xref: /XiangShan/src/main/scala/xiangshan/mem/pipeline/StoreUnit.scala (revision 3dff33d45876f9b7631252ab66a6c1b1201c86c0)
1package xiangshan.mem
2
3import chisel3._
4import chisel3.util._
5import utils._
6import xiangshan._
7import xiangshan.backend.decode.ImmUnion
8import xiangshan.cache._
9
10// Store Pipeline Stage 0
11// Generate addr, use addr to query DCache and DTLB
12class StoreUnit_S0 extends XSModule {
13  val io = IO(new Bundle() {
14    val in = Flipped(Decoupled(new ExuInput))
15    val rsIdx = Input(UInt(log2Up(IssQueSize).W))
16    val out = Decoupled(new LsPipelineBundle)
17    val dtlbReq = DecoupledIO(new TlbReq)
18  })
19
20  // send req to dtlb
21  val saddr_old = io.in.bits.src1 + SignExt(ImmUnion.S.toImm32(io.in.bits.uop.ctrl.imm), XLEN)
22  val imm12 = WireInit(io.in.bits.uop.ctrl.imm(11,0))
23  val saddr_lo = io.in.bits.src1(11,0) + Cat(0.U(1.W), imm12)
24  val saddr_hi = Mux(imm12(11),
25    Mux((saddr_lo(12)), io.in.bits.src1(VAddrBits-1, 12), io.in.bits.src1(VAddrBits-1, 12)+SignExt(1.U, VAddrBits-12)),
26    Mux((saddr_lo(12)), io.in.bits.src1(VAddrBits-1, 12)+1.U, io.in.bits.src1(VAddrBits-1, 12))
27  )
28  val saddr = Cat(saddr_hi, saddr_lo(11,0))
29  when(io.in.fire() && saddr(VAddrBits-1,0) =/= (io.in.bits.src1 + SignExt(ImmUnion.S.toImm32(io.in.bits.uop.ctrl.imm), XLEN))(VAddrBits-1,0)){
30    printf("saddr %x saddr_old %x\n", saddr, saddr_old(VAddrBits-1,0))
31  }
32
33  io.dtlbReq.bits.vaddr := saddr
34  io.dtlbReq.valid := io.in.valid
35  io.dtlbReq.bits.cmd := TlbCmd.write
36  io.dtlbReq.bits.roqIdx := io.in.bits.uop.roqIdx
37  io.dtlbReq.bits.debug.pc := io.in.bits.uop.cf.pc
38
39  io.out.bits := DontCare
40  io.out.bits.vaddr := saddr
41
42  io.out.bits.data := genWdata(io.in.bits.src2, io.in.bits.uop.ctrl.fuOpType(1,0))
43  when(io.in.bits.uop.ctrl.src2Type === SrcType.fp){
44    io.out.bits.data := io.in.bits.src2
45  } // not not touch fp store raw data
46  io.out.bits.uop := io.in.bits.uop
47  io.out.bits.miss := DontCare
48  io.out.bits.rsIdx := io.rsIdx
49  io.out.bits.mask := genWmask(io.out.bits.vaddr, io.in.bits.uop.ctrl.fuOpType(1,0))
50  io.out.valid := io.in.valid
51  io.in.ready := io.out.ready
52
53  // exception check
54  val addrAligned = LookupTree(io.in.bits.uop.ctrl.fuOpType(1,0), List(
55    "b00".U   -> true.B,              //b
56    "b01".U   -> (io.out.bits.vaddr(0) === 0.U),   //h
57    "b10".U   -> (io.out.bits.vaddr(1,0) === 0.U), //w
58    "b11".U   -> (io.out.bits.vaddr(2,0) === 0.U)  //d
59  ))
60  io.out.bits.uop.cf.exceptionVec(storeAddrMisaligned) := !addrAligned
61
62}
63
64// Load Pipeline Stage 1
65// TLB resp (send paddr to dcache)
66class StoreUnit_S1 extends XSModule {
67  val io = IO(new Bundle() {
68    val in = Flipped(Decoupled(new LsPipelineBundle))
69    val out = Decoupled(new LsPipelineBundle)
70    // val fp_out = Decoupled(new LsPipelineBundle)
71    val lsq = ValidIO(new LsPipelineBundle)
72    val dtlbResp = Flipped(DecoupledIO(new TlbResp))
73    val tlbFeedback = ValidIO(new TlbFeedback)
74  })
75
76  val s1_paddr = io.dtlbResp.bits.paddr
77  val s1_tlb_miss = io.dtlbResp.bits.miss
78
79  io.in.ready := true.B
80
81  io.dtlbResp.ready := true.B // TODO: why dtlbResp needs a ready?
