xref: /XiangShan/src/main/scala/xiangshan/cache/mmu/L2TLB.scala (revision d61cd5eecdc204c74ec210166665a10f4eb680f1)
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.cache.mmu
18
19import org.chipsalliance.cde.config.Parameters
20import chisel3._
21import chisel3.experimental.ExtModule
22import chisel3.util._
23import xiangshan._
24import xiangshan.cache.{HasDCacheParameters, MemoryOpConstants}
25import utils._
26import utility._
27import freechips.rocketchip.diplomacy.{IdRange, LazyModule, LazyModuleImp}
28import freechips.rocketchip.tilelink._
29import xiangshan.backend.fu.{PMP, PMPChecker, PMPReqBundle, PMPRespBundle}
30import xiangshan.backend.fu.util.HasCSRConst
31import difftest._
32
33class L2TLB()(implicit p: Parameters) extends LazyModule with HasPtwConst {
34  override def shouldBeInlined: Boolean = false
35
36  val node = TLClientNode(Seq(TLMasterPortParameters.v1(
37    clients = Seq(TLMasterParameters.v1(
38      "ptw",
39      sourceId = IdRange(0, MemReqWidth)
40    )),
41    requestFields = Seq(ReqSourceField())
42  )))
43
44  lazy val module = new L2TLBImp(this)
45}
46
47class L2TLBImp(outer: L2TLB)(implicit p: Parameters) extends PtwModule(outer) with HasCSRConst with HasPerfEvents {
48
49  val (mem, edge) = outer.node.out.head
50
51  val io = IO(new L2TLBIO)
52  val difftestIO = IO(new Bundle() {
53    val ptwResp = Output(Bool())
54    val ptwAddr = Output(UInt(64.W))
55    val ptwData = Output(Vec(4, UInt(64.W)))
56  })
57
58  /* Ptw processes multiple requests
59   * Divide Ptw procedure into two stages: cache access ; mem access if cache miss
60   *           miss queue itlb       dtlb
61   *               |       |         |
62   *               ------arbiter------
63   *                            |
64   *                    l1 - l2 - l3 - sp
65   *                            |
66   *          -------------------------------------------
67   *    miss  |  queue                                  | hit
68   *    [][][][][][]                                    |
69   *          |                                         |
70   *    state machine accessing mem                     |
71   *          |                                         |
72   *          ---------------arbiter---------------------
73   *                 |                    |
74   *                itlb                 dtlb
75   */
76
77  difftestIO <> DontCare
78
79  val sfence_tmp = DelayN(io.sfence, 1)
80  val csr_tmp    = DelayN(io.csr.tlb, 1)
81  val sfence_dup = Seq.fill(9)(RegNext(sfence_tmp))
82  val csr_dup = Seq.fill(8)(RegNext(csr_tmp))
83  val satp   = csr_dup(0).satp
84  val vsatp  = csr_dup(0).vsatp
85  val hgatp  = csr_dup(0).hgatp
86  val priv   = csr_dup(0).priv
87  val flush  = sfence_dup(0).valid || satp.changed || vsatp.changed || hgatp.changed
88
89  val pmp = Module(new PMP())
90  val pmp_check = VecInit(Seq.fill(2)(Module(new PMPChecker(lgMaxSize = 3, sameCycle = true)).io))
91  pmp.io.distribute_csr := io.csr.distribute_csr
92  pmp_check.foreach(_.check_env.apply(ModeS, pmp.io.pmp, pmp.io.pma))
93
94  val missQueue = Module(new L2TlbMissQueue)
95  val cache = Module(new PtwCache)
96  val ptw = Module(new PTW)
97  val hptw = Module(new HPTW)
98  val llptw = Module(new LLPTW)
99  val blockmq = Module(new BlockHelper(3))
100  val arb1 = Module(new Arbiter(new PtwReq, PtwWidth))
101  val arb2 = Module(new Arbiter(new Bundle {
102    val vpn = UInt(vpnLen.W)
103    val s2xlate = UInt(2.W)
104    val source = UInt(bSourceWidth.W)
105  }, if (l2tlbParams.enablePrefetch) 4 else 3 + (if(HasHExtension) 1 else 0)))
106  val hptw_req_arb = Module(new Arbiter(new Bundle {
107    val id = UInt(log2Up(l2tlbParams.llptwsize).W)
108    val gvpn = UInt(vpnLen.W)
109  }, 2))
110  val hptw_resp_arb = Module(new Arbiter(new Bundle {
111    val resp = new HptwResp()
112    val id = UInt(log2Up(l2tlbParams.llptwsize).W)
113  }, 2))
114  val outArb = (0 until PtwWidth).map(i => Module(new Arbiter(new Bundle {
115    val s2xlate = UInt(2.W)
116    val s1Resp = new PtwSectorResp ()
117    val s2Resp = new HptwResp()
118  }, 1)).io)
119  val mergeArb = (0 until PtwWidth).map(i => Module(new Arbiter(new Bundle {
120    val s2xlate = UInt(2.W)
121    val s1Resp = new PtwMergeResp()
122    val s2Resp = new HptwResp()
123  }, 3)).io)
124  val outArbCachePort = 0
125  val outArbFsmPort = 1
126  val outArbMqPort = 2
127
128  // hptw arb input port
129  val InHptwArbPTWPort = 0
130  val InHptwArbLLPTWPort = 1
