diff options
| author | Henry Cook | 2015-08-04 10:47:25 -0700 |
|---|---|---|
| committer | Andrew Waterman | 2015-08-05 16:35:40 -0700 |
| commit | 481fb882619265c475a962ee6b664165a79cbf1e (patch) | |
| tree | 73b4b9986f5b604bf46c3ae8e6facafd36855693 /src/main/scala/Chisel/utils.scala | |
| parent | 772b3c67e415318c8dca588e1ea553db9f4b8f40 (diff) | |
normalize file capitalization
Diffstat (limited to 'src/main/scala/Chisel/utils.scala')
| -rw-r--r-- | src/main/scala/Chisel/utils.scala | 567 |
1 files changed, 0 insertions, 567 deletions
diff --git a/src/main/scala/Chisel/utils.scala b/src/main/scala/Chisel/utils.scala deleted file mode 100644 index 5756fee0..00000000 --- a/src/main/scala/Chisel/utils.scala +++ /dev/null @@ -1,567 +0,0 @@ -package Chisel -import Builder._ -import scala.math._ -import scala.language.reflectiveCalls -import scala.language.experimental.macros -import scala.reflect.runtime.universe._ -import scala.reflect.macros.blackbox._ - -object log2Up -{ - def apply(in: Int): Int = if(in == 1) 1 else ceil(log(in)/log(2)).toInt -} - -object log2Ceil -{ - def apply(in: Int): Int = ceil(log(in)/log(2)).toInt -} - - -object log2Down -{ - def apply(x : Int): Int = if (x == 1) 1 else floor(log(x)/log(2.0)).toInt -} - -object log2Floor -{ - def apply(x : Int): Int = floor(log(x)/log(2.0)).toInt -} - - -object isPow2 -{ - def apply(in: Int): Boolean = in > 0 && ((in & (in-1)) == 0) -} - -object FillInterleaved -{ - def apply(n: Int, in: UInt): UInt = apply(n, in.toBools) - def apply(n: Int, in: Seq[Bool]): UInt = Vec(in.map(Fill(n, _))).toBits -} - -/** Returns the number of bits set (i.e value is 1) in the input signal. - */ -object PopCount -{ - def apply(in: Iterable[Bool]): UInt = { - if (in.size == 0) { - UInt(0) - } else if (in.size == 1) { - in.head - } else { - apply(in.slice(0, in.size/2)) + Cat(UInt(0), apply(in.slice(in.size/2, in.size))) - } - } - def apply(in: Bits): UInt = apply((0 until in.getWidth).map(in(_))) -} - -object RegNext { - - def apply[T <: Data](next: T): T = Reg[T](next, next, null.asInstanceOf[T]) - - def apply[T <: Data](next: T, init: T): T = Reg[T](next, next, init) - -} - -object RegInit { - - def apply[T <: Data](init: T): T = Reg[T](init, null.asInstanceOf[T], init) - -} - -object RegEnable -{ - def apply[T <: Data](updateData: T, enable: Bool) = { - val r = Reg(updateData) - when (enable) { r := updateData } - r - } - def apply[T <: Data](updateData: T, resetData: T, enable: Bool) = { - val r = RegInit(resetData) - when (enable) { r := updateData } - r - } -} - -/** Builds a Mux tree out of the input signal vector using a one hot encoded - select signal. Returns the output of the Mux tree. - */ -object Mux1H -{ - def apply[T <: Data](sel: Seq[Bool], in: Seq[T]): T = - apply(sel zip in) - def apply[T <: Data](in: Iterable[(Bool, T)]): T = { - if (in.tail.isEmpty) in.head._2 - else { - val masked = in map {case (s, i) => Mux(s, i.toBits, Bits(0))} - val width = in.map(_._2.width).reduce(_ max _) - in.head._2.cloneTypeWidth(width).fromBits(masked.reduceLeft(_|_)) - } - } - def apply[T <: Data](sel: UInt, in: Seq[T]): T = - apply((0 until in.size).map(sel(_)), in) - def apply(sel: UInt, in: UInt): Bool = (sel & in).orR -} - -/** Builds a Mux tree under the assumption that multiple select signals - can be enabled. Priority is given to the first select signal. - - Returns the output of the Mux tree. - */ -object PriorityMux -{ - def apply[T <: Bits](in: Seq[(Bool, T)]): T = { - if (in.size == 1) { - in.head._2 - } else { - Mux(in.head._1, in.head._2, apply(in.tail)) - } - } - def apply[T <: Bits](sel: Seq[Bool], in: Seq[T]): T = apply(sel zip in) - def apply[T <: Bits](sel: Bits, in: Seq[T]): T = apply((0 until in.size).map(sel(_)), in) -} - -object unless { - def apply(c: Bool)(block: => Unit) { - when (!c) { block } - } -} - -class SwitchContext[T <: Bits](cond: T) { - def is(v: Iterable[T])(block: => Unit) { - if (!v.isEmpty) when (v.map(_.asUInt === cond.asUInt).reduce(_||_)) { block } - } - def is(v: T)(block: => Unit) { is(Seq(v))(block) } - def is(v: T, vr: T*)(block: => Unit) { is(v :: vr.toList)(block) } -} - -object is { // Begin deprecation of non-type-parameterized is statements. - def apply(v: Iterable[Bits])(block: => Unit) { ChiselError.error("The 'is' keyword may not be used outside of a switch.") } - def apply(v: Bits)(block: => Unit) { ChiselError.error("The 'is' keyword may not be used outside of a switch.") } - def apply(v: Bits, vr: Bits*)(block: => Unit) { ChiselError.error("The 'is' keyword may not be used outside of a switch.") } -} - -object switch { - def apply[T <: Bits](cond: T)(x: => Unit): Unit = macro impl - def impl(c: Context)(cond: c.Tree)(x: c.Tree) = { import c.universe._ - val sc = c.universe.internal.reificationSupport.freshTermName("sc") - def extractIsStatement(tree: Tree): List[c.universe.Tree] = tree match { - case q"Chisel.is.apply( ..$params )( ..$body )" => List(q"$sc.is( ..$params )( ..$body )") - case b => throw new Exception(s"Cannot include blocks that do not begin with is() in switch.") - } - val q"..$body" = x - val ises = body.flatMap(extractIsStatement(_)) - q"""{ val $sc = new SwitchContext($cond); ..$ises }""" - } -} - -object MuxLookup { - def apply[S <: UInt, T <: Bits] (key: S, default: T, mapping: Seq[(S, T)]): T = { - var res = default; - for ((k, v) <- mapping.reverse) - res = Mux(k === key, v, res); - res - } - -} - -object Fill { - def apply(n: Int, y: UInt): UInt = { - n match { - case 0 => UInt(width=0) - case 1 => y - case x if n > 1 => - val p2 = Array.ofDim[UInt](log2Up(n+1)) - p2(0) = y - for (i <- 1 until p2.length) - p2(i) = Cat(p2(i-1), p2(i-1)) - Cat((0 until log2Up(x+1)).filter(i => (x & (1 << i)) != 0).map(p2(_))) - case _ => throw new IllegalArgumentException(s"n (=$n) must be nonnegative integer.") - } - } - def apply(n: Int, x: Bool): UInt = - if (n > 1) UInt(0,n) - x - else apply(n, x: UInt) -} - -object MuxCase { - def apply[T <: Bits] (default: T, mapping: Seq[(Bool, T)]): T = { - var res = default; - for ((t, v) <- mapping.reverse){ - res = Mux(t, v, res); - } - res - } -} - -object ListLookup { - def apply[T <: Data](addr: UInt, default: List[T], mapping: Array[(BitPat, List[T])]): List[T] = { - val map = mapping.map(m => (m._1 === addr, m._2)) - default.zipWithIndex map { case (d, i) => - map.foldRight(d)((m, n) => Mux(m._1, m._2(i), n)) - } - } -} - -object Lookup { - def apply[T <: Bits](addr: UInt, default: T, mapping: Seq[(BitPat, T)]): T = - ListLookup(addr, List(default), mapping.map(m => (m._1, List(m._2))).toArray).head -} - -/** Litte/big bit endian convertion: reverse the order of the bits in a UInt. -*/ -object Reverse -{ - private def doit(in: UInt, length: Int): UInt = { - if (length == 1) { - in - } else if (isPow2(length) && length >= 8 && length <= 