open-source-silicon.dev

<https://github.com/The-OpenROAD-Project/OpenLane/issues/1667|#1667 gds streaming should handle macro with different units>
Issue created by <https://github.com/proppy|proppy>
*Description*

It seems that final gds streaming always assume that macros `UNITS` are the same as the main gds ones (`0.001`) resulting in the macro being scaled down during the final merge.

See the following example with `UNITS 0.005 5e-09` of a macro being merged in a bigger layout:  
<https://user-images.githubusercontent.com/5268/220827546-aaa75131-7ce5-470b-b32e-985076d13455.png|image>  
effectively resulting in the merged polygons being 5 times smaller.

*Expected Behavior*

Appropriate scaling is applied on the polygon from the gds before merging them.

Re-importing the macro in a new layout in klayout with a database unit of `0.001` does allow to workaround this issue.

*Environment report*

```
openlane                  2023.02.19_0_g95580b00 20230222_073528    litex-hub
open_pdks.gf180mcuc       1.0.393_0_ge6f9c88 20230222_150152    file:///tmp/conda-bld
openroad                  2.0_6924_g037e4e3a4 20230222_073528    litex-hub
klayout                   0.28.5_30_ga04f2940a 20230222_073528_py37    litex-hub
```

*Reproduction material*

attached the resulting gds for the layout and the original macro (with a different database units).

<https://github.com/The-OpenROAD-Project/OpenLane/files/10810561/merge-layout-macro.zip|merge-layout-macro.zip>

*Relevant log output*

```
[STEP 29]
[INFO]: Streaming out GDSII with KLayout (log: digital/runs/RUN_2023.02.23_14.04.05/logs/signoff/29-gdsii-klayout.log)...
Warning: No mapping for layer 'Metal1', purpose 'LEFPIN' - layer is ignored
Warning: No mapping for layer 'Metal1', purpose 'LEFLABEL' - layer is ignored
Warning: No mapping for layer 'Nwell', purpose 'LEFPIN' - layer is ignored
Warning: No mapping for layer 'Nwell', purpose 'LEFLABEL' - layer is ignored
Warning: No mapping for layer 'Pwell', purpose 'LEFPIN' - layer is ignored
Warning: No mapping for layer 'Pwell', purpose 'LEFLABEL' - layer is ignored
Warning: No mapping for layer 'Metal1', purpose 'LEFOBS' - layer is ignored
Warning: No mapping for layer 'Metal2', purpose 'LEFOBS' - layer is ignored
Warning: No mapping for layer 'Metal3', purpose 'LEFOBS' - layer is ignored
Warning: No mapping for layer 'Metal4', purpose 'LEFOBS' - layer is ignored
Warning: No mapping for layer 'Metal5', purpose 'LEFOBS' - layer is ignored
[INFO] Clearing cells...
[INFO] Merging GDS files...
	/home/proppy/silicon-gf180mcuC-env/share/pdk/gf180mcuC/libs.ref/gf180mcu_fd_sc_mcu7t5v0/gds/gf180mcu_fd_sc_mcu7t5v0.gds
	/home/proppy/src/github.com/spnadig/GF180_GAFE_1/digital/../TopLevel_oscillator.gds
	/home/proppy/src/github.com/spnadig/GF180_GAFE_1/digital/../OTA_2stage.gds
[INFO] Copying top level cell 'top'...
[INFO] Checking for missing GDS...
[INFO] All LEF cells have matching GDS cells.
[INFO] Writing out GDS '/home/proppy/src/github.com/spnadig/GF180_GAFE_1/digital/runs/RUN_2023.02.23_14.04.05/results/signoff/top.klayout.gds'...
[INFO] Done.
```
<https://github.com/The-OpenROAD-Project/OpenLane|The-OpenROAD-Project/OpenLane>