[ERROR PDN-0351] Ring shape falls outside the die bounds.

[oharboe]

Describe the bug

untar and run pdn_sdq_17x64_asap7_mocked_2025-01-30_15-10.tar.gz

$ ./run-me-sdq_17x64-asap7-mocked.sh 
OpenROAD v2.0-18694-g401a7bb30 
Features included (+) or not (-): +GPU +GUI +Python
This program is licensed under the BSD-3 license. See the LICENSE file for details.
Components of this program may be licensed under more restrictive licenses which must be honored.
[ERROR PDN-0351] Ring shape falls outside the die bounds.
Error: BLOCK_grid_strategy.tcl, 23 PDN-0351
openroad> 

Expected Behavior

No error.

Environment

OpenROAD v2.0-18694-g401a7bb30

Tried all the way back to OpenROAD v2.0-16961-g6b3508ac6, same error.

To Reproduce

See above

Relevant log output

Screenshots

No response

Additional Context

No response

[oharboe]

@jeffng-or FYI fails in The-OpenROAD-Project/megaboom#229

[gadfort]

@oharboe this is intentional now (#6445)
You need to fix your power grid or explicitly allow the rings to go outside the die (I would recommend fixing the grid instead of allowing it outside the die).

[oharboe]

But I am using a PDN from ORFS platforms/asap7 folder and this .tcl file is used in a ton of places and this is the first place I have seen it fail. I am not familiar with any design specific knobs that I can tweak.

Could you have a look and give some more specific instructions for non PDN expert...?

[gadfort]

I think you can just make the width smaller, spacing smaller, or core offset smaller to resolve this.
The issue needs to be fixed in ORFS.

[oharboe]

I think you can just make the width smaller, spacing smaller, or core offset smaller to resolve this.
The issue needs to be fixed in ORFS.

Silly question: which ORFS variables?

[gadfort]

I think it's in a file in the platform enablement, no variables involved.

[oharboe]

@maliberty @jeffng-or I guess you are way ahead of me on this :-)

[maliberty]

Either the pdn config can be changed or the core-to-die spacing needs to be large enough to accommodate the rings. I think it easiest is to increase the core-to-die spacing through CORE_MARGIN or CORE_AREA depending on how you setup the floorplan.

[oharboe]

Can the error message give more specific actionable advice: increase by X and Y?

[maliberty]

Can the error message give more specific actionable advice: increase by X and Y?

@gadfort ? Of course there are multiple ways to fix it so it would just be one possibiilty.

[gadfort]

@maliberty pdn could output the amount by which the ring extends outside of the die?

[maliberty]

Let's have some text to suggest how that value might be used. Some like

PDN rings do not fit inside the die area by <val> um in X and <val2> um in Y.  Either reduce the ring area or increase the core to die spacing to accommodate.  Use -allow_out_of_die if this is intentional.

[oharboe]

I modified bazel-orfs mocked area to scale the die area, but keep the die to core distance unchanged: The-OpenROAD-Project/bazel-orfs#276

[oharboe]

Closing as duplicate/known problem.

Improved actionable and specific error messages are great usability improvements, suggestion from @maliberty looks good.