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Default CTS arguments don't give good skew results

Open oharboe opened this issue 1 year ago • 4 comments

Description

Expected:

image

Actual:

image

To reproduce: untar cts.tar.gz

./run-me-mock-array-asap7-base.sh
. vars-mock-array-asap7-base.sh
ODB_FILE=results/asap7/mock-array/base/4_1_cts.odb openroad -gui scripts/gui.tcl

Suggested Solution

CTS should automatically pick good defaults

Additional Context

No response

oharboe avatar Mar 08 '24 17:03 oharboe

It seems that the timing repair step is degrading the clock skew. Some of timing repair can be pulled into CTS to mitigate this issue. @oharboe, what's the needed timeline for this enhancement?

precisionmoon avatar Mar 08 '24 18:03 precisionmoon

It seems that the timing repair step is degrading the clock skew. Some of timing repair can be pulled into CTS to mitigate this issue. @oharboe, what's the needed timeline for this enhancement?

I would prioritize orderly progression of development over particular features.

oharboe avatar Mar 08 '24 18:03 oharboe

I would guess it is repair_clock_nets rather than repair_timing that is the problem (the later shouldn't touch the clock tree).

maliberty avatar Mar 08 '24 22:03 maliberty

I would guess it is repair_clock_nets rather than repair_timing that is the problem (the later shouldn't touch the clock tree).

Correct.

precisionmoon avatar Mar 08 '24 23:03 precisionmoon