131  hptw_req_arb.io.in(InHptwArbPTWPort).valid := ptw.io.hptw.req.valid
132  hptw_req_arb.io.in(InHptwArbPTWPort).bits.gvpn := ptw.io.hptw.req.bits.gvpn
133  hptw_req_arb.io.in(InHptwArbPTWPort).bits.id := ptw.io.hptw.req.bits.id
134  ptw.io.hptw.req.ready := hptw_req_arb.io.in(InHptwArbPTWPort).ready
135
136  hptw_req_arb.io.in(InHptwArbLLPTWPort).valid := llptw.io.hptw.req.valid
137  hptw_req_arb.io.in(InHptwArbLLPTWPort).bits.gvpn := llptw.io.hptw.req.bits.gvpn
138  hptw_req_arb.io.in(InHptwArbLLPTWPort).bits.id := llptw.io.hptw.req.bits.id
139  llptw.io.hptw.req.ready := hptw_req_arb.io.in(InHptwArbLLPTWPort).ready
140
141  val hptw_id = RegInit(0.U(log2Up(l2tlbParams.llptwsize).W))
142  when(hptw_req_arb.io.out.valid) {
143    hptw_id := hptw_req_arb.io.out.bits.id
144  }
145  // arb2 input port
146  val InArbPTWPort = 0
147  val InArbMissQueuePort = 1
148  val InArbTlbPort = 2
149  val InArbPrefetchPort = 3
150  val InArbHPTWPort = 4
151  // NOTE: when cache out but miss and ptw doesnt accept,
152  arb1.io.in <> VecInit(io.tlb.map(_.req(0)))
153  arb1.io.out.ready := arb2.io.in(InArbTlbPort).ready
154
155  arb2.io.in(InArbPTWPort).valid := ptw.io.llptw.valid
156  arb2.io.in(InArbPTWPort).bits.vpn := ptw.io.llptw.bits.req_info.vpn
157  arb2.io.in(InArbPTWPort).bits.s2xlate := ptw.io.llptw.bits.req_info.s2xlate
158  arb2.io.in(InArbPTWPort).bits.source := ptw.io.llptw.bits.req_info.source
159  ptw.io.llptw.ready := arb2.io.in(InArbPTWPort).ready
160  block_decoupled(missQueue.io.out, arb2.io.in(InArbMissQueuePort), !ptw.io.req.ready)
161
162  arb2.io.in(InArbTlbPort).valid := arb1.io.out.valid
163  arb2.io.in(InArbTlbPort).bits.vpn := arb1.io.out.bits.vpn
164  arb2.io.in(InArbTlbPort).bits.s2xlate := arb1.io.out.bits.s2xlate
165  arb2.io.in(InArbTlbPort).bits.source := arb1.io.chosen
166
167  arb2.io.in(InArbHPTWPort).valid := hptw_req_arb.io.out.valid
168  arb2.io.in(InArbHPTWPort).bits.vpn := hptw_req_arb.io.out.bits.gvpn
169  arb2.io.in(InArbHPTWPort).bits.s2xlate := onlyStage2
170  arb2.io.in(InArbHPTWPort).bits.source := DontCare
171  if (l2tlbParams.enablePrefetch) {
172    val prefetch = Module(new L2TlbPrefetch())
173    val recv = cache.io.resp
174    // NOTE: 1. prefetch doesn't gen prefetch 2. req from mq doesn't gen prefetch
175    // NOTE: 1. miss req gen prefetch 2. hit but prefetched gen prefetch
176    prefetch.io.in.valid := recv.fire && !from_pre(recv.bits.req_info.source) && (!recv.bits.hit  ||
177      recv.bits.prefetch) && recv.bits.isFirst
178    prefetch.io.in.bits.vpn := recv.bits.req_info.vpn
179    prefetch.io.sfence := sfence_dup(0)
180    prefetch.io.csr := csr_dup(0)
181    arb2.io.in(InArbPrefetchPort) <> prefetch.io.out
182
183    val isWriteL2TlbPrefetchTable = WireInit(Constantin.createRecord("isWriteL2TlbPrefetchTable" + p(XSCoreParamsKey).HartId.toString))
184    val L2TlbPrefetchTable = ChiselDB.createTable("L2TlbPrefetch_hart" + p(XSCoreParamsKey).HartId.toString, new L2TlbPrefetchDB)
185    val L2TlbPrefetchDB = Wire(new L2TlbPrefetchDB)
186    L2TlbPrefetchDB.vpn := prefetch.io.out.bits.vpn
187    L2TlbPrefetchTable.log(L2TlbPrefetchDB, isWriteL2TlbPrefetchTable.orR && prefetch.io.out.fire, "L2TlbPrefetch", clock, reset)
188  }
189  arb2.io.out.ready := cache.io.req.ready
190
191
192  val mq_arb = Module(new Arbiter(new L2TlbInnerBundle, 2))
193  mq_arb.io.in(0).valid := cache.io.resp.valid && !cache.io.resp.bits.hit &&
194    (!cache.io.resp.bits.toFsm.l2Hit || cache.io.resp.bits.bypassed) &&
195    !from_pre(cache.io.resp.bits.req_info.source) &&
196    (cache.io.resp.bits.bypassed || cache.io.resp.bits.isFirst || !ptw.io.req.ready)
197  mq_arb.io.in(0).bits :=  cache.io.resp.bits.req_info
198  mq_arb.io.in(1) <> llptw.io.cache
199  missQueue.io.in <> mq_arb.io.out
200  missQueue.io.sfence  := sfence_dup(6)
201  missQueue.io.csr := csr_dup(5)
202
203  blockmq.io.start := missQueue.io.out.fire
204  blockmq.io.enable := ptw.io.req.fire
205
206  llptw.io.in.valid := cache.io.resp.valid &&
207    !cache.io.resp.bits.hit &&
208    cache.io.resp.bits.toFsm.l2Hit &&
209    !cache.io.resp.bits.bypassed &&
210    !cache.io.resp.bits.isHptw
211  llptw.io.in.bits.req_info := cache.io.resp.bits.req_info
212  llptw.io.in.bits.ppn := cache.io.resp.bits.toFsm.ppn
213  llptw.io.sfence := sfence_dup(1)
214  llptw.io.csr := csr_dup(1)
215
216  cache.io.req.valid := arb2.io.out.valid
217  cache.io.req.bits.req_info.vpn := arb2.io.out.bits.vpn
218  cache.io.req.bits.req_info.s2xlate := arb2.io.out.bits.s2xlate
