Fundamental new features:
* Added tile package: This package is intended to hold components re-usable across different types of tile. Will be the future location of TL2-RoCC accelerators and new diplomatic versions of intra-tile interfaces.
* Adopted [ModuleName]Params convention: Code base was very inconsistent about what to name case classes that provide parameters to modules. Settled on calling them [ModuleName]Params to distinguish them from config.Parameters and config.Config. So far applied mostly only to case classes defined within rocket and tile.
* Defined RocketTileParams: A nested case class containing case classes for all the components of a tile (L1 caches and core). Allows all such parameters to vary per-tile.
* Defined RocketCoreParams: All the parameters that can be varied per-core.
* Defined L1CacheParams: A trait defining the parameters common to L1 caches, made concrete in different derived case classes.
* Defined RocketTilesKey: A sequence of RocketTileParams, one for every tile to be created.
* Provided HeterogeneousDualCoreConfig: An example of making a heterogeneous chip with two cores, one big and one little.
* Changes to legacy code: ReplacementPolicy moved to package util. L1Metadata moved to package tile. Legacy L2 cache agent removed because it can no longer share the metadata array implementation with the L1. Legacy GroundTests on life support.
Additional changes that got rolled in along the way:
* rocket: Fix critical path through BTB for I$ index bits > pgIdxBits
* coreplex: tiles connected via :=*
* groundtest: updated to use TileParams
* tilelink: cache cork requirements are relaxed to allow more cacheless masters
A lot of utility code was just being imported willy-nilly from one
package to another. This moves the common code into util to make things
more sensible. The code moved were
* The AsyncQueue and AsyncDecoupledCrossing from junctions.
* All of the code in rocket's util.scala
* The BlackBox asynchronous reset registers from uncore.tilelink2
* The implicit definitions from uncore.util
If a device has configurable bus-width, we need a stable way of
enumerating registers. The byte offset stays unchanged.
This change also makes it possible to put an arbitrary number of RegFields
starting at some address which are then chopped up into appropriately bus-
sized registers.
Running rocket-chip through the chisel3 gsdt branch which supports stricter connection checks and uses implicit definitions to deal with "old" direction overrides, exposed a possible bug in the Scala compiler.
[error] .../src/main/scala/uncore/devices/Prci.scala:27: value asOutput is not a member of uncore.devices.PRCIInterrupts{val mtip: chisel3.core.Bool; val msip: chisel3.core.Bool}
[error] possible cause: maybe a semicolon is missing before `value asOutput'?
[error] }.asOutput
[error] ^
[error] one error found
[error] (uncore/compile:compileIncremental) Compilation failed
This change isn't strictly required for current chisel3 code, but is being submitted in anticipation of an eventual merge of the gsdt branch prior to a compiler fix.
