Finding Maximum delay through FPGA design from a VHDL code written in Xilinx software

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i am working on AES code and my aim is to create an architecture which will give the fastest performance. hence i need to determine the delay from the time input is given and the final output is obtained. the design is to be implemented on fpga. i need to find the delay via xilinx simulation and design summary. however i fail to understand the various reports.

for model one i am giving the 3 reports from design summary.

  1. synthesis report
  2. place and route report
  3. static timing report

static timing report

--------------------------------------------------------------------------------
Release 9.2i Trace 
Copyright (c) 1995-2007 Xilinx, Inc.  All rights reserved.

C:\Xilinx92i\bin\nt\trce.exe -ise C:/Xilinx92i/sbox/sbox.ise -intstyle ise -e 3
-s 5 -xml dynamic5stage dynamic5stage.ncd -o dynamic5stage.twr
dynamic5stage.pcf

Design file:              dynamic5stage.ncd
Physical constraint file: dynamic5stage.pcf
Device,package,speed:     xc3s200,pq208,-5 (PRODUCTION 1.39 2007-04-13)
Report level:             error report

Environment Variable      Effect 
--------------------      ------ 
NONE                      No environment variables were set
--------------------------------------------------------------------------------

INFO:Timing:2698 - No timing constraints found, doing default enumeration.
INFO:Timing:2752 - To get complete path coverage, use the unconstrained paths 
   option. All paths that are not constrained will be reported in the 
   unconstrained paths section(s) of the report.
INFO:Timing:3339 - The clock-to-out numbers in this timing report are based on 
   a 50 Ohm transmission line loading model.  For the details of this model, 
   and for more information on accounting for different loading conditions, 
   please see the device datasheet.



Data Sheet report:
-----------------
All values displayed in nanoseconds (ns)

Setup/Hold to clock SYS_CLK
------------+------------+------------+------------------+--------+
            |  Setup to  |  Hold to   |                  | Clock  |
Source      | clk (edge) | clk (edge) |Internal Clock(s) | Phase  |
------------+------------+------------+------------------+--------+
BYTE_IN<0>  |    2.659(R)|    0.515(R)|SYS_CLK_BUFGP     |   0.000|
BYTE_IN<1>  |    3.216(R)|    0.381(R)|SYS_CLK_BUFGP     |   0.000|
BYTE_IN<2>  |    3.373(R)|    0.453(R)|SYS_CLK_BUFGP     |   0.000|
BYTE_IN<3>  |    3.155(R)|    0.001(R)|SYS_CLK_BUFGP     |   0.000|
BYTE_IN<4>  |    3.419(R)|    0.663(R)|SYS_CLK_BUFGP     |   0.000|
BYTE_IN<5>  |    4.055(R)|    0.118(R)|SYS_CLK_BUFGP     |   0.000|
BYTE_IN<6>  |    3.389(R)|    0.545(R)|SYS_CLK_BUFGP     |   0.000|
BYTE_IN<7>  |    3.151(R)|    0.389(R)|SYS_CLK_BUFGP     |   0.000|
RST         |    2.750(R)|    0.970(R)|SYS_CLK_BUFGP     |   0.000|
s           |    3.140(R)|    0.344(R)|SYS_CLK_BUFGP     |   0.000|
------------+------------+------------+------------------+--------+

Clock SYS_CLK to Pad
---------------+------------+------------------+--------+
               | clk (edge) |                  | Clock  |
Destination    |   to PAD   |Internal Clock(s) | Phase  |
---------------+------------+------------------+--------+
SUB_BYTE_OUT<0>|    6.404(R)|SYS_CLK_BUFGP     |   0.000|
SUB_BYTE_OUT<1>|    6.404(R)|SYS_CLK_BUFGP     |   0.000|
SUB_BYTE_OUT<2>|    6.404(R)|SYS_CLK_BUFGP     |   0.000|
SUB_BYTE_OUT<3>|    6.404(R)|SYS_CLK_BUFGP     |   0.000|
SUB_BYTE_OUT<4>|    6.404(R)|SYS_CLK_BUFGP     |   0.000|
SUB_BYTE_OUT<5>|    6.404(R)|SYS_CLK_BUFGP     |   0.000|
SUB_BYTE_OUT<6>|    6.404(R)|SYS_CLK_BUFGP     |   0.000|
SUB_BYTE_OUT<7>|    6.403(R)|SYS_CLK_BUFGP     |   0.000|
---------------+------------+------------------+--------+

