diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/cpu/BaseCPU.py | 4 | ||||
| -rw-r--r-- | src/mem/Bus.py | 48 | ||||
| -rw-r--r-- | src/mem/SConscript | 9 | ||||
| -rw-r--r-- | src/mem/bus.cc | 492 | ||||
| -rw-r--r-- | src/mem/bus.hh | 247 | ||||
| -rw-r--r-- | src/mem/coherent_bus.cc | 493 | ||||
| -rw-r--r-- | src/mem/coherent_bus.hh | 290 | ||||
| -rw-r--r-- | src/mem/noncoherent_bus.cc | 209 | ||||
| -rw-r--r-- | src/mem/noncoherent_bus.hh | 201 |
9 files changed, 1295 insertions, 698 deletions
diff --git a/src/cpu/BaseCPU.py b/src/cpu/BaseCPU.py index 60d06b209..9ed2cb789 100644 --- a/src/cpu/BaseCPU.py +++ b/src/cpu/BaseCPU.py @@ -47,7 +47,7 @@ from m5.defines import buildEnv from m5.params import * from m5.proxy import * -from Bus import Bus +from Bus import CoherentBus from InstTracer import InstTracer from ExeTracer import ExeTracer from MemObject import MemObject @@ -223,7 +223,7 @@ class BaseCPU(MemObject): def addTwoLevelCacheHierarchy(self, ic, dc, l2c, iwc = None, dwc = None): self.addPrivateSplitL1Caches(ic, dc, iwc, dwc) - self.toL2Bus = Bus() + self.toL2Bus = CoherentBus() self.connectCachedPorts(self.toL2Bus) self.l2cache = l2c self.toL2Bus.master = self.l2cache.cpu_side diff --git a/src/mem/Bus.py b/src/mem/Bus.py index 91043da80..05033d382 100644 --- a/src/mem/Bus.py +++ b/src/mem/Bus.py @@ -1,3 +1,15 @@ +# Copyright (c) 2012 ARM Limited +# All rights reserved. +# +# The license below extends only to copyright in the software and shall +# not be construed as granting a license to any other intellectual +# property including but not limited to intellectual property relating +# to a hardware implementation of the functionality of the software +# licensed hereunder. You may use the software subject to the license +# terms below provided that you ensure that this notice is replicated +# unmodified and in its entirety in all distributions of the software, +# modified or unmodified, in source code or in binary form. +# # Copyright (c) 2005-2008 The Regents of The University of Michigan # All rights reserved. # @@ -25,22 +37,36 @@ # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. # # Authors: Nathan Binkert +# Andreas Hansson -from m5.defines import buildEnv -from m5.params import * -from m5.proxy import * from MemObject import MemObject +from m5.params import * -class Bus(MemObject): - type = 'Bus' +class BaseBus(MemObject): + type = 'BaseBus' + abstract = True slave = VectorSlavePort("vector port for connecting masters") master = VectorMasterPort("vector port for connecting slaves") - bus_id = Param.Int(0, "blah") clock = Param.Clock("1GHz", "bus clock speed") header_cycles = Param.Int(1, "cycles of overhead per transaction") width = Param.Int(64, "bus width (bytes)") - block_size = Param.Int(64, "The default block size if one isn't set by a device attached to the bus.") - default = MasterPort("Default port for requests that aren't handled " \ - "by a device.") - use_default_range = \ - Param.Bool(False, "Query default port device for legal range.") + block_size = Param.Int(64, "The default block size if not set by " \ + "any connected module") + + # The default port can be left unconnected, or be used to connect + # a default slave port + default = MasterPort("Port for connecting an optional default slave") + + # The default port can be used unconditionally, or based on + # address range, in which case it may overlap with other + # ports. The default range is always checked first, thus creating + # a two-level hierarchical lookup. This is useful e.g. for the PCI + # bus configuration. + use_default_range = Param.Bool(False, "Perform address mapping for " \ + "the default port") + +class NoncoherentBus(BaseBus): + type = 'NoncoherentBus' + +class CoherentBus(BaseBus): + type = 'CoherentBus' diff --git a/src/mem/SConscript b/src/mem/SConscript index 3ffb3503a..1961204f7 100644 --- a/src/mem/SConscript +++ b/src/mem/SConscript @@ -37,9 +37,11 @@ SimObject('MemObject.py') Source('bridge.cc') Source('bus.cc') +Source('coherent_bus.cc') Source('comm_monitor.cc') Source('mem_object.cc') Source('mport.cc') +Source('noncoherent_bus.cc') Source('packet.cc') Source('port.cc') Source('packet_queue.cc') @@ -56,8 +58,13 @@ if env['TARGET_ISA'] != 'no': Source('page_table.cc') Source('physical.cc') -DebugFlag('Bus') +DebugFlag('BaseBus') DebugFlag('BusAddrRanges') +DebugFlag('CoherentBus') +DebugFlag('NoncoherentBus') +CompoundFlag('Bus', ['BaseBus', 'BusAddrRanges', 'CoherentBus', + 'NoncoherentBus']) + DebugFlag('BusBridge') DebugFlag('CommMonitor') DebugFlag('LLSC') diff --git a/src/mem/bus.cc b/src/mem/bus.cc index a22b0e7fd..8040118d2 100644 --- a/src/mem/bus.cc +++ b/src/mem/bus.cc @@ -53,7 +53,7 @@ #include "debug/BusAddrRanges.hh" #include "mem/bus.hh" -Bus::Bus(const BusParams *p) +BaseBus::BaseBus(const BaseBusParams *p) : MemObject(p), clock(p->clock), headerCycles(p->header_cycles), width(p->width), tickNextIdle(0), drainEvent(NULL), busIdleEvent(this), inRetry(false), @@ -69,37 +69,23 @@ Bus::Bus(const BusParams *p) fatal("Bus clock period must be positive\n"); if (headerCycles <= 0) fatal("Number of header cycles must be positive\n"); +} - // create the ports based on the size of the master and slave - // vector ports, and the presence of the default port, the ports - // are enumerated starting from zero - for (int i = 0; i < p->port_master_connection_count; ++i) { - std::string portName = csprintf("%s-p%d", name(), i); - MasterPort* bp = new BusMasterPort(portName, this, i); - masterPorts.push_back(bp); - } - - // see if we have a default slave device connected and if so add - // our corresponding master port - if (p->port_default_connection_count) { - defaultPortID = masterPorts.size(); - std::string portName = csprintf("%s-default", name()); - MasterPort* bp = new BusMasterPort(portName, this, defaultPortID); - masterPorts.push_back(bp); +BaseBus::~BaseBus() +{ + for (MasterPortIter m = masterPorts.begin(); m != masterPorts.end(); + ++m) { + delete *m; } - // create the slave ports, once again starting at zero - for (int i = 0; i < p->port_slave_connection_count; ++i) { - std::string portName = csprintf("%s-p%d", name(), i); - SlavePort* bp = new BusSlavePort(portName, this, i); - slavePorts.push_back(bp); + for (SlavePortIter s = slavePorts.begin(); s != slavePorts.end(); + ++s) { + delete *s; } - - clearPortCache(); } MasterPort & -Bus::getMasterPort(const std::string &if_name, int idx) +BaseBus::getMasterPort(const std::string &if_name, int idx) { if (if_name == "master" && idx < masterPorts.size()) { // the master port index translates directly to the vector position @@ -112,7 +98,7 @@ Bus::getMasterPort(const std::string &if_name, int idx) } SlavePort & -Bus::getSlavePort(const std::string &if_name, int idx) +BaseBus::getSlavePort(const std::string &if_name, int idx) { if (if_name == "slave" && idx < slavePorts.size()) { // the slave port index translates directly to the vector position @@ -122,23 +108,8 @@ Bus::getSlavePort(const std::string &if_name, int idx) } } -void -Bus::init() -{ - // iterate over our slave ports and determine which of our - // neighbouring master ports are snooping and add them as snoopers - for (SlavePortConstIter p = slavePorts.begin(); p != slavePorts.end(); - ++p) { - if ((*p)->getMasterPort().isSnooping()) { - DPRINTF(BusAddrRanges, "Adding snooping neighbour %s\n", - (*p)->getMasterPort().name()); - snoopPorts.push_back(*p); - } - } -} - Tick -Bus::calcPacketTiming(PacketPtr pkt) +BaseBus::calcPacketTiming(PacketPtr pkt) { // determine the current time rounded to the closest following // clock edge @@ -169,7 +140,7 @@ Bus::calcPacketTiming(PacketPtr pkt) return headerTime; } -void Bus::occupyBus(Tick until) +void BaseBus::occupyBus(Tick until) { if (until == 0) { // shortcut for express snoop packets @@ -179,12 +150,12 @@ void Bus::occupyBus(Tick until) tickNextIdle = until; reschedule(busIdleEvent, tickNextIdle, true); - DPRINTF(Bus, "The bus is now occupied from tick %d to %d\n", + DPRINTF(BaseBus, "The bus is now occupied from tick %d to %d\n", curTick(), tickNextIdle); } bool -Bus::isOccupied(Port* port) +BaseBus::isOccupied(Port* port) { // first we see if the next idle tick is in the future, next the // bus is considered occupied if there are ports on the retry list @@ -197,220 +168,15 @@ Bus::isOccupied(Port* port) return false; } -bool -Bus::recvTimingReq(PacketPtr pkt, PortID slave_port_id) -{ - // determine the source port based on the id - SlavePort *src_port = slavePorts[slave_port_id]; - - // test if the bus should be considered occupied for the current - // port, and exclude express snoops from the check - if (!pkt->isExpressSnoop() && isOccupied(src_port)) { - DPRINTF(Bus, "recvTimingReq: src %s %s 0x%x BUSY\n", - src_port->name(), pkt->cmdString(), pkt->getAddr()); - return false; - } - - DPRINTF(Bus, "recvTimingReq: src %s %s 0x%x\n", - src_port->name(), pkt->cmdString(), pkt->getAddr()); - - // set the source port for routing of the response - pkt->setSrc(slave_port_id); - - Tick headerFinishTime = pkt->isExpressSnoop() ? 