xref: /XiangShan/src/main/scala/xiangshan/mem/lsqueue/LSQWrapper.scala (revision 53c7ab8b2e79de0fa70909ea81a51720f666aaeb)
1package xiangshan.mem
2
3import chisel3._
4import chisel3.util._
5import utils._
6import xiangshan._
7import xiangshan.cache._
8import xiangshan.cache.{DCacheWordIO, DCacheLineIO, TlbRequestIO, MemoryOpConstants}
9import xiangshan.backend.LSUOpType
10import xiangshan.mem._
11import xiangshan.backend.roq.RoqLsqIO
12
13class ExceptionAddrIO extends XSBundle {
14  val lsIdx = Input(new LSIdx)
15  val isStore = Input(Bool())
16  val vaddr = Output(UInt(VAddrBits.W))
17}
18
19class FwdEntry extends XSBundle {
20  val valid = Bool()
21  val data = UInt(8.W)
22}
23
24// inflight miss block reqs
25class InflightBlockInfo extends XSBundle {
26  val block_addr = UInt(PAddrBits.W)
27  val valid = Bool()
28}
29
30class LsqEnqIO extends XSBundle {
31  val canAccept = Output(Bool())
32  val needAlloc = Vec(RenameWidth, Input(Bool()))
33  val req = Vec(RenameWidth, Flipped(ValidIO(new MicroOp)))
34  val resp = Vec(RenameWidth, Output(new LSIdx))
35}
36
37// Load / Store Queue Wrapper for XiangShan Out of Order LSU
38class LsqWrappper extends XSModule with HasDCacheParameters {
39  val io = IO(new Bundle() {
40    val enq = new LsqEnqIO
41    val brqRedirect = Flipped(ValidIO(new Redirect))
42    val flush = Input(Bool())
43    val loadIn = Vec(LoadPipelineWidth, Flipped(Valid(new LsPipelineBundle)))
44    val storeIn = Vec(StorePipelineWidth, Flipped(Valid(new LsPipelineBundle)))
45    val loadDataForwarded = Vec(LoadPipelineWidth, Input(Bool()))
46    val sbuffer = Vec(StorePipelineWidth, Decoupled(new DCacheWordReq))
47    val ldout = Vec(2, DecoupledIO(new ExuOutput)) // writeback int load
48    val mmioStout = DecoupledIO(new ExuOutput) // writeback uncached store
49    val forward = Vec(LoadPipelineWidth, Flipped(new LoadForwardQueryIO))
50    val roq = Flipped(new RoqLsqIO)
51    val rollback = Output(Valid(new Redirect))
52    val dcache = Flipped(ValidIO(new Refill))
53    val uncache = new DCacheWordIO
54    val exceptionAddr = new ExceptionAddrIO
55    val sqempty = Output(Bool())
56  })
57  val difftestIO = IO(new Bundle() {
58    val fromSQ = new Bundle() {
59      val storeCommit = Output(UInt(2.W))
60      val storeAddr   = Output(Vec(2, UInt(64.W)))
61      val storeData   = Output(Vec(2, UInt(64.W)))
62      val storeMask   = Output(Vec(2, UInt(8.W)))
63    }
64  })
65  difftestIO <> DontCare
66
67  val loadQueue = Module(new LoadQueue)
68  val storeQueue = Module(new StoreQueue)
69
70  // io.enq logic
71  // LSQ: send out canAccept when both load queue and store queue are ready
72  // Dispatch: send instructions to LSQ only when they are ready
73  io.enq.canAccept := loadQueue.io.enq.canAccept && storeQueue.io.enq.canAccept
74  loadQueue.io.enq.sqCanAccept := storeQueue.io.enq.canAccept
75  storeQueue.io.enq.lqCanAccept := loadQueue.io.enq.canAccept
76  for (i <- 0 until RenameWidth) {
77    val isStore = CommitType.lsInstIsStore(io.enq.req(i).bits.ctrl.commitType)
78
79    loadQueue.io.enq.needAlloc(i) := io.enq.needAlloc(i) && !isStore
