The behavior of WFI is to cause minor to cease evaluating
pipeline logic until an interrupt is observed, however
a user may wish to drain the system while a core is sleeping
due to a WFI. This patch makes WFI drain. If an actual
drain occurs during a WFI, the CPU is already drained and will
immediately be ready for swapping, checkpointing, etc. This
should not negatively impact performance as WFI instructions
are 'stream-changing' (treated like unpredicted branches), so
all remaining instructions are wrong-path and will be squashed
rapidly.
Change-Id: I63833d5acb53d8dde78f9f0c9611de0ece385e45
This patch adds SMT support to the MinorCPU. Currently
RoundRobin or Random thread scheduling are supported.
Change-Id: I91faf39ff881af5918cca05051829fc6261f20e3
Make it so that getInterrupt *always* returns an interrupt if
checkInterrupts() returns true. This fixes/simplifies handling
of interrupts on the SMT FS CPUs (currently minor).
This patch adds a total() function to the Vector2D
stat type. Similar to other stats such as Scalar or
Vector it is useful to be able to read the total for
a given stat.
This patch fixes a bug in etherswitch. When a packet gets inserted
in the output fifo, the txEvent has to always be reschedule,
not only when an event is already scheduled. This can raise
the assertion in the reschedule function.
Don't consult the TLB test interface for PA's returned by functional
translations by the AT instruction. We implement this by chaning the
ISA code to synthesize 0-length functional reads for the TLB lookup.
The TLB then bypasses the final PA check in the tester if the size is
zero.
Change-Id: I2487b7f829cea88c37e229e9fc7a4543aced961b
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
The ELF loader currently has an assertion that checks if the size of a
loaded .text secion is non-zero. This is useful in the general case as
an empty text section normally indicates that there is something
strange with the ELF file. However, asserting isn't very useful. This
changeset converts the assert into a warning that tells the user that
something strange is happening.
Change-Id: I313e17847b50a0eca00f6bd00a54c610d626c0f0
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Currently garnet will not run due to double statistic registration of new
stats in ClockedObject. This occurs because a temporary array named 'cls'
is being added as a child to garnet internal and external link SimObjects.
This patch simply renames the temporary array which prevents it from
being added as a child object and avoids the assertion that a statistic
was already registered.
Committed by Jason Lowe-Power <jason@lowepower.com>
Sync DRAMPower to external tool
This patch syncs the DRAMPower library of gem5 to the external
one on github (https://github.com/ravenrd/DRAMPower) of which
I am a maintainer.
The version used is the commit:
902a00a1797c48a9df97ec88868f20e847680ae6
from 07. May. 2016.
Committed by Jason Lowe-Power <jason@lowepower.com>
In this new hmc configuration we have used the existing components in gem5
mainly [SerialLink] [NoncoherentXbar]& [DRAMCtrl] to define 3 different
architecture for HMC.
Highlights
1- It explores 3 different HMC architectures
2- It creates 4-HMC crossbars and attaches 16 vault controllers with it.
This will connect vaults to serial links
3- From the previous version, HMCController with round robin funtionality
is being removed and all the serial links are being accessible directly
from user ports
4- Latency incorporated by HMCController (in previous version) is being
added to SerialLink
Committed by Jason Lowe-Power <jason@lowepower.com>
This patch changes how the embedded swig code is loaded to ensure that
gem5 works with swig 3.0.9. For Python 2.7 and above, swig 3.0.9 now
relies on importlib, and actually looks in the appropriate packages,
even for the wrapped C code. However, the swig wrapper does not
explicitly place the module in the right package (it just calls
Py_InitModule), and we have to take explicit action to ensure that the
swig code can be loaded. This patch adds the information to the
generated wrappers and the appropriate calls to set the context as
part of the swig initialisation.
Previous versions of swig used to fall back on looking in the global
namespace for the wrappers (and still do for Python 2.6), but
technically things should not work without the functionality in this
patch.
Previously when we initialized the TLB we would allocate a number of
TLB entries which would be marked as valid. As a result the TLB
contained an entry which would be considered a valid entry for the 0
page.
