The sky130hd platform uses a default layer resources reduction of 20%. For designs such aes, this reduction percentage seems too small, causing DRT to run many more iterations to complete the routing when compared to using a larger reduction.
In other words, the aes design benefits from a larger reduction value because it reduces the detailed router's number of iterations. We are not doing a good job in routability during GRT and need more reduction to compensate.
Investigate why the global routing result with 20% reduction produces so many more iterations in DRT.
Expected Behavior
GRT should produce a global routing result with good routability for DRT even when using smaller reduction percentages.
Environment
Not applied.
To Reproduce
In ORFS, modify the file flow/designs/sky130hd/aes/fastroute.tcl in its first line to apply 0.2 of reduction, instead of 0.4.
Subject
[Stage]: Global Router.
Describe the bug
The sky130hd platform uses a default layer resources reduction of 20%. For designs such aes, this reduction percentage seems too small, causing DRT to run many more iterations to complete the routing when compared to using a larger reduction.
In other words, the aes design benefits from a larger reduction value because it reduces the detailed router's number of iterations. We are not doing a good job in routability during GRT and need more reduction to compensate.
Investigate why the global routing result with 20% reduction produces so many more iterations in DRT.
Expected Behavior
GRT should produce a global routing result with good routability for DRT even when using smaller reduction percentages.
Environment
To Reproduce
In ORFS, modify the file
flow/designs/sky130hd/aes/fastroute.tclin its first line to apply 0.2 of reduction, instead of 0.4.Relevant log output
No response
Screenshots
No response
Additional Context
No response