xref: /XiangShan/src/main/scala/xiangshan/mem/pipeline/StoreUnit.scala (revision 2199a01c65d5a7bf503c4b40771336a50a6f1122)
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(ImmUnion.S.toImm32(io.in.bits.uop.ctrl.imm), XLEN)
21
22  io.dtlbReq.bits.vaddr := saddr
23  io.dtlbReq.valid := io.in.valid
24  io.dtlbReq.bits.cmd := TlbCmd.write
25  io.dtlbReq.bits.roqIdx := io.in.bits.uop.roqIdx
26  io.dtlbReq.bits.debug.pc := io.in.bits.uop.cf.pc
27
28  io.out.bits := DontCare
29  io.out.bits.vaddr := saddr
30
31  io.out.bits.data := genWdata(io.in.bits.src2, io.in.bits.uop.ctrl.fuOpType(1,0))
32  when(io.in.bits.uop.ctrl.src2Type === SrcType.fp){
33    io.out.bits.data := io.in.bits.src2
34  } // not not touch fp store raw data
35  io.out.bits.uop := io.in.bits.uop
36  io.out.bits.miss := DontCare
37  io.out.bits.mask := genWmask(io.out.bits.vaddr, io.in.bits.uop.ctrl.fuOpType(1,0))
38  io.out.valid := io.in.valid
39  io.in.ready := io.out.ready
40
41  // exception check
42  val addrAligned = LookupTree(io.in.bits.uop.ctrl.fuOpType(1,0), List(
43    "b00".U   -> true.B,              //b
44    "b01".U   -> (io.out.bits.vaddr(0) === 0.U),   //h
45    "b10".U   -> (io.out.bits.vaddr(1,0) === 0.U), //w
46    "b11".U   -> (io.out.bits.vaddr(2,0) === 0.U)  //d
47  ))
48  io.out.bits.uop.cf.exceptionVec(storeAddrMisaligned) := !addrAligned
49
50}
51
52// Load Pipeline Stage 1
53// TLB resp (send paddr to dcache)
54class StoreUnit_S1 extends XSModule {
55  val io = IO(new Bundle() {
56    val in = Flipped(Decoupled(new LsPipelineBundle))
57    val out = Decoupled(new LsPipelineBundle)
58    // val fp_out = Decoupled(new LsPipelineBundle)
59    val lsq = ValidIO(new LsPipelineBundle)
60    val dtlbResp = Flipped(DecoupledIO(new TlbResp))
61    val tlbFeedback = ValidIO(new TlbFeedback)
62  })
63
64  val s1_paddr = io.dtlbResp.bits.paddr
65  val s1_tlb_miss = io.dtlbResp.bits.miss
66
67  io.in.ready := true.B
68
69  io.dtlbResp.ready := true.B // TODO: why dtlbResp needs a ready?
70
71  // Send TLB feedback to store issue queue
72  io.tlbFeedback.valid := io.in.valid
73  io.tlbFeedback.bits.hit := !s1_tlb_miss
74  io.tlbFeedback.bits.roqIdx := io.in.bits.uop.roqIdx
75  XSDebug(io.tlbFeedback.valid,
76    "S1 Store: tlbHit: %d roqIdx: %d\n",
77    io.tlbFeedback.bits.hit,
78    io.tlbFeedback.bits.roqIdx.asUInt
79  )
80
81
82  // get paddr from dtlb, check if rollback is needed
83  // writeback store inst to lsq
84  io.lsq.valid := io.in.valid && !s1_tlb_miss// TODO: && ! FP
85  io.lsq.bits := io.in.bits
86  io.lsq.bits.paddr := s1_paddr
87  io.lsq.bits.miss := false.B
88  io.lsq.bits.mmio := io.dtlbResp.bits.mmio
89  io.lsq.bits.uop.cf.exceptionVec(storePageFault) := io.dtlbResp.bits.excp.pf.st
90  io.lsq.bits.uop.cf.exceptionVec(storeAccessFault) := io.dtlbResp.bits.excp.af.st
91
92  // mmio inst with exception will be writebacked immediately
93  val hasException = selectStore(io.out.bits.uop.cf.exceptionVec, false).asUInt.orR
