Commit graph

1487 commits

Author SHA1 Message Date
Andreas Hansson
82397921a5 mem: Check for waiting state in bus draining
This patch fixes a bug in the bus where the bus transitions from busy
to idle and still has a port that is waiting for a retry from a peer.
2013-05-30 12:53:57 -04:00
Andreas Hansson
bf6291460d mem: Add a LPDDR3-1600 configuration
This patch adds a typical (leaning towards fast) LPDDR3 configuration
based on publically available data. As expected, it looks very similar
to the LPDDR2-S4 configuration, only with a slightly lower burst time.
2013-05-30 12:53:56 -04:00
Andreas Hansson
ce1ad84abd mem: Adapt the LPDDR2 to match a single x32 channel
This patch adapts the existing LPDDR2 configuration to make use of the
multi-channel functionality. Thus, to get a x64 interface two
controllers should be instantiated using the makeMultiChannel method.

The page size and ranks are also adapted to better suit with a typical
LPDDR2 part.
2013-05-30 12:53:55 -04:00
Andreas Hansson
88aa7755f4 mem: Avoid explicitly zeroing the memory backing store
This patch removes the explicit memset as it is redundant and causes
the simulator to touch the entire space, forcing the host system to
allocate the pages.

Anonymous pages are mapped on the first access, and the page-fault
handler is responsible for zeroing them. Thus, the pages are still
zeroed, but we avoid touching the entire allocated space which enables
us to use much larger memory sizes as long as not all the memory is
actually used.
2013-05-30 12:53:54 -04:00
Malek Musleh
64af621cc6 ruby: slicc: fix error msg in TypeFieldMemberAST.py 2013-05-21 11:57:14 -05:00
Nilay Vaish
4ef466cc8a ruby: moesi hammer: cosmetic changes
Updates copyright years, removes space at the end of lines, shortens
variable names.
2013-05-21 11:32:45 -05:00
Nilay Vaish
09d5bc7e6f ruby: mesi cmp directory: cosmetic changes
Updates copyright years, removes space at the end of lines, shortens
variable names.
2013-05-21 11:32:38 -05:00
Nilay Vaish
bd3d1955da ruby: moesi cmp token: cosmetic changes
Updates copyright years, removes space at the end of lines, shortens
variable names.
2013-05-21 11:32:24 -05:00
Nilay Vaish
e7ce518168 ruby: moesi cmp directory: cosmetic changes
Updates copyright years, removes space at the end of lines, shortens
variable names.
2013-05-21 11:32:15 -05:00
Nilay Vaish ext:(%2C%20Malek%20Musleh%20%3Cmalek.musleh%40gmail.com%3E)
59a7abff29 ruby: add stats to .sm files, remove cache profiler
This patch changes the way cache statistics are collected in ruby.

As of now, there is separate entity called CacheProfiler which holds
statistical variables for caches. The CacheMemory class defines different
functions for accessing the CacheProfiler. These functions are then invoked
in the .sm files. I find this approach opaque and prone to error. Secondly,
we probably should not be paying the cost of a function call for recording
statistics.

Instead, this patch allows for accessing statistical variables in the
.sm files. The collection would become transparent. Secondly, it would happen
in place, so no function calls. The patch also removes the CacheProfiler class.

--HG--
rename : src/mem/slicc/ast/InfixOperatorExprAST.py => src/mem/slicc/ast/OperatorExprAST.py
2013-05-21 11:31:31 -05:00
Mitch Hayenga
b222ba2fd3 sim: Fix two bugs relating to software caching of PageTable entries.
The existing implementation can read uninitialized data or stale information
from the cached PageTable entries.

1) Add a valid bit for the cache entries.  Simply using zero for the virtual
address to signify invalid entries is not sufficient.  Speculative, wrong-path
accesses frequently access page zero.  The current implementation would return
a uninitialized TLB entry when address zero was accessed and the PageTable
cache entry was invalid.

2) When unmapping/mapping/remaping a page, invalidate the corresponding
PageTable cache entry if one already exists.
2013-04-23 09:47:52 -04:00
Nilay Vaish
95eebf9e5e ruby: mesi coherence protocol: remove unused state M_MB 2013-04-23 00:03:07 -05:00
Nilay Vaish
aa86800e7a ruby: patch checkpoint restore with garnet
Due to recent changes to clocking system in Ruby and the way Ruby restores
state from a checkpoint, garnet was failing to run from a checkpointed state.
The problem is that Ruby resets the time to zero while warming up the caches.
If any component records a local copy of the time (read calls curCycle())
before the simulation has started, then that component will not operate until
that time is reached. In the context of this particular patch, the Garnet
Network class calls curCycle() at multiple places. Any non-operational
component can block in requests in the memory system, which the system
interprets as a deadlock. This patch makes changes so that Garnet can
successfully run from checkpointed state.

It adds a globally visible time at which the actual execution started. This
time is initialized in RubySystem::startup() function. This variable is only
meant for components with in Ruby. This replaces the private variable that
was maintained within Garnet since it is not possible to figure out the
correct time when the value of this variable can be set.

The patch also does away with all cases where curCycle() is called with in
some Ruby component before the system has actually started executing. This
is required due to the quirky manner in which ruby restores from a checkpoint.
2013-04-23 00:03:02 -05:00
Andreas Hansson
e23e3bea8b mem: Address mapping with fine-grained channel interleaving
This patch adds an address mapping scheme where the channel
interleaving takes place on a cache line granularity. It is similar to
the existing RaBaChCo that interleaves on a DRAM page, but should give
higher performance when there is less locality in the address
stream.
2013-04-22 13:20:34 -04:00
Andreas Hansson
e61799aa7c mem: More descriptive enum names for address mapping
This patch changes the slightly ambigious names used for the address
mapping scheme to be more descriptive, and actually spell out what
they do. With this patch we also open up for adding more flavours of
open- and close-type mappings, i.e. interleaving across channels with
the open map.
2013-04-22 13:20:33 -04:00
Andreas Hansson
a35d3ff167 mem: Add a WideIO DRAM configuration
This patch adds a WideIO 200 MHz configuration that can be used as a
baseline to compare with DDRx and LPDDRx. Note that it is a single
channel and that it should be replicated 4 times. It is based on
publically available information and attempts to capture an envisioned
8 Gbit single-die part (i.e. without TSVs).
2013-04-22 13:20:33 -04:00
Uri Wiener
a8fbfefb5e mem: Adding verbose debug output in the memory system
This patch provides useful printouts throughut the memory system. This
includes pretty-printed cache tags and function call messages
(call-stack like).
2013-04-22 13:20:33 -04:00
Andreas Hansson
9929e884b6 mem: Replace check with panic where inhibited should not happen
This patch changes the SimpleTimingPort and RubyPort to panic on
inhibited requests as this should never happen in either of the
cases. The SimpleTimingPort is only used for the I/O devices PIO port
and the DMA devices config port and should thus never see an inhibited
request. Similarly, the SimpleTimingPort is also used for the
MessagePort in x86, and there should also not be any cases where the
port sees an inhibited request.
2013-04-22 13:20:33 -04:00
Dam Sunwoo
e8381142b0 sim: separate nextCycle() and clockEdge() in clockedObjects
Previously, nextCycle() could return the *current* cycle if the current tick was
already aligned with the clock edge. This behavior is not only confusing (not
quite what the function name implies), but also caused problems in the
drainResume() function. When exiting/re-entering the sim loop (e.g., to take
checkpoints), the CPUs will drain and resume. Due to the previous behavior of
nextCycle(), the CPU tick events were being rescheduled in the same ticks that
were already processed before draining. This caused divergence from runs that
did not exit/re-entered the sim loop. (Initially a cycle difference, but a
significant impact later on.)

This patch separates out the two behaviors (nextCycle() and clockEdge()),
uses nextCycle() in drainResume, and uses clockEdge() everywhere else.
Nothing (other than name) should change except for the drainResume timing.
2013-04-22 13:20:31 -04:00
Nilay Vaish
03c60f005e ruby: moesi cmp directory: add copyright notice 2013-04-17 16:06:58 -05:00
Joel Hestness
1583056de8 Ruby: Fix RubyPort evict packet memory leak
When using the o3 or inorder CPUs with many Ruby protocols, the caches may
need to forward invalidations to the CPUs. The RubyPort was instantiating a
packet to be sent to the CPUs to signal the eviction, but the packets were
not being freed by the CPUs. Consistent with the classic memory model, stack
allocate the packet and heap allocate the request so on
ruby_eviction_callback() completion, the packet deconstructor is called, and
deletes the request (*Note: stack allocating the request causes double
deletion, since it will be deleted in the packet destructor). This results in
the least memory allocations without memory errors.
2013-04-09 16:25:30 -05:00
Joel Hestness
46d4b71aa2 Ruby: Delete packet requests during warmup
When warming up caches in Ruby, the CacheRecorder sends fetch requests into
Ruby Sequencers with packet types that require responses. Since responses are
never generated for these CacheRecorder requests, the requests are not deleted
in the packet destructor called from the Ruby hit callback. Free the request.
2013-04-09 16:25:29 -05:00
Joel Hestness
e98c3c227d Ruby: Add field to slicc machine for generic type
This allows you to have (i.e.) an L2 cache that is not named "L2Cache"
but is still a GenericMachineType_L2Cache. This is particularly
helpful if the protocol has multiple L2 controllers.
2013-04-09 16:25:29 -05:00
Joel Hestness
b936619ab4 Ruby: Order profilers based on version
When Ruby stats are printed for events and transitions, they include stats
for all of the controllers of the same type, but they are not necessarily
printed in order of the controller ID "version", because of the way the
profilers were added to the profiler vector. This patch fixes the push order
problem so that the stats are printed in ascending order 0->(# controllers),
so statistics parsers may correctly assume the controller to which the stats
belong.
2013-04-09 16:25:29 -05:00
Jason Power
88d34665d0 Ruby: More descriptive message buffer connection fatal
When connecting message buffers between Ruby controllers, it is
easy to mistakenly connect multiple controllers to the same message
buffer. This patch prints a more descriptive fatal message than the
previous assert statement in order to facilitate easier debugging.
2013-04-09 16:15:06 -05:00
Jason Power
19cc9fc6bd Ruby: Fix typo in Slicc if-statement AST error
The error in the SLICC code was hidden by the python error in SLICC parser
before this patch
2013-04-09 16:12:42 -05:00
Joel Hestness
3b02210713 Ruby System, Cache Recorder: Use delete [] for trace vars
The cache trace variables are array allocated uint8_t* in the RubySystem and
the Ruby CacheRecorder, but the code used delete to free the memory, resulting
in Valgrind memory errors. Change these deletes to delete [] to get rid of the
errors.
2013-04-07 20:31:15 -05:00
Mitch Hayenga
4920f0d7e5 mem: Fix cache latency bug
Fixes a latency calculation bug for accesses during a cache line fill.

