Power Planning Script Confusion

[garfield118]

I have attached a snapshot of a macro at floorplan stage of riscV32i. I can see that the macros have Metal 4 power stripes on them but the power planning of the given openroad script do not seem to have any power stripes connecting them. Is there anyway I can check if the macros have not gotten any power stripes connecting them?

[vijayank88]

@gadfort fyi

[vijayank88]

Refer https://github.com/The-OpenROAD-Project/OpenROAD/tree/master/src/pdn#define-a-macro-power-grid and pdn.tcl updated for the same.
@garfield118 did you checked final layout file?

[vijayank88]

@maliberty
Can you please confirm, the pdn.tcl need to be updated?

[garfield118]

Refer https://github.com/The-OpenROAD-Project/OpenROAD/tree/master/src/pdn#define-a-macro-power-grid and pdn.tcl updated for the same. @garfield118 did you checked final layout file?

This is the postroute odb. There are signal,clk and ground connection to them. But still the macros power connections stripes seems still missing to me(All the metal 4 stripes on the macro are not connected to any power stripes).

[vijayank88]

@garfield118
How you resolved the issue?

[garfield118]

@garfield118 How you resolved the issue?

define_pdn_grid -name {core_macro} -voltage_domains {CORE} -macro -orient {R0 R180 MX MY} -halo {2.0 2.0 2.0 2.0} -default grid_over_boundary
add_pdn_connect -grid {core_macro} -layers {M4 M5}

Yes, add this script to the /openRoad/pdn/grid_strategy-M2-M5-M7.tcl file. And the via's will be generated.

[maliberty]

I would need a test case to see what is wrong. It isn't obvious from just the description here.

[vijayank88]

@maliberty
For nangate45 and sky130 in pdn.tcl macro_grid available to create power grid for macros.

In ASAP7 only standard cell grid available and not defined any macro_grid. check this grid_strategy.

Is that need to be fixed or not?

[maliberty]

We didn't have any memories for asap7 so there was no need. Feel free to create one if needed.

[vijayank88]

I am just referring this nangate45 macro grid.
https://github.com/The-OpenROAD-Project/OpenROAD-flow-scripts/blob/master/flow/platforms/nangate45/grid_strategy-M1-M4-M7.tcl

For asap7
How to choose width, pitch and offset?
I have used M4 M5 for macro grid connection.

[vijayank88]

I made similar macro grid for ASAP7.

####################################
# grid for: CORE_macro_grid_1
####################################
define_pdn_grid -name {CORE_macro_grid_1} -voltage_domains {CORE} -macro -orient {R0 R180 MX MY} -halo {2.0 2.0 2.0 2.0} -cells {.*}
add_pdn_connect -grid {CORE_macro_grid_1} -layers {M4 M5}
####################################
# grid for: CORE_macro_grid_2
####################################
define_pdn_grid -name {CORE_macro_grid_2} -voltage_domains {CORE} -macro -orient {R90 R270 MXR90 MYR90} -halo {2.0 2.0 2.0 2.0} -cells {.*}
add_pdn_connect -grid {CORE_macro_grid_2} -layers {M4 M6}

But I don't find any connection with above update.

asap7/riscv32i has memories now.