Intel® Quartus® Prime Pro Edition User Guide: Timing Analyzer

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ID 683243
Date 10/04/2021
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Document Table of Contents
Document Table of Contents x
1. Timing Analysis Introduction 2. Using the Intel® Quartus® Prime Timing Analyzer A. Intel® Quartus® Prime Pro Edition User Guides
1. Timing Analysis Introduction x
1.1. Timing Analysis Basic Concepts 1.2. Timing Analysis Overview Document Revision History
1.1. Timing Analysis Basic Concepts x
1.1.1. Timing Path and Clock Analysis 1.1.2. Clock Setup Analysis 1.1.3. Clock Hold Analysis 1.1.4. Recovery and Removal Analysis 1.1.5. Multicycle Path Analysis 1.1.6. Metastability Analysis 1.1.7. Timing Pessimism 1.1.8. Clock-As-Data Analysis 1.1.9. Multicorner Timing Analysis 1.1.10. Time Borrowing
1.1.1. Timing Path and Clock Analysis x
1.1.1.1. The Timing Netlist 1.1.1.2. Timing Paths 1.1.1.3. Data and Clock Arrival Times 1.1.1.4. Launch and Latch Edges
1.1.5. Multicycle Path Analysis x
1.1.5.1. Multicycle Clock Hold 1.1.5.2. Multicycle Clock Setup
1.1.10. Time Borrowing x
1.1.10.1. Time Borrowing Limitations 1.1.10.2. Time Borrowing with Latches
2. Using the Intel® Quartus® Prime Timing Analyzer x
2.1. Timing Analysis Flow 2.2. Step 1: Specify Timing Analyzer Settings 2.3. Step 2: Specify Timing Constraints 2.4. Step 3: Run the Timing Analyzer 2.5. Step 4: Analyze Timing Reports 2.6. Applying Timing Constraints 2.7. Timing Analyzer Tcl Commands 2.8. Timing Analysis of Imported Compilation Results 2.9. Using the Intel® Quartus® Prime Timing Analyzer Document Revision History 2.10. Intel® Quartus® Prime Pro Edition User Guide: Timing Analyzer Archive
2.4. Step 3: Run the Timing Analyzer x
2.4.1. Setting the Operating Conditions 2.4.2. Enabling Time Borrowing Optimization
2.5. Step 4: Analyze Timing Reports x
2.5.1. Generating Timing Reports 2.5.2. Cross-Probing with Design Assistant 2.5.3. Launching Design Assistant from Timing Analyzer 2.5.4. Locating Timing Paths in Other Tools 2.5.5. Correlating Constraints to the Timing Report
2.5.1. Generating Timing Reports x
2.5.1.1. Report Fmax Summary 2.5.1.2. Report Timing 2.5.1.3. Report Data Delay 2.5.1.4. Report Clocks and Clock Networks 2.5.1.5. Report Clock Transfers 2.5.1.6. Report Logic Depth 2.5.1.7. Report Neighbor Paths 2.5.1.8. Report Register Spread 2.5.1.9. Report Route Net of Interest 2.5.1.10. Report Retiming Restrictions 2.5.1.11. Report Reset Statistics 2.5.1.12. Report Pipelining Information 2.5.1.13. Report Asynchronous CDC 2.5.1.14. Report CDC Viewer 2.5.1.15. Report Time Borrowing Data 2.5.1.16. Report Exceptions and Exceptions Reachability
2.5.1.8. Report Register Spread x
2.5.1.8.1. Registers with High Timing Path Endpoint Tension 2.5.1.8.2. Registers with High Immediate Fan-Out Tension
2.5.2. Cross-Probing with Design Assistant x
2.5.2.1. Cross-Probing from Design Assistant to Timing Analyzer
2.6. Applying Timing Constraints x
2.6.1. Recommended Initial SDC Constraints 2.6.2. SDC File Precedence 2.6.3. Modifying Iterative Constraints 2.6.4. Using Entity-bound SDC Files 2.6.5. Creating Clocks and Clock Constraints 2.6.6. Creating I/O Constraints 2.6.7. Creating Delay and Skew Constraints 2.6.8. Creating Timing Exceptions 2.6.9. Using Fitter Overconstraints 2.6.10. Example Circuit and SDC File
2.6.1. Recommended Initial SDC Constraints x
2.6.1.1. Create Clock (create_clock) 2.6.1.2. Derive PLL Clocks (derive_pll_clocks) 2.6.1.3. Derive Clock Uncertainty (derive_clock_uncertainty) 2.6.1.4. Set Clock Groups (set_clock_groups)
2.6.4. Using Entity-bound SDC Files x
2.6.4.1. Entity-bound Constraint Scope 2.6.4.2. Entity-bound Constraint Examples
2.6.5. Creating Clocks and Clock Constraints x
2.6.5.1. Creating Base Clocks 2.6.5.2. Creating Virtual Clocks 2.6.5.3. Creating Generated Clocks (create_generated_clock) 2.6.5.4. Deriving PLL Clocks 2.6.5.5. Creating Clock Groups (set_clock_groups) 2.6.5.6. Accounting for Clock Effect Characteristics 2.6.5.7. Constraining CDC Paths
2.6.5.1. Creating Base Clocks x
2.6.5.1.1. Automatic Clock Detection and Constraint Creation
2.6.5.2. Creating Virtual Clocks x
2.6.5.2.1. Specifying I/O Interface Uncertainty 2.6.5.2.2. I/O Interface Clock Uncertainty Example
2.6.5.3. Creating Generated Clocks (create_generated_clock) x
2.6.5.3.1. Clock Divider Example (-divide_by) 2.6.5.3.2. Clock Multiplexer Example
2.6.5.5. Creating Clock Groups (set_clock_groups) x
2.6.5.5.1. Exclusive Clock Groups (-logically_exclusive or -physically_exclusive) 2.6.5.5.2. Asynchronous Clock Groups (-asynchronous) 2.6.5.5.3. set_clock_groups Constraint Tips
2.6.5.6. Accounting for Clock Effect Characteristics x
2.6.5.6.1. Set Clock Latency (set_clock_latency) 2.6.5.6.2. Clock Uncertainty
2.6.6. Creating I/O Constraints x
2.6.6.1. Input Constraints (set_input_delay) 2.6.6.2. Output Constraints (set_output_delay)
2.6.7. Creating Delay and Skew Constraints x
2.6.7.1. Advanced I/O Timing and Board Trace Model Delay 2.6.7.2. Maximum Skew (set_max_skew) 2.6.7.3. Net Delay (set_net_delay)
2.6.8. Creating Timing Exceptions x
2.6.8.1. Timing Exception Precedence 2.6.8.2. False Paths (set_false_path) 2.6.8.3. Minimum and Maximum Delays 2.6.8.4. Multicycle Paths 2.6.8.5. Multicycle Exception Examples 2.6.8.6. Delay Annotation 2.6.8.7. Constraining Design Partition Ports
2.6.8.4. Multicycle Paths x
2.6.8.4.1. Common Multicycle Applications 2.6.8.4.2. Relaxing Setup with Multicycle (set_multicyle_path) 2.6.8.4.3. Accounting for a Phase Shift (-phase)
2.6.8.5. Multicycle Exception Examples x
2.6.8.5.1. Default Multicycle Analysis 2.6.8.5.2. End Multicycle Setup = 2 and End Multicycle Hold = 0 2.6.8.5.3. End Multicycle Setup = 2 and End Multicycle Hold = 1 2.6.8.5.4. Same Frequency Clocks with Destination Clock Offset 2.6.8.5.5. Destination Clock Frequency is a Multiple of the Source Clock Frequency 2.6.8.5.6. Destination Clock Frequency is a Multiple of the Source Clock Frequency with an Offset 2.6.8.5.7. Source Clock Frequency is a Multiple of the Destination Clock Frequency 2.6.8.5.8. Source Clock Frequency is a Multiple of the Destination Clock Frequency with an Offset
2.7. Timing Analyzer Tcl Commands x
2.7.1. The quartus_sta Executable 2.7.2. Collection Commands
2.7.2. Collection Commands x
2.7.2.1. Wildcard Characters 2.7.2.2. Adding and Removing Collection Items 2.7.2.3. Query of Collections 2.7.2.4. Using the get_pins Command
1. Timing Analysis Introduction
2. Using the Intel® Quartus® Prime Timing Analyzer
A. Intel® Quartus® Prime Pro Edition User Guides

