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rocket-chip/src/main/scala/diplomacy/Parameters.scala

255 lines
8.9 KiB
Scala

// See LICENSE.SiFive for license details.
package freechips.rocketchip.diplomacy
import Chisel._
import freechips.rocketchip.util.ShiftQueue
/** Options for memory regions */
object RegionType {
// Define the 'more relaxed than' ordering
val cases = Seq(CACHED, TRACKED, UNCACHED, UNCACHEABLE, PUT_EFFECTS, GET_EFFECTS)
sealed trait T extends Ordered[T] {
def compare(that: T): Int = cases.indexOf(that) compare cases.indexOf(this)
}
case object CACHED extends T
case object TRACKED extends T
case object UNCACHED extends T // not cached yet, but could be
case object UNCACHEABLE extends T // may spontaneously change contents
case object PUT_EFFECTS extends T // PUT_EFFECTS => UNCACHEABLE
case object GET_EFFECTS extends T // GET_EFFECTS => PUT_EFFECTS
}
// A non-empty half-open range; [start, end)
case class IdRange(start: Int, end: Int) extends Ordered[IdRange]
{
require (start >= 0, s"Ids cannot be negative, but got: $start.")
require (start < end, "Id ranges cannot be empty.")
def compare(x: IdRange) = {
val primary = (this.start - x.start).signum
val secondary = (x.end - this.end).signum
if (primary != 0) primary else secondary
}
def overlaps(x: IdRange) = start < x.end && x.start < end
def contains(x: IdRange) = start <= x.start && x.end <= end
// contains => overlaps (because empty is forbidden)
def contains(x: Int) = start <= x && x < end
def contains(x: UInt) =
if (size == 1) { // simple comparison
x === UInt(start)
} else {
// find index of largest different bit
val largestDeltaBit = log2Floor(start ^ (end-1))
val smallestCommonBit = largestDeltaBit + 1 // may not exist in x
val uncommonMask = (1 << smallestCommonBit) - 1
val uncommonBits = (x | UInt(0, width=smallestCommonBit))(largestDeltaBit, 0)
// the prefix must match exactly (note: may shift ALL bits away)
(x >> smallestCommonBit) === UInt(start >> smallestCommonBit) &&
// firrtl constant prop range analysis can eliminate these two:
UInt(start & uncommonMask) <= uncommonBits &&
uncommonBits <= UInt((end-1) & uncommonMask)
}
def shift(x: Int) = IdRange(start+x, end+x)
def size = end - start
def range = start until end
}
object IdRange
{
def overlaps(s: Seq[IdRange]) = if (s.isEmpty) None else {
val ranges = s.sorted
(ranges.tail zip ranges.init) find { case (a, b) => a overlaps b }
}
}
// An potentially empty inclusive range of 2-powers [min, max] (in bytes)
case class TransferSizes(min: Int, max: Int)
{
def this(x: Int) = this(x, x)
require (min <= max, s"Min transfer $min > max transfer $max")
require (min >= 0 && max >= 0, s"TransferSizes must be positive, got: ($min, $max)")
require (max == 0 || isPow2(max), s"TransferSizes must be a power of 2, got: $max")
require (min == 0 || isPow2(min), s"TransferSizes must be a power of 2, got: $min")
require (max == 0 || min != 0, s"TransferSize 0 is forbidden unless (0,0), got: ($min, $max)")
def none = min == 0
def contains(x: Int) = isPow2(x) && min <= x && x <= max
def containsLg(x: Int) = contains(1 << x)
def containsLg(x: UInt) =
if (none) Bool(false)
else if (min == max) { UInt(log2Ceil(min)) === x }
else { UInt(log2Ceil(min)) <= x && x <= UInt(log2Ceil(max)) }
def contains(x: TransferSizes) = x.none || (min <= x.min && x.max <= max)
def intersect(x: TransferSizes) =
if (x.max < min || max < x.min) TransferSizes.none
else TransferSizes(scala.math.max(min, x.min), scala.math.min(max, x.max))
override def toString() = "TransferSizes[%d, %d]".format(min, max)
}
object TransferSizes {
def apply(x: Int) = new TransferSizes(x)
val none = new TransferSizes(0)
implicit def asBool(x: TransferSizes) = !x.none
}
// AddressSets specify the address space managed by the manager
// Base is the base address, and mask are the bits consumed by the manager
// e.g: base=0x200, mask=0xff describes a device managing 0x200-0x2ff
// e.g: base=0x1000, mask=0xf0f decribes a device managing 0x1000-0x100f, 0x1100-0x110f, ...
