Resolve implicit-width-truncation warnings - #278
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firtool-1.154.0 and later warn on all implicit width truncations. These width truncations were flagged in stock Chipyard builds. For all width truncations, use the equivalent `Connectable` operator (`:<=` or `:<>=`), along with `.squeeze`/`.squeezeAll`. This has the same behavior as the original `:=`/`<>` connections, since those truncate when the producer in a connection is wider than the consumer. Note that in `TLSerdes.scala`, we needed the `wireProtocol` helper function. The Connectable operators require that the types being connected are structurally type-equivalent. When the five different TL bundles were placed in the `Seq`, their types were erased inside the iteration over `in_channels`. So we connect the `io.protocol` output to the appropriate TL bundle with `wireProtocol` before those types get erased.
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firtool-1.154.0 and later warn on all implicit width truncations (llvm/circt#10621). These width truncations were flagged in stock Chipyard builds.
For all width truncations, use the equivalent
Connectableoperator (:<=or:<>=), along with.squeeze/.squeezeAll. This has the same behavior as the original:=/<>connections, since those truncate when the producer in a connection is wider than the consumer.Note that in
TLSerdes.scala, we needed thewireProtocolhelper function. The Connectable operators require that the types being connected are structurally type-equivalent. When the five different TL bundles were placed in theSeq, their types were erased inside the iteration overin_channels. So we connect theio.protocoloutput to the appropriate TL bundle withwireProtocolbefore those types get erased.