© 2003 Xilinx, Inc. All Rights Reserved

Reading Reports

Xilinx:

This module was completely redone. Please translate entire module

Some pages are the same. They are noted in the module

Xilinx:

This module was completely redone. Please translate entire module

Some pages are the same. They are noted in the module

FPGA Design Flow Workshop

Reading Reports 6 - 2 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Objectives

After completing this module, you will be able to:• Determine whether a design met your area goals• Determine whether a design met your performance goals

Xilinx:

all new bullets

Xilinx:

all new bullets

Reading Reports 6 - 3 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Outline

• Introduction• Area Goals• Performance Goals• Summary

Reading Reports 6 - 4 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Introduction

• After you have implemented your design, how can you tell whether the implementation was successful?

• First and foremost, how do you define a successful design?

• Answer: A successful design means the design...– Fits into the device– Achieves performance goals

Reading Reports 6 - 5 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Outline

• Introduction• Area Goals• Performance Goals• Summary

Reading Reports 6 - 6 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Area Goals

• How do we know if the design fits into the device?

• How do we know if there is room in the device for more logic? If there is, exactly how much space is available?

• If the design fits into the device, was it able to route completely?

Reading Reports 6 - 7 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Area Goals

• How do we know if the design fits into the device?– Information can be found in the Map Report or the Place & Route Report

• How do we know if there is room in the device for more logic? If there is, exactly how much space is available?

– Information can be found in the Map Report or the Place & Route Report

• If the design fits into the device, was it able to route completely?– Information can be found in the Place & Route Report

Reading Reports 6 - 8 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Map Report

• Map Report contents– Command line options for the map program– Design summary

• List of how many device resources are used– Errors and warnings– Removed logic summary

• List of logic that was removed due to sourceless or loadless nets– IOB properties

• Indicates whether an I/O flip-flop is used• List of attributes on each I/O pin

Xilinx:

Same as v4 slide 6-10

Removed last bullet about Post-map Static Timing Report

Xilinx:

Same as v4 slide 6-10

Removed last bullet about Post-map Static Timing Report

Reading Reports 6 - 9 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Map Report

• Map Report– <design>.mrp

• It is useful to review this report before proceeding to Place & Route

– Especially for large or high-speed designs

– Ensure device has enough resources

Reading Reports 6 - 10 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Map Report Questions

Open the Map Report from the Tool Flow lab

• How many slices were used?

• How many IOBs were used?

• Were there any errors, warnings, or informational messages?

Xilinx:

Same as v4 slide 6-11

Xilinx:

Same as v4 slide 6-11

Reading Reports 6 - 11 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Answers

• How many slices were used (Number of occupied Slices)?– Virtex-II

• 162 (VHDL)• 75 (Verilog)

– Spartan-3• 164 (VHDL)• 75 (Verilog)

• How many IOBs were used?– 17 (same for all versions)

• Were there any errors, warnings, or informational messages?– Three informational messages (same for all versions)

Reading Reports 6 - 12 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Place & Route Report

• Place & Route Report contents – Command line options for the PAR program– Errors and warnings– Device utilization summary

• Similar to the Design Summary from the Map Report– Unrouted nets– Timing summary

• Statistics on average routing delays• Performance versus constraints if the design contains timing constraints

Xilinx:

same as v4 slide 6-17

Xilinx:

same as v4 slide 6-17

Reading Reports 6 - 13 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Place & Route Report

• Place & Route Report– <design>.par

Reading Reports 6 - 14 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Place & Route Report Questions

Open the Place & Route Report from the Tool Flow lab

• Does the Device Utilization Summary agree with the Map Report?

• Are there any unrouted signals?

Reading Reports 6 - 15 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Answers

• Does the Device Utilization Summary agree with the Map Report?– Yes

• Are there any unrouted signals?– No

Reading Reports 6 - 16 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Outline

• Introduction• Area Goals• Performance Goals• Summary

Reading Reports 6 - 17 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

CommunicatingPerformance Goals

• Where would you look to find reasonable values for your timing constraints?

• Answer: Post-Map Static Timing Report

Reading Reports 6 - 18 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Post-Map Static Timing Report

• The Post-Map Static Timing Report indicates whether your constraints are reasonable

– Contains actual block delays and 0.1 ns net delays• What is reasonable? Use the 60/40 rule:

– If less than 60 percent of the timing budget is used for logic delays, the Place & Route tools should be able to meet the constraint easily

– Between 60 to 80 percent, software run time will increase– Greater than 80 percent, the tools may have trouble meeting your goals

Xilinx:

similar to v4 slide 6-30

Note: values in sub-bullets are

changed

Xilinx:

similar to v4 slide 6-30

Note: values in sub-bullets are

changed

Reading Reports 6 - 19 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Handling Unreasonable Constraints

