xref: /XiangShan/src/main/scala/xiangshan/mem/pipeline/StoreUnit.scala (revision f27e03e01f25a4ef8524cc977899b76d8bd767a1)
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 = io.in.bits.src1 + SignExt(io.in.bits.uop.ctrl.imm(11,0), VAddrBits)
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(saddr_lo(12),
25    Mux(imm12(11), io.in.bits.src1(VAddrBits-1, 12), io.in.bits.src1(VAddrBits-1, 12)+1.U),
26    Mux(imm12(11), io.in.bits.src1(VAddrBits-1, 12)+SignExt(1.U, VAddrBits-12), io.in.bits.src1(VAddrBits-1, 12)),
27  )
28  val saddr = Cat(saddr_hi, saddr_lo(11,0))
29
30  io.dtlbReq.bits.vaddr := saddr
31  io.dtlbReq.valid := io.in.valid
32  io.dtlbReq.bits.cmd := TlbCmd.write
33  io.dtlbReq.bits.roqIdx := io.in.bits.uop.roqIdx
34  io.dtlbReq.bits.debug.pc := io.in.bits.uop.cf.pc
35
36  io.out.bits := DontCare
37  io.out.bits.vaddr := saddr
38
39  io.out.bits.data := genWdata(io.in.bits.src2, io.in.bits.uop.ctrl.fuOpType(1,0))
40  when(io.in.bits.uop.ctrl.src2Type === SrcType.fp){
41    io.out.bits.data := io.in.bits.src2
42  } // not not touch fp store raw data
43  io.out.bits.uop := io.in.bits.uop
44  io.out.bits.miss := DontCare
45  io.out.bits.rsIdx := io.rsIdx
46  io.out.bits.mask := genWmask(io.out.bits.vaddr, io.in.bits.uop.ctrl.fuOpType(1,0))
47  io.out.valid := io.in.valid
48  io.in.ready := io.out.ready
49
50  // exception check
51  val addrAligned = LookupTree(io.in.bits.uop.ctrl.fuOpType(1,0), List(
52    "b00".U   -> true.B,              //b
53    "b01".U   -> (io.out.bits.vaddr(0) === 0.U),   //h
54    "b10".U   -> (io.out.bits.vaddr(1,0) === 0.U), //w
55    "b11".U   -> (io.out.bits.vaddr(2,0) === 0.U)  //d
56  ))
57  io.out.bits.uop.cf.exceptionVec(storeAddrMisaligned) := !addrAligned
58
59}
60
61// Load Pipeline Stage 1
62// TLB resp (send paddr to dcache)
63class StoreUnit_S1 extends XSModule {
64  val io = IO(new Bundle() {
65    val in = Flipped(Decoupled(new LsPipelineBundle))
66    val out = Decoupled(new LsPipelineBundle)
67    // val fp_out = Decoupled(new LsPipelineBundle)
68    val lsq = ValidIO(new LsPipelineBundle)
69    val dtlbResp = Flipped(DecoupledIO(new TlbResp))
70    val tlbFeedback = ValidIO(new TlbFeedback)
71  })
72
73  val s1_paddr = io.dtlbResp.bits.paddr
74  val s1_tlb_miss = io.dtlbResp.bits.miss
75  val s1_mmio = io.dtlbResp.bits.mmio
76  val s1_exception = selectStore(io.out.bits.uop.cf.exceptionVec, false).asUInt.orR
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.rsIdx := io.in.bits.rsIdx
86  XSDebug(io.tlbFeedback.valid,
87    "S1 Store: tlbHit: %d roqIdx: %d\n",
88    io.tlbFeedback.bits.hit,
89    io.tlbFeedback.bits.rsIdx
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 := s1_mmio && !s1_exception
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  io.out.valid := io.in.valid && (!io.out.bits.mmio || s1_exception) && !s1_tlb_miss
105  io.out.bits := io.lsq.bits
106
107  // encode data for fp store
108  when(io.in.bits.uop.ctrl.src2Type === SrcType.fp){
