*/
+#include <limits>
+
#include "base/misc.hh"
#include "base/trace.hh"
#include "mem/bus.hh"
Port *
Bus::getPort(const std::string &if_name, int idx)
{
- if (if_name == "default")
+ if (if_name == "default") {
if (defaultPort == NULL) {
defaultPort = new BusPort(csprintf("%s-default",name()), this,
- defaultId);
+ defaultId);
return defaultPort;
} else
fatal("Default port already set\n");
+ }
// if_name ignored? forced to be empty?
- int id = interfaces.size();
+ int id = maxId++;
+ assert(maxId < std::numeric_limits<typeof(maxId)>::max());
BusPort *bp = new BusPort(csprintf("%s-p%d", name(), id), this, id);
- interfaces.push_back(bp);
+ interfaces[id] = bp;
return bp;
}
+void
+Bus::deletePortRefs(Port *p)
+{
+ BusPort *bp = dynamic_cast<BusPort*>(p);
+ if (bp == NULL)
+ panic("Couldn't convert Port* to BusPort*\n");
+ interfaces.erase(bp->getId());
+}
+
/** Get the ranges of anyone other buses that we are connected to. */
void
Bus::init()
{
- std::vector<Port*>::iterator intIter;
+ m5::hash_map<short,BusPort*>::iterator intIter;
for (intIter = interfaces.begin(); intIter != interfaces.end(); intIter++)
- (*intIter)->sendStatusChange(Port::RangeChange);
+ intIter->second->sendStatusChange(Port::RangeChange);
}
Bus::BusFreeEvent::BusFreeEvent(Bus *_bus) : Event(&mainEventQueue), bus(_bus)
return "bus became available";
}
-/** Function called by the port when the bus is receiving a Timing
- * transaction.*/
-bool
-Bus::recvTiming(Packet *pkt)
+void Bus::occupyBus(PacketPtr pkt)
{
- Port *port;
- DPRINTF(Bus, "recvTiming: packet src %d dest %d addr 0x%x cmd %s\n",
- pkt->getSrc(), pkt->getDest(), pkt->getAddr(), pkt->cmdString());
-
- Port *pktPort = interfaces[pkt->getSrc()];
-
- // If the bus is busy, or other devices are in line ahead of the current
- // one, put this device on the retry list.
- if (tickNextIdle > curTick ||
- (retryList.size() && (!inRetry || pktPort != retryList.front()))) {
- DPRINTF(Bus, "Adding RETRY for %i\n", pktPort);
- addToRetryList(pktPort);
- return false;
- }
-
- short dest = pkt->getDest();
- if (dest == Packet::Broadcast) {
- if (timingSnoop(pkt)) {
- pkt->flags |= SNOOP_COMMIT;
- bool success = timingSnoop(pkt);
- assert(success);
- if (pkt->flags & SATISFIED) {
- //Cache-Cache transfer occuring
- if (inRetry) {
- DPRINTF(Bus, "Removing RETRY %i\n", retryList.front());
- retryList.pop_front();
- inRetry = false;
- }
- return true;
- }
- port = findPort(pkt->getAddr(), pkt->getSrc());
- } else {
- //Snoop didn't succeed
- DPRINTF(Bus, "Snoop caused adding to RETRY list %i\n", pktPort);
- addToRetryList(pktPort);
- return false;
- }
- } else {
- assert(dest >= 0 && dest < interfaces.size());
- assert(dest != pkt->getSrc()); // catch infinite loops
- port = interfaces[dest];
- }
-
//Bring tickNextIdle up to the present tick
//There is some potential ambiguity where a cycle starts, which might make
//a difference when devices are acting right around a cycle boundary. Using
// The bus will become idle once the current packet is delivered.
pkt->finishTime = tickNextIdle;
+}
- if (port->sendTiming(pkt)) {
- // Packet was successfully sent. Return true.
- // Also take care of retries
- if (inRetry) {
- DPRINTF(Bus, "Remove retry from list %i\n", retryList.front());
- retryList.pop_front();
- inRetry = false;
+/** Function called by the port when the bus is receiving a Timing
+ * transaction.*/
+bool
+Bus::recvTiming(PacketPtr pkt)
+{
+ Port *port;
+ DPRINTF(Bus, "recvTiming: packet src %d dest %d addr 0x%x cmd %s\n",
+ pkt->getSrc(), pkt->getDest(), pkt->getAddr(), pkt->cmdString());
+
+ BusPort *pktPort;
+ if (pkt->getSrc() == defaultId)
+ pktPort = defaultPort;
+ else pktPort = interfaces[pkt->getSrc()];
+
+ // If the bus is busy, or other devices are in line ahead of the current
+ // one, put this device on the retry list.
