Need some advice for power routing a macro in my design. As it stands hardening the user design fails on LVS, with a mismatch due to disconnected power and ground nets. After playing with it, by disabling the LVS check, and wrapping the design in User_Project_Wrapper appears to solve the power routing issue. Is this appropriate or am i jerry rigging my design this way?

@Liam Oswald Are your macro power names the same as the top level power names? If not, does your config.json file contain an

FP_PDN_MACRO_HOOKS

variable to specify the connections? Disabling the LVS check does not “solve” the problem, but rather allows openlane to complete with unconnected power to the macro. Some people use this and do manual power routing afterward.

@Mitch Bailey We have a member of the team working on manual connections at the moment, but if possible i would like automatic routing, because right now we are dealing with a small demo macro, the full macro will take some time to connect. The macro port names are identical across the GDS/Verilog (Using

vccd1 & vssd1

). The macro hooks appear to be applying properly. To add to the confusion, a colleague found earlier that by changing config.json to include

MAGIC_EXT_USE_GDS": true,

gets

vssd1

to route correctly, but

vccd1

is still floating. I'm currently playing around with various other settings to see if they have any effect, but I'm shooting in the dark.

There have been problems reported with small macros that are not big enough to intersect with the required power/ground power rails. Sometimes this can be solved by moving the macro. The only thing that

MAGIC_EXT_USE_GDS

will do is change from a maglef based extraction to a GDS based extraction. I don’t think it affects routing.