feat: 增加TLB，通过si-p测试

2024-01-17 13:00:01 +08:00 · 2024-01-17 13:00:01 +08:00 · 4e300502db
parent 404e0d64e6
commit 4e300502db
4 changed files with 48 additions and 39 deletions
--- a/chisel/difftest
+++ b/chisel/difftest
@ -1 +1 @@
-Subproject commit e89bb7ff9246a977b7e7ded2b611739e1246d33d
+Subproject commit ef0f84099590846759803b50a8fa0cf256470361
--- a/chisel/playground/src/cache/DCache.scala
+++ b/chisel/playground/src/cache/DCache.scala
@ -79,8 +79,8 @@ class DCache(cacheConfig: CacheConfig)(implicit cpuConfig: CpuConfig) extends Mo
  val state                                                                         = RegInit(s_idle)

  // ptw的状态机
-  val pte_handshake :: pte_send :: ptw_uncached :: ptw_cached :: pte_check :: pte_set :: Nil = Enum(6)
-  val ptw_state                                                                              = RegInit(pte_handshake)
+  val ptw_handshake :: ptw_send :: ptw_cached :: ptw_uncached :: ptw_check :: ptw_set :: Nil = Enum(6)
+  val ptw_state                                                                              = RegInit(ptw_handshake)

  // 临时寄存器
  val ptw_scratch = RegInit(0.U.asTypeOf(new Bundle {
@ -103,6 +103,11 @@ class DCache(cacheConfig: CacheConfig)(implicit cpuConfig: CpuConfig) extends Mo
    val offset = UInt(offsetWidth.W)
  }

+  def bankAddr = new Bundle {
+    val index  = UInt(bankIndexWidth.W)
+    val offset = UInt(bankOffsetWidth.W)
+  }
+
  // exe级的index，用于访问第i行的数据
  val exe_index = io.cpu.exe_addr(indexWidth + offsetWidth - 1, offsetWidth)
  // mem级的bank的index，用于访问第i个bank的数据
@ -361,7 +366,7 @@ class DCache(cacheConfig: CacheConfig)(implicit cpuConfig: CpuConfig) extends Mo
          }
        }
      }.otherwise {
-        io.cpu.tlb.ptw.vpn.ready := ptw_state === pte_handshake
+        io.cpu.tlb.ptw.vpn.ready := ptw_state === ptw_handshake
        when(io.cpu.fence_i) {
          // fence.i 需要将所有脏位为true的行写回
          when(dirty.asUInt.orR) {
@ -477,9 +482,10 @@ class DCache(cacheConfig: CacheConfig)(implicit cpuConfig: CpuConfig) extends Mo
          ) {
            valid(replace_index)(replace_way) := true.B
            do_replace                        := false.B
-            when(ptw_scratch.working) {
-              state               := s_tlb_refill
-              ptw_scratch.replace := false.B
+            ptw_scratch.replace               := false.B
+            when(ptw_scratch.working && io.cpu.tlb.ptw.access_type =/= AccessType.fetch) {
+              // ptw复用的模式
+              state := s_tlb_refill
            }.otherwise {
              state := s_idle
            }
@ -525,7 +531,7 @@ class DCache(cacheConfig: CacheConfig)(implicit cpuConfig: CpuConfig) extends Mo
      }
    }
    is(s_tlb_refill) {
-      io.cpu.tlb.ptw.vpn.ready := ptw_state === pte_handshake
+      io.cpu.tlb.ptw.vpn.ready := ptw_state === ptw_handshake
      when(io.cpu.tlb.access_fault) {
        access_fault := true.B
        state        := s_wait
@ -563,7 +569,7 @@ class DCache(cacheConfig: CacheConfig)(implicit cpuConfig: CpuConfig) extends Mo
  def raisePageFault(): Unit = {
    io.cpu.tlb.ptw.pte.valid           := true.B
    io.cpu.tlb.ptw.pte.bits.page_fault := true.B
-    ptw_state                          := pte_handshake
+    ptw_state                          := ptw_handshake
  }

  def modeCheck(): Unit = {
@ -572,30 +578,30 @@ class DCache(cacheConfig: CacheConfig)(implicit cpuConfig: CpuConfig) extends Mo
        when(pte.flag.u && !sum) {
          raisePageFault()
        }.otherwise {
-          ptw_state := pte_set
+          ptw_state := ptw_set
        }
      }
      is(ModeU) {
        when(!pte.flag.u) {
          raisePageFault()
        }.otherwise {
-          ptw_state := pte_set
+          ptw_state := ptw_set
        }
      }
    }
  }

