xref: /XiangShan/src/main/scala/xiangshan/backend/fu/CSR.scala (revision eb163ef08fc5ac1da1f32d948699bd6de053e444)
1/***************************************************************************************
2* Copyright (c) 2020-2021 Institute of Computing Technology, Chinese Academy of Sciences
3* Copyright (c) 2020-2021 Peng Cheng Laboratory
4*
5* XiangShan is licensed under Mulan PSL v2.
6* You can use this software according to the terms and conditions of the Mulan PSL v2.
7* You may obtain a copy of Mulan PSL v2 at:
8*          http://license.coscl.org.cn/MulanPSL2
9*
10* THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
11* EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
12* MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
13*
14* See the Mulan PSL v2 for more details.
15***************************************************************************************/
16
17package xiangshan.backend.fu
18
19import chipsalliance.rocketchip.config.Parameters
20import chisel3._
21import chisel3.util._
22import difftest._
23import freechips.rocketchip.util._
24import utils.MaskedRegMap.WritableMask
25import utils._
26import xiangshan.ExceptionNO._
27import xiangshan._
28import xiangshan.backend.fu.util._
29import xiangshan.cache._
30
31// Trigger Tdata1 bundles
32trait HasTriggerConst {
33  def I_Trigger = 0.U
34  def S_Trigger = 1.U
35  def L_Trigger = 2.U
36  def GenESL(triggerType: UInt) = Cat((triggerType === I_Trigger), (triggerType === S_Trigger), (triggerType === L_Trigger))
37}
38
39class TdataBundle extends Bundle {
40  val ttype = UInt(4.W)
41  val dmode = Bool()
42  val maskmax = UInt(6.W)
43  val zero1 = UInt(30.W)
44  val sizehi = UInt(2.W)
45  val hit = Bool()
46  val select = Bool()
47  val timing = Bool()
48  val sizelo = UInt(2.W)
49  val action = UInt(4.W)
50  val chain = Bool()
51  val matchType = UInt(4.W)
52  val m = Bool()
53  val zero2 = Bool()
54  val s = Bool()
55  val u = Bool()
56  val execute = Bool()
57  val store = Bool()
58  val load = Bool()
59}
60
61class FpuCsrIO extends Bundle {
62  val fflags = Output(Valid(UInt(5.W)))
63  val isIllegal = Output(Bool())
64  val dirty_fs = Output(Bool())
65  val frm = Input(UInt(3.W))
66}
67
68
69class PerfCounterIO(implicit p: Parameters) extends XSBundle {
70  val perfEventsFrontend  = Vec(numCSRPCntFrontend, new PerfEvent)
71  val perfEventsCtrl      = Vec(numCSRPCntCtrl, new PerfEvent)
72  val perfEventsLsu       = Vec(numCSRPCntLsu, new PerfEvent)
73  val perfEventsHc        = Vec(numPCntHc * coreParams.L2NBanks, new PerfEvent)
74  val retiredInstr = UInt(3.W)
75  val frontendInfo = new Bundle {
76    val ibufFull  = Bool()
77    val bpuInfo = new Bundle {
78      val bpRight = UInt(XLEN.W)
79      val bpWrong = UInt(XLEN.W)
80    }
81  }
82  val ctrlInfo = new Bundle {
83    val robFull   = Bool()
84    val intdqFull = Bool()
85    val fpdqFull  = Bool()
86    val lsdqFull  = Bool()
87  }
88  val memInfo = new Bundle {
89    val sqFull = Bool()
90    val lqFull = Bool()
91    val dcacheMSHRFull = Bool()
92  }
93
94  val cacheInfo = new Bundle {
95    val l2MSHRFull = Bool()
96    val l3MSHRFull = Bool()
97    val l2nAcquire = UInt(XLEN.W)
98    val l2nAcquireMiss = UInt(XLEN.W)
99    val l3nAcquire = UInt(XLEN.W)
100    val l3nAcquireMiss = UInt(XLEN.W)
101  }
102}
103
104class CSRFileIO(implicit p: Parameters) extends XSBundle {
105  val hartId = Input(UInt(8.W))
106  // output (for func === CSROpType.jmp)
107  val perf = Input(new PerfCounterIO)
108  val isPerfCnt = Output(Bool())
109  // to FPU
110  val fpu = Flipped(new FpuCsrIO)
111  // from rob
112  val exception = Flipped(ValidIO(new ExceptionInfo))
113  // to ROB
114  val isXRet = Output(Bool())
115  val trapTarget = Output(UInt(VAddrBits.W))
116  val interrupt = Output(Bool())
117  val wfi_event = Output(Bool())
118  // from LSQ
119  val memExceptionVAddr = Input(UInt(VAddrBits.W))
120  // from outside cpu,externalInterrupt
121  val externalInterrupt = new ExternalInterruptIO
122  // TLB
123  val tlb = Output(new TlbCsrBundle)
124  // Debug Mode
125  // val singleStep = Output(Bool())
126  val debugMode = Output(Bool())
127  // to Fence to disable sfence
128  val disableSfence = Output(Bool())
129  // Custom microarchiture ctrl signal
130  val customCtrl = Output(new CustomCSRCtrlIO)
131  // distributed csr write
132  val distributedUpdate = Vec(2, Flipped(new DistributedCSRUpdateReq))
133}
134
135class CSR(implicit p: Parameters) extends FunctionUnit with HasCSRConst with PMPMethod with PMAMethod with HasTriggerConst
136{
137  val csrio = IO(new CSRFileIO)
138
139  val cfIn = io.in.bits.uop.cf
140  val cfOut = Wire(new CtrlFlow)
141  cfOut := cfIn
142  val flushPipe = Wire(Bool())
143
144  val (valid, src1, src2, func) = (
145    io.in.valid,
146    io.in.bits.src(0),
147    io.in.bits.uop.ctrl.imm,
148    io.in.bits.uop.ctrl.fuOpType
149  )
150
151  // CSR define
152
153  class Priv extends Bundle {
154    val m = Output(Bool())
155    val h = Output(Bool())
156    val s = Output(Bool())
157    val u = Output(Bool())
158  }
159
160  val csrNotImplemented = RegInit(UInt(XLEN.W), 0.U)
161
162  class DcsrStruct extends Bundle {
163    val xdebugver = Output(UInt(2.W))
164    val zero4 = Output(UInt(2.W))
165    val zero3 = Output(UInt(12.W))
166    val ebreakm = Output(Bool())
167    val ebreakh = Output(Bool())
168    val ebreaks = Output(Bool())
169    val ebreaku = Output(Bool())
170    val stepie = Output(Bool()) // 0
171    val stopcycle = Output(Bool())
172    val stoptime = Output(Bool())
173    val cause = Output(UInt(3.W))
174    val v = Output(Bool()) // 0
175    val mprven = Output(Bool())
176    val nmip = Output(Bool())
177    val step = Output(Bool())
178    val prv = Output(UInt(2.W))
179  }
180
181  class MstatusStruct extends Bundle {
182    val sd = Output(UInt(1.W))
183
184    val pad1 = if (XLEN == 64) Output(UInt(25.W)) else null
185    val mbe  = if (XLEN == 64) Output(UInt(1.W)) else null
186    val sbe  = if (XLEN == 64) Output(UInt(1.W)) else null
187    val sxl  = if (XLEN == 64) Output(UInt(2.W))  else null
188    val uxl  = if (XLEN == 64) Output(UInt(2.W))  else null
189    val pad0 = if (XLEN == 64) Output(UInt(9.W))  else Output(UInt(8.W))
190
191    val tsr = Output(UInt(1.W))
192    val tw = Output(UInt(1.W))
193    val tvm = Output(UInt(1.W))
194    val mxr = Output(UInt(1.W))
195    val sum = Output(UInt(1.W))
196    val mprv = Output(UInt(1.W))
197    val xs = Output(UInt(2.W))
198    val fs = Output(UInt(2.W))
199    val mpp = Output(UInt(2.W))
200    val hpp = Output(UInt(2.W))
201    val spp = Output(UInt(1.W))
202    val pie = new Priv
203    val ie = new Priv
204    assert(this.getWidth == XLEN)
205
206    def ube = pie.h // a little ugly
207    def ube_(r: UInt): Unit = {
208      pie.h := r(0)
209    }
210  }
211
212  class Interrupt extends Bundle {
213//  val d = Output(Bool())    // Debug
214    val e = new Priv
215    val t = new Priv
216    val s = new Priv
217  }
218
219  // Debug CSRs
220  val dcsr = RegInit(UInt(32.W), 0x4000b000.U)
221  val dpc = Reg(UInt(64.W))
