riscv/rocket-chip
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Merge master into rocc-fpu-port

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ebb33f2f4b658211960a4c6c023c139420c67212
This commit is contained in:
Colin Schmidt
2015-08-06 08:03:10 -07:00
parent f5b3649b73 fb5524372d
commit cab12635f8
23 changed files with 1045 additions and 1293 deletions
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40
rocket/src/main/scala/icache.scala
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@ -50,12 +50,12 @@ class Frontend(btb_updates_out_of_order: Boolean = false) extends FrontendModule
val tlb = Module(new TLB)
val s1_pc_ = Reg(UInt())
val s1_pc = s1_pc_ & SInt(-coreInstBytes) // discard PC LSBS (this propagates down the pipeline)
val s1_pc = ~(~s1_pc_ | (coreInstBytes-1)) // discard PC LSBS (this propagates down the pipeline)
val s1_same_block = Reg(Bool())
val s2_valid = Reg(init=Bool(true))
val s2_pc = Reg(init=UInt(START_ADDR))
val s2_btb_resp_valid = Reg(init=Bool(false))
val s2_btb_resp_bits = Reg(btb.io.resp.bits.clone)
val s2_btb_resp_bits = Reg(btb.io.resp.bits)
val s2_xcpt_if = Reg(init=Bool(false))
val icbuf = Module(new Queue(new ICacheResp, 1, pipe=true))
@ -94,7 +94,7 @@ class Frontend(btb_updates_out_of_order: Boolean = false) extends FrontendModule
btb.io.ras_update := io.cpu.ras_update
btb.io.invalidate := io.cpu.invalidate || io.ptw.invalidate
tlb.io.ptw <> io.ptw
io.ptw <> tlb.io.ptw
tlb.io.req.valid := !stall && !icmiss
tlb.io.req.bits.vpn := s1_pc >> UInt(pgIdxBits)
tlb.io.req.bits.asid := UInt(0)
@ -102,7 +102,7 @@ class Frontend(btb_updates_out_of_order: Boolean = false) extends FrontendModule
tlb.io.req.bits.instruction := Bool(true)
tlb.io.req.bits.store := Bool(false)
icache.io.mem <> io.mem
io.mem <> icache.io.mem
icache.io.req.valid := !stall && !s0_same_block
icache.io.req.bits.idx := io.cpu.npc
icache.io.invalidate := io.cpu.invalidate
@ -160,7 +160,7 @@ class ICache extends FrontendModule
val state = Reg(init=s_ready)
val invalidated = Reg(Bool())
val stall = !io.resp.ready
val rdy = Bool()
val rdy = Wire(Bool())
val refill_addr = Reg(UInt(width = paddrBits))
val s1_any_tag_hit = Bool()
@ -197,17 +197,13 @@ class ICache extends FrontendModule
val repl_way = if (isDM) UInt(0) else LFSR16(s1_miss)(log2Up(nWays)-1,0)
val entagbits = code.width(tagBits)
val tag_array = Mem(Bits(width = entagbits*nWays), nSets, seqRead = true)
val tag_raddr = Reg(UInt())
val tag_array = SeqMem(Bits(width = entagbits*nWays), nSets)
val tag_rdata = tag_array.read(s0_pgoff(untagBits-1,blockOffBits), !refill_done && s0_valid)
when (refill_done) {
val wmask = FillInterleaved(entagbits, if (isDM) Bits(1) else UIntToOH(repl_way))
val tag = code.encode(refill_tag).toUInt
tag_array.write(s1_idx, Fill(nWays, tag), wmask)
}
// /*.else*/when (s0_valid) { // uncomment ".else" to infer 6T SRAM
.elsewhen (s0_valid) {
tag_raddr := s0_pgoff(untagBits-1,blockOffBits)
}
val vb_array = Reg(init=Bits(0, nSets*nWays))
when (refill_done && !invalidated) {
@ -227,7 +223,7 @@ class ICache extends FrontendModule
for (i <- 0 until nWays) {
val s1_vb = !io.invalidate && vb_array(Cat(UInt(i), s1_pgoff(untagBits-1,blockOffBits))).toBool
val tag_out = tag_array(tag_raddr)(entagbits*(i+1)-1, entagbits*i)
val tag_out = tag_rdata(entagbits*(i+1)-1, entagbits*i)
val s1_tag_disparity = code.decode(tag_out).error
when (s1_valid && rdy && !stall) {
}
@ -238,20 +234,18 @@ class ICache extends FrontendModule
s1_any_tag_hit := s1_tag_hit.reduceLeft(_||_) && !s1_disparity.reduceLeft(_||_)
for (i <- 0 until nWays) {
val data_array = Mem(Bits(width = code.width(rowBits)), nSets*refillCycles, seqRead = true)
val s1_raddr = Reg(UInt())
when (narrow_grant.valid && repl_way === UInt(i)) {
val e_d = code.encode(narrow_grant.bits.data)
if(refillCycles > 1) data_array(Cat(s1_idx, refill_cnt)) := e_d
else data_array(s1_idx) := e_d
}
// /*.else*/when (s0_valid) { // uncomment ".else" to infer 6T SRAM
.elsewhen (s0_valid) {
s1_raddr := s0_pgoff(untagBits-1,blockOffBits-(if(refillCycles > 1) refill_cnt.getWidth else 0))
val data_array = SeqMem(Bits(width = code.width(rowBits)), nSets*refillCycles)
val wen = narrow_grant.valid && repl_way === UInt(i)
when (wen) {
val e_d = code.encode(narrow_grant.bits.data).toUInt
if(refillCycles > 1) data_array.write(Cat(s1_idx, refill_cnt), e_d)
else data_array.write(s1_idx, e_d)
}
val s0_raddr = s0_pgoff(untagBits-1,blockOffBits-(if(refillCycles > 1) refill_cnt.getWidth else 0))
val s1_rdata = data_array.read(s0_raddr, !wen && s0_valid)
// if s1_tag_match is critical, replace with partial tag check
s1_dout(i) := 0
when (s1_valid && rdy && !stall && (Bool(isDM) || s1_tag_match(i))) { s1_dout(i) := data_array(s1_raddr) }
when (s1_valid && rdy && !stall && (Bool(isDM) || s1_tag_match(i))) { s1_dout(i) := s1_rdata }
}
io.resp.bits.datablock := Mux1H(s1_tag_hit, s1_dout)