109	  io.lsq.bits.data := genWdata(ieee(io.in.bits.data), io.in.bits.uop.ctrl.fuOpType(1,0))
110	}
111
112}
113
114class StoreUnit_S2 extends XSModule {
115  val io = IO(new Bundle() {
116    val in = Flipped(Decoupled(new LsPipelineBundle))
117    val out = Decoupled(new LsPipelineBundle)
118  })
119
120  io.in.ready := true.B
121  io.out.bits := io.in.bits
122  io.out.valid := io.in.valid
123
124}
125
126class StoreUnit_S3 extends XSModule {
127  val io = IO(new Bundle() {
128    val in = Flipped(Decoupled(new LsPipelineBundle))
129    val stout = DecoupledIO(new ExuOutput) // writeback store
130  })
131
132  io.in.ready := true.B
133
134  io.stout.valid := io.in.valid
135  io.stout.bits.uop := io.in.bits.uop
136  io.stout.bits.data := DontCare
137  io.stout.bits.redirectValid := false.B
138  io.stout.bits.redirect := DontCare
139  io.stout.bits.debug.isMMIO := io.in.bits.mmio
140  io.stout.bits.debug.paddr := DontCare
141  io.stout.bits.debug.isPerfCnt := false.B
142  io.stout.bits.fflags := DontCare
143
144}
145
146class StoreUnit extends XSModule {
147  val io = IO(new Bundle() {
148    val stin = Flipped(Decoupled(new ExuInput))
149    val redirect = Flipped(ValidIO(new Redirect))
150    val flush = Input(Bool())
151    val tlbFeedback = ValidIO(new TlbFeedback)
152    val dtlb = new TlbRequestIO()
153    val rsIdx = Input(UInt(log2Up(IssQueSize).W))
154    val lsq = ValidIO(new LsPipelineBundle)
155    val stout = DecoupledIO(new ExuOutput) // writeback store
156  })
157
158  val store_s0 = Module(new StoreUnit_S0)
159  val store_s1 = Module(new StoreUnit_S1)
160  val store_s2 = Module(new StoreUnit_S2)
161  val store_s3 = Module(new StoreUnit_S3)
162
163  store_s0.io.in <> io.stin
164  store_s0.io.dtlbReq <> io.dtlb.req
165  store_s0.io.rsIdx := io.rsIdx
166
167  PipelineConnect(store_s0.io.out, store_s1.io.in, true.B, store_s0.io.out.bits.uop.roqIdx.needFlush(io.redirect, io.flush))
168
169  store_s1.io.lsq <> io.lsq // send result to sq
170  store_s1.io.dtlbResp <> io.dtlb.resp
171  store_s1.io.tlbFeedback <> io.tlbFeedback
172
173  PipelineConnect(store_s1.io.out, store_s2.io.in, true.B, store_s1.io.out.bits.uop.roqIdx.needFlush(io.redirect, io.flush))
174
175  PipelineConnect(store_s2.io.out, store_s3.io.in, true.B, store_s2.io.out.bits.uop.roqIdx.needFlush(io.redirect, io.flush))
176
177  store_s3.io.stout <> io.stout
178
179  private def printPipeLine(pipeline: LsPipelineBundle, cond: Bool, name: String): Unit = {
180    XSDebug(cond,
181      p"$name" + p" pc ${Hexadecimal(pipeline.uop.cf.pc)} " +
182        p"addr ${Hexadecimal(pipeline.vaddr)} -> ${Hexadecimal(pipeline.paddr)} " +
183        p"op ${Binary(pipeline.uop.ctrl.fuOpType)} " +
184        p"data ${Hexadecimal(pipeline.data)} " +
185        p"mask ${Hexadecimal(pipeline.mask)}\n"
186    )
187  }
188
189  printPipeLine(store_s0.io.out.bits, store_s0.io.out.valid, "S0")
190  printPipeLine(store_s1.io.out.bits, store_s1.io.out.valid, "S1")
191
192}
193