Thanks for opening this PR!
I believe @hngenc will have a deeper look at the uarch tomorrow, but I have a few high level questions to start with:

• Is the TilerController in come as an addition to the main controller, or as a replacement?
• The most recent version of Gemmini support transposing a matrix before the GEMM. I'm assuming the Tiler does not support that right now?
• I would have expected to see some changes in Configs.scala for a parameter that enables/disables the Tiler frontend elaboration. Am I missing something?
• I'm wondering whether the CISC naming is the best name to go with here (as opposed to HWTiler or something like that). My concern is that CISC tend to generate an automatic reaction from people (whether Pro or Anti, but still, an automatic reaction). Any thoughts?

Thanks for opening this PR!
I believe @hngenc will have a deeper look at the uarch tomorrow, but I have a few high level questions to start with:

• Is the TilerController in come as an addition to the main controller, or as a replacement?

its a submodule that sits parallel to the existing LoopUnroller+ROB frontend. it could be renamed "TilerFrontend"

• The most recent version of Gemmini support transposing a matrix before the GEMM. I'm assuming the Tiler does not support that right now?

transposing input matrices is not supported by the hardware tiler. that sounds like it would be a bit of work.

• I would have expected to see some changes in Configs.scala for a parameter that enables/disables the Tiler frontend elaboration. Am I missing something?

sure you could add that, but i'm guessing the saved area will be fairly small

• I'm wondering whether the CISC naming is the best name to go with here (as opposed to HWTiler or something like that). My concern is that CISC tend to generate an automatic reaction from people (whether Pro or Anti, but still, an automatic reaction). Any thoughts?

i dont care about the external branding of this addition. HWTiler is fine with me. the code has "cisc" 32 times, but can easily be sed'ed with "tiler" if desired

The code LGTM. There's actually one last thing that I forgot to ask about before: Could you add a section to the README.md describing the format of the CISC instructions (somewhere underneath the ISA section perhaps)?

Was this tested on FireSim with the various ResNet/MobileNet tests?

Was this tested on FireSim with the various ResNet/MobileNet tests?

the original, unmerged Tiler code was tested on FireSim for ResNet/MobileNet. However, FireSim was not run on the merged code in this PR.

The code LGTM. There's actually one last thing that I forgot to ask about before: Could you add a section to the README.md describing the format of the CISC instructions (somewhere underneath the ISA section perhaps)?

done

We apparently pass on FireSim, so this looks good to merge.