Under a cache miss, before the line is filled, accesses to the cache are
associated with a MSHR and marked as targets.  Once the line fill completes,
MSHR target packets pay an additional latency of
"responseLatency + busSerializationLatency".  However, the "whenReady"
field of the cache line is only set to an additional delay of
"busSerializationLatency".  This lacks the responseLatency component of
the fill.  It is possible for accesses that occur on the cycle of
(or briefly after) the line fill to respond without properly paying the
responseLatency.  This also creates the situation where two accesses to the
same address may be serviced in an order opposite of how they were received
by the cache.  For stores to the same address, this means that although the
cache performs the stores in the order they were received, acknowledgements
may be sent in a different order.

Adding the responseLatency component to the whenReady field preserves the
penalty that should be paid and prevents these ordering issues.

Committed by: Nilay Vaish <nilay@cs.wisc.edu>
2013-03-27 18:36:09 -05:00
Rene de Jong
87089175cc mem: Cancel cache retry event when blocking port
This patch solves the corner case scenario where the sendRetryEvent could be
scheduled twice, when an io device stresses the IOcache in the system. This
should not be possible in the cache system.
2013-03-26 14:46:51 -04:00
Andreas Hansson
93a8423dea mem: Separate waiting for the bus and waiting for a peer
This patch splits the retryList into a list of ports that are waiting
for the bus itself to become available, and a map that tracks the
ports where forwarding failed due to a peer not accepting the
packet. Thus, when a retry reaches the bus, it can be sent to the
appropriate port that initiated that transaction.

As a consequence of this patch, only ports that are really ready to go
will get a retry, thus reducing the amount of redundant failed
attempts. This patch also makes it easier to reason about the order of
servicing requests as the ports waiting for the bus are now clearly
FIFO and much easier to change if desired.
2013-03-26 14:46:47 -04:00
Andreas Hansson
362f6f1a16 mem: Introduce a variable for the retrying port
This patch introduces a variable to keep track of the retrying port
instead of relying on it being the front of the retryList.

Besides the improvement in readability, this patch is a step towards
separating out the two cases where a port is waiting for the bus to be
free, and where the forwarding did not succeed and the bus is waiting
for a retry to pass on to the original initiator of the transaction.

The changes made are currently such that the regressions are not
affected. This is ensured by always prioritizing the currently
retrying port and putting it back at the front of the retry list.
2013-03-26 14:46:46 -04:00
Andreas Hansson
7a57b1bce0 mem: Add optional request flags to the packet trace
This patch adds an optional flags field to the packet trace to encode
the request flags that contain information about whether the request
is (un)cacheable, instruction fetch, preftech etc.
2013-03-26 14:46:44 -04:00
Nilay Vaish
b2c8c50f17 ruby: slicc: set sender, receiver clock objs for optional queue 2013-03-22 17:21:23 -05:00
Nilay Vaish
e85b556d70 ruby: message buffer: correct previous errors
A recent set of patches added support for multiple clock domains to ruby.
I had made some errors while writing those patches. The sender was using
the receiver side clock while enqueuing a message in the buffer. Those
errors became visible while creating (or restoring from) checkpoints. The
errors also become visible when a multi eventq scenario occurs.
2013-03-22 17:21:22 -05:00
Nilay Vaish
47c8cb72fc ruby: message buffer: remove _ptr from some variables
The names were getting too long.
2013-03-22 15:53:27 -05:00
Nilay Vaish
6465cf5824 ruby: message buffer node: used Tick in place of Cycles
The message buffer node used to keep time in terms of Cycles. Since the
sender and the receiver can have different clock periods, storing node
time in cycles requires some conversion. Instead store the time directly
in Ticks.
2013-03-22 15:53:26 -05:00
Nilay Vaish
39e9445468 ruby: consumer: avoid using receiver side clock
A set of patches was recently committed to allow multiple clock domains
in ruby. In those patches, I had inadvertently made an incorrect use of
the clocks. Suppose object A needs to schedule an event on object B. It
was possible that A accesses B's clock to schedule the event. This is not
possible in actual system. Hence, changes are being to the Consumer class
so as to avoid such happenings. Note that in a multi eventq simulation,
this can possibly lead to an incorrect simulation.

There are two functions in the Consumer class that are used for scheduling
events. The first function takes in the relative delay over the current time
as the argument and adds the current time to it for scheduling the event.
The second function takes in the absolute time (in ticks) for scheduling the
event. The first function is now being moved to protected section of the
class so that only objects of the derived classes can use it. All other
objects will have to specify absolute time while scheduling an event
for some consumer.
2013-03-22 15:53:26 -05:00
Nilay Vaish
28005a7626 ruby: remove unsued profile functions 2013-03-22 15:53:25 -05:00
Nilay Vaish
89bb826079 ruby: keep histogram of outstanding requests in seq
The histogram for tracking outstanding counts per cycle is maintained
in the profiler. For a parallel implementation of the memory system, we
need that this histogram is maintained locally. Hence it will now be
kept in the sequencer itself. The resulting histograms will be merged
when the stats are printed.
2013-03-22 15:53:25 -05:00
Nilay Vaish
870d545788 slicc: remove check if the L1Cache has a sequencer 2013-03-22 15:53:24 -05:00
Nilay Vaish
8573a69d8f ruby: move stall and wakeup functions to AbstractController
These functions are currently implemented in one of the files related to Slicc.
Since these are purely C++ functions, they are better suited to be in the base
class.
2013-03-22 15:53:24 -05:00
Nilay Vaish
eccc86e809 ruby: connect two controllers using only message buffers
This patch modifies ruby so that two controllers can be connected to each
other with only message buffers in between. Before this patch, all the
controllers had to be connected to the network  for them to communicate
with each other. With this patch, one can have protocols where a controller
is not connected to the network, but communicates with another controller
through a message buffer.
2013-03-22 15:53:23 -05:00
Nilay Vaish
5aa43e130a ruby: convert Topology to regular class
The Topology class in Ruby does not need to inherit from SimObject class.
This patch turns it into a regular class. The topology object is now created
in the constructor of the Network class. All the parameters for the topology
class have been moved to the network class.
2013-03-22 15:53:23 -05:00
Nilay Vaish
2d50127642 ruby: network: move routers from topology to network 2013-03-22 15:53:22 -05:00
Andreas Hansson
c01c5e971b mem: Fix missing delete of packet in DRAM access
This patch fixes a memory leak caused by not deleting packets that
require no response.
2013-03-18 05:22:45 -04:00
Nilay Vaish
dc37b03439 ruby: set: corrects csprintf() call introduced by 7d95b650c9b6 2013-03-15 16:28:08 -05:00
Andreas Hansson
92e973b310 ruby: Fix gcc 4.8 maybe-uninitialized compilation error
This patch fixes the one-and-only gcc 4.8 compilation error, being a
warning about "maybe uninitialized" in Orion.
2013-03-07 05:55:02 -05:00
Nilay Vaish
c061819890 ruby: remove the functional copy of memory in se mode
This patch removes the functional copy of the memory that was maintained in
the se mode. Now ruby itself will provide the data.
2013-03-06 21:53:57 -06:00
Nilay Vaish
e8802fa127 ruby: garnet: fixed: implement functional access 2013-03-06 21:53:16 -06:00
Blake Hechtman ext:(%2C%20Nilay%20Vaish%20%3Cnilay%40cs.wisc.edu%3E)
af8eb67fb4 ruby: fixes functional writes to RubyRequest
The functional write code was assuming that all writes are block sized,
which may not be true for Ruby Requests. This bug can lead to a buffer
overflow.