• Re-evaluate the constraints: Is the design over-constrained?– Yes: Consider using advanced constraints– No: Redesign logic or pipeline to reduce the number of logic levels in long

paths

Xilinx:

same as v4 slide 6-31

Xilinx:

same as v4 slide 6-31

Reading Reports 6 - 20 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Timing Reports

• Post-Map Static Timing Report created during Map process

– <design>.twx– Not created by default– Double-click the process to

create this report– Double-click on the report to

view it in the Timing Analyzer

Reading Reports 6 - 21 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Timing Reports

• Timing Report contents (for designs with constraints)– Command line options for the trce program– Timing Constraints section

• Summary of each timing constraint (if you have any)• Details on paths that fail to meet constraints

– Data sheet section• Setup/hold, clock to pad, timing between clock domains, and pad-to-pad delay

information• Organized in easy-to-read table format

– Timing Summary section• Number of errors and Timing Score

Xilinx:

same as v4 slide 6-28

Xilinx:

same as v4 slide 6-28

Reading Reports 6 - 22 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Timing Reports

• Timing Reports can be viewed using the Timing Analyzer– Creating custom reports with the Timing Analyzer is covered in the

Designing for Performance course• Note: Timing Reports can be created for designs without constraints

– Xilinx, however, recommends using timing constraints to meet performance goals

Xilinx:

same as v4 slide 6-29

Xilinx:

same as v4 slide 6-29

Reading Reports 6 - 23 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Evaluating Performance Goals

• Now that you have entered constraints, how do you know if the constraints were met?

• Answer: Place & Route Report or Post-Place & Route Static Timing Report

Reading Reports 6 - 24 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Post-Place & Route Timing Report

• Post-Place & Route Static Timing Report

– <design>.twx– Created by default

Reading Reports 6 - 25 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Post-Place & Route Static Timing Report

• The Post-Place & Route Static Timing Report indicates whether your constraints were actually met

– Contains actual block delays and actual net delays calculated from Place & Route

– Used for static timing analysis after Place & Route

Xilinx:

same as v4 slide 6-32

Xilinx:

same as v4 slide 6-32

Reading Reports 6 - 26 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Timing Report Question

Open the Post-Place & Route Static Timing Report from the Tool Flow lab

• What is the minimum clock period for this design (clock to setup value for wr_clk_in)?

Reading Reports 6 - 27 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Answer

• What is the minimum clock period for this design (clock to setup value for wr_clk_in)?

– Virtex-II• 22.084 ns (VHDL)• 8.025 ns (Verilog)

– Spartan-3• 26.786 ns (VHDL)• 10.988 ns (Verilog)

• Notice there are no timing constraints in the design; otherwise, they would have been reported

Reading Reports 6 - 28 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Pinout Information

• Where can I get pinout information to start the board layout?

• Answer: Pad Report

Reading Reports 6 - 29 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Pad Report

• Plain text Pad Report– <design>_pad.txt– Viewed in the Project Navigator

window– Sorted by pin number only

• Pad Report– <design>.pad, <design>_pad.csv– This report must be viewed in a

spreadsheet tool• Delimiters: | (.pad) or comma (.csv)

– Allows data sorting by various fields• Pin number, signal name, I/O

standard, data flow direction, etc

Reading Reports 6 - 30 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Pad Report Questions

Open the Pad Report from the Tool Flow lab.

• What pin location was assigned to “reset”?

• What is on pin H8?

Reading Reports 6 - 31 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Answers

• What pin location was assigned to “reset”?– Virtex-II

• D9 (VHDL)• C12 (Verilog)

– Spartan-3• P16 (VHDL)• P11 (Verilog)

• What is on pin H8?– GND

Reading Reports 6 - 32 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Outline

• Introduction• Area Goals• Performance Goals• Summary

Reading Reports 6 - 34 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Review Questions

• How do you determine whether your timing constraints are reasonable? (Hint: which report do you review?)

• To estimate the amount of available resources you have left, do you need to fully implement your design? Why or why not?

Reading Reports 6 - 35 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Answers

• How do you determine whether your timing constraints are reasonable? (Hint: which report do you review?)

– Use the Post-Map Static Timing Report– You must double-click the Generate Post-Map Static Timing process to

create this report (it is not created by default)• This process is underneath the Map process

• To estimate the amount of available resources you have left, do you need to fully implement your design? Why or why not?

– No. You have to implement through the Translate and Map processes because the Design Summary in the Map Report shows you the available resources left in the device

Reading Reports 6 - 36 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Summary

• A successful implementation means that your design meets your area and performance objectives

• The Map and PAR Report provides resource utilization and availability

• The Post-Map Static Timing Report gives you information to create reasonable timing constraints

• The Post-Place & Route Static Timing Report informs you whether your timing constraints were met

Reading Reports 6 - 37 © 2003 Xilinx, Inc. All Rights Reserved For Academic Use Only

Where Can I Learn More?

• Development System Reference Guide– http://www.support.xilinx.com Software Manuals