Change-Id: I23ace86426a171a4f6200ebeb29ad57c21647036
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
The use of array tuples, requires an explicit include of the array library
Change-Id: I06730051777a97edf80e41a5604184b387b12239
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
The snoop filter handles requests in two steps which preceed and
follow the call to send the packet downstream. An address mapper could
possibly change the address of the packet when it is sent downstream
breaking the snoop filter assumption that the address is unchanged
Change-Id: Ib2db755e9ebef4f2f7c0169a46b1b11185ffbe79
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
The traffic generator currently resolves relative trace paths relative
to gem5's current working directory. This can lead to surprising
results for relative paths where the expectation would normally be
that they are resolved relative to the configuration file. This
changeset implements config-relative trace file lookups. The old
behavior is kept as a fallback for configs that expect that behavior.
Change-Id: I1bda4e16725842666ffc37dcb6838c23a6ff138c
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Add helper functions to dump the guest kernel's dmesg buffer to a text
file in m5out. This functionality is split into two parts. First, a
dmesg dump function that can be used in other places:
void Linux::dumpDmesg(ThreadContext *, std::ostream &)
This function is used to implement two PCEvents: DmesgDumpEvent and
KernelPanic event. The only difference between the two is that the
latter produces a gem5 panic instead of a warning in addition to
dumping the kernel log.
Change-Id: I6d2af1d666ace57124089648ea906f6c787ac63c
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Gabor Dozsa <gabor.dozsa@arm.com>
The SymbolTable class currently assumes that at most one symbol can
point to a given address. If multiple symbols point to the same
address, only the first one gets added to the internal symbol table
since there is already a match in the address table.
This changeset converts the address table from a map into a multimap
to be able to handle cases where an address maps to multiple
symbols. Additionally, the insert method is changed to not fail if
there is a match in the address table.
Change-Id: I6b4f1d5560c21e49a4af33220efb2a8302961768
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Andreas Hansson <andreas.hansson@arm.com>
Reviewed-by: Gabor Dozsa <gabor.dozsa@arm.com>
There is a mismatch between DataType and SrcDataType in constructing
Atomic ST instruction. The mismatch causes atomic_store and
atomic_store_explicit function to store incorrect value in memory.
Eliminate the VSZ constant that defined the Wavefront size (in numbers of work
items); replaced it with a parameter in the GPU.py configuration script.
Changed all data structures dependent on the Wavefront size to be dynamically
sized. Legal values of Wavefront size are 16, 32, 64 for now and checked at
initialization time.
This patch fixes the order that packets gets pushed into the output fifo
of etherswitch. If two packets arrive at the same tick to the etherswitch,
we sort and push them based on their source port id.
In dist-gem5 simulations, if there is no ordering inforced while two
packets arrive at the same tick, it can lead to non-deterministic simulations
Committed by Jason Lowe-Power <power.jg@gmail.com>
mathexpr.hh uses std::function<> but was not including the appropriate
header, which resulted in an error
build/ARM/sim/mathexpr.hh:51:18: error: 'function' in namespace 'std'
does not name a template type
typedef std::function<double(std::string)> EvalCallback;
This commit adds the missing include.
Change-Id: I6c01d77d4354c6de838538f137a38f75f9866166
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
A lot of objects seem to request no-op power transitions which
currently results in large amounts of warnings. These warnings are
benign and risk hiding more serious warnings. Make the warning a
warn_once to prevent console flooding.
Change-Id: I86c74b4224b167f14469250ef86ab69fde7a227e
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
This patch makes thermal models use the power figures
calculated by power models. Since there is a circular
dependency between power and thermal (and thermal was
pushed before) this patch closes that loop.
Change-Id: I8bd5acf6a5026fdbbcfac47e33d27397f24a6f7d
Reviewed-by: Stephan Diestelhorst <stephan.diestelhorst@arm.com>
This patch adds some basic support for power models in gem5.
The power interface is defined so it can interact with thermal
models as well. It implements a simple power evaluator that
can be used for simple power models that express power in the
form of a math expression. These expressions can use stats
within the same SimObject (or down its hierarchy) and some
magic variables such as "temp" for temperature.
