Use "tile" instead of "core" to assign freq's in WithTileFrequency config. fragment

[abejgonzalez]

Related issue:

Type of change: bug fix

Impact: other

Release Notes
Fixes an issue where WithTileFrequency wouldn't modify the frequency of all tiles since clock names are based on the TileParams name (which defaults to tile and boom_tile for Rocket/BOOM respectively).

Tested with 2 configs:

1. MulticlockRocketConfig:
   

2. DoubleRocketAndBoomConfig (custom config that only used WithTileFrequency(600) - no other freq's changed):
   

[jerryz123]

I remember this was done because it defaults naming everything to core_{hartid}, done here: https://github.com/chipsalliance/rocket-chip/blob/8f9149faf01fec9725d08c31c9c0bb5341f5e999/src/main/scala/subsystem/HasTiles.scala#L251

Was there a change somewhere that changed the naming to tile?

[abejgonzalez]

I saw that... The getOrElse is getting what <Rocket/Boom>TileParams gives: https://github.com/chipsalliance/rocket-chip/blob/8f9149faf01fec9725d08c31c9c0bb5341f5e999/src/main/scala/tile/RocketTile.scala#L25. I'm not sure how this worked before...

[jerryz123]

Approved, but @davidbiancolin should take a look as well

[davidbiancolin]

It was named core before (yay strings). This LGTM.