80    loadQueue.io.enq.req(i).valid  := !isStore && io.enq.req(i).valid
81    loadQueue.io.enq.req(i).bits  := io.enq.req(i).bits
82
83    storeQueue.io.enq.needAlloc(i) := io.enq.needAlloc(i) && isStore
84    storeQueue.io.enq.req(i).valid :=  isStore && io.enq.req(i).valid
85    storeQueue.io.enq.req(i).bits := io.enq.req(i).bits
86
87    io.enq.resp(i).lqIdx := loadQueue.io.enq.resp(i)
88    io.enq.resp(i).sqIdx := storeQueue.io.enq.resp(i)
89  }
90
91  // load queue wiring
92  loadQueue.io.brqRedirect <> io.brqRedirect
93  loadQueue.io.flush <> io.flush
94  loadQueue.io.loadIn <> io.loadIn
95  loadQueue.io.storeIn <> io.storeIn
96  loadQueue.io.loadDataForwarded <> io.loadDataForwarded
97  loadQueue.io.ldout <> io.ldout
98  loadQueue.io.roq <> io.roq
99  loadQueue.io.rollback <> io.rollback
100  loadQueue.io.dcache <> io.dcache
101  loadQueue.io.exceptionAddr.lsIdx := io.exceptionAddr.lsIdx
102  loadQueue.io.exceptionAddr.isStore := DontCare
103
104  // store queue wiring
105  // storeQueue.io <> DontCare
106  storeQueue.io.brqRedirect <> io.brqRedirect
107  storeQueue.io.flush <> io.flush
108  storeQueue.io.storeIn <> io.storeIn
109  storeQueue.io.sbuffer <> io.sbuffer
110  storeQueue.io.mmioStout <> io.mmioStout
111  storeQueue.io.roq <> io.roq
112  storeQueue.io.exceptionAddr.lsIdx := io.exceptionAddr.lsIdx
113  storeQueue.io.exceptionAddr.isStore := DontCare
114
115  loadQueue.io.load_s1 <> io.forward
116  storeQueue.io.forward <> io.forward // overlap forwardMask & forwardData, DO NOT CHANGE SEQUENCE
117
118  storeQueue.io.sqempty <> io.sqempty
119
120  if (env.DualCoreDifftest) {
121    difftestIO.fromSQ <> storeQueue.difftestIO
122  }
123
124  io.exceptionAddr.vaddr := Mux(io.exceptionAddr.isStore, storeQueue.io.exceptionAddr.vaddr, loadQueue.io.exceptionAddr.vaddr)
125
126  // naive uncache arbiter
127  val s_idle :: s_load :: s_store :: Nil = Enum(3)
128  val pendingstate = RegInit(s_idle)
129
130  switch(pendingstate){
131    is(s_idle){
132      when(io.uncache.req.fire()){
133        pendingstate := Mux(loadQueue.io.uncache.req.valid, s_load, s_store)
134      }
135    }
136    is(s_load){
137      when(io.uncache.resp.fire()){
138        pendingstate := s_idle
139      }
140    }
141    is(s_store){
142      when(io.uncache.resp.fire()){
143        pendingstate := s_idle
144      }
145    }
146  }
147
148  loadQueue.io.uncache := DontCare
149  storeQueue.io.uncache := DontCare
150  loadQueue.io.uncache.resp.valid := false.B
151  storeQueue.io.uncache.resp.valid := false.B
152  when(loadQueue.io.uncache.req.valid){
153    io.uncache.req <> loadQueue.io.uncache.req
154  }.otherwise{
155    io.uncache.req <> storeQueue.io.uncache.req
156  }
157  when(pendingstate === s_load){
158    io.uncache.resp <> loadQueue.io.uncache.resp
159  }.otherwise{
160    io.uncache.resp <> storeQueue.io.uncache.resp
161  }
162
163  assert(!(loadQueue.io.uncache.req.valid && storeQueue.io.uncache.req.valid))
164  assert(!(loadQueue.io.uncache.resp.valid && storeQueue.io.uncache.resp.valid))
165  assert(!((loadQueue.io.uncache.resp.valid || storeQueue.io.uncache.resp.valid) && pendingstate === s_idle))
166
167}
168