mem: Fix guest corruption when caches handle uncacheable accesses

[gem5.git] / src / mem / coherent_bus.cc

diff --git a/src/mem/coherent_bus.cc b/src/mem/coherent_bus.cc
index f7d4b9d11b1c302ebc52b16ec26fd05288594cd2..b1ac6dbcf01f79511753d7630adacc7a41e50acf 100644 (file)
--- a/src/mem/coherent_bus.cc
+++ b/src/mem/coherent_bus.cc
@@ -54,13 +54,15 @@
 #include "mem/coherent_bus.hh"
 
 CoherentBus::CoherentBus(const CoherentBusParams *p)
-    : BaseBus(p)
+    : BaseBus(p), reqLayer(*this, ".reqLayer", p->clock),
+      respLayer(*this, ".respLayer", p->clock),
+      snoopRespLayer(*this, ".snoopRespLayer", p->clock)
 {
     // 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);
+        std::string portName = csprintf("%s.master[%d]", name(), i);
         MasterPort* bp = new CoherentBusMasterPort(portName, *this, i);
         masterPorts.push_back(bp);
     }
@@ -69,7 +71,7 @@ CoherentBus::CoherentBus(const CoherentBusParams *p)
     // our corresponding master port
     if (p->port_default_connection_count) {
         defaultPortID = masterPorts.size();
-        std::string portName = csprintf("%s-default", name());
+        std::string portName = name() + ".default";
         MasterPort* bp = new CoherentBusMasterPort(portName, *this,
                                                    defaultPortID);
         masterPorts.push_back(bp);
@@ -77,7 +79,7 @@ CoherentBus::CoherentBus(const CoherentBusParams *p)
 
     // 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);
+        std::string portName = csprintf("%s.slave[%d]", name(), i);
         SlavePort* bp = new CoherentBusSlavePort(portName, *this, i);
         slavePorts.push_back(bp);
     }
@@ -88,6 +90,9 @@ CoherentBus::CoherentBus(const CoherentBusParams *p)
 void
 CoherentBus::init()
 {
+    // the base class is responsible for determining the block size
+    BaseBus::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();
@@ -115,7 +120,7 @@ CoherentBus::recvTimingReq(PacketPtr pkt, PortID slave_port_id)
 
     // test if the bus should be considered occupied for the current
     // port, and exclude express snoops from the check
-    if (!is_express_snoop && !tryTiming(src_port)) {
+    if (!is_express_snoop && !reqLayer.tryTiming(src_port)) {
         DPRINTF(CoherentBus, "recvTimingReq: src %s %s 0x%x BUSY\n",
                 src_port->name(), pkt->cmdString(), pkt->getAddr());
         return false;
@@ -176,10 +181,10 @@ CoherentBus::recvTimingReq(PacketPtr pkt, PortID slave_port_id)
                     src_port->name(), pkt->cmdString(), pkt->getAddr());
 
             // update the bus state and schedule an idle event
-            failedTiming(src_port, headerFinishTime);
+            reqLayer.failedTiming(src_port, headerFinishTime);
         } else {
             // update the bus state and schedule an idle event
-            succeededTiming(packetFinishTime);
+            reqLayer.succeededTiming(packetFinishTime);
         }
     }
 
@@ -194,7 +199,7 @@ CoherentBus::recvTimingResp(PacketPtr pkt, PortID master_port_id)
 
     // test if the bus should be considered occupied for the current
     // port
-    if (!tryTiming(src_port)) {
+    if (!respLayer.tryTiming(src_port)) {
         DPRINTF(CoherentBus, "recvTimingResp: src %s %s 0x%x BUSY\n",
                 src_port->name(), pkt->cmdString(), pkt->getAddr());
         return false;
@@ -221,7 +226,7 @@ CoherentBus::recvTimingResp(PacketPtr pkt, PortID master_port_id)
     // deadlock
     assert(success);
 
-    succeededTiming(packetFinishTime);
+    respLayer.succeededTiming(packetFinishTime);
 
     return true;
 }
@@ -258,7 +263,7 @@ CoherentBus::recvTimingSnoopResp(PacketPtr pkt, PortID slave_port_id)
 
     // test if the bus should be considered occupied for the current
     // port
-    if (!tryTiming(src_port)) {
+    if (!snoopRespLayer.tryTiming(src_port)) {
         DPRINTF(CoherentBus, "recvTimingSnoopResp: src %s %s 0x%x BUSY\n",
                 src_port->name(), pkt->cmdString(), pkt->getAddr());
         return false;
@@ -309,7 +314,7 @@ CoherentBus::recvTimingSnoopResp(PacketPtr pkt, PortID slave_port_id)
         assert(success);
     }
 
-    succeededTiming(packetFinishTime);
+    snoopRespLayer.succeededTiming(packetFinishTime);
 
     return true;
 }
@@ -332,6 +337,15 @@ CoherentBus::forwardTiming(PacketPtr pkt, PortID exclude_slave_port_id)
     }
 }
 
+void
+CoherentBus::recvRetry()
+{
+    // responses and snoop responses never block on forwarding them,
+    // so the retry will always be coming from a port to which we
+    // tried to forward a request
+    reqLayer.recvRetry();
+}
+
 Tick
 CoherentBus::recvAtomic(PacketPtr pkt, PortID slave_port_id)
 {
@@ -493,6 +507,13 @@ CoherentBus::forwardFunctional(PacketPtr pkt, PortID exclude_slave_port_id)
     }
 }
 
+unsigned int
+CoherentBus::drain(DrainManager *dm)
+{
+    // sum up the individual layers
+    return reqLayer.drain(dm) + respLayer.drain(dm) + snoopRespLayer.drain(dm);
+}
+
 CoherentBus *
 CoherentBusParams::create()
 {