riscv/rocket-chip
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fix way selection on D$ write upgrades

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This commit is contained in:
Andrew Waterman 2012-03-13 02:21:02 -07:00
parent fd29e00db0
commit d76b05bde1
1 changed files with 13 additions and 15 deletions
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28
rocket/src/main/scala/nbdcache.scala
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@ -94,7 +94,7 @@ class LoadDataGen extends Component {
class MSHRReq extends Bundle {
val tag_miss = Bool()
val old_state = UFix(width = 2)
val old_dirty = Bool()
val old_tag = Bits(width = TAG_BITS)
val tag = Bits(width = TAG_BITS)
@ -252,7 +252,7 @@ class MSHR(id: Int) extends Component with FourStateCoherence {
req := io.req_bits
when (io.req_bits.tag_miss) {
state := Mux(needsWriteback(io.req_bits.old_state), s_wb_req, s_refill_req)
state := Mux(io.req_bits.old_dirty, s_wb_req, s_refill_req)
}
}
@ -774,11 +774,11 @@ class HellaCacheUniproc extends HellaCache with FourStateCoherence {
meta_arb.io.in(2).bits.way_en := ~UFix(0, NWAYS)
val early_tag_nack = !meta_arb.io.in(2).ready
val cpu_req_tag = Cat(io.cpu.req_ppn, r_cpu_req_idx)(tagmsb,taglsb)
val tag_match_arr = (0 until NWAYS).map( w => isHit(r_cpu_req_cmd, meta.io.resp(w).state) && (meta.io.resp(w).tag === cpu_req_tag))
val tag_match_arr = (0 until NWAYS).map( w => isValid(meta.io.resp(w).state) && (meta.io.resp(w).tag === cpu_req_tag))
val tag_match = Cat(Bits(0),tag_match_arr:_*).orR
val tag_hit = r_cpu_req_val && tag_match
val tag_miss = r_cpu_req_val && !tag_match
val hit_way_oh = Cat(Bits(0),tag_match_arr.reverse:_*)(NWAYS-1, 0) //TODO: use Vec
val tag_hit_arr = (0 until NWAYS).map( w => isHit(r_cpu_req_cmd, meta.io.resp(w).state) && (meta.io.resp(w).tag === cpu_req_tag))
val tag_hit = Cat(Bits(0),tag_match_arr:_*).orR
val meta_resp_way_oh = Mux(meta.io.way_en === ~UFix(0, NWAYS), hit_way_oh, meta.io.way_en)
val data_resp_way_oh = Mux(data.io.way_en === ~UFix(0, NWAYS), hit_way_oh, data.io.way_en)
val meta_resp_mux = Mux1H(meta_resp_way_oh, meta.io.resp)
@ -809,8 +809,6 @@ class HellaCacheUniproc extends HellaCache with FourStateCoherence {
data_arb.io.in(4).bits.inner_req.offset := io.cpu.req_idx(offsetmsb,ramindexlsb)
data_arb.io.in(4).bits.inner_req.idx := io.cpu.req_idx(indexmsb,indexlsb)
data_arb.io.in(4).bits.inner_req.rw := Bool(false)
data_arb.io.in(4).bits.inner_req.wmask := UFix(0) // don't care
data_arb.io.in(4).bits.inner_req.data := io.mem.xact_rep.bits.data // don't care
data_arb.io.in(4).valid := io.cpu.req_val && req_read
data_arb.io.in(4).bits.way_en := ~UFix(0, NWAYS) // intiate load on all ways, mux after tag check
val early_load_nack = req_read && !data_arb.io.in(4).ready
@ -831,12 +829,12 @@ class HellaCacheUniproc extends HellaCache with FourStateCoherence {
val drain_store = drain_store_val && data_arb.io.in(2).ready
val p_amo = Reg(resetVal = Bool(false))
val p_store_rdy = !(p_store_valid && !drain_store) && !(mshr.io.data_req.valid || r_replay_amo || p_amo)
p_amo := tag_hit && r_req_amo && mshr.io.req.ready && !nack_hit || r_replay_amo
p_store_valid := p_store_valid && !drain_store || (tag_hit && r_req_store && mshr.io.req.ready && !nack_hit) || p_amo
p_amo := r_cpu_req_val && tag_hit && r_req_amo && mshr.io.req.ready && !nack_hit || r_replay_amo
p_store_valid := p_store_valid && !drain_store || (r_cpu_req_val && tag_hit && r_req_store && mshr.io.req.ready && !nack_hit) || p_amo
// tag update after a store to an exclusive clean line.