  switch(ptw_state) {
-    is(pte_handshake) {
+    is(ptw_handshake) {
      // 页表访问虚地址握手
      when(io.cpu.tlb.ptw.vpn.valid) {
        vpn_index           := (level - 1).U
        ppn                 := satp.ppn
-        ptw_state           := pte_send
+        ptw_state           := ptw_send
        ptw_scratch.working := true.B
      }
    }
-    is(pte_send) {
+    is(ptw_send) {
      val vpnn = Mux1H(
        Seq(
          (vpn_index === 0.U) -> vpn.vpn0,
@ -621,33 +627,35 @@ class DCache(cacheConfig: CacheConfig)(implicit cpuConfig: CpuConfig) extends Mo
      }
    }
    is(ptw_cached) {
+      bank_raddr            := ptw_scratch.paddr.index
+      tagRam.map(_.io.raddr := ptw_scratch.paddr.index)
      for { i <- 0 until nway } {
        tag_compare_valid(i) :=
          tag(i) === ptw_scratch.paddr.tag && // tag相同
          valid(ptw_scratch.paddr.index)(i) // cache行有效位为真
      }
-      when(cache_hit) {
-        val pte_temp = data(ptw_scratch.paddr.index)(select_way).asTypeOf(pteBundle)
-        when(!pte_temp.flag.v || !pte_temp.flag.r && pte_temp.flag.w) {
-          raisePageFault()
-        }.otherwise {
-          when(pte_temp.flag.r || pte_temp.flag.x) {
-            // 找到了叶子页
-            pte       := pte_temp
-            ptw_state := pte_check
+      when(!ptw_scratch.replace) {
+        when(cache_hit) {
+          val pte_temp = data(ptw_scratch.paddr.offset.asTypeOf(bankAddr).index)(select_way).asTypeOf(pteBundle)
+          when(!pte_temp.flag.v || !pte_temp.flag.r && pte_temp.flag.w) {
+            raisePageFault()
          }.otherwise {
-            // 该pte指向下一个页表
-            vpn_index := vpn_index - 1.U
-            when(vpn_index - 1.U < 0.U) {
-              raisePageFault()
+            when(pte_temp.flag.r || pte_temp.flag.x) {
+              // 找到了叶子页
+              pte       := pte_temp
+              ptw_state := ptw_check
            }.otherwise {
-              ppn       := pte_temp.ppn
-              ptw_state := pte_send
+              // 该pte指向下一个页表
+              vpn_index := vpn_index - 1.U
+              when(vpn_index - 1.U < 0.U) {
+                raisePageFault()
+              }.otherwise {
+                ppn       := pte_temp.ppn
+                ptw_state := ptw_send
+              }
            }
          }
-        }
-      }.otherwise {
-        when(!ptw_scratch.replace) {
+        }.otherwise {
          ptw_scratch.replace      := true.B
          state                    := s_replace // 直接复用dcache的replace状态机，帮我们进行replace操作
          bank_windex              := 0.U
@ -657,7 +665,6 @@ class DCache(cacheConfig: CacheConfig)(implicit cpuConfig: CpuConfig) extends Mo
            (0 until nbank).map(i => bank_replication(i) := data(i)(select_way))
          }
        }
-        // 进入replace状态机后，会在此处等待，直到cache hit
      }
    }
    is(ptw_uncached) {
@ -673,7 +680,7 @@ class DCache(cacheConfig: CacheConfig)(implicit cpuConfig: CpuConfig) extends Mo
          when(pte_temp.flag.r || pte_temp.flag.x) {
            // 找到了叶子页
            pte       := pte_temp
-            ptw_state := pte_check
+            ptw_state := ptw_check
          }.otherwise {
            // 该pte指向下一个页表
            vpn_index := vpn_index - 1.U
@ -681,13 +688,13 @@ class DCache(cacheConfig: CacheConfig)(implicit cpuConfig: CpuConfig) extends Mo
              raisePageFault()
            }.otherwise {
              ppn       := pte_temp.ppn
-              ptw_state := pte_send
+              ptw_state := ptw_send
            }
          }
        }
      }
    }
-    is(pte_check) {
+    is(ptw_check) {
      // 检查权限
      switch(access_type) {
        is(AccessType.load) {
@ -721,7 +728,7 @@ class DCache(cacheConfig: CacheConfig)(implicit cpuConfig: CpuConfig) extends Mo
        }
      }
    }
-    is(pte_set) {
+    is(ptw_set) {
      when(
        vpn_index > 0.U && (
          vpn_index === 1.U && pte.ppn(0) ||
@ -750,7 +757,7 @@ class DCache(cacheConfig: CacheConfig)(implicit cpuConfig: CpuConfig) extends Mo
        }
        io.cpu.tlb.ptw.pte.bits.entry.ppn := ppn_set.asUInt

-        ptw_state := pte_handshake
+        ptw_state := ptw_handshake
      }
    }
  }
--- a/chisel/playground/src/cache/mmu/Tlb.scala
+++ b/chisel/playground/src/cache/mmu/Tlb.scala
@ -229,6 +229,7 @@ class Tlb extends Module with HasTlbConst with HasCSRConst {
      }
    }
    is(search_pte) {
+      req_ptw(0)              := true.B
      io.dcache.ptw.vpn.valid := true.B
      when(io.dcache.ptw.pte.valid) {
        when(io.dcache.ptw.pte.bits.access_fault) {
@ -330,6 +331,7 @@ class Tlb extends Module with HasTlbConst with HasCSRConst {
      }
    }
    is(search_pte) {
+      req_ptw(1)              := true.B
      io.dcache.ptw.vpn.valid := true.B
      when(io.dcache.ptw.pte.valid) {
        when(io.dcache.ptw.pte.bits.access_fault) {
--- a/chisel/playground/src/pipeline/execute/fu/Csr.scala
+++ b/chisel/playground/src/pipeline/execute/fu/Csr.scala
@ -126,7 +126,7 @@ class Csr(implicit val cpuConfig: CpuConfig) extends Module with HasCSRConst {
  // Supervisor Trap Setup
  // sstatus 状态寄存器，源自mstatus
  val sstatusWmask = "h00000000000c0122".U(XLEN.W)
-  val sstatusRmask = "h80000000000de762".U(XLEN.W)
+  val sstatusRmask = "h80000003000de762".U(XLEN.W)
  // sedeleg 异常代理寄存器，未实现
  // sideleg 中断代理寄存器，未实现
  // sie 中断使能寄存器，源自mie