Clock to Setup on destination clock SYS_CLK
---------------+---------+---------+---------+---------+
               | Src:Rise| Src:Fall| Src:Rise| Src:Fall|
Source Clock   |Dest:Rise|Dest:Rise|Dest:Fall|Dest:Fall|
---------------+---------+---------+---------+---------+
SYS_CLK        |    3.612|         |         |         |
---------------+---------+---------+---------+---------+


Analysis completed Sat Nov 29 11:39:23 2014 
--------------------------------------------------------------------------------

Trace Settings:
-------------------------
Trace Settings 

Peak Memory Usage: 93 MB

place & route report

Release 9.2i par J.36
Copyright (c) 1995-2007 Xilinx, Inc.  All rights reserved.

ACER-PC::  Sat Nov 29 11:38:52 2014

par -w -intstyle ise -ol std -t 1 dynamic5stage_map.ncd dynamic5stage.ncd
dynamic5stage.pcf 


Constraints file: dynamic5stage.pcf.
Loading device for application Rf_Device from file '3s200.nph' in environment C:\Xilinx92i.
   "dynamic5stage" is an NCD, version 3.1, device xc3s200, package pq208, speed -5

Initializing temperature to 85.000 Celsius. (default - Range: 0.000 to 85.000 Celsius)
Initializing voltage to 1.140 Volts. (default - Range: 1.140 to 1.260 Volts)

INFO:Par:282 - No user timing constraints were detected or you have set the option to ignore timing constraints ("par
   -x"). Place and Route will run in "Performance Evaluation Mode" to automatically improve the performance of all
   internal clocks in this design. The PAR timing summary will list the performance achieved for each clock. Note: For
   the fastest runtime, set the effort level to "std".  For best performance, set the effort level to "high". For a
   balance between the fastest runtime and best performance, set the effort level to "med".

Device speed data version:  "PRODUCTION 1.39 2007-04-13".


Device Utilization Summary:

   Number of BUFGMUXs                        1 out of 8      12%
   Number of External IOBs                  19 out of 141    13%
      Number of LOCed IOBs                   0 out of 19      0%

   Number of Slices                         62 out of 1920    3%
      Number of SLICEMs                      0 out of 960     0%



Overall effort level (-ol):   Standard 
Placer effort level (-pl):    High 
Placer cost table entry (-t): 1
Router effort level (-rl):    Standard 



REAL time consumed by placer: 16 secs 
CPU  time consumed by placer: 10 secs 
Writing design to file dynamic5stage.ncd


Total REAL time to Placer completion: 17 secs 
Total CPU time to Placer completion: 11 secs 

Starting Router

Phase 1: 482 unrouted;       REAL time: 18 secs 

Phase 2: 436 unrouted;       REAL time: 18 secs 

Phase 3: 178 unrouted;       REAL time: 18 secs 

Phase 4: 178 unrouted; (0)      REAL time: 18 secs 

Phase 5: 180 unrouted; (0)      REAL time: 18 secs 

Phase 6: 0 unrouted; (87)      REAL time: 19 secs 

Phase 7: 0 unrouted; (87)      REAL time: 19 secs 

Updating file: dynamic5stage.ncd with current fully routed design.

Phase 8: 0 unrouted; (0)      REAL time: 20 secs 

Phase 9: 0 unrouted; (0)      REAL time: 20 secs 


Total REAL time to Router completion: 20 secs 
Total CPU time to Router completion: 13 secs 

Partition Implementation Status
-------------------------------

  No Partitions were found in this design.