219  cache.io.req.bits.req_info.source := arb2.io.out.bits.source
220  cache.io.req.bits.isFirst := arb2.io.chosen =/= InArbMissQueuePort.U
221  cache.io.req.bits.isHptw := arb2.io.chosen === InArbHPTWPort.U
222  cache.io.req.bits.hptwId := hptw_id
223  cache.io.req.bits.bypassed.map(_ := false.B)
224  cache.io.sfence := sfence_dup(2)
225  cache.io.csr := csr_dup(2)
226  cache.io.sfence_dup.zip(sfence_dup.drop(2).take(4)).map(s => s._1 := s._2)
227  cache.io.csr_dup.zip(csr_dup.drop(2).take(3)).map(c => c._1 := c._2)
228  cache.io.resp.ready := Mux(cache.io.resp.bits.hit,
229    outReady(cache.io.resp.bits.req_info.source, outArbCachePort),
230    Mux(cache.io.resp.bits.toFsm.l2Hit && !cache.io.resp.bits.bypassed, llptw.io.in.ready,
231    Mux(cache.io.resp.bits.bypassed || cache.io.resp.bits.isFirst, mq_arb.io.in(0).ready, mq_arb.io.in(0).ready || ptw.io.req.ready)))
232
233  // NOTE: missQueue req has higher priority
234  ptw.io.req.valid := cache.io.resp.valid && !cache.io.resp.bits.hit && !cache.io.resp.bits.toFsm.l2Hit &&
235    !cache.io.resp.bits.bypassed &&
236    !cache.io.resp.bits.isFirst &&
237    !cache.io.resp.bits.isHptw
238  ptw.io.req.bits.req_info := cache.io.resp.bits.req_info
239  ptw.io.req.bits.l1Hit := cache.io.resp.bits.toFsm.l1Hit
240  ptw.io.req.bits.ppn := cache.io.resp.bits.toFsm.ppn
241  ptw.io.sfence := sfence_dup(7)
242  ptw.io.csr := csr_dup(6)
243  ptw.io.resp.ready := outReady(ptw.io.resp.bits.source, outArbFsmPort)
244
245  hptw.io.req.valid := cache.io.resp.valid && !cache.io.resp.bits.hit && !cache.io.resp.bits.bypassed & cache.io.resp.bits.isHptw
246  hptw.io.req.bits.gvpn := cache.io.resp.bits.req_info.vpn
247  hptw.io.req.bits.id := cache.io.resp.bits.toHptw.id
248  hptw.io.req.bits.l1Hit := cache.io.resp.bits.toHptw.l1Hit
249  hptw.io.req.bits.l2Hit := cache.io.resp.bits.toHptw.l2Hit
250  hptw.io.sfence := sfence_dup(8)
251  hptw.io.csr := csr_dup(7)
252  // mem req
253  def blockBytes_align(addr: UInt) = {
254    Cat(addr(PAddrBits - 1, log2Up(l2tlbParams.blockBytes)), 0.U(log2Up(l2tlbParams.blockBytes).W))
255  }
256  def addr_low_from_vpn(vpn: UInt) = {
257    vpn(log2Ceil(l2tlbParams.blockBytes)-log2Ceil(XLEN/8)-1, 0)
258  }
259  def addr_low_from_paddr(paddr: UInt) = {
260    paddr(log2Up(l2tlbParams.blockBytes)-1, log2Up(XLEN/8))
261  }
262  def from_llptw(id: UInt) = {
263    id < l2tlbParams.llptwsize.U
264  }
265  def from_ptw(id: UInt) = {
266    id === l2tlbParams.llptwsize.U
267  }
268  def from_hptw(id: UInt) = {
269    id === l2tlbParams.llptwsize.U + 1.U
270  }
271  val waiting_resp = RegInit(VecInit(Seq.fill(MemReqWidth)(false.B)))
272  val flush_latch = RegInit(VecInit(Seq.fill(MemReqWidth)(false.B)))
273  for (i <- waiting_resp.indices) {
274    assert(!flush_latch(i) || waiting_resp(i)) // when sfence_latch wait for mem resp, waiting_resp should be true
275  }
276
277  val llptw_out = llptw.io.out
278  val llptw_mem = llptw.io.mem
279  llptw_mem.req_mask := waiting_resp.take(l2tlbParams.llptwsize)
280  ptw.io.mem.mask := waiting_resp.apply(l2tlbParams.llptwsize)
281  hptw.io.mem.mask := waiting_resp.apply(l2tlbParams.llptwsize + 1)
282
283  val mem_arb = Module(new Arbiter(new L2TlbMemReqBundle(), 3))
284  mem_arb.io.in(0) <> ptw.io.mem.req
285  mem_arb.io.in(1) <> llptw_mem.req
286  mem_arb.io.in(2) <> hptw.io.mem.req
287  mem_arb.io.out.ready := mem.a.ready && !flush
288
289  // assert, should not send mem access at same addr for twice.
290  val last_resp_vpn = RegEnable(cache.io.refill.bits.req_info_dup(0).vpn, cache.io.refill.valid)
291  val last_resp_level = RegEnable(cache.io.refill.bits.level_dup(0), cache.io.refill.valid)
292  val last_resp_v = RegInit(false.B)
293  val last_has_invalid = !Cat(cache.io.refill.bits.ptes.asTypeOf(Vec(blockBits/XLEN, UInt(XLEN.W))).map(a => a(0))).andR || cache.io.refill.bits.sel_pte_dup(0).asTypeOf(new PteBundle).isAf()
294  when (cache.io.refill.valid) { last_resp_v := !last_has_invalid}
295  when (flush) { last_resp_v := false.B }
296  XSError(last_resp_v && cache.io.refill.valid &&
297    (cache.io.refill.bits.req_info_dup(0).vpn === last_resp_vpn) &&
298    (cache.io.refill.bits.level_dup(0) === last_resp_level),
299    "l2tlb should not access mem at same addr for twice")
300  // ATTENTION: this may wrongly assert when: a ptes is l2, last part is valid,
301  // but the current part is invalid, so one more mem access happened
302  // If this happened, remove the assert.
