Doing this in Chisel leads to non-determinism due to shitty
Verilog ordering semantis. Using an '=' ensures that all of
the clock posedges fire before concurrent register updates.
See "Gotcha 29: Sequential logic that requires blocking assignments"
in "Verilog and SystemVerilog Gotchas" by Stuart Sutherland, Don Mills.
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
If the other clock domain is much faster than ours, it's reset
might be shorter than a single cycle in our domain. In that case,
we need to catch the reset and extend it.
This reverts commit a84a961a39.
The changes to RegisterCrossing.scala were unneeded after application of this branch.
The name changes made to the AsyncQueue.scala are reapplied at the end of this branch.
Lint-[PCTIO-L] Ports coerced to inout
rocket-chip/vsim/generated-src/unittest.UncoreUnitTestConfig.v, 127524
"io_deq_0_valid"
Port "io_deq_0_valid" declared as output in module "PositionalMultiQueue_16"
may need to be inout. Coercing to inout.
* Suggest sane names for common objects frequently instantiated with factory methods
* Suggest names for common primitives using more Scala-esque Options
