xref: /XiangShan/src/main/scala/xiangshan/mem/pipeline/StoreUnit.scala (revision 3802dba502b91d813c1e563035b876c4e6288166)
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 out = Decoupled(new LsPipelineBundle)
16    val dtlbReq = DecoupledIO(new TlbReq)
17  })
18
19  // send req to dtlb
20  val saddr = io.in.bits.src1 + SignExt(io.in.bits.uop.ctrl.imm(11,0), VAddrBits)
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.mask := genWmask(io.out.bits.vaddr, io.in.bits.uop.ctrl.fuOpType(1,0))
49  io.out.valid := io.in.valid
50  io.in.ready := io.out.ready
51
52  // exception check
53  val addrAligned = LookupTree(io.in.bits.uop.ctrl.fuOpType(1,0), List(
54    "b00".U   -> true.B,              //b
55    "b01".U   -> (io.out.bits.vaddr(0) === 0.U),   //h
56    "b10".U   -> (io.out.bits.vaddr(1,0) === 0.U), //w
57    "b11".U   -> (io.out.bits.vaddr(2,0) === 0.U)  //d
58  ))
59  io.out.bits.uop.cf.exceptionVec(storeAddrMisaligned) := !addrAligned
60
61}
62
63// Load Pipeline Stage 1
64// TLB resp (send paddr to dcache)
65class StoreUnit_S1 extends XSModule {
66  val io = IO(new Bundle() {
67    val in = Flipped(Decoupled(new LsPipelineBundle))
68    val out = Decoupled(new LsPipelineBundle)
69    // val fp_out = Decoupled(new LsPipelineBundle)
70    val lsq = ValidIO(new LsPipelineBundle)
71    val dtlbResp = Flipped(DecoupledIO(new TlbResp))
72    val tlbFeedback = ValidIO(new TlbFeedback)
73  })
74
75  val s1_paddr = io.dtlbResp.bits.paddr
76  val s1_tlb_miss = io.dtlbResp.bits.miss
77
78  io.in.ready := true.B
79
80  io.dtlbResp.ready := true.B // TODO: why dtlbResp needs a ready?
81
82  // Send TLB feedback to store issue queue
83  io.tlbFeedback.valid := io.in.valid
84  io.tlbFeedback.bits.hit := !s1_tlb_miss
85  io.tlbFeedback.bits.roqIdx := io.in.bits.uop.roqIdx
86  XSDebug(io.tlbFeedback.valid,
87    "S1 Store: tlbHit: %d roqIdx: %d\n",
88    io.tlbFeedback.bits.hit,
89    io.tlbFeedback.bits.roqIdx.asUInt
90  )
91
92
93  // get paddr from dtlb, check if rollback is needed
94  // writeback store inst to lsq
95  io.lsq.valid := io.in.valid && !s1_tlb_miss// TODO: && ! FP
96  io.lsq.bits := io.in.bits
97  io.lsq.bits.paddr := s1_paddr
98  io.lsq.bits.miss := false.B
99  io.lsq.bits.mmio := io.dtlbResp.bits.mmio
100  io.lsq.bits.uop.cf.exceptionVec(storePageFault) := io.dtlbResp.bits.excp.pf.st
101  io.lsq.bits.uop.cf.exceptionVec(storeAccessFault) := io.dtlbResp.bits.excp.af.st
102
103  // mmio inst with exception will be writebacked immediately
104  val hasException = selectStore(io.out.bits.uop.cf.exceptionVec, false).asUInt.orR
105  io.out.valid := io.in.valid && (!io.out.bits.mmio || hasException) && !s1_tlb_miss
106  io.out.bits := io.lsq.bits
107
108  // encode data for fp store
109  when(io.in.bits.uop.ctrl.src2Type === SrcType.fp){
110	  io.lsq.bits.data := genWdata(ieee(io.in.bits.data), io.in.bits.uop.ctrl.fuOpType(1,0))
111	}
112
113}
114
115class StoreUnit_S2 extends XSModule {
116  val io = IO(new Bundle() {
117    val in = Flipped(Decoupled(new LsPipelineBundle))
118    val out = Decoupled(new LsPipelineBundle)
119  })
120
121  io.in.ready := true.B
122  io.out.bits := io.in.bits
123  io.out.valid := io.in.valid
124
125}
126
127class StoreUnit_S3 extends XSModule {
128  val io = IO(new Bundle() {
129    val in = Flipped(Decoupled(new LsPipelineBundle))
130    val stout = DecoupledIO(new ExuOutput) // writeback store
131  })
132
133  io.in.ready := true.B
134
135  io.stout.valid := io.in.valid
136  io.stout.bits.uop := io.in.bits.uop
137  io.stout.bits.data := DontCare
138  io.stout.bits.redirectValid := false.B
139  io.stout.bits.redirect := DontCare
140  io.stout.bits.brUpdate := 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 tlbFeedback = ValidIO(new TlbFeedback)
152    val dtlb = new TlbRequestIO()
153    val lsq = ValidIO(new LsPipelineBundle)
154    val stout = DecoupledIO(new ExuOutput) // writeback store
155  })
156
157  val store_s0 = Module(new StoreUnit_S0)
158  val store_s1 = Module(new StoreUnit_S1)
159  val store_s2 = Module(new StoreUnit_S2)
160  val store_s3 = Module(new StoreUnit_S3)
161
162  store_s0.io.in <> io.stin
163  store_s0.io.dtlbReq <> io.dtlb.req
164
165  PipelineConnect(store_s0.io.out, store_s1.io.in, true.B, store_s0.io.out.bits.uop.roqIdx.needFlush(io.redirect))
166
167  store_s1.io.lsq <> io.lsq // send result to sq
168  store_s1.io.dtlbResp <> io.dtlb.resp
169  store_s1.io.tlbFeedback <> io.tlbFeedback
170
171  PipelineConnect(store_s1.io.out, store_s2.io.in, true.B, store_s1.io.out.bits.uop.roqIdx.needFlush(io.redirect))
172
173  PipelineConnect(store_s2.io.out, store_s3.io.in, true.B, store_s2.io.out.bits.uop.roqIdx.needFlush(io.redirect))
174
175  store_s3.io.stout <> io.stout
176
177  private def printPipeLine(pipeline: LsPipelineBundle, cond: Bool, name: String): Unit = {
178    XSDebug(cond,
179      p"$name" + p" pc ${Hexadecimal(pipeline.uop.cf.pc)} " +
180        p"addr ${Hexadecimal(pipeline.vaddr)} -> ${Hexadecimal(pipeline.paddr)} " +
181        p"op ${Binary(pipeline.uop.ctrl.fuOpType)} " +
182        p"data ${Hexadecimal(pipeline.data)} " +
183        p"mask ${Hexadecimal(pipeline.mask)}\n"
184    )
185  }
186
187  printPipeLine(store_s0.io.out.bits, store_s0.io.out.valid, "S0")
188  printPipeLine(store_s1.io.out.bits, store_s1.io.out.valid, "S1")
189
190}
191