Stats

  • Locked Locked
  • Replies 6
  • Subscribers 91
  • Views 17868
  • Members are here 0
This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

report_timing issue

meds7

Dear all,


I am using multimode analysis views for creation of multi corner timing info in my .sdf file.

After setting the analysis view and trying to report timing with the 'report_timing' command in encounter I see that no delays are used for my clock tree. It is only the clock tree timing info which is missing in the timing reports. All other delays are present.

Does anybody know what I am doing wrong?

regard

Henk

Parents
  • Hi Kari,

    Maybe I am using MMMC wrong.

    My flow uses the default_mode_setup and default_mode_hold constraints which are created by the tool (of course based on my sdc constraints).

    I just wanted to generate one additional corner (typical 25 degree corner) to the results in my generated sdf file. Therefore I added one additonal rc corner, a delay corner and a typical constraint mode in order to create the typical new analysis view for 25 degrees.

    Then I generate the layout with clocktree and at the end the timing reports are correctly generated as a result of the optDesign command I believe.

    At that point I can see all correct timing info in the reports including delays inside the clock tree.

    At the end of my script where I want to generate the sdf file I set my analysis views again with this command:

    set_analysis_view -setup {default_view_hold typical_view default_view_setup} -hold {default_view_hold typical_view default_view_setup}

    after which I generate the sdf with write_sdf

    However, from that point when I type report_timing from the prompt I get a report which does not involve the clocktree delays anymore.

    Interactive constraint mode does not seem to be possible at that poinr because I am using the default_view_setup and the default_view_hold.

    Therefore, I still don't understand now where I went wrong...

    regards
Reply
  • Hi Kari,

    Maybe I am using MMMC wrong.

    My flow uses the default_mode_setup and default_mode_hold constraints which are created by the tool (of course based on my sdc constraints).

    I just wanted to generate one additional corner (typical 25 degree corner) to the results in my generated sdf file. Therefore I added one additonal rc corner, a delay corner and a typical constraint mode in order to create the typical new analysis view for 25 degrees.

    Then I generate the layout with clocktree and at the end the timing reports are correctly generated as a result of the optDesign command I believe.

    At that point I can see all correct timing info in the reports including delays inside the clock tree.

    At the end of my script where I want to generate the sdf file I set my analysis views again with this command:

    set_analysis_view -setup {default_view_hold typical_view default_view_setup} -hold {default_view_hold typical_view default_view_setup}

    after which I generate the sdf with write_sdf

    However, from that point when I type report_timing from the prompt I get a report which does not involve the clocktree delays anymore.

    Interactive constraint mode does not seem to be possible at that poinr because I am using the default_view_setup and the default_view_hold.

    Therefore, I still don't understand now where I went wrong...

    regards
Children
No Data

Community Guidelines

The Cadence Design Communities support Cadence users and technologists interacting to exchange ideas, news, technical information, and best practices to solve problems and get the most from Cadence technology. The community is open to everyone, and to provide the most value, we require participants to follow our Community Guidelines that facilitate a quality exchange of ideas and information. By accessing, contributing, using or downloading any materials from the site, you agree to be bound by the full Community Guidelines.