Committed by: Nilay Vaish <nilay@cs.wisc.edu>
2013-03-02 23:12:55 -06:00
Andreas Hansson
e5bcb30756 mem: Add check if SimpleDRAM nextReqEvent is scheduled
This check covers a case where a retry is called from the SimpleDRAM
causing a new request to appear before the DRAM itself schedules a
nextReqEvent. By adding this check, the event is not scheduled twice.
2013-03-01 13:20:33 -05:00
Andreas Hansson
da5356ccce mem: Add a method to build multi-channel DRAM configurations
This patch adds a class method that allows easy creation of
channel-interleaved multi-channel DRAM configurations. It is enabled
by a class method to allow customisation of the class independent of
the channel configuration. For example, the user can create a MyDDR
subclass of e.g. SimpleDDR3, and then create a four-channel
configuration of the subclass by calling MyDDR.makeMultiChannel(4,
mem_start, mem_size).
2013-03-01 13:20:32 -05:00
Andreas Hansson
0facc8e1ac mem: SimpleDRAM variable naming and whitespace fixes
This patch fixes a number of small cosmetic issues in the SimpleDRAM
module. The most important change is to move the accounting of
received packets to after the check is made if the packet should be
retried or not. Thus, packets are only counted if they are actually
accepted.
2013-03-01 13:20:24 -05:00
Andreas Hansson
3ba131f4d5 mem: Add support for multi-channel DRAM configurations
This patch adds support for multi-channel instances of the DRAM
controller model by stripping away the channel bits in the address
decoding. The patch relies on the availiability of address
interleaving and, at this time, it is up to the user to configure the
interleaving appropriately. At the moment it is assumed that the
channel interleaving bits are immediately following the column bits
(smallest sensible interleaving). Convenience methods for building
multi-channel configurations will be added later.
2013-03-01 13:20:22 -05:00
Andreas Hansson
1a58362e25 mem: Merge interleaved ranges when creating backing store
This patch adds merging of interleaved ranges before creating the
backing stores. The backing stores are always a contigous chunk of the
address space, and with this patch it is possible to have interleaved
memories in the system.
2013-03-01 13:20:21 -05:00
Andreas Hansson
cafd38f36c mem: Merge ranges in bus before passing them on
This patch adds basic merging of address ranges to the bus, such that
interleaved ranges are merged together before being passed on by the
bus. As such, the bus aggregates the address ranges of the connected
slave ports and then passes on the merged ranges through its master
ports. The bus thus hides the complexity of the interleaved ranges and
only exposes contigous ranges to the surrounding system.

As part of this patch, the bus ranges are also cached for any future
queries.
2013-03-01 13:20:19 -05:00
Dibakar Gope ext:(%2C%20Nilay%20Vaish%20%3Cnilay%40cs.wisc.edu%3E)
c636a09e83 ruby: mesi coherence protocol: invalidate lock
The MESI CMP directory coherence protocol, while transitioning from SM to IM,
did not invalidate the lock that it might have taken on a cache line. This
patch adds an action for doing so.

The problem was found by Dibakar, but I was not happy with his proposed
solution. So I implemented a different solution.

Committed by: Nilay Vaish <nilay@cs.wisc.edu>
2013-02-28 10:04:26 -06:00
Nilay Vaish
fea27bc49b slicc: remove unused variable message_buffer_names 2013-02-19 22:58:51 -06:00
Nilay Vaish
e95e78ff2f ruby: remove unused variable m_print_config in class Topology 2013-02-19 22:58:50 -06:00
Andreas Hansson
da950caed2 mem: Fix sender state bug and delay popping
This patch fixes a newly introduced bug where the sender state was
popped before checking that it should be. Amazingly all regressions
pass, but Linux fails to boot on the detailed CPU with caches enabled.
2013-02-19 12:57:47 -05:00
Andreas Hansson
a62afd094b scons: Fix warnings issued by clang 3.2svn (XCode 4.6)
This patch fixes the warnings that clang3.2svn emit due to the "-Wall"
flag. There is one case of an uninitialised value in the ARM neon ISA
description, and then a whole range of unused private fields that are
pruned.
2013-02-19 05:56:08 -05:00
Andreas Hansson
319443d42d scons: Add warning for missing declarations
This patch enables warnings for missing declarations. To avoid issues
with SWIG-generated code, the warning is only applied to non-SWIG
code.
2013-02-19 05:56:07 -05:00
Andreas Hansson
c10098f28b scons: Fix up numerous warnings about name shadowing
This patch address the most important name shadowing warnings (as
produced when using gcc/clang with -Wshadow). There are many
locations where constructor parameters and function parameters shadow
local variables, but these are left unchanged.
2013-02-19 05:56:06 -05:00
Andreas Hansson
860155a5fc mem: Enforce strict use of busFirst- and busLastWordTime
This patch adds a check to ensure that the delay incurred by
the bus is not simply disregarded, but accounted for by someone. At
this point, all the modules do is to zero it out, and no additional
time is spent. This highlights where the bus timing is simply dropped
instead of being paid for.

As a follow up, the locations identified in this patch should add this
additional time to the packets in one way or another. For now it
simply acts as a sanity check and highlights where the delay is simply
ignored.

Since no time is added, all regressions remain the same.
2013-02-19 05:56:06 -05:00
Andreas Hansson
40d0e6c899 mem: Change accessor function names to match the port interface
This patch changes the names of the cache accessor functions to be in
line with those used by the ports. This is done to avoid confusion and
get closer to a one-to-one correspondence between the interface of the
memory object (the cache in this case) and the port itself.

The member function timingAccess has been split into a snoop/non-snoop
part to avoid branching on the isResponse() of the packet.
2013-02-19 05:56:06 -05:00
Andreas Hansson
b3fc8839c4 mem: Make packet bus-related time accounting relative
This patch changes the bus-related time accounting done in the packet
to be relative. Besides making it easier to align the cache timing to
cache clock cycles, it also makes it possible to create a Last-Level
Cache (LLC) directly to a memory controller without a bus inbetween.

The bus is unique in that it does not ever make the packets wait to
reflect the time spent forwarding them. Instead, the cache is
currently responsible for making the packets wait. Thus, the bus
annotates the packets with the time needed for the first word to
appear, and also the last word. The cache then delays the packets in
its queues before passing them on. It is worth noting that every
object attached to a bus (devices, memories, bridges, etc) should be
doing this if we opt for keeping this way of accounting for the bus
timing.
2013-02-19 05:56:06 -05:00
Andreas Hansson
362160c8ae mem: Add deferred packet class to prefetcher
This patch removes the time field from the packet as it was only used
by the preftecher. Similar to the packet queue, the prefetcher now
wraps the packet in a deferred packet, which also has a tick
representing the absolute time when the packet should be sent.
2013-02-19 05:56:06 -05:00
Andreas Hansson
7cd49b24d2 sim: Make clock private and access using clockPeriod()
This patch makes the clock member private to the ClockedObject and
forces all children to access it using clockPeriod(). This makes it
impossible to inadvertently change the clock, and also makes it easier
to transition to a situation where the clock is derived from e.g. a
clock domain, or through a multiplier.
2013-02-19 05:56:06 -05:00
Sascha Bischoff
86a4d09269 mem: Fix SenderState related cache deadlock
This patch fixes a potential deadlock in the caches. This deadlock
could occur when more than one cache is used in a system, and
pkt->senderState is modified in between the two caches. This happened
as the caches relied on the senderState remaining unchanged, and used
it for instantaneous upstream communication with other caches.

This issue has been addressed by iterating over the linked list of
senderStates until we are either able to cast to a MSHR* or
senderState is NULL. If the cast is successful, we know that the
packet has previously passed through another cache, and therefore
update the downstreamPending flag accordingly. Otherwise, we do
nothing.
2013-02-19 05:56:06 -05:00
Andreas Hansson
0622f30961 mem: Add predecessor to SenderState base class
This patch adds a predecessor field to the SenderState base class to
make the process of linking them up more uniform, and enable a
traversal of the stack without knowing the specific type of the
subclasses.

There are a number of simplifications done as part of changing the
SenderState, particularly in the RubyTest.
2013-02-19 05:56:05 -05:00
Andreas Hansson
9947923c60 mem: Ensure trace captures packet fields before forwarding
This patch fixes a bug in the CommMonitor caused by the packet being
modified before it is captured in the trace. By recording the fields
before passing the packet on, and then putting these values in the
trace we ensure that even if the packet is modified the trace captures
what the CommMonitor saw.
2013-02-19 05:56:05 -05:00
Andreas Hansson
f6550b3d20 mem: Tighten up cache constness and scoping
This patch merely adopts a more strict use of const for the cache
member functions and variables, and also moves a large portion of the
member functions from public to protected.
2013-02-15 17:40:10 -05:00
Andreas Sandberg
b904bd5437 sim: Add a system-global option to bypass caches
Virtualized CPUs and the fastmem mode of the atomic CPU require direct
access to physical memory. We currently require caches to be disabled
when using them to prevent chaos. This is not ideal when switching
between hardware virutalized CPUs and other CPU models as it would
require a configuration change on each switch. This changeset
introduces a new version of the atomic memory mode,
'atomic_noncaching', where memory accesses are inserted into the
memory system as atomic accesses, but bypass caches.

To make memory mode tests cleaner, the following methods are added to
the System class:

 * isAtomicMode() -- True if the memory mode is 'atomic' or 'direct'.
 * isTimingMode() -- True if the memory mode is 'timing'.
 * bypassCaches() -- True if caches should be bypassed.

The old getMemoryMode() and setMemoryMode() methods should never be
used from the C++ world anymore.
2013-02-15 17:40:09 -05:00
Andreas Hansson
7c6bc52bf5 Ruby: Fix compilation errors on gcc 4.7 and clang 3.2
This patch fixes a few (recently added) errors that prevented gem5 from
compiling on more recent versions of gcc and clang.
2013-02-14 12:24:51 -05:00
Nilay Vaish
71c27e6370 ruby: MI protocol: add a missing transition
The transition for state MII and event Store was found missing during testing.
The transition is being added. The controller will not stall the Store request
in state MII
2013-02-10 21:43:18 -06:00
Nilay Vaish
cb7782f78d ruby: enable multiple clock domains
This patch allows ruby to have multiple clock domains. As I understand
with this patch, controllers can have different frequencies. The entire
network needs to run at a single frequency.

