dev: Generalize the x86 int source/sink pins.

Sink pins are now templated based on the underlying device types, and
the pins themselves are based on the new, generalized Port mechanism.

Change-Id: I09c678c56f6eb6b4a167c12f221ae0241fe99c2d
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/20700
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>

4 files changed, 244 insertions, 0 deletions

diff --git a/src/dev/IntPin.py b/src/dev/IntPin.py
new file mode 100644
index 000000000..8fe3b2363
--- /dev/null
+++ b/src/dev/IntPin.py
@@ -0,0 +1,52 @@
+# Copyright 2019 Google, Inc.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met: redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer;
+# redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution;
+# neither the name of the copyright holders nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#
+# Authors: Gabe Black
+
+from m5.params import Port, VectorPort
+
+INT_SOURCE_ROLE = 'Int Source Pin'
+INT_SINK_ROLE = 'Int Sink Pin'
+Port.compat(INT_SOURCE_ROLE, INT_SINK_ROLE)
+
+# A source pin generally represents a single pin which might connect to
+# multiple sinks.
+class IntSourcePin(VectorPort):
+    def __init__(self, desc):
+        super(IntSourcePin, self).__init__(
+                INT_SOURCE_ROLE, desc, is_source=True)
+
+# Each "physical" pin can be driven by a single source pin since there are no
+# provisions for resolving competing signals running to the same pin.
+class IntSinkPin(Port):
+    def __init__(self, desc):
+        super(IntSinkPin, self).__init__(INT_SINK_ROLE, desc)
+
+# A vector of sink pins represents a bank of physical pins. For instance, an
+# interrupt controller with many numbered input interrupts could represent them
+# as a VectorIntSinkPin.
+class VectorIntSinkPin(VectorPort):
+    def __init__(self, desc):
+        super(VectorIntSinkPin, self).__init__(INT_SINK_ROLE, desc)
diff --git a/src/dev/SConscript b/src/dev/SConscript
index ecb6dccbb..69c30a693 100644
--- a/src/dev/SConscript
+++ b/src/dev/SConscript
@@ -36,6 +36,9 @@ Source('io_device.cc')
 Source('isa_fake.cc')
 Source('dma_device.cc')
 
+SimObject('IntPin.py')
+Source('intpin.cc')
+
 DebugFlag('IsaFake')
 DebugFlag('DMA')
 
diff --git a/src/dev/intpin.cc b/src/dev/intpin.cc
new file mode 100644
index 000000000..dfb03aa8d
--- /dev/null
+++ b/src/dev/intpin.cc
@@ -0,0 +1,69 @@
+/*
+ * Copyright 2019 Google, Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met: redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer;
+ * redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution;
+ * neither the name of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Authors: Gabe Black
+ */
+
+#include "dev/intpin.hh"
+
+#include "base/logging.hh"
+
+void
+IntSinkPinBase::bind(Port &peer)
+{
+    source = dynamic_cast<IntSourcePinBase *>(&peer);
+    fatal_if(!source, "Attempt to bind interrupt sink pin %s to "
+            "incompatible port %s.", name(), peer.name());
+    Port::bind(peer);
+}
+
+void
+IntSinkPinBase::unbind()
+{
+    source = nullptr;
+    Port::unbind();
+}
+
+void
+IntSourcePinBase::bind(Port &peer)
+{
+    sink = dynamic_cast<IntSinkPinBase *>(&peer);
+    fatal_if(!sink, "Attempt to bind interrupt source pin %s to "
+            "incompatible port %s.", name(), peer.name());
+    Port::bind(peer);
+
+    if (_state)
+        raise();
+    else
+        lower();
+}
+
+void
+IntSourcePinBase::unbind()
+{
+    sink = nullptr;
+    Port::unbind();
+}
diff --git a/src/dev/intpin.hh b/src/dev/intpin.hh
new file mode 100644
index 000000000..e00aa625d
--- /dev/null
+++ b/src/dev/intpin.hh
@@ -0,0 +1,120 @@
+/*
+ * Copyright 2019 Google, Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met: redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer;
+ * redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution;
+ * neither the name of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Authors: Gabe Black
+ */
+
+#ifndef __DEV_INTPIN_HH__
+#define __DEV_INTPIN_HH__
+
+#include "sim/port.hh"
+
+class IntSourcePinBase;
+
+class IntSinkPinBase : public Port
+{
+  protected:
+    friend IntSourcePinBase;
+
+    IntSourcePinBase *source = nullptr;
+
+    int _number = 0;
+    bool _state = false;
+
+    IntSinkPinBase(const std::string &_name, PortID _id, int num) :
+        Port(_name, _id), _number(num)
+    {}
+
+    virtual void raiseOnDevice() = 0;
+    virtual void lowerOnDevice() = 0;
+
+    void
+    raise()
+    {
+        _state = true;
+        raiseOnDevice();
+    }
+
+    void
+    lower()
+    {
+        _state = false;
+        lowerOnDevice();
+    }
+
+  public:
+    int number() { return _number; }
+    bool state() { return _state; }
+
+    void bind(Port &peer) override;
+    void unbind() override;
+};
+
+template <class Device>
+class IntSinkPin : public IntSinkPinBase
+{
+  private:
+    Device *device = nullptr;
+
+    void raiseOnDevice() override { device->raiseInterruptPin(number()); }
+    void lowerOnDevice() override { device->lowerInterruptPin(number()); }
+
+  public:
+    IntSinkPin(const std::string &_name, PortID _id, Device *dev, int num) :
+        IntSinkPinBase(_name, _id, num), device(dev) {}
+    IntSinkPin(const std::string &_name, PortID _id, Device *dev) :
+        IntSinkPin(_name, _id, dev, _id) {}
+};
+
+class IntSourcePinBase : public Port
+{
+  private:
+    IntSinkPinBase *sink = nullptr;
+    bool _state = false;
+
+  public:
+    IntSourcePinBase(const std::string &_name, PortID _id, bool def_state) :
+        Port(_name, _id), _state(def_state)
+    {}
+
+    void raise() { sink->raise(); }
+    void lower() { sink->lower(); }
+
+    void bind(Port &peer) override;
+    void unbind() override;
+};
+
+template <class Device>
+class IntSourcePin : public IntSourcePinBase
+{
+  public:
+    IntSourcePin(const std::string &_name, PortID _id, Device *owner,
+                 bool def_state=false) :
+        IntSourcePinBase(_name, _id, def_state)
+    {}
+};
+
+#endif //__DEV_INTPIN_HH__