xref: /XiangShan/src/main/scala/xiangshan/mem/lsqueue/LSQWrapper.scala (revision c6d439803a044ea209139672b25e35fe8d7f4aa0)
1/***************************************************************************************
2* Copyright (c) 2020-2021 Institute of Computing Technology, Chinese Academy of Sciences
3*
4* XiangShan is licensed under Mulan PSL v2.
5* You can use this software according to the terms and conditions of the Mulan PSL v2.
6* You may obtain a copy of Mulan PSL v2 at:
7*          http://license.coscl.org.cn/MulanPSL2
8*
9* THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
10* EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
11* MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
12*
13* See the Mulan PSL v2 for more details.
14***************************************************************************************/
15
16package xiangshan.mem
17
18import chipsalliance.rocketchip.config.Parameters
19import chisel3._
20import chisel3.util._
21import utils._
22import xiangshan._
23import xiangshan.cache._
24import xiangshan.cache.{DCacheWordIO, DCacheLineIO, TlbRequestIO, MemoryOpConstants}
25import xiangshan.mem._
26import xiangshan.backend.roq.RoqLsqIO
27
28class ExceptionAddrIO(implicit p: Parameters) extends XSBundle {
29  val lsIdx = Input(new LSIdx)
30  val isStore = Input(Bool())
31  val vaddr = Output(UInt(VAddrBits.W))
32}
33
34class FwdEntry extends Bundle {
35  val valid = Bool()
36  val data = UInt(8.W)
37}
38
39// inflight miss block reqs
40class InflightBlockInfo(implicit p: Parameters) extends XSBundle {
41  val block_addr = UInt(PAddrBits.W)
42  val valid = Bool()
43}
44
45class LsqEnqIO(implicit p: Parameters) extends XSBundle {
46  val canAccept = Output(Bool())
47  val needAlloc = Vec(RenameWidth, Input(UInt(2.W)))
48  val req = Vec(RenameWidth, Flipped(ValidIO(new MicroOp)))
49  val resp = Vec(RenameWidth, Output(new LSIdx))
50}
51
52// Load / Store Queue Wrapper for XiangShan Out of Order LSU
53class LsqWrappper(implicit p: Parameters) extends XSModule with HasDCacheParameters {
54  val io = IO(new Bundle() {
55    val enq = new LsqEnqIO
56    val brqRedirect = Flipped(ValidIO(new Redirect))
57    val flush = Input(Bool())
58    val loadIn = Vec(LoadPipelineWidth, Flipped(Valid(new LsPipelineBundle)))
59    val storeIn = Vec(StorePipelineWidth, Flipped(Valid(new LsPipelineBundle)))
60    val storeDataIn = Vec(StorePipelineWidth, Flipped(Valid(new StoreDataBundle))) // store data, send to sq from rs
61    val loadDataForwarded = Vec(LoadPipelineWidth, Input(Bool()))
62    val needReplayFromRS = Vec(LoadPipelineWidth, Input(Bool()))
63    val sbuffer = Vec(StorePipelineWidth, Decoupled(new DCacheWordReq))
64    val ldout = Vec(2, DecoupledIO(new ExuOutput)) // writeback int load
65    val mmioStout = DecoupledIO(new ExuOutput) // writeback uncached store
66    val forward = Vec(LoadPipelineWidth, Flipped(new PipeLoadForwardQueryIO))
67    val roq = Flipped(new RoqLsqIO)
68    val rollback = Output(Valid(new Redirect))
69    val dcache = Flipped(ValidIO(new Refill))
70    val uncache = new DCacheWordIO
71    val exceptionAddr = new ExceptionAddrIO
72    val sqempty = Output(Bool())
73    val issuePtrExt = Output(new SqPtr)
74    val storeIssue = Vec(StorePipelineWidth, Flipped(Valid(new ExuInput)))
75    val sqFull = Output(Bool())
76    val lqFull = Output(Bool())
77  })
78
79  val loadQueue = Module(new LoadQueue)
80  val storeQueue = Module(new StoreQueue)
81
82  // io.enq logic
83  // LSQ: send out canAccept when both load queue and store queue are ready
84  // Dispatch: send instructions to LSQ only when they are ready