-------------------------------

Generating "PAR" statistics.

**************************
Generating Clock Report
**************************

+---------------------+--------------+------+------+------------+-------------+
|        Clock Net    |   Resource   |Locked|Fanout|Net Skew(ns)|Max Delay(ns)|
+---------------------+--------------+------+------+------------+-------------+
|       SYS_CLK_BUFGP |      BUFGMUX6| No   |   45 |  0.036     |  0.916      |
+---------------------+--------------+------+------+------------+-------------+

* Net Skew is the difference between the minimum and maximum routing
only delays for the net. Note this is different from Clock Skew which
is reported in TRCE timing report. Clock Skew is the difference between
the minimum and maximum path delays which includes logic delays.


   The Delay Summary Report


The NUMBER OF SIGNALS NOT COMPLETELY ROUTED for this design is: 0

   The AVERAGE CONNECTION DELAY for this design is:        0.832
   The MAXIMUM PIN DELAY IS:                               2.272
   The AVERAGE CONNECTION DELAY on the 10 WORST NETS is:   1.786

   Listing Pin Delays by value: (nsec)

    d < 1.00   < d < 2.00  < d < 3.00  < d < 4.00  < d < 5.00  d >= 5.00
   ---------   ---------   ---------   ---------   ---------   ---------
         337         142           2           0           0           0

Timing Score: 0

Asterisk (*) preceding a constraint indicates it was not met.
   This may be due to a setup or hold violation.

------------------------------------------------------------------------------------------------------
  Constraint                                |  Check  | Worst Case |  Best Case | Timing |   Timing   
                                            |         |    Slack   | Achievable | Errors |    Score   
------------------------------------------------------------------------------------------------------
  Autotimespec constraint for clock net SYS | SETUP   |         N/A|     3.612ns|     N/A|           0
  _CLK_BUFGP                                | HOLD    |     0.702ns|            |       0|           0
------------------------------------------------------------------------------------------------------


All constraints were met.
INFO:Timing:2761 - N/A entries in the Constraints list may indicate that the 
   constraint does not cover any paths or that it has no requested value.


Generating Pad Report.

All signals are completely routed.

Total REAL time to PAR completion: 21 secs 
Total CPU time to PAR completion: 15 secs 

Peak Memory Usage:  136 MB

Placement: Completed - No errors found.
Routing: Completed - No errors found.

Number of error messages: 0
Number of warning messages: 0
Number of info messages: 1

Writing design to file dynamic5stage.ncd



PAR done!

synthesis report

Release 9.2i - xst J.36
Copyright (c) 1995-2007 Xilinx, Inc.  All rights reserved.
--> Parameter TMPDIR set to ./xst/projnav.tmp
CPU : 0.00 / 4.04 s | Elapsed : 0.00 / 4.00 s

--> Parameter xsthdpdir set to ./xst
CPU : 0.00 / 4.04 s | Elapsed : 0.00 / 4.00 s

--> Reading design: dynamic5stage.prj



=========================================================================
*                      Synthesis Options Summary                        *
=========================================================================
---- Source Parameters
Input File Name                    : "dynamic5stage.prj"
Input Format                       : mixed
Ignore Synthesis Constraint File   : NO

---- Target Parameters
Output File Name                   : "dynamic5stage"
Output Format                      : NGC
Target Device                      : xc3s200-5-pq208

---- Source Options
Top Module Name                    : dynamic5stage
Automatic FSM Extraction           : YES
FSM Encoding Algorithm             : Auto
Safe Implementation                : No
FSM Style                          : lut
RAM Extraction                     : Yes
RAM Style                          : Auto
ROM Extraction                     : Yes
Mux Style                          : Auto
Decoder Extraction                 : YES
Priority Encoder Extraction        : YES
Shift Register Extraction          : YES
Logical Shifter Extraction         : YES
XOR Collapsing                     : YES
ROM Style                          : Auto
Mux Extraction                     : YES
Resource Sharing                   : YES
Asynchronous To Synchronous        : NO
Multiplier Style                   : auto
Automatic Register Balancing       : No