82
83  // Send TLB feedback to store issue queue
84  io.tlbFeedback.valid := io.in.valid
85  io.tlbFeedback.bits.hit := !s1_tlb_miss
86  io.tlbFeedback.bits.rsIdx := io.in.bits.rsIdx
87  XSDebug(io.tlbFeedback.valid,
88    "S1 Store: tlbHit: %d roqIdx: %d\n",
89    io.tlbFeedback.bits.hit,
90    io.tlbFeedback.bits.rsIdx
91  )
92
93
94  // get paddr from dtlb, check if rollback is needed
95  // writeback store inst to lsq
96  io.lsq.valid := io.in.valid && !s1_tlb_miss// TODO: && ! FP
97  io.lsq.bits := io.in.bits
98  io.lsq.bits.paddr := s1_paddr
99  io.lsq.bits.miss := false.B
100  io.lsq.bits.mmio := io.dtlbResp.bits.mmio
101  io.lsq.bits.uop.cf.exceptionVec(storePageFault) := io.dtlbResp.bits.excp.pf.st
102  io.lsq.bits.uop.cf.exceptionVec(storeAccessFault) := io.dtlbResp.bits.excp.af.st
103
104  // mmio inst with exception will be writebacked immediately
105  val hasException = selectStore(io.out.bits.uop.cf.exceptionVec, false).asUInt.orR
106  io.out.valid := io.in.valid && (!io.out.bits.mmio || hasException) && !s1_tlb_miss
107  io.out.bits := io.lsq.bits
108
109  // encode data for fp store
110  when(io.in.bits.uop.ctrl.src2Type === SrcType.fp){
111	  io.lsq.bits.data := genWdata(ieee(io.in.bits.data), io.in.bits.uop.ctrl.fuOpType(1,0))
112	}
113
114}
115
116class StoreUnit_S2 extends XSModule {
117  val io = IO(new Bundle() {
118    val in = Flipped(Decoupled(new LsPipelineBundle))
119    val out = Decoupled(new LsPipelineBundle)
120  })
121
122  io.in.ready := true.B
123  io.out.bits := io.in.bits
124  io.out.valid := io.in.valid
125
126}
127
128class StoreUnit_S3 extends XSModule {
129  val io = IO(new Bundle() {
130    val in = Flipped(Decoupled(new LsPipelineBundle))
131    val stout = DecoupledIO(new ExuOutput) // writeback store
132  })
133
134  io.in.ready := true.B
135
136  io.stout.valid := io.in.valid
137  io.stout.bits.uop := io.in.bits.uop
138  io.stout.bits.data := DontCare
139  io.stout.bits.redirectValid := false.B
140  io.stout.bits.redirect := DontCare
141  io.stout.bits.debug.isMMIO := io.in.bits.mmio
142  io.stout.bits.debug.isPerfCnt := false.B
143  io.stout.bits.fflags := DontCare
144
145}
146
147class StoreUnit extends XSModule {
148  val io = IO(new Bundle() {
149    val stin = Flipped(Decoupled(new ExuInput))
150    val redirect = Flipped(ValidIO(new Redirect))
151    val flush = Input(Bool())
152    val tlbFeedback = ValidIO(new TlbFeedback)
153    val dtlb = new TlbRequestIO()
154    val rsIdx = Input(UInt(log2Up(IssQueSize).W))
155    val lsq = ValidIO(new LsPipelineBundle)
156    val stout = DecoupledIO(new ExuOutput) // writeback store
157  })
158
159  val store_s0 = Module(new StoreUnit_S0)
160  val store_s1 = Module(new StoreUnit_S1)
161  val store_s2 = Module(new StoreUnit_S2)
162  val store_s3 = Module(new StoreUnit_S3)
163
164  store_s0.io.in <> io.stin
165  store_s0.io.dtlbReq <> io.dtlb.req
166  store_s0.io.rsIdx := io.rsIdx
167
168  PipelineConnect(store_s0.io.out, store_s1.io.in, true.B, store_s0.io.out.bits.uop.roqIdx.needFlush(io.redirect, io.flush))
169
170  store_s1.io.lsq <> io.lsq // send result to sq
171  store_s1.io.dtlbResp <> io.dtlb.resp
172  store_s1.io.tlbFeedback <> io.tlbFeedback
173
174  PipelineConnect(store_s1.io.out, store_s2.io.in, true.B, store_s1.io.out.bits.uop.roqIdx.needFlush(io.redirect, io.flush))
175
176  PipelineConnect(store_s2.io.out, store_s3.io.in, true.B, store_s2.io.out.bits.uop.roqIdx.needFlush(io.redirect, io.flush))
177
178  store_s3.io.stout <> io.stout
179
180  private def printPipeLine(pipeline: LsPipelineBundle, cond: Bool, name: String): Unit = {
181    XSDebug(cond,
182      p"$name" + p" pc ${Hexadecimal(pipeline.uop.cf.pc)} " +
183        p"addr ${Hexadecimal(pipeline.vaddr)} -> ${Hexadecimal(pipeline.paddr)} " +
184        p"op ${Binary(pipeline.uop.ctrl.fuOpType)} " +
185        p"data ${Hexadecimal(pipeline.data)} " +
186        p"mask ${Hexadecimal(pipeline.mask)}\n"
187    )
188  }
189
190  printPipeLine(store_s0.io.out.bits, store_s0.io.out.valid, "S0")
191  printPipeLine(store_s1.io.out.bits, store_s1.io.out.valid, "S1")
192
193}
194