0 : calcPacketTiming(pkt); - Tick packetFinishTime = pkt->isExpressSnoop() ? 0 : pkt->finishTime; - - // uncacheable requests need never be snooped - if (!pkt->req->isUncacheable()) { - // the packet is a memory-mapped request and should be - // broadcasted to our snoopers but the source - forwardTiming(pkt, slave_port_id); - } - - // remember if we add an outstanding req so we can undo it if - // necessary, if the packet needs a response, we should add it - // as outstanding and express snoops never fail so there is - // not need to worry about them - bool add_outstanding = !pkt->isExpressSnoop() && pkt->needsResponse(); - - // keep track that we have an outstanding request packet - // matching this request, this is used by the coherency - // mechanism in determining what to do with snoop responses - // (in recvTimingSnoop) - if (add_outstanding) { - // we should never have an exsiting request outstanding - assert(outstandingReq.find(pkt->req) == outstandingReq.end()); - outstandingReq.insert(pkt->req); - } - - // since it is a normal request, determine the destination - // based on the address and attempt to send the packet - bool success = masterPorts[findPort(pkt->getAddr())]->sendTimingReq(pkt); - - if (!success) { - // inhibited packets should never be forced to retry - assert(!pkt->memInhibitAsserted()); - - // if it was added as outstanding and the send failed, then - // erase it again - if (add_outstanding) - outstandingReq.erase(pkt->req); - - DPRINTF(Bus, "recvTimingReq: src %s %s 0x%x RETRY\n", - src_port->name(), pkt->cmdString(), pkt->getAddr()); - - addToRetryList(src_port); - occupyBus(headerFinishTime); - - return false; - } - - succeededTiming(packetFinishTime); - - return true; -} - -bool -Bus::recvTimingResp(PacketPtr pkt, PortID master_port_id) -{ - // determine the source port based on the id - MasterPort *src_port = masterPorts[master_port_id]; - - // test if the bus should be considered occupied for the current - // port - if (isOccupied(src_port)) { - DPRINTF(Bus, "recvTimingResp: src %s %s 0x%x BUSY\n", - src_port->name(), pkt->cmdString(), pkt->getAddr()); - return false; - } - - DPRINTF(Bus, "recvTimingResp: src %s %s 0x%x\n", - src_port->name(), pkt->cmdString(), pkt->getAddr()); - - calcPacketTiming(pkt); - Tick packetFinishTime = pkt->finishTime; - - // the packet is a normal response to a request that we should - // have seen passing through the bus - assert(outstandingReq.find(pkt->req) != outstandingReq.end()); - - // remove it as outstanding - outstandingReq.erase(pkt->req); - - // send the packet to the destination through one of our slave - // ports, as determined by the destination field - bool success M5_VAR_USED = slavePorts[pkt->getDest()]->sendTimingResp(pkt); - - // currently it is illegal to block responses... can lead to - // deadlock - assert(success); - - succeededTiming(packetFinishTime); - - return true; -} - void -Bus::recvTimingSnoopReq(PacketPtr pkt, PortID master_port_id) -{ - DPRINTF(Bus, "recvTimingSnoopReq: src %s %s 0x%x\n", - masterPorts[master_port_id]->name(), pkt->cmdString(), - pkt->getAddr()); - - // we should only see express snoops from caches - assert(pkt->isExpressSnoop()); - - // set the source port for routing of the response - pkt->setSrc(master_port_id); - - // forward to all snoopers - forwardTiming(pkt, InvalidPortID); - - // a snoop request came from a connected slave device (one of - // our master ports), and if it is not coming from the slave - // device responsible for the address range something is - // wrong, hence there is nothing further to do as the packet - // would be going back to where it came from - assert(master_port_id == findPort(pkt->getAddr())); - - // this is an express snoop and is never forced to retry - assert(!inRetry); -} - -bool -Bus::recvTimingSnoopResp(PacketPtr pkt, PortID slave_port_id) -{ - // determine the source port based on the id - SlavePort* src_port = slavePorts[slave_port_id]; - - // test if the bus should be considered occupied for the current - // port - if (isOccupied(src_port)) { - DPRINTF(Bus, "recvTimingSnoopResp: src %s %s 0x%x BUSY\n", - src_port->name(), pkt->cmdString(), pkt->getAddr()); - return false; - } - - DPRINTF(Bus, "recvTimingSnoop: src %s %s 0x%x\n", - src_port->name(), pkt->cmdString(), pkt->getAddr()); - - // get the destination from the packet - PortID dest = pkt->getDest(); - - // responses are never express snoops - assert(!pkt->isExpressSnoop()); - - calcPacketTiming(pkt); - Tick packetFinishTime = pkt->finishTime; - - // determine if the response is from a snoop request we - // created as the result of a normal request (in which case it - // should be in the outstandingReq), or if we merely forwarded - // someone else's snoop request - if (outstandingReq.find(pkt->req) == outstandingReq.end()) { - // this is a snoop response to a snoop request we - // forwarded, e.g. coming from the L1 and going to the L2 - // this should be forwarded as a snoop response - bool success M5_VAR_USED = masterPorts[dest]->sendTimingSnoopResp(pkt); - assert(success); - } else { - // we got a snoop response on one of our slave ports, - // i.e. from a coherent master connected to the bus, and - // since we created the snoop request as part of - // recvTiming, this should now be a normal response again - outstandingReq.erase(pkt->req); - - // this is a snoop response from a coherent master, with a - // destination field set on its way through the bus as - // request, hence it should never go back to where the - // snoop response came from, but instead to where the - // original request came from - assert(slave_port_id != dest); - - // as a normal response, it should go back to a master - // through one of our slave ports - bool success M5_VAR_USED = slavePorts[dest]->sendTimingResp(pkt); - - // currently it is illegal to block responses... can lead - // to deadlock - assert(success); - } - - succeededTiming(packetFinishTime); - - return true; -} - - -void -Bus::succeededTiming(Tick busy_time) +BaseBus::succeededTiming(Tick busy_time) { // occupy the bus accordingly occupyBus(busy_time); // if a retrying port succeeded, also take it off the retry list if (inRetry) { - DPRINTF(Bus, "Remove retry from list %s\n", + DPRINTF(BaseBus, "Remove retry from list %s\n", retryList.front()->name()); retryList.pop_front(); inRetry = false; @@ -418,24 +184,7 @@ Bus::succeededTiming(Tick busy_time) } void -Bus::forwardTiming(PacketPtr pkt, PortID exclude_slave_port_id) -{ - for (SlavePortIter s = snoopPorts.begin(); s != snoopPorts.end(); ++s) { - SlavePort *p = *s; - // we could have gotten this request from a snooping master - // (corresponding to our own slave port that is also in - // snoopPorts) and should not send it back to where it came - // from - if (exclude_slave_port_id == InvalidPortID || - p->getId() != exclude_slave_port_id) { - // cache is not allowed to refuse snoop - p->sendTimingSnoopReq(pkt); - } - } -} - -void -Bus::releaseBus() +BaseBus::releaseBus() { // releasing the bus means we should now be idle assert(curTick() >= tickNextIdle); @@ -458,7 +207,7 @@ Bus::releaseBus() } void -Bus::retryWaiting() +BaseBus::retryWaiting() { // this should never be called with an empty retry list assert(!retryList.empty()); @@ -489,7 +238,7 @@ Bus::retryWaiting() } void -Bus::recvRetry() +BaseBus::recvRetry() { // we got a retry from a peer that we tried to send something to // and failed, but we sent it on the account of someone else, and @@ -509,7 +258,7 @@ Bus::recvRetry() } PortID -Bus::findPort(Addr addr) +BaseBus::findPort(Addr addr) { /* An interval tree would be a better way to do this. --ali. */ PortID dest_id = checkPortCache(addr); @@ -529,12 +278,13 @@ Bus::findPort(Addr addr) AddrRangeIter a_end = defaultRange.end(); for (AddrRangeIter i = defaultRange.begin(); i != a_end; i++) { if (*i == addr) { - DPRINTF(Bus, " found addr %#llx on default\n", addr); + DPRINTF(BusAddrRanges, " found addr %#llx on default\n", + addr); return defaultPortID; } } } else if (defaultPortID != InvalidPortID) { - DPRINTF(Bus, "Unable to find destination for addr %#llx, " + DPRINTF(BusAddrRanges, "Unable to find destination for addr %#llx, " "will use default port\n", addr); return defaultPortID; } @@ -545,170 +295,9 @@ Bus::findPort(Addr addr) name()); } -Tick -Bus::recvAtomic(PacketPtr pkt, PortID slave_port_id) -{ - DPRINTF(Bus, "recvAtomic: packet src %s addr 0x%x cmd %s\n", - slavePorts[slave_port_id]->name(), pkt->getAddr(), - pkt->cmdString()); - - MemCmd snoop_response_cmd = MemCmd::InvalidCmd; - Tick snoop_response_latency = 0; - - // uncacheable requests need never be snooped - if (!pkt->req->isUncacheable()) { - // forward to all snoopers but the source - std::pair<MemCmd, Tick> snoop_result = - forwardAtomic(pkt, slave_port_id); - snoop_response_cmd = snoop_result.first; - snoop_response_latency = snoop_result.second; - } - - // even if we had a snoop response, we must continue and also - // perform the actual request at the destination - PortID dest_id = findPort(pkt->getAddr()); - - // forward the request to the appropriate destination - Tick response_latency = masterPorts[dest_id]->sendAtomic(pkt); - - // if we got a response from a snooper, restore it here - if (snoop_response_cmd != MemCmd::InvalidCmd) { - // no one else should have responded - assert(!pkt->isResponse()); - pkt->cmd = snoop_response_cmd; - response_latency = snoop_response_latency; - } - - pkt->finishTime = curTick() + response_latency; - return response_latency; -} - -Tick -Bus::recvAtomicSnoop(PacketPtr pkt, PortID master_port_id) -{ - DPRINTF(Bus, "recvAtomicSnoop: packet src %s addr 0x%x cmd %s\n", - masterPorts[master_port_id]->name(), pkt->getAddr(), - pkt->cmdString()); - - // forward to all snoopers - std::pair<MemCmd, Tick> snoop_result = - forwardAtomic(pkt, InvalidPortID); - MemCmd snoop_response_cmd = snoop_result.first; - Tick snoop_response_latency = snoop_result.second; - - if (snoop_response_cmd != MemCmd::InvalidCmd) - pkt->cmd = snoop_response_cmd; - - pkt->finishTime = curTick() + snoop_response_latency; - return snoop_response_latency; -} - -std::pair<MemCmd, Tick> -Bus::forwardAtomic(PacketPtr pkt, PortID exclude_slave_port_id) -{ - // the packet may be changed on snoops, record the original - // command to enable us to restore it between snoops so that - // additional snoops can take place properly - MemCmd orig_cmd = pkt->cmd; - MemCmd snoop_response_cmd = MemCmd::InvalidCmd; - Tick snoop_response_latency = 0; - - for (SlavePortIter s = snoopPorts.begin(); s != snoopPorts.end(); ++s) { - SlavePort *p = *s; - // we could have gotten this request from a snooping master - // (corresponding to our own slave port that is also in - // snoopPorts) and should not send it back to where it came - // from - if (exclude_slave_port_id == InvalidPortID || - p->getId() != exclude_slave_port_id) { - Tick latency = p->sendAtomicSnoop(pkt); - // in contrast to a functional access, we have to keep on - // going as all snoopers must be updated even if we get a - // response - if (pkt->isResponse()) { - // response from snoop agent - assert(pkt->cmd != orig_cmd); - assert(pkt->memInhibitAsserted()); - // should only happen once - assert(snoop_response_cmd == MemCmd::InvalidCmd); - // save response state - snoop_response_cmd = pkt->cmd; - snoop_response_latency = latency; - // restore original packet state for remaining snoopers - pkt->cmd = orig_cmd; - } - } - } - - // the packet is restored as part of the loop and any potential - // snoop response is part of the returned pair - return std::make_pair(snoop_response_cmd, snoop_response_latency); -} - -void -Bus::recvFunctional(PacketPtr pkt, PortID slave_port_id) -{ - if (!pkt->isPrint()) { - // don't do DPRINTFs on PrintReq as it clutters up the output - DPRINTF(Bus, - "recvFunctional: packet src %s addr 0x%x cmd %s\n", - slavePorts[slave_port_id]->name(), pkt->getAddr(), - pkt->cmdString()); - } - - // uncacheable requests need never be snooped - if (!pkt->req->isUncacheable()) { - // forward to all snoopers but the source - forwardFunctional(pkt, slave_port_id); - } - - // there is no need to continue if the snooping has found what we - // were looking for and the packet is already a response - if (!pkt->isResponse()) { - PortID dest_id = findPort(pkt->getAddr()); - - masterPorts[dest_id]->sendFunctional(pkt); - } -} - -void -Bus::recvFunctionalSnoop(PacketPtr pkt, PortID master_port_id) -{ - if (!pkt->isPrint()) { - // don't do DPRINTFs on PrintReq as it clutters up the output - DPRINTF(Bus, - "recvFunctionalSnoop: packet src %s addr 0x%x cmd %s\n", - masterPorts[master_port_id]->name(), pkt->getAddr(), - pkt->cmdString()); - } - - // forward to all snoopers - forwardFunctional(pkt, InvalidPortID); -} - -void -Bus::forwardFunctional(PacketPtr pkt, PortID exclude_slave_port_id) -{ - for (SlavePortIter s = snoopPorts.begin(); s != snoopPorts.end(); ++s) { - SlavePort *p = *s; - // we could have gotten this request from a snooping master - // (corresponding to our own slave port that is also in - // snoopPorts) and should not send it back to where it came - // from - if (exclude_slave_port_id == InvalidPortID || - p->getId() != exclude_slave_port_id) - p->sendFunctionalSnoop(pkt); - - // if we get a response we are done - if (pkt->isResponse()) { - break; - } - } -} - /** Function called by the port when the bus is receiving a range change.*/ void -Bus::recvRangeChange(PortID master_port_id) +BaseBus::recvRangeChange(PortID master_port_id) { AddrRangeList ranges; AddrRangeIter iter; @@ -773,7 +362,7 @@ Bus::recvRangeChange(PortID master_port_id) } AddrRangeList -Bus::getAddrRanges() +BaseBus::getAddrRanges() { AddrRangeList ranges; @@ -813,29 +402,22 @@ Bus::getAddrRanges() return ranges; } -bool -Bus::isSnooping() const -{ - // in essence, answer the question if there are snooping ports - return !snoopPorts.empty(); -} - unsigned -Bus::findBlockSize() +BaseBus::findBlockSize() { if (cachedBlockSizeValid) return cachedBlockSize; unsigned max_bs = 0; - PortIter p_end = portMap.end(); - for (PortIter p_iter = portMap.begin(); p_iter != p_end; p_iter++) { - unsigned tmp_bs = masterPorts[p_iter->second]->peerBlockSize(); + for (MasterPortConstIter m = masterPorts.begin(); m != masterPorts.end(); + ++m) { + unsigned tmp_bs = (*m)->peerBlockSize(); if (tmp_bs > max_bs) max_bs = tmp_bs; } - for (SlavePortConstIter s = snoopPorts.begin(); s != snoopPorts.end(); + for (SlavePortConstIter s = slavePorts.begin(); s != slavePorts.end(); ++s) { unsigned tmp_bs = (*s)->peerBlockSize(); if (tmp_bs > max_bs) @@ -853,7 +435,7 @@ Bus::findBlockSize() unsigned int -Bus::drain(Event * de) +BaseBus::drain(Event * de) { //We should check that we're not "doing" anything, and that noone is //waiting. We might be idle but have someone waiting if the device we @@ -867,14 +449,8 @@ Bus::drain(Event * de) } void -Bus::startup() +BaseBus::startup() { if (tickNextIdle < curTick()) tickNextIdle = (curTick() / clock) * clock + clock; } - -Bus * -BusParams::create() -{ - return new Bus(this); -} diff --git a/src/mem/bus.hh b/src/mem/bus.hh index c35b46cc2..4f0e44b1c 100644 --- a/src/mem/bus.hh +++ b/src/mem/bus.hh @@ -45,7 +45,7 @@ /** * @file - * Declaration of a bus object. + * Declaration of an abstract bus base class. */ #ifndef __MEM_BUS_HH__ @@ -53,155 +53,26 @@ #include <list> #include <set> -#include <string> #include "base/range.hh" #include "base/range_map.hh" #include "base/types.hh" #include "mem/mem_object.hh" -#include "mem/packet.hh" -#include "mem/port.hh" -#include "params/Bus.hh" -#include "sim/eventq.hh" +#include "params/BaseBus.hh" -class Bus : public MemObject +/** + * The base bus contains the common elements of the non-coherent and + * coherent bus. It is an abstract class that does not have any of the + * functionality relating to the actual reception and transmission of + * packets, as this is left for the subclasses. + * + * The BaseBus is responsible for the basic flow control (busy or + * not), the administration of retries, and the address decoding. + */ +class BaseBus : public MemObject { - /** - * Declaration of the bus slave port type, one will be - * instantiated for each of the master interfaces connecting to - * the bus. - */ - class BusSlavePort : public SlavePort - { - private: - /** A pointer to the bus to which this port belongs. */ - Bus *bus; - - public: - - /** Constructor for the BusSlavePort.