systemc: Add a stub kernel SimObject.

The guts of this class will be added in later changes.

Change-Id: I3582c40f88f7d9ba6028a6f0a8ee5c32924a65bf
Reviewed-on: https://gem5-review.googlesource.com/10822
Maintainer: Gabe Black <gabeblack@google.com>
Reviewed-by: Giacomo Travaglini <giacomo.travaglini@arm.com>

src/systemc/SConscript

@@ -30,4 +30,6 @@ Import('*')
 if env['USE_SYSTEMC']:
     SimObject('SystemC.py')
 
+    Source('kernel.cc')
+
     Source('sc_object.cc')

src/systemc/SystemC.py

@@ -27,6 +27,15 @@
 
 from m5.SimObject import SimObject
 
+# This class represents the systemc kernel. There should be exactly one in the
+# simulation. It receives gem5 SimObject lifecycle callbacks (init, regStats,
+# etc.) and manages the lifecycle of the systemc simulation accordingly.
+# It also acts as a collecting point for systemc related control functionality.
+class SystemC_Kernel(SimObject):
+    type = 'SystemC_Kernel'
+    cxx_class = 'SystemC::Kernel'
+    cxx_header = 'systemc/kernel.hh'
+
 # This class represents systemc sc_object instances in python config files. It
 # inherits from SimObject in python, but the c++ version, sc_core::sc_object,
 # doesn't inherit from gem5's c++ SimObject class.

src/systemc/kernel.cc

@@ -0,0 +1,45 @@
+/*
+ * Copyright 2018 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 "systemc/kernel.hh"
+
+namespace SystemC
+{
+
+Kernel::Kernel(Params *params) : SimObject(params)
+{
+}
+
+} // namespace SystemC
+
+SystemC::Kernel *
+SystemC_KernelParams::create()
+{
+    return new SystemC::Kernel(this);
+}

src/systemc/kernel.hh

@@ -0,0 +1,55 @@
+/*
+ * Copyright 2018 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 __SYSTEMC_KERNEL_HH__
+#define __SYSTEMC_KERNEL_HH__
+
+#include "params/SystemC_Kernel.hh"
+#include "sim/sim_object.hh"
+
+namespace SystemC
+{
+
+/*
+ * This class represents the systemc kernel. There should be exactly one in
+ * the simulation. It receives gem5 SimObject lifecycle callbacks (init,
+ * regStats, etc.) and manages the lifecycle of the systemc simulation
+ * accordingly. It also acts as a collecting point for systemc related
+ * control functionality.
+ */
+class Kernel : public SimObject
+{
+  public:
+    typedef SystemC_KernelParams Params;
+    Kernel(Params *params);
+};
+
+} // namespace SystemC
+
+#endif // __SYSTEMC_KERNEL_H__