303
304  val req_addr_low = Reg(Vec(MemReqWidth, UInt((log2Up(l2tlbParams.blockBytes)-log2Up(XLEN/8)).W)))
305
306  when (llptw.io.in.fire) {
307    // when enq miss queue, set the req_addr_low to receive the mem resp data part
308    req_addr_low(llptw_mem.enq_ptr) := addr_low_from_vpn(llptw.io.in.bits.req_info.vpn)
309  }
310  when (mem_arb.io.out.fire) {
311    req_addr_low(mem_arb.io.out.bits.id) := addr_low_from_paddr(mem_arb.io.out.bits.addr)
312    waiting_resp(mem_arb.io.out.bits.id) := true.B
313  }
314  // mem read
315  val memRead =  edge.Get(
316    fromSource = mem_arb.io.out.bits.id,
317    // toAddress  = memAddr(log2Up(CacheLineSize / 2 / 8) - 1, 0),
318    toAddress  = blockBytes_align(mem_arb.io.out.bits.addr),
319    lgSize     = log2Up(l2tlbParams.blockBytes).U
320  )._2
321  mem.a.bits := memRead
322  mem.a.valid := mem_arb.io.out.valid && !flush
323  mem.a.bits.user.lift(ReqSourceKey).foreach(_ := MemReqSource.PTW.id.U)
324  mem.d.ready := true.B
325  // mem -> data buffer
326  val refill_data = Reg(Vec(blockBits / l1BusDataWidth, UInt(l1BusDataWidth.W)))
327  val refill_helper = edge.firstlastHelper(mem.d.bits, mem.d.fire)
328  val mem_resp_done = refill_helper._3
329  val mem_resp_from_llptw = from_llptw(mem.d.bits.source)
330  val mem_resp_from_ptw = from_ptw(mem.d.bits.source)
331  val mem_resp_from_hptw = from_hptw(mem.d.bits.source)
332  when (mem.d.valid) {
333    assert(mem.d.bits.source < MemReqWidth.U)
334    refill_data(refill_helper._4) := mem.d.bits.data
335  }
336  // refill_data_tmp is the wire fork of refill_data, but one cycle earlier
337  val refill_data_tmp = WireInit(refill_data)
338  refill_data_tmp(refill_helper._4) := mem.d.bits.data
339
340  // save only one pte for each id
341  // (miss queue may can't resp to tlb with low latency, it should have highest priority, but diffcult to design cache)
342  val resp_pte = VecInit((0 until MemReqWidth).map(i =>
343    if (i == l2tlbParams.llptwsize + 1) {RegEnable(get_part(refill_data_tmp, req_addr_low(i)), mem_resp_done && mem_resp_from_hptw) }
344    else if (i == l2tlbParams.llptwsize) {RegEnable(get_part(refill_data_tmp, req_addr_low(i)), mem_resp_done && mem_resp_from_ptw) }
345    else { DataHoldBypass(get_part(refill_data, req_addr_low(i)), llptw_mem.buffer_it(i)) }
346    // llptw could not use refill_data_tmp, because enq bypass's result works at next cycle
347  ))
348
349  // save eight ptes for each id when sector tlb
350  // (miss queue may can't resp to tlb with low latency, it should have highest priority, but diffcult to design cache)
351  val resp_pte_sector = VecInit((0 until MemReqWidth).map(i =>
352    if (i == l2tlbParams.llptwsize + 1) {RegEnable(refill_data_tmp, mem_resp_done && mem_resp_from_hptw) }
353    else if (i == l2tlbParams.llptwsize) {RegEnable(refill_data_tmp, mem_resp_done && mem_resp_from_ptw) }
354    else { DataHoldBypass(refill_data, llptw_mem.buffer_it(i)) }
355    // llptw could not use refill_data_tmp, because enq bypass's result works at next cycle
356  ))
357
358  // mem -> llptw
359  llptw_mem.resp.valid := mem_resp_done && mem_resp_from_llptw
360  llptw_mem.resp.bits.id := DataHoldBypass(mem.d.bits.source, mem.d.valid)
361  // mem -> ptw
362  ptw.io.mem.req.ready := mem.a.ready
363  ptw.io.mem.resp.valid := mem_resp_done && mem_resp_from_ptw
364  ptw.io.mem.resp.bits := resp_pte.apply(l2tlbParams.llptwsize)
365  // mem -> hptw
366  hptw.io.mem.req.ready := mem.a.ready
367  hptw.io.mem.resp.valid := mem_resp_done && mem_resp_from_hptw
368  hptw.io.mem.resp.bits := resp_pte.apply(l2tlbParams.llptwsize + 1)
369  // mem -> cache
370  val refill_from_llptw = mem_resp_from_llptw
371  val refill_from_ptw = mem_resp_from_ptw
372  val refill_from_hptw = mem_resp_from_hptw
373  val refill_level = Mux(refill_from_llptw, 2.U, Mux(refill_from_ptw, RegEnable(ptw.io.refill.level, init = 0.U, ptw.io.mem.req.fire()), RegEnable(hptw.io.refill.level, init = 0.U, hptw.io.mem.req.fire())))
374  val refill_valid = mem_resp_done && !flush && !flush_latch(mem.d.bits.source)
375
376  cache.io.refill.valid := RegNext(refill_valid, false.B)
377  cache.io.refill.bits.ptes := refill_data.asUInt
378  cache.io.refill.bits.req_info_dup.map(_ := RegEnable(Mux(refill_from_llptw, llptw_mem.refill, Mux(refill_from_ptw, ptw.io.refill.req_info, hptw.io.refill.req_info)), refill_valid))
379  cache.io.refill.bits.level_dup.map(_ := RegEnable(refill_level, refill_valid))
380  cache.io.refill.bits.levelOH(refill_level, refill_valid)
381  cache.io.refill.bits.sel_pte_dup.map(_ := RegNext(sel_data(refill_data_tmp.asUInt, req_addr_low(mem.d.bits.source))))
382
383  if (env.EnableDifftest) {
384    val difftest_ptw_addr = RegInit(VecInit(Seq.fill(MemReqWidth)(0.U(PAddrBits.W))))
385    when (mem.a.valid) {
386      difftest_ptw_addr(mem.a.bits.source) := mem.a.bits.address
387    }
388
389    val difftest = DifftestModule(new DiffRefillEvent, dontCare = true)
390    difftest.coreid := io.hartId
391    difftest.index := 2.U
392    difftest.valid := cache.io.refill.valid
393    difftest.addr := difftest_ptw_addr(RegNext(mem.d.bits.source))
394    difftest.data := refill_data.asTypeOf(difftest.data)
395    difftest.idtfr := DontCare
