1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
|
/* 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/MuxTreeSerializer.h"
#include <cmath>
#include "model/PortInfo.h"
#include "model/TransitionInfo.h"
#include "model/EventInfo.h"
#include "model/std_cells/StdCellLib.h"
#include "model/std_cells/StdCell.h"
#include "model/electrical/Multiplexer.h"
#include "model/timing_graph/ElectricalNet.h"
namespace DSENT
{
using std::ceil;
MuxTreeSerializer::MuxTreeSerializer(const String& instance_name_, const TechModel* tech_model_)
: ElectricalModel(instance_name_, tech_model_)
{
initParameters();
initProperties();
}
MuxTreeSerializer::~MuxTreeSerializer()
{}
void MuxTreeSerializer::initParameters()
{
addParameterName("InDataRate");
addParameterName("OutDataRate");
addParameterName("InBits"); //Output width will just be input width / serialization ratio
}
void MuxTreeSerializer::initProperties()
{
return;
}
MuxTreeSerializer* MuxTreeSerializer::clone() const
{
// TODO
return NULL;
}
void MuxTreeSerializer::constructModel()
{
// Get parameters
double in_data_rate = getParameter("InDataRate").toDouble();
double out_data_rate = getParameter("OutDataRate").toDouble();
unsigned int in_bits = getParameter("InBits").toUInt();
// Calculate serialization ratio
unsigned int serialization_ratio = (unsigned int) floor(out_data_rate / in_data_rate);
ASSERT(serialization_ratio == out_data_rate / in_data_rate,
"[Error] " + getInstanceName() + " -> Cannot have non-integer serialization ratios " +
"(" + (String) (in_data_rate / out_data_rate) + ")!");
// Calculate output width
ASSERT(floor((double) in_bits / serialization_ratio) == (double) in_bits / serialization_ratio,
"[Error] " + getInstanceName() + " -> Input width (" + (String) in_bits + ") " +
"must be a multiple of the serialization ratio (" + (String) serialization_ratio + ")!");
unsigned int output_bits = in_bits / serialization_ratio;
// Calculate the number of multiplexer stages
unsigned int number_stages = (unsigned int)ceil(log2((double) serialization_ratio));
// Store calculated values
getGenProperties()->set("SerializationRatio", serialization_ratio);
getGenProperties()->set("OutputBits", output_bits);
getGenProperties()->set("NumberStages", number_stages);
// Create ports
createInputPort("In", makeNetIndex(0, in_bits-1));
createInputPort("OutCK");
createOutputPort("Out", makeNetIndex(0, output_bits-1));
//Create energy, power, and area results
createElectricalResults();
createElectricalEventResult("Serialize");
getEventInfo("Serialize")->setTransitionInfo("OutCK", TransitionInfo(0.0, (double) serialization_ratio / 2.0, 0.0));
//Set conditions during idle state
getEventInfo("Idle")->setStaticTransitionInfos();
getEventInfo("Idle")->setTransitionInfo("OutCK", TransitionInfo(0.0, (double) serialization_ratio / 2.0, 0.0));
// Mark OutCK as a false path (since timing tool will do strange stuff due to all the clock divides and stuff)
getNet("OutCK")->setFalsePath(true);
// Create mux-tree instance
if (serialization_ratio == 1)
{
// No need to do anything, hohoho
assign("Out", "In");
}
else
{
// Create multiplexer
String mux_tree_name = "MuxTree";
ElectricalModel* mux_tree = new Multiplexer(mux_tree_name, getTechModel());
mux_tree->setParameter("NumberInputs", serialization_ratio);
mux_tree->setParameter("NumberBits", output_bits);
mux_tree->setParameter("BitDuplicate", "TRUE");
mux_tree->construct();
// Create nets
if (number_stages > 1)
createNet("MuxSel_b", makeNetIndex(0, number_stages-2));
createNet("MuxSel", makeNetIndex(0, number_stages-1));
assign("MuxSel", makeNetIndex(number_stages-1), "OutCK");
// Create reindexed net (to help out with indexing)
createNet("InTmp", makeNetIndex(0, in_bits-1));
for (unsigned int i = 0; i < serialization_ratio; ++i)
for (unsigned int j = 0; j < output_bits; ++j)
assign("InTmp", makeNetIndex(i*output_bits+j), "In", makeNetIndex(j*serialization_ratio+i));
// Connect ports
for (unsigned int i = 0; i < serialization_ratio; ++i)
portConnect(mux_tree, "In" + (String) i, "InTmp", makeNetIndex(i*output_bits, (i+1)*output_bits-1));
for (unsigned int i = 0; i < number_stages; ++i)
portConnect(mux_tree, "Sel" + (String) i, "MuxSel", makeNetIndex(i));
portConnect(mux_tree, "Out", "Out");
