What is the use of Punch Through in AbstarctConfig Scala files.

[cygwin24]

Background Work

• Yes, I searched the mailing list
• Yes, I searched prior issues
• Yes, I searched the documentation

Chipyard Version and Hash

Release: 1.5.0
Hash: a6a6a6

OS Setup

Ex: Output of uname -a + lsb_release -a + printenv + conda list

Other Setup

Ex: Prior steps taken / Documentation Followed / etc...

Current Behavior

Hi.
I am seeing the Punch Through in the AbstractConfig.scala file. But couldn't understand what is the use of PunchThrough here.

Expected Behavior

.

Other Information

No response

[jerryz123]

For these IO port types, we don't actually expect people will tape out chips where these ports are exposed as top-level pins of the Chip (and therefore, need IOCells). These I/Os exist only for simulation purposes, and so can be punched directly through the ChipTop to the TestHarness, without needing to instantiate IO cells.