open-source-silicon.dev

Yay! I wrote it!
<https://vlsi.jp/OpenMPWSRAM_eng.html#using-sram-with-openmpw>

In my first few MPWs with this, I didn't set these PDN hooks. Did something change that requires them?

We are working on better documentation for OpenRAM. Do you want to contribute this? (Please?)

Looking closer, why is your dout delayed several cycles? It should come out the same cycle in the second half of the cycle.

Ohh, it is because your clock frequency is so fast...

Thanks for the call, ~I just tried the PDN hook thing and didn't need to set it. I'll update the post soon! Thank you!~

There is not much I can do about the documentation, but I would be happy to help.

Screenshot from 2022-10-11 15-15-33.png

Sorry, I commented out FP_PDN_MACRO_HOOKS and got an LVS error. I guess I still need to investigate.

Screenshot from 2022-10-11 15-24-56.png

I solved the dout problem by changing the clock period, as you suggested! Thank you!

Screenshot from 2022-10-11 15-45-44.png

<@U02BMCBFRK3> `FP_PDN_MACRO_HOOKS` must, otherwise macro won't get powered and throw LVS error for the same

Is `GRT_OBS` still necessary for SRAM now? I am not sure because I haven't successfully harden with SRAM yet, but <https://github.com/The-OpenROAD-Project/OpenLane/issues/1354|vijayank88 suggested me to do so>. And I found so many people add `GRT_OBS`.

Wow, I turned on DRC and got an error. What the heck.
Perhaps `GRT_OBS` is needed. I will look into this now.

Screenshot from 2022-10-11 16-58-42.png

In my case, it may be insufficient memory.
I will increase the swap area and try again.

Screenshot from 2022-10-11 17-52-31.png

<@U0430SMHTPS>
This project sounds like it could use SRAM.
<https://github.com/semify-eda/caravel_wfg/blob/wfg-mpw-7/openlane/user_project_wrapper/config.tcl#L60>
<https://platform.efabless.com/projects/1202>

<@U0430SMHTPS>
```set ::env(MAGIC_DRC_USE_GDS) 0
set ::env(RUN_MAGIC_DRC) 0
set ::env(QUIT_ON_MAGIC_DRC) 0```
Now I've avoided the DRC error and the precheck passes.

ok, so it is not necessary for pre-build SRAM macro now.

<@U0430SMHTPS>
So `GRT_OBS` is probably not necessary to use SRAM.