gem5/ext/dsent/model/electrical/Decoder.cc
Nilay Vaish c1aecc05e6 ext: dsent: adds a Python interface, drops C++ one
This patch extensively modifies DSENT so that it can be accessed using Python.
To access the Python interface, DSENT needs to compiled as a shared library.
For this purpose a CMakeLists.txt file has been added.  Some of the code that
is not required is being removed.
2014-10-11 16:16:00 -05:00

256 lines
9.7 KiB
C++

/* Copyright (c) 2012 Massachusetts Institute of Technology
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "model/electrical/Decoder.h"
#include <cmath>
#include "model/PortInfo.h"
#include "model/EventInfo.h"
#include "model/TransitionInfo.h"
#include "model/std_cells/StdCellLib.h"
#include "model/std_cells/StdCell.h"
namespace DSENT
{
using std::ceil;
Decoder::Decoder(const String& instance_name_, const TechModel* tech_model_)
: ElectricalModel(instance_name_, tech_model_)
{
initParameters();
initProperties();
}
Decoder::~Decoder()
{}
void Decoder::initParameters()
{
addParameterName("NumberOutputs");
}
void Decoder::initProperties()
{
return;
}
Decoder* Decoder::clone() const
{
// TODO
return NULL;
}
void Decoder::constructModel()
{
// Get parameters
unsigned int number_outputs = getParameter("NumberOutputs").toUInt();
ASSERT(number_outputs > 0, "[Error] " + getInstanceName() + " -> Number of outputs must be > 0!");
unsigned int number_addr_bits = (unsigned int)ceil(log2(number_outputs));
// Create ports
for(unsigned int i = 0; i < number_addr_bits; ++i)
{
createInputPort("Addr" + (String)i);
}
for(unsigned int i = 0; i < number_outputs; ++i)
{
createOutputPort("Out" + (String)i);
}
// Create energy, power, and area results
createElectricalResults();
createElectricalEventResult("Decode");
Result* decode_event = getEventResult("Decode");
getEventInfo("Idle")->setStaticTransitionInfos();
if(number_addr_bits == 0)
{
// Do not need a decoder
}
else if(number_addr_bits == 1)
{
const String& inv0_name = "Inv0";
StdCell* inv0 = getTechModel()->getStdCellLib()->createStdCell("INV", inv0_name);
inv0->construct();
// Connect inputs and outputs
portConnect(inv0, "A", "Addr0");
portConnect(inv0, "Y", "Out0");
assign("Out1", "Addr0");
// Add area, power, and event results
addSubInstances(inv0, 1.0);
addElectricalSubResults(inv0, 1.0);
decode_event->addSubResult(inv0->getEventResult("INV"), inv0_name, 1.0);
}
else
{
unsigned int number_addr_bits_0 = (unsigned int)ceil((double)number_addr_bits / 2.0);
unsigned int number_addr_bits_1 = (unsigned int)floor((double)number_addr_bits / 2.0);
unsigned int number_outputs_0 = (unsigned int)pow(2.0, number_addr_bits_0);
unsigned int number_outputs_1 = (unsigned int)ceil((double)number_outputs / (double)number_outputs_0);
const String& dec0_name = "Dec_way0";
const String& dec1_name = "Dec_way1";
vector<String> nand2_names(number_outputs, "");
vector<String> inv_names(number_outputs, "");
for(unsigned int i = 0; i < number_outputs; ++i)
{
nand2_names[i] = "NAND2_" + (String)i;
inv_names[i] = "INV_" + (String)i;
}
Decoder* dec0 = new Decoder(dec0_name, getTechModel());
dec0->setParameter("NumberOutputs", number_outputs_0);
dec0->construct();
Decoder* dec1 = new Decoder(dec1_name, getTechModel());
dec1->setParameter("NumberOutputs", number_outputs_1);
dec1->construct();
vector<StdCell*> nand2s(number_outputs, NULL);
vector<StdCell*> invs(number_outputs, NULL);
for(unsigned int i = 0; i < number_outputs; ++i)
{
nand2s[i] = getTechModel()->getStdCellLib()->createStdCell("NAND2", nand2_names[i]);
nand2s[i]->construct();
invs[i] = getTechModel()->getStdCellLib()->createStdCell("INV", inv_names[i]);
invs[i]->construct();