396  }
397
398  if (env.EnableDifftest) {
399    for (i <- 0 until PtwWidth) {
400      val difftest = DifftestModule(new DiffL2TLBEvent)
401      difftest.coreid := io.hartId
402      difftest.valid := io.tlb(i).resp.fire && !io.tlb(i).resp.bits.s1.af && !io.tlb(i).resp.bits.s2.gaf
403      difftest.index := i.U
404      difftest.satp := io.csr.tlb.satp.ppn
405      difftest.vpn := Cat(io.tlb(i).resp.bits.entry.tag, 0.U(sectortlbwidth.W))
406      for (j <- 0 until tlbcontiguous) {
407        difftest.ppn(j) := Cat(io.tlb(i).resp.bits.entry.ppn, io.tlb(i).resp.bits.ppn_low(j))
408        difftest.valididx(j) := io.tlb(i).resp.bits.valididx(j)
409        difftest.io.pteidx(j) := io.tlb(i).resp.bits.s1.pteidx(j)
410      }
411      difftest.perm := io.tlb(i).resp.bits.entry.perm.getOrElse(0.U.asTypeOf(new PtePermBundle)).asUInt
412      difftest.level := io.tlb(i).resp.bits.entry.level.getOrElse(0.U.asUInt)
413      difftest.pf := io.tlb(i).resp.bits.pf
414    }
415  }
416
417  // pmp
418  pmp_check(0).req <> ptw.io.pmp.req
419  ptw.io.pmp.resp <> pmp_check(0).resp
420  pmp_check(1).req <> llptw.io.pmp.req
421  llptw.io.pmp.resp <> pmp_check(1).resp
422
423  llptw_out.ready := outReady(llptw_out.bits.req_info.source, outArbMqPort)
424
425  // hptw and page cache -> ptw and llptw
426  val HptwRespArbCachePort = 0
427  val HptwRespArbHptw = 0
428  hptw_resp_arb.io.in(HptwRespArbCachePort).valid := cache.io.resp.valid && cache.io.resp.bits.hit && cache.io.resp.bits.isHptw
429  hptw_resp_arb.io.in(HptwRespArbCachePort).bits.id := cache.io.resp.bits.toHptw.id
430  hptw_resp_arb.io.in(HptwRespArbCachePort).bits.resp := cache.io.resp.bits.toHptw.resp
431  hptw_resp_arb.io.in(HptwRespArbHptw).valid := hptw.io.resp.valid
432  hptw_resp_arb.io.in(HptwRespArbHptw).bits.id := hptw.io.resp.bits.id
433  hptw_resp_arb.io.in(HptwRespArbHptw).bits.resp := hptw.io.resp.bits.resp
434
435  ptw.io.hptw.resp.valid := hptw_resp_arb.io.out.valid && hptw_resp_arb.io.out.bits.id === FsmReqID.U
436  ptw.io.hptw.resp.bits.h_resp := hptw_resp_arb.io.out.bits.resp
437  llptw.io.hptw.resp.valid := hptw_resp_arb.io.out.valid && hptw_resp_arb.io.out.bits.id =/= FsmReqID.U
438  llptw.io.hptw.resp.bits.h_resp := hptw_resp_arb.io.out.bits.resp
439
440  // Timing: Maybe need to do some optimization or even add one more cycle
441  for (i <- 0 until PtwWidth) {
442    mergeArb(i).in(outArbCachePort).valid := cache.io.resp.valid && cache.io.resp.bits.hit && cache.io.resp.bits.req_info.source===i.U
443    mergeArb(i).in(outArbCachePort).bits.s2xlate := cache.io.resp.bits.req_info.s2xlate
444    mergeArb(i).in(outArbCachePort).bits.s1Resp := cache.io.resp.bits.toTlb
445    mergeArb(i).in(outArbCachePort).bits.s2Resp := cache.io.resp.bits.toHptw.resp
446    mergeArb(i).in(outArbFsmPort).valid := ptw.io.resp.valid && ptw.io.resp.bits.source===i.U
447    mergeArb(i).in(outArbFsmPort).bits.s2xlate := ptw.io.resp.bits.s2xlate
448    mergeArb(i).in(outArbFsmPort).bits.s1Resp := ptw.io.resp.bits.resp
449    mergeArb(i).in(outArbFsmPort).bits.s2Resp := ptw.io.resp.bits.h_resp
450    mergeArb(i).in(outArbMqPort).valid := llptw_out.valid && llptw_out.bits.req_info.source===i.U
451    mergeArb(i).in(outArbMqPort).bits.s2xlate := llptw_out.bits.req_info.s2xlate
452    mergeArb(i).in(outArbMqPort).bits.s1Resp := contiguous_pte_to_merge_ptwResp(resp_pte_sector(llptw_out.bits.id).asUInt, llptw_out.bits.req_info.vpn, llptw_out.bits.af, true)
453    mergeArb(i).in(outArbMqPort).bits.s2Resp := llptw_out.bits.h_resp
454    mergeArb(i).out.ready := outArb(i).in(0).ready
455  }
456
457  for (i <- 0 until PtwWidth) {
458    outArb(i).in(0).valid := mergeArb(i).out.valid
459    outArb(i).in(0).bits.s1Resp := merge_ptwResp_to_sector_ptwResp(mergeArb(i).out.bits.s1Resp)
460    outArb(i).in(0).bits.s2Resp := mergeArb(i).out.bits.s2Resp
461  }
462
463  // io.tlb.map(_.resp) <> outArb.map(_.out)
464  io.tlb.map(_.resp).zip(outArb.map(_.out)).map{
465    case (resp, out) => resp <> out
466  }
467
468  // sfence
469  when (flush) {
470    for (i <- 0 until MemReqWidth) {
471      when (waiting_resp(i)) {
472        flush_latch(i) := true.B
473      }
474    }
475  }
476  // mem -> control signal
477  // waiting_resp and sfence_latch will be reset when mem_resp_done
478  when (mem_resp_done) {
479    waiting_resp(mem.d.bits.source) := false.B
480    flush_latch(mem.d.bits.source) := false.B
481  }
482
483  def block_decoupled[T <: Data](source: DecoupledIO[T], sink: DecoupledIO[T], block_signal: Bool) = {
484    sink.valid   := source.valid && !block_signal
485    source.ready := sink.ready   && !block_signal
486    sink.bits    := source.bits
487  }
488
489  def get_part(data: Vec[UInt], index: UInt): UInt = {
490    val inner_data = data.asTypeOf(Vec(data.getWidth / XLEN, UInt(XLEN.W)))
491    inner_data(index)
492  }
493
494  // not_super means that this is a normal page
495  // valididx(i) will be all true when super page to be convenient for l1 tlb matching
496  def contiguous_pte_to_merge_ptwResp(pte: UInt, vpn: UInt, af: Bool, af_first: Boolean, not_super: Boolean = true) : PtwMergeResp = {
497    assert(tlbcontiguous == 8, "Only support tlbcontiguous = 8!")
