `NetDest tmp := getMachines(...);` which gets converted
to `NetDest tmp(<implicit_ctor) = getMachines(...);` as the constructor
doesn't return an object. Before #1453 NetDest had a default constructor
so there we no difference between a local variable definition and local
variable assignment.
This commit fixes this issue by checking in the LocalVariableAST if the
local variable is part of an assignment or not. If it is not part of an
assignment, the implicit_ctor is used. Otherwise, the assignment is
printed to the generated code.
Note that this is not done anywhere in the public code but should be
allowed for folks writing their own Ruby protocols who might otherwise
be confused why a simple assignment presents a compile error.
This commit addresses the requested changes. An additional
comment is added for clarification, the exception type is
changed, and a few of the error messages have been
modified.
Fix#1384.
MESI_Two_Level and MESI_Three_Level protocols are susceptible to LL/SC
livelocks when simulating boards with high core count.
This fix is based on MOESI_CMP_directory's implementation of locked
states, but tailors the solution to only apply it when a Load-Linked is
initiated.
There are two new states to act as locked states and stall any messages
leading to eviction:
* LLSC_E: equivalent to E state, go to E after timeout.
* LLSC_M: equivalent to M state, go to M after timeout.
The main new event is Load_Linked, which is very similar (in behavior)
to a Store, reusing several transient states. When a controller receives
the exclusive data, it differentiates a Load_Linked from a Store by
checking a new field added to the TBE: 'isLoadLinked'. It triggers a
different event when it is a Load_Linked, which in turn causes the
transition to one of the locked states.
The entire mechanism can be turned off by setting 'use_llsc_lock' to
false, and the amount of time to keep locked is defined by
'llsc_lock_timeout_latency'.
Change-Id: I13f415b6b7890d51d01f23001047d2363467a814
A previous PR mistakenly [1] replaced translateFunctional with
translateAtomic. This commit is reverting that
[1]: https://github.com/gem5/gem5/pull/1697
Change-Id: I945c3fe59cea36732d9f30109b950d4114aa8fad
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
This commit adds SE mode to RiscvBoard. RiscvDemoBoard has also
been modified as adding SE mode to RiscvBoard made the
overridden functions in RiscvDemoBoard obsolete.
This commit adds SE mode to X86Board. X86DemoBoard was also modified,
as functions that were previously needed to add SE mode to
X86DemoBoard were removed.
This PR adds a RiscvDemoBoard that can be used with both SE and FS
mode.This was tested using the workloads riscv-matrix-multiply-run for
SE and riscv-ubuntu-20.04-boot for FS. Two example config scripts have
also been added.
Add decoder and function of AArch32 VRINTN, VRINTX, VRINTA, VRINTZ,
VRINTM, and VRINTP (Advanced SIMD) instructions. Support both 16-bit and
32-bit variants.
Add vfpFPRint in vfp.hh to perform the behavior of round-to-integer.
Only support A32 encoding.
Change-Id: Icb9b6f71edf16ea14a439e15c480351cd8e1eb88
Fix#1682. Treat LEA as a BigLdStOp. BigLdStOps (as well as other Big*
x86 uops) do not have input dependencies on 32-/64-bit destinations. LEA
will still have input dependencies on 16-bit destinations. (LEA cannot
have an 8-bit destination.)
Change-Id: I5d0678e6bd79bfd6064941a89c6fe290750543c9
Moving the address translation logic outside of the ISA::setMiscReg will
allow it to return and potentially invoke a fault
upon execution of the AT instruction. This change affects AArch64 mode
only
Originally, the debug print for read/write to specific register name
will happen after reg.read() and reg.write(). However, there might be
other debug print or warning inside reg.read(), reg.write() which would
be confusing if this debug log happen after all other debug print inside
reg.read(), reg.write().
Creating this commit to change the order.
Starting with https://github.com/gem5/gem5/pull/1453 , some Ruby
structures require a block size be set
and other require a pointer to the Ruby system. This fixes some cases
which were not covered by the per-checkin tests but seen in daily+
tests. In particular:
- WriteMasks and PerfectCacheMemory must explicitly set a block size.
- NetDest and RubyProxyPort require RubySystem pointer.
- Classes inheriting Message now have a setRubySystem collecting all
objects that need a RubySystem pointer and this should be called in
the constructor of the Message.
This commit makes sure all of these happen. This should fix daily
arm_boot_tests and daily learning_gem5 tests.
Move AT instructions out of setMiscReg.
Modification includes:
- Add template for AT instructions in misc64.isa.
- Add decoder and execution of AT instruction in aarch64.isa and
data64.isa.
- Add AtOp64 and AtOp64Hub to perform the behavior of AT instructions.
Change-Id: I7e8b802421f7335203edb9f8d748ad8669954b8c
This PR adds the SMS prefetcher described in [this
](https://web.eecs.umich.edu/~twenisch/papers/isca06.pdf) paper.
This work was done in collaboration with @Setu-Gupta, and @xmlizhao
On branch sms
Changes to be committed:
modified: src/mem/cache/prefetch/Prefetcher.py
modified: src/mem/cache/prefetch/SConscript
new file: src/mem/cache/prefetch/sms.cc
new file: src/mem/cache/prefetch/sms.hh
Change-Id: I68d3bb6cf07385177d0f776fb958f652cfc41489
With this commit we replace the TlbEntry storage within the TLB from an
array of entries with a custom hardcoded FA indexing policy and LRU
replacement, into the flexible SetAssociative cache.
Change-Id: Ia74ff6962ac8195802b51dcc0caa516965f0ce37
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
KeyType definition is required if we want to store the TlbEntry
within an AssociativeCache. We could add an alias and keep the
Lookup name but this will just create extra confusion
Change-Id: Ib0b7c9529498f0f6f15ddd0e7cf3cec52966e8df
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
This is needed for compliance with the AssociativeCache
container. It will call the invalidate method when
invalidating the TLB entry
Change-Id: Idb1bc40b5aea8c475146700c81ab79d9980f745d
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
With this commit we record the page sizes of all valid
TLB entries in a TLB.
We update the set conservatively, therefore allowing
false positives but not false negatives.
This information will be used when doing a page size based
lookup. At the moment we don't strictly need it as we
iterate over all TLB entries (the TLB implements a fully
associative cache) and if we find multiple matches, it means
we have stored some partial translations.
The existing logic is prioritizing complete translations
over partial translations and among the latter, late stage
translations over early stage (with the idea to minimize
the number of walks).
The "iterate once over the entire TLB and record all matches"
won't work well when we shift from a fully associative
TLB into a set associative. With the introduction of the
aforementioned set, we can do page size based lookups,
so we can explicitly lookup the TLB for a specific page size
therefore looking into the appropriate set for a match
Change-Id: If77853373792d6a5ec84cf1909ee5eb567f3d0e4
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Some ISAs (like Arm) have moved most of the translation logic into
the MMU and use the TLB simply as translation storage. It makes
sense to use the MMU debug flag for that logic and reduce the
scope of the TLB flag to TLB insertion/hits/misses
Change-Id: I2a164545c711d83d3e87075b0cb5c279eed274c9
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
This commit is moving some MMU methods definition in the
source file from the header to avoid including tlb.hh
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
Change-Id: I8fb1aeccd9c38c48b09583b4dc5d152acd09c3e6
It is a simple enum to distinguish between short and big
descriptors. By moving it away from the ArmFault we can
avoid including fault.hh from mmu.hh
Change-Id: Ib556b577c62f5ea3e4c8c9e0d4560a3e99c96778
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>
