X86: Rework interrupt pins to allow one to many connections.

src/dev/x86/Cmos.py

@@ -29,6 +29,7 @@
 from m5.params import *
 from m5.proxy import *
 from Device import BasicPioDevice
+from X86IntPin import X86IntSourcePin
 
 class Cmos(BasicPioDevice):
     type = 'Cmos'
@@ -36,4 +37,5 @@ class Cmos(BasicPioDevice):
     time = Param.Time('01/01/2009',
         "System time to use ('Now' for actual time)")
     pio_latency = Param.Latency('1ns', "Programmed IO latency in simticks")
-    int_pin = Param.X86IntPin('Pin to signal RTC alarm interrupts to')
+    int_pin = Param.X86IntSourcePin(X86IntSourcePin(),
+            'Pin to signal RTC alarm interrupts to')

src/dev/x86/I82094AA.py

@@ -29,7 +29,7 @@
 from m5.params import *
 from m5.proxy import *
 from Device import BasicPioDevice
-from X86IntPin import X86IntPin
+from X86IntPin import X86IntSinkPin
 
 class I82094AA(BasicPioDevice):
     type = 'I82094AA'
@@ -37,6 +37,7 @@ class I82094AA(BasicPioDevice):
     pio_latency = Param.Latency('1ns', "Programmed IO latency in simticks")
     pio_addr = Param.Addr("Device address")
     int_port = Port("Port for sending and receiving interrupt messages")
+    external_int_pic = Param.I8259("External PIC, if any")
 
     def pin(self, line):
-        return X86IntPin(device=self, line=line)
+        return X86IntSinkPin(device=self, number=line)

src/dev/x86/I8254.py

@@ -29,9 +29,11 @@
 from m5.params import *
 from m5.proxy import *
 from Device import BasicPioDevice
+from X86IntPin import X86IntSourcePin
 
 class I8254(BasicPioDevice):
     type = 'I8254'
     cxx_class = 'X86ISA::I8254'
     pio_latency = Param.Latency('1ns', "Programmed IO latency in simticks")
-    int_pin = Param.X86IntPin('Pin to signal timer interrupts to')
+    int_pin = Param.X86IntSourcePin(X86IntSourcePin(),
+            'Pin to signal timer interrupts to')

src/dev/x86/I8259.py

@@ -29,7 +29,7 @@
 from m5.params import *
 from m5.proxy import *
 from Device import BasicPioDevice
-from X86IntPin import X86IntPin
+from X86IntPin import X86IntSourcePin, X86IntSinkPin
 
 class X86I8259CascadeMode(Enum):
     map = {'I8259Master' : 0,
@@ -41,8 +41,10 @@ class I8259(BasicPioDevice):
     type = 'I8259'
     cxx_class='X86ISA::I8259'
     pio_latency = Param.Latency('1ns', "Programmed IO latency in simticks")
-    output = Param.X86IntPin('The pin this I8259 drives')
+    output = Param.X86IntSourcePin(X86IntSourcePin(),
+            'The pin this I8259 drives')
     mode = Param.X86I8259CascadeMode('How this I8259 is cascaded')
+    slave = Param.I8259('Slave I8259, if any')
 
     def pin(self, line):
-        return X86IntPin(device=self, line=line)
+        return X86IntSinkPin(device=self, number=line)

src/dev/x86/SouthBridge.py

@@ -34,6 +34,7 @@ from I8237 import I8237
 from I8254 import I8254
 from I8259 import I8259
 from PcSpeaker import PcSpeaker
+from X86IntPin import X86IntLine
 from m5.SimObject import SimObject
 
 def x86IOAddress(port):
@@ -52,6 +53,9 @@ class SouthBridge(SimObject):
     _pit = I8254(pio_addr=x86IOAddress(0x40))
     _speaker = PcSpeaker(pio_addr=x86IOAddress(0x61))
     _io_apic = I82094AA(pio_addr=0xFEC00000)
+    # This is to make sure the interrupt lines are instantiated. Don't use
+    # it for anything directly.
+    int_lines = VectorParam.X86IntLine([], "Interrupt lines")
 
     pic1 = Param.I8259(_pic1, "Master PIC")
     pic2 = Param.I8259(_pic2, "Slave PIC")
@@ -61,13 +65,20 @@ class SouthBridge(SimObject):
     speaker = Param.PcSpeaker(_speaker, "PC speaker")
     io_apic = Param.I82094AA(_io_apic, "I/O APIC")
 