498    val ptw_merge_resp = Wire(new PtwMergeResp())
499    for (i <- 0 until tlbcontiguous) {
500      val pte_in = pte(64 * i + 63, 64 * i).asTypeOf(new PteBundle())
501      val ptw_resp = Wire(new PtwMergeEntry(tagLen = sectorvpnLen, hasPerm = true, hasLevel = true))
502      ptw_resp.ppn := pte_in.ppn(ppnLen - 1, sectortlbwidth)
503      ptw_resp.ppn_low := pte_in.ppn(sectortlbwidth - 1, 0)
504      ptw_resp.level.map(_ := 2.U)
505      ptw_resp.perm.map(_ := pte_in.getPerm())
506      ptw_resp.tag := vpn(vpnLen - 1, sectortlbwidth)
507      ptw_resp.pf := (if (af_first) !af else true.B) && pte_in.isPf(2.U)
508      ptw_resp.af := (if (!af_first) pte_in.isPf(2.U) else true.B) && (af || pte_in.isAf())
509      ptw_resp.v := !ptw_resp.pf
510      ptw_resp.prefetch := DontCare
511      ptw_resp.asid := satp.asid
512      ptw_merge_resp.entry(i) := ptw_resp
513    }
514    ptw_merge_resp.pteidx := UIntToOH(vpn(sectortlbwidth - 1, 0)).asBools
515    ptw_merge_resp.not_super := not_super.B
516    ptw_merge_resp
517  }
518
519  def merge_ptwResp_to_sector_ptwResp(pte: PtwMergeResp) : PtwSectorResp = {
520    assert(tlbcontiguous == 8, "Only support tlbcontiguous = 8!")
521    val ptw_sector_resp = Wire(new PtwSectorResp)
522    ptw_sector_resp.entry.tag := pte.entry(OHToUInt(pte.pteidx)).tag
523    ptw_sector_resp.entry.asid := pte.entry(OHToUInt(pte.pteidx)).asid
524    ptw_sector_resp.entry.ppn := pte.entry(OHToUInt(pte.pteidx)).ppn
525    ptw_sector_resp.entry.perm.map(_ := pte.entry(OHToUInt(pte.pteidx)).perm.getOrElse(0.U.asTypeOf(new PtePermBundle)))
526    ptw_sector_resp.entry.level.map(_ := pte.entry(OHToUInt(pte.pteidx)).level.getOrElse(0.U(2.W)))
527    ptw_sector_resp.entry.prefetch := pte.entry(OHToUInt(pte.pteidx)).prefetch
528    ptw_sector_resp.entry.v := pte.entry(OHToUInt(pte.pteidx)).v
529    ptw_sector_resp.af := pte.entry(OHToUInt(pte.pteidx)).af
530    ptw_sector_resp.pf := pte.entry(OHToUInt(pte.pteidx)).pf
531    ptw_sector_resp.addr_low := OHToUInt(pte.pteidx)
532    ptw_sector_resp.pteidx := pte.pteidx
533    for (i <- 0 until tlbcontiguous) {
534      val ppn_equal = pte.entry(i).ppn === pte.entry(OHToUInt(pte.pteidx)).ppn
535      val perm_equal = pte.entry(i).perm.getOrElse(0.U.asTypeOf(new PtePermBundle)).asUInt === pte.entry(OHToUInt(pte.pteidx)).perm.getOrElse(0.U.asTypeOf(new PtePermBundle)).asUInt
536      val v_equal = pte.entry(i).v === pte.entry(OHToUInt(pte.pteidx)).v
537      val af_equal = pte.entry(i).af === pte.entry(OHToUInt(pte.pteidx)).af
538      val pf_equal = pte.entry(i).pf === pte.entry(OHToUInt(pte.pteidx)).pf
539      ptw_sector_resp.valididx(i) := (ppn_equal && perm_equal && v_equal && af_equal && pf_equal) || !pte.not_super
540      ptw_sector_resp.ppn_low(i) := pte.entry(i).ppn_low
541    }
542    ptw_sector_resp.valididx(OHToUInt(pte.pteidx)) := true.B
543    ptw_sector_resp
544  }
545
546  def outReady(source: UInt, port: Int): Bool = {
547    MuxLookup(source, true.B)((0 until PtwWidth).map(i => i.U -> mergeArb(i).in(port).ready))
548  }
549
550  // debug info
551  for (i <- 0 until PtwWidth) {
552    XSDebug(p"[io.tlb(${i.U})] ${io.tlb(i)}\n")
553  }
554  XSDebug(p"[sfence] ${io.sfence}\n")
555  XSDebug(p"[io.csr.tlb] ${io.csr.tlb}\n")
556
557  for (i <- 0 until PtwWidth) {
558    XSPerfAccumulate(s"req_count${i}", io.tlb(i).req(0).fire)
559    XSPerfAccumulate(s"req_blocked_count_${i}", io.tlb(i).req(0).valid && !io.tlb(i).req(0).ready)
560  }
561  XSPerfAccumulate(s"req_blocked_by_mq", arb1.io.out.valid && missQueue.io.out.valid)
562  for (i <- 0 until (MemReqWidth + 1)) {
563    XSPerfAccumulate(s"mem_req_util${i}", PopCount(waiting_resp) === i.U)
564  }
565  XSPerfAccumulate("mem_cycle", PopCount(waiting_resp) =/= 0.U)
566  XSPerfAccumulate("mem_count", mem.a.fire)
567  for (i <- 0 until PtwWidth) {
568    XSPerfAccumulate(s"llptw_ppn_af${i}", mergeArb(i).in(outArbMqPort).valid && mergeArb(i).in(outArbMqPort).bits.s1Resp.entry(OHToUInt(mergeArb(i).in(outArbMqPort).bits.s1Resp.pteidx)).af && !llptw_out.bits.af)
569    XSPerfAccumulate(s"access_fault${i}", io.tlb(i).resp.fire && io.tlb(i).resp.bits.s1.af)
570  }
571
572  // print configs
573  println(s"${l2tlbParams.name}: a ptw, a llptw with size ${l2tlbParams.llptwsize}, miss queue size ${MissQueueSize} l1:${l2tlbParams.l1Size} fa l2: nSets ${l2tlbParams.l2nSets} nWays ${l2tlbParams.l2nWays} l3: ${l2tlbParams.l3nSets} nWays ${l2tlbParams.l3nWays} blockBytes:${l2tlbParams.blockBytes}")
574
575  // time out assert
576  for (i <- 0 until MemReqWidth) {
