refactor: 修改exe级跳转为flush

chisel/playground/src/pipeline/execute/ExecuteUnit.scala

@@ -16,7 +16,7 @@ class ExecuteUnit(implicit val config: CpuConfig) extends Module {
     val csr          = Flipped(new CsrExecuteUnit())
     val bpu          = new ExecuteUnitBranchPredictor()
     val fetchUnit = Output(new Bundle {
-      val branch = Bool()
+      val flush  = Bool()
       val target = UInt(PC_WID.W)
     })
     val decoderUnit = new Bundle {
@@ -57,8 +57,7 @@ class ExecuteUnit(implicit val config: CpuConfig) extends Module {
   io.ctrl.inst(0).reg_waddr := io.executeStage.inst0.info.reg_waddr
   io.ctrl.inst(1).mem_wreg  := io.executeStage.inst1.info.mem_wreg
   io.ctrl.inst(1).reg_waddr := io.executeStage.inst1.info.reg_waddr
-  io.ctrl.branch := valid(0) && io.ctrl.allow_to_go &&
-    (fu.branch.jump_regiser || fu.branch.pred_fail)
+  io.ctrl.branch            := io.fetchUnit.flush
 
   io.csr.in.valid := is_csr.asUInt.orR
   io.csr.in.info := MuxCase(
@@ -116,7 +115,8 @@ class ExecuteUnit(implicit val config: CpuConfig) extends Module {
   io.bpu.branch           := fu.branch.branch
   io.bpu.branch_inst      := io.executeStage.inst0.jb_info.branch_inst
 
-  io.fetchUnit.branch := io.ctrl.branch
+  io.fetchUnit.flush := valid(0) && io.ctrl.allow_to_go &&
+    fu.branch.flush
   io.fetchUnit.target := fu.branch.target
 
   io.ctrl.fu_stall := fu.stall_req
@@ -151,8 +151,8 @@ class ExecuteUnit(implicit val config: CpuConfig) extends Module {
     )
   )
   io.memoryStage.inst0.ex.exception(instrAddrMisaligned) := io.executeStage.inst0.ex.exception(instrAddrMisaligned) ||
-    io.fetchUnit.branch && io.fetchUnit.target(1, 0).orR
-  when(io.fetchUnit.branch && io.fetchUnit.target(1, 0).orR) {
+    io.fetchUnit.flush && io.fetchUnit.target(1, 0).orR
+  when(io.fetchUnit.flush && io.fetchUnit.target(1, 0).orR) {
     io.memoryStage.inst0.ex.tval := io.fetchUnit.target
   }
 
@@ -178,8 +178,8 @@ class ExecuteUnit(implicit val config: CpuConfig) extends Module {
     )
   )
   io.memoryStage.inst1.ex.exception(instrAddrMisaligned) := io.executeStage.inst1.ex.exception(instrAddrMisaligned) ||
-    io.fetchUnit.branch && io.fetchUnit.target(1, 0).orR
-  when(io.fetchUnit.branch && io.fetchUnit.target(1, 0).orR) {
+    io.fetchUnit.flush && io.fetchUnit.target(1, 0).orR
+  when(io.fetchUnit.flush && io.fetchUnit.target(1, 0).orR) {
     io.memoryStage.inst1.ex.tval := io.fetchUnit.target
   }
 

chisel/playground/src/pipeline/execute/Fu.scala

@@ -31,7 +31,7 @@ class Fu(implicit val config: CpuConfig) extends Module {
       val jump_regiser  = Input(Bool())
       val branch_target = Input(UInt(PC_WID.W))
       val branch        = Output(Bool())
-      val pred_fail     = Output(Bool())
+      val flush         = Output(Bool())
       val target        = Output(UInt(PC_WID.W))
     }
   })
@@ -46,7 +46,7 @@ class Fu(implicit val config: CpuConfig) extends Module {
   branchCtrl.in.jump_regiser  := io.branch.jump_regiser
   branchCtrl.in.branch_target := io.branch.branch_target
   io.branch.branch            := branchCtrl.out.branch
-  io.branch.pred_fail         := branchCtrl.out.pred_fail
+  io.branch.flush             := (branchCtrl.out.pred_fail || io.branch.jump_regiser)
   io.branch.target            := branchCtrl.out.target
 
   for (i <- 0 until (config.fuNum)) {

chisel/playground/src/pipeline/fetch/FetchUnit.scala

@@ -5,20 +5,21 @@ import chisel3.util._
 import cpu.defines.Const._
 import cpu.CpuConfig
 
-class FetchUnit(implicit
-    val config: CpuConfig,
-) extends Module {
+class FetchUnit(
+  implicit
+  val config: CpuConfig)
+    extends Module {
   val io = IO(new Bundle {
     val memory = new Bundle {
       val flush  = Input(Bool())
-      val flush_pc = Input(UInt(PC_WID.W))
+      val target = Input(UInt(PC_WID.W))
     }
     val decoder = new Bundle {
       val branch = Input(Bool())
       val target = Input(UInt(PC_WID.W))
     }
     val execute = new Bundle {
-      val branch = Input(Bool())
+      val flush  = Input(Bool())
       val target = Input(UInt(PC_WID.W))
     }
     val instFifo = new Bundle {
@@ -48,10 +49,10 @@ class FetchUnit(implicit
   io.iCache.pc_next := MuxCase(
     pc_next_temp,
     Seq(
-      io.memory.flush   -> io.memory.flush_pc,
-      io.execute.branch -> io.execute.target,
+      io.memory.flush   -> io.memory.target,
+      io.execute.flush  -> io.execute.target,
       io.decoder.branch -> io.decoder.target,
-      io.instFifo.full  -> pc,
-    ),
+      io.instFifo.full  -> pc
+    )
   )
 }

chisel/playground/src/pipeline/memory/MemoryUnit.scala

@@ -15,7 +15,7 @@ class MemoryUnit(implicit val config: CpuConfig) extends Module {
     val memoryStage = Input(new ExecuteUnitMemoryUnit())
     val fetchUnit = Output(new Bundle {
       val flush  = Bool()
-      val flush_pc = UInt(PC_WID.W)
+      val target = UInt(PC_WID.W)
     })
     val decoderUnit    = Output(Vec(config.fuNum, new RegWrite()))
     val csr            = Flipped(new CsrMemoryUnit())
@@ -81,7 +81,7 @@ class MemoryUnit(implicit val config: CpuConfig) extends Module {
   )
 
   io.fetchUnit.flush  := io.csr.out.flush && io.ctrl.allow_to_go
-  io.fetchUnit.flush_pc := Mux(io.csr.out.flush, io.csr.out.flush_pc, io.writeBackStage.inst0.pc + 4.U)
+  io.fetchUnit.target := Mux(io.csr.out.flush, io.csr.out.flush_pc, io.writeBackStage.inst0.pc + 4.U)
 
   io.ctrl.flush_req := io.fetchUnit.flush
 }