+    def connectPins(self, source, sink):
+        self.int_lines.append(X86IntLine(source=source, sink=sink))
+
     def attachIO(self, bus):
-        # Make internal connections
-        self.pic1.output = self.io_apic.pin(0)
-        self.pic2.output = self.pic1.pin(2)
-        self.cmos.int_pin = self.pic2.pin(0)
-        self.pit.int_pin = self.pic1.pin(0)
+        # Route interupt signals
+        self.connectPins(self.pic1.output, self.io_apic.pin(0))
+        self.connectPins(self.pic2.output, self.pic1.pin(2))
+        self.connectPins(self.cmos.int_pin, self.pic2.pin(0))
+        self.connectPins(self.pit.int_pin, self.pic1.pin(0))
+        self.connectPins(self.pit.int_pin, self.io_apic.pin(2))
+        # Tell the devices about each other
+        self.pic1.slave = self.pic2
         self.speaker.i8254 = self.pit
+        self.io_apic.external_int_pic = self.pic1
         # Connect to the bus
         self.cmos.pio = bus.port
         self.dma1.pio = bus.port

src/dev/x86/X86IntPin.py

@@ -29,9 +29,23 @@
 from m5.params import *
 from m5.SimObject import SimObject
 
-class X86IntPin(SimObject):
-    type = 'X86IntPin'
-    cxx_class = 'X86ISA::IntPin'
+# A generic pin to drive an interrupt signal generated by a device.
+class X86IntSourcePin(SimObject):
+    type = 'X86IntSourcePin'
+    cxx_class = 'X86ISA::IntSourcePin'
 
-    line = Param.Int("Interrupt line for this pin")
-    device = Param.SimObject("Device which handles interrupts")
+# A generic pin to receive an interrupt signal generated by another device.
+class X86IntSinkPin(SimObject):
+    type = 'X86IntSinkPin'
+    cxx_class = 'X86ISA::IntSinkPin'
+
+    device = Param.SimObject("Device this pin belongs to")
+    number = Param.Int("The pin number on the device")
+
+# An interrupt line which is driven by a source pin and drives a sink pin.
+class X86IntLine(SimObject):
+    type = 'X86IntLine'
+    cxx_class = 'X86ISA::IntLine'
+
+    source = Param.X86IntSourcePin("Pin driving this line")
+    sink = Param.X86IntSinkPin("Pin driven by this line")

src/dev/x86/cmos.cc

@@ -36,7 +36,9 @@ void
 X86ISA::Cmos::X86RTC::handleEvent()
 {
     assert(intPin);
-    intPin->signalInterrupt();
+    intPin->raise();
+    //XXX This is a hack.
+    intPin->lower();
 }
 
 Tick

src/dev/x86/cmos.hh

@@ -38,7 +38,7 @@
 namespace X86ISA
 {
 
-class IntPin;
+class IntSourcePin;
 
 class Cmos : public BasicPioDevice
 {
@@ -57,10 +57,10 @@ class Cmos : public BasicPioDevice
     class X86RTC : public MC146818
     {
       protected:
-        IntPin * intPin;
+        IntSourcePin * intPin;
       public:
         X86RTC(EventManager *em, const std::string &n, const struct tm time,
-                bool bcd, Tick frequency, IntPin * _intPin) :
+                bool bcd, Tick frequency, IntSourcePin * _intPin) :
             MC146818(em, n, time, bcd, frequency), intPin(_intPin)
         {
         }

src/dev/x86/i82094aa.cc

@@ -36,7 +36,8 @@
 #include "sim/system.hh"
 
 X86ISA::I82094AA::I82094AA(Params *p) : PioDevice(p), IntDev(this),
-   latency(p->pio_latency), pioAddr(p->pio_addr), extIntPic(NULL)
+    latency(p->pio_latency), pioAddr(p->pio_addr),
+    extIntPic(p->external_int_pic)
 {
     // This assumes there's only one I/O APIC in the system
     id = sys->numContexts();
@@ -47,6 +48,7 @@ X86ISA::I82094AA::I82094AA(Params *p) : PioDevice(p), IntDev(this),
     entry.mask = 1;
     for (int i = 0; i < TableSize; i++) {
         redirTable[i] = entry;
+        pinStates[i] = false;
     }
 }
 