// Add subinstance and events
addSubInstances(mux_tree, 1.0);
addElectricalSubResults(mux_tree, 1.0);
// Add serialize event/power
getEventResult("Serialize")->addSubResult(mux_tree->getEventResult("Mux"), mux_tree_name, 1.0);
// Create clock dividers (assumes power of 2...), don't need divider for fastest output stage
for (unsigned int i = 0; i < number_stages - 1; ++i)
{
// Clk dividing registers
const String& clk_div_dff_name = "ClkDivDFF_" + (String) i;
StdCell* clk_div_dff = getTechModel()->getStdCellLib()->createStdCell("DFFQ", clk_div_dff_name);
clk_div_dff->construct();
portConnect(clk_div_dff, "D", "MuxSel_b", makeNetIndex(i));
portConnect(clk_div_dff, "Q", "MuxSel", makeNetIndex(i));
portConnect(clk_div_dff, "CK", "MuxSel", makeNetIndex(i+1));
addSubInstances(clk_div_dff, 1.0);
addElectricalSubResults(clk_div_dff, 1.0);
// Inversions
const String& clk_div_inv_name = "ClkDivINV_" + (String) i;
StdCell* clk_div_inv = getTechModel()->getStdCellLib()->createStdCell("INV", clk_div_inv_name);
clk_div_inv->construct();
portConnect(clk_div_inv, "A", "MuxSel", makeNetIndex(i));
portConnect(clk_div_inv, "Y", "MuxSel_b", makeNetIndex(i));
addSubInstances(clk_div_inv, 1.0);
addElectricalSubResults(clk_div_inv, 1.0);
getEventResult("Serialize")->addSubResult(clk_div_dff->getEventResult("CK"), clk_div_dff_name, 1.0);
getEventResult("Serialize")->addSubResult(clk_div_dff->getEventResult("DFFD"), clk_div_dff_name, 1.0);
getEventResult("Serialize")->addSubResult(clk_div_dff->getEventResult("DFFQ"), clk_div_dff_name, 1.0);
getEventResult("Serialize")->addSubResult(clk_div_inv->getEventResult("INV"), clk_div_inv_name, 1.0);
}
}
return;
}
void MuxTreeSerializer::propagateTransitionInfo()
{
// Get some generated properties
const unsigned int serialization_ratio = getGenProperties()->get("SerializationRatio");
const unsigned int number_stages = getGenProperties()->get("NumberStages");
// Set transition info of the mux tree and clock divide DFF
if (serialization_ratio == 1)
{
// If no serialization, then just propagate input transition info to output port
propagatePortTransitionInfo("Out", "In");
}
else
{
// Propagate transition probabilities to the mux tree
ElectricalModel* mux_tree = (ElectricalModel*) getSubInstance("MuxTree");
// All input ports of the mux have the same probability
for (unsigned int i = 0; i < serialization_ratio; ++i)
propagatePortTransitionInfo(mux_tree, "In" + (String) i, "In");
// Connect last stage of the mux
propagatePortTransitionInfo(mux_tree, "Sel" + (String) (number_stages - 1), "OutCK");
// Keep track of the last clock divider
ElectricalModel* last_clk_div_dff = NULL;
// Find P01 of OutCK
double last_P01_CK = getInputPort("OutCK")->getTransitionInfo().getNumberTransitions01();
// Start from the last stage (since it is the stage with no clock division)
for (unsigned int i = 0; i < number_stages - 1; ++i)
{
const String& clk_div_dff_name = "ClkDivDFF_" + (String) (number_stages - i - 2);
const String& clk_div_inv_name = "ClkDivINV_" + (String) (number_stages - i - 2);
ElectricalModel* clk_div_dff = (ElectricalModel*) getSubInstance(clk_div_dff_name);
if (last_clk_div_dff == NULL)
propagatePortTransitionInfo(clk_div_dff, "CK", "OutCK");
else
propagatePortTransitionInfo(clk_div_dff, "CK", last_clk_div_dff, "Q");
// Since it is a clock divider, P01 is D and Q are simply half the P01 of D and Q of
// the input clock
if (last_P01_CK != 0) clk_div_dff->getInputPort("D")->setTransitionInfo(TransitionInfo(0.0, last_P01_CK * 0.5, 0.0));
else clk_div_dff->getInputPort("D")->setTransitionInfo(TransitionInfo(0.5, 0.0, 0.5));
clk_div_dff->use();
ElectricalModel* clk_div_inv = (ElectricalModel*) getSubInstance(clk_div_inv_name);
propagatePortTransitionInfo(clk_div_inv, "A", clk_div_dff, "Q");
clk_div_inv->use();
// Connect select port of the mux
propagatePortTransitionInfo(mux_tree, "Sel" + (String) (number_stages - i - 2), clk_div_dff, "Q");
// Clk divide by 2;
last_P01_CK = last_P01_CK * 0.5;
// Remember the last clk div DFF
last_clk_div_dff = clk_div_dff;
}
mux_tree->use();
// Set output transition info to be the output transition info of the mux tree
propagatePortTransitionInfo("Out", mux_tree, "Out");
}
return;
}
} // namespace DSENT
|
