chipsalliance
Error from instantiating MMCME2_BASE primitive
I have been testing the symbiflow toolchain on a few designs and have run into an error while trying to run the pong design on project_f. When I try to run the design I get this error from the tool chain:
Message: Failed to find matching architecture model for 'MMCME2_BASE'
From what I can tell this is coming from file clock_gen_480p.sv trying to instance the MMCME primitive. Does symbiflow offer support for this yet?
@WhiteNinjaZ At the moment there is a PR which is soon-to-be-merged and open to add support for the MMCM primitives in symbiflow-arch-defs. For context, symbiflow-arch-defs is the repository that generates the device data used to place&route.
Once that PR is merged and new device data generated by CI, we will be able to use MMCM primitives. In the meantime, unless strictly necessary, you might use PLLE2_BASE or PLLE2_ADV primitives instead.
@acomodi Per chance do you know the time frame for when the MMCME2_BASE support in symbiflow-arch-defs will be done?
@WhiteNinjaZ Hello. I can't tell about the time frame of doing that but adding MMCME2_BASE is a matter of writing a Yosys techmap in the same way as it is done for PLLE2_BASE. I'd prefer to do that after landing the MMCM PR but if you are lively interested in having the techmap there I can add it.
On the other hand merging https://github.com/SymbiFlow/symbiflow-arch-defs/pull/1729 is more complicated as there is a CI failure not directly related to PLL/MMCM support which require further investigation.