@@ -209,6 +211,22 @@ X86ISA::I82094AA::signalInterrupt(int line)
     }
 }
 
+void
+X86ISA::I82094AA::raiseInterruptPin(int number)
+{
+    assert(number < TableSize);
+    if (!pinStates[number])
+        signalInterrupt(number);
+    pinStates[number] = true;
+}
+
+void
+X86ISA::I82094AA::lowerInterruptPin(int number)
+{
+    assert(number < TableSize);
+    pinStates[number] = false;
+}
+
 X86ISA::I82094AA *
 I82094AAParams::create()
 {

src/dev/x86/i82094aa.hh

@@ -77,6 +77,7 @@ class I82094AA : public PioDevice, public IntDev
     static const uint8_t APICVersion = 0x14;
 
     RedirTableEntry redirTable[TableSize];
+    bool pinStates[TableSize];
 
   public:
     typedef I82094AAParams Params;
@@ -89,12 +90,6 @@ class I82094AA : public PioDevice, public IntDev
 
     I82094AA(Params *p);
 
-    void
-    setExtIntPic(I8259 * pic)
-    {
-        extIntPic = pic;
-    }
-
     Tick read(PacketPtr pkt);
     Tick write(PacketPtr pkt);
 
@@ -123,6 +118,8 @@ class I82094AA : public PioDevice, public IntDev
     }
 
     void signalInterrupt(int line);
+    void raiseInterruptPin(int number);
+    void lowerInterruptPin(int number);
 };
 
 }; // namespace X86ISA

src/dev/x86/i8254.cc

@@ -37,8 +37,11 @@ void
 X86ISA::I8254::counterInterrupt(unsigned int num)
 {
     DPRINTF(I8254, "Interrupt from counter %d.\n", num);
-    if (num == 0)
-        intPin->signalInterrupt();
+    if (num == 0) {
+        intPin->raise();
+        //XXX This is a hack.
+        intPin->lower();
+    }
 }
 
 Tick

src/dev/x86/i8254.hh

@@ -38,7 +38,7 @@
 namespace X86ISA
 {
 
-class IntPin;
+class IntSourcePin;
 
 class I8254 : public BasicPioDevice
 {
@@ -64,7 +64,7 @@ class I8254 : public BasicPioDevice
     
     X86Intel8254Timer pit;
 
-    IntPin *intPin;
+    IntSourcePin *intPin;
     
     void counterInterrupt(unsigned int num);
 

src/dev/x86/i8259.cc

@@ -36,20 +36,12 @@
 
 X86ISA::I8259::I8259(Params * p) : BasicPioDevice(p), IntDev(this),
                     latency(p->pio_latency), output(p->output),
-                    mode(p->mode), slave(NULL),
+                    mode(p->mode), slave(p->slave),
                     IRR(0), ISR(0), IMR(0),
                     readIRR(true), initControlWord(0), autoEOI(false)
 {
-    if (output) {
-        I8259 * master;
-        master = dynamic_cast<I8259 *>(output->getDevice());
-        if (master)
-            master->setSlave(this);
-        I82094AA * ioApic;
-        ioApic = dynamic_cast<I82094AA *>(output->getDevice());
-        if (ioApic)
-            ioApic->setExtIntPic(this);
-    }
+    for (int i = 0; i < NumLines; i++)
+        pinStates[i] = false;
     pioSize = 2;
 }
 
@@ -237,7 +229,9 @@ X86ISA::I8259::requestInterrupt(int line)
     if (bits(ISR, 7, line) == 0) {
         if (output) {
             DPRINTF(I8259, "Propogating interrupt.\n");
-            output->signalInterrupt();
+            output->raise();
+            //XXX This is a hack.
+            output->lower();
         } else {
             warn("Received interrupt but didn't have "
                     "anyone to tell about it.\n");
@@ -260,6 +254,26 @@ X86ISA::I8259::signalInterrupt(int line)
     }
 }
 
+void
+X86ISA::I8259::raiseInterruptPin(int number)
+{
+    if (number >= NumLines)
+        fatal("Line number %d doesn't exist. The max is %d.\n",
+                number, NumLines - 1);
+    if (!pinStates[number])
+        signalInterrupt(number);
+    pinStates[number] = true;
+}
+
+void
+X86ISA::I8259::lowerInterruptPin(int number)
+{
+    if (number >= NumLines)
+        fatal("Line number %d doesn't exist. The max is %d.\n",
+                number, NumLines - 1);
+    pinStates[number] = false;
+}
+
 int
 X86ISA::I8259::getVector()
 {

src/dev/x86/i8259.hh

@@ -45,9 +45,10 @@ class I8259 : public BasicPioDevice, public IntDev
 {
   protected:
     static const int NumLines = 8;
+    bool pinStates[NumLines];
 