The idea is that with in an object, time is treated in terms of cycles.
But the messages that are passed from one entity to another should contain
the time in Ticks. As of now, this is only true for the message buffers,
but not for the links in the network. As I understand the code, all the
entities in different networks (simple, garnet-fixed, garnet-flexible) should
be clocked at the same frequency.

Another problem is that the directory controller has to operate at the same
frequency as the ruby system. This is because the memory controller does
not make use of the Message Buffer, and instead implements a buffer of its
own. So, it has no idea of the frequency at which the directory controller
is operating and uses ruby system's frequency for scheduling events.
2013-02-10 21:43:17 -06:00
Nilay Vaish
253e8edf13 ruby: replace Time with Cycles (final patch in the series)
This patch is as of now the final patch in the series of patches that replace
Time with Cycles.This patch further replaces Time with Cycles in Sequencer,
Profiler, different protocols and related entities.

Though Time has not been completely removed, the places where it is in use
seem benign as of now.
2013-02-10 21:43:10 -06:00
Nilay Vaish
f6e3ab7bd4 ruby: replace Time with Cycles in garnet fixed and flexible 2013-02-10 21:43:09 -06:00
Nilay Vaish
9d6d6c6718 ruby: replace Time with Tick in replacement policy classes 2013-02-10 21:43:08 -06:00
Nilay Vaish
221d39284e ruby: convert block size, memory size to unsigned 2013-02-10 21:43:07 -06:00
Nilay Vaish
5e33045a2a ruby: replace Time with Cycles in MessageBuffer 2013-02-10 21:26:26 -06:00
Nilay Vaish
b742081cc1 ruby: replace Time with Cycles in Memory Controller 2013-02-10 21:26:25 -06:00
Nilay Vaish
89f86dbd28 ruby: Replace Time with Cycles in SequencerMessage 2013-02-10 21:26:25 -06:00
Nilay Vaish
7862478eef ruby: replace Time with Cycles in Message class
Concomitant changes are being committed as well, including the io operator<<
for the Cycles class.
2013-02-10 21:26:24 -06:00
Nilay Vaish
d3aebe1f91 ruby: replaces Time with Cycles in many places
The patch started of with replacing Time with Cycles in the Consumer class.
But to get ruby to compile, the rest of the changes had to be carried out.
Subsequent patches will further this process, till we completely replace
Time with Cycles.
2013-02-10 21:26:24 -06:00
Nilay Vaish
bc1daae7fd ruby: modifies histogram add() function
This patch modifies the Histogram class' add() function so that it can add
linear histograms as well. The function assumes that the left end point of
the ranges of the two histograms are the same. It also assumes that when
the ranges of the two histogram are changed to accomodate an element not in
the range, the factor used in changing the range is same for both the
histograms.

This function is then used in removing one of the calls to the global
profiler*. The histograms for recording the delays incurred in processing
different requests are now maintained by the controllers. The profiler
adds these histograms when it needs to print the stats.
2013-02-10 21:26:22 -06:00
Nilay Vaish
a49b1df3f0 ruby: record fully busy cycle with in the controller
This patch does several things. First, the counter for fully busy cycles for a
controller is now kept with in the controller, instead of being part of the profiler.
Second, the topology class no longer keeps an array of controllers which was only
used for printing stats. Instead, ruby system will now ask each controller to print
the stats. Thirdly, the statistical variable for recording how many different types
were created is being moved in to the controller from the profiler. Note that for
printing, the profiler will collate results from different controllers.
2013-02-10 21:26:22 -06:00
Nilay Vaish
6aed4d4f93 ruby: correct computation of number of bits required for address
The number of bits required for an address was set to floorLog2(memory size).
This is correct under the assumption that the memory size is a power of 2,
which is not always true. Hence, floorLog2 is being replaced with ceilLog2.
2013-01-31 09:44:20 -06:00
Andreas Hansson
a4288dabf9 mem: Add comments for the DRAM address decoding
This patch adds more verbose comments to explain the two different
address mapping schemes of the DRAM controller.
2013-01-31 07:49:18 -05:00
Andreas Hansson
c4898b15bc mem: Add DDR3 and LPDDR2 DRAM controller configurations
This patch moves the default DRAM parameters from the SimpleDRAM class
to two different subclasses, one for DDR3 and one for LPDDR2. More can
be added as we go forward.

The regressions that previously used the SimpleDRAM are now using
SimpleDDR3 as this is the most similar configuration.
2013-01-31 07:49:14 -05:00
Ani Udipi
eaa37e611f mem: Add tTAW and tFAW to the SimpleDRAM model
This patch adds two additional scheduling constraints to the DRAM
controller model, to constrain the activation rate. The two metrics
are determine the size of the activation window in terms of the number
of activates and the minimum time required for that number of
activates. This maps to current DDRx, LPDDRx and WIOx standards that
have either tFAW (4 activate window) or tTAW (2 activate window)
scheduling constraints.
2013-01-31 07:49:14 -05:00
Andreas Hansson
b7153e2a64 mem: Separate out the different cases for DRAM bus busy time
This patch changes how the data bus busy time is calculated such that
it is delayed to the actual scheduling time of the request as opposed
to being done as soon as possible.

This patch changes a bunch of statistics, and the stats update is
bundled together with the introruction of tFAW/tTAW and the named DRAM
configurations like DDR3 and LPDDR2.
2013-01-31 07:49:13 -05:00
Anthony Gutierrez
af0f8b31db cache: remove drainManager because it's not used
the cache drainManager is set but never cleared, this is because
the cache itself does not need to be drained and thus never
triggers a signalDrainDone(). because the drainManager variable
is not used properly and does not appear to be necessary it has
been removed with this patch.
2013-01-28 20:19:42 -05:00
Nilay Vaish
a8eb5b18e0 ruby: remove get_time()
This patch replaces get_time() in *.sm files with curCycle() which
is now possible since controllers are clocked objects.
2013-01-28 06:14:18 -06:00
Nilay Vaish
31659e83fb ruby: remove call to curCycle in panic()
The panic() function already prints the current tick value. This call to
curCycle() is as such redundant. Since we are trying to move towards multiple
clock domains, this call will print misleading time.
2013-01-28 06:11:42 -06:00
Nilay Vaish
5b6f972750 ruby: remove calls to g_system_ptr->getTime()
This patch further removes calls to g_system_ptr->getTime() where ever other
clocked objects are available for providing current time.
2013-01-17 13:10:12 -06:00
Malek Musleh
1abf950f3c ruby sequencer: converts cycles to ticks in deadlock panic()
This patch converts the panic() print outs in the Sequencer::wakeup()
call from ruby cycles to Ticks(). This makes it easier to debug deadlocks
with the ProtocolTrace flag so the issue time indicated in the panic message
can be quickly searched for.

Committed by: Nilay Vaish <nilay@cs.wisc.edu>
2013-01-14 10:05:12 -06:00
Nilay Vaish
2012983718 Ruby: remove reference to g_system_ptr from class Message
This patch was initiated so as to remove reference to g_system_ptr,
the pointer to Ruby System that is used for getting the current time.
That simple change actual requires changing a lot many things in slicc and
garnet. All these changes are related to how time is handled.

In most of the places, g_system_ptr has been replaced by another clock
object. The changes have been done under the assumption that all the
components in the memory system are on the same clock frequency, but the
actual clocks might be distributed.
2013-01-14 10:05:10 -06:00
Nilay Vaish
cf232de461 Ruby: use ClockedObject in Consumer class
Many Ruby structures inherit from the Consumer, which is used for scheduling
events. The Consumer used to relay on an Event Manager for scheduling events
and on g_system_ptr for time. With this patch, the Consumer will now use a
ClockedObject to schedule events and to query for current time. This resulted
in several structures being converted from SimObjects to ClockedObjects. Also,
the MessageBuffer class now requires a pointer to a ClockedObject so as to
query for time.
2013-01-14 10:04:21 -06:00
Mitch Hayenga
c7dbd5e768 mem: Make LL/SC locks fine grained
The current implementation in gem5 just keeps a list of locks per cacheline.
Due to this, a store to a non-overlapping portion of the cacheline can cause an
LL/SC pair to fail.  This patch simply adds an address range to the lock
structure, so that the lock is only invalidated if the store overlaps the lock
range.
2013-01-08 08:54:07 -05:00
Mitch Hayenga
dc4a0aa2fa mem: Fix use-after-free bug
Running with valgrind I noticed a use after free originating from
simple_mem.cc.  It looks like this is a known issue and this additional call
site was missed in an earlier patch.
2013-01-08 08:54:06 -05:00
Andreas Sandberg
964aa49d15 mem: Fix guest corruption when caches handle uncacheable accesses
When the classic gem5 cache sees an uncacheable memory access, it used
to ignore it or silently drop the cache line in case of a
write. Normally, there shouldn't be any data in the cache belonging to
an uncacheable address range. However, since some architecture models
don't implement cache maintenance instructions, there might be some
dirty data in the cache that is discarded when this happens. The
reason it has mostly worked before is because such cache lines were
most likely evicted by normal memory activity before a TLB flush was
requested by the OS.