85  io.enq.canAccept := loadQueue.io.enq.canAccept && storeQueue.io.enq.canAccept
86  loadQueue.io.enq.sqCanAccept := storeQueue.io.enq.canAccept
87  storeQueue.io.enq.lqCanAccept := loadQueue.io.enq.canAccept
88  for (i <- 0 until RenameWidth) {
89    loadQueue.io.enq.needAlloc(i) := io.enq.needAlloc(i)(0)
90    loadQueue.io.enq.req(i).valid := io.enq.needAlloc(i)(0) && io.enq.req(i).valid
91    loadQueue.io.enq.req(i).bits  := io.enq.req(i).bits
92
93    storeQueue.io.enq.needAlloc(i) := io.enq.needAlloc(i)(1)
94    storeQueue.io.enq.req(i).valid := io.enq.needAlloc(i)(1) && io.enq.req(i).valid
95    storeQueue.io.enq.req(i).bits  := io.enq.req(i).bits
96
97    io.enq.resp(i).lqIdx := loadQueue.io.enq.resp(i)
98    io.enq.resp(i).sqIdx := storeQueue.io.enq.resp(i)
99  }
100
101  // load queue wiring
102  loadQueue.io.brqRedirect <> io.brqRedirect
103  loadQueue.io.flush <> io.flush
104  loadQueue.io.loadIn <> io.loadIn
105  loadQueue.io.storeIn <> io.storeIn
106  loadQueue.io.loadDataForwarded <> io.loadDataForwarded
107  loadQueue.io.needReplayFromRS <> io.needReplayFromRS
108  loadQueue.io.ldout <> io.ldout
109  loadQueue.io.roq <> io.roq
110  loadQueue.io.rollback <> io.rollback
111  loadQueue.io.dcache <> io.dcache
112  loadQueue.io.exceptionAddr.lsIdx := io.exceptionAddr.lsIdx
113  loadQueue.io.exceptionAddr.isStore := DontCare
114
115  // store queue wiring
116  // storeQueue.io <> DontCare
117  storeQueue.io.brqRedirect <> io.brqRedirect
118  storeQueue.io.flush <> io.flush
119  storeQueue.io.storeIn <> io.storeIn
120  storeQueue.io.storeDataIn <> io.storeDataIn
121  storeQueue.io.sbuffer <> io.sbuffer
122  storeQueue.io.mmioStout <> io.mmioStout
123  storeQueue.io.roq <> io.roq
124  storeQueue.io.exceptionAddr.lsIdx := io.exceptionAddr.lsIdx
125  storeQueue.io.exceptionAddr.isStore := DontCare
126  storeQueue.io.issuePtrExt <> io.issuePtrExt
127  storeQueue.io.storeIssue <> io.storeIssue
128
129  loadQueue.io.load_s1 <> io.forward
130  storeQueue.io.forward <> io.forward // overlap forwardMask & forwardData, DO NOT CHANGE SEQUENCE
131
132  storeQueue.io.sqempty <> io.sqempty
133
134  io.exceptionAddr.vaddr := Mux(io.exceptionAddr.isStore, storeQueue.io.exceptionAddr.vaddr, loadQueue.io.exceptionAddr.vaddr)
135
136  // naive uncache arbiter
137  val s_idle :: s_load :: s_store :: Nil = Enum(3)
138  val pendingstate = RegInit(s_idle)
139
140  switch(pendingstate){
141    is(s_idle){
142      when(io.uncache.req.fire()){
143        pendingstate := Mux(loadQueue.io.uncache.req.valid, s_load, s_store)
144      }
145    }
146    is(s_load){
147      when(io.uncache.resp.fire()){
148        pendingstate := s_idle
149      }
150    }
151    is(s_store){
152      when(io.uncache.resp.fire()){
153        pendingstate := s_idle
154      }
155    }
156  }
157
158  loadQueue.io.uncache := DontCare
159  storeQueue.io.uncache := DontCare
160  loadQueue.io.uncache.resp.valid := false.B
161  storeQueue.io.uncache.resp.valid := false.B
162  when(loadQueue.io.uncache.req.valid){
163    io.uncache.req <> loadQueue.io.uncache.req
164  }.otherwise{
165    io.uncache.req <> storeQueue.io.uncache.req
166  }
167  when(pendingstate === s_load){
168    io.uncache.resp <> loadQueue.io.uncache.resp
169  }.otherwise{
170    io.uncache.resp <> storeQueue.io.uncache.resp
171  }
172
173  assert(!(loadQueue.io.uncache.req.valid && storeQueue.io.uncache.req.valid))
174  assert(!(loadQueue.io.uncache.resp.valid && storeQueue.io.uncache.resp.valid))
175  assert(!((loadQueue.io.uncache.resp.valid || storeQueue.io.uncache.resp.valid) && pendingstate === s_idle))
176
177  io.lqFull := loadQueue.io.lqFull
178  io.sqFull := storeQueue.io.sqFull
179}
180