     Tick latency;
-    IntPin *output;
+    IntSourcePin *output;
     Enums::X86I8259CascadeMode mode;
     I8259 * slave;
 
@@ -90,16 +91,12 @@ class I8259 : public BasicPioDevice, public IntDev
 
     I8259(Params * p);
 
-    void
-    setSlave(I8259 * _slave)
-    {
-        slave = _slave;
-    }
-
     Tick read(PacketPtr pkt);
     Tick write(PacketPtr pkt);
 
     void signalInterrupt(int line);
+    void raiseInterruptPin(int number);
+    void lowerInterruptPin(int number);
     int getVector();
 };
 

src/dev/x86/intdev.cc

@@ -30,8 +30,20 @@
 
 #include "dev/x86/intdev.hh"
 
-X86ISA::IntPin *
-X86IntPinParams::create()
+X86ISA::IntSourcePin *
+X86IntSourcePinParams::create()
 {
-    return new X86ISA::IntPin(this);
+    return new X86ISA::IntSourcePin(this);
+}
+
+X86ISA::IntSinkPin *
+X86IntSinkPinParams::create()
+{
+    return new X86ISA::IntSinkPin(this);
+}
+
+X86ISA::IntLine *
+X86IntLineParams::create()
+{
+    return new X86ISA::IntLine(this);
 }

src/dev/x86/intdev.hh

@@ -38,7 +38,9 @@
 #include "mem/mem_object.hh"
 #include "mem/mport.hh"
 #include "sim/sim_object.hh"
-#include "params/X86IntPin.hh"
+#include "params/X86IntSourcePin.hh"
+#include "params/X86IntSinkPin.hh"
+#include "params/X86IntLine.hh"
 
 namespace X86ISA {
 
@@ -99,6 +101,18 @@ class IntDev
         panic("signalInterrupt not implemented.\n");
     }
 
+    virtual void
+    raiseInterruptPin(int number)
+    {
+        panic("raiseInterruptPin not implemented.\n");
+    }
+
+    virtual void
+    lowerInterruptPin(int number)
+    {
+        panic("lowerInterruptPin not implemented.\n");
+    }
+
     virtual Tick
     recvMessage(PacketPtr pkt)
     {
@@ -113,20 +127,13 @@ class IntDev
     }
 };
 
-class IntPin : public SimObject
+class IntSinkPin : public SimObject
 {
-  protected:
-    IntDev * device;
-    int line;
-
   public:
-    typedef X86IntPinParams Params;
+    IntDev * device;
+    int number;
 
-    IntDev *
-    getDevice() const
-    {
-        return device;
-    }
+    typedef X86IntSinkPinParams Params;
 
     const Params *
     params() const
@@ -134,16 +141,73 @@ class IntPin : public SimObject
         return dynamic_cast<const Params *>(_params);
     }
 
-    IntPin(Params *p) : SimObject(p),
-            device(dynamic_cast<IntDev *>(p->device)), line(p->line)
+    IntSinkPin(Params *p) : SimObject(p),
+            device(dynamic_cast<IntDev *>(p->device)), number(p->number)
     {
         assert(device);
     }
+};
+
+class IntSourcePin : public SimObject
+{
+  protected:
+    std::vector<IntSinkPin *> sinks;
+
+  public:
+    typedef X86IntSourcePinParams Params;
+
+    const Params *
+    params() const
+    {
+        return dynamic_cast<const Params *>(_params);
+    }
 
     void
-    signalInterrupt()
+    addSink(IntSinkPin *sink)
     {
-        device->signalInterrupt(line);
+        sinks.push_back(sink);
+    }
+
+    void
+    raise()
+    {
+        for (int i = 0; i < sinks.size(); i++) {
+            const IntSinkPin &pin = *sinks[i];
+            pin.device->raiseInterruptPin(pin.number);
+        }
+    }
+    
+    void
+    lower()
+    {
+        for (int i = 0; i < sinks.size(); i++) {
+            const IntSinkPin &pin = *sinks[i];
+            pin.device->lowerInterruptPin(pin.number);
+        }
+    }
+
+    IntSourcePin(Params *p) : SimObject(p)
+    {}
+};
+
+class IntLine : public SimObject
+{
+  protected:
+    IntSourcePin *source;
+    IntSinkPin *sink;
+
+  public:
+    typedef X86IntLineParams Params;
+
+    const Params *
+    params() const
+    {
+        return dynamic_cast<const Params *>(_params);
+    }
+
+    IntLine(Params *p) : SimObject(p), source(p->source), sink(p->sink)
+    {
+        source->addSink(sink);
     }
 };