Previously, the cache model would invalidate cache lines when they
were accessed by an uncacheable write. This changeset alters this
behavior so all uncacheable memory accesses cause a cache flush with
an associated writeback if necessary. This is implemented by reusing
the cache flushing machinery used when draining the cache, which
implies that writebacks are performed using functional accesses.
2013-01-07 13:05:47 -05:00
Andreas Sandberg
d44f2f611f mem: Remove the IIC replacement policy
The IIC replacement policy seems to be unused and has probably
gathered too much bit rot to be useful. This patch removes the IIC and
its associated cache parameters.
2013-01-07 13:05:39 -05:00
Andreas Hansson
921490a060 sim: Fatal if a clocked object is set to have a clock of 0
This patch adds a check to the clocked object constructor to ensure it
is not configured to have a clock period of 0.
2013-01-07 13:05:39 -05:00
Andreas Hansson
18b147acef mem: Merge ranges that are part of the conf table
This patch adds basic merging of address ranges when determining which
address ranges should be reported in the configuration table. By
performing this merging it is possible to distribute an address range
across many memory channels (controllers). This is essential to enable
address interleaving.
2013-01-07 13:05:38 -05:00
Andreas Hansson
01c5598373 mem: Add interleaving bits to the address ranges
This patch adds support for interleaving bits for the address
ranges. What was previously just a start and end address, now has an
additional three fields, for the high bit, and number of bits to use
for interleaving, and a match value to compare against. If the number
of interleaving bits is set to zero it is effectively disabled.

A number of convenience functions are added to the range to enquire
about the interleaving, its granularity and the number of stripes it
is part of.
2013-01-07 13:05:38 -05:00
Andreas Hansson
e0d93fde99 base: Simplify the AddrRangeMap by removing unused code
This patch cleans up the AddrRangeMap in preparation for the addition
of interleaving by removing unused code. The non-const editions of
find are never used, and hence the duplication is not needed.
2013-01-07 13:05:38 -05:00
Andreas Hansson
15a979c6be mem: Tidy up bus addr range debug messages
This patch tidies up a number of the bus DPRINTFs related to range
manipulation. In particular, it shifts the message about range changes
to the start of the member function, and also adds information about
when all ranges are received.
2013-01-07 13:05:38 -05:00
Andreas Hansson
caf6786ad5 mem: Skip address mapper range checks to allow more flexibility
This patch makes the address mapper less stringent about checking the
before and after ranges, i.e. the original and remapped ranges. The
checks were not really necessary, and there are situations when the
previous checks were too strict.
2013-01-07 13:05:38 -05:00
Andreas Hansson
71da1d2157 base: Encapsulate the underlying fields in AddrRange
This patch makes the start and end address private in a move to
prevent direct manipulation and matching of ranges based on these
fields. This is done so that a transition to ranges with interleaving
support is possible.

As a result of hiding the start and end, a number of member functions
are needed to perform the comparisons and manipulations that
previously took place directly on the members. An accessor function is
provided for the start address, and a function is added to test if an
address is within a range. As a result of the latter the != and ==
operator is also removed in favour of the member function. A member
function that returns a string representation is also created to allow
debug printing.

In general, this patch does not add any functionality, but it does
take us closer to a situation where interleaving (and more cleverness)
can be added under the bonnet without exposing it to the user. More on
that in a later patch.
2013-01-07 13:05:38 -05:00
Andreas Hansson
cfdaf53104 mem: Remove the joining of neighbouring ranges
This patch temporarily removes the joining of ranges when creating the
backing store, to reserve this functionality for the interleaved
ranges that are about to be introduced.

When creating the mmaps for the backing store, there is no point in
creating larger contigous chunks that what is necessary. The larger
chunks will only make life more difficult for the host.

Merging will be re-added later, but then only for interleaved ranges.
2013-01-07 13:05:38 -05:00
Andreas Hansson
f456c7983d mem: Add tracing support in the communication monitor
This patch adds packet tracing to the communication monitor using a
protobuf as the mechanism for creating the trace.

If no file is specified, then the tracing is disabled. If a file is
specified, then for every packet that is successfully sent, a protobuf
message is serialized to the file.
2013-01-07 13:05:37 -05:00
Andreas Hansson
852a7bcf92 mem: Add sanity check to packet queue size
This patch adds a basic check to ensure that the packet queue does not
grow absurdly large. The queue should only be used to store packets
that were delayed due to blocking from the neighbouring port, and not
for actual storage. Thus, a limit of 100 has been chosen for now
(which is already quite substantial).
2013-01-07 13:05:35 -05:00
Andreas Hansson
ce5fc494e3 ruby: Fix missing cxx_header in Switch
This patch addresses a warning related to the swig interface
generation for the Switch class. The cxx_header is now specified
correctly, and the header in question has got a few includes added to
make it all compile.
2013-01-07 13:05:35 -05:00
Andreas Hansson
174269978a mem: Fix a bug in the memory serialization file naming
This patch fixes a bug that caused multiple systems to overwrite each
other physical memory. The system name is now included in the filename
such that this is avoided.
2013-01-07 13:05:35 -05:00
Ali Saidi
9a645d6e9b cache: add note about where conflicts are handled 2013-01-07 13:05:32 -05:00
Nilay Vaish
f3d0be210f ruby: add support for prefetching to MESI protocol 2012-12-11 10:05:56 -06:00
Nilay Vaish
9b72a0f627 ruby: change slicc to allow for constructor args
The patch adds support to slicc for recognizing arguments that should be
passed to the constructor of a class. I did not like the fact that an explicit
check was being carried on the type 'TBETable' to figure out the arguments to
be passed to the constructor.
The patch also moves some of the member variables that are declared for all
the controllers to the base class AbstractController.
2012-12-11 10:05:55 -06:00
Nilay Vaish
93e283abb3 ruby: add a prefetcher
This patch adds a prefetcher for the ruby memory system. The prefetcher
is based on a prefetcher implemented by others (well, I don't know
who wrote the original). The prefetcher does stride-based prefetching,
both unit and non-unit. It obseves the misses in the cache and trains on
these. After the training period is over, the prefetcher starts issuing
prefetch requests to the controller.
2012-12-11 10:05:54 -06:00
Nilay Vaish
d502384795 ruby: add functions for computing next stride/page address 2012-12-11 10:05:53 -06:00
Nilay Vaish
2d6470936c sim: have a curTick per eventq
This patch adds a _curTick variable to an eventq. This variable is updated
whenever an event is serviced in function serviceOne(), or all events upto
a particular time are processed in function serviceEvents(). This change
helps when there are eventqs that do not make use of curTick for scheduling
events.
2012-11-16 10:27:47 -06:00
Nilay Vaish
90c45c29fe ruby: support functional accesses in garnet flexible network 2012-11-10 17:18:01 -06:00
Nilay Vaish
1492ab066d ruby: bug in functionalRead, revert recent changes
Recent changes to functionalRead() in the memory system was not correct.
The change allowed for returning data from the first message found in
the buffers of the memory system. This is not correct since it is possible
that a timing message has data from an older state of the block.

The changes are being reverted.
2012-11-10 17:18:00 -06:00
Andreas Hansson
c4b36901d0 mem: Fix DRAM draining to ensure write queue is empty
This patch fixes the draining of the SimpleDRAM controller model. The
controller performs buffering of writes and normally there is no need
to ever empty the write buffer (if you have a fast on-chip memory,
then use it). The patch adds checks to ensure the write buffer is
drained when the controller is asked to do so.
2012-11-08 04:25:06 -05:00
Hamid Reza Khaleghzadeh ext:(%2C%20Lluc%20Alvarez%20%3Clluc.alvarez%40bsc.es%3E%2C%20Nilay%20Vaish%20%3Cnilay%40cs.wisc.edu%3E)
8cd475d58e ruby: reset and dump stats along with reset of the system
This patch adds support to ruby so that the statistics maintained by ruby
are reset/dumped when the statistics for the rest of the system are
reset/dumped. For resetting the statistics, ruby now provides the
resetStats() function that a sim object can provide. As a consequence, the
clearStats() function has been removed from RubySystem. For dumping stats,
Ruby now adds a callback event to the dumpStatsQueue. The exit callback that
ruby used to add earlier is being removed.

Created by: Hamid Reza Khaleghzadeh.
Improved by: Lluc Alvarez, Nilay Vaish
Committed by: Nilay Vaish
2012-11-02 12:18:25 -05:00
Ali Saidi
ce5766c409 mem: fix use after free issue in memories until 4-phase work complete. 2012-11-02 11:50:16 -05:00
Andreas Sandberg
ddd6af414c mem: Add support for writing back and flushing caches
This patch adds support for the following optional drain methods in
the classical memory system's cache model:

memWriteback() - Write back all dirty cache lines to memory using
functional accesses.

memInvalidate() - Invalidate all cache lines. Dirty cache lines
are lost unless a writeback is requested.

Since memWriteback() is called when checkpointing systems, this patch
adds support for checkpointing systems with caches. The serialization
code now checks whether there are any dirty lines in the cache. If
there are dirty lines in the cache, the checkpoint is flagged as bad
and a warning is printed.
2012-11-02 11:32:02 -05:00
Andreas Sandberg
b81a977e6a sim: Move the draining interface into a separate base class
This patch moves the draining interface from SimObject to a separate
class that can be used by any object needing draining. However,
objects not visible to the Python code (i.e., objects not deriving
from SimObject) still depend on their parents informing them when to
drain. This patch also gets rid of the CountedDrainEvent (which isn't
really an event) and replaces it with a DrainManager.
2012-11-02 11:32:01 -05:00
Andreas Sandberg
c0ab52799c sim: Include object header files in SWIG interfaces
When casting objects in the generated SWIG interfaces, SWIG uses
classical C-style casts ( (Foo *)bar; ). In some cases, this can
degenerate into the equivalent of a reinterpret_cast (mainly if only a
forward declaration of the type is available). This usually works for
most compilers, but it is known to break if multiple inheritance is
used anywhere in the object hierarchy.