In future patches we will extend this functionality to allow
slightly more complex expressions.
The model allows it to be extended to use other kinds of models.
Change-Id: I76752f9638b6815e229fd74cdcb7721a305cbc4b
Add functionality to the BaseCPU that will put the entire CPU
into a low-power idle state whenever all threads in it are idle.
Change-Id: I984d1656eb0a4863c87ceacd773d2d10de5cfd2b
The power stats are currently very noisy even if no power model has
been loaded. Silence stats that are either zero or nan.
Change-Id: I7d0220c2fcf01131084a219228f140cfaddaf95b
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Add 4 power states to the ClockedObject, provides necessary access
functions to check and update the power state. Default power state
is UNDEFINED, it is responsibility of the respective simulation
model to provide the startup state and any other logic for state
change. Add number of transition stat. Add distribution of time
spent in clock gated state. Add power state residency stat. Add
dump call back function to allow stats update of distribution
and residency stats.
Change-Id: Id086090a2ed720c9fcb37812a3c98f0f724907c6
Fixing an issue with regStats not calling the parent class method
for most SimObjects in Gem5. This causes issues if one adds new
stats in the base class (since they are never initialized properly!).
Change-Id: Iebc5aa66f58816ef4295dc8e48a357558d76a77c
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
We want to extend the stats of objects hierarchically and thus it is necessary
to register the statistics of the base-class(es), as well. For now, these are
empty, but generic stats will be added there.
Patch originally provided by Akash Bagdia at ARM Ltd.
This implements SwapReq for Ruby memory.
A SwapReq should be treated like a write, except that the response
packet contains the overwritten data.
Note that, in particular, the conditional checking for isStore/isLoad
needs to be reversed, as a SwapReq is both.
In particular, when EL0 is in AArch32 but EL1 is AArch64, AArch64
memory translation must be used. This is essential for typical
AArch64/32 interworking use cases.
The ERET instruction doesn't set PSTATE correctly in some cases
(particularly when returning to aarch32 code). Among other things,
this breaks EL0 thumb code when using a 64-bit kernel. This changeset
updates the ERET implementation to match the ARM ARM.
Change-Id: I408e7c69a23cce437859313dfe84e68744b07c98
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Nathanael Premillieu <nathanael.premillieu@arm.com>
The current implementation of aarch32 FP/SIMD in gem5 assumes that EL1
and higher are all 32-bit. This breaks interprocessing since an
aarch64 EL1 uses different enable/disable bits. This change updates
the permission checks to according to what is prescribed by the ARM
ARM.
Change-Id: Icdcef31b00644cfeebec00216b3993aa1de12b88
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Mitch Hayenga <mitch.hayenga@arm.com>
Reviewed-by: Nathanael Premillieu <nathanael.premillieu@arm.com>
LPAE has been tested with Linux 4.4 and seems to work just fine. Let's
enable it by default.
Change-Id: Id88c6e3c91ae9c353279d42f2aa1f8a78485bd32
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Gabor Dozsa <gabor.dozsa@arm.com>
According to the ARM ARM (see AArch32.TranslateAddress in the
pseudocode library), the TLB should be operating in aarch64 mode if
the EL0 is aarch32 and EL1 is aarch64. This is currently not the case
in gem5, which breaks 64/32 interprocessing. Update the check to match
the reference manual.
Change-Id: I6f1444d57c0e2eb5f8880f513f33a9197b7cb2ce
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Mitch Hayenga <mitch.hayenga@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
After reaching consensus on the mailing list, this patch officially
makes gcc 4.8 the minimum.
A few checks in the SConstruct are cleaned up as a result. This patch
also adds "-fno-omit-frame-pointer" when using ASAN (which is part of
the gcc/clang recommended flags).
We currently check the current state instead of the state of the
target EL when determining how we report a fault. This breaks
interprocessing since EL0 in aarch32 would report its fault status
using the aarch32 registers even if EL1 is in aarch64. Fix this to
report the fault using the format of the target EL.