222  val dscratch = Reg(UInt(64.W))
223  val dscratch1 = Reg(UInt(64.W))
224  val debugMode = RegInit(false.B)
225  val debugIntrEnable = RegInit(true.B)
226  csrio.debugMode := debugMode
227
228  val dpcPrev = RegNext(dpc)
229  XSDebug(dpcPrev =/= dpc, "Debug Mode: dpc is altered! Current is %x, previous is %x\n", dpc, dpcPrev)
230
231  // dcsr value table
232  // | debugver | 0100
233  // | zero     | 10 bits of 0
234  // | ebreakvs | 0
235  // | ebreakvu | 0
236  // | ebreakm  | 1 if ebreak enters debug
237  // | zero     | 0
238  // | ebreaks  |
239  // | ebreaku  |
240  // | stepie   | disable interrupts in singlestep
241  // | stopcount| stop counter, 0
242  // | stoptime | stop time, 0
243  // | cause    | 3 bits read only
244  // | v        | 0
245  // | mprven   | 1
246  // | nmip     | read only
247  // | step     |
248  // | prv      | 2 bits
249
250  val dcsrData = Wire(new DcsrStruct)
251  dcsrData := dcsr.asTypeOf(new DcsrStruct)
252  val dcsrMask = ZeroExt(GenMask(15) | GenMask(13, 11) | GenMask(4) | GenMask(2, 0), XLEN)// Dcsr write mask
253  def dcsrUpdateSideEffect(dcsr: UInt): UInt = {
254    val dcsrOld = WireInit(dcsr.asTypeOf(new DcsrStruct))
255    val dcsrNew = dcsr | (dcsrOld.prv(0) | dcsrOld.prv(1)).asUInt // turn 10 priv into 11
256    dcsrNew
257  }
258  // csrio.singleStep := dcsrData.step
259  csrio.customCtrl.singlestep := dcsrData.step && !debugMode
260
261  // Trigger CSRs
262
263  val type_config = Array(
264    0.U -> I_Trigger, 1.U -> I_Trigger,
265    2.U -> S_Trigger, 3.U -> S_Trigger,
266    4.U -> L_Trigger, 5.U -> L_Trigger, // No.5 Load Trigger
267    6.U -> I_Trigger, 7.U -> S_Trigger,
268    8.U -> I_Trigger, 9.U -> L_Trigger
269  )
270  def TypeLookup(select: UInt) = MuxLookup(select, I_Trigger, type_config)
271
272  val tdata1Phy = RegInit(VecInit(List.fill(10) {(2L << 60L).U(64.W)})) // init ttype 2
273  val tdata2Phy = Reg(Vec(10, UInt(64.W)))
274  val tselectPhy = RegInit(0.U(4.W))
275  val tinfo = RegInit(2.U(64.W))
276  val tControlPhy = RegInit(0.U(64.W))
277  val triggerAction = RegInit(false.B)
278
279  def ReadTdata1(rdata: UInt) = rdata | Cat(triggerAction, 0.U(12.W)) // fix action
280  def WriteTdata1(wdata: UInt): UInt = {
281    val tdata1 = WireInit(tdata1Phy(tselectPhy).asTypeOf(new TdataBundle))
282    val wdata_wire = WireInit(wdata.asTypeOf(new TdataBundle))
283    val tdata1_new = WireInit(wdata.asTypeOf(new TdataBundle))
284    XSDebug(src2(11, 0) === Tdata1.U && valid && func =/= CSROpType.jmp, p"Debug Mode: tdata1(${tselectPhy})is written, the actual value is ${wdata}\n")
285//    tdata1_new.hit := wdata(20)
286    tdata1_new.ttype := tdata1.ttype
287    tdata1_new.dmode := 0.U // Mux(debugMode, wdata_wire.dmode, tdata1.dmode)
288    tdata1_new.maskmax := 0.U
289    tdata1_new.hit := 0.U
290    tdata1_new.select := (TypeLookup(tselectPhy) === I_Trigger) && wdata_wire.select
291    when(wdata_wire.action <= 1.U){
292      triggerAction := tdata1_new.action(0)
293    } .otherwise{
294      tdata1_new.action := tdata1.action
295    }
296    tdata1_new.timing := false.B // hardwire this because we have singlestep
297    tdata1_new.zero1 := 0.U
298    tdata1_new.zero2 := 0.U
299    tdata1_new.chain := !tselectPhy(0) && wdata_wire.chain
300    when(wdata_wire.matchType =/= 0.U && wdata_wire.matchType =/= 2.U && wdata_wire.matchType =/= 3.U) {
301      tdata1_new.matchType := tdata1.matchType
302    }
303    tdata1_new.sizehi := Mux(wdata_wire.select && TypeLookup(tselectPhy) === I_Trigger, 0.U, 1.U)
304    tdata1_new.sizelo:= Mux(wdata_wire.select && TypeLookup(tselectPhy) === I_Trigger, 3.U, 1.U)
305    tdata1_new.execute := TypeLookup(tselectPhy) === I_Trigger
306    tdata1_new.store := TypeLookup(tselectPhy) === S_Trigger
307    tdata1_new.load := TypeLookup(tselectPhy) === L_Trigger
308    tdata1_new.asUInt
309  }
310
311  def WriteTselect(wdata: UInt) = {
312    Mux(wdata < 10.U, wdata(3, 0), tselectPhy)
313  }
314
315  val tcontrolWriteMask = ZeroExt(GenMask(3) | GenMask(7), XLEN)
316
317
318  def GenTdataDistribute(tdata1: TdataBundle, tdata2: UInt): MatchTriggerIO = {
319    val res = Wire(new MatchTriggerIO)
320    res.matchType := tdata1.matchType
321    res.select := tdata1.select
322    res.timing := tdata1.timing
323    res.action := triggerAction
324    res.chain := tdata1.chain
325    res.tdata2 := tdata2
326    res
327  }
328
329  csrio.customCtrl.frontend_trigger.t.bits.addr := MuxLookup(tselectPhy, 0.U, Seq(
330    0.U -> 0.U,
331    1.U -> 1.U,
332    6.U -> 2.U,
333    8.U -> 3.U
334  ))
335  csrio.customCtrl.mem_trigger.t.bits.addr := MuxLookup(tselectPhy, 0.U, Seq(
336    2.U -> 0.U,
337    3.U -> 1.U,
338    4.U -> 2.U,
339    5.U -> 3.U,
340    7.U -> 4.U,
341    9.U -> 5.U
342  ))
343  csrio.customCtrl.frontend_trigger.t.bits.tdata := GenTdataDistribute(tdata1Phy(tselectPhy).asTypeOf(new TdataBundle), tdata2Phy(tselectPhy))
344  csrio.customCtrl.mem_trigger.t.bits.tdata := GenTdataDistribute(tdata1Phy(tselectPhy).asTypeOf(new TdataBundle), tdata2Phy(tselectPhy))
345
346  // Machine-Level CSRs
347  // mtvec: {BASE (WARL), MODE (WARL)} where mode is 0 or 1
348  val mtvecMask = ~(0x2.U(XLEN.W))
349  val mtvec = RegInit(UInt(XLEN.W), 0.U)
350  val mcounteren = RegInit(UInt(XLEN.W), 0.U)
351  val mcause = RegInit(UInt(XLEN.W), 0.U)
352  val mtval = RegInit(UInt(XLEN.W), 0.U)
353  val mepc = Reg(UInt(XLEN.W))
354  // Page 36 in riscv-priv: The low bit of mepc (mepc[0]) is always zero.
355  val mepcMask = ~(0x1.U(XLEN.W))
356
357  val mie = RegInit(0.U(XLEN.W))
358  val mipWire = WireInit(0.U.asTypeOf(new Interrupt))
359  val mipReg  = RegInit(0.U(XLEN.W))
360  val mipFixMask = ZeroExt(GenMask(9) | GenMask(5) | GenMask(1), XLEN)
361  val mip = (mipWire.asUInt | mipReg).asTypeOf(new Interrupt)
362
363  def getMisaMxl(mxl: Int): UInt = {mxl.U << (XLEN-2)}.asUInt
364  def getMisaExt(ext: Char): UInt = {1.U << (ext.toInt - 'a'.toInt)}.asUInt
365  var extList = List('a', 's', 'i', 'u')
366  if (HasMExtension) { extList = extList :+ 'm' }
367  if (HasCExtension) { extList = extList :+ 'c' }
368  if (HasFPU) { extList = extList ++ List('f', 'd') }
369  val misaInitVal = getMisaMxl(2) | extList.foldLeft(0.U)((sum, i) => sum | getMisaExt(i)) //"h8000000000141105".U
370  val misa = RegInit(UInt(XLEN.W), misaInitVal)
371
372  // MXL = 2          | 0 | EXT = b 00 0000 0100 0001 0001 0000 0101
373  // (XLEN-1, XLEN-2) |   |(25, 0)  ZY XWVU TSRQ PONM LKJI HGFE DCBA
374
375  val mvendorid = RegInit(UInt(XLEN.W), 0.U) // this is a non-commercial implementation
376  val marchid = RegInit(UInt(XLEN.W), 25.U) // architecture id for XiangShan is 25; see https://github.com/riscv/riscv-isa-manual/blob/master/marchid.md
377  val mimpid = RegInit(UInt(XLEN.W), 0.U) // provides a unique encoding of the version of the processor implementation
378  val mhartid = RegInit(UInt(XLEN.W), csrio.hartId) // the hardware thread running the code
379  val mconfigptr = RegInit(UInt(XLEN.W), 0.U) // the read-only pointer pointing to the platform config structure, 0 for not supported.