+ if (tickNextIdle > curTick ||
+ (retryList.size() && (!inRetry || pktPort != retryList.front()))) {
+ addToRetryList(pktPort);
+ return false;
+ }
+
+ short dest = pkt->getDest();
+ if (dest == Packet::Broadcast) {
+ port = findPort(pkt->getAddr(), pkt->getSrc());
+ if (timingSnoop(pkt, port ? port : interfaces[pkt->getSrc()])) {
+ bool success;
+
+ pkt->flags |= SNOOP_COMMIT;
+ success = timingSnoop(pkt, port ? port : interfaces[pkt->getSrc()]);
+ assert(success);
+
+ if (pkt->flags & SATISFIED) {
+ //Cache-Cache transfer occuring
+ if (inRetry) {
+ retryList.front()->onRetryList(false);
+ retryList.pop_front();
+ inRetry = false;
+ }
+ occupyBus(pkt);
+ return true;
+ }
+ } else {
+ //Snoop didn't succeed
+ DPRINTF(Bus, "Adding a retry to RETRY list %d\n",
+ pktPort->getId());
+ addToRetryList(pktPort);
+ return false;
}
- return true;
+ } else {
+ assert(dest >= 0 && dest < maxId);
+ assert(dest != pkt->getSrc()); // catch infinite loops
+ port = interfaces[dest];
}
- // Packet not successfully sent. Leave or put it on the retry list.
- DPRINTF(Bus, "Adding a retry to RETRY list %i\n", pktPort);
- addToRetryList(pktPort);
- return false;
+ occupyBus(pkt);
+
+ if (port) {
+ if (port->sendTiming(pkt)) {
+ // Packet was successfully sent. Return true.
+ // Also take care of retries
+ if (inRetry) {
+ DPRINTF(Bus, "Remove retry from list %d\n",
+ retryList.front()->getId());
+ retryList.front()->onRetryList(false);
+ retryList.pop_front();
+ inRetry = false;
+ }
+ return true;
+ }
+
+ // Packet not successfully sent. Leave or put it on the retry list.
+ DPRINTF(Bus, "Adding a retry to RETRY list %d\n",
+ pktPort->getId());
+ addToRetryList(pktPort);
+ return false;
+ }
+ else {
+ //Forwarding up from responder, just return true;
+ return true;
+ }
}
void
Bus::recvRetry(int id)
{
DPRINTF(Bus, "Received a retry\n");
- // If there's anything waiting...
- if (retryList.size()) {
+ // If there's anything waiting, and the bus isn't busy...
+ if (retryList.size() && curTick >= tickNextIdle) {
//retryingPort = retryList.front();
inRetry = true;
DPRINTF(Bus, "Sending a retry\n");
retryList.front()->sendRetry();
// If inRetry is still true, sendTiming wasn't called
if (inRetry)
- panic("Port %s didn't call sendTiming in it's recvRetry\n",\
- retryList.front()->getPeer()->name());
- //assert(!inRetry);
+ {
+ retryList.front()->onRetryList(false);
+ retryList.pop_front();
+ inRetry = false;
+
+ //Bring tickNextIdle up to the present
+ while (tickNextIdle < curTick)
+ tickNextIdle += clock;
+
+ //Burn a cycle for the missed grant.
+ tickNextIdle += clock;
+
+ if (!busIdle.scheduled()) {
+ busIdle.schedule(tickNextIdle);
+ } else {
+ busIdle.reschedule(tickNextIdle);
+ }
+ }
+ }
+ //If we weren't able to drain before, we might be able to now.
+ if (drainEvent && retryList.size() == 0 && curTick >= tickNextIdle) {
+ drainEvent->process();
+ // Clear the drain event once we're done with it.