Change-Id: Ic080267ac210783d1e01c722a4ddaa687dce280e
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Mitch Hayenga <mitch.hayenga@arm.com>
The TLB currently assumes that the pxn bit in an LPAE page descriptor
disables execution from unprivileged mode. However, according to the
architecture manual, this bit should disable execution from privileged
modes. Update the TLB implementation to reflect this behavior.
Change-Id: I7f1bb232d7a94a93fd601a9230223195ac952947
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
A lot of code assumes that it is possible to test what the highest EL
is and if it is 64 bit. These calls currently don't work in SE mode
since they rely on an instance of an ArmSystem.
Change-Id: I0d1f261926a66ce3dc4fa116845ffb2a081446f2
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Nathanael Premillieu <nathanael.premillieu@arm.com>
This patch fixes a memory leak where deferred snoop packets never got
deallocated. On the call to MSHR::handleSnoop these snoops were
treated as if a response will be sent, as the MSHR was
pendingModified. Consequently, a copy of the packet was created and
added to the MSHR targets. However, an preceeding target to the same
MSHR, originally from a CPU, was serviced before the snoop, and caused
the block to be invalidated. This happens for ReadExReq and
UpgradeReq.
Note that the original snoop will receive a response, just not from
the cache in question, but instead from the cache upstream that issued
the ReadExReq or UpgradeReq.
Change-Id: I4ac012fbc8a46cf693ca390fe9476105d444e6f4
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Make it possible to disable gem5 gic extensions by setting the
gem5_extensions param to False from Python.
Change-Id: Icb255105925ef49891d69cc9fe5cc55578ca066d
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Geoffrey Blake <geoffrey.blake@arm.com>
This patch adds a progress check to the TrafficGen so that it is
easier to detect deadlock scenarios where the generator gets stuck
waiting for a retry, and makes no further progress.
Change-Id: Ifb8779ad0939f52c0518d0e867bac73f99b82e2b
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Radhika Jagtap <radhika.jagtap@arm.com>
This patch changes the flow control for HSHR::handleSnoop to ensure
that we only set cacheResponding on the snoop packet if we are
actually responding. This avoids situations where a responder is
stalling indefinitely on a response that never arrives.
Change-Id: I691dd01755b614b30203581aa74fc743b350eacc
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
This patch fixes the type of the unique_ptr instances, to ensure that
the data that is allocated with new[] is also deleted with
delete[]. The issue was highlighted by ASAN.
Change-Id: I2c5510424959d862a9954d83e728d901bb18d309
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Reviewed-by: Stephan Diestelhorst <stephan.diestelhorst@arm.com>
This patch fixes an issue identified by ASAN where the Neon64Load
operation assumes the packet always contains 16 bytes.
Change-Id: If24a7e461d60cb80970dfbe61d923d7d56926698
Reviewed-by: Giacomo Gabrielli <giacomo.gabrielli@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
As identified by clang-3.8, there was a superfluous loop increment in
the flash device which is now removed.
Change-Id: If46a1c4f72d3d4c9f219124030894ca433c790af
Reviewed-by: Rene De Jong <rene.dejong@arm.com>
According to the Intel Multi Processor Specification rev 1.4 (-006) (*),
section 4.3.2 Bus Entries, Bus type strings are >>6-character ASCII
(blank-filled) strings<<.
This patch properly pads the entries with the missing spaces at the end.
(*) http://www.intel.com/design/pentium/datashts/24201606.pdf
Committed by Jason Lowe-Power <power.jg@gmail.com>
Given we do not simulate a FIFO currently there are only two states
we can be in upon read: empty or full. Properly signal the latter.
Add and sort constants for states in the header file.
Committed by Jason Lowe-Power <power.jg@gmail.com>
Registers are 0x10 and not 0x8 apart. The latter leads to invalid
calculations of index in array which in turn means that we will not
find the interrupt we were looking (been notified) for in the OS.
Committed by Jason Lowe-Power <power.jg@gmail.com>
VirtIO spec < 1.0 demands IOREG to be used on PCI and not memory mapped.
