flow: scripts: final_report: analyze_power_grid runs only on one corner

[dnltz]

Description

When multiple corners are enabled for design, the final report script analyzes the power grid only once. Since no corner is defined, it automatically selects the fastest corner.

[INFO RCX-0443] 39090 nets finished
[INFO PSM-0040] All shapes on net VDD are connected.
########## IR report #################
Net              : VDD
Corner           : fast
Total power      : 2.93e-02 W
Supply voltage   : 1.35e+00 V
Worstcase voltage: 1.33e+00 V
Average voltage  : 1.35e+00 V
Average IR drop  : 1.61e-04 V
Worstcase IR drop: 1.92e-02 V
Percentage drop  : 1.42 %
######################################
[INFO PSM-0040] All shapes on net VSS are connected.
########## IR report #################
Net              : VSS
Corner           : fast
Total power      : 2.93e-02 W
Supply voltage   : 0.00e+00 V
Worstcase voltage: 7.46e-03 V
Average voltage  : 9.53e-05 V
Average IR drop  : 9.53e-05 V
Worstcase IR drop: 7.46e-03 V
Percentage drop  : 0.62 %
######################################

This is the loop to generate those reports.

    dict for {pwrNetName pwrNetVoltage} $::env(PWR_NETS_VOLTAGES) {
      set_pdnsim_net_voltage -net ${pwrNetName} -voltage ${pwrNetVoltage}
      analyze_power_grid -net ${pwrNetName} \
        -error_file $::env(REPORTS_DIR)/${pwrNetName}.rpt
    }

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I did some tests and it looks like the percentage drop is almost identical for the slow and fast corner. However, should we analyze all available corners by default instead of only one?

I don't know if this intentionally or got forgotten to implement in the past.

Suggested Solution

No response

Additional Context

No response

[maliberty]

I doubt it is intentional that we just do the one corner though it is somewhat faster. Fast corner seems to most likely to have an issue. I have no strong preference and would be ok with a PR to loop over all corners.

[dnltz]

Alright. I will take a look. If it requires too man reworks, we just stick to checking only one corner.