Updated the serdes tester

Author: vikramjain236

src/main/scala/sideband/sidebandNode.scala

@@ -7,8 +7,7 @@ import chisel3.experimental._
 
 import interfaces._
 
-//TODO: 1) L289-290 should be reconsidered
-//      2) SidebandLinkDeserializer needs to have CDC crossings
+//TODO: 1) SidebandLinkDeserializer needs to have CDC crossings
 
 // import freechips.rocketchip.config.Parameters
 import freechips.rocketchip.util._
@@ -318,10 +317,10 @@ class SidebandLinkDeserializer(
 
     val (recvCount, recvDone) = Counter(true.B, dataBeats)
 
-    val recvCount_delay = RegInit(0.U(log2Ceil(dataBeats).W))
-    recvCount_delay := recvCount
+    //val recvCount_delay = RegInit(0.U(log2Ceil(dataBeats).W))
+    //recvCount_delay := recvCount
 
-    data(recvCount_delay) := io.in.bits
+    data(recvCount) := io.in.bits
     when(recvDone) { receiving := false.B }
     when(io.out.fire) { receiving := true.B }
     io.out.valid := !receiving

src/test/scala/sideband/sidebandSerDesTest.scala

@@ -0,0 +1,132 @@
+package edu.berkeley.cs.ucie.digital
+package sideband
+
+import chisel3._
+import chisel3.util._
+import chiseltest._
+import org.scalatest.flatspec.AnyFlatSpec
+
+import interfaces._
+
+class SerDesTester extends AnyFlatSpec with ChiselScalatestTester {
+  behavior of "SerDes"
+  it should "simple serializer sanity" in {
+    test(new SidebandSerializer(new SidebandParams(), new FdiParams(width = 8, dllpWidth = 8, sbWidth = 32))) { c =>
+        // prepare random data generator
+        println("Test started")
+        val seed: Int = 0
+        val rand = new scala.util.Random(seed)
+
+        //init
+        c.io.in.valid.poke(false.B)
+        c.io.out.credit.poke(false.B)
+        c.clock.step()
+
+        //Send data to serializer
+        println("Send data")
+        val data = BigInt(c.msg_w, rand).U
+        c.io.in.valid.poke(true.B)
+        c.io.in.bits.poke(data)
+        c.io.out.valid.expect(false.B)
+        c.clock.step()
+
+        //Check serialized data
+        c.io.in.valid.poke(false.B)
+        for(i <- 0 until (c.msg_w / c.sb_w)){
+          val serialized_data = data((i+1)*c.sb_w-1, i*c.sb_w)
+          c.io.in.ready.expect(false.B)
+          c.io.out.valid.expect(true.B)
+          c.io.out.bits.expect(serialized_data)
+          c.clock.step()
+        }
+
+        //make sure nothing is there
+        c.io.in.ready.expect(true.B)
+        c.io.out.valid.expect(false.B)
+    }
+  }
+
+  it should "simple deserializer sanity" in {
+    test(new SidebandDeserializer(new SidebandParams(), new FdiParams(width = 8, dllpWidth = 8, sbWidth = 32))) { c => 
+      // prepare random data generator
+      println("Test started")
+      val seed: Int = 0
+      val rand = new scala.util.Random(seed)
+
+      //init
+      c.io.in.valid.poke(false.B)
+      c.io.out.ready.poke(false.B)
+      c.clock.step()
+
+      //Send data to deserializer
+      println("Send data")
+      val data = BigInt(c.msg_w, rand).U
+      for(i <- 0 until (c.msg_w / c.sb_w)){
+        c.io.in.valid.poke(true.B)
+        c.io.in.bits.poke(data((i+1)*c.sb_w-1, i*c.sb_w))
+        c.io.out.valid.expect(false.B)
+        c.clock.step()
+      }
+
+      //Check deserialized data and credit return
+      c.io.in.valid.poke(false.B)
+      c.io.out.ready.poke(true.B)
+      c.io.out.valid.expect(true.B)
+      c.io.out.bits.expect(data)
+      //c.io.in.credit.expect(true.B)
+      c.clock.step()
+
+      //make sure nothing is there
+      c.io.out.valid.expect(false.B)
+    }
+  }
+
+  it should "stress serializer sanity" in {
+    test(new SidebandSerializer(new SidebandParams(), new FdiParams(width = 8, dllpWidth = 8, sbWidth = 32))) { c =>
+        // prepare random data generator
+        println("Test started")
+        val seed: Int = 0
+        val rand = new scala.util.Random(seed)
+
+        //init
+        c.io.in.valid.poke(false.B)
+        c.io.out.credit.poke(false.B)
+        c.clock.step()
+
+        //Transfer data 32 times until no credit left
+        for(i <- 0 until c.cdt_max){
+          //Send data to serializer
+          println("Send data")
+          val data = 1.U
+          c.io.in.valid.poke(true.B)
+          c.io.in.bits.poke(data)
+          c.io.out.valid.expect(false.B)
+          c.clock.step()
+
+          //Check serialized data
+          c.io.in.valid.poke(false.B)
+          for(j <- 0 until (c.msg_w / c.sb_w)){
+            val serialized_data = data((j+1)*c.sb_w-1, j*c.sb_w)
+            c.io.in.ready.expect(false.B)
+            c.io.out.valid.expect(true.B)
+            c.io.out.bits.expect(serialized_data)
+            c.clock.step()
+          }
+        }
+
+        //Send data to serializer when no credit
+        println("Send data")
+        val data = 1.U
+        c.io.in.valid.poke(true.B)
+        c.io.in.bits.poke(data)
+        c.io.out.valid.expect(false.B)
+        c.clock.step()
+
+        //Check not send out msg when no credit left
+        c.io.in.valid.poke(false.B)
+        c.io.out.valid.expect(false.B)
+        c.io.in.ready.expect(false.B)
+        c.clock.step()
+    }
+  }
+}