riscv/rocket-chip
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Improve L2 TLB coding style

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This commit is contained in:
Andrew Waterman 2017-07-26 02:22:43 -07:00
parent 5a9c673f41
commit 5a5b78b15e
1 changed files with 15 additions and 10 deletions
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25
src/main/scala/rocket/PTW.scala
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@ -136,7 +136,13 @@ class PTW(n: Int)(implicit edge: TLEdgeOut, p: Parameters) extends CoreModule()(
val l2_refill = RegNext(false.B)
io.dpath.perf.l2miss := false
val (l2_hit, l2_pte) = if (coreParams.nL2TLBEntries == 0) (false.B, Wire(new PTE)) else {
val code = new ParityCode
require(isPow2(coreParams.nL2TLBEntries))
val idxBits = log2Ceil(coreParams.nL2TLBEntries)
val tagBits = vpnBits - idxBits
class Entry extends Bundle {
val tag = UInt(width = tagBits)
val ppn = UInt(width = ppnBits)
val d = Bool()
val a = Bool()
@ -144,20 +150,19 @@ class PTW(n: Int)(implicit edge: TLEdgeOut, p: Parameters) extends CoreModule()(
val x = Bool()
val w = Bool()
val r = Bool()
override def cloneType = new Entry().asInstanceOf[this.type]
}
val code = new ParityCode
require(isPow2(coreParams.nL2TLBEntries))
val idxBits = log2Ceil(coreParams.nL2TLBEntries)
val tagBits = vpnBits - idxBits
val ram = SeqMem(coreParams.nL2TLBEntries, UInt(width = code.width(new Entry().getWidth + tagBits)))
val ram = SeqMem(coreParams.nL2TLBEntries, UInt(width = code.width(new Entry().getWidth)))
val g = Reg(UInt(width = coreParams.nL2TLBEntries))
val valid = RegInit(UInt(0, coreParams.nL2TLBEntries))
val (r_tag, r_idx) = Split(r_req.addr, idxBits)
when (l2_refill) {
val entry = Wire(new Entry)
entry := r_pte
ram.write(r_idx, code.encode(Cat(entry.asUInt, r_tag)))
entry.tag := r_tag
ram.write(r_idx, code.encode(entry.asUInt))
val mask = UIntToOH(r_idx)
valid := valid | mask
@ -176,11 +181,11 @@ class PTW(n: Int)(implicit edge: TLEdgeOut, p: Parameters) extends CoreModule()(
val s2_rdata = code.decode(RegEnable(s1_rdata, s1_valid))
when (s2_valid && s2_rdata.error) { valid := 0.U }
val (s2_entry, s2_tag) = Split(s2_rdata.uncorrected, tagBits)
val s2_hit = s2_valid && !s2_rdata.error && r_tag === s2_tag
io.dpath.perf.l2miss := s2_valid && !(r_tag === s2_tag)
val s2_entry = s2_rdata.uncorrected.asTypeOf(new Entry)
val s2_hit = s2_valid && !s2_rdata.error && r_tag === s2_entry.tag
io.dpath.perf.l2miss := s2_valid && !(r_tag === s2_entry.tag)
val s2_pte = Wire(new PTE)
s2_pte := s2_entry.asTypeOf(new Entry)
s2_pte := s2_entry
s2_pte.g := g(r_idx)
s2_pte.v := true