*/ - BusSlavePort(const std::string &_name, Bus *_bus, PortID _id) - : SlavePort(_name, _bus, _id), bus(_bus) - { } - - protected: - - /** - * When receiving a timing request, pass it to the bus. - */ - virtual bool recvTimingReq(PacketPtr pkt) - { return bus->recvTimingReq(pkt, id); } - - /** - * When receiving a timing snoop response, pass it to the bus. - */ - virtual bool recvTimingSnoopResp(PacketPtr pkt) - { return bus->recvTimingSnoopResp(pkt, id); } - - /** - * When receiving an atomic request, pass it to the bus. - */ - virtual Tick recvAtomic(PacketPtr pkt) - { return bus->recvAtomic(pkt, id); } - - /** - * When receiving a functional request, pass it to the bus. - */ - virtual void recvFunctional(PacketPtr pkt) - { bus->recvFunctional(pkt, id); } - - /** - * When receiving a retry, pass it to the bus. - */ - virtual void recvRetry() - { panic("Bus slave ports always succeed and should never retry.\n"); } - - // This should return all the 'owned' addresses that are - // downstream from this bus, yes? That is, the union of all - // the 'owned' address ranges of all the other interfaces on - // this bus... - virtual AddrRangeList getAddrRanges() - { return bus->getAddrRanges(); } - - // Ask the bus to ask everyone on the bus what their block size is and - // take the max of it. This might need to be changed a bit if we ever - // support multiple block sizes. - virtual unsigned deviceBlockSize() const - { return bus->findBlockSize(); } - - }; - - /** - * Declaration of the bus master port type, one will be - * instantiated for each of the slave interfaces connecting to the - * bus. - */ - class BusMasterPort : public MasterPort - { - private: - /** A pointer to the bus to which this port belongs. */ - Bus *bus; - - public: - - /** Constructor for the BusMasterPort.*/ - BusMasterPort(const std::string &_name, Bus *_bus, PortID _id) - : MasterPort(_name, _bus, _id), bus(_bus) - { } - - /** - * Determine if this port should be considered a snooper. This - * is determined by the bus. - * - * @return a boolean that is true if this port is snooping - */ - virtual bool isSnooping() const - { return bus->isSnooping(); } - - protected: - - /** - * When receiving a timing response, pass it to the bus. - */ - virtual bool recvTimingResp(PacketPtr pkt) - { return bus->recvTimingResp(pkt, id); } - - /** - * When receiving a timing snoop request, pass it to the bus. - */ - virtual void recvTimingSnoopReq(PacketPtr pkt) - { return bus->recvTimingSnoopReq(pkt, id); } - - /** - * When receiving an atomic snoop request, pass it to the bus. - */ - virtual Tick recvAtomicSnoop(PacketPtr pkt) - { return bus->recvAtomicSnoop(pkt, id); } - - /** - * When receiving a functional snoop request, pass it to the bus. - */ - virtual void recvFunctionalSnoop(PacketPtr pkt) - { bus->recvFunctionalSnoop(pkt, id); } - - /** When reciving a range change from the peer port (at id), - pass it to the bus. */ - virtual void recvRangeChange() - { bus->recvRangeChange(id); } - - /** When reciving a retry from the peer port (at id), - pass it to the bus. */ - virtual void recvRetry() - { bus->recvRetry(); } - - // Ask the bus to ask everyone on the bus what their block size is and - // take the max of it. This might need to be changed a bit if we ever - // support multiple block sizes. - virtual unsigned deviceBlockSize() const - { return bus->findBlockSize(); } - - }; + protected: /** the clock speed for the bus */ int clock; @@ -219,41 +90,6 @@ class Bus : public MemObject AddrRangeList defaultRange; - std::vector<SlavePort*> snoopPorts; - - /** - * Store the outstanding requests so we can determine which ones - * we generated and which ones were merely forwarded. This is used - * in the coherent bus when coherency responses come back. - */ - std::set<RequestPtr> outstandingReq; - - /** Function called by the port when the bus is recieving a Timing - request packet.*/ - bool recvTimingReq(PacketPtr pkt, PortID slave_port_id); - - /** Function called by the port when the bus is recieving a Timing - response packet.*/ - bool recvTimingResp(PacketPtr pkt, PortID master_port_id); - - /** Function called by the port when the bus is recieving a timing - snoop request.*/ - void recvTimingSnoopReq(PacketPtr pkt, PortID master_port_id); - - /** Function called by the port when the bus is recieving a timing - snoop response.*/ - bool recvTimingSnoopResp(PacketPtr pkt, PortID slave_port_id); - - /** - * Forward a timing packet to our snoopers, potentially excluding - * one of the connected coherent masters to avoid sending a packet - * back to where it came from. - * - * @param pkt Packet to forward - * @param exclude_slave_port_id Id of slave port to exclude - */ - void forwardTiming(PacketPtr pkt, PortID exclude_slave_port_id); - /** * Determine if the bus is to be considered occupied when being * presented with a packet from a specific port. If so, the port @@ -274,45 +110,6 @@ class Bus : public MemObject */ void succeededTiming(Tick busy_time); - /** Function called by the port when the bus is recieving a Atomic - transaction.*/ - Tick recvAtomic(PacketPtr pkt, PortID slave_port_id); - - /** Function called by the port when the bus is recieving an - atomic snoop transaction.*/ - Tick recvAtomicSnoop(PacketPtr pkt, PortID master_port_id); - - /** - * Forward an atomic packet to our snoopers, potentially excluding - * one of the connected coherent masters to avoid sending a packet - * back to where it came from. - * - * @param pkt Packet to forward - * @param exclude_slave_port_id Id of slave port to exclude - * - * @return a pair containing the snoop response and snoop latency - */ - std::pair<MemCmd, Tick> forwardAtomic(PacketPtr pkt, - PortID exclude_slave_port_id); - - /** Function called by the port when the bus is recieving a Functional - transaction.*/ - void recvFunctional(PacketPtr pkt, PortID slave_port_id); - - /** Function called by the port when the bus is recieving a functional - snoop transaction.*/ - void recvFunctionalSnoop(PacketPtr pkt, PortID master_port_id); - - /** - * Forward a functional packet to our snoopers, potentially - * excluding one of the connected coherent masters to avoid - * sending a packet back to where it came from. - * - * @param pkt Packet to forward - * @param exclude_slave_port_id Id of slave port to exclude - */ - void forwardFunctional(PacketPtr pkt, PortID exclude_slave_port_id); - /** Timing function called by port when it is once again able to process * requests. */ void recvRetry(); @@ -392,13 +189,6 @@ class Bus : public MemObject */ AddrRangeList getAddrRanges(); - /** - * Determine if the bus port is snooping or not. - * - * @return a boolean indicating if this port is snooping or not - */ - bool isSnooping() const; - /** Calculate the timing parameters for the packet. Updates the * firstWordTime and finishTime fields of the packet object. * Returns the tick at which the packet header is completed (which @@ -430,7 +220,7 @@ class Bus : public MemObject unsigned findBlockSize(); // event used to schedule a release of the bus - EventWrapper<Bus, &Bus::releaseBus> busIdleEvent; + EventWrapper<BaseBus, &BaseBus::releaseBus> busIdleEvent; bool inRetry; std::set<PortID> inRecvRangeChange; @@ -439,8 +229,11 @@ class Bus : public MemObject std::vector<SlavePort*> slavePorts; std::vector<MasterPort*> masterPorts; + /** Convenience typedefs. */ typedef std::vector<SlavePort*>::iterator SlavePortIter; + typedef std::vector<MasterPort*>::iterator MasterPortIter; typedef std::vector<SlavePort*>::const_iterator SlavePortConstIter; + typedef std::vector<MasterPort*>::const_iterator MasterPortConstIter; /** An array of pointers to ports that retry should be called on because the * original send failed for whatever reason.