PrimeTime Warnings ("check_power" command)

[Hanul]

Hello,

How can I fix those warnings below?

==========================================
pt_shell> check_power
Information: Checking 'out_of_table_range'.
Warning: There are 8395 out_of_range ramps.
Warning: There are 75 out_of_range loads.
Information: Checking 'missing_table'.
Information: Checking 'missing_function'.
0
==========================================

I can't find any solution for these warnings.

Thank you in advance.

 

[rca]

The warning just indicates you have some 8395 signal which have a transition value out side the table, you should have some transition violation. Then the power estimation could not calculate the power for this value which are outside the table provided by the liberty file.
Same stuff for cap violations.

 

[Hanul]

Thank you for your reply.

I'd like to know why it happened. Also, what should I do next to fix this?

Can you recommend me any reference for this?

 

[rca]

You need first to fix all violations.

 

[Hanul]

Re: PrimeTime Warnings ("check_power" command)

Yes, I wanna fix those violations.

Could you tell me the way to fix those?

- - - Updated - - -

Yes, I wanna fix those violations.

Could you tell me the way to fix those?

 

[rca]

during the PnR steps.

 

[Hanul]

Sorry but I can't understand what you meant.

I tried to calculate power just after synthesis and gate-level simulation. I've not done PnR yet.
(I synthesized my design in Topographical Mode though.)

This is my first time for gate-level simulation and PrimeTime power cacluation.
Could you advise me in more detail please?

Thank you a lot!

 

[Hanul]

To figure out this problem, I've designed another simple DFF module.
The detailed information is as follows.

However, I still cannot find where this problem came from and how to fix this.
Please help me out.

=============================================================================================

ramp 0.00 at pin 'D' of cell 'ff_reg_reg[1]' is out of ramp range (0.02, 1.02) of lib_cell 'DFFARX1'
ramp 0.00 at pin 'CLK' of cell 'ff_reg_reg[1]' is out of ramp range (0.02, 1.02) of lib_cell 'DFFARX1'
ramp 0.00 at pin 'RSTB' of cell 'ff_reg_reg[1]' is out of ramp range (0.02, 1.02) of lib_cell 'DFFARX1'
ramp 0.00 at pin 'D' of cell 'ff_reg_reg[0]' is out of ramp range (0.02, 1.02) of lib_cell 'DFFARX1'
ramp 0.00 at pin 'CLK' of cell 'ff_reg_reg[0]' is out of ramp range (0.02, 1.02) of lib_cell 'DFFARX1'
ramp 0.00 at pin 'RSTB' of cell 'ff_reg_reg[0]' is out of ramp range (0.02, 1.02) of lib_cell 'DFFARX1'
Warning: There are 6 out_of_range ramps.

=============================================================================================

 

[rca]

ok so if you want to estimate the power consumption after synthesis, you should ignore this warning, but the accuracy is "limited".
You could compare different run improvement.