---- Target Options
Add IO Buffers                     : YES
Global Maximum Fanout              : 500
Add Generic Clock Buffer(BUFG)     : 8
Register Duplication               : YES
Slice Packing                      : YES
Optimize Instantiated Primitives   : NO
Use Clock Enable                   : Yes
Use Synchronous Set                : Yes
Use Synchronous Reset              : Yes
Pack IO Registers into IOBs        : auto
Equivalent register Removal        : YES

---- General Options
Optimization Goal                  : Speed
Optimization Effort                : 1
Library Search Order               : dynamic5stage.lso
Keep Hierarchy                     : NO
RTL Output                         : Yes
Global Optimization                : AllClockNets
Read Cores                         : YES
Write Timing Constraints           : NO
Cross Clock Analysis               : NO
Hierarchy Separator                : /
Bus Delimiter                      : <>
Case Specifier                     : maintain
Slice Utilization Ratio            : 100
BRAM Utilization Ratio             : 100
Verilog 2001                       : YES
Auto BRAM Packing                  : NO
Slice Utilization Ratio Delta      : 5

=========================================================================


=========================================================================
*                          HDL Compilation                              *
=========================================================================
Compiling vhdl file "C:/Xilinx92i/sbox/dynamic5stage.vhd" in Library work.
Entity <dynamic5stage> compiled.
Entity <dynamic5stage> (Architecture <Behavioral>) compiled.

=========================================================================
*                     Design Hierarchy Analysis                         *
=========================================================================
Analyzing hierarchy for entity <dynamic5stage> in library <work> (architecture <Behavioral>).


=========================================================================
*                            HDL Analysis                               *
=========================================================================
Analyzing Entity <dynamic5stage> in library <work> (Architecture <Behavioral>).
INFO:Xst:1561 - "C:/Xilinx92i/sbox/dynamic5stage.vhd" line 278: Mux is complete : default of case is discarded
Entity <dynamic5stage> analyzed. Unit <dynamic5stage> generated.

=========================================================================
HDL Synthesis Report

Macro Statistics
# ROMs                                                 : 1
 16x4-bit ROM                                          : 1
# Registers                                            : 13
 4-bit register                                        : 12
 8-bit register                                        : 1
# Xors                                                 : 89
 1-bit xor2                                            : 56
 1-bit xor3                                            : 24
 1-bit xor4                                            : 1
 2-bit xor2                                            : 6
 4-bit xor2                                            : 2

=========================================================================

=========================================================================
*                       Advanced HDL Synthesis                          *
=========================================================================

Loading device for application Rf_Device from file '3s200.nph' in environment C:\Xilinx92i.
INFO:Xst:2506 - Unit <dynamic5stage> : In order to maximize performance and save block RAM resources, the small ROM <Mrom_GALOIS_MUL_INV> will be implemented on LUT. If you want to force its implementation on block, use option/constraint rom_style.
INFO:Xst:2261 - The FF/Latch <STAGE2_1_3> in Unit <dynamic5stage> is equivalent to the following FF/Latch, which will be removed : <STAGE2_2_1> 

=========================================================================
Advanced HDL Synthesis Report

Macro Statistics
# ROMs                                                 : 1
 16x4-bit ROM                                          : 1
# Registers                                            : 55
 Flip-Flops                                            : 55
# Xors                                                 : 89
 1-bit xor2                                            : 56
 1-bit xor3                                            : 24
 1-bit xor4                                            : 1
 2-bit xor2                                            : 6
 4-bit xor2                                            : 2

=========================================================================

=========================================================================
*                         Low Level Synthesis                           *
=========================================================================

Optimizing unit <dynamic5stage> ...

