dev-arm: Do not panic in the SMMUv3 for fauting transactions

Rely on the architected solution instead of aborting simulation.
This means handling writes to the Event queue to signal managing
software there was a fault in the SMMU

Change-Id: I7b69ca77021732c6059bd6b837ae722da71350ff
Signed-off-by: Giacomo Travaglini <giacomo.travaglini@arm.com>

src/dev/arm/smmu_v3_transl.cc

@@ -229,13 +229,11 @@ SMMUTranslationProcess::main(Yield &yield)
         hazardIdHold(yield);
         hazardIdRelease();
 
-        if (tr.isFaulting())
-            panic("Translation Fault (addr=%#x, size=%#x, sid=%d, ssid=%d, "
-                    "isWrite=%d, isPrefetch=%d, isAtsRequest=%d)\n",
-                    request.addr, request.size, request.sid, request.ssid,
-                    request.isWrite, request.isPrefetch, request.isAtsRequest);
-
-        completeTransaction(yield, tr);
+        if (tr.isFaulting()) {
+            abortTransaction(yield, tr);
+        } else {
+            completeTransaction(yield, tr);
+        }
     }
 }
 
@@ -1232,6 +1230,46 @@ SMMUTranslationProcess::issuePrefetch(Addr addr)
     proc->scheduleWakeup(smmu.clockEdge(Cycles(1)));
 }
 
+void
+SMMUTranslationProcess::abortTransaction(Yield &yield,
+                                         const TranslResult &tr)
+{
+    DPRINTF(SMMUv3, "Translation Fault (addr=%#x, size=%#x, sid=%d, ssid=%d, "
+            "isWrite=%d, isPrefetch=%d, isAtsRequest=%d)\n",
+            request.addr, request.size, request.sid, request.ssid,
+            request.isWrite, request.isPrefetch, request.isAtsRequest);
+
+    // If eventq is not enabled, silently discard event
+    // TODO: Handle full queue (we are currently aborting
+    // in send event)
+    if (smmu.regs.cr0 & CR0_EVENTQEN_MASK) {
+        SMMUEvent event = generateEvent(tr);
+
+        sendEvent(yield, event);
+    }
+
+    ifc.xlateSlotsRemaining++;
+    smmu.scheduleDeviceRetries();
+
+    if (smmu.system.isAtomicMode()) {
+        request.pkt->makeAtomicResponse();
+    } else if (smmu.system.isTimingMode()) {
+        request.pkt->makeTimingResponse();
+    } else {
+        panic("Not in atomic or timing mode");
+    }
+
+    request.pkt->setBadAddress();
+
+    SMMUAction a;
+    // Send the bad address response to the client device
+    a.type = ACTION_SEND_RESP;
+    a.pkt = request.pkt;
+    a.ifc = &ifc;
+    a.delay = 0;
+    yield(a);
+}
+
 void
 SMMUTranslationProcess::completeTransaction(Yield &yield,
                                             const TranslResult &tr)

src/dev/arm/smmu_v3_transl.hh

@@ -220,6 +220,7 @@ class SMMUTranslationProcess : public SMMUProcess
 
     void issuePrefetch(Addr addr);
 
+    void abortTransaction(Yield &yield, const TranslResult &tr);
     void completeTransaction(Yield &yield, const TranslResult &tr);
     void completePrefetch(Yield &yield);