}
// Connect inputs and outputs
for(unsigned int i = 0; i < number_addr_bits_0; ++i)
{
portConnect(dec0, "Addr" + (String)i, "Addr" + (String)i);
}
for(unsigned int i = 0; i < number_addr_bits_1; ++i)
{
portConnect(dec1, "Addr" + (String)i, "Addr" + (String)(i + number_addr_bits_0));
}
for(unsigned int i = 0; i < number_outputs_0; ++i)
{
createNet("way0Out" + (String)i);
portConnect(dec0, "Out" + (String)i, "way0Out" + (String)i);
}
for(unsigned int i = 0; i < number_outputs_1; ++i)
{
createNet("way1Out" + (String)i);
portConnect(dec1, "Out" + (String)i, "way1Out" + (String)i);
}
for(unsigned int i = 0; i < number_outputs; ++i)
{
createNet("nand" + (String)i + "Out");
portConnect(nand2s[i], "A", "way0Out" + (String)(i%number_outputs_0));
portConnect(nand2s[i], "B", "way1Out" + (String)((unsigned int)floor(i/number_outputs_0)));
portConnect(nand2s[i], "Y", "nand" + (String)i + "Out");
portConnect(invs[i], "A", "nand" + (String)i + "Out");
portConnect(invs[i], "Y", "Out" + (String)i);
}
// Add area, power, and event results
addSubInstances(dec0, 1.0);
addElectricalSubResults(dec0, 1.0);
decode_event->addSubResult(dec0->getEventResult("Decode"), dec0_name, 1.0);
addSubInstances(dec1, 1.0);
addElectricalSubResults(dec1, 1.0);
decode_event->addSubResult(dec1->getEventResult("Decode"), dec1_name, 1.0);
for(unsigned int i = 0; i < number_outputs; ++i)
{
addSubInstances(nand2s[i], 1.0);
addElectricalSubResults(nand2s[i], 1.0);
decode_event->addSubResult(nand2s[i]->getEventResult("NAND2"), nand2_names[i], 1.0);
addSubInstances(invs[i], 1.0);
addElectricalSubResults(invs[i], 1.0);
decode_event->addSubResult(invs[i]->getEventResult("INV"), inv_names[i], 1.0);
}
}
return;
}
void Decoder::propagateTransitionInfo()
{
// The only thing can be updated are the input probabilities
unsigned int number_outputs = getParameter("NumberOutputs").toUInt();
unsigned int number_addr_bits = (unsigned int)ceil(log2(number_outputs));
if(number_addr_bits == 0)
{
// Do not need a decoder
}
else if(number_addr_bits == 1)
{
ElectricalModel* inv0 = (ElectricalModel*)getSubInstance("Inv0");
propagatePortTransitionInfo(inv0, "A", "Addr0");
inv0->use();
// Since # addr bits is 1, the output 0 is directly connected
propagatePortTransitionInfo("Out0", inv0, "Y");
propagatePortTransitionInfo("Out1", "Addr0");
}
else
{
unsigned int number_addr_bits_0 = (unsigned int)ceil((double)number_addr_bits / 2.0);
unsigned int number_addr_bits_1 = (unsigned int)floor((double)number_addr_bits / 2.0);
unsigned int number_outputs_0 = (unsigned int)pow(2.0, number_addr_bits_0);
// Update decoders with probabilities
ElectricalModel* dec0 = (ElectricalModel*)getSubInstance("Dec_way0");
for(unsigned int i = 0; i < number_addr_bits_0; ++i)
{
propagatePortTransitionInfo(dec0, "Addr" + (String)i, "Addr" + (String)i);
}
dec0->use();
ElectricalModel* dec1 = (ElectricalModel*)getSubInstance("Dec_way1");
for(unsigned int i = 0; i < number_addr_bits_1; ++i)
{
propagatePortTransitionInfo(dec1, "Addr" + (String)i, "Addr" + (String)(i + number_addr_bits_0));
}
dec1->use();
for(unsigned int i = 0; i < number_outputs; ++i)
{
ElectricalModel* nand2 = (ElectricalModel*)getSubInstance("NAND2_" + (String)i);
propagatePortTransitionInfo(nand2, "A", dec0, "Out" + (String)(i%number_outputs_0));
propagatePortTransitionInfo(nand2, "B", dec1, "Out" + (String)((unsigned int)floor(i/number_outputs_0)));
nand2->use();
ElectricalModel* inv = (ElectricalModel*)getSubInstance("INV_" + (String)i);
propagatePortTransitionInfo(inv, "A", nand2, "Y");
inv->use();
propagatePortTransitionInfo("Out" + (String)i, inv, "Y");
}
}
return;
}
} // namespace DSENT