fix_eco_timing修setup和hold的问题

yuenlee

目前正在使用PT来check timing 有发现少许的setup/hold time violation

目前有在网路上找到修setup/hold time violation的办法
fix_eco_timing -methods {size_cell insert_buffer} -type hold -buffer_list
write_changes -format pt_script -output fix_hold_eco.tcl
想请问fix_hold_eco.tcl是要在ICC2的哪个阶段去soure CTS or Route?

还有也想请问前辈们有没有更好的办法来修timing violation
或是我需要调整的地方 谢谢!

smc1017

The correct stage to source the fix_hold_eco.tcl script largely depends on your project's criticality and tapeout schedule . However, in most cases, especially when you're approaching final timing closure, the script is typically sourced after routing .

        1. Remove filler cells – This step is necessary because filler cells might occupy space needed for ECO cell placement.       

        2. Source the ECO script – Run the fix_setup_hold_eco.tcl script generated by PrimeTime to apply timing fixes.       

        3. Place the ECO cells – Use the place_eco_cells command to position the newly inserted or modified cells.       

        4. Legalize placement – ​​Run legalize_placement -incremental to ensure all ECO cells are legally placed.       

        5. Route the ECO nets – Use route_eco to connect the modified or new nets introduced by the ECO script.       

        6. Run LVS checks – Finally, run check_lvs to verify that there are no open nets or shorts introduced during the ECO process.       

yuenlee

smc1017 发表于 2025-5-17 01:27
The correct stage to source the fix_hold_eco.tcl script largely depends on your project's criticalit ...

Thank you so much for your response! This has been incredibly helpful to me!

yuenlee

smc1017 发表于 2025-5-16 17:25
The correct stage to source the fix_hold_eco.tcl script largely depends on your project's criticalit ...

"I have a question I'd like to ask you:
When I use the command fix_eco_timing -type setup -methods {size_cell}, it fails. Do you know what might be causing this?"

pt_shell> fix_eco_timing -type setup -methods {size_cell}
Information: Setting timing_save_pin_arrival_and_slack to TRUE and updating timing. (PTE-076)
Information: It is recommended that the variable timing_save_pin_arrival_and_slack be set before the initial timing update for optimal performance of this command. (PTE-077)
Information: GUI is active. Stopping for performance...
To restart the GUI, type 'gui_start'.
Information: Checked out license 'PrimeTime-SI' (PT-019)
Information: Starting timing fix iteration 1 at [ Mon May 19 13:11:09 2025 ]...
Information: 3 violating endpoints located... (PTECO-022)
Information: 3 endpoints are being considered for fixing... (PTECO-027)
Information: Fixing violations...
Information: Loading library 'worst' data due to accessing lib cells not linked in the current design. (LNK-041)
Information: Loading library 'worst' data due to accessing lib cells not linked in the current design. (LNK-041)
Information: Loading library 'worst' data due to accessing lib cells not linked in the current design. (LNK-041)
Information: Loading library 'worst' data due to accessing lib cells not linked in the current design. (LNK-041)
Information: Loading library 'worst' data due to accessing lib cells not linked in the current design. (LNK-041)
Information: Loading library 'worst' data due to accessing lib cells not linked in the current design. (LNK-041)
Information: Loading library 'worst' data due to accessing lib cells not linked in the current design. (LNK-041)

Information: Starting timing fix iteration 2 at [ Mon May 19 13:11:09 2025 ]...
Information: 3 violating endpoints located... (PTECO-022)
Information: 3 endpoints are being considered for fixing... (PTECO-027)
Information: Fixing violations...
Information: Starting updating timing at [ Mon May 19 13:11:09 2025 ]...
Information: Finished updating timing at [ Mon May 19 13:11:09 2025 ]...
Information: 1 cells have been resized.

Information: Starting timing fix iteration 3 at [ Mon May 19 13:11:09 2025 ]...
Information: 3 violating endpoints located... (PTECO-022)
Information: 3 endpoints are being considered for fixing... (PTECO-027)
Information: Fixing violations...
Information: Starting updating timing at [ Mon May 19 13:11:09 2025 ]...
Information: Finished updating timing at [ Mon May 19 13:11:09 2025 ]...
Information: 2 cells have been resized.

Information: Starting timing fix iteration 4 at [ Mon May 19 13:11:09 2025 ]...
Information: 3 violating endpoints located... (PTECO-022)
Information: 3 endpoints are being considered for fixing... (PTECO-027)
Information: Fixing violations...
Information: No more fixes are available.
Information: The timing violation fixing process is complete.

Final ECO Summary:
--------------------------------------------------------
Number of size_cell commands                           3
Total number of commands                               3
Area increased by cell sizing                      18.11
Total area increased                               18.11

Fixing Summary:
--------------------------------------------------------
Total violating endpoints found                        3
Total violating endpoints fixed                        0
Total violating endpoints remaining                    3
Total percentage of violations fixed                 0.0%

Information: Elapsed time [                0 seconds ]
Information: Completed at [ Mon May 19 13:11:09 2025 ]

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