This patch introduces the cxx_header attribute to Python SimObject
definitions, which should be used to specify a header to include in
the SWIG interface. The header should include the declaration of the
wrapped object. We currently don't enforce header the use of the
header attribute, but a warning will be generated for objects that do
not use it.
2012-11-02 11:32:01 -05:00
Dam Sunwoo
81406018b0 ARM: dump stats and process info on context switches
This patch enables dumping statistics and Linux process information on
context switch boundaries (__switch_to() calls) that are used for
Streamline integration (a graphical statistics viewer from ARM).
2012-11-02 11:32:01 -05:00
Andreas Hansson
3d98119717 mem: Fix typo in port comments
This patch merely fixes a few typos in the port comments.
2012-10-31 09:28:23 -04:00
Andreas Hansson
6f6adbf0f6 dev: Make default clock more reasonable for system and devices
This patch changes the default system clock from 1THz to 1GHz. This
clock is used by all modules that do not override the default (parent
clock), and primarily affects the IO subsystem. Every DMA device uses
its clock to schedule the next transfer, and the change will thus
cause this inter-transfer delay to be longer.

The default clock of the bus is removed, as the clock inherited from
the system provides exactly the same value.

A follow-on patch will bump the stats.
2012-10-25 13:14:44 -04:00
Nilay Vaish
52d8693677 ruby: functional access updates to network test protocol
I had forgotten to change the network test protocol while making changes to
ruby for supporting functional accesses. This patch updates the protocol so
that it can compile correctly.
2012-10-18 18:35:42 -05:00
Nilay Vaish
5ffc165939 ruby: improved support for functional accesses
This patch adds support to different entities in the ruby memory system
for more reliable functional read/write accesses. Only the simple network
has been augmented as of now. Later on Garnet will also support functional
accesses.
The patch adds functional access code to all the different types of messages
that protocols can send around. These messages are functionally accessed
by going through the buffers maintained by the network entities.
The patch also rectifies some of the bugs found in coherence protocols while
testing the patch.

With this patch applied, functional writes always succeed. But functional
reads can still fail.
2012-10-15 17:51:57 -05:00
Nilay Vaish
61434a9943 ruby: register multiple memory controllers
Currently the Ruby System maintains pointer to only one of the memory
controllers. But there can be multiple controllers in the system. This
patch adds a vector of memory controllers.
2012-10-15 17:27:17 -05:00
Nilay Vaish
c14e6cfc4e ruby: remove AbstractMemOrCache
The only place where this abstract class is in use is the memory controller,
which it self is an abstract class. Does not seem useful at all.
2012-10-15 17:27:16 -05:00
Nilay Vaish
3e607f146f ruby: allow function definition in slicc structs
This patch adds support for function definitions to appear in slicc structs.
This is required for supporting functional accesses for different types of
messages. Subsequent patches will use this to development.
2012-10-15 17:27:16 -05:00
Nilay Vaish
c7b0901b97 ruby banked array: do away with event scheduling
It seems unecessary that the BankedArray class needs to schedule an event
to figure out when the access ends. Instead only the time for the end of access
needs to be tracked.
2012-10-15 17:27:15 -05:00
Nilay Vaish
6a65fafa52 ruby: reset timing after cache warm up
Ruby system was recently converted to a clocked object. Such objects maintain
state related to the time that has passed so far. During the cache warmup, Ruby
system changes its own time and the global time. Later on, the global time is
restored. So Ruby system also needs to reset its own time.
2012-10-15 17:27:15 -05:00
Andreas Hansson
b6bd4f34b4 Mem: Fix incorrect logic in bus blocksize check
This patch fixes the logic in the blocksize check such that the
warning is printed if the size is not 16, 32, 64 or 128.
2012-10-15 12:51:21 -04:00
Andreas Hansson
2a740aa096 Port: Add protocol-agnostic ports in the port hierarchy
This patch adds an additional level of ports in the inheritance
hierarchy, separating out the protocol-specific and protocl-agnostic
parts. All the functionality related to the binding of ports is now
confined to use BaseMaster/BaseSlavePorts, and all the
protocol-specific parts stay in the Master/SlavePort. In the future it
will be possible to add other protocol-specific implementations.

The functions used in the binding of ports, i.e. getMaster/SlavePort
now use the base classes, and the index parameter is updated to use
the PortID typedef with the symbolic InvalidPortID as the default.
2012-10-15 08:12:35 -04:00
Andreas Hansson
9baa35ba80 Mem: Separate the host and guest views of memory backing store
This patch moves all the memory backing store operations from the
independent memory controllers to the global physical memory. The main
reason for this patch is to allow address striping in a future set of
patches, but at this point it already provides some useful
functionality in that it is now possible to change the number of
memory controllers and their address mapping in combination with
checkpointing. Thus, the host and guest view of the memory backing
store are now completely separate.

With this patch, the individual memory controllers are far simpler as
all responsibility for serializing/unserializing is moved to the
physical memory. Currently, the functionality is more or less moved
from AbstractMemory to PhysicalMemory without any major
changes. However, in a future patch the physical memory will also
resolve any ranges that are interleaved and properly assign the
backing store to the memory controllers, and keep the host memory as a
single contigous chunk per address range.

Functionality for future extensions which involve CPU virtualization
also enable the host to get pointers to the backing store.
2012-10-15 08:12:32 -04:00
Andreas Hansson
0c58106b6e Mem: Use deque instead of list for bus retries
This patch changes the data structure used to keep track of ports that
should be told to retry. As the bus is doing this in an FCFS way,
there is no point having a list. A deque is a better match (and is at
least in theory a better choice from a performance point of view).
2012-10-15 08:12:25 -04:00
Andreas Hansson
93a159875a Fix: Address a few minor issues identified by cppcheck
This patch addresses a number of smaller issues identified by the code
inspection utility cppcheck. There are a number of identified leaks in
the arm/linux/system.cc (although the function only get's called once
so it is not a major problem), a few deletes in dev/x86/i8042.cc that
were not array deletes, and sprintfs where the character array had one
element less than needed. In the IIC tags there was a function
allocating an array of longs which is in fact never used.
2012-10-15 08:12:23 -04:00
Andreas Hansson
88554790c3 Mem: Use cycles to express cache-related latencies
This patch changes the cache-related latencies from an absolute time
expressed in Ticks, to a number of cycles that can be scaled with the
clock period of the caches. Ultimately this patch serves to enable
future work that involves dynamic frequency scaling. As an immediate
benefit it also makes it more convenient to specify cache performance
without implicitly assuming a specific CPU core operating frequency.

The stat blocked_cycles that actually counter in ticks is now updated
to count in cycles.

As the timing is now rounded to the clock edges of the cache, there
are some regressions that change. Plenty of them have very minor
changes, whereas some regressions with a short run-time are perturbed
quite significantly. A follow-on patch updates all the statistics for
the regressions.
2012-10-15 08:10:54 -04:00
Andreas Hansson
36d199b9a9 Mem: Use range operations in bus in preparation for striping
This patch transitions the bus to use the AddrRange operations instead
of directly accessing the start and end. The change facilitates the
move to a more elaborate AddrRange class that also supports address
striping in the bus by specifying interleaving bits in the ranges.

Two new functions are added to the AddrRange to determine if two
ranges intersect, and if one is a subset of another. The bus
propagation of address ranges is also tweaked such that an update is
only propagated if the bus received information from all the
downstream slave modules. This avoids the iteration and need for the
cycle-breaking scheme that was previously used.
2012-10-15 08:07:04 -04:00
Andreas Hansson
43ca8415e8 Mem: Determine bus block size during initialisation
This patch moves the block size computation from findBlockSize to
initialisation time, once all the neighbouring ports are connected.

There is no need to dynamically update the block size, and the caching
of the value effectively avoided that anyhow. This is very similar to
what was already in place, just with a slightly leaner implementation.
2012-10-11 06:38:43 -04:00
Nilay Vaish
88ba1c452b ruby: makes some members non-static
This patch makes some of the members (profiler, network, memory vector)
of ruby system non-static.
2012-10-02 14:35:45 -05:00
Nilay Vaish
4488379244 ruby: changes to simple network
This patch makes the Switch structure inherit from BasicRouter, as is
done in two other networks.
2012-10-02 14:35:45 -05:00
Nilay Vaish
b370f6a7b2 ruby: rename template_hack to template
I don't like using the word hack. Hence, the patch.
2012-10-02 14:35:44 -05:00
Nilay Vaish
d58f84c481 ruby: remove unused code in protocols 2012-10-02 14:35:44 -05:00
Nilay Vaish
73eafe4849 ruby: remove some unused things in slicc
This patch removes the parts of slicc that were required for multi-chip
protocols. Going ahead, it seems multi-chip protocols would be implemented
by playing with the network itself.
2012-10-02 14:35:43 -05:00
Nilay Vaish
3c9d3b16d8 ruby: move functional access to ruby system
This patch moves the code for functional accesses to ruby system. This is
because the subsequent patches add support for making functional accesses
to the messages in the interconnect. Making those accesses from the ruby port
would be cumbersome.
2012-10-02 14:35:42 -05:00
Nilay Vaish
95664da097 MI coherence protocol: add copyright notice 2012-09-30 13:20:53 -05:00
Djordje Kovacevic
80a26a3e39 MEM: Put memory system document into doxygen 2012-09-25 11:49:41 -05:00
Mrinmoy Ghosh
6fc0094337 Cache: add a response latency to the caches
In the current caches the hit latency is paid twice on a miss. This patch lets
a configurable response latency be set of the cache for the backward path.
2012-09-25 11:49:41 -05:00
Ali Saidi
396600de10 mem: Add a gasket that allows memory ranges to be re-mapped.
For example if DRAM is at two locations and mirrored this patch allows the
mirroring to occur.
2012-09-25 11:49:40 -05:00
Joel Hestness
4095af5fd6 RubyPort and Sequencer: Fix draining
Fix the drain functionality of the RubyPort to only call drain on child ports
during a system-wide drain process, instead of calling each time that a
ruby_hit_callback is executed.

