riscv/rocket-chip
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fix D$ read/write concurrency bug

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This commit is contained in:
Andrew Waterman 2012-11-27 02:42:27 -08:00
parent 9c857b83f0
commit 90cae54ac4
2 changed files with 13 additions and 16 deletions
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9
rocket/src/main/scala/nbdcache.scala
View File

@ -600,17 +600,18 @@ class DataArray(implicit conf: DCacheConfig) extends Component {
if (conf.isNarrowRead) {
val waysPerMem = MEM_DATA_BITS/conf.databits
for (w <- 0 until conf.ways by waysPerMem) {
val wway_en = io.write.bits.way_en(w+waysPerMem-1,w)
val rway_en = io.read.bits.way_en(w+waysPerMem-1,w)
val resp = Vec(MEM_DATA_BITS/conf.databits){Reg{Bits(width = MEM_DATA_BITS)}}
val r_raddr = RegEn(io.read.bits.addr, io.read.valid)
for (p <- 0 until resp.size) {
val array = Mem(conf.sets*REFILL_CYCLES, seqRead = true){ Bits(width=MEM_DATA_BITS) }
val way_en = io.write.bits.way_en(w+waysPerMem-1,w)
when (way_en.orR && io.write.valid && io.write.bits.wmask(p)) {
when (wway_en.orR && io.write.valid && io.write.bits.wmask(p)) {
val data = Fill(waysPerMem, io.write.bits.data(conf.databits*(p+1)-1,conf.databits*p))
val mask = FillInterleaved(conf.databits, way_en)
val mask = FillInterleaved(conf.databits, wway_en)
array.write(waddr, data, mask)
}
when (way_en.orR && io.read.valid) {
when (rway_en.orR && io.read.valid) {
resp(p) := array(raddr)
}
}

20
rocket/src/main/scala/ptw.scala
View File

@ -41,11 +41,9 @@ class PTW(n: Int)(implicit conf: RocketConfiguration) extends Component
val r_req_vpn = Reg{Bits()}
val r_req_dest = Reg{Bits()}
val r_req_addr = Reg{UFix(width = PADDR_BITS.max(VADDR_BITS))}
val r_resp_perm = Reg{Bits()}
val r_pte = Reg{Bits()}
val vpn_idxs = (1 until levels).map(i => r_req_vpn((levels-i)*bitsPerLevel-1, (levels-i-1)*bitsPerLevel))
val vpn_idx = (2 until levels).foldRight(vpn_idxs(0))((i,j) => Mux(count === UFix(i-1), vpn_idxs(i-1), j))
val vpn_idx = AVec((0 until levels).map(i => (r_req_vpn >> (levels-i-1)*bitsPerLevel)(bitsPerLevel-1,0)))(count)
val arb = new RRArbiter(n)(UFix(width = VPN_BITS))
arb.io.in <> io.requestor.map(_.req)
@ -54,19 +52,18 @@ class PTW(n: Int)(implicit conf: RocketConfiguration) extends Component
when (arb.io.out.fire()) {
r_req_vpn := arb.io.out.bits
r_req_dest := arb.io.chosen
r_req_addr := Cat(io.dpath.ptbr(PADDR_BITS-1,PGIDX_BITS), arb.io.out.bits(VPN_BITS-1,VPN_BITS-bitsPerLevel)) << log2Up(conf.xprlen/8)
r_pte := Cat(io.dpath.ptbr(PADDR_BITS-1,PGIDX_BITS), io.mem.resp.bits.data(PGIDX_BITS-1,0))
}
when (io.mem.resp.valid) {
r_req_addr := Cat(io.mem.resp.bits.data(PADDR_BITS-1, PGIDX_BITS), vpn_idx).toUFix << log2Up(conf.xprlen/8)
r_resp_perm := io.mem.resp.bits.data(9,4);
r_pte := io.mem.resp.bits.data
}
io.mem.req.valid := state === s_req
io.mem.req.bits.phys := Bool(true)
io.mem.req.bits.cmd := M_XRD
io.mem.req.bits.typ := MT_D
io.mem.req.bits.addr := r_req_addr
io.mem.req.bits.addr := Cat(r_pte(PADDR_BITS-1,PGIDX_BITS), vpn_idx).toUFix << log2Up(conf.xprlen/8)
io.mem.req.bits.kill := Bool(false)
val resp_val = state === s_done || state === s_error
@ -75,15 +72,14 @@ class PTW(n: Int)(implicit conf: RocketConfiguration) extends Component
val resp_ptd = io.mem.resp.bits.data(1,0) === Bits(1)
val resp_pte = io.mem.resp.bits.data(1,0) === Bits(2)
val r_resp_ppn = r_req_addr >> PGIDX_BITS
val resp_ppns = (0 until levels-1).map(i => Cat(r_resp_ppn >> VPN_BITS-bitsPerLevel*(i+1), r_req_vpn(VPN_BITS-1-bitsPerLevel*(i+1), 0)))
val resp_ppn = (0 until levels-1).foldRight(r_resp_ppn)((i,j) => Mux(count === UFix(i), resp_ppns(i), j))
val r_resp_ppn = io.mem.req.bits.addr >> PGIDX_BITS
val resp_ppn = AVec((0 until levels-1).map(i => Cat(r_resp_ppn >> bitsPerLevel*(levels-i-1), r_req_vpn(bitsPerLevel*(levels-i-1)-1,0))) :+ r_resp_ppn)(count)
for (i <- 0 until io.requestor.size) {
val me = r_req_dest === UFix(i)
io.requestor(i).resp.valid := resp_val && me
io.requestor(i).resp.bits.error := resp_err
io.requestor(i).resp.bits.perm := r_resp_perm
io.requestor(i).resp.bits.perm := r_pte(9,4)
io.requestor(i).resp.bits.ppn := resp_ppn.toUFix
io.requestor(i).invalidate := io.dpath.invalidate
io.requestor(i).status := io.dpath.status