*/ @@ -478,18 +271,20 @@ class Bus : public MemObject unsigned cachedBlockSize; bool cachedBlockSizeValid; + BaseBus(const BaseBusParams *p); + + virtual ~BaseBus(); + public: /** A function used to return the port associated with this bus object. */ virtual MasterPort& getMasterPort(const std::string& if_name, int idx = -1); virtual SlavePort& getSlavePort(const std::string& if_name, int idx = -1); - virtual void init(); virtual void startup(); unsigned int drain(Event *de); - Bus(const BusParams *p); }; #endif //__MEM_BUS_HH__ diff --git a/src/mem/coherent_bus.cc b/src/mem/coherent_bus.cc new file mode 100644 index 000000000..b40e84762 --- /dev/null +++ b/src/mem/coherent_bus.cc @@ -0,0 +1,493 @@ +/* + * Copyright (c) 2011-2012 ARM Limited + * All rights reserved + * + * The license below extends only to copyright in the software and shall + * not be construed as granting a license to any other intellectual + * property including but not limited to intellectual property relating + * to a hardware implementation of the functionality of the software + * licensed hereunder. You may use the software subject to the license + * terms below provided that you ensure that this notice is replicated + * unmodified and in its entirety in all distributions of the software, + * modified or unmodified, in source code or in binary form. + * + * Copyright (c) 2006 The Regents of The University of Michigan + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer; + * redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution; + * neither the name of the copyright holders nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * Authors: Ali Saidi + * Andreas Hansson + * William Wang + */ + +/** + * @file + * Definition of a bus object. + */ + +#include "base/misc.hh" +#include "base/trace.hh" +#include "debug/BusAddrRanges.hh" +#include "debug/CoherentBus.hh" +#include "mem/coherent_bus.hh" + +CoherentBus::CoherentBus(const CoherentBusParams *p) + : BaseBus(p) +{ + // create the ports based on the size of the master and slave + // vector ports, and the presence of the default port, the ports + // are enumerated starting from zero + for (int i = 0; i < p->port_master_connection_count; ++i) { + std::string portName = csprintf("%s-p%d", name(), i); + MasterPort* bp = new CoherentBusMasterPort(portName, *this, i); + masterPorts.push_back(bp); + } + + // see if we have a default slave device connected and if so add + // our corresponding master port + if (p->port_default_connection_count) { + defaultPortID = masterPorts.size(); + std::string portName = csprintf("%s-default", name()); + MasterPort* bp = new CoherentBusMasterPort(portName, *this, + defaultPortID); + masterPorts.push_back(bp); + } + + // create the slave ports, once again starting at zero + for (int i = 0; i < p->port_slave_connection_count; ++i) { + std::string portName = csprintf("%s-p%d", name(), i); + SlavePort* bp = new CoherentBusSlavePort(portName, *this, i); + slavePorts.push_back(bp); + } + + clearPortCache(); +} + +void +CoherentBus::init() +{ + // iterate over our slave ports and determine which of our + // neighbouring master ports are snooping and add them as snoopers + for (SlavePortConstIter p = slavePorts.begin(); p != slavePorts.end(); + ++p) { + if ((*p)->getMasterPort().isSnooping()) { + DPRINTF(BusAddrRanges, "Adding snooping master %s\n", + (*p)->getMasterPort().name()); + snoopPorts.push_back(*p); + } + } + + if (snoopPorts.empty()) + warn("CoherentBus %s has no snooping ports attached!\n", name()); +} + +bool +CoherentBus::recvTimingReq(PacketPtr pkt, PortID slave_port_id) +{ + // determine the source port based on the id + SlavePort *src_port = slavePorts[slave_port_id]; + + // test if the bus should be considered occupied for the current + // port, and exclude express snoops from the check + if (!pkt->isExpressSnoop() && isOccupied(src_port)) { + DPRINTF(CoherentBus, "recvTimingReq: src %s %s 0x%x BUSY\n", + src_port->name(), pkt->cmdString(), pkt->getAddr()); + return false; + } + + DPRINTF(CoherentBus, "recvTimingReq: src %s %s 0x%x\n", + src_port->name(), pkt->cmdString(), pkt->getAddr()); + + // set the source port for routing of the response + pkt->setSrc(slave_port_id); + + Tick headerFinishTime = pkt->isExpressSnoop() ? 0 : calcPacketTiming(pkt); + Tick packetFinishTime = pkt->isExpressSnoop() ? 0 : pkt->finishTime; + + // uncacheable requests need never be snooped + if (!pkt->req->isUncacheable()) { + // the packet is a memory-mapped request and should be + // broadcasted to our snoopers but the source + forwardTiming(pkt, slave_port_id); + } + + // remember if we add an outstanding req so we can undo it if + // necessary, if the packet needs a response, we should add it + // as outstanding and express snoops never fail so there is + // not need to worry about them + bool add_outstanding = !pkt->isExpressSnoop() && pkt->needsResponse(); + + // keep track that we have an outstanding request packet + // matching this request, this is used by the coherency + // mechanism in determining what to do with snoop responses + // (in recvTimingSnoop) + if (add_outstanding) { + // we should never have an exsiting request outstanding + assert(outstandingReq.find(pkt->req) == outstandingReq.end()); + outstandingReq.insert(pkt->req); + } + + // since it is a normal request, determine the destination + // based on the address and attempt to send the packet + bool success = masterPorts[findPort(pkt->getAddr())]->sendTimingReq(pkt); + + if (!success) { + // inhibited packets should never be forced to retry + assert(!pkt->memInhibitAsserted()); + + // if it was added as outstanding and the send failed, then + // erase it again + if (add_outstanding) + outstandingReq.erase(pkt->req); + + DPRINTF(CoherentBus, "recvTimingReq: src %s %s 0x%x RETRY\n", + src_port->name(), pkt->cmdString(), pkt->getAddr()); + + addToRetryList(src_port); + occupyBus(headerFinishTime); + + return false; + } + + succeededTiming(packetFinishTime); + + return true; +} + +bool +CoherentBus::recvTimingResp(PacketPtr pkt, PortID master_port_id) +{ + // determine the source port based on the id + MasterPort *src_port = masterPorts[master_port_id]; + + // test if the bus should be considered occupied for the current + // port + if (isOccupied(src_port)) { + DPRINTF(CoherentBus, "recvTimingResp: src %s %s 0x%x BUSY\n", + src_port->name(), pkt->cmdString(), pkt->getAddr()); + return false; + } + + DPRINTF(CoherentBus, "recvTimingResp: src %s %s 0x%x\n", + src_port->name(), pkt->cmdString(), pkt->getAddr()); + + calcPacketTiming(pkt); + Tick packetFinishTime = pkt->finishTime; + + // the packet is a normal response to a request that we should + // have seen passing through the bus + assert(outstandingReq.find(pkt->req) != outstandingReq.end()); + + // remove it as outstanding + outstandingReq.erase(pkt->req); + + // send the packet to the destination through one of our slave + // ports, as determined by the destination field + bool success M5_VAR_USED = slavePorts[pkt->getDest()]->sendTimingResp(pkt); + + // currently it is illegal to block responses... can lead to + // deadlock + assert(success); + + succeededTiming(packetFinishTime); + + return true; +} + +void +CoherentBus::recvTimingSnoopReq(PacketPtr pkt, PortID master_port_id) +{ + DPRINTF(CoherentBus, "recvTimingSnoopReq: src %s %s 0x%x\n", + masterPorts[master_port_id]->name(), pkt->cmdString(), + pkt->getAddr()); + + // we should only see express snoops from caches + assert(pkt->isExpressSnoop()); + + // set the source port for routing of the response + pkt->setSrc(master_port_id); + + // forward to all snoopers + forwardTiming(pkt, InvalidPortID); + + // a snoop request came from a connected slave device (one of + // our master ports), and if it is not coming from the slave + // device responsible for the address range something is + // wrong, hence there is nothing further to do as the packet + // would be going back to where it came from + assert(master_port_id == findPort(pkt->getAddr())); + + // this is an express snoop and is never forced to retry + assert(!inRetry); +} + +bool +CoherentBus::recvTimingSnoopResp(PacketPtr pkt, PortID slave_port_id) +{ + // determine the source port based on the id + SlavePort* src_port = slavePorts[slave_port_id]; + + // test if the bus should be considered occupied for the current + // port + if (isOccupied(src_port)) { + DPRINTF(CoherentBus, "recvTimingSnoopResp: src %s %s 0x%x BUSY\n", + src_port->name(), pkt->cmdString(), pkt->getAddr()); + return false; + } + + DPRINTF(CoherentBus, "recvTimingSnoop: src %s %s 0x%x\n", + src_port->name(), pkt->cmdString(), pkt->getAddr()); + + // get the destination from the packet + PortID dest = pkt->getDest(); + + // responses are never express snoops + assert(!pkt->isExpressSnoop()); + + calcPacketTiming(pkt); + Tick packetFinishTime = pkt->finishTime; + + // determine if the response is from a snoop request we + // created as the result of a normal request (in which case it + // should be in the outstandingReq), or if we merely forwarded + // someone else's snoop request + if (outstandingReq.find(pkt->req) == outstandingReq.end()) { + // this is a snoop response to a snoop request we + // forwarded, e.g. coming from the L1 and going to the L2 + // this should be forwarded as a snoop response + bool success M5_VAR_USED = masterPorts[dest]->sendTimingSnoopResp(pkt); + assert(success); + } else { + // we got a snoop response on one of our slave ports, + // i.e. from a coherent master connected to the bus, and + // since we created the snoop request as part of + // recvTiming, this should now be a normal response again + outstandingReq.erase(pkt->req); + + // this