64) { - // This esoterica improves simulation performance - var res = in - var shift = length >> 1 - var mask = UInt((BigInt(1) << length) - 1, length) - do { - mask = mask ^ (mask(length-shift-1,0) << shift) - res = ((res >> shift) & mask) | ((res(length-shift-1,0) << shift) & ~mask) - shift = shift >> 1 - } while (shift > 0) - res - } else { - val half = (1 << log2Up(length))/2 - Cat(doit(in(half-1,0), half), doit(in(length-1,half), length-half)) - } - } - def apply(in: UInt): UInt = doit(in, in.getWidth) -} - -/** Returns the n-cycle delayed version of the input signal. - */ -object ShiftRegister -{ - def apply[T <: Data](in: T, n: Int, en: Bool = Bool(true)): T = - { - // The order of tests reflects the expected use cases. - if (n == 1) { - RegEnable(in, en) - } else if (n != 0) { - RegNext(apply(in, n-1, en)) - } else { - in - } - } -} - -/** Returns the one hot encoding of the input UInt. - */ -object UIntToOH -{ - def apply(in: UInt, width: Int = -1): UInt = - if (width == -1) UInt(1) << in - else (UInt(1) << in(log2Up(width)-1,0))(width-1,0) -} - -class Counter(val n: Int) { - val value = if (n == 1) UInt(0) else Reg(init=UInt(0, log2Up(n))) - def inc(): Bool = { - if (n == 1) Bool(true) - else { - val wrap = value === UInt(n-1) - value := Mux(Bool(!isPow2(n)) && wrap, UInt(0), value + UInt(1)) - wrap - } - } -} - -object Counter -{ - def apply(n: Int): Counter = new Counter(n) - def apply(cond: Bool, n: Int): (UInt, Bool) = { - val c = new Counter(n) - var wrap: Bool = null - when (cond) { wrap = c.inc() } - (c.value, cond && wrap) - } -} - -class ValidIO[+T <: Data](gen2: T) extends Bundle -{ - val valid = Bool(OUTPUT) - val bits = gen2.cloneType.asOutput - def fire(dummy: Int = 0): Bool = valid - override def cloneType: this.type = new ValidIO(gen2).asInstanceOf[this.type] -} - -/** Adds a valid protocol to any interface. The standard used is - that the consumer uses the flipped interface. -*/ -object Valid { - def apply[T <: Data](gen: T): ValidIO[T] = new ValidIO(gen) -} - -class DecoupledIO[+T <: Data](gen: T) extends Bundle -{ - val ready = Bool(INPUT) - val valid = Bool(OUTPUT) - val bits = gen.cloneType.asOutput - def fire(dummy: Int = 0): Bool = ready && valid - override def cloneType: this.type = new DecoupledIO(gen).asInstanceOf[this.type] -} - -/** Adds a ready-valid handshaking protocol to any interface. - The standard used is that the consumer uses the flipped - interface. - */ -object Decoupled { - def apply[T <: Data](gen: T): DecoupledIO[T] = new DecoupledIO(gen) -} - -class EnqIO[T <: Data](gen: T) extends DecoupledIO(gen) -{ - def enq(dat: T): T = { valid := Bool(true); bits := dat; dat } - valid := Bool(false) - for (io <- bits.flatten) - io := UInt(0) - override def cloneType: this.type = { new EnqIO(gen).asInstanceOf[this.type]; } -} - -class DeqIO[T <: Data](gen: T) extends DecoupledIO(gen) -{ - flip() - ready := Bool(false) - def deq(b: Boolean = false): T = { ready := Bool(true); bits } - override def cloneType: this.type = { new DeqIO(gen).asInstanceOf[this.type]; } -} - - -class DecoupledIOC[+T <: Data](gen: T) extends Bundle -{ - val ready = Bool(INPUT) - val valid = Bool(OUTPUT) - val bits = gen.cloneType.asOutput -} - -class QueueIO[T <: Data](gen: T, entries: Int) extends Bundle -{ - val enq = Decoupled(gen.cloneType).flip - val deq = Decoupled(gen.cloneType) - val count = UInt(OUTPUT, log2Up(entries + 1)) -} - -class