xref: /XiangShan/src/main/scala/xiangshan/mem/lsqueue/LSQWrapper.scala (revision 5c5bd416ce761d956348a8e2fbbf268922371d8b)
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(UInt(2.W)))
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 needReplayFromRS = Vec(LoadPipelineWidth, Input(Bool()))
47    val sbuffer = Vec(StorePipelineWidth, Decoupled(new DCacheWordReq))
48    val ldout = Vec(2, DecoupledIO(new ExuOutput)) // writeback int load
49    val mmioStout = DecoupledIO(new ExuOutput) // writeback uncached store
50    val forward = Vec(LoadPipelineWidth, Flipped(new MaskedLoadForwardQueryIO))
51    val roq = Flipped(new RoqLsqIO)
52    val rollback = Output(Valid(new Redirect))
53    val dcache = Flipped(ValidIO(new Refill))
54    val uncache = new DCacheWordIO
55    val exceptionAddr = new ExceptionAddrIO
56    val sqempty = Output(Bool())
57    val issuePtrExt = Output(new SqPtr)
58    val storeIssue = Vec(StorePipelineWidth, Flipped(Valid(new ExuInput)))
59  })
60  val difftestIO = IO(new Bundle() {
61    val fromSQ = new Bundle() {
62      val storeCommit = Output(UInt(2.W))
63      val storeAddr   = Output(Vec(2, UInt(64.W)))
64      val storeData   = Output(Vec(2, UInt(64.W)))
65      val storeMask   = Output(Vec(2, UInt(8.W)))
66    }
67  })
68  difftestIO <> DontCare
69
70  val loadQueue = Module(new LoadQueue)
71  val storeQueue = Module(new StoreQueue)
72
73  // io.enq logic
74  // LSQ: send out canAccept when both load queue and store queue are ready
75  // Dispatch: send instructions to LSQ only when they are ready
76  io.enq.canAccept := loadQueue.io.enq.canAccept && storeQueue.io.enq.canAccept
77  loadQueue.io.enq.sqCanAccept := storeQueue.io.enq.canAccept
78  storeQueue.io.enq.lqCanAccept := loadQueue.io.enq.canAccept
79  for (i <- 0 until RenameWidth) {
80    loadQueue.io.enq.needAlloc(i) := io.enq.needAlloc(i)(0)
81    loadQueue.io.enq.req(i).valid := io.enq.needAlloc(i)(0) && io.enq.req(i).valid
82    loadQueue.io.enq.req(i).bits  := io.enq.req(i).bits
83
84    storeQueue.io.enq.needAlloc(i) := io.enq.needAlloc(i)(1)
85    storeQueue.io.enq.req(i).valid := io.enq.needAlloc(i)(1) && io.enq.req(i).valid
86    storeQueue.io.enq.req(i).bits  := io.enq.req(i).bits
87
88    io.enq.resp(i).lqIdx := loadQueue.io.enq.resp(i)
89    io.enq.resp(i).sqIdx := storeQueue.io.enq.resp(i)
90  }
91
92  // load queue wiring
93  loadQueue.io.brqRedirect <> io.brqRedirect
94  loadQueue.io.flush <> io.flush
95  loadQueue.io.loadIn <> io.loadIn
96  loadQueue.io.storeIn <> io.storeIn
97  loadQueue.io.loadDataForwarded <> io.loadDataForwarded
98  loadQueue.io.needReplayFromRS <> io.needReplayFromRS
99  loadQueue.io.ldout <> io.ldout
100  loadQueue.io.roq <> io.roq
101  loadQueue.io.rollback <> io.rollback
102  loadQueue.io.dcache <> io.dcache
103  loadQueue.io.exceptionAddr.lsIdx := io.exceptionAddr.lsIdx
104  loadQueue.io.exceptionAddr.isStore := DontCare
105
106  // store queue wiring
107  // storeQueue.io <> DontCare
108  storeQueue.io.brqRedirect <> io.brqRedirect
109  storeQueue.io.flush <> io.flush
110  storeQueue.io.storeIn <> io.storeIn
111  storeQueue.io.sbuffer <> io.sbuffer
112  storeQueue.io.mmioStout <> io.mmioStout
113  storeQueue.io.roq <> io.roq
114  storeQueue.io.exceptionAddr.lsIdx := io.exceptionAddr.lsIdx
115  storeQueue.io.exceptionAddr.isStore := DontCare
116  storeQueue.io.issuePtrExt <> io.issuePtrExt
117  storeQueue.io.storeIssue <> io.storeIssue
118
119  loadQueue.io.load_s1 <> io.forward
120  storeQueue.io.forward <> io.forward // overlap forwardMask & forwardData, DO NOT CHANGE SEQUENCE
121
122  storeQueue.io.sqempty <> io.sqempty
123
124  if (!env.FPGAPlatform) {
125    difftestIO.fromSQ <> storeQueue.difftestIO
126  }
127
128  io.exceptionAddr.vaddr := Mux(io.exceptionAddr.isStore, storeQueue.io.exceptionAddr.vaddr, loadQueue.io.exceptionAddr.vaddr)
129
130  // naive uncache arbiter
131  val s_idle :: s_load :: s_store :: Nil = Enum(3)
132  val pendingstate = RegInit(s_idle)
133
134  switch(pendingstate){
135    is(s_idle){
136      when(io.uncache.req.fire()){
137        pendingstate := Mux(loadQueue.io.uncache.req.valid, s_load, s_store)
138      }
139    }
140    is(s_load){
141      when(io.uncache.resp.fire()){
142        pendingstate := s_idle
143      }
144    }
145    is(s_store){
146      when(io.uncache.resp.fire()){
147        pendingstate := s_idle
148      }
149    }
150  }
151
152  loadQueue.io.uncache := DontCare
153  storeQueue.io.uncache := DontCare
154  loadQueue.io.uncache.resp.valid := false.B
155  storeQueue.io.uncache.resp.valid := false.B
156  when(loadQueue.io.uncache.req.valid){
157    io.uncache.req <> loadQueue.io.uncache.req
158  }.otherwise{
159    io.uncache.req <> storeQueue.io.uncache.req
160  }
161  when(pendingstate === s_load){
162    io.uncache.resp <> loadQueue.io.uncache.resp
163  }.otherwise{
164    io.uncache.resp <> storeQueue.io.uncache.resp
165  }
166
167  assert(!(loadQueue.io.uncache.req.valid && storeQueue.io.uncache.req.valid))
168  assert(!(loadQueue.io.uncache.resp.valid && storeQueue.io.uncache.resp.valid))
169  assert(!((loadQueue.io.uncache.resp.valid || storeQueue.io.uncache.resp.valid) && pendingstate === s_idle))
170
171}
172