Set the correct bit on the PCI address accordingly.
Committed by Jason Lowe-Power <power.jg@gmail.com>
the n_reg field in the GPUDynInst is not currently set in the constructor.
if it is not set externally, there are assertion failures that may occur
if the random value it gets is just right. here we set it to 0 by default.
The GICv2 has a new and slightly more consistent register
naming. Update gem5's GIC register names to match the new
documentation.
Change-Id: I8ef114eee8a95bf0b88b37c18a18e137be78675a
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
The LinuxArmSystem class normally provides support for panicing gem5
if the simulated kernel panics. When this is turned off (default),
gem5 uses a BreakPCEvent to provide a debugger hook into the simulator
when the kernel crashes. This hook unconditionally kills gem5 with a
SIGTRAP unless gem5 is compiled in fast mode. This is undesirable
since the panic_on_panic param already provides similar functionality.
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Add support for overriding the number of interrupt lines in the ARM
KvmGic.
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Radhika Jagtap <radhika.jagtap@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Factor out the kernel device wrapper from the KvmGIC and put it in a
separate class. This will simplify a future kernel/gem5 hybrid GIC.
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Radhika Jagtap <radhika.jagtap@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
The Terminal device currently uses the peek functionality in gem5's
circular buffer implementation to send existing buffered content on
the terminal when a new client attaches. This functionallity is
however not implemented correctly and re-sends the same block multiple
time.
Add the required functionality to peek with an offset into the
circular buffer and change the Terminal::accept() implementation to
send the buffered contents.
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Radhika Jagtap <radhika.jagtap@arm.com>
Reviewed-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Allow usage of packet class in ruby for convenience purposes. This may be
used to access members of the packet/request class (e.g., via helper
functions) and/or push protocol specific information to the packets
SenderState without needing to modify SLICC types and protocols in multiple
locations.
This patch removes the write-queue entry tracking previously used for
uncacheable writes. The write-queue entry is now deallocated as soon
as the packet is sent. As a result we also forego the stats for
uncacheable writes. Additionally, there is no longer a need to attach
the write-queue entry to the packet.
Ruby's controller block_on behavior aimed to block MessageBuffer requests into
SLICC controllers when a Locked_RMW was in flight. Unfortunately, this
functionality only partially works: When non-Locked_RMW memory accesses are
issued to the sequencer to an address with an in-flight Locked_RMW, the
sequencer may pass those accesses through to the controller. At the controller,
a number of incorrect activities can occur depending on the protocol. In
MOESI_hammer, for example, an intermediate IFETCH will cause an L1D to L2
transfer, which cannot be serviced, because the block_on functionality blocks
the trigger queue, resulting in a deadlock. Further, if an intermediate store
arrives (e.g. from a separate SMT thread), the sequencer allows the request
through to the controller, and the atomicity of the Locked_RMW may be broken.
To avoid these problems, disallow the Sequencer from passing any memory
accesses to the controller besides Locked_RMW_Write when a Locked_RMW is in-
flight.
Remve the assertion that we always need to add a delta larger than
zero as that does not seem to be true when we hit it in the
'PMU reset cycle counter to zero' case.
Committed by Jason Lowe-Power <power.jg@gmail.com>
A few warnings (and thus errors) pop up after being added to -Wall:
1. -Wmisleading-indentation
In the auto-generated code there were instances of if/else blocks that
were not indented to gcc's liking. This is addressed by adding braces.
2. -Wshift-negative-value
gcc is clever enougn to consider ~0 a negative constant, and
rightfully complains. This is addressed by using mask() which
explicitly casts to unsigned before shifting.
That is all. Porting done.
Queued prefetcher entries now count with a priority field. The idea is to
add packets ordered by priority and then by age.
For the existing algorithms in which priority doesn't make sense, it is set
to 0 for all deferred packets in the queue.
Some common functionality added to the base prefetcher, mainly dealing with
extracting the block address, page address, block index inside the page and
some other information that can be inferred from the block address. This is
used for some prefetching algorithms, and having the methods in the base,
as well as the block size and other information is the sensible way.