380  val mstatus = RegInit("ha00002000".U(XLEN.W))
381
382  // mstatus Value Table
383  // | sd   |
384  // | pad1 |
385  // | sxl  | hardlinked to 10, use 00 to pass xv6 test
386  // | uxl  | hardlinked to 10
387  // | pad0 |
388  // | tsr  |
389  // | tw   |
390  // | tvm  |
391  // | mxr  |
392  // | sum  |
393  // | mprv |
394  // | xs   | 00 |
395  // | fs   | 01 |
396  // | mpp  | 00 |
397  // | hpp  | 00 |
398  // | spp  | 0 |
399  // | pie  | 0000 | pie.h is used as UBE
400  // | ie   | 0000 | uie hardlinked to 0, as N ext is not implemented
401
402  val mstatusStruct = mstatus.asTypeOf(new MstatusStruct)
403  def mstatusUpdateSideEffect(mstatus: UInt): UInt = {
404    val mstatusOld = WireInit(mstatus.asTypeOf(new MstatusStruct))
405    val mstatusNew = Cat(mstatusOld.xs === "b11".U || mstatusOld.fs === "b11".U, mstatus(XLEN-2, 0))
406    mstatusNew
407  }
408
409  val mstatusWMask = (~ZeroExt((
410    GenMask(XLEN - 2, 36) | // WPRI
411    GenMask(35, 32)       | // SXL and UXL cannot be changed
412    GenMask(31, 23)       | // WPRI
413    GenMask(16, 15)       | // XS is read-only
414    GenMask(10, 9)        | // WPRI
415    GenMask(6)            | // WPRI
416    GenMask(2)              // WPRI
417  ), 64)).asUInt
418  val mstatusMask = (~ZeroExt((
419    GenMask(XLEN - 2, 36) | // WPRI
420    GenMask(31, 23)       | // WPRI
421    GenMask(10, 9)        | // WPRI
422    GenMask(6)            | // WPRI
423    GenMask(2)              // WPRI
424  ), 64)).asUInt
425
426  val medeleg = RegInit(UInt(XLEN.W), 0.U)
427  val mideleg = RegInit(UInt(XLEN.W), 0.U)
428  val mscratch = RegInit(UInt(XLEN.W), 0.U)
429
430  // PMP Mapping
431  val pmp = Wire(Vec(NumPMP, new PMPEntry())) // just used for method parameter
432  val pma = Wire(Vec(NumPMA, new PMPEntry())) // just used for method parameter
433  val pmpMapping = pmp_gen_mapping(pmp_init, NumPMP, PmpcfgBase, PmpaddrBase, pmp)
434  val pmaMapping = pmp_gen_mapping(pma_init, NumPMA, PmacfgBase, PmaaddrBase, pma)
435
436  // Superviser-Level CSRs
437
438  // val sstatus = RegInit(UInt(XLEN.W), "h00000000".U)
439  val sstatusWmask = "hc6122".U(XLEN.W)
440  // Sstatus Write Mask
441  // -------------------------------------------------------
442  //    19           9   5     2
443  // 0  1100 0000 0001 0010 0010
444  // 0  c    0    1    2    2
445  // -------------------------------------------------------
446  val sstatusRmask = sstatusWmask | "h8000000300018000".U
447  // Sstatus Read Mask = (SSTATUS_WMASK | (0xf << 13) | (1ull << 63) | (3ull << 32))
448  // stvec: {BASE (WARL), MODE (WARL)} where mode is 0 or 1
449  val stvecMask = ~(0x2.U(XLEN.W))
450  val stvec = RegInit(UInt(XLEN.W), 0.U)
451  // val sie = RegInit(0.U(XLEN.W))
452  val sieMask = "h222".U & mideleg
453  val sipMask = "h222".U & mideleg
454  val sipWMask = "h2".U(XLEN.W) // ssip is writeable in smode
455  val satp = if(EnbaleTlbDebug) RegInit(UInt(XLEN.W), "h8000000000087fbe".U) else RegInit(0.U(XLEN.W))
456  // val satp = RegInit(UInt(XLEN.W), "h8000000000087fbe".U) // only use for tlb naive debug
457  // val satpMask = "h80000fffffffffff".U(XLEN.W) // disable asid, mode can only be 8 / 0
458  // TODO: use config to control the length of asid
459  // val satpMask = "h8fffffffffffffff".U(XLEN.W) // enable asid, mode can only be 8 / 0
460  val satpMask = Cat("h8".U(Satp_Mode_len.W), satp_part_wmask(Satp_Asid_len, AsidLength), satp_part_wmask(Satp_Addr_len, PAddrBits-12))
461  val sepc = RegInit(UInt(XLEN.W), 0.U)
462  // Page 60 in riscv-priv: The low bit of sepc (sepc[0]) is always zero.
463  val sepcMask = ~(0x1.U(XLEN.W))
464  val scause = RegInit(UInt(XLEN.W), 0.U)
465  val stval = Reg(UInt(XLEN.W))
466  val sscratch = RegInit(UInt(XLEN.W), 0.U)
467  val scounteren = RegInit(UInt(XLEN.W), 0.U)
468
469  // sbpctl
470  // Bits 0-7: {LOOP, RAS, SC, TAGE, BIM, BTB, uBTB}
471  val sbpctl = RegInit(UInt(XLEN.W), "h7f".U)
472  csrio.customCtrl.bp_ctrl.ubtb_enable := sbpctl(0)
473  csrio.customCtrl.bp_ctrl.btb_enable  := sbpctl(1)
474  csrio.customCtrl.bp_ctrl.bim_enable  := sbpctl(2)
475  csrio.customCtrl.bp_ctrl.tage_enable := sbpctl(3)
476  csrio.customCtrl.bp_ctrl.sc_enable   := sbpctl(4)
477  csrio.customCtrl.bp_ctrl.ras_enable  := sbpctl(5)
478  csrio.customCtrl.bp_ctrl.loop_enable := sbpctl(6)
479
480  // spfctl Bit 0: L1I Cache Prefetcher Enable
481  // spfctl Bit 1: L2Cache Prefetcher Enable
482  val spfctl = RegInit(UInt(XLEN.W), "b11".U)
483  csrio.customCtrl.l1I_pf_enable := spfctl(0)
484  csrio.customCtrl.l2_pf_enable := spfctl(1)
485
486  // sfetchctl Bit 0: L1I Cache Parity check enable
487  val sfetchctl = RegInit(UInt(XLEN.W), "b0".U)
488  csrio.customCtrl.icache_parity_enable := sfetchctl(0)
489
490  // sdsid: Differentiated Services ID
491  val sdsid = RegInit(UInt(XLEN.W), 0.U)
492  csrio.customCtrl.dsid := sdsid
493
494  // slvpredctl: load violation predict settings
495  // Default reset period: 2^16
496  // Why this number: reset more frequently while keeping the overhead low
497  // Overhead: extra two redirections in every 64K cycles => ~0.1% overhead
498  val slvpredctl = RegInit(UInt(XLEN.W), "h60".U)
499  csrio.customCtrl.lvpred_disable := slvpredctl(0)
500  csrio.customCtrl.no_spec_load := slvpredctl(1)
501  csrio.customCtrl.storeset_wait_store := slvpredctl(2)
502  csrio.customCtrl.storeset_no_fast_wakeup := slvpredctl(3)
503  csrio.customCtrl.lvpred_timeout := slvpredctl(8, 4)
504
505  // smblockctl: memory block configurations
506  // bits 0-3: store buffer flush threshold (default: 8 entries)
507  val smblockctl_init_val =
508    ("hf".U & StoreBufferThreshold.U) |
509    (EnableLdVioCheckAfterReset.B.asUInt << 4) |
510    (EnableSoftPrefetchAfterReset.B.asUInt << 5) |
511    (EnableCacheErrorAfterReset.B.asUInt << 6)
512  val smblockctl = RegInit(UInt(XLEN.W), smblockctl_init_val)
513  csrio.customCtrl.sbuffer_threshold := smblockctl(3, 0)
514  // bits 4: enable load load violation check
515  csrio.customCtrl.ldld_vio_check_enable := smblockctl(4)
516  csrio.customCtrl.soft_prefetch_enable := smblockctl(5)
517  csrio.customCtrl.cache_error_enable := smblockctl(6)
518
519  println("CSR smblockctl init value:")
520  println("  Store buffer replace threshold: " + StoreBufferThreshold)
521  println("  Enable ld-ld vio check after reset: " + EnableLdVioCheckAfterReset)
522  println("  Enable soft prefetch after reset: " + EnableSoftPrefetchAfterReset)
523  println("  Enable cache error after reset: " + EnableCacheErrorAfterReset)
524
525  val srnctl = RegInit(UInt(XLEN.W), "h3".U)
526  csrio.customCtrl.move_elim_enable := srnctl(0)
527  csrio.customCtrl.svinval_enable := srnctl(1)
528
529  val tlbBundle = Wire(new TlbCsrBundle)
530  tlbBundle.satp.apply(satp)
531