577    TimeOutAssert(waiting_resp(i), timeOutThreshold, s"ptw mem resp time out wait_resp${i}")
578    TimeOutAssert(flush_latch(i), timeOutThreshold, s"ptw mem resp time out flush_latch${i}")
579  }
580
581
582  val perfEvents  = Seq(llptw, cache, ptw).flatMap(_.getPerfEvents)
583  generatePerfEvent()
584
585  val isWriteL1TlbTable = WireInit(Constantin.createRecord("isWriteL1TlbTable" + p(XSCoreParamsKey).HartId.toString))
586  val L1TlbTable = ChiselDB.createTable("L1Tlb_hart" + p(XSCoreParamsKey).HartId.toString, new L1TlbDB)
587  val ITlbReqDB, DTlbReqDB, ITlbRespDB, DTlbRespDB = Wire(new L1TlbDB)
588  ITlbReqDB.vpn := io.tlb(0).req(0).bits.vpn
589  DTlbReqDB.vpn := io.tlb(1).req(0).bits.vpn
590  ITlbRespDB.vpn := io.tlb(0).resp.bits.s1.entry.tag
591  DTlbRespDB.vpn := io.tlb(1).resp.bits.s1.entry.tag
592  L1TlbTable.log(ITlbReqDB, isWriteL1TlbTable.orR && io.tlb(0).req(0).fire, "ITlbReq", clock, reset)
593  L1TlbTable.log(DTlbReqDB, isWriteL1TlbTable.orR && io.tlb(1).req(0).fire, "DTlbReq", clock, reset)
594  L1TlbTable.log(ITlbRespDB, isWriteL1TlbTable.orR && io.tlb(0).resp.fire, "ITlbResp", clock, reset)
595  L1TlbTable.log(DTlbRespDB, isWriteL1TlbTable.orR && io.tlb(1).resp.fire, "DTlbResp", clock, reset)
596
597  val isWritePageCacheTable = WireInit(Constantin.createRecord("isWritePageCacheTable" + p(XSCoreParamsKey).HartId.toString))
598  val PageCacheTable = ChiselDB.createTable("PageCache_hart" + p(XSCoreParamsKey).HartId.toString, new PageCacheDB)
599  val PageCacheDB = Wire(new PageCacheDB)
600  PageCacheDB.vpn := Cat(cache.io.resp.bits.toTlb.entry(0).tag, OHToUInt(cache.io.resp.bits.toTlb.pteidx))
601  PageCacheDB.source := cache.io.resp.bits.req_info.source
602  PageCacheDB.bypassed := cache.io.resp.bits.bypassed
603  PageCacheDB.is_first := cache.io.resp.bits.isFirst
604  PageCacheDB.prefetched := cache.io.resp.bits.toTlb.entry(0).prefetch
605  PageCacheDB.prefetch := cache.io.resp.bits.prefetch
606  PageCacheDB.l2Hit := cache.io.resp.bits.toFsm.l2Hit
607  PageCacheDB.l1Hit := cache.io.resp.bits.toFsm.l1Hit
608  PageCacheDB.hit := cache.io.resp.bits.hit
609  PageCacheTable.log(PageCacheDB, isWritePageCacheTable.orR && cache.io.resp.fire, "PageCache", clock, reset)
610
611  val isWritePTWTable = WireInit(Constantin.createRecord("isWritePTWTable" + p(XSCoreParamsKey).HartId.toString))
612  val PTWTable = ChiselDB.createTable("PTW_hart" + p(XSCoreParamsKey).HartId.toString, new PTWDB)
613  val PTWReqDB, PTWRespDB, LLPTWReqDB, LLPTWRespDB = Wire(new PTWDB)
614  PTWReqDB.vpn := ptw.io.req.bits.req_info.vpn
615  PTWReqDB.source := ptw.io.req.bits.req_info.source
616  PTWRespDB.vpn := ptw.io.refill.req_info.vpn
617  PTWRespDB.source := ptw.io.refill.req_info.source
618  LLPTWReqDB.vpn := llptw.io.in.bits.req_info.vpn
619  LLPTWReqDB.source := llptw.io.in.bits.req_info.source
620  LLPTWRespDB.vpn := llptw.io.mem.refill.vpn
621  LLPTWRespDB.source := llptw.io.mem.refill.source
622  PTWTable.log(PTWReqDB, isWritePTWTable.orR && ptw.io.req.fire, "PTWReq", clock, reset)
623  PTWTable.log(PTWRespDB, isWritePTWTable.orR && ptw.io.mem.resp.fire, "PTWResp", clock, reset)
624  PTWTable.log(LLPTWReqDB, isWritePTWTable.orR && llptw.io.in.fire, "LLPTWReq", clock, reset)
625  PTWTable.log(LLPTWRespDB, isWritePTWTable.orR && llptw.io.mem.resp.fire, "LLPTWResp", clock, reset)
626
627  val isWriteL2TlbMissQueueTable = WireInit(Constantin.createRecord("isWriteL2TlbMissQueueTable" + p(XSCoreParamsKey).HartId.toString))
628  val L2TlbMissQueueTable = ChiselDB.createTable("L2TlbMissQueue_hart" + p(XSCoreParamsKey).HartId.toString, new L2TlbMissQueueDB)
629  val L2TlbMissQueueInDB, L2TlbMissQueueOutDB = Wire(new L2TlbMissQueueDB)
630  L2TlbMissQueueInDB.vpn := missQueue.io.in.bits.vpn
631  L2TlbMissQueueOutDB.vpn := missQueue.io.out.bits.vpn
632  L2TlbMissQueueTable.log(L2TlbMissQueueInDB, isWriteL2TlbMissQueueTable.orR && missQueue.io.in.fire, "L2TlbMissQueueIn", clock, reset)
633  L2TlbMissQueueTable.log(L2TlbMissQueueOutDB, isWriteL2TlbMissQueueTable.orR && missQueue.io.out.fire, "L2TlbMissQueueOut", clock, reset)
634}
635
636/** BlockHelper, block missqueue, not to send too many req to cache
637 *  Parameter:
638 *    enable: enable BlockHelper, mq should not send too many reqs
639 *    start: when miss queue out fire and need, block miss queue's out
640 *    block: block miss queue's out
641 *    latency: last missqueue out's cache access latency
642 */
643class BlockHelper(latency: Int)(implicit p: Parameters) extends XSModule {
644  val io = IO(new Bundle {
645    val enable = Input(Bool())
646    val start = Input(Bool())