This fixes the issue of the RubyPort ports being reawakened during the drain
simulation, possibly with work they didn't previously have to complete. If
they have new work, they may call process on the drain event that they had
not registered work for, causing an assertion failure when completing the
drain event.

Also, in RubyPort, set the drainEvent to NULL when there are no events
to be drained. If not set to NULL, the drain loop can result in stale
drainEvents used.
2012-09-23 13:57:08 -05:00
Andreas Hansson
3b6a143ec5 DRAM: Introduce SimpleDRAM to capture a high-level controller
This patch introduces a high-level model of a DRAM controller, with a
basic read/write buffer structure, a selectable and customisable
arbiter, a few address mapping options, and the basic DRAM timing
constraints. The parameters make it possible to turn this model into
any desired DDRx/LPDDRx/WideIOx memory controller.

The intention is not to be cycle accurate or capture every aspect of a
DDR DRAM interface, but rather to enable exploring of the high-level
knobs with a good simulation speed. Thus, contrary to e.g. DRAMSim
this module emphasizes simulation speed with a good-enough accuracy.

This module is merely a starting point, and there are plenty additions
and improvements to come. A notable addition is the support for
address-striping in the bus to enable a multi-channel DRAM
controller. Also note that there are still a few "todo's" in the code
base that will be addressed as we go along.

A follow-up patch will add basic performance regressions that use the
traffic generator to exercise a few well-defined corner cases.
2012-09-21 11:48:13 -04:00
Andreas Hansson
4aee3aa073 Mem: Tidy up bus member variables types
This patch merely tidies up the types used for the bus member
variables. It also makes the constant ones const.
2012-09-21 10:11:24 -04:00
Anthony Gutierrez
9cd0c5ecc8 bus: removed outdated warn regarding 64 B block sizes
this warn is outdated as 64 B blocks are very common, and even
the default size for some CPU types. E.g., arm_detailed.
2012-09-20 17:25:52 -04:00
Andreas Hansson
a731f8f9dd Mem: Remove the file parameter from AbstractMemory
This patch removes the unused file parameter from the
AbstractMemory. The patch serves to make it easier to transition to a
separation of the actual contigious host memory backing store, and the
gem5 memory controllers.

Without the file parameter it becomes easier to hide the creation of
the mmap in the PhysicalMemory, as there are no longer any reasons to
expose the actual contigious ranges to the user.

To the best of my knowledge there is no use of the parameter, so the
change should not affect anyone.
2012-09-19 06:15:46 -04:00
Andreas Hansson
ffb6aec603 AddrRange: Transition from Range<T> to AddrRange
This patch takes the final plunge and transitions from the templated
Range class to the more specific AddrRange. In doing so it changes the
obvious Range<Addr> to AddrRange, and also bumps the range_map to be
AddrRangeMap.

In addition to the obvious changes, including the removal of redundant
includes, this patch also does some house keeping in preparing for the
introduction of address interleaving support in the ranges. The Range
class is also stripped of all the functionality that is never used.

--HG--
rename : src/base/range.hh => src/base/addr_range.hh
rename : src/base/range_map.hh => src/base/addr_range_map.hh
2012-09-19 06:15:44 -04:00
Nilay Vaish
33c904e0a5 ruby: eliminate typedef integer_t 2012-09-18 22:49:12 -05:00
Nilay Vaish
86b1c0fd54 ruby: avoid using g_system_ptr for event scheduling
This patch removes the use of g_system_ptr for event scheduling. Each consumer
object now needs to specify upfront an EventManager object it would use for
scheduling events. This makes the ruby memory system more amenable for a
multi-threaded simulation.
2012-09-18 22:46:34 -05:00
Andreas Hansson
7c55464aac Mem: Add a maximum bandwidth to SimpleMemory
This patch makes a minor addition to the SimpleMemory by enforcing a
maximum data rate. The bandwidth is configurable, and a reasonable
value (12.8GB/s) has been choosen as the default.

The changes do add some complexity to the SimpleMemory, but they
should definitely be justifiable as this enables a far more realistic
setup using even this simple memory controller.

The rate regulation is done for reads and writes combined to reflect
the bidirectional data busses used by most (if not all) relevant
memories. Moreover, the regulation is done per packet as opposed to
long term, as it is the short term data rate (data bus width times
frequency) that is the limiting factor.

A follow-up patch bumps the stats for the regressions.
2012-09-18 10:30:02 -04:00
Andreas Hansson
806a1144ce scons: Use c++0x with gcc >= 4.4 instead of 4.6
This patch shifts the version of gcc for which we enable c++0x from
4.6 to 4.4 The more long term plan is to see what the c++0x features
can bring and what level of support would be enabled simply by bumping
the required version of gcc from 4.3 to 4.4.

A few minor things had to be fixed in the code base, most notably the
choice of a hashmap implementation. In the Ruby Sequencer there were
also a few minor issues that gcc 4.4 was not too happy about.
2012-09-14 12:13:18 -04:00
Jason Power
aa8bcd15ec Ruby: Modify Scons so that we can put .sm files in extras
Also allows for header files which are required in slicc generated
code to be in a directory other than src/mem/ruby/slicc_interface.
2012-09-12 14:52:04 -05:00
Andreas Hansson
292d8252a4 clang: Fix issues identified by the clang static analyzer
This patch addresses a few minor issues reported by the clang static
analyzer.

The analysis was run with:

scan-build -disable-checker deadcode \
           -enable-checker experimental.core \
           -disable-checker experimental.core.CastToStruct \
           -enable-checker experimental.cpluscplus
2012-09-11 14:15:47 -04:00
Lena Olson
584eba3ab6 Cache: Split invalidateBlk up to seperate block vs. tags
This seperates the functionality to clear the state in a block into
blk.hh and the functionality to udpate the tag information into the
tags.  This gets rid of the case where calling invalidateBlk on an
already-invalid block does something different than calling it on a
valid block, which was confusing.
2012-09-11 14:14:49 -04:00
Nilay Vaish
637c6c7e32 Ruby: Use uint32_t instead of uint32 everywhere 2012-09-11 09:24:45 -05:00
Nilay Vaish
f00347a20f Ruby: Use uint8_t instead of uint8 everywhere 2012-09-11 09:23:56 -05:00
Nilay Vaish
c5bf1390aa Ruby System: Convert to Clocked Object
This patch moves Ruby System from being a SimObject to recently introduced
ClockedObject.
2012-09-10 12:21:01 -05:00
Nilay Vaish
4e6f048ef0 Ruby Slicc: remove the call to cin.get() function
If I understand correctly, this was put in place so that a debugger can be
attached when the protocol aborts. While this sounds useful, it is a problem
when the simulation is not being actively monitored. I think it is better to
remove this.
2012-09-10 12:20:34 -05:00
Marco Elver
9e0edbcea8 Mem: Allow serializing of more than INT_MAX bytes
Despite gzwrite taking an unsigned for length, it returns an int for
bytes written; gzwrite fails if (int)len < 0.  Because of this, call
gzwrite with len no larger than INT_MAX: write in blocks of INT_MAX if
data to be written is larger than INT_MAX.
2012-09-10 11:57:43 -04:00
Andreas Hansson
287ea1a081 Param: Transition to Cycles for relevant parameters
This patch is a first step to using Cycles as a parameter type. The
main affected modules are the CPUs and the Ruby caches. There are
definitely plenty more places that are affected, but this patch serves
as a starting point to making the transition.

An important part of this patch is to actually enable parameters to be
specified as Param.Cycles which involves some changes to params.py.
2012-09-07 12:34:38 -04:00
Joel Hestness
6924e10978 Ruby Memory Controller: Fix clocking 2012-09-05 20:51:41 -05:00
Jason Power
494f6a858e Ruby: Correct DataBlock =operator
The =operator for the DataBlock class was incorrectly interpreting the class
member m_alloc. This variable stands for whether the assigned memory for the
data block needs to be freed or not by the class itself. It seems that the
=operator interpreted the variable as whether the memory is assigned to the
data block. This wrong interpretation was causing values not to propagate
to RubySystem::m_mem_vec_ptr. This caused major issues with restoring from
checkpoints when using a protocol which verified that the cache data was
consistent with the backing store (i.e. MOESI-hammer).
2012-08-28 17:57:51 -05:00
Andreas Hansson
0cacf7e817 Clock: Add a Cycles wrapper class and use where applicable
This patch addresses the comments and feedback on the preceding patch
that reworks the clocks and now more clearly shows where cycles
(relative cycle counts) are used to express time.

Instead of bumping the existing patch I chose to make this a separate
patch, merely to try and focus the discussion around a smaller set of
changes. The two patches will be pushed together though.

This changes done as part of this patch are mostly following directly
from the introduction of the wrapper class, and change enough code to
make things compile and run again. There are definitely more places
where int/uint/Tick is still used to represent cycles, and it will
take some time to chase them all down. Similarly, a lot of parameters
should be changed from Param.Tick and Param.Unsigned to
Param.Cycles.