+ drainEvent = NULL;
}
}
{
/* An interval tree would be a better way to do this. --ali. */
int dest_id = -1;
- int i = 0;
- bool found = false;
AddrRangeIter iter;
+ range_map<Addr,int>::iterator i;
- while (i < portList.size() && !found)
- {
- if (portList[i].range == addr) {
- dest_id = portList[i].portId;
- found = true;
- DPRINTF(Bus, " found addr %#llx on device %d\n", addr, dest_id);
- }
- i++;
- }
+ i = portMap.find(RangeSize(addr,1));
+ if (i != portMap.end())
+ dest_id = i->second;
// Check if this matches the default range
if (dest_id == -1) {
return defaultPort;
}
}
- panic("Unable to find destination for addr: %#llx", addr);
+
+ if (responderSet) {
+ panic("Unable to find destination for addr (user set default "
+ "responder): %#llx", addr);
+ } else {
+ DPRINTF(Bus, "Unable to find destination for addr: %#llx, will use "
+ "default port", addr);
+
+ return defaultPort;
+ }
}
// we shouldn't be sending this back to where it came from
- assert(dest_id != id);
+ // do the snoop access and then we should terminate
+ // the cyclical call.
+ if (dest_id == id)
+ return 0;
return interfaces[dest_id];
}
if (portSnoopList[i].range == addr && portSnoopList[i].portId != id) {
//Careful to not overlap ranges
//or snoop will be called more than once on the port
- ports.push_back(portSnoopList[i].portId);
+
+ //@todo Fix this hack because ranges are overlapping
+ //need to make sure we dont't create overlapping ranges
+ bool hack_overlap = false;
+ int size = ports.size();
+ for (int j=0; j < size; j++) {
+ if (ports[j] == portSnoopList[i].portId)
+ hack_overlap = true;
+ }
+
+ if (!hack_overlap)
+ ports.push_back(portSnoopList[i].portId);
// DPRINTF(Bus, " found snoop addr %#llx on device%d\n", addr,
// portSnoopList[i].portId);
}
return ports;
}
-void
-Bus::atomicSnoop(Packet *pkt)
+Tick
+Bus::atomicSnoop(PacketPtr pkt, Port *responder)
{
std::vector<int> ports = findSnoopPorts(pkt->getAddr(), pkt->getSrc());
+ Tick response_time = 0;
while (!ports.empty())
{
- interfaces[ports.back()]->sendAtomic(pkt);
+ if (interfaces[ports.back()] != responder) {
+ Tick response = interfaces[ports.back()]->sendAtomic(pkt);
+ if (response) {
+ assert(!response_time); //Multiple responders
+ response_time = response;
+ }
+ }
ports.pop_back();
}
+ return response_time;
}
void
-Bus::functionalSnoop(Packet *pkt)
+Bus::functionalSnoop(PacketPtr pkt, Port *responder)
{
std::vector<int> ports = findSnoopPorts(pkt->getAddr(), pkt->getSrc());
- while (!ports.empty())
+ //The packet may be changed by another bus on snoops, restore the id after each
+ int id = pkt->getSrc();
+ while (!ports.empty() && pkt->result != Packet::Success)
{
- interfaces[ports.back()]->sendFunctional(pkt);
+ if (interfaces[ports.back()] != responder)
+ interfaces[ports.back()]->sendFunctional(pkt);
ports.pop_back();
+ pkt->setSrc(id);
}
}
bool
-Bus::timingSnoop(Packet *pkt)
+Bus::timingSnoop(PacketPtr pkt, Port* responder)
{
std::vector<int> ports = findSnoopPorts(pkt->getAddr(), pkt->getSrc());
bool success = true;
while (!ports.empty() && success)
{
- success = interfaces[ports.back()]->sendTiming(pkt);
+ if (interfaces[ports.back()] != responder) //Don't call if responder also, once will do
+ success = interfaces[ports.back()]->sendTiming(pkt);
ports.pop_back();
}
/** Function called by the port when the bus is receiving a Atomic
* transaction.*/
Tick
-Bus::recvAtomic(Packet *pkt)
+Bus::recvAtomic(PacketPtr pkt)
{
DPRINTF(Bus, "recvAtomic: packet src %d dest %d addr 0x%x cmd %s\n",
pkt->getSrc(), pkt->getDest(), pkt->getAddr(), pkt->cmdString());
assert(pkt->getDest() == Packet::Broadcast);
- atomicSnoop(pkt);
- return findPort(pkt->getAddr(), pkt->getSrc())->sendAtomic(pkt);
+ pkt->flags |= SNOOP_COMMIT;
+
+ // Assume one bus cycle in order to get through. This may have
+ // some clock skew issues yet again...