532  csrio.tlb := tlbBundle
533
534  // User-Level CSRs
535  val uepc = Reg(UInt(XLEN.W))
536
537  // fcsr
538  class FcsrStruct extends Bundle {
539    val reserved = UInt((XLEN-3-5).W)
540    val frm = UInt(3.W)
541    val fflags = UInt(5.W)
542    assert(this.getWidth == XLEN)
543  }
544  val fcsr = RegInit(0.U(XLEN.W))
545  // set mstatus->sd and mstatus->fs when true
546  val csrw_dirty_fp_state = WireInit(false.B)
547
548  def frm_wfn(wdata: UInt): UInt = {
549    val fcsrOld = WireInit(fcsr.asTypeOf(new FcsrStruct))
550    csrw_dirty_fp_state := true.B
551    fcsrOld.frm := wdata(2,0)
552    fcsrOld.asUInt
553  }
554  def frm_rfn(rdata: UInt): UInt = rdata(7,5)
555
556  def fflags_wfn(update: Boolean)(wdata: UInt): UInt = {
557    val fcsrOld = fcsr.asTypeOf(new FcsrStruct)
558    val fcsrNew = WireInit(fcsrOld)
559    csrw_dirty_fp_state := true.B
560    if (update) {
561      fcsrNew.fflags := wdata(4,0) | fcsrOld.fflags
562    } else {
563      fcsrNew.fflags := wdata(4,0)
564    }
565    fcsrNew.asUInt
566  }
567  def fflags_rfn(rdata:UInt): UInt = rdata(4,0)
568
569  def fcsr_wfn(wdata: UInt): UInt = {
570    val fcsrOld = WireInit(fcsr.asTypeOf(new FcsrStruct))
571    csrw_dirty_fp_state := true.B
572    Cat(fcsrOld.reserved, wdata.asTypeOf(fcsrOld).frm, wdata.asTypeOf(fcsrOld).fflags)
573  }
574
575  val fcsrMapping = Map(
576    MaskedRegMap(Fflags, fcsr, wfn = fflags_wfn(update = false), rfn = fflags_rfn),
577    MaskedRegMap(Frm, fcsr, wfn = frm_wfn, rfn = frm_rfn),
578    MaskedRegMap(Fcsr, fcsr, wfn = fcsr_wfn)
579  )
580
581  // Hart Priviledge Mode
582  val priviledgeMode = RegInit(UInt(2.W), ModeM)
583
584  //val perfEventscounten = List.fill(nrPerfCnts)(RegInit(false(Bool())))
585  // Perf Counter
586  val nrPerfCnts = 29  // 3...31
587  val priviledgeModeOH = UIntToOH(priviledgeMode)
588  val perfEventscounten = RegInit(0.U.asTypeOf(Vec(nrPerfCnts, Bool())))
589  val perfCnts   = List.fill(nrPerfCnts)(RegInit(0.U(XLEN.W)))
590  val perfEvents = List.fill(8)(RegInit("h0000000000".U(XLEN.W))) ++
591                   List.fill(8)(RegInit("h4010040100".U(XLEN.W))) ++
592                   List.fill(8)(RegInit("h8020080200".U(XLEN.W))) ++
593                   List.fill(5)(RegInit("hc0300c0300".U(XLEN.W)))
594  for (i <-0 until nrPerfCnts) {
595    perfEventscounten(i) := (Cat(perfEvents(i)(62),perfEvents(i)(61),(perfEvents(i)(61,60))) & priviledgeModeOH).orR
596  }
597
598  val hpmEvents = Wire(Vec(numPCntHc * coreParams.L2NBanks, new PerfEvent))
599  for (i <- 0 until numPCntHc * coreParams.L2NBanks) {
600    hpmEvents(i) := csrio.perf.perfEventsHc(i)
601  }
602
603  val csrevents = perfEvents.slice(24, 29)
604  val hpm_hc = HPerfMonitor(csrevents, hpmEvents)
605  val mcountinhibit = RegInit(0.U(XLEN.W))
606  val mcycle = RegInit(0.U(XLEN.W))
607  mcycle := mcycle + 1.U
608  val minstret = RegInit(0.U(XLEN.W))
609  val perf_events = csrio.perf.perfEventsFrontend ++
610                    csrio.perf.perfEventsCtrl ++
611                    csrio.perf.perfEventsLsu ++
612                    hpm_hc.getPerf
613  minstret := minstret + RegNext(csrio.perf.retiredInstr)
614  for(i <- 0 until 29){
615    perfCnts(i) := Mux(mcountinhibit(i+3) | !perfEventscounten(i), perfCnts(i), perfCnts(i) + perf_events(i).value)
616  }
617
618  // CSR reg map
619  val basicPrivMapping = Map(
620
621    //--- User Trap Setup ---
622    // MaskedRegMap(Ustatus, ustatus),
623    // MaskedRegMap(Uie, uie, 0.U, MaskedRegMap.Unwritable),
624    // MaskedRegMap(Utvec, utvec),
625
626    //--- User Trap Handling ---
627    // MaskedRegMap(Uscratch, uscratch),
628    // MaskedRegMap(Uepc, uepc),
629    // MaskedRegMap(Ucause, ucause),
630    // MaskedRegMap(Utval, utval),
631    // MaskedRegMap(Uip, uip),
632
633    //--- User Counter/Timers ---
634    // MaskedRegMap(Cycle, cycle),
635    // MaskedRegMap(Time, time),
636    // MaskedRegMap(Instret, instret),
637
638    //--- Supervisor Trap Setup ---
639    MaskedRegMap(Sstatus, mstatus, sstatusWmask, mstatusUpdateSideEffect, sstatusRmask),
640    // MaskedRegMap(Sedeleg, Sedeleg),
641    // MaskedRegMap(Sideleg, Sideleg),
642    MaskedRegMap(Sie, mie, sieMask, MaskedRegMap.NoSideEffect, sieMask),
643    MaskedRegMap(Stvec, stvec, stvecMask, MaskedRegMap.NoSideEffect, stvecMask),
644    MaskedRegMap(Scounteren, scounteren),
645
646    //--- Supervisor Trap Handling ---
647    MaskedRegMap(Sscratch, sscratch),
648    MaskedRegMap(Sepc, sepc, sepcMask, MaskedRegMap.NoSideEffect, sepcMask),
649    MaskedRegMap(Scause, scause),
650    MaskedRegMap(Stval, stval),
651    MaskedRegMap(Sip, mip.asUInt, sipWMask, MaskedRegMap.Unwritable, sipMask),
652
653    //--- Supervisor Protection and Translation ---
654    MaskedRegMap(Satp, satp, satpMask, MaskedRegMap.NoSideEffect, satpMask),
655
656    //--- Supervisor Custom Read/Write Registers
657    MaskedRegMap(Sbpctl, sbpctl),
658    MaskedRegMap(Spfctl, spfctl),
659    MaskedRegMap(Sfetchctl, sfetchctl),
660    MaskedRegMap(Sdsid, sdsid),
661    MaskedRegMap(Slvpredctl, slvpredctl),
662    MaskedRegMap(Smblockctl, smblockctl),
663    MaskedRegMap(Srnctl, srnctl),
664
665    //--- Machine Information Registers ---
666    MaskedRegMap(Mvendorid, mvendorid, 0.U(XLEN.W), MaskedRegMap.Unwritable),
667    MaskedRegMap(Marchid, marchid, 0.U(XLEN.W), MaskedRegMap.Unwritable),
668    MaskedRegMap(Mimpid, mimpid, 0.U(XLEN.W), MaskedRegMap.Unwritable),
669    MaskedRegMap(Mhartid, mhartid, 0.U(XLEN.W), MaskedRegMap.Unwritable),
670    MaskedRegMap(Mconfigptr, mconfigptr, 0.U(XLEN.W), MaskedRegMap.Unwritable),
671
672    //--- Machine Trap Setup ---
673    MaskedRegMap(Mstatus, mstatus, mstatusWMask, mstatusUpdateSideEffect, mstatusMask),
674    MaskedRegMap(Misa, misa), // now MXL, EXT is not changeable
675    MaskedRegMap(Medeleg, medeleg, "hf3ff".U(XLEN.W)),
676    MaskedRegMap(Mideleg, mideleg, "h222".U(XLEN.W)),
677    MaskedRegMap(Mie, mie),
678    MaskedRegMap(Mtvec, mtvec, mtvecMask, MaskedRegMap.NoSideEffect, mtvecMask),
679    MaskedRegMap(Mcounteren, mcounteren),
680
681    //--- Machine Trap Handling ---
682    MaskedRegMap(Mscratch, mscratch),
683    MaskedRegMap(Mepc, mepc, mepcMask, MaskedRegMap.NoSideEffect, mepcMask),
684    MaskedRegMap(Mcause, mcause),
685    MaskedRegMap(Mtval, mtval),
686    MaskedRegMap(Mip, mip.asUInt, 0.U(XLEN.W), MaskedRegMap.Unwritable),
687
688    //--- Trigger ---
689    MaskedRegMap(Tselect, tselectPhy, WritableMask, WriteTselect),
690    MaskedRegMap(Tdata1, tdata1Phy(tselectPhy), WritableMask, WriteTdata1, WritableMask, ReadTdata1),
691    MaskedRegMap(Tdata2, tdata2Phy(tselectPhy)),
692    MaskedRegMap(Tinfo, tinfo, 0.U(XLEN.W), MaskedRegMap.Unwritable),
693    MaskedRegMap(Tcontrol, tControlPhy, tcontrolWriteMask),
694
