Initial Commit

1 files changed, 100 insertions, 0 deletions

diff --git a/VexRiscv/src/main/scala/vexriscv/plugin/IntAluPlugin.scala b/VexRiscv/src/main/scala/vexriscv/plugin/IntAluPlugin.scala
new file mode 100644
index 0000000..0520c2f
--- /dev/null
+++ b/VexRiscv/src/main/scala/vexriscv/plugin/IntAluPlugin.scala
@@ -0,0 +1,100 @@
+package vexriscv.plugin
+
+import vexriscv._
+import spinal.core._
+object IntAluPlugin{
+  object AluBitwiseCtrlEnum extends SpinalEnum(binarySequential){
+    val XOR, OR, AND = newElement()
+  }
+  object AluCtrlEnum extends SpinalEnum(binarySequential){
+    val ADD_SUB, SLT_SLTU, BITWISE = newElement()
+  }
+
+  object ALU_BITWISE_CTRL extends Stageable(AluBitwiseCtrlEnum())
+  object ALU_CTRL extends Stageable(AluCtrlEnum())
+}
+
+class IntAluPlugin extends Plugin[VexRiscv]{
+  import IntAluPlugin._
+
+
+  override def setup(pipeline: VexRiscv): Unit = {
+    import Riscv._
+    import pipeline.config._
+
+    val immediateActions = List[(Stageable[_ <: BaseType],Any)](
+      SRC1_CTRL                -> Src1CtrlEnum.RS,
+      SRC2_CTRL                -> Src2CtrlEnum.IMI,
+      REGFILE_WRITE_VALID      -> True,
+      BYPASSABLE_EXECUTE_STAGE -> True,
+      BYPASSABLE_MEMORY_STAGE  -> True,
+      RS1_USE -> True
+    )
+
+    val nonImmediateActions = List[(Stageable[_ <: BaseType],Any)](
+      SRC1_CTRL                -> Src1CtrlEnum.RS,
+      SRC2_CTRL                -> Src2CtrlEnum.RS,
+      REGFILE_WRITE_VALID      -> True,
+      BYPASSABLE_EXECUTE_STAGE -> True,
+      BYPASSABLE_MEMORY_STAGE  -> True,
+      RS1_USE -> True,
+      RS2_USE -> True
+    )
+
+    val otherAction = List[(Stageable[_ <: BaseType],Any)](
+      REGFILE_WRITE_VALID      -> True,
+      BYPASSABLE_EXECUTE_STAGE -> True,
+      BYPASSABLE_MEMORY_STAGE  -> True
+    )
+
+
+
+    val decoderService = pipeline.service(classOf[DecoderService])
+    decoderService.add(List(
+      ADD  -> (nonImmediateActions ++ List(ALU_CTRL -> AluCtrlEnum.ADD_SUB,  SRC_USE_SUB_LESS -> False)),
+      SUB  -> (nonImmediateActions ++ List(ALU_CTRL -> AluCtrlEnum.ADD_SUB,  SRC_USE_SUB_LESS -> True)),
+      SLT  -> (nonImmediateActions ++ List(ALU_CTRL -> AluCtrlEnum.SLT_SLTU, SRC_USE_SUB_LESS -> True, SRC_LESS_UNSIGNED -> False)),
+      SLTU -> (nonImmediateActions ++ List(ALU_CTRL -> AluCtrlEnum.SLT_SLTU, SRC_USE_SUB_LESS -> True, SRC_LESS_UNSIGNED -> True)),
+      XOR  -> (nonImmediateActions ++ List(ALU_CTRL -> AluCtrlEnum.BITWISE,  ALU_BITWISE_CTRL -> AluBitwiseCtrlEnum.XOR)),
+      OR   -> (nonImmediateActions ++ List(ALU_CTRL -> AluCtrlEnum.BITWISE,  ALU_BITWISE_CTRL -> AluBitwiseCtrlEnum.OR)),
+      AND  -> (nonImmediateActions ++ List(ALU_CTRL -> AluCtrlEnum.BITWISE,  ALU_BITWISE_CTRL -> AluBitwiseCtrlEnum.AND))
+    ))
+
+    decoderService.add(List(
+      ADDI  -> (immediateActions ++ List(ALU_CTRL -> AluCtrlEnum.ADD_SUB,  SRC_USE_SUB_LESS -> False)),
+      SLTI  -> (immediateActions ++ List(ALU_CTRL -> AluCtrlEnum.SLT_SLTU, SRC_USE_SUB_LESS -> True, SRC_LESS_UNSIGNED -> False)),
+      SLTIU -> (immediateActions ++ List(ALU_CTRL -> AluCtrlEnum.SLT_SLTU, SRC_USE_SUB_LESS -> True, SRC_LESS_UNSIGNED -> True)),
+      XORI  -> (immediateActions ++ List(ALU_CTRL -> AluCtrlEnum.BITWISE,  ALU_BITWISE_CTRL -> AluBitwiseCtrlEnum.XOR)),
+      ORI   -> (immediateActions ++ List(ALU_CTRL -> AluCtrlEnum.BITWISE,  ALU_BITWISE_CTRL -> AluBitwiseCtrlEnum.OR)),
+      ANDI  -> (immediateActions ++ List(ALU_CTRL -> AluCtrlEnum.BITWISE,  ALU_BITWISE_CTRL -> AluBitwiseCtrlEnum.AND))
+    ))
+
+    decoderService.add(List(
+      LUI   -> (otherAction ++ List(ALU_CTRL -> AluCtrlEnum.ADD_SUB, SRC1_CTRL -> Src1CtrlEnum.IMU, SRC_USE_SUB_LESS -> False, SRC_ADD_ZERO -> True)),
+      AUIPC -> (otherAction ++ List(ALU_CTRL -> AluCtrlEnum.ADD_SUB, SRC_USE_SUB_LESS -> False, SRC1_CTRL -> Src1CtrlEnum.IMU, SRC2_CTRL -> Src2CtrlEnum.PC))
+    ))
+  }
+
+  override def build(pipeline: VexRiscv): Unit = {
+    import pipeline._
+    import pipeline.config._
+
+
+    execute plug new Area{
+      import execute._
+
+      val bitwise = input(ALU_BITWISE_CTRL).mux(
+        AluBitwiseCtrlEnum.AND  -> (input(SRC1) & input(SRC2)),
+        AluBitwiseCtrlEnum.OR   -> (input(SRC1) | input(SRC2)),
+        AluBitwiseCtrlEnum.XOR  -> (input(SRC1) ^ input(SRC2))
+      )
+
+      // mux results
+      insert(REGFILE_WRITE_DATA) := input(ALU_CTRL).mux(
+        AluCtrlEnum.BITWISE  -> bitwise,
+        AluCtrlEnum.SLT_SLTU -> input(SRC_LESS).asBits(32 bit),
+        AluCtrlEnum.ADD_SUB  -> input(SRC_ADD_SUB)
+      )
+    }
+  }
+}