is a snoop response from a coherent master, with a + // destination field set on its way through the bus as + // request, hence it should never go back to where the + // snoop response came from, but instead to where the + // original request came from + assert(slave_port_id != dest); + + // as a normal response, it should go back to a master + // through one of our slave ports + bool success M5_VAR_USED = slavePorts[dest]->sendTimingResp(pkt); + + // currently it is illegal to block responses... can lead + // to deadlock + assert(success); + } + + succeededTiming(packetFinishTime); + + return true; +} + + +void +CoherentBus::forwardTiming(PacketPtr pkt, PortID exclude_slave_port_id) +{ + for (SlavePortIter s = snoopPorts.begin(); s != snoopPorts.end(); ++s) { + SlavePort *p = *s; + // we could have gotten this request from a snooping master + // (corresponding to our own slave port that is also in + // snoopPorts) and should not send it back to where it came + // from + if (exclude_slave_port_id == InvalidPortID || + p->getId() != exclude_slave_port_id) { + // cache is not allowed to refuse snoop + p->sendTimingSnoopReq(pkt); + } + } +} + +Tick +CoherentBus::recvAtomic(PacketPtr pkt, PortID slave_port_id) +{ + DPRINTF(CoherentBus, "recvAtomic: packet src %s addr 0x%x cmd %s\n", + slavePorts[slave_port_id]->name(), pkt->getAddr(), + pkt->cmdString()); + + MemCmd snoop_response_cmd = MemCmd::InvalidCmd; + Tick snoop_response_latency = 0; + + // uncacheable requests need never be snooped + if (!pkt->req->isUncacheable()) { + // forward to all snoopers but the source + std::pair<MemCmd, Tick> snoop_result = + forwardAtomic(pkt, slave_port_id); + snoop_response_cmd = snoop_result.first; + snoop_response_latency = snoop_result.second; + } + + // even if we had a snoop response, we must continue and also + // perform the actual request at the destination + PortID dest_id = findPort(pkt->getAddr()); + + // forward the request to the appropriate destination + Tick response_latency = masterPorts[dest_id]->sendAtomic(pkt); + + // if we got a response from a snooper, restore it here + if (snoop_response_cmd != MemCmd::InvalidCmd) { + // no one else should have responded + assert(!pkt->isResponse()); + pkt->cmd = snoop_response_cmd; + response_latency = snoop_response_latency; + } + + pkt->finishTime = curTick() + response_latency; + return response_latency; +} + +Tick +CoherentBus::recvAtomicSnoop(PacketPtr pkt, PortID master_port_id) +{ + DPRINTF(CoherentBus, "recvAtomicSnoop: packet src %s addr 0x%x cmd %s\n", + masterPorts[master_port_id]->name(), pkt->getAddr(), + pkt->cmdString()); + + // forward to all snoopers + std::pair<MemCmd, Tick> snoop_result = + forwardAtomic(pkt, InvalidPortID); + MemCmd snoop_response_cmd = snoop_result.first; + Tick snoop_response_latency = snoop_result.second; + + if (snoop_response_cmd != MemCmd::InvalidCmd) + pkt->cmd = snoop_response_cmd; + + pkt->finishTime = curTick() + snoop_response_latency; + return snoop_response_latency; +} + +std::pair<MemCmd, Tick> +CoherentBus::forwardAtomic(PacketPtr pkt, PortID exclude_slave_port_id) +{ + // the packet may be changed on snoops, record the original + // command to enable us to restore it between snoops so that + // additional snoops can take place properly + MemCmd orig_cmd = pkt->cmd; + MemCmd snoop_response_cmd = MemCmd::InvalidCmd; + Tick snoop_response_latency = 0; + + for (SlavePortIter s = snoopPorts.begin(); s != snoopPorts.end(); ++s) { + SlavePort *p = *s; + // we could have gotten this request from a snooping master + // (corresponding to our own slave port that is also in + // snoopPorts) and should not send it back to where it came + // from + if (exclude_slave_port_id == InvalidPortID || + p->getId() != exclude_slave_port_id) { + Tick latency = p->sendAtomicSnoop(pkt); + // in contrast to a functional access, we have to keep on + // going as all snoopers must be updated even if we get a + // response + if (pkt->isResponse()) { + // response from snoop agent + assert(pkt->cmd != orig_cmd); + assert(pkt->memInhibitAsserted()); + // should only happen once + assert(snoop_response_cmd == MemCmd::InvalidCmd); + // save response state + snoop_response_cmd = pkt->cmd; + snoop_response_latency = latency; + // restore original packet state for remaining snoopers + pkt->cmd = orig_cmd; + } + } + } + + // the packet is restored as part of the loop and any potential + // snoop response is part of the returned pair + return std::make_pair(snoop_response_cmd, snoop_response_latency); +} + +void +CoherentBus::recvFunctional(PacketPtr pkt, PortID slave_port_id) +{ + if (!pkt->isPrint()) { + // don't do DPRINTFs on PrintReq as it clutters up the output + DPRINTF(CoherentBus, + "recvFunctional: packet src %s addr 0x%x cmd %s\n", + slavePorts[slave_port_id]->name(), pkt->getAddr(), + pkt->cmdString()); + } + + // uncacheable requests need never be snooped + if (!pkt->req->isUncacheable()) { + // forward to all snoopers but the source + forwardFunctional(pkt, slave_port_id); + } + + // there is no need to continue if the snooping has found what we + // were looking for and the packet is already a response + if (!pkt->isResponse()) { + PortID dest_id = findPort(pkt->getAddr()); + + masterPorts[dest_id]->sendFunctional(pkt); + } +} + +void +CoherentBus::recvFunctionalSnoop(PacketPtr pkt, PortID master_port_id) +{ + if (!pkt->isPrint()) { + // don't do DPRINTFs on PrintReq as it clutters up the output + DPRINTF(CoherentBus, + "recvFunctionalSnoop: packet src %s addr 0x%x cmd %s\n", + masterPorts[master_port_id]->name(), pkt->getAddr(), + pkt->cmdString()); + } + + // forward to all snoopers + forwardFunctional(pkt, InvalidPortID); +} + +void +CoherentBus::forwardFunctional(PacketPtr pkt, PortID exclude_slave_port_id) +{ + for (SlavePortIter s = snoopPorts.begin(); s != snoopPorts.end(); ++s) { + SlavePort *p = *s; + // we could have gotten this request from a snooping master + // (corresponding to our own slave port that is also in + // snoopPorts) and should not send it back to where it came + // from + if (exclude_slave_port_id == InvalidPortID || + p->getId() != exclude_slave_port_id) + p->sendFunctionalSnoop(pkt); + + // if we get a response we are done + if (pkt->isResponse()) { + break; + } + } +} + +CoherentBus * +CoherentBusParams::create() +{ + return new CoherentBus(this); +} diff --git a/src/mem/coherent_bus.hh b/src/mem/coherent_bus.hh new file mode 100644 index 000000000..760ff8add --- /dev/null +++ b/src/mem/coherent_bus.hh @@ -0,0 +1,290 @@ +/* + * Copyright (c) 2011-2012 ARM Limited + * All rights reserved + * + * The license below extends only to copyright in the software and shall + * not be construed as granting a license to any other intellectual + * property including but not limited to intellectual property relating + * to a hardware implementation of the functionality of the software + * licensed hereunder. You may use the software subject to the license + * terms below provided that you ensure that this notice is replicated + * unmodified and in its entirety in all distributions of the software, + * modified or unmodified, in source code or in binary form. + * + * Copyright (c) 2002-2005 The Regents of The University of Michigan + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer; + * redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution; + * neither the name of the copyright holders nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * Authors: Ron Dreslinski + * Ali Saidi + * Andreas Hansson + * William Wang + */ + +/** + * @file + * Declaration of a coherent bus. + */ + +#ifndef __MEM_COHERENT_BUS_HH__ +#define __MEM_COHERENT_BUS_HH__ + +#include "mem/bus.hh" +#include "params/CoherentBus.hh" + +/** + * A coherent bus connects a number of (potentially) snooping masters + * and slaves, and routes the request and response packets based on + * the address, and also forwards all requests to the snoopers and + * deals with the snoop responses. + * + * The coherent bus can be used as a template for modelling QPI, +* HyperTransport, ACE and coherent OCP buses, and is typically used + * for the L1-to-L2 buses and as the main system interconnect. + */ +class CoherentBus : public BaseBus +{ + + protected: + + /** + * Declaration of the coherent bus slave port type, one will be + * instantiated for each of the master ports connecting to the + * bus. + */ + class CoherentBusSlavePort : public SlavePort + { + + private: + + /** A reference to the bus to which this port belongs. */ + CoherentBus &bus; + + public: + + CoherentBusSlavePort(const std::string &_name, + CoherentBus &_bus, PortID _id) + : SlavePort(_name, &_bus, _id), bus(_bus) + { } + + protected: + + /** + * When receiving a timing request, pass it to the bus. + */ + virtual bool recvTimingReq(PacketPtr pkt) + { return bus.recvTimingReq(pkt, id); } + + /** + * When receiving a timing snoop response, pass it to the bus. + */ + virtual bool recvTimingSnoopResp(PacketPtr pkt) + { return bus.recvTimingSnoopResp(pkt, id); } + + /** + * When receiving an atomic request, pass it to the bus. + */ + virtual Tick recvAtomic(PacketPtr pkt) + { return bus.recvAtomic(pkt, id); } + + /** + * When receiving a functional request, pass it to the bus. + */ + virtual void recvFunctional(PacketPtr pkt) + { bus.recvFunctional(pkt, id); } + + /** + * When receiving a retry, pass it to the bus. + */ + virtual void recvRetry() + { panic("Bus slave ports always succeed and should never retry.