Mapping all equations...
Building and optimizing final netlist ...
Found area constraint ratio of 100 (+ 5) on block dynamic5stage, actual ratio is 3.

Final Macro Processing ...

=========================================================================
Final Register Report

Macro Statistics
# Registers                                            : 55
 Flip-Flops                                            : 55

=========================================================================

=========================================================================
*                          Partition Report                             *
=========================================================================

Partition Implementation Status
-------------------------------

  No Partitions were found in this design.

-------------------------------

=========================================================================
*                            Final Report                               *
=========================================================================
Final Results
RTL Top Level Output File Name     : dynamic5stage.ngr
Top Level Output File Name         : dynamic5stage
Output Format                      : NGC
Optimization Goal                  : Speed
Keep Hierarchy                     : NO

Design Statistics
# IOs                              : 19

Cell Usage :
# BELS                             : 114
#      LUT2                        : 22
#      LUT2_D                      : 4
#      LUT2_L                      : 1
#      LUT3                        : 14
#      LUT3_L                      : 2
#      LUT4                        : 49
#      LUT4_D                      : 3
#      LUT4_L                      : 12
#      MUXF5                       : 7
# FlipFlops/Latches                : 55
#      FDR                         : 54
#      FDRS                        : 1
# Clock Buffers                    : 1
#      BUFGP                       : 1
# IO Buffers                       : 18
#      IBUF                        : 10
#      OBUF                        : 8
=========================================================================

Device utilization summary:
---------------------------

Selected Device : 3s200pq208-5 

 Number of Slices:                      61  out of   1920     3%  
 Number of Slice Flip Flops:            55  out of   3840     1%  
 Number of 4 input LUTs:               107  out of   3840     2%  
 Number of IOs:                         19
 Number of bonded IOBs:                 19  out of    141    13%  
 Number of GCLKs:                        1  out of      8    12%  

---------------------------
Partition Resource Summary:
---------------------------

  No Partitions were found in this design.

---------------------------


=========================================================================
TIMING REPORT

NOTE: THESE TIMING NUMBERS ARE ONLY A SYNTHESIS ESTIMATE.
      FOR ACCURATE TIMING INFORMATION PLEASE REFER TO THE TRACE REPORT
      GENERATED AFTER PLACE-and-ROUTE.

Clock Information:
------------------
-----------------------------------+------------------------+-------+
Clock Signal                       | Clock buffer(FF name)  | Load  |
-----------------------------------+------------------------+-------+
SYS_CLK                            | BUFGP                  | 55    |
-----------------------------------+------------------------+-------+

Asynchronous Control Signals Information:
----------------------------------------
No asynchronous control signals found in this design

Timing Summary:
---------------
Speed Grade: -5

   Minimum period: 4.822ns (Maximum Frequency: 207.394MHz)
   Minimum input arrival time before clock: 6.639ns
   Maximum output required time after clock: 6.216ns
   Maximum combinational path delay: No path found

Timing Detail:
--------------
All values displayed in nanoseconds (ns)

=========================================================================
Timing constraint: Default period analysis for Clock 'SYS_CLK'
  Clock period: 4.822ns (frequency: 207.394MHz)
  Total number of paths / destination ports: 242 / 43
-------------------------------------------------------------------------
Delay:               4.822ns (Levels of Logic = 3)
  Source:            STAGE3_3_0 (FF)
  Destination:       STAGE4_2_3 (FF)
  Source Clock:      SYS_CLK rising
  Destination Clock: SYS_CLK rising

  Data Path: STAGE3_3_0 to STAGE4_2_3
                                Gate     Net
    Cell:in->out      fanout   Delay   Delay  Logical Name (Net Name)
    ----------------------------------------  ------------
     FDR:C->Q              4   0.626   1.074  STAGE3_3_0 (STAGE3_3_0)
     LUT4_D:I0->O          2   0.479   0.768  Mxor_GAL2_MUL_31_xor0000_xo<1>1 (GAL2_MUL_31_xor0000)
     LUT4:I3->O            1   0.479   0.740  Mxor_OUTPUT1_xor0000_Result<1>11 (N211)
     LUT4:I2->O            1   0.479   0.000  Mxor_OUTPUT1_xor0000_Result<1> (GALOIS_MUL_3<3>)
     FDR:D                     0.176          STAGE4_2_3
    ----------------------------------------
    Total                      4.822ns (2.239ns logic, 2.583ns route)
                                       (46.4% logic, 53.6% route)