Queue[T <: Data](gen: T, val entries: Int, pipe: Boolean = false, flow: Boolean = false, _reset: Bool = null) extends Module(_reset=_reset) -{ - val io = new QueueIO(gen, entries) - - val ram = Mem(gen, entries) - val enq_ptr = Counter(entries) - val deq_ptr = Counter(entries) - val maybe_full = Reg(init=Bool(false)) - - val ptr_match = enq_ptr.value === deq_ptr.value - val empty = ptr_match && !maybe_full - val full = ptr_match && maybe_full - val maybe_flow = Bool(flow) && empty - val do_flow = maybe_flow && io.deq.ready - - val do_enq = io.enq.ready && io.enq.valid && !do_flow - val do_deq = io.deq.ready && io.deq.valid && !do_flow - when (do_enq) { - ram(enq_ptr.value) := io.enq.bits - enq_ptr.inc() - } - when (do_deq) { - deq_ptr.inc() - } - when (do_enq != do_deq) { - maybe_full := do_enq - } - - io.deq.valid := !empty || Bool(flow) && io.enq.valid - io.enq.ready := !full || Bool(pipe) && io.deq.ready - io.deq.bits := Mux(maybe_flow, io.enq.bits, ram(deq_ptr.value)) - - val ptr_diff = enq_ptr.value - deq_ptr.value - if (isPow2(entries)) { - io.count := Cat(maybe_full && ptr_match, ptr_diff) - } else { - io.count := Mux(ptr_match, Mux(maybe_full, UInt(entries), UInt(0)), Mux(deq_ptr.value > enq_ptr.value, UInt(entries) + ptr_diff, ptr_diff)) - } -} - -/** Generic hardware queue. Required parameter entries controls - the depth of the queues. The width of the queue is determined - from the inputs. - - Example usage: - val q = new Queue(UInt(), 16) - q.io.enq <> producer.io.out - consumer.io.in <> q.io.deq - */ -object Queue -{ - def apply[T <: Data](enq: DecoupledIO[T], entries: Int = 2, pipe: Boolean = false): DecoupledIO[T] = { - val q = Module(new Queue(enq.bits.cloneType, entries, pipe)) - q.io.enq.valid := enq.valid // not using <> so that override is allowed - q.io.enq.bits := enq.bits - enq.ready := q.io.enq.ready - q.io.deq - } -} - -object PriorityEncoderOH -{ - private def encode(in: Seq[Bool]): UInt = { - val outs = Vec.tabulate(in.size)(i => UInt(BigInt(1) << i, in.size)) - PriorityMux(in :+ Bool(true), outs :+ UInt(0, in.size)) - } - def apply(in: Seq[Bool]): Vec[Bool] = { - val enc = encode(in) - Vec.tabulate(in.size)(enc(_)) - } - def apply(in: Bits): UInt = encode((0 until in.getWidth).map(i => in(i))) -} - -class ArbiterIO[T <: Data](gen: T, n: Int) extends Bundle { - val in = Vec(Decoupled(gen), n).flip - val out = Decoupled(gen) - val chosen = UInt(OUTPUT, log2Up(n)) -} - -object ArbiterCtrl -{ - def apply(request: Seq[Bool]): Seq[Bool] = { - Bool(true) +: (1 until request.length).map(i => !request.slice(0, i).foldLeft(Bool(false))(_ || _)) - } -} - -abstract class LockingArbiterLike[T <: Data](gen: T, n: Int, count: Int, needsLock: Option[T => Bool] = None) extends Module { - require(isPow2(count)) - def grant: Seq[Bool] - val io = new ArbiterIO(gen, n) - val locked = if(count > 1) Reg(init=Bool(false)) else Bool(false) - val lockIdx = if(count > 1) Reg(init=UInt(n-1)) else UInt(n-1) - val chosen = Wire(UInt(width = log2Up(n))) - - io.out.valid := io.in(chosen).valid - io.out.bits := io.in(chosen).bits - io.chosen := chosen - - io.in(chosen).ready := Bool(false) // XXX FIRRTL workaround - for ((g, i) <- grant.zipWithIndex) - io.in(i).ready := Mux(locked, lockIdx === UInt(i), g) && io.out.ready - - if(count > 1){ - val cnt = Reg(init=UInt(0, width = log2Up(count))) - val cnt_next = cnt + UInt(1) - when(io.out.fire()) { - when(needsLock.map(_(io.out.bits)).getOrElse(Bool(true))) { - cnt := cnt_next - when(!locked) { - locked := Bool(true) - lockIdx := Vec(io.in.map{ in => in.fire()}).indexWhere{i: Bool => i} - } - } - when(cnt_next === UInt(0)) { - locked := Bool(false) - } - } - } -} - -class LockingRRArbiter[T <: Data](gen: T, n: Int, count: Int, needsLock: Option[T => Bool] = None) extends LockingArbiterLike[T](gen, n, count, needsLock) { - lazy val last_grant = Reg(init=UInt(0, log2Up(n))) - override def grant: Seq[Bool] = { - val ctrl = ArbiterCtrl((0 until n).map(i => io.in(i).valid && UInt(i) > last_grant) ++ io.in.map(_.valid)) - (0 until n).map(i => ctrl(i) && UInt(i) > last_grant || ctrl(i + n)) - } - - var choose = UInt(n-1) - for (i <- n-2 to 0 by -1) - choose = Mux(io.in(i).valid, UInt(i), choose) - for (i <- n-1 to 1 by -1) - choose = Mux(io.in(i).valid && UInt(i) > last_grant, UInt(i), choose) - chosen := Mux(locked, lockIdx, choose) - - when (io.out.fire()) { last_grant := chosen } -} - -class LockingArbiter[T <: Data](gen: T, n: Int, count: Int, needsLock: Option[T => Bool] = None) extends LockingArbiterLike[T](gen, n, count, needsLock) { - def grant: Seq[Bool] = ArbiterCtrl(io.in.map(_.valid)) - - var choose = UInt(n-1) - for (i <- n-2 to 0 by -1) { - choose = Mux(io.in(i).valid, UInt(i), choose) - } - chosen := Mux(locked, lockIdx, choose) -} - -/** Hardware module that is used to sequence n producers into 1 consumer. - Producers are chosen in round robin order. - - Example usage: - val arb = new RRArbiter(2, UInt()) - arb.io.in(0) <> producer0.io.out - arb.io.in(1) <> producer1.io.out - consumer.io.in <> arb.io.out - */ -class RRArbiter[T <: Data](gen:T, n: Int) extends LockingRRArbiter[T](gen, n, 1) - -/** Hardware module that is used to sequence n producers into 1 consumer. - Priority is given to lower producer - - Example usage: - val arb = Module(new Arbiter(2, UInt())) - arb.io.in(0) <> producer0.io.out - arb.io.in(1) <> producer1.io.out - consumer.io.in <> arb.io.out - */ -class Arbiter[T <: Data](gen: T, n: Int) extends LockingArbiter[T](gen, n, 1) - -/** linear feedback shift register - */ -object LFSR16 -{ - def apply(increment: Bool = Bool(true)): UInt = - { - val width = 16 - val lfsr = Reg(init=UInt(1, width)) - when (increment) { lfsr := Cat(lfsr(0)^lfsr(2)^lfsr(3)^lfsr(5), lfsr(width-1,1)) } - lfsr - } -} - -/** A hardware module that delays data coming down the pipeline - by the number of cycles set by the latency parameter. Functionality - is similar to ShiftRegister but this exposes a Pipe interface. - - Example usage: - val pipe = new Pipe(UInt()) - pipe.io.enq <> produce.io.out - consumer.io.in <> pipe.io.deq - */ -object Pipe -{ - def apply[T <: Data](enqValid: Bool, enqBits: T, latency: Int): ValidIO[T] = { - if (latency == 0) { - val out = Wire(Valid(enqBits)) - out.valid <> enqValid - out.bits <> enqBits - out - } else { - val v = Reg(Bool(), next=enqValid, init=Bool(false)) - val b = RegEnable(enqBits, enqValid) - apply(v, b, latency-1) - } - } - def apply[T <: Data](enqValid: Bool, enqBits: T): ValidIO[T] = apply(enqValid, enqBits, 1) - def apply[T <: Data](enq: ValidIO[T], latency: Int = 1): ValidIO[T] = apply(enq.valid, enq.bits, latency) -} - -class Pipe[T <: Data](gen: T, latency: Int = 1) extends Module -{ - val io = new Bundle { - val enq = Valid(gen).flip - val deq = Valid(gen) - } - - io.deq <> Pipe(io.enq, latency) -} |