In addition, the use of curTick is questionable as there should not be
an absolute cycle. Potential solutions can be built on top of this
patch. There is a similar situation in the o3 CPU where
lastRunningCycle is currently counting in Cycles, and is still an
absolute time. More discussion to be had in other words.

An additional change that would be appropriate in the future is to
perform a similar wrapping of Tick and probably also introduce a
Ticks class along with suitable operators for all these classes.
2012-08-28 14:30:33 -04:00
Andreas Hansson
d14e5857c7 Port: Stricter port bind/unbind semantics
This patch tightens up the semantics around port binding and checks
that the ports that are being bound are currently not connected, and
similarly connected before unbind is called.

The patch consequently also changes the order of the unbind and bind
for the switching of CPUs to ensure that the rules are adhered
to. Previously the ports would be "over-written" without any check.

There are no changes in behaviour due to this patch, and the only
place where the unbind functionality is used is in the CPU.
2012-08-28 14:30:27 -04:00
Nilay Vaish
85c7352462 Ruby: remove README.debugging and Decommissioning_note
These files were relevant when Ruby was part of GEMS. They are not required
any longer.
2012-08-27 14:57:46 -05:00
Nilay Vaish
9190940511 Ruby: Remove RubyEventQueue
This patch removes RubyEventQueue. Consumer objects now rely on RubySystem
or themselves for scheduling events.
2012-08-27 01:00:55 -05:00
Nilay Vaish
7122b83d8f Ruby Memory Vector: Allow more than 4GB of memory
The memory size variable was a 32-bit int. This meant that the size of the
memory was limited to 4GB. This patch changes the type of the variable to
64-bit to support larger memory sizes. Thanks to Raghuraman Balasubramanian
for bringing this to notice.
2012-08-27 01:00:54 -05:00
Nilay Vaish
b422994fea MESI Protocol: Correct the virtual network in profile functions
The virtual network in a couple of places was incorrectly mentioned
as 3 in place of 1. This is being corrected.
2012-08-25 15:49:06 -05:00
Nilay Vaish
01f1430833 MESI Coherence Protocol: Add copyright notice 2012-08-25 13:16:45 -05:00
Andreas Hansson
c60db56741 Packet: Remove NACKs from packet and its use in endpoints
This patch removes the NACK frrom the packet as there is no longer any
module in the system that issues them (the bridge was the only one and
the previous patch removes that).

The handling of NACKs was mostly avoided throughout the code base, by
using e.g. panic or assert false, but in a few locations the NACKs
were actually dealt with (although NACKs never occured in any of the
regressions). Most notably, the DMA port will now never receive a NACK
and the backoff time is thus never changed. As a consequence, the
entire backoff mechanism (similar to a PCI bus) is now removed and the
DMA port entirely relies on the bus performing the arbitration and
issuing a retry when appropriate. This is more in line with e.g. PCIe.

Surprisingly, this patch has no impact on any of the regressions. As
mentioned in the patch that removes the NACK from the bridge, a
follow-up patch should change the request and response buffer size for
at least one regression to also verify that the system behaves as
expected when the bridge fills up.
2012-08-22 11:39:59 -04:00
Andreas Hansson
a6074016e2 Bridge: Remove NACKs in the bridge and unify with packet queue
This patch removes the NACKing in the bridge, as the split
request/response busses now ensure that protocol deadlocks do not
occur, i.e. the message-dependency chain is broken by always allowing
responses to make progress without being stalled by requests. The
NACKs had limited support in the system with most components ignoring
their use (with a suitable call to panic), and as the NACKs are no
longer needed to avoid protocol deadlocks, the cleanest way is to
simply remove them.

The bridge is the starting point as this is the only place where the
NACKs are created. A follow-up patch will remove the code that deals
with NACKs in the endpoints, e.g. the X86 table walker and DMA
port. Ultimately the type of packet can be complete removed (until
someone sees a need for modelling more complex protocols, which can
now be done in parts of the system since the port and interface is
split).

As a consequence of the NACK removal, the bridge now has to send a
retry to a master if the request or response queue was full on the
first attempt. This change also makes the bridge ports very similar to
QueuedPorts, and a later patch will change the bridge to use these. A
first step in this direction is taken by aligning the name of the
member functions, as done by this patch.

A bit of tidying up has also been done as part of the simplifications.

Surprisingly, this patch has no impact on any of the
regressions. Hence, there was never any NACKs issued. In a follow-up
patch I would suggest changing the size of the bridge buffers set in
FSConfig.py to also test the situation where the bridge fills up.
2012-08-22 11:39:58 -04:00
Andreas Hansson
e317d8b9ff Port: Extend the QueuedPort interface and use where appropriate
This patch extends the queued port interfaces with methods for
scheduling the transmission of a timing request/response. The methods
are named similar to the corresponding sendTiming(Snoop)Req/Resp,
replacing the "send" with "sched". As the queues are currently
unbounded, the methods always succeed and hence do not return a value.

This functionality was previously provided in the subclasses by
calling PacketQueue::schedSendTiming with the appropriate
parameters. With this change, there is no need to introduce these
extra methods in the subclasses, and the use of the queued interface
is more uniform and explicit.
2012-08-22 11:39:56 -04:00
Andreas Hansson
5803309574 PacketQueue: Allow queuing in the same tick as desired send tick
This patch allows packets to be enqueued in the same tick as they are
intended to be sent. This does not imply they actually are sent that
tick, although that is possible.

This change is useful for module that use the queued ports primarly to
avoid handling the flow control involved in sending and retrying
packets.
2012-08-21 05:49:24 -04:00
Andreas Hansson
452217817f Clock: Move the clock and related functions to ClockedObject
This patch moves the clock of the CPU, bus, and numerous devices to
the new class ClockedObject, that sits in between the SimObject and
MemObject in the class hierarchy. Although there are currently a fair
amount of MemObjects that do not make use of the clock, they
potentially should do so, e.g. the caches should at some point have
the same clock as the CPU, potentially with a 1:n ratio. This patch
does not introduce any new clock objects or object hierarchies
(clusters, clock domains etc), but is still a step in the direction of
having a more structured approach clock domains.

The most contentious part of this patch is the serialisation of clocks
that some of the modules (but not all) did previously. This
serialisation should not be needed as the clock is set through the
parameters even when restoring from the checkpoint. In other words,
the state is "stored" in the Python code that creates the modules.

The nextCycle methods are also simplified and the clock phase
parameter of the CPU is removed (this could be part of a clock object
once they are introduced).
2012-08-21 05:49:01 -04:00
Nilay Vaish
0160d51483 Ruby Banked Array: add copyrights 2012-08-19 13:05:53 -05:00
Jason Power
44b4c96253 Ruby: Add RubySystem parameter to MemoryControl
This guarantees that RubySystem object is created before the MemoryController
object is created.
2012-08-16 23:39:36 -05:00
Anthony Gutierrez
0b3897fc90 O3,ARM: fix some problems with drain/switchout functionality and add Drain DPRINTFs
This patch fixes some problems with the drain/switchout functionality
for the O3 cpu and for the ARM ISA and adds some useful debug print
statements.

This is an incremental fix as there are still a few bugs/mem leaks with the
switchout code. Particularly when switching from an O3CPU to a
TimingSimpleCPU. However, when switching from O3 to O3 cores with the ARM ISA
I haven't encountered any more assertion failures; now the kernel will
typically panic inside of simulation.
2012-08-15 10:38:08 -04:00
Jason Power
11411cc9c7 Ruby: Clean up topology changes
This patch moves instantiateTopology into Ruby.py and removes the
mem/ruby/network/topologies directory. It also adds some extra inheritance to
the topologies to clean up some issues in the existing topologies.
2012-08-10 13:50:42 -05:00
Steve Reinhardt
f4b424cd53 SETranslatingPortProxy: fix bug in tryReadString()
Off-by-one loop termination meant that we were stuffing
the terminating '\0' into the std::string value, which
makes for difficult-to-debug string comparison failures.
2012-08-06 16:57:11 -07:00
Jason Power
6721b3e325 Ruby NetDest: add assert for bad element in netdest 2012-08-01 17:07:34 -05:00
Anthony Gutierrez
7bf14aedbf cache: don't allow dirty data in the i-cache
removes the optimization that forwards an exclusive copy to a requester on a
read, only for the i-cache. this optimization isn't necessary because we
typically won't be writing to the i-cache.
2012-07-27 16:08:04 -04:00
Andreas Hansson
66f5124e2b Bridge: Use EventWrapper instead of Event subclass for sendEvent
This class simply cleans up the code by making use of the EventWrapper
convenience class to schedule the sendEvent in the bridge ports.
2012-07-23 09:32:19 -04:00
Andreas Hansson
f00cba34eb Mem: Make SimpleMemory single ported
This patch changes the simple memory to have a single slave port
rather than a vector port. The simple memory makes no attempts at
modelling the contention between multiple ports, and any such
multiplexing and demultiplexing could be done in a bus (or crossbar)
outside the memory controller. This scenario also matches with the
ongoing work on a SimpleDRAM model, which will be a single-ported
single-channel controller that can be used in conjunction with a bus
(or crossbar) to create a multi-port multi-channel controller.

There are only very few regressions that make use of the vector port,
and these are all for functional accesses only. To facilitate these
cases, memtest and memtest-ruby have been updated to also have a
"functional" bus to perform the (de)multiplexing of the functional
memory accesses.
2012-07-12 12:56:13 -04:00
Nilay Vaish
b913af440b Ruby: remove config information from ruby.stats
This patch removes printConfig() functions from all structures in Ruby.
Most of the information is already part of config.ini, and where ever it
is not, it would become in due course.
2012-07-12 08:39:19 -05:00