695    //--- Debug Mode ---
696    MaskedRegMap(Dcsr, dcsr, dcsrMask, dcsrUpdateSideEffect),
697    MaskedRegMap(Dpc, dpc),
698    MaskedRegMap(Dscratch, dscratch),
699    MaskedRegMap(Dscratch1, dscratch1),
700    MaskedRegMap(Mcountinhibit, mcountinhibit),
701    MaskedRegMap(Mcycle, mcycle),
702    MaskedRegMap(Minstret, minstret),
703  )
704
705  val perfCntMapping = (0 until 29).map(i => {Map(
706    MaskedRegMap(addr = Mhpmevent3 +i,
707                 reg  = perfEvents(i),
708                 wmask = "hf87fff3fcff3fcff".U(XLEN.W)),
709    MaskedRegMap(addr = Mhpmcounter3 +i,
710                 reg  = perfCnts(i))
711  )}).fold(Map())((a,b) => a ++ b)
712  // TODO: mechanism should be implemented later
713  // val MhpmcounterStart = Mhpmcounter3
714  // val MhpmeventStart   = Mhpmevent3
715  // for (i <- 0 until nrPerfCnts) {
716  //   perfCntMapping += MaskedRegMap(MhpmcounterStart + i, perfCnts(i))
717  //   perfCntMapping += MaskedRegMap(MhpmeventStart + i, perfEvents(i))
718  // }
719
720  val cacheopRegs = CacheInstrucion.CacheInsRegisterList.map{case (name, attribute) => {
721    name -> RegInit(0.U(attribute("width").toInt.W))
722  }}
723  val cacheopMapping = CacheInstrucion.CacheInsRegisterList.map{case (name, attribute) => {
724    MaskedRegMap(
725      Scachebase + attribute("offset").toInt,
726      cacheopRegs(name)
727    )
728  }}
729
730  val mapping = basicPrivMapping ++
731                perfCntMapping ++
732                pmpMapping ++
733                pmaMapping ++
734                (if (HasFPU) fcsrMapping else Nil) ++
735                (if (HasCustomCSRCacheOp) cacheopMapping else Nil)
736
737  val addr = src2(11, 0)
738  val csri = ZeroExt(src2(16, 12), XLEN)
739  val rdata = Wire(UInt(XLEN.W))
740  val wdata = LookupTree(func, List(
741    CSROpType.wrt  -> src1,
742    CSROpType.set  -> (rdata | src1),
743    CSROpType.clr  -> (rdata & (~src1).asUInt),
744    CSROpType.wrti -> csri,
745    CSROpType.seti -> (rdata | csri),
746    CSROpType.clri -> (rdata & (~csri).asUInt)
747  ))
748
749  val addrInPerfCnt = (addr >= Mcycle.U) && (addr <= Mhpmcounter31.U) ||
750    (addr >= Mcountinhibit.U) && (addr <= Mhpmevent31.U) ||
751    addr === Mip.U
752  csrio.isPerfCnt := addrInPerfCnt && valid && func =/= CSROpType.jmp
753
754  // satp wen check
755  val satpLegalMode = (wdata.asTypeOf(new SatpStruct).mode===0.U) || (wdata.asTypeOf(new SatpStruct).mode===8.U)
756
757  // csr access check, special case
758  val tvmNotPermit = (priviledgeMode === ModeS && mstatusStruct.tvm.asBool)
759  val accessPermitted = !(addr === Satp.U && tvmNotPermit)
760  csrio.disableSfence := tvmNotPermit
761
762  // general CSR wen check
763  val wen = valid && func =/= CSROpType.jmp && (addr=/=Satp.U || satpLegalMode)
764  val dcsrPermitted = dcsrPermissionCheck(addr, false.B, debugMode)
765  val triggerPermitted = triggerPermissionCheck(addr, true.B, debugMode) // todo dmode
766  val modePermitted = csrAccessPermissionCheck(addr, false.B, priviledgeMode) && dcsrPermitted && triggerPermitted
767  val perfcntPermitted = perfcntPermissionCheck(addr, priviledgeMode, mcounteren, scounteren)
768  val permitted = Mux(addrInPerfCnt, perfcntPermitted, modePermitted) && accessPermitted
769
770  MaskedRegMap.generate(mapping, addr, rdata, wen && permitted, wdata)
771  io.out.bits.data := rdata
772  io.out.bits.uop := io.in.bits.uop
773  io.out.bits.uop.cf := cfOut
774  io.out.bits.uop.ctrl.flushPipe := flushPipe
775
776  // send distribute csr a w signal
777  csrio.customCtrl.distribute_csr.w.valid := wen && permitted
778  csrio.customCtrl.distribute_csr.w.bits.data := wdata
779  csrio.customCtrl.distribute_csr.w.bits.addr := addr
780
781  // Fix Mip/Sip write
782  val fixMapping = Map(
783    MaskedRegMap(Mip, mipReg.asUInt, mipFixMask),
784    MaskedRegMap(Sip, mipReg.asUInt, sipWMask, MaskedRegMap.NoSideEffect, sipMask)
785  )
786  val rdataFix = Wire(UInt(XLEN.W))
787  val wdataFix = LookupTree(func, List(
788    CSROpType.wrt  -> src1,
789    CSROpType.set  -> (rdataFix | src1),
790    CSROpType.clr  -> (rdataFix & (~src1).asUInt),
791    CSROpType.wrti -> csri,
792    CSROpType.seti -> (rdataFix | csri),
793    CSROpType.clri -> (rdataFix & (~csri).asUInt)
794  ))
795  MaskedRegMap.generate(fixMapping, addr, rdataFix, wen && permitted, wdataFix)
796
797  when (RegNext(csrio.fpu.fflags.valid)) {
798    fcsr := fflags_wfn(update = true)(RegNext(csrio.fpu.fflags.bits))
799  }
800  // set fs and sd in mstatus
801  when (csrw_dirty_fp_state || RegNext(csrio.fpu.dirty_fs)) {
802    val mstatusNew = WireInit(mstatus.asTypeOf(new MstatusStruct))
803    mstatusNew.fs := "b11".U
804    mstatusNew.sd := true.B
805    mstatus := mstatusNew.asUInt
806  }
807  csrio.fpu.frm := fcsr.asTypeOf(new FcsrStruct).frm
808
809
810  // Trigger Ctrl
811  csrio.customCtrl.trigger_enable := tdata1Phy.map{t =>
812    def tdata1 = t.asTypeOf(new TdataBundle)
813    tdata1.m && priviledgeMode === ModeM ||
814    tdata1.s && priviledgeMode === ModeS || tdata1.u && priviledgeMode === ModeU
815  }
816  csrio.customCtrl.frontend_trigger.t.valid := RegNext(wen && (addr === Tdata1.U || addr === Tdata2.U) && TypeLookup(tselectPhy) === I_Trigger)
817  csrio.customCtrl.mem_trigger.t.valid := RegNext(wen && (addr === Tdata1.U || addr === Tdata2.U) && TypeLookup(tselectPhy) =/= I_Trigger)
818  XSDebug(csrio.customCtrl.trigger_enable.asUInt.orR, p"Debug Mode: At least 1 trigger is enabled," +
819    p"trigger enable is ${Binary(csrio.customCtrl.trigger_enable.asUInt)}\n")
820
821  // CSR inst decode
822  val isEbreak = addr === privEbreak && func === CSROpType.jmp
823  val isEcall  = addr === privEcall  && func === CSROpType.jmp
824  val isMret   = addr === privMret   && func === CSROpType.jmp
825  val isSret   = addr === privSret   && func === CSROpType.jmp
826  val isUret   = addr === privUret   && func === CSROpType.jmp
827  val isDret   = addr === privDret   && func === CSROpType.jmp
828  val isWFI    = func === CSROpType.wfi
829
830  XSDebug(wen, "csr write: pc %x addr %x rdata %x wdata %x func %x\n", cfIn.pc, addr, rdata, wdata, func)
831  XSDebug(wen, "pc %x mstatus %x mideleg %x medeleg %x mode %x\n", cfIn.pc, mstatus, mideleg , medeleg, priviledgeMode)
832
833  // Illegal priviledged operation list
834  val illegalMret = valid && isMret && priviledgeMode < ModeM
835  val illegalSret = valid && isSret && priviledgeMode < ModeS
836  val illegalSModeSret = valid && isSret && priviledgeMode === ModeS && mstatusStruct.tsr.asBool
837  // When TW=1, then if WFI is executed in any less-privileged mode,
838  // and it does not complete within an implementation-specific, bounded time limit,
839  // the WFI instruction causes an illegal instruction exception.