\n"); } + + /** + * Return the union of all adress ranges seen by this bus. + */ + virtual AddrRangeList getAddrRanges() + { return bus.getAddrRanges(); } + + /** + * Get the maximum block size as seen by the bus. + */ + virtual unsigned deviceBlockSize() const + { return bus.findBlockSize(); } + + }; + + /** + * Declaration of the coherent bus master port type, one will be + * instantiated for each of the slave interfaces connecting to the + * bus. + */ + class CoherentBusMasterPort : public MasterPort + { + private: + /** A reference to the bus to which this port belongs. */ + CoherentBus &bus; + + public: + + CoherentBusMasterPort(const std::string &_name, + CoherentBus &_bus, PortID _id) + : MasterPort(_name, &_bus, _id), bus(_bus) + { } + + protected: + + /** + * Determine if this port should be considered a snooper. For + * a coherent bus master port this is always true. + * + * @return a boolean that is true if this port is snooping + */ + virtual bool isSnooping() const + { return true; } + + /** + * When receiving a timing response, pass it to the bus. + */ + virtual bool recvTimingResp(PacketPtr pkt) + { return bus.recvTimingResp(pkt, id); } + + /** + * When receiving a timing snoop request, pass it to the bus. + */ + virtual void recvTimingSnoopReq(PacketPtr pkt) + { return bus.recvTimingSnoopReq(pkt, id); } + + /** + * When receiving an atomic snoop request, pass it to the bus. + */ + virtual Tick recvAtomicSnoop(PacketPtr pkt) + { return bus.recvAtomicSnoop(pkt, id); } + + /** + * When receiving a functional snoop request, pass it to the bus. + */ + virtual void recvFunctionalSnoop(PacketPtr pkt) + { bus.recvFunctionalSnoop(pkt, id); } + + /** When reciving a range change from the peer port (at id), + pass it to the bus. */ + virtual void recvRangeChange() + { bus.recvRangeChange(id); } + + /** When reciving a retry from the peer port (at id), + pass it to the bus. */ + virtual void recvRetry() + { bus.recvRetry(); } + + // Ask the bus to ask everyone on the bus what their block size is and + // take the max of it. This might need to be changed a bit if we ever + // support multiple block sizes. + virtual unsigned deviceBlockSize() const + { return bus.findBlockSize(); } + + }; + + std::vector<SlavePort*> snoopPorts; + + /** + * Store the outstanding requests so we can determine which ones + * we generated and which ones were merely forwarded. This is used + * in the coherent bus when coherency responses come back. + */ + std::set<RequestPtr> outstandingReq; + + /** Function called by the port when the bus is recieving a Timing + request packet.*/ + bool recvTimingReq(PacketPtr pkt, PortID slave_port_id); + + /** Function called by the port when the bus is recieving a Timing + response packet.*/ + bool recvTimingResp(PacketPtr pkt, PortID master_port_id); + + /** Function called by the port when the bus is recieving a timing + snoop request.*/ + void recvTimingSnoopReq(PacketPtr pkt, PortID master_port_id); + + /** Function called by the port when the bus is recieving a timing + snoop response.*/ + bool recvTimingSnoopResp(PacketPtr pkt, PortID slave_port_id); + + /** + * Forward a timing packet to our snoopers, potentially excluding + * one of the connected coherent masters to avoid sending a packet + * back to where it came from. + * + * @param pkt Packet to forward + * @param exclude_slave_port_id Id of slave port to exclude + */ + void forwardTiming(PacketPtr pkt, PortID exclude_slave_port_id); + + /** Function called by the port when the bus is recieving a Atomic + transaction.*/ + Tick recvAtomic(PacketPtr pkt, PortID slave_port_id); + + /** Function called by the port when the bus is recieving an + atomic snoop transaction.*/ + Tick recvAtomicSnoop(PacketPtr pkt, PortID master_port_id); + + /** + * Forward an atomic packet to our snoopers, potentially excluding + * one of the connected coherent masters to avoid sending a packet + * back to where it came from. + * + * @param pkt Packet to forward + * @param exclude_slave_port_id Id of slave port to exclude + * + * @return a pair containing the snoop response and snoop latency + */ + std::pair<MemCmd, Tick> forwardAtomic(PacketPtr pkt, + PortID exclude_slave_port_id); + + /** Function called by the port when the bus is recieving a Functional + transaction.*/ + void recvFunctional(PacketPtr pkt, PortID slave_port_id); + + /** Function called by the port when the bus is recieving a functional + snoop transaction.*/ + void recvFunctionalSnoop(PacketPtr pkt, PortID master_port_id); + + /** + * Forward a functional packet to our snoopers, potentially + * excluding one of the connected coherent masters to avoid + * sending a packet back to where it came from. + * + * @param pkt Packet to forward + * @param exclude_slave_port_id Id of slave port to exclude + */ + void forwardFunctional(PacketPtr pkt, PortID exclude_slave_port_id); + + public: + + virtual void init(); + + CoherentBus(const CoherentBusParams *p); +}; + +#endif //__MEM_COHERENT_BUS_HH__ diff --git a/src/mem/noncoherent_bus.cc b/src/mem/noncoherent_bus.cc new file mode 100644 index 000000000..4faad757a --- /dev/null +++ b/src/mem/noncoherent_bus.cc @@ -0,0 +1,209 @@ +/* + * Copyright (c) 2011-2012 ARM Limited + * All rights reserved + * + * The license below extends only to copyright in the software and shall + * not be construed as granting a license to any other intellectual + * property including but not limited to intellectual property relating + * to a hardware implementation of the functionality of the software + * licensed hereunder. You may use the software subject to the license + * terms below provided that you ensure that this notice is replicated + * unmodified and in its entirety in all distributions of the software, + * modified or unmodified, in source code or in binary form. + * + * Copyright (c) 2006 The Regents of The University of Michigan + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer; + * redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution; + * neither the name of the copyright holders nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * Authors: Ali Saidi + * Andreas Hansson + * William Wang + */ + +/** + * @file + * Definition of a bus object. + */ + +#include "base/misc.hh" +#include "base/trace.hh" +#include "debug/Bus.hh" +#include "debug/BusAddrRanges.hh" +#include "debug/NoncoherentBus.hh" +#include "mem/noncoherent_bus.hh" + +NoncoherentBus::NoncoherentBus(const NoncoherentBusParams *p) + : BaseBus(p) +{ + // create the ports based on the size of the master and slave + // vector ports, and the presence of the default port, the ports + // are enumerated starting from zero + for (int i = 0; i < p->port_master_connection_count; ++i) { + std::string portName = csprintf("%s-p%d", name(), i); + MasterPort* bp = new NoncoherentBusMasterPort(portName, *this, i); + masterPorts.push_back(bp); + } + + // see if we have a default slave device connected and if so add + // our corresponding master port + if (p->port_default_connection_count) { + defaultPortID = masterPorts.size(); + std::string portName = csprintf("%s-default", name()); + MasterPort* bp = new NoncoherentBusMasterPort(portName, *this, + defaultPortID); + masterPorts.push_back(bp); + } + + // create the slave ports, once again starting at zero + for (int i = 0; i < p->port_slave_connection_count; ++i) { + std::string portName = csprintf("%s-p%d", name(), i); + SlavePort* bp = new NoncoherentBusSlavePort(portName, *this, i); + slavePorts.push_back(bp); + } + + clearPortCache(); +} + +bool +NoncoherentBus::recvTimingReq(PacketPtr pkt, PortID slave_port_id) +{ + // determine the source port based on the id + SlavePort *src_port = slavePorts[slave_port_id]; + + // we should never see express snoops on a non-coherent bus + assert(!pkt->isExpressSnoop()); + + // test if the bus should be considered occupied for the current + // port + if (isOccupied(src_port)) { + DPRINTF(NoncoherentBus, "recvTimingReq: src %s %s 0x%x BUSY\n", + src_port->name(), pkt->cmdString(), pkt->getAddr()); + return false; + } + + DPRINTF(NoncoherentBus, "recvTimingReq: src %s %s 0x%x\n", + src_port->name(), pkt->cmdString(), pkt->getAddr()); + + // set the source port for routing of the response + pkt->setSrc(slave_port_id); + + Tick headerFinishTime = calcPacketTiming(pkt); + Tick packetFinishTime = pkt->finishTime; + + // since it is a normal request, determine the destination + // based on the address and attempt to send the packet + bool success = masterPorts[findPort(pkt->getAddr())]->sendTimingReq(pkt); + + if (!success) { + // inhibited packets should never be forced to retry + assert(!pkt->memInhibitAsserted()); + + DPRINTF(NoncoherentBus, "recvTimingReq: src %s %s 0x%x RETRY\n", + src_port->name(), pkt->cmdString(), pkt->getAddr()); + + addToRetryList(src_port); + occupyBus(headerFinishTime); + + return false; + } + + succeededTiming(packetFinishTime); + + return true; +} + +bool +NoncoherentBus::recvTimingResp(PacketPtr pkt, PortID master_port_id) +{ + // determine the source port based on the id + MasterPort *src_port = masterPorts[master_port_id]; + + // test if the bus should be considered occupied for the current + // port + if (isOccupied(src_port)) { + DPRINTF(NoncoherentBus, "recvTimingResp: src %s %s 0x%x BUSY\n", + src_port->name(), pkt->cmdString(), pkt->getAddr()); + return false; + } + + DPRINTF(NoncoherentBus, "recvTimingResp: src %s %s 0x%x\n", + src_port->name(), pkt->cmdString(), pkt->getAddr()); + + calcPacketTiming(pkt); + Tick packetFinishTime = pkt->finishTime; + + // send the packet to the destination through one of our slave + // ports, as determined by the destination field + bool success M5_VAR_USED = slavePorts[pkt->getDest()]->sendTimingResp(pkt); + + // currently it is illegal to block responses... can lead to + // deadlock + assert(success); + + succeededTiming(packetFinishTime); + + return true; +} + +Tick +NoncoherentBus::recvAtomic(PacketPtr pkt, PortID slave_port_id) +{ + DPRINTF(NoncoherentBus, "recvAtomic: packet src %s addr 0x%x cmd %s\n", + slavePorts[slave_port_id]->name(), pkt->getAddr(), + pkt->cmdString()); + + // determine the destination port + PortID dest_id = findPort(pkt->getAddr()); + + // forward the request to the appropriate destination + Tick response_latency = masterPorts[dest_id]->sendAtomic(pkt); + + pkt->finishTime = curTick() + response_latency; + return response_latency; +} + +void +NoncoherentBus::recvFunctional(PacketPtr pkt, PortID slave_port_id) +{ + if (!pkt->isPrint()) { + // don't do DPRINTFs on PrintReq as it clutters up the output + DPRINTF(NoncoherentBus, + "recvFunctional: packet src %s addr 0x%x cmd %s\n", + slavePorts[slave_port_id]->name(), pkt->getAddr(), + pkt->cmdString()); + } + + // determine the destination port + PortID dest_id = findPort(pkt->getAddr()); + + // forward the request to the appropriate destination + masterPorts[dest_id]->sendFunctional(pkt); +} + +NoncoherentBus* +NoncoherentBusParams::create() +{ + return new NoncoherentBus(this); +} diff --git a/src/mem/noncoherent_bus.hh b/src/mem/noncoherent_bus.hh new file mode 100644 index 000000000..8bd6c0e74 --- /dev/null +++ b/src/mem/noncoherent_bus.hh @@ -0,0 +1,201 @@ +/* + * Copyright (c) 2011-2012 ARM Limited + * All rights reserved + * + * The license below extends only to copyright in the software and shall + * not be construed as granting a license to any other intellectual + * property including but not limited to intellectual property relating + * to a hardware implementation of the functionality of the software + * licensed hereunder. You may use the software subject to the license + * terms below provided that you ensure that this notice is replicated + * unmodified and in its entirety in all distributions of the software, + * modified or unmodified, in source code or in binary form. + * + * Copyright (c) 2002-2005 The Regents of The University of Michigan + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer; + * redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution; + * neither the name of the copyright holders nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * Authors: Ron Dreslinski + * Ali Saidi + * Andreas Hansson + * William Wang + */ + +/** + * @file + * Declaration of a non-coherent bus. + */ + +#ifndef __MEM_NONCOHERENT_BUS_HH__ +#define __MEM_NONCOHERENT_BUS_HH__ + +#include "mem/bus.hh" +#include "params/NoncoherentBus.hh" + +/** + * A non-coherent bus connects a number of non-snooping masters and + * slaves, and routes the request and response packets based on the + * address. The request packets issued by the master connected to a + * non-coherent bus could still snoop in caches attached to a coherent + * bus, as is the case with the I/O bus and memory bus in most system + * configurations. No snoops will, however, reach any master on the + * non-coherent bus itself. + * + * The non-coherent bus can be used as a template for modelling PCI, + * PCIe, and non-coherent AMBA and OCP buses, and is typically used + * for the I/O buses. + */ +class NoncoherentBus : public BaseBus +{ + + protected: + + /** + * Declaration of the non-coherent bus slave port type, one will + * be instantiated for each of the master ports connecting to the + * bus. + */ + class NoncoherentBusSlavePort : public SlavePort + { + private: + + /** A reference to the bus to which this port belongs. */ + NoncoherentBus &bus; + + public: + + NoncoherentBusSlavePort(const std::string &_name, + NoncoherentBus &_bus, PortID _id) + : SlavePort(_name, &_bus, _id), bus(_bus) + { } + + protected: + + /** + * When receiving a timing request, pass it to the bus. + */ + virtual bool recvTimingReq(PacketPtr pkt) + { return bus.recvTimingReq(pkt, id); } + + /** + * When receiving an atomic request, pass it to the bus. + */ + virtual Tick recvAtomic(PacketPtr pkt) + { return bus.recvAtomic(pkt, id); } + + /** + * When receiving a functional request, pass it to the bus. + */ + virtual void recvFunctional(PacketPtr pkt) + { bus.recvFunctional(pkt, id); } + + /** + * When receiving a retry, pass it to the bus. + */ + virtual void recvRetry() + { panic("Bus slave ports always succeed and should never retry.\n"); } + + /** + * Return the union of all adress ranges seen by this bus. + */ + virtual AddrRangeList getAddrRanges() + { return bus.getAddrRanges(); } + + /** + * Get the maximum block size as seen by the bus. + */ + virtual unsigned deviceBlockSize() const + { return bus.findBlockSize(); } + + }; + + /** + * Declaration of the bus master port type, one will be + * instantiated for each of the slave ports connecting to the + * bus. + */ + class NoncoherentBusMasterPort : public MasterPort + { + private: + + /** A reference to the bus to which this port belongs. */ + NoncoherentBus &bus; + + public: + + NoncoherentBusMasterPort(const std::string &_name, + NoncoherentBus &_bus, PortID _id) + : MasterPort(_name, &_bus, _id), bus(_bus) + { } + + protected: + + /** + * When receiving a timing response, pass it to the bus. + */ + virtual bool recvTimingResp(PacketPtr pkt) + { return bus.recvTimingResp(pkt, id); } + + /** When reciving a range change from the peer port (at id), + pass it to the bus. */ + virtual void recvRangeChange() + { bus.recvRangeChange(id); } + + /** When reciving a retry from the peer port (at id), + pass it to the bus. */ + virtual void recvRetry() + { bus.recvRetry(); } + + /** + * Get the maximum block size as seen by the bus. + */ + virtual unsigned deviceBlockSize() const + { return bus.findBlockSize(); } + + }; + + /** Function called by the port when the bus is recieving a Timing + request packet.*/ + bool recvTimingReq(PacketPtr pkt, PortID slave_port_id); + + /** Function called by the port when the bus is recieving a Timing + response packet.*/ + bool recvTimingResp(PacketPtr pkt, PortID master_port_id); + + /** Function called by the port when the bus is recieving a Atomic + transaction.*/ + Tick recvAtomic(PacketPtr pkt, PortID slave_port_id); + + /** Function called by the port when the bus is recieving a Functional + transaction.*/ + void recvFunctional(PacketPtr pkt, PortID slave_port_id); + + public: + + NoncoherentBus(const NoncoherentBusParams *p); + +}; + +#endif //__MEM_NONCOHERENT_BUS_HH__ |