Critical Paths
The final two report sections show the path detail reports for the maximum (setup) and
minimum (hold) critical paths. The report only shows the most critical path for each
relationship. To see additional paths, use the report_timing Tcl
command (see report_timing Command). A typical path report
consists of the following sections:
- Header—Specifies the launch and capture clock domains.
- Path summary—Lists the start and end points of a given path. It also shows the launch and capture clock information as well as the associatged clock edges, the slack, and a summary of the arrival and required time calculations.
- Launch clock path—The path the clock signals takes.
- Data path—The path the data signal takes
- Capture clock path—The path the capture clock takes.
The following example shows a snippet of the report for Oclk.
Max Critical Path, Detail Report
################################################################################
Path Detail Report (Oclk vs Oclk)
################################################################################
++++ Path 1 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Path Begin : Oled[2]~FF|CLK
Path End : Oled[3]~FF|D
Launch Clock : Oclk (RISE)
Capture Clock : Oclk (RISE)
Slack : 99999.408 (required time - arrival time)
Delay : 0.358
Logic Level : 1
Non-global nets on path : 1
Global nets on path : 0
Launch Clock Path Delay : 2.342
+ Clock To Q + Data Path Delay : 0.474
--------------------------------------
End-of-path arrival time : 2.816
Constraint : 99999.992
+ Capture Clock Path Delay : 2.342
- Clock Uncertainty : 0.110
-------------------------------------------
End-of-path required time : 100002.224
Launch Clock Path
name model name delay (ns) cumulative delay (ns) pins on net location
========================================================================================
Oclk inpad 0.000 0.000 0 (334,318)
Oclk inpad 0.110 0.110 6 (334,318)
Oclk net 2.232 2.342 6 (334,318)
Routing elements:
Manhattan distance of X:214, Y:314
Oled[2]~FF|CLK ff 0.000 2.342 6 (120,4)
Data Path
name model name delay (ns) cumulative delay (ns) pins on net location
=======================================================================================
Oled[2]~FF|Q ff 0.113 0.113 4 (120,4)
Oled[2] net 0.304 0.417 4 (120,4)
Routing elements:
Manhattan distance of X:0, Y:1
LUT__77|in[2] lut 0.054 0.471 4 (120,5)
LUT__77|out lut 0.000 0.471 2 (120,5)
Oled[3]~FF|D ff 0.003 0.474 2 (120,5)
Capture Clock Path
name model name delay (ns) cumulative delay (ns) pins on net location
========================================================================================
Oclk inpad 0.000 0.000 0 (334,318)
Oclk inpad 0.110 0.110 6 (334,318)
Oclk net 2.232 2.342 6 (334,318)
Routing elements:
Manhattan distance of X:214, Y:313
Oled[3]~FF|CLK ff 0.000 2.342 6 (120,5)