[ERROR RSZ-0074] failed to build tree

[laurentc2]

Hi,
Using the OpenROAD-flow-scripts with a commercial process XP018, I got the following error :

[ERROR RSZ-0074] failed to build tree from gloubal routes: found route to 2 pins, expected 3
Error: global_route.tcl, 120 RSZ-0074
Command exited with non-zero status 1

What could be the origin of this error ? What can I try to debug it ?
Thank you, Best regards,
Laurent

[maliberty]

@eder-matheus thoughts?

[eder-matheus]

It might be a problem with layer assignment. This error message doesn't give enough information, but I guess global router is not creating vias to access one of the pins. We can update this error message with more details about the net and the pins that are failing.

[dnltz]

I just got the same error with the IHP PDK.

[ERROR RSZ-0074] failed to build tree from gloubal routes: found route to 1 pins, expected 0
Error: global_route.tcl, 120 RSZ-0074
Command exited with non-zero status 1

[maliberty]

Can you provide a test case?

[dnltz]

https://limewire.com/d/GzyXq#SWDOxEDFCm

[dnltz]

@maliberty is this link working? I just used the first "upload file" website :D

[dnltz]

So, in my case I added three IO cells as placeholders "for future use". I just picked input cells and the floating pad to chip wire got removed. The ODB generated after CTS also showed no nets connected to the p2c pin.

I changed these placeholders to output cells with tielo cells and it's working now :)

[DEBUG RSZ-repair_net] repair net io_forFutureUse_2_PAD
[DEBUG RSZ-repair_net] pin io_forFutureUse_2_PAD drvr grid (3150 3150) layer 2
[ERROR RSZ-0074] failed to build tree from gloubal routes: found route to 1 pins, expected 0
Error: global_route.tcl, 123 RSZ-0074
Command exited with non-zero status 1

[laurentc2]

Hi,

Trying to find the guilty step of :
[ERROR RSZ-0074] failed to build tree from gloubal routes: found route to 1 pins, expected 0
Error: global_route.tcl, 120 RSZ-0074
Command exited with non-zero status 1

I found out that if I remove the repair_design_helper step in the global_route.tcl , it solved the issue ... at the price of a repair not done.

By the way, to finish the GDS, Matthias K. helped me to change -zz option to -b to avoid a crash of KLayout.

BRgds,
Laurent

[dnltz]

Hey @laurentc2, you can enable debug output for the Gate Resizer. I just enabled it right before the repair_design_helper. Can you please post the last ~20 lines here?

--- a/flow/scripts/global_route.tcl
+++ b/flow/scripts/global_route.tcl
@@ -53,6 +53,8 @@ proc global_route_helper { } {
       report_metrics 5 "global route pre repair design"
     }
 
+    set_debug_level RSZ repair_net 2
+
     # Repair design using global route parasitics
     repair_design_helper
     if { $::env(DETAILED_METRICS) } {