+ pkt->finishTime = curTick + clock;
+
+ Port *port = findPort(pkt->getAddr(), pkt->getSrc());
+ Tick snoopTime = atomicSnoop(pkt, port ? port : interfaces[pkt->getSrc()]);
+
+ if (snoopTime)
+ return snoopTime; //Snoop satisfies it
+ else if (port)
+ return port->sendAtomic(pkt);
+ else
+ return 0;
}
/** Function called by the port when the bus is receiving a Functional
* transaction.*/
void
-Bus::recvFunctional(Packet *pkt)
+Bus::recvFunctional(PacketPtr pkt)
{
DPRINTF(Bus, "recvFunctional: packet src %d dest %d addr 0x%x cmd %s\n",
pkt->getSrc(), pkt->getDest(), pkt->getAddr(), pkt->cmdString());
assert(pkt->getDest() == Packet::Broadcast);
- functionalSnoop(pkt);
- findPort(pkt->getAddr(), pkt->getSrc())->sendFunctional(pkt);
+ pkt->flags |= SNOOP_COMMIT;
+
+ Port* port = findPort(pkt->getAddr(), pkt->getSrc());
+ functionalSnoop(pkt, port ? port : interfaces[pkt->getSrc()]);
+
+ // If the snooping found what we were looking for, we're done.
+ if (pkt->result != Packet::Success && port) {
+ port->sendFunctional(pkt);
+ }
}
/** Function called by the port when the bus is receiving a status change.*/
{
AddrRangeList ranges;
AddrRangeList snoops;
- int x;
AddrRangeIter iter;
assert(status == Port::RangeChange &&
if (id == defaultId) {
defaultRange.clear();
- defaultPort->getPeerAddressRanges(ranges, snoops);
- assert(snoops.size() == 0);
- for(iter = ranges.begin(); iter != ranges.end(); iter++) {
- defaultRange.push_back(*iter);
- DPRINTF(BusAddrRanges, "Adding range %#llx - %#llx for default range\n",
- iter->start, iter->end);
+ // Only try to update these ranges if the user set a default responder.
+ if (responderSet) {
+ defaultPort->getPeerAddressRanges(ranges, snoops);
+ assert(snoops.size() == 0);
+ for(iter = ranges.begin(); iter != ranges.end(); iter++) {
+ defaultRange.push_back(*iter);
+ DPRINTF(BusAddrRanges, "Adding range %#llx - %#llx for default range\n",
+ iter->start, iter->end);
+ }
}
} else {
- assert((id < interfaces.size() && id >= 0) || id == -1);
+ assert((id < maxId && id >= 0) || id == defaultId);
Port *port = interfaces[id];
- std::vector<DevMap>::iterator portIter;
+ range_map<Addr,int>::iterator portIter;
std::vector<DevMap>::iterator snoopIter;
// Clean out any previously existent ids
- for (portIter = portList.begin(); portIter != portList.end(); ) {
- if (portIter->portId == id)
- portIter = portList.erase(portIter);
+ for (portIter = portMap.begin(); portIter != portMap.end(); ) {
+ if (portIter->second == id)
+ portMap.erase(portIter++);
else
portIter++;
}
dm.portId = id;
dm.range = *iter;
+ //@todo, make sure we don't overlap ranges
DPRINTF(BusAddrRanges, "Adding snoop range %#llx - %#llx for id %d\n",
dm.range.start, dm.range.end, id);
portSnoopList.push_back(dm);
}
for(iter = ranges.begin(); iter != ranges.end(); iter++) {
- DevMap dm;
- dm.portId = id;
- dm.range = *iter;
-
DPRINTF(BusAddrRanges, "Adding range %#llx - %#llx for id %d\n",
- dm.range.start, dm.range.end, id);
- portList.push_back(dm);
+ iter->start, iter->end, id);
+ if (portMap.insert(*iter, id) == portMap.end())
+ panic("Two devices with same range\n");
+
}
}
- DPRINTF(MMU, "port list has %d entries\n", portList.size());
+ DPRINTF(MMU, "port list has %d entries\n", portMap.size());
// tell all our peers that our address range has changed.