840  // The time limit may always be 0, in which case WFI always causes
841  // an illegal instruction exception in less-privileged modes when TW=1.
842  val illegalWFI = valid && isWFI && priviledgeMode < ModeM && mstatusStruct.tw === 1.U
843
844  // Illegal priviledged instruction check
845  val isIllegalAddr = valid && CSROpType.needAccess(func) && MaskedRegMap.isIllegalAddr(mapping, addr)
846  val isIllegalAccess = wen && !permitted
847  val isIllegalPrivOp = illegalMret || illegalSret || illegalSModeSret || illegalWFI
848
849  // expose several csr bits for tlb
850  tlbBundle.priv.mxr   := mstatusStruct.mxr.asBool
851  tlbBundle.priv.sum   := mstatusStruct.sum.asBool
852  tlbBundle.priv.imode := priviledgeMode
853  tlbBundle.priv.dmode := Mux(debugMode && dcsr.asTypeOf(new DcsrStruct).mprven, ModeM, Mux(mstatusStruct.mprv.asBool, mstatusStruct.mpp, priviledgeMode))
854
855  // Branch control
856  val retTarget = Wire(UInt(VAddrBits.W))
857  val resetSatp = addr === Satp.U && wen // write to satp will cause the pipeline be flushed
858  flushPipe := resetSatp || (valid && func === CSROpType.jmp && !isEcall && !isEbreak)
859
860  retTarget := DontCare
861  // val illegalEret = TODO
862
863  when (valid && isDret) {
864    val mstatusOld = WireInit(mstatus.asTypeOf(new MstatusStruct))
865    val mstatusNew = WireInit(mstatus.asTypeOf(new MstatusStruct))
866    val dcsrNew = WireInit(dcsr.asTypeOf(new DcsrStruct))
867    val debugModeNew = WireInit(debugMode)
868    when (dcsr.asTypeOf(new DcsrStruct).prv =/= ModeM) {mstatusNew.mprv := 0.U} //If the new privilege mode is less privileged than M-mode, MPRV in mstatus is cleared.
869    mstatus := mstatusNew.asUInt
870    priviledgeMode := dcsrNew.prv
871    retTarget := dpc(VAddrBits-1, 0)
872    debugModeNew := false.B
873    debugIntrEnable := true.B
874    debugMode := debugModeNew
875    XSDebug("Debug Mode: Dret executed, returning to %x.", retTarget)
876  }
877
878  when (valid && isMret && !illegalMret) {
879    val mstatusOld = WireInit(mstatus.asTypeOf(new MstatusStruct))
880    val mstatusNew = WireInit(mstatus.asTypeOf(new MstatusStruct))
881    mstatusNew.ie.m := mstatusOld.pie.m
882    priviledgeMode := mstatusOld.mpp
883    mstatusNew.pie.m := true.B
884    mstatusNew.mpp := ModeU
885    when (mstatusOld.mpp =/= ModeM) { mstatusNew.mprv := 0.U }
886    mstatus := mstatusNew.asUInt
887    // lr := false.B
888    retTarget := mepc(VAddrBits-1, 0)
889  }
890
891  when (valid && isSret && !illegalSret && !illegalSModeSret) {
892    val mstatusOld = WireInit(mstatus.asTypeOf(new MstatusStruct))
893    val mstatusNew = WireInit(mstatus.asTypeOf(new MstatusStruct))
894    mstatusNew.ie.s := mstatusOld.pie.s
895    priviledgeMode := Cat(0.U(1.W), mstatusOld.spp)
896    mstatusNew.pie.s := true.B
897    mstatusNew.spp := ModeU
898    mstatus := mstatusNew.asUInt
899    when (mstatusOld.spp =/= ModeM) { mstatusNew.mprv := 0.U }
900    // lr := false.B
901    retTarget := sepc(VAddrBits-1, 0)
902  }
903
904  when (valid && isUret) {
905    val mstatusOld = WireInit(mstatus.asTypeOf(new MstatusStruct))
906    val mstatusNew = WireInit(mstatus.asTypeOf(new MstatusStruct))
907    // mstatusNew.mpp.m := ModeU //TODO: add mode U
908    mstatusNew.ie.u := mstatusOld.pie.u
909    priviledgeMode := ModeU
910    mstatusNew.pie.u := true.B
911    mstatus := mstatusNew.asUInt
912    retTarget := uepc(VAddrBits-1, 0)
913  }
914
915  io.in.ready := true.B
916  io.out.valid := valid
917
918  val ebreakCauseException = (priviledgeMode === ModeM && dcsrData.ebreakm) || (priviledgeMode === ModeS && dcsrData.ebreaks) || (priviledgeMode === ModeU && dcsrData.ebreaku)
919
920  val csrExceptionVec = WireInit(cfIn.exceptionVec)
921  csrExceptionVec(breakPoint) := io.in.valid && isEbreak && (ebreakCauseException || debugMode)
922  csrExceptionVec(ecallM) := priviledgeMode === ModeM && io.in.valid && isEcall
923  csrExceptionVec(ecallS) := priviledgeMode === ModeS && io.in.valid && isEcall
924  csrExceptionVec(ecallU) := priviledgeMode === ModeU && io.in.valid && isEcall
925  // Trigger an illegal instr exception when:
926  // * unimplemented csr is being read/written
927  // * csr access is illegal
928  csrExceptionVec(illegalInstr) := isIllegalAddr || isIllegalAccess || isIllegalPrivOp
929  cfOut.exceptionVec := csrExceptionVec
930
931  XSDebug(io.in.valid && isEbreak, s"Debug Mode: an Ebreak is executed, ebreak cause exception ? ${ebreakCauseException}\n")
932
933  /**
934    * Exception and Intr
935    */
936  val ideleg =  (mideleg & mip.asUInt)
937  def priviledgedEnableDetect(x: Bool): Bool = Mux(x, ((priviledgeMode === ModeS) && mstatusStruct.ie.s) || (priviledgeMode < ModeS),
938    ((priviledgeMode === ModeM) && mstatusStruct.ie.m) || (priviledgeMode < ModeM))
939
940  val debugIntr = csrio.externalInterrupt.debug & debugIntrEnable
941  XSDebug(debugIntr, "Debug Mode: debug interrupt is asserted and valid!")
942  // send interrupt information to ROB
943  val intrVecEnable = Wire(Vec(12, Bool()))
944  val disableInterrupt = debugMode || (dcsrData.step && !dcsrData.stepie)
945  intrVecEnable.zip(ideleg.asBools).map{case(x,y) => x := priviledgedEnableDetect(y) && !disableInterrupt}
946  val intrVec = Cat(debugIntr && !debugMode, (mie(11,0) & mip.asUInt & intrVecEnable.asUInt))
947  val intrBitSet = intrVec.orR
948  csrio.interrupt := intrBitSet
949  // Page 45 in RISC-V Privileged Specification
950  // The WFI instruction can also be executed when interrupts are disabled. The operation of WFI
951  // must be unaffected by the global interrupt bits in mstatus (MIE and SIE) and the delegation
952  // register mideleg, but should honor the individual interrupt enables (e.g, MTIE).
