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JTAG: Add coverage points to the JTAG Tap

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This commit is contained in:
Megan Wachs 2017-10-02 11:05:45 -07:00
parent 723af5e6b6
commit a8ab06d572
3 changed files with 31 additions and 10 deletions
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24
src/main/scala/jtag/JtagShifter.scala
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@ -7,6 +7,9 @@ import chisel3.core.DataMirror
import chisel3.internal.firrtl.KnownWidth
import chisel3.util._
import freechips.rocketchip.config.Parameters
import freechips.rocketchip.util.property._
/** Base JTAG shifter IO, viewed from input to shift register chain.
* Can be chained together.
*/
@ -51,7 +54,7 @@ trait Chain extends Module {
*
* Implements Clause 10.
*/
class JtagBypassChain extends Chain {
class JtagBypassChain(implicit val p: Parameters) extends Chain {
class ModIO extends ChainIO
val io = IO(new ModIO)
io.chainOut chainControlFrom io.chainIn
@ -60,6 +63,8 @@ class JtagBypassChain extends Chain {
io.chainOut.data := reg
cover(io.chainIn.capture, "bypass_chain_capture", "JTAG; bypass_chain_capture; This Bypass Chain captured data")
when (io.chainIn.capture) {
reg := false.B // 10.1.1b capture logic 0 on TCK rising
} .elsewhen (io.chainIn.shift) {
@ -71,7 +76,7 @@ class JtagBypassChain extends Chain {
}
object JtagBypassChain {
def apply() = new JtagBypassChain
def apply()(implicit p: Parameters) = new JtagBypassChain
}
/** Simple shift register with parallel capture only, for read-only data registers.
@ -82,7 +87,7 @@ object JtagBypassChain {
* 7.2.1c shifter shifts on TCK rising edge
* 4.3.2a TDI captured on TCK rising edge, 6.1.2.1b assumed changes on TCK falling edge
*/
class CaptureChain[+T <: Data](gen: T) extends Chain {
class CaptureChain[+T <: Data](gen: T)(implicit val p: Parameters) extends Chain {
class ModIO extends ChainIO {
val capture = Capture(gen)
}
@ -98,6 +103,8 @@ class CaptureChain[+T <: Data](gen: T) extends Chain {
io.chainOut.data := regs(0)
cover(io.chainIn.capture, "chain_capture", "JTAG; chain_capture; This Chain captured data")
when (io.chainIn.capture) {
(0 until n) map (x => regs(x) := io.capture.bits.asUInt()(x))
io.capture.capture := true.B
@ -114,7 +121,7 @@ class CaptureChain[+T <: Data](gen: T) extends Chain {
}
object CaptureChain {
def apply[T <: Data](gen: T) = new CaptureChain(gen)
def apply[T <: Data](gen: T)(implicit p: Parameters) = new CaptureChain(gen)
}
/** Simple shift register with parallel capture and update. Useful for general instruction and data
@ -127,7 +134,7 @@ object CaptureChain {
* 7.2.1c shifter shifts on TCK rising edge
* 4.3.2a TDI captured on TCK rising edge, 6.1.2.1b assumed changes on TCK falling edge
*/
class CaptureUpdateChain[+T <: Data, +V <: Data](genCapture: T, genUpdate: V) extends Chain {
class CaptureUpdateChain[+T <: Data, +V <: Data](genCapture: T, genUpdate: V)(implicit val p: Parameters) extends Chain {
class ModIO extends ChainIO {
val capture = Capture(genCapture)
val update = Valid(genUpdate) // valid high when in update state (single cycle), contents may change any time after
@ -154,6 +161,9 @@ class CaptureUpdateChain[+T <: Data, +V <: Data](genCapture: T, genUpdate: V) ex
val captureBits = io.capture.bits.asUInt()
cover(io.chainIn.capture, "chain_capture", "JTAG;chain_capture; This Chain captured data")
cover(io.chainIn.capture, "chain_update", "JTAG;chain_update; This Chain updated data")
when (io.chainIn.capture) {
(0 until math.min(n, captureWidth)) map (x => regs(x) := captureBits(x))
(captureWidth until n) map (x => regs(x) := 0.U)
@ -179,7 +189,7 @@ class CaptureUpdateChain[+T <: Data, +V <: Data](genCapture: T, genUpdate: V) ex
object CaptureUpdateChain {
/** Capture-update chain with matching capture and update types.
*/
def apply[T <: Data](gen: T) = new CaptureUpdateChain(gen, gen)
def apply[T <: Data, V <: Data](genCapture: T, genUpdate: V) =
def apply[T <: Data](gen: T)(implicit p: Parameters) = new CaptureUpdateChain(gen, gen)
def apply[T <: Data, V <: Data](genCapture: T, genUpdate: V)(implicit p: Parameters) =
new CaptureUpdateChain(genCapture, genUpdate)
}

11
src/main/scala/jtag/JtagStateMachine.scala
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@ -4,7 +4,9 @@ package freechips.rocketchip.jtag
import chisel3._
import chisel3.util._
import freechips.rocketchip.config.{Parameters}
import freechips.rocketchip.util.{AsyncResetRegVec}
import freechips.rocketchip.util.property._
object JtagState {
sealed abstract class State(val id: Int) {
@ -67,7 +69,7 @@ object JtagState {
*
*
*/
class JtagStateMachine extends Module(override_reset=Some(false.B)) {
class JtagStateMachine(implicit val p: Parameters) extends Module(override_reset=Some(false.B)) {
class StateMachineIO extends Bundle {
val tms = Input(Bool())
val currState = Output(JtagState.State.chiselType())
@ -140,4 +142,11 @@ class JtagStateMachine extends Module(override_reset=Some(false.B)) {
}
io.currState := currState
// Generate Coverate Points
JtagState.State.all.foreach { s =>
cover (currState === s.U && io.tms === true.B, s"${s.toString}_tms_1", "JTAG; ${s.toString} with TMS = 1; State Transition from ${s.toString} with TMS = 1")
cover (currState === s.U && io.tms === false.B, s"${s.toString}_tms_0", "JTAG; ${s.toString} with TMS = 0; State Transition from ${s.toString} with TMS = 0")
}
}

6
src/main/scala/jtag/JtagTap.scala
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@ -4,6 +4,8 @@ package freechips.rocketchip.jtag
import chisel3._
import chisel3.util._
import freechips.rocketchip.config.Parameters
/** JTAG signals, viewed from the master side
*/
class JTAGIO(hasTRSTn: Boolean = false) extends Bundle {
@ -57,7 +59,7 @@ class JtagControllerIO(irLength: Int) extends JtagBlockIO(irLength, false) {
* Misc notes:
* - Figure 6-3 and 6-4 provides examples with timing behavior
*/
class JtagTapController(irLength: Int, initialInstruction: BigInt) extends Module {
class JtagTapController(irLength: Int, initialInstruction: BigInt)(implicit val p: Parameters) extends Module {
require(irLength >= 2) // 7.1.1a
val io = IO(new JtagControllerIO(irLength))
@ -160,7 +162,7 @@ object JtagTapGenerator {
* TODO:
* - support concatenated scan chains
*/
def apply(irLength: Int, instructions: Map[BigInt, Chain], icode: Option[BigInt] = None): JtagBlockIO = {
def apply(irLength: Int, instructions: Map[BigInt, Chain], icode: Option[BigInt] = None)(implicit p: Parameters): JtagBlockIO = {
val internalIo = Wire(new JtagBlockIO(irLength, icode.isDefined))