647    val block = Output(Bool())
648  })
649
650  val count = RegInit(0.U(log2Ceil(latency).W))
651  val valid = RegInit(false.B)
652  val work = RegInit(true.B)
653
654  io.block := valid
655
656  when (io.start && work) { valid := true.B }
657  when (valid) { count := count + 1.U }
658  when (count === (latency.U) || io.enable) {
659    valid := false.B
660    work := io.enable
661    count := 0.U
662  }
663}
664
665class PTEHelper() extends ExtModule {
666  val clock  = IO(Input(Clock()))
667  val enable = IO(Input(Bool()))
668  val satp   = IO(Input(UInt(64.W)))
669  val vpn    = IO(Input(UInt(64.W)))
670  val pte    = IO(Output(UInt(64.W)))
671  val level  = IO(Output(UInt(8.W)))
672  val pf     = IO(Output(UInt(8.W)))
673}
674
675class PTWDelayN[T <: Data](gen: T, n: Int, flush: Bool) extends Module {
676  val io = IO(new Bundle() {
677    val in = Input(gen)
678    val out = Output(gen)
679    val ptwflush = Input(flush.cloneType)
680  })
681  val out = RegInit(VecInit(Seq.fill(n)(0.U.asTypeOf(gen))))
682  val t = RegInit(VecInit(Seq.fill(n)(0.U.asTypeOf(gen))))
683  out(0) := io.in
684  if (n == 1) {
685    io.out := out(0)
686  } else {
687    when (io.ptwflush) {
688      for (i <- 0 until n) {
689        t(i) := 0.U.asTypeOf(gen)
690        out(i) := 0.U.asTypeOf(gen)
691      }
692      io.out := 0.U.asTypeOf(gen)
693    } .otherwise {
694      for (i <- 1 until n) {
695        t(i-1) := out(i-1)
696        out(i) := t(i-1)
697      }
698      io.out := out(n-1)
699    }
700  }
701}
702
703object PTWDelayN {
704  def apply[T <: Data](in: T, n: Int, flush: Bool): T = {
705    val delay = Module(new PTWDelayN(in.cloneType, n, flush))
706    delay.io.in := in
707    delay.io.ptwflush := flush
708    delay.io.out
709  }
710}
711
712class FakePTW()(implicit p: Parameters) extends XSModule with HasPtwConst {
713  val io = IO(new L2TLBIO)
714  val flush = VecInit(Seq.fill(PtwWidth)(false.B))
715  flush(0) := DelayN(io.sfence.valid || io.csr.tlb.satp.changed, itlbParams.fenceDelay)
716  flush(1) := DelayN(io.sfence.valid || io.csr.tlb.satp.changed, ldtlbParams.fenceDelay)
717  for (i <- 0 until PtwWidth) {
718    val helper = Module(new PTEHelper())
719    helper.clock := clock
720    helper.satp := io.csr.tlb.satp.ppn
721
722    if (coreParams.softPTWDelay == 1) {
723      helper.enable := io.tlb(i).req(0).fire
724      helper.vpn := io.tlb(i).req(0).bits.vpn
725    } else {
726      helper.enable := PTWDelayN(io.tlb(i).req(0).fire, coreParams.softPTWDelay - 1, flush(i))
727      helper.vpn := PTWDelayN(io.tlb(i).req(0).bits.vpn, coreParams.softPTWDelay - 1, flush(i))
728    }
729
730    val pte = helper.pte.asTypeOf(new PteBundle)
731    val level = helper.level
732    val pf = helper.pf
733    val empty = RegInit(true.B)
734    when (io.tlb(i).req(0).fire) {
735      empty := false.B
736    } .elsewhen (io.tlb(i).resp.fire || flush(i)) {
737      empty := true.B
738    }
739
740    io.tlb(i).req(0).ready := empty || io.tlb(i).resp.fire
741    io.tlb(i).resp.valid := PTWDelayN(io.tlb(i).req(0).fire, coreParams.softPTWDelay, flush(i))
742    assert(!io.tlb(i).resp.valid || io.tlb(i).resp.ready)
743    io.tlb(i).resp.bits.s1.entry.tag := PTWDelayN(io.tlb(i).req(0).bits.vpn, coreParams.softPTWDelay, flush(i))
744    io.tlb(i).resp.bits.s1.entry.ppn := pte.ppn
745    io.tlb(i).resp.bits.s1.entry.perm.map(_ := pte.getPerm())
746    io.tlb(i).resp.bits.s1.entry.level.map(_ := level)
747    io.tlb(i).resp.bits.s1.pf := pf
748    io.tlb(i).resp.bits.s1.af := DontCare // TODO: implement it
749    io.tlb(i).resp.bits.s1.entry.v := !pf
750    io.tlb(i).resp.bits.s1.entry.prefetch := DontCare
751    io.tlb(i).resp.bits.s1.entry.asid := io.csr.tlb.satp.asid
752  }
753}
754
755class L2TLBWrapper()(implicit p: Parameters) extends LazyModule with HasXSParameter {
756  override def shouldBeInlined: Boolean = false
757  val useSoftPTW = coreParams.softPTW
758  val node = if (!useSoftPTW) TLIdentityNode() else null
759  val ptw = if (!useSoftPTW) LazyModule(new L2TLB()) else null
760  if (!useSoftPTW) {
761    node := ptw.node
762  }
763
764  class L2TLBWrapperImp(wrapper: LazyModule) extends LazyModuleImp(wrapper) with HasPerfEvents {
765    val io = IO(new L2TLBIO)
766    val perfEvents = if (useSoftPTW) {
767      val fake_ptw = Module(new FakePTW())
768      io <> fake_ptw.io
769      Seq()
770    }
771    else {
772        io <> ptw.module.io
773        ptw.module.getPerfEvents
774    }
775    generatePerfEvent()
776  }
777
778  lazy val module = new L2TLBWrapperImp(this)
779}
780