953  csrio.wfi_event := debugIntr || (mie(11, 0) & mip.asUInt).orR
954  mipWire.t.m := csrio.externalInterrupt.mtip
955  mipWire.s.m := csrio.externalInterrupt.msip
956  mipWire.e.m := csrio.externalInterrupt.meip
957  mipWire.e.s := csrio.externalInterrupt.seip
958
959  // interrupts
960  val intrNO = IntPriority.foldRight(0.U)((i: Int, sum: UInt) => Mux(intrVec(i), i.U, sum))
961  val raiseIntr = csrio.exception.valid && csrio.exception.bits.isInterrupt
962  val ivmEnable = tlbBundle.priv.imode < ModeM && satp.asTypeOf(new SatpStruct).mode === 8.U
963  val iexceptionPC = Mux(ivmEnable, SignExt(csrio.exception.bits.uop.cf.pc, XLEN), csrio.exception.bits.uop.cf.pc)
964  val dvmEnable = tlbBundle.priv.dmode < ModeM && satp.asTypeOf(new SatpStruct).mode === 8.U
965  val dexceptionPC = Mux(dvmEnable, SignExt(csrio.exception.bits.uop.cf.pc, XLEN), csrio.exception.bits.uop.cf.pc)
966  XSDebug(raiseIntr, "interrupt: pc=0x%x, %d\n", dexceptionPC, intrNO)
967  val raiseDebugIntr = intrNO === IRQ_DEBUG.U && raiseIntr
968
969  // exceptions
970  val raiseException = csrio.exception.valid && !csrio.exception.bits.isInterrupt
971  val hasInstrPageFault = csrio.exception.bits.uop.cf.exceptionVec(instrPageFault) && raiseException
972  val hasLoadPageFault = csrio.exception.bits.uop.cf.exceptionVec(loadPageFault) && raiseException
973  val hasStorePageFault = csrio.exception.bits.uop.cf.exceptionVec(storePageFault) && raiseException
974  val hasStoreAddrMisaligned = csrio.exception.bits.uop.cf.exceptionVec(storeAddrMisaligned) && raiseException
975  val hasLoadAddrMisaligned = csrio.exception.bits.uop.cf.exceptionVec(loadAddrMisaligned) && raiseException
976  val hasInstrAccessFault = csrio.exception.bits.uop.cf.exceptionVec(instrAccessFault) && raiseException
977  val hasLoadAccessFault = csrio.exception.bits.uop.cf.exceptionVec(loadAccessFault) && raiseException
978  val hasStoreAccessFault = csrio.exception.bits.uop.cf.exceptionVec(storeAccessFault) && raiseException
979  val hasbreakPoint = csrio.exception.bits.uop.cf.exceptionVec(breakPoint) && raiseException
980  val hasSingleStep = csrio.exception.bits.uop.ctrl.singleStep && raiseException
981  val hasTriggerHit = (csrio.exception.bits.uop.cf.trigger.hit) && raiseException
982
983  XSDebug(hasSingleStep, "Debug Mode: single step exception\n")
984  XSDebug(hasTriggerHit, p"Debug Mode: trigger hit, is frontend? ${Binary(csrio.exception.bits.uop.cf.trigger.frontendHit.asUInt)} " +
985    p"backend hit vec ${Binary(csrio.exception.bits.uop.cf.trigger.backendHit.asUInt)}\n")
986
987  val raiseExceptionVec = csrio.exception.bits.uop.cf.exceptionVec
988  val regularExceptionNO = ExceptionNO.priorities.foldRight(0.U)((i: Int, sum: UInt) => Mux(raiseExceptionVec(i), i.U, sum))
989  val exceptionNO = Mux(hasSingleStep || hasTriggerHit, 3.U, regularExceptionNO)
990  val causeNO = (raiseIntr << (XLEN-1)).asUInt | Mux(raiseIntr, intrNO, exceptionNO)
991
992  val raiseExceptionIntr = csrio.exception.valid
993
994  val raiseDebugExceptionIntr = !debugMode && (hasbreakPoint || raiseDebugIntr || hasSingleStep || hasTriggerHit && triggerAction) // TODO
995  val ebreakEnterParkLoop = debugMode && raiseExceptionIntr
996
997  XSDebug(raiseExceptionIntr, "int/exc: pc %x int (%d):%x exc: (%d):%x\n",
998    dexceptionPC, intrNO, intrVec, exceptionNO, raiseExceptionVec.asUInt
999  )
1000  XSDebug(raiseExceptionIntr,
1001    "pc %x mstatus %x mideleg %x medeleg %x mode %x\n",
1002    dexceptionPC,
1003    mstatus,
1004    mideleg,
1005    medeleg,
1006    priviledgeMode
1007  )
1008
1009  // mtval write logic
1010  // Due to timing reasons of memExceptionVAddr, we delay the write of mtval and stval
1011  val memExceptionAddr = SignExt(csrio.memExceptionVAddr, XLEN)
1012  val updateTval = VecInit(Seq(
1013    hasInstrPageFault,
1014    hasLoadPageFault,
1015    hasStorePageFault,
1016    hasInstrAccessFault,
1017    hasLoadAccessFault,
1018    hasStoreAccessFault,
1019    hasLoadAddrMisaligned,
1020    hasStoreAddrMisaligned
1021  )).asUInt.orR
1022  when (RegNext(RegNext(updateTval))) {
1023      val tval = Mux(
1024        RegNext(RegNext(hasInstrPageFault || hasInstrAccessFault)),
1025        RegNext(RegNext(Mux(
1026          csrio.exception.bits.uop.cf.crossPageIPFFix,
1027          SignExt(csrio.exception.bits.uop.cf.pc + 2.U, XLEN),
1028          iexceptionPC
1029        ))),
1030        memExceptionAddr
1031    )
1032    when (RegNext(priviledgeMode === ModeM)) {
1033      mtval := tval
1034    }.otherwise {
1035      stval := tval
1036    }
1037  }
1038
1039  val debugTrapTarget = Mux(!isEbreak && debugMode, 0x38020808.U, 0x38020800.U) // 0x808 is when an exception occurs in debug mode prog buf exec
1040  val deleg = Mux(raiseIntr, mideleg , medeleg)
1041  // val delegS = ((deleg & (1 << (causeNO & 0xf))) != 0) && (priviledgeMode < ModeM);
1042  val delegS = deleg(causeNO(3,0)) && (priviledgeMode < ModeM)
1043  val clearTval = !updateTval || raiseIntr
1044  val isXRet = io.in.valid && func === CSROpType.jmp && !isEcall && !isEbreak
1045
1046  // ctrl block will use theses later for flush
1047  val isXRetFlag = RegInit(false.B)
1048  when (DelayN(io.redirectIn.valid, 5)) {
1049    isXRetFlag := false.B
1050  }.elsewhen (isXRet) {
1051    isXRetFlag := true.B
1052  }
1053  csrio.isXRet := isXRetFlag
1054  val retTargetReg = RegEnable(retTarget, isXRet)
1055
1056  val tvec = Mux(delegS, stvec, mtvec)
1057  val tvecBase = tvec(VAddrBits - 1, 2)
1058  // XRet sends redirect instead of Flush and isXRetFlag is true.B before redirect.valid.
1059  // ROB sends exception at T0 while CSR receives at T2.
1060  // We add a RegNext here and trapTarget is valid at T3.
1061  csrio.trapTarget := RegEnable(Mux(isXRetFlag,
1062    retTargetReg,
1063    Mux(raiseDebugExceptionIntr || ebreakEnterParkLoop, debugTrapTarget,
1064      // When MODE=Vectored, all synchronous exceptions into M/S mode
1065      // cause the pc to be set to the address in the BASE field, whereas
1066      // interrupts cause the pc to be set to the address in the BASE field
1067      // plus four times the interrupt cause number.