// Don't tell the device that caused this change, it already knows
- for (x = 0; x < interfaces.size(); x++)
- if (x != id)
- interfaces[x]->sendStatusChange(Port::RangeChange);
+ m5::hash_map<short,BusPort*>::iterator intIter;
+
+ for (intIter = interfaces.begin(); intIter != interfaces.end(); intIter++)
+ if (intIter->first != id)
+ intIter->second->sendStatusChange(Port::RangeChange);
if (id != defaultId && defaultPort)
defaultPort->sendStatusChange(Port::RangeChange);
void
Bus::addressRanges(AddrRangeList &resp, AddrRangeList &snoop, int id)
{
- std::vector<DevMap>::iterator portIter;
+ std::vector<DevMap>::iterator snoopIter;
+ range_map<Addr,int>::iterator portIter;
AddrRangeIter dflt_iter;
bool subset;
for (dflt_iter = defaultRange.begin(); dflt_iter != defaultRange.end();
dflt_iter++) {
resp.push_back(*dflt_iter);
- DPRINTF(BusAddrRanges, " -- %#llx : %#llx\n",dflt_iter->start,
+ DPRINTF(BusAddrRanges, " -- Dflt: %#llx : %#llx\n",dflt_iter->start,
dflt_iter->end);
}
- for (portIter = portList.begin(); portIter != portList.end(); portIter++) {
+ for (portIter = portMap.begin(); portIter != portMap.end(); portIter++) {
subset = false;
for (dflt_iter = defaultRange.begin(); dflt_iter != defaultRange.end();
dflt_iter++) {
- if ((portIter->range.start < dflt_iter->start &&
- portIter->range.end >= dflt_iter->start) ||
- (portIter->range.start < dflt_iter->end &&
- portIter->range.end >= dflt_iter->end))
+ if ((portIter->first.start < dflt_iter->start &&
+ portIter->first.end >= dflt_iter->start) ||
+ (portIter->first.start < dflt_iter->end &&
+ portIter->first.end >= dflt_iter->end))
fatal("Devices can not set ranges that itersect the default set\
but are not a subset of the default set.\n");
- if (portIter->range.start >= dflt_iter->start &&
- portIter->range.end <= dflt_iter->end) {
+ if (portIter->first.start >= dflt_iter->start &&
+ portIter->first.end <= dflt_iter->end) {
subset = true;
DPRINTF(BusAddrRanges, " -- %#llx : %#llx is a SUBSET\n",
- portIter->range.start, portIter->range.end);
+ portIter->first.start, portIter->first.end);
}
}
- if (portIter->portId != id && !subset) {
- resp.push_back(portIter->range);
+ if (portIter->second != id && !subset) {
+ resp.push_back(portIter->first);
DPRINTF(BusAddrRanges, " -- %#llx : %#llx\n",
- portIter->range.start, portIter->range.end);
+ portIter->first.start, portIter->first.end);
}
}
+
+ for (snoopIter = portSnoopList.begin();
+ snoopIter != portSnoopList.end(); snoopIter++)
+ {
+ if (snoopIter->portId != id) {
+ snoop.push_back(snoopIter->range);
+ DPRINTF(BusAddrRanges, " -- Snoop: %#llx : %#llx\n",
+ snoopIter->range.start, snoopIter->range.end);
+ //@todo We need to properly insert snoop ranges
+ //not overlapping the ranges (multiple)
+ }
+ }
+}
+
+unsigned int
+Bus::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
+ //contacted for a retry didn't actually retry.
+ if (curTick >= tickNextIdle && retryList.size() == 0) {
+ return 0;
+ } else {
+ drainEvent = de;
+ return 1;
+ }
}
BEGIN_DECLARE_SIM_OBJECT_PARAMS(Bus)
Param<int> bus_id;
Param<int> clock;
Param<int> width;
+ Param<bool> responder_set;
END_DECLARE_SIM_OBJECT_PARAMS(Bus)
BEGIN_INIT_SIM_OBJECT_PARAMS(Bus)
INIT_PARAM(bus_id, "a globally unique bus id"),
INIT_PARAM(clock, "bus clock speed"),
- INIT_PARAM(width, "width of the bus (bits)")
+ INIT_PARAM(width, "width of the bus (bits)"),
+ INIT_PARAM(responder_set, "Is a default responder set by the user")
END_INIT_SIM_OBJECT_PARAMS(Bus)
CREATE_SIM_OBJECT(Bus)
{
- return new Bus(getInstanceName(), bus_id, clock, width);
+ return new Bus(getInstanceName(), bus_id, clock, width, responder_set);
}
REGISTER_SIM_OBJECT("Bus", Bus)