X86: Record the initial APIC ID which identifies an APIC in M5.

The ID as exposed to software can be changed. Tracking those changes in M5
would be cumbersome, especially since there's no guarantee the IDs will remain
unique.

src/arch/x86/interrupts.cc

@@ -295,17 +295,21 @@ X86ISA::Interrupts::requestInterrupt(uint8_t vector,
 void
 X86ISA::Interrupts::setCPU(BaseCPU * newCPU)
 {
+    assert(newCPU);
+    if (cpu != NULL && cpu->cpuId() != newCPU->cpuId()) {
+        panic("Local APICs can't be moved between CPUs"
+                " with different IDs.\n");
+    }
     cpu = newCPU;
-    assert(cpu);
+    initialApicId = cpu->cpuId();
-    regs[APIC_ID] = (cpu->cpuId() << 24);
+    regs[APIC_ID] = (initialApicId << 24);
 }
 
 
 Tick
 X86ISA::Interrupts::recvMessage(PacketPtr pkt)
 {
-    uint8_t id = (regs[APIC_ID] >> 24);
+    Addr offset = pkt->getAddr() - x86InterruptAddress(initialApicId, 0);
-    Addr offset = pkt->getAddr() - x86InterruptAddress(id, 0);
     assert(pkt->cmd == MemCmd::MessageReq);
     switch(offset)
     {
@@ -315,9 +319,6 @@ X86ISA::Interrupts::recvMessage(PacketPtr pkt)
             DPRINTF(LocalApic,
                     "Got Trigger Interrupt message with vector %#x.\n",
                     message.vector);
-            // Make sure we're really supposed to get this.
-            assert((message.destMode == 0 && message.destination == id) ||
-                   (bits((int)message.destination, id)));
 
             requestInterrupt(message.vector,
                     message.deliveryMode, message.trigger);
@@ -354,10 +355,10 @@ X86ISA::Interrupts::recvResponse(PacketPtr pkt)
 void
 X86ISA::Interrupts::addressRanges(AddrRangeList &range_list)
 {
-    uint8_t id = (regs[APIC_ID] >> 24);
     range_list.clear();
-    Range<Addr> range = RangeEx(x86LocalAPICAddress(id, 0),
+    Range<Addr> range = RangeEx(x86LocalAPICAddress(initialApicId, 0),
-                                x86LocalAPICAddress(id, 0) + PageBytes);
+                                x86LocalAPICAddress(initialApicId, 0) + 
+                                PageBytes);
     range_list.push_back(range);
     pioAddr = range.start;
 }
@@ -366,10 +367,10 @@ X86ISA::Interrupts::addressRanges(AddrRangeList &range_list)
 void
 X86ISA::Interrupts::getIntAddrRange(AddrRangeList &range_list)
 {
-    uint8_t id = (regs[APIC_ID] >> 24);
     range_list.clear();
-    range_list.push_back(RangeEx(x86InterruptAddress(id, 0),
+    range_list.push_back(RangeEx(x86InterruptAddress(initialApicId, 0),
-                x86InterruptAddress(id, 0) + PhysAddrAPICRangeSize));
+                x86InterruptAddress(initialApicId, 0) +
+                PhysAddrAPICRangeSize));
 }
 
 
@@ -515,14 +516,9 @@ X86ISA::Interrupts::setReg(ApicRegIndex reg, uint32_t val)
                 {
                     int numContexts = sys->numContexts();
                     pendingIPIs += (numContexts - 1);
-                    // We have no way to get at the thread context we're part
-                    // of, so we'll just have to go with the CPU for now.
-                    hack_once("Broadcast IPIs can't handle more than "
-                            "one context per CPU.\n");
-                    int myId = cpu->getContext(0)->contextId();
                     for (int i = 0; i < numContexts; i++) {
                         int thisId = sys->getThreadContext(i)->contextId();
-                        if (thisId != myId) {
+                        if (thisId != initialApicId) {
                             PacketPtr pkt = buildIntRequest(thisId, message);
                             if (timing)
                                 intPort->sendMessageTiming(pkt, latency);
@@ -589,7 +585,7 @@ X86ISA::Interrupts::Interrupts(Params * p) :
     pendingInit(false), initVector(0),
     pendingStartup(false), startupVector(0),
     startedUp(false), pendingUnmaskableInt(false),
-    pendingIPIs(0)
+    pendingIPIs(0), cpu(NULL)
 {
     pioSize = PageBytes;
     memset(regs, 0, sizeof(regs));

src/arch/x86/interrupts.hh

@@ -191,6 +191,8 @@ class Interrupts : public BasicPioDevice, IntDev
 
     BaseCPU *cpu;
 
+    int initialApicId;
+
   public:
     /*
      * Params stuff.

src/dev/x86/i82094aa.cc

@@ -40,7 +40,7 @@ X86ISA::I82094AA::I82094AA(Params *p) : PioDevice(p), IntDev(this),
     extIntPic(p->external_int_pic)
 {
     // This assumes there's only one I/O APIC in the system
-    id = p->apic_id;
+    initialApicId = id = p->apic_id;
     assert(id <= 0xf);
     arbId = id;
     regSel = 0;

src/dev/x86/i82094aa.hh

@@ -68,6 +68,7 @@ class I82094AA : public PioDevice, public IntDev
     I8259 * extIntPic;
 
     uint8_t regSel;
+    uint8_t initialApicId;
     uint8_t id;
     uint8_t arbId;
 
@@ -103,8 +104,9 @@ class I82094AA : public PioDevice, public IntDev
     void getIntAddrRange(AddrRangeList &range_list)
     {
         range_list.clear();
-        range_list.push_back(RangeEx(x86InterruptAddress(id, 0),
+        range_list.push_back(RangeEx(x86InterruptAddress(initialApicId, 0),
-                    x86InterruptAddress(id, 0) + PhysAddrAPICRangeSize));
+                    x86InterruptAddress(initialApicId, 0) +
+                    PhysAddrAPICRangeSize));
     }
 
     void writeReg(uint8_t offset, uint32_t value);