1068      Cat(tvecBase + Mux(tvec(0) && raiseIntr, causeNO(3, 0), 0.U), 0.U(2.W))
1069  )), isXRetFlag || csrio.exception.valid)
1070
1071  when (raiseExceptionIntr) {
1072    val mstatusOld = WireInit(mstatus.asTypeOf(new MstatusStruct))
1073    val mstatusNew = WireInit(mstatus.asTypeOf(new MstatusStruct))
1074    val dcsrNew = WireInit(dcsr.asTypeOf(new DcsrStruct))
1075    val debugModeNew = WireInit(debugMode)
1076
1077    when (raiseDebugExceptionIntr) {
1078      when (raiseDebugIntr) {
1079        debugModeNew := true.B
1080        mstatusNew.mprv := false.B
1081        dpc := iexceptionPC
1082        dcsrNew.cause := 3.U
1083        dcsrNew.prv := priviledgeMode
1084        priviledgeMode := ModeM
1085        XSDebug(raiseDebugIntr, "Debug Mode: Trap to %x at pc %x\n", debugTrapTarget, dpc)
1086      }.elsewhen ((hasbreakPoint || hasSingleStep) && !debugMode) {
1087        // ebreak or ss in running hart
1088        debugModeNew := true.B
1089        dpc := iexceptionPC
1090        dcsrNew.cause := Mux(hasTriggerHit, 2.U, Mux(hasbreakPoint, 1.U, 4.U))
1091        dcsrNew.prv := priviledgeMode // TODO
1092        priviledgeMode := ModeM
1093        mstatusNew.mprv := false.B
1094      }
1095      dcsr := dcsrNew.asUInt
1096      debugIntrEnable := false.B
1097    }.elsewhen (debugMode) {
1098      //do nothing
1099    }.elsewhen (delegS) {
1100      scause := causeNO
1101      sepc := Mux(hasInstrPageFault || hasInstrAccessFault, iexceptionPC, dexceptionPC)
1102      mstatusNew.spp := priviledgeMode
1103      mstatusNew.pie.s := mstatusOld.ie.s
1104      mstatusNew.ie.s := false.B
1105      priviledgeMode := ModeS
1106      when (clearTval) { stval := 0.U }
1107    }.otherwise {
1108      mcause := causeNO
1109      mepc := Mux(hasInstrPageFault || hasInstrAccessFault, iexceptionPC, dexceptionPC)
1110      mstatusNew.mpp := priviledgeMode
1111      mstatusNew.pie.m := mstatusOld.ie.m
1112      mstatusNew.ie.m := false.B
1113      priviledgeMode := ModeM
1114      when (clearTval) { mtval := 0.U }
1115    }
1116    mstatus := mstatusNew.asUInt
1117    debugMode := debugModeNew
1118  }
1119
1120  XSDebug(raiseExceptionIntr && delegS, "sepc is written!!! pc:%x\n", cfIn.pc)
1121
1122  // Distributed CSR update req
1123  //
1124  // For now we use it to implement customized cache op
1125  // It can be delayed if necessary
1126
1127  val delayedUpdate0 = DelayN(csrio.distributedUpdate(0), 2)
1128  val delayedUpdate1 = DelayN(csrio.distributedUpdate(1), 2)
1129  val distributedUpdateValid = delayedUpdate0.w.valid || delayedUpdate1.w.valid
1130  val distributedUpdateAddr = Mux(delayedUpdate0.w.valid,
1131    delayedUpdate0.w.bits.addr,
1132    delayedUpdate1.w.bits.addr
1133  )
1134  val distributedUpdateData = Mux(delayedUpdate0.w.valid,
1135    delayedUpdate0.w.bits.data,
1136    delayedUpdate1.w.bits.data
1137  )
1138
1139  assert(!(delayedUpdate0.w.valid && delayedUpdate1.w.valid))
1140
1141  when(distributedUpdateValid){
1142    // cacheopRegs can be distributed updated
1143    CacheInstrucion.CacheInsRegisterList.map{case (name, attribute) => {
1144      when((Scachebase + attribute("offset").toInt).U === distributedUpdateAddr){
1145        cacheopRegs(name) := distributedUpdateData
1146      }
1147    }}
1148  }
1149
1150  // Cache error debug support
1151  if(HasCustomCSRCacheOp){
1152    val cache_error_decoder = Module(new CSRCacheErrorDecoder)
1153    cache_error_decoder.io.encoded_cache_error := cacheopRegs("CACHE_ERROR")
1154  }
1155
1156  // Implicit add reset values for mepc[0] and sepc[0]
1157  // TODO: rewrite mepc and sepc using a struct-like style with the LSB always being 0
1158  when (reset.asBool) {
1159    mepc := Cat(mepc(XLEN - 1, 1), 0.U(1.W))
1160    sepc := Cat(sepc(XLEN - 1, 1), 0.U(1.W))
1161  }
1162
1163  def readWithScala(addr: Int): UInt = mapping(addr)._1
1164
1165  val difftestIntrNO = Mux(raiseIntr, causeNO, 0.U)
1166
1167  // Always instantiate basic difftest modules.
1168  if (env.AlwaysBasicDiff || env.EnableDifftest) {
1169    val difftest = Module(new DifftestArchEvent)
1170    difftest.io.clock := clock
1171    difftest.io.coreid := csrio.hartId
1172    difftest.io.intrNO := RegNext(RegNext(RegNext(difftestIntrNO)))
1173    difftest.io.cause  := RegNext(RegNext(RegNext(Mux(csrio.exception.valid, causeNO, 0.U))))
1174    difftest.io.exceptionPC := RegNext(RegNext(RegNext(dexceptionPC)))
1175    if (env.EnableDifftest) {
1176      difftest.io.exceptionInst := RegNext(RegNext(RegNext(csrio.exception.bits.uop.cf.instr)))
1177    }
1178  }
1179
1180  // Always instantiate basic difftest modules.
1181  if (env.AlwaysBasicDiff || env.EnableDifftest) {
1182    val difftest = Module(new DifftestCSRState)
1183    difftest.io.clock := clock
1184    difftest.io.coreid := csrio.hartId
1185    difftest.io.priviledgeMode := priviledgeMode
1186    difftest.io.mstatus := mstatus
1187    difftest.io.sstatus := mstatus & sstatusRmask
1188    difftest.io.mepc := mepc
1189    difftest.io.sepc := sepc
1190    difftest.io.mtval:= mtval
1191    difftest.io.stval:= stval
1192    difftest.io.mtvec := mtvec
1193    difftest.io.stvec := stvec
1194    difftest.io.mcause := mcause
1195    difftest.io.scause := scause
1196    difftest.io.satp := satp
1197    difftest.io.mip := mipReg
1198    difftest.io.mie := mie
1199    difftest.io.mscratch := mscratch
1200    difftest.io.sscratch := sscratch
1201    difftest.io.mideleg := mideleg
1202    difftest.io.medeleg := medeleg
1203  }
1204
1205  if(env.AlwaysBasicDiff || env.EnableDifftest) {
1206    val difftest = Module(new DifftestDebugMode)
1207    difftest.io.clock := clock
1208    difftest.io.coreid := csrio.hartId
1209    difftest.io.debugMode := debugMode
1210    difftest.io.dcsr := dcsr
1211    difftest.io.dpc := dpc
1212    difftest.io.dscratch0 := dscratch
1213    difftest.io.dscratch1 := dscratch1
1214  }
1215}
1216
1217class PFEvent(implicit p: Parameters) extends XSModule with HasCSRConst  {
1218  val io = IO(new Bundle {
1219    val distribute_csr = Flipped(new DistributedCSRIO())
1220    val hpmevent = Output(Vec(29, UInt(XLEN.W)))
1221  })
1222
1223  val w = io.distribute_csr.w
1224
1225  val perfEvents = List.fill(8)(RegInit("h0000000000".U(XLEN.W))) ++
1226                   List.fill(8)(RegInit("h4010040100".U(XLEN.W))) ++
1227                   List.fill(8)(RegInit("h8020080200".U(XLEN.W))) ++
1228                   List.fill(5)(RegInit("hc0300c0300".U(XLEN.W)))
1229
1230  val perfEventMapping = (0 until 29).map(i => {Map(
1231    MaskedRegMap(addr = Mhpmevent3 +i,
1232                 reg  = perfEvents(i),
1233                 wmask = "hf87fff3fcff3fcff".U(XLEN.W))
1234  )}).fold(Map())((a,b) => a ++ b)
1235
1236  val rdata = Wire(UInt(XLEN.W))
1237  MaskedRegMap.generate(perfEventMapping, w.bits.addr, rdata, w.valid, w.bits.data)
1238  for(i <- 0 until 29){
1239    io.hpmevent(i) := perfEvents(i)
1240  }
1241}
1242