双时钟域FIFO

此示例创建了一个专为跨时钟域而设计的 StreamFifoCC 以及 3 个仿真线程。

线程处理：

• 两个时钟域的管理

• 推入 FIFO

• 从 FIFO 弹出

FIFO 推送线程将输入随机化。

FIFO 弹出线程根据参考模型（普通的 scala.collection.mutable.Queue 实例）检查 DUT 的输出。

import spinal.core._
import spinal.core.sim._

import scala.collection.mutable.Queue


object SimStreamFifoCCExample {
  def main(args: Array[String]): Unit = {
    // Compile the Component for the simulator.
    val compiled = SimConfig.withWave.allOptimisation.compile(
      rtl = new StreamFifoCC(
        dataType = Bits(32 bits),
        depth = 32,
        pushClock = ClockDomain.external("clkA"),
        popClock = ClockDomain.external("clkB",withReset = false)
      )
    )

    // Run the simulation.
    compiled.doSimUntilVoid{dut =>
      val queueModel = mutable.Queue[Long]()

      // Fork a thread to manage the clock domains signals
      val clocksThread = fork {
        // Clear the clock domains' signals, to be sure the simulation captures their first edges.
        dut.pushClock.fallingEdge()
        dut.popClock.fallingEdge()
        dut.pushClock.deassertReset()
        sleep(0)

        // Do the resets.
        dut.pushClock.assertReset()
        sleep(10)
        dut.pushClock.deassertReset()
        sleep(1)

        // Forever, randomly toggle one of the clocks.
        // This will create asynchronous clocks without fixed frequencies.
        while(true) {
          if(Random.nextBoolean()) {
            dut.pushClock.clockToggle()
          } else {
            dut.popClock.clockToggle()
          }
          sleep(1)
        }
      }

      // Push data randomly, and fill the queueModel with pushed transactions.
      val pushThread = fork {
        while(true) {
          dut.io.push.valid.randomize()
          dut.io.push.payload.randomize()
          dut.pushClock.waitSampling()
          if(dut.io.push.valid.toBoolean && dut.io.push.ready.toBoolean) {
            queueModel.enqueue(dut.io.push.payload.toLong)
          }
        }
      }

      // Pop data randomly, and check that it match with the queueModel.
      val popThread = fork {
        for(i <- 0 until 100000) {
          dut.io.pop.ready.randomize()
          dut.popClock.waitSampling()
          if(dut.io.pop.valid.toBoolean && dut.io.pop.ready.toBoolean) {
            assert(dut.io.pop.payload.toLong == queueModel.dequeue())
          }
        }
        simSuccess()
      }
    }
  }
}