summaryrefslogtreecommitdiff
path: root/src/mem/bus.cc
diff options
context:
space:
mode:
Diffstat (limited to 'src/mem/bus.cc')
-rw-r--r--src/mem/bus.cc492
1 files changed, 34 insertions, 458 deletions
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);
-}