case class AddressSet(base: BigInt, mask: BigInt) extends Ordered[AddressSet]
{
// Forbid misaligned base address (and empty sets)
require ((base & mask) == 0, s"Mis-aligned AddressSets are forbidden, got: ($base, $mask)")
require (base >= 0, s"AddressSet negative base is ambiguous: $base") // TL2 address widths are not fixed => negative is ambiguous
// We do allow negative mask (=> ignore all high bits)
def contains(x: BigInt) = ((x ^ base) & ~mask) == 0
def contains(x: UInt) = ((x ^ UInt(base)).zext() & SInt(~mask)) === SInt(0)
// turn x into an address contained in this set
def legalize(x: UInt): UInt = base.U | (mask.U & x)
// overlap iff bitwise: both care (~mask0 & ~mask1) => both equal (base0=base1)
def overlaps(x: AddressSet) = (~(mask | x.mask) & (base ^ x.base)) == 0
// contains iff bitwise: x.mask => mask && contains(x.base)
def contains(x: AddressSet) = ((x.mask | (base ^ x.base)) & ~mask) == 0
// The number of bytes to which the manager must be aligned
def alignment = ((mask + 1) & ~mask)
// Is this a contiguous memory range
def contiguous = alignment == mask+1
def finite = mask >= 0
def max = { require (finite, "Max cannot be calculated on infinite mask"); base | mask }
// Widen the match function to ignore all bits in imask
def widen(imask: BigInt) = AddressSet(base & ~imask, mask | imask)
// Return an AddressSet that only contains the addresses both sets contain
def intersect(x: AddressSet): Option[AddressSet] = {
if (!overlaps(x)) {
None
} else {
val r_mask = mask & x.mask
val r_base = base | x.base
Some(AddressSet(r_base, r_mask))
}
}
// AddressSets have one natural Ordering (the containment order, if contiguous)
def compare(x: AddressSet) = {
val primary = (this.base - x.base).signum // smallest address first
val secondary = (x.mask - this.mask).signum // largest mask first
if (primary != 0) primary else secondary
}
// We always want to see things in hex
override def toString() = {
if (mask >= 0) {
"AddressSet(0x%x, 0x%x)".format(base, mask)
} else {
"AddressSet(0x%x, ~0x%x)".format(base, ~mask)
}
}
def toRanges = {
require (finite, "Ranges cannot be calculated on infinite mask")
val size = alignment
val fragments = mask & ~(size-1)
val bits = bitIndexes(fragments)
(BigInt(0) until (BigInt(1) << bits.size)).map { i =>
val off = bitIndexes(i).foldLeft(base) { case (a, b) => a.setBit(bits(b)) }
AddressRange(off, size)
}
}
}
object AddressSet
{
val everything = AddressSet(0, -1)
def misaligned(base: BigInt, size: BigInt, tail: Seq[AddressSet] = Seq()): Seq[AddressSet] = {
if (size == 0) tail.reverse else {
val maxBaseAlignment = base & (-base) // 0 for infinite (LSB)
val maxSizeAlignment = BigInt(1) << log2Floor(size) // MSB of size
val step =
if (maxBaseAlignment == 0 || maxBaseAlignment > maxSizeAlignment)
maxSizeAlignment else maxBaseAlignment
misaligned(base+step, size-step, AddressSet(base, step-1) +: tail)
}
}
def unify(seq: Seq[AddressSet]): Seq[AddressSet] = {
val n = seq.size
val array = Array(seq:_*)
var filter = Array.fill(n) { false }
for (i <- 0 until n-1) { if (!filter(i)) {
for (j <- i+1 until n) { if (!filter(j)) {
val a = array(i)
val b = array(j)
if (a.mask == b.mask && isPow2(a.base ^ b.base)) {
val c_base = a.base & ~(a.base ^ b.base)
val c_mask = a.mask | (a.base ^ b.base)
filter.update(j, true)
array.update(i, AddressSet(c_base, c_mask))
}
}}
}}
val out = (array zip filter) flatMap { case (a, f) => if (f) None else Some(a) }
if (out.size != n) unify(out) else out.toList
}
}
case class BufferParams(depth: Int, flow: Boolean, pipe: Boolean)
{
require (depth >= 0, "Buffer depth must be >= 0")
def isDefined = depth > 0
def latency = if (isDefined && !flow) 1 else 0
def apply[T <: Data](x: DecoupledIO[T]) =
if (isDefined) Queue(x, depth, flow=flow, pipe=pipe)
else x
def sq[T <: Data](x: DecoupledIO[T]) =
if (!isDefined) x else {
val sq = Module(new ShiftQueue(x.bits, depth, flow=flow, pipe=pipe))
sq.io.enq <> x
sq.io.deq
}
override def toString() = "BufferParams:%d%s%s".format(depth, if (flow) "F" else "", if (pipe) "P" else "")
}
object BufferParams
{
implicit def apply(depth: Int): BufferParams = BufferParams(depth, false, false)
val default = BufferParams(2)
val none = BufferParams(0)
val flow = BufferParams(1, true, false)
val pipe = BufferParams(1, false, true)
}
case class TriStateValue(value: Boolean, set: Boolean)
{
def update(orig: Boolean) = if (set) value else orig
}
object TriStateValue
{
implicit def apply(value: Boolean): TriStateValue = TriStateValue(value, true)
def unset = TriStateValue(false, false)
}