2.7.2.4. Using the get_pins Command

The get_pins command supports options that control the matching behavior of the wildcard character (*). Depending on the combination of options you use, you can make the wildcard character (*) respect or ignore individual levels of hierarchy. The pipe character (|) indicates levels of hierarchy. By default, the wildcard character (*) matches only a single level of hierarchy.

These examples filter the following node and pin names to illustrate function:

  • lvl (a hierarchy level with the name lvl)
  • lvl|dataa (an input pin in the instance lvl)
  • lvl|datab (an input pin in the instance lvl)
  • lvl|cnod (a combinational node with the name cnod in the lvl instance)
  • lvl|cnod|datac (an input pin to the combinational node with the name cnod)
  • lvl|cnod|datad (an input pin to the combinational node cnod)
Table 34.  Sample Search Strings and Search Results
Search String Search Result
get_pins *|dataa lvl|dataa
get_pins *|datac <empty> 5
get_pins *|*|datac lvl|cnod|datac
get_pins lvl*|* lvl|dataa, lvl|datab
get_pins -hierarchical *|*|datac <empty>5
get_pins -hierarchical lvl|* lvl|dataa, lvl|datab
get_pins -hierarchical *|datac lvl|cnod|datac
get_pins -hierarchical lvl|*|datac <empty>5
get_pins -compatibility_mode *|datac lvl|cnod|datac 6
get_pins -compatibility_mode *|*|datac lvl|cnod|datac

The default method separates hierarchy levels of instances from nodes and pins with the pipe character (|). A match occurs when the levels of hierarchy match, and the string values including wildcards match the instance or pin names. For example, the command get_pins <instance_name>|*|datac returns all the datac pins for registers in a given instance. However, the command get_pins *|datac returns an empty collection because the levels of hierarchy do not match.

Use the -hierarchical matching scheme to return a collection of cells or pins in all hierarchies of your design.

For example, the command get_pins -hierarchical *|datac returns all the datac pins for all registers in your design. However, the command get_pins -hierarchical *|*|datac returns an empty collection because more than one pipe character (|) is not supported.

The -compatibility_mode option returns collections matching wildcard strings through any number of hierarchy levels. For example, an asterisk can match a pipe character when using -compatibility_mode.

5 The search result is <empty> because the wildcard character (*) does not match more than one hierarchy level, that a pipe character (|) indicates, by default. This command matches any pin with the name datac in instances at the top level of the design.
6 When you use -compatibility_mode, the Timing Analyzer does not treat pipe characters (|) as special characters when you use the characters with wildcards.
Level Two Title