Files
eb001/src/main/scala/backBoard/ebus/CDRIn.scala
2025-01-17 16:21:46 +08:00

196 lines
6.4 KiB
Scala

package BACK
import chisel3._
import chisel3.util._
//work in 100MHZ
class CDRInIO extends Bundle{
val axis = Decoupled(new AXIS_Bundle(8))
val serDat = Input(Bool())
val overCLK = Input(Bool())
}
abstract class CDRInBase extends Module{
def sampleRate: Int = 4
require( sampleRate == 4 )
val io: CDRInIO = IO(new CDRInIO)
}
trait CDRInOverSample{ this: CDRInBase =>
val sampleReg = withClockAndReset(io.overCLK.asClock, reset.asBool){ ShiftRegisters( RegNext(io.serDat), sampleRate ) }
// val arbShiftData = for( i <- 0 until sampleRate ) yield { RegInit(0.U(24.W)) }
// val arbSel = Reg(UInt( log2Ceil(sampleRate).W ))
// val isArbLock = RegInit(false.B)
// for( i <- 0 until sampleRate ){
// arbShiftData(i) := Cat( arbShiftData(i)(22,0), RegNext(sampleReg(i)) )
// when( arbShiftData(i) === "h5A5A5A".U & ~isArbLock ){
// isArbLock := true.B
// arbSel := i.U
// }
// }
// when( ( 0 until sampleRate ).map{ i => (arbShiftData(i) === 0.U) }.reduce(_&_) ){
// isArbLock := false.B
// }
// val syncSerDat =
// Mux1H( (0 until sampleRate).map{ i => (( arbSel === i.U ) -> ShiftRegister( sampleReg(i), 2) ) } )
val arbCnt = withClockAndReset(io.overCLK.asClock, reset.asBool){ RegInit("b0001".U(sampleRate.W)) }
arbCnt := Cat( arbCnt(2,0), arbCnt.extract(3) )
val arbLock = withClockAndReset(io.overCLK.asClock, reset.asBool){ Reg(UInt( sampleRate.W )) }
when( sampleReg(0) ^ sampleReg(1) ){
arbLock := arbCnt
}
val asyncSerDat = Mux1H(Seq(
(arbLock === "b0001".U & arbCnt === "b0001".U) -> sampleReg(3),
(arbLock === "b0001".U & arbCnt === "b0010".U) -> sampleReg(0),
(arbLock === "b0001".U & arbCnt === "b0100".U) -> sampleReg(1),
(arbLock === "b0001".U & arbCnt === "b1000".U) -> sampleReg(2),
(arbLock === "b0010".U & arbCnt === "b0001".U) -> sampleReg(2),
(arbLock === "b0010".U & arbCnt === "b0010".U) -> sampleReg(3),
(arbLock === "b0010".U & arbCnt === "b0100".U) -> sampleReg(0),
(arbLock === "b0010".U & arbCnt === "b1000".U) -> sampleReg(1),
(arbLock === "b0100".U & arbCnt === "b0001".U) -> sampleReg(1),
(arbLock === "b0100".U & arbCnt === "b0010".U) -> sampleReg(2),
(arbLock === "b0100".U & arbCnt === "b0100".U) -> sampleReg(3),
(arbLock === "b0100".U & arbCnt === "b1000".U) -> sampleReg(0),
(arbLock === "b1000".U & arbCnt === "b0001".U) -> sampleReg(0),
(arbLock === "b1000".U & arbCnt === "b0010".U) -> sampleReg(1),
(arbLock === "b1000".U & arbCnt === "b0100".U) -> sampleReg(2),
(arbLock === "b1000".U & arbCnt === "b1000".U) -> sampleReg(3),
))
val syncSerDat = ShiftRegister( asyncSerDat, 2 )
}
trait CDRInAxis{ this: CDRInBase =>
def HeaderByte: Int = 8
val ETH_PRE = "h55".U(8.W)
val ETH_SFD = "hD5".U(8.W)
val STATE_IDLE = 0.U
val STATE_HEADER = 1.U
val STATE_PAYLOAD = 2.U
val STATE_CRC = 3.U
val stateNext = Wire(UInt(2.W))
val stateCurr = RegNext( stateNext, STATE_IDLE )
val crcUnit = Module(new crc32_8)
val crcOut = crcUnit.io.crc
