ext: add the source code for DSENT

This patch adds a tool called DSENT to the ext/ directory.  DSENT
is a tool that models power and area for on-chip networks.  The next
patch adds a script for using the tool.

1 files changed, 53 insertions, 0 deletions

diff --git a/ext/dsent/model/timing_graph/ElectricalDriverMultiplier.cc b/ext/dsent/model/timing_graph/ElectricalDriverMultiplier.cc
new file mode 100644
index 000000000..bf8600fd8
--- /dev/null
+++ b/ext/dsent/model/timing_graph/ElectricalDriverMultiplier.cc
@@ -0,0 +1,53 @@
+
+#include "model/timing_graph/ElectricalDriverMultiplier.h"
+#include "model/timing_graph/ElectricalLoad.h"
+
+namespace DSENT
+{
+    //-------------------------------------------------------------------------
+    // Electrical Net
+    //-------------------------------------------------------------------------
+
+    ElectricalDriverMultiplier::ElectricalDriverMultiplier(const String& instance_name_, ElectricalModel* model_)
+        : ElectricalTimingNode(instance_name_, model_)
+    {
+
+    }
+
+    ElectricalDriverMultiplier::~ElectricalDriverMultiplier()
+    {
+
+    }
+
+    double ElectricalDriverMultiplier::calculateDriveRes( double input_drive_res_) const
+    {
+        return input_drive_res_;
+    }
+
+    double ElectricalDriverMultiplier::calculateDelay() const
+    {
+        // This is just a model helper element, it does not contribute delay
+        return 0;
+    }
+
+    double ElectricalDriverMultiplier::calculateTransition() const
+    {
+        return getMaxUpstreamRes() * getTotalDownstreamCap();
+    }
+    
+    double ElectricalDriverMultiplier::getTotalDownstreamCap() const
+    {
+        // Finds the max of the load caps (as opposed to summing)
+        double max_cap = 0;
+        vector<ElectricalTimingNode*>* downstream_nodes = ElectricalTimingNode::getDownstreamNodes();
+        for (unsigned int i = 0; i < downstream_nodes->size(); ++i)
+        {
+            max_cap = std::max(max_cap, downstream_nodes->at(i)->getTotalDownstreamCap());
+        }
+        
+        return max_cap;
+    }    
+    
+} // namespace DSENT
+
+