94  io.out.valid := io.in.valid && (!io.out.bits.mmio || hasException) && !s1_tlb_miss
95  io.out.bits := io.lsq.bits
96
97  // encode data for fp store
98  when(io.in.bits.uop.ctrl.src2Type === SrcType.fp){
99	  io.lsq.bits.data := genWdata(ieee(io.in.bits.data), io.in.bits.uop.ctrl.fuOpType(1,0))
100	}
101
102}
103
104class StoreUnit_S2 extends XSModule {
105  val io = IO(new Bundle() {
106    val in = Flipped(Decoupled(new LsPipelineBundle))
107    val out = Decoupled(new LsPipelineBundle)
108  })
109
110  io.in.ready := true.B
111  io.out.bits := io.in.bits
112  io.out.valid := io.in.valid
113
114}
115
116class StoreUnit_S3 extends XSModule {
117  val io = IO(new Bundle() {
118    val in = Flipped(Decoupled(new LsPipelineBundle))
119    val stout = DecoupledIO(new ExuOutput) // writeback store
120  })
121
122  io.in.ready := true.B
123
124  io.stout.valid := io.in.valid
125  io.stout.bits.uop := io.in.bits.uop
126  io.stout.bits.data := DontCare
127  io.stout.bits.redirectValid := false.B
128  io.stout.bits.redirect := DontCare
129  io.stout.bits.brUpdate := DontCare
130  io.stout.bits.debug.isMMIO := io.in.bits.mmio
131  io.stout.bits.debug.isPerfCnt := false.B
132  io.stout.bits.fflags := DontCare
133
134}
135
136class StoreUnit extends XSModule {
137  val io = IO(new Bundle() {
138    val stin = Flipped(Decoupled(new ExuInput))
139    val redirect = Flipped(ValidIO(new Redirect))
140    val tlbFeedback = ValidIO(new TlbFeedback)
141    val dtlb = new TlbRequestIO()
142    val lsq = ValidIO(new LsPipelineBundle)
143    val stout = DecoupledIO(new ExuOutput) // writeback store
144  })
145
146  val store_s0 = Module(new StoreUnit_S0)
147  val store_s1 = Module(new StoreUnit_S1)
148  val store_s2 = Module(new StoreUnit_S2)
149  val store_s3 = Module(new StoreUnit_S3)
150
151  store_s0.io.in <> io.stin
152  store_s0.io.dtlbReq <> io.dtlb.req
153
154  PipelineConnect(store_s0.io.out, store_s1.io.in, true.B, store_s0.io.out.bits.uop.roqIdx.needFlush(io.redirect))
155
156  store_s1.io.lsq <> io.lsq // send result to sq
157  store_s1.io.dtlbResp <> io.dtlb.resp
158  store_s1.io.tlbFeedback <> io.tlbFeedback
159
160  PipelineConnect(store_s1.io.out, store_s2.io.in, true.B, store_s1.io.out.bits.uop.roqIdx.needFlush(io.redirect))
161
162  PipelineConnect(store_s2.io.out, store_s3.io.in, true.B, store_s2.io.out.bits.uop.roqIdx.needFlush(io.redirect))
163
164  store_s3.io.stout <> io.stout
165
166  private def printPipeLine(pipeline: LsPipelineBundle, cond: Bool, name: String): Unit = {
167    XSDebug(cond,
168      p"$name" + p" pc ${Hexadecimal(pipeline.uop.cf.pc)} " +
169        p"addr ${Hexadecimal(pipeline.vaddr)} -> ${Hexadecimal(pipeline.paddr)} " +
170        p"op ${Binary(pipeline.uop.ctrl.fuOpType)} " +
171        p"data ${Hexadecimal(pipeline.data)} " +
172        p"mask ${Hexadecimal(pipeline.mask)}\n"
173    )
174  }
175
176  printPipeLine(store_s0.io.out.bits, store_s0.io.out.valid, "S0")
177  printPipeLine(store_s1.io.out.bits, store_s1.io.out.valid, "S1")
178
179}
180