val crcCmp = Reg(UInt(32.W))
val bitCnt = Reg(UInt(4.W))
val byteCnt = RegInit(0.U(12.W))
val syncSerDat: Bool
val checkSFD = RegInit( 0.U(20.W) ); checkSFD := Cat( checkSFD(18,0), syncSerDat )
val shiftData = Dualb4b5Decoder(checkSFD(9,0))
val payloadLen = Reg(UInt(12.W))
when( byteCnt === 0.U & bitCnt === 9.U & stateCurr === STATE_HEADER ){
payloadLen := Cat( shiftData, 0.U(4.W) )
} .elsewhen( byteCnt === 1.U & bitCnt === 9.U & stateCurr === STATE_HEADER ){
payloadLen := Cat( payloadLen(11,4), shiftData(7,4) )
}
stateNext :=
Mux1H(Seq(
(stateCurr === STATE_IDLE) -> ( Mux( checkSFD === Cat(Dualb4b5Encoder(ETH_PRE) , Dualb4b5Encoder(ETH_SFD)), STATE_HEADER, STATE_IDLE )), //IDLE
(stateCurr === STATE_HEADER) -> ( Mux( (byteCnt === (HeaderByte-1).U) & (bitCnt === 9.U), STATE_PAYLOAD, STATE_HEADER ) ),
(stateCurr === STATE_PAYLOAD) -> ( Mux( (byteCnt === (payloadLen-1.U) ) & (bitCnt === 9.U), STATE_CRC, STATE_PAYLOAD )), // PAYLOAD
(stateCurr === STATE_CRC) -> ( Mux( (byteCnt === 3.U) & (bitCnt === 9.U), STATE_IDLE, STATE_CRC )), //CRC
))
when( stateCurr === STATE_IDLE & ( checkSFD === Cat(Dualb4b5Encoder(ETH_PRE) , Dualb4b5Encoder(ETH_SFD)) ) ){ //first align
bitCnt := 0.U
} .otherwise{
when( bitCnt === 9.U ){
bitCnt := 0.U
} .otherwise{
bitCnt := bitCnt + 1.U
}
}
when( stateCurr === STATE_IDLE & ( checkSFD === Cat(Dualb4b5Encoder(ETH_PRE) , Dualb4b5Encoder(ETH_SFD)) ) ){ //first align
byteCnt := 0.U
} .elsewhen( bitCnt === 9.U ){
when( stateCurr === STATE_HEADER ){
byteCnt := Mux( byteCnt =/= (HeaderByte-1).U, byteCnt + 1.U, 0.U )
assert( byteCnt <= (HeaderByte-1).U )
} .elsewhen( stateCurr === STATE_PAYLOAD ){
byteCnt := Mux( byteCnt =/= (payloadLen-1.U), byteCnt + 1.U, 0.U )
assert( byteCnt <= ( payloadLen-1.U ) )
} .elsewhen( stateCurr === STATE_CRC ){
byteCnt := Mux( byteCnt =/= 3.U, byteCnt + 1.U, 0.U )
assert( byteCnt <= 3.U )
}
}
val axis_valid = RegInit(false.B)
val axis_tdata = RegEnable( shiftData, bitCnt === 9.U & ( stateCurr === STATE_HEADER | stateCurr === STATE_PAYLOAD | stateCurr === STATE_CRC ) )
val axis_tuser = RegEnable( stateCurr === STATE_CRC & byteCnt === 3.U & (crcOut =/= ~Cat( shiftData, crcCmp(31,8) )), bitCnt === 9.U )
val axis_tlast = RegEnable( stateCurr === STATE_CRC & byteCnt === 3.U, bitCnt === 9.U )
io.axis.valid := axis_valid
io.axis.bits.tdata := axis_tdata
io.axis.bits.tuser := axis_tuser
io.axis.bits.tlast := axis_tlast
when( io.axis.fire ){
axis_valid := false.B
} .elsewhen( bitCnt === 9.U & ( stateCurr === STATE_HEADER | stateCurr === STATE_PAYLOAD | stateCurr === STATE_CRC ) ){
axis_valid := true.B
}
when( stateCurr === STATE_CRC & bitCnt === 9.U ){
crcCmp := Cat( shiftData, crcCmp(31,8) )
}
crcUnit.io.isEnable := ((stateCurr === STATE_HEADER ) | (stateCurr === STATE_PAYLOAD )) & ( bitCnt === 9.U )
crcUnit.io.dataIn := shiftData
crcUnit.reset := reset.asBool | ( stateCurr === STATE_IDLE ) //idle
}
class CDRIn extends CDRInBase with CDRInOverSample with CDRInAxis