val new_hit_state = newStateOnHit(r_cpu_req_cmd, meta_resp_mux.state)
val set_hit_state = tag_hit && meta_resp_mux.state != new_hit_state
val set_hit_state = r_cpu_req_val && tag_hit && meta_resp_mux.state != new_hit_state
meta.io.state_req.bits.inner_req.rw := Bool(true)
meta.io.state_req.bits.inner_req.idx := Reg(r_cpu_req_idx(indexmsb,indexlsb))
meta.io.state_req.bits.inner_req.data.state := Reg(new_hit_state)
@ -858,8 +856,8 @@ class HellaCacheUniproc extends HellaCache with FourStateCoherence {
// miss handling
mshr.io.req.valid := r_cpu_req_val && r_req_readwrite && !nack_hit || flusher.io.mshr_req.valid
mshr.io.req.bits.tag_miss := tag_miss || flusher.io.mshr_req.valid
mshr.io.req.bits.old_state := meta_wb_mux.state
mshr.io.req.bits.tag_miss := !tag_hit || flusher.io.mshr_req.valid
mshr.io.req.bits.old_dirty := needsWriteback(meta_wb_mux.state) && !tag_match // don't wb upgrades
mshr.io.req.bits.old_tag := meta_wb_mux.tag
mshr.io.req.bits.tag := cpu_req_tag
mshr.io.req.bits.idx := r_cpu_req_idx(indexmsb,indexlsb)
@ -867,7 +865,7 @@ class HellaCacheUniproc extends HellaCache with FourStateCoherence {
mshr.io.req.bits.offset := r_cpu_req_idx(offsetmsb,0)
mshr.io.req.bits.cmd := r_cpu_req_cmd
mshr.io.req.bits.typ := r_cpu_req_type
mshr.io.req.bits.way_oh := replaced_way_oh
mshr.io.req.bits.way_oh := Mux(tag_match, hit_way_oh, replaced_way_oh)
mshr.io.req.bits.data := cpu_req_data
mshr.io.mem_rep <> io.mem.xact_rep
@ -932,9 +930,9 @@ class HellaCacheUniproc extends HellaCache with FourStateCoherence {
io.cpu.req_rdy := flusher.io.req.ready && !(r_cpu_req_val_ && r_req_flush) && !pending_fence
io.cpu.resp_nack := r_cpu_req_val_ && !io.cpu.req_kill && nack
io.cpu.resp_val := (tag_hit && !mshr.io.secondary_miss && !nack && r_req_read) || mshr.io.cpu_resp_val
io.cpu.resp_val := (r_cpu_req_val && tag_hit && !mshr.io.secondary_miss && !nack && r_req_read) || mshr.io.cpu_resp_val
io.cpu.resp_replay := mshr.io.cpu_resp_val
io.cpu.resp_miss := r_cpu_req_val_ && (!tag_match || mshr.io.secondary_miss) && r_req_read
io.cpu.resp_miss := r_cpu_req_val_ && (!tag_hit || mshr.io.secondary_miss) && r_req_read
io.cpu.resp_tag := Mux(mshr.io.cpu_resp_val, mshr.io.cpu_resp_tag, r_cpu_req_tag)
io.cpu.resp_type := loadgen.io.typ
io.cpu.resp_data := loadgen.io.dout