PLI 1.0™ Application Note - Back
Annotation and Delay Calculation
Product Version 3.2
October 2000
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Back Annotation and Delay Calculation
Contents
1 |
|
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
. 7 |
About These Application Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
7 |
What Is a Cell? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
8 |
Cell Interconnect Delays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
8 |
What Is Delay Back Annotation? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
9 |
What Is Delay Calculation? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
10 |
Prerequisites and Related Reading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
11 |
2 |
|
Creating a Back Annotator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
13 |
The Programming Language Interface (PLI) Mechanism . . . . . . . . . . . . . . . . . . . . . . . . |
13 |
PLI Access Routines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
14 |
Access Routine Families . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
15 |
Required UTILITY Routines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
15 |
Access to Timing Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
16 |
Identifying Cells and Manipulating Cell Definition Data . . . . . . . . . . . . . . . . . . . . . . . |
17 |
Effect of Source Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
18 |
Where to Look for More Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
19 |
3 |
|
Back Annotating Delays. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
20 |
Examples Used in This Chapter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
20 |
Retrieving a Handle to the Object Associated with the Delay . . . . . . . . . . . . . . . . . . . . . |
26 |
Retrieving a Handle to a Net . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
26 |
Retrieving a Handle to a Module Path Delay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
27 |
Retrieving a Handle to a Timing Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
29 |
Annotating the Delay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
33 |
Determining How and Where to Place Delays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
33 |
Annotating to Cells with Path Delays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
34 |
October 2000 |
3 |
Product Version 3.2 |
Back Annotation and Delay Calculation
Annotating to Cells with Lumped or Distributed Delays . . . . . . . . . . . . . . . . . . . . . . . |
38 |
Libraries with Mixed Cell Timing Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
40 |
Annotating to Timing Checks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
41 |
4 |
|
Calculating Delays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
. 42 |
Examples Used in This Chapter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
42 |
Scanning Cell Instances Within the Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
48 |
Determining the Scope of the Delay Calculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
48 |
Scan Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
50 |
Scanning Objects Within the Cell Instance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
52 |
Relationship to Modeling Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
52 |
Scanning Path Delays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
52 |
Scanning Cell Output Ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
54 |
Libraries with Mixed Cell Timing Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
56 |
Providing and Retrieving Delay |
|
Calculation Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
56 |
Types of Data Needed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
56 |
Coding Data into Cell Descriptions (Attributes) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
56 |
Retrieving Cell I/O Load Factors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
61 |
Load Due to Interconnect Wire . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
63 |
Calculating and Annotating the Delays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
85 |
Calculating the Delays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
85 |
Annotating the Delays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
86 |
5 |
|
Example Listings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
93 |
Delay Back Annotators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
93 |
Cell Output Nets to Lumped or Distributed Delay Cells . . . . . . . . . . . . . . . . . . . . . . . |
93 |
Interconnect Nets to Lumped or Distributed Delay Cells . . . . . . . . . . . . . . . . . . . . . . |
95 |
Cell Output Nets to Path Delay Cells . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
97 |
Interconnect Nets to Path Delay Cells . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
99 |
Explicitly Identified Path Delays and Timing Checks . . . . . . . . . . . . . . . . . . . . . . . . |
102 |
Delay Calculators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
105 |
Creating and Extracting Data From a Hash Table . . . . . . . . . . . . . . . . . . . . . . . . . . |
105 |
October 2000 |
4 |
Product Version 3.2 |
Back Annotation and Delay Calculation |
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Random Cell Scan and Cell Output Nets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
109 |
Random Cell Scan and Cell Interconnect Nets . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
118 |
Delay Calculation Driven by Cell Output Nets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . |
128 |
Delay Calculation Driven by a Cell Interconnect Nets . . . . . . . . . . . . . . . . . . . . . . . |
135 |
Index.............................................................................................................................. |
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Back Annotation and Delay Calculation
October 2000 |
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