In general, the ThreadID parameter is unnecessary in the memory system
as the ContextID is what is used for the purposes of locks/wakeups.
Since we allocate sequential ContextIDs for each thread on MT-enabled
CPUs, ThreadID is unnecessary as the CPUs can identify the requesting
thread through sideband info (SenderState / LSQ entries) or ContextID
offset from the base ContextID for a cpu.
This is a re-spin of 20264eb after the revert (bd1c6789) and includes
some fixes of that commit.
This patch adds a configurable indirect branch predictor that can be indexed
by a combination of GHR and path history hashes. Implements the functionality
described in:
"Target prediction for indirect jumps" by Chang, Hao, and Patt
http://dl.acm.org/citation.cfm?id=264209
This is a re-spin of fb9d142 after the revert (bd1c6789).
The extant BTB code doesn't hash on the thread id but does check the
thread id for 'btb hits'. This results in 1-thread of a multi-threaded
workload taking a BTB entry, and all other threads missing for the same branch
missing.
This changeset updates the dot output to bail out if it is unable to
resolve the voltage or clock domains (which will cause it to raise an
AttributeError). Additionally, the DVFS dot output is disabled by
default for speed purposes.
Minor fixup for 0aeca8f.
The following patches had unexpected interactions with the current
upstream code and have been reverted for now:
e07fd01651f3: power: Add support for power models
831c7f2f9e39: power: Low-power idle power state for idle CPUs
4f749e00b667: power: Add power states to ClockedObject
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
--HG--
extra : amend_source : 0b6fb073c6bbc24be533ec431eb51fbf1b269508
In general, the ThreadID parameter is unnecessary in the memory system
as the ContextID is what is used for the purposes of locks/wakeups.
Since we allocate sequential ContextIDs for each thread on MT-enabled
CPUs, ThreadID is unnecessary as the CPUs can identify the requesting
thread through sideband info (SenderState / LSQ entries) or ContextID
offset from the base ContextID for a cpu.
This patch adds a configurable indirect branch predictor that can be indexed
by a combination of GHR and path history hashes. Implements the functionality
described in:
"Target prediction for indirect jumps" by Chang, Hao, and Patt
http://dl.acm.org/citation.cfm?id=264209
The extant BTB code doesn't hash on the thread id but does check the
thread id for 'btb hits'. This results in 1-thread of a multi-threaded
workload taking a BTB entry, and all other threads missing for the same branch
missing.
This patch adds some basic support for power models in gem5.
The power interface is defined so it can interact with thermal
models as well. It implements a simple power evaluator that
can be used for simple power models that express power in the
form of a math expression. These expressions can use stats
within the same SimObject (or down its hierarchy) and some
magic variables such as "temp" for temperature.
In future patches we will extend this functionality to allow
slightly more complex expressions.
The model allows it to be extended to use other kinds of models.
Finally, the thermal model is updated to use the power usage as input.
Add 4 power states to the ClockedObject, provides necessary access functions
to check and update the power state. Default power state is UNDEFINED, it is
responsibility of the respective simulation model to provide the startup state
and any other logic for state change.
Add number of transition stat.
Add distribution of time spent in clock gated state.
Add power state residency stat.
Add dump call back function to allow stats update of distribution and residency
stats.
This patch enables Linux to read the temperature using hwmon infrastructure.
In order to use this in your gem5 you need to compile the kernel using the
following configs:
CONFIG_HWMON=y
CONFIG_SENSORS_VEXPRESS=y
And a proper dts file (containing an entry such as):
dcc {
compatible = "arm,vexpress,config-bus";
arm,vexpress,config-bridge = <&v2m_sysreg>;
temp@0 {
compatible = "arm,vexpress-temp";
arm,vexpress-sysreg,func = <4 0>;
label = "DCC";
};
};
This patch adds basic thermal support to gem5. It models energy dissipation
through a circuital equivalent, which allows us to use RC networks.
This lays down the basic infrastructure to do so, but it does not "work" due
to the lack of power models. For now some hardcoded number is used as a PoC.
The solver is embedded in the patch.
