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rocket-chip/uncore/src/main/scala/directory.scala
2015-02-28 17:32:03 -08:00

44 lines
1.3 KiB
Scala

// See LICENSE for license details.
package uncore
import Chisel._
// This class encapsulates transformations on different directory information
// storage formats
abstract class DirectoryRepresentation(val width: Int) {
def pop(prev: UInt, id: UInt): UInt
def push(prev: UInt, id: UInt): UInt
def flush: UInt
def none(s: UInt): Bool
def one(s: UInt): Bool
def count(s: UInt): UInt
def next(s: UInt): UInt
def full(s: UInt): UInt
}
abstract trait HasDirectoryRepresentation {
val dir: DirectoryRepresentation
}
class NullRepresentation(nClients: Int) extends DirectoryRepresentation(1) {
def pop(prev: UInt, id: UInt) = UInt(0)
def push(prev: UInt, id: UInt) = UInt(0)
def flush = UInt(0)
def none(s: UInt) = Bool(false)
def one(s: UInt) = Bool(false)
def count(s: UInt) = UInt(nClients)
def next(s: UInt) = UInt(0)
def full(s: UInt) = SInt(-1, width = nClients).toUInt
}
class FullRepresentation(nClients: Int) extends DirectoryRepresentation(nClients) {
def pop(prev: UInt, id: UInt) = prev & ~UIntToOH(id)
def push(prev: UInt, id: UInt) = prev | UIntToOH(id)
def flush = UInt(0, width = width)
def none(s: UInt) = s === UInt(0)
def one(s: UInt) = PopCount(s) === UInt(1)
def count(s: UInt) = PopCount(s)
def next(s: UInt) = PriorityEncoder(s)
def full(s: UInt) = s
}