In Chisel3, what imports do I need for the Printable examples? - chisel

Question

I am trying to follow the example here:
https://github.com/freechipsproject/chisel3/wiki/Printing-in-Chisel#custom-printing
As in the example, I overrode def toPrintable: Printable with a concatenation of p"..." + strings.
In my scala file I
import chisel3._
But I get Scala compile warnings that it doesn't know what Printable is nor does it know what to do with the p interpolator, which makes me think I don't have the right imports.
Is there something I need to import other than chisel3._?
Here is a bit more information on what I am doing and what error I am getting.
I am modifying this file:
https://github.com/chipsalliance/rocket-chip/blob/e6a6c67f30d668e702ddbef93789e9b4f709b237/src/main/scala/tilelink/Bundles.scala
Here is what I have added:
...
import Chisel._
import chisel3.{Printable}
...
final class TLBundleA(params: TLBundleParameters)
extends TLBundleBase(params) with TLAddrChannel
{
...
override def toPrintable: Printable = {
p"A:\t" +
p"opcode[${opcode}]\t" +
p"param[${param}]\t" +
p"size[${size}]\t" +
p"source[${source}]\t" +
p"address[${address}]\t" +
p"user[${user}]\t" +
p"mask[${mask}]\t" +
p"data[${data}]\t" +
p"corrupt[${corrupt}]\n"
}
}
It seems that (unlike import chisel3._), import.chisel3.{Printable} works, but I am not doing something right with the p"...". I get this series of error:
[error] rocket-chip/src/main/scala/tilelink/Bundles.scala:189:5: value p is not a member of StringContext
[error] p"A:\t" +
[error] ^
[error] rocket-chip/src/main/scala/tilelink/Bundles.scala:190:5: value p is not a member of StringContext
[error] p"opcode[${opcode}]\t" +
[error] ^
...
[error] rocket-chip/src/main/scala/tilelink/Bundles.scala:198:5: value p is not a member of StringContext
[error] p"corrupt[${corrupt}]\n"
[error] ^
[error] 10 errors found
[error] (Compile / compileIncremental) Compilation failed
EDIT TO UPDATE:
After looking at the Chisel3 source, I added
import chisel3.{Printable, PrintableHelper}
and now I get a new error which looks more like I am just messing up my string:
[error] (run-main-0) java.lang.IllegalArgumentException: requirement failed
[error] java.lang.IllegalArgumentException: requirement failed
[error] at scala.Predef$.require(Predef.scala:268)
[error] at chisel3.printf$.escaped$1(Printf.scala:28)
[error] at chisel3.printf$.$anonfun$format$3(Printf.scala:32)
[error] ocketchiat chisel3.printf$.$anonfun$format$3$adapted(Printf.scala:32)
[error] at scala.collection.TraversableLike.$anonfun$map$1(TraversableLike.scala:238)
[error] at scala.collection.IndexedSeqOptimized.foreach(IndexedSeqOptimized.scala:36)
[error] at scala.collection.IndexedSeqOptimized.foreach$(IndexedSeqOptimized.scala:33)
[error] at scala.collection.immutable.StringOps.foreach(StringOps.scala:33)
[error] at scala.collection.TraversableLike.map(TraversableLike.scala:238)
[error] at scala.collection.TraversableLike.map$(TraversableLike.scala:231)
[error] at scala.collection.immutable.StringOps.map(StringOps.scala:33)
[error] at chisel3.printf$.format(Printf.scala:32)
[error] at chisel3.internal.firrtl.Emitter.emit(Emitter.scala:75)
[error] at chisel3.internal.firrtl.Emitter.$anonfun$moduleDefn$4(Emitter.scala:140)
EDIT TO UPDATE:
I added more verbosity to the requires in the printf code and I think it doesn't like tabs (\t):
[error] (run-main-0) java.lang.IllegalArgumentException: requirement failed: char to Int 9 must be >= 32
[error] java.lang.IllegalArgumentException: requirement failed: char to Int 9 must be >= 32
EDIT TO UPDATE:
I modified chisel3 to be OK with tabs, and now the code compiles and runs, but this is one of the resulting verilog strings which is obviously not right. I tried the string2Printable import you suggested but still get the following:
freechips.rocketchip.system.DefaultConfig.v: $fwrite(32'h80000002,"PLIC_TL_IFC A:\tPrintables(ArrayBuffer(PString(opcode[), Decimal(UInt<3>(IO in unelaborated TLMonitor)), PString(]\t)))Printables(ArrayBuffer(PString(param[), Decimal(UInt<3>(IO in unelaborated TLMonitor)), PString(]\t)))Printables(ArrayBuffer(PString(size[), Decimal(UInt<2>(IO in unelaborated TLMonitor)), PString(]\t)))Printables(ArrayBuffer(PString(source[), Decimal(UInt<9>(IO in unelaborated TLMonitor)), PString(]\t)))Printables(ArrayBuffer(PString(address[), Decimal(UInt<28>(IO in unelaborated TLMonitor)), PString(]\t)))Printables(ArrayBuffer(PString(user[), PString(None), PString(]\t)))Printables(ArrayBuffer(PString(mask[), Decimal(UInt<8>(IO in unelaborated TLMonitor)), PString(]\t)))Printables(ArrayBuffer(PString(data[), Decimal(UInt<64>(IO in unelaborated TLMonitor)), PString(]\t)))Printables(ArrayBuffer(PString(corrupt[), Decimal(Bool(IO in unelaborated TLMonitor)), PString(]\n)))"); // #[Monitor.scala 577:40:freechips.rocketchip.system.DefaultConfig.fir#64082.10]
freechips.rocketchip.system.DefaultConfig.v: $fwrite(32'h80000002,"PLIC_TL_IFC TLBundleD(opcode -> %d, param -> %d, size -> %d, source -> %d, sink -> %d, denied -> %d, data -> %d, corrupt -> %d)",io_in_d_bits_opcode,2'h0,io_in_d_bits_size,io_in_d_bits_source,1'h0,1'h0,io_in_d_bits_data,1'h0); // #[Monitor.scala 578:40:freechips.rocketchip.system.DefaultConfig.fir#64090.10]
For reference, here is the callsite where I am actually calling this:
when (bundle.a.fire()) { printf(p"$prefix ${bundle.a.bits}")}
when (bundle.d.fire()) { printf(p"$prefix ${bundle.d.bits}")}
Note the bundle.d.bits looks "okay" because I haven't given it a specific toPrintable function, but bundle.a.bits is a mess.
EDIT: RESOLVED
The problem is I had changed my toPrintable in the course of debugging to be of the form
override def toPrintable: Printable = {
"A:\t" +
p"opcode[$opcode]\t" +
...
p"corrupt[$corrupt]\n"
}
}
The first un-p string was making the rest of them just be normal strings, ignoring the p. I put the first p"A:\t" back and now it interpolates correctly.

Answer 1

The import chisel3._ should be enough. Try looking at the examples in the Chisel3 repo such as LFSR16.scala. If that doesn't help can you show the error message.