=========================================================================
Timing constraint: Default OFFSET IN BEFORE for Clock 'SYS_CLK'
  Total number of paths / destination ports: 168 / 76
-------------------------------------------------------------------------
Offset:              6.639ns (Levels of Logic = 5)
  Source:            BYTE_IN<4> (PAD)
  Destination:       STAGE1_2_1 (FF)
  Destination Clock: SYS_CLK rising

  Data Path: BYTE_IN<4> to STAGE1_2_1
                                Gate     Net
    Cell:in->out      fanout   Delay   Delay  Logical Name (Net Name)
    ----------------------------------------  ------------
     IBUF:I->O             7   0.715   1.201  BYTE_IN_4_IBUF (BYTE_IN_4_IBUF)
     LUT2:I0->O            2   0.479   0.804  GALOIS_ADD_1<0>31 (GALOIS_ADD_1<0>_bdd5)
     LUT4:I2->O            1   0.479   0.976  GALOIS_ADD_1<0>11 (GALOIS_ADD_1<0>_bdd0)
     LUT3:I0->O            1   0.479   0.851  GALOIS_ADD_1<1>_SW0 (N25)
     LUT4:I1->O            1   0.479   0.000  GALOIS_ADD_1<1> (GALOIS_ADD_1<1>)
     FDR:D                     0.176          STAGE1_2_1
    ----------------------------------------
    Total                      6.639ns (2.807ns logic, 3.832ns route)
                                       (42.3% logic, 57.7% route)

=========================================================================
Timing constraint: Default OFFSET OUT AFTER for Clock 'SYS_CLK'
  Total number of paths / destination ports: 8 / 8
-------------------------------------------------------------------------
Offset:              6.216ns (Levels of Logic = 1)
  Source:            OUTPUT_LATCH_7 (FF)
  Destination:       SUB_BYTE_OUT<7> (PAD)
  Source Clock:      SYS_CLK rising

  Data Path: OUTPUT_LATCH_7 to SUB_BYTE_OUT<7>
                                Gate     Net
    Cell:in->out      fanout   Delay   Delay  Logical Name (Net Name)
    ----------------------------------------  ------------
     FDR:C->Q              1   0.626   0.681  OUTPUT_LATCH_7 (OUTPUT_LATCH_7)
     OBUF:I->O                 4.909          SUB_BYTE_OUT_7_OBUF (SUB_BYTE_OUT<7>)
    ----------------------------------------
    Total                      6.216ns (5.535ns logic, 0.681ns route)
                                       (89.0% logic, 11.0% route)

=========================================================================
CPU : 29.56 / 34.76 s | Elapsed : 29.00 / 34.00 s

--> 

Total memory usage is 205164 kilobytes

Number of errors   :    0 (   0 filtered)
Number of warnings :    0 (   0 filtered)
Number of infos    :    3 (   0 filtered)
1

There are 1 answers

0
Rune Dahl Jorgensen On

To measure the performance of your AES block, you can multiply the autotimespec value of 3.612ns from the bottom of the place and route report, with the number of pipeline stages in your system. You write that you have 5 pipeline stages currently, so the total time through the system will be 5*3.612ns = 18.060ns. If you add another pipeline stage in the hope that it will make the system faster, then the clock must be able to run at 18.060ns/6 = 3.010 ns for the added pipeline stage to improve your performance.

The tool has calculated a minimum clock period of 3.612ns = 276 MHz, but if you constrain the sys_clk to be faster than that it might be able to make it faster.