measure power

[btwbtw01]

Hi,
Can I measure the power or energy only DRAM and PL side? Our application is to compress activation to reduce DRAM access power. Does Xilinx have the tool to support? Maybe Xilinx Power Estimator?

Has anybody ever used the tool to measure power and energy that comes from Xilinx?

Thanks!!

[fpjentzsch]

Hi, which board are you targeting? For some development boards (e.g. ZCU102) you can measure power consumption of various rails by reading out some board components via the I2C/PMBUS:

1. The power controller chips: Works even with an external device ("MAXPOWERTOOL") you connect to the PMBUS header, but is horribly inaccurate for the ZCU102 due to a board design issue.
2. The power monitor chips: Fairly accurate, can be set-up and polled via PS (software), PL, or the system controller if your board has one.

I can't help you with power estimation during design time, but I'd also like to know how accurate this can get.

[fpjentzsch]

I believe the official guide to build PYNQ images (https://pynq.readthedocs.io/en/latest/pynq_sd_card.html) worked for me in the past.

Yes, you will need to simulate the design in Vivado with realistic input data. Then you can save switching activity information to a file. However, you can't do that right out-of-the-box with FINN because we do RTL simulation outside of Vivado with Verilator.

[218w1d7706]

hi, @fpjentzsch
is it good to use SCUI for power monitoring or i have to use use power advantage tool?
thank you.

[Ba1tu3han]

@fpjentzsch

Hello Felix,

Similarly I want to measure total power consumption of my HW design which is a CNV-like model in Vivado. I completed succesfully all steps of FINN and implemented in PYNQ-Z2 (does not have PMBUS).

The power analysis does not make sense and it has low confidence level.

What do you recommend to measure total power to compare different bit-width variation of the same NN model?

Bests,

[fpjentzsch]

Hi, you could measure the total board power going into the PYNQ-Z2 and see if you can detect meaningful differences between the models while they are running continuously. I prefer to use the onboard current measurement infrastructure (via I2C/PMBUS), but small boards like the Z2 often lack this feature.

I have also heard of people soldering their own shunt resistors onto PYNQ boards to measure the main power rail with an external meter...

[Ba1tu3han]

Hi Felix,

Thank you for your recommendation.

I am able to calculate the theoretical power consumption on Vivado by using the Vivado Project file which is generated by FINN. It gives an general idea.

I will consider using a shunt resistor.

Bests,