How can I control power limit of CPU/GPU ?

Robotics & Edge Computing Jetson & Embedded Systems Jetson TX2
1

Hi,
I want to control power limit of System input, CPU and GPU. As possible, I don’t want to use tool.

I found some files :
‘~~/0-0041/iio:device1/power/crit_power_limit_1’
then, and revised the file value. For example, ‘crit_power_limit_1’ values to 8000 expecting it limits CPU power as 8000mw
But in doesn’t work.

2

Hi, please refer to this doc: [url]https://developer.nvidia.com/embedded/dlc/jetson-tx1-tx2-voltage-current-config[/url]

3

Thanks Trumany,

I read the doc. The document says that configure below file
hardware/nvidia/platform/t18x/common/kernel-dts/t18x-commonplatforms/tegra186-quill-p3310-1000-a00-powermon.dtsi
Where is ‘hardware’? Do I need to install jetpack?

4

Please refer to below to get the source.

[url]https://docs.nvidia.com/jetson/archives/l4t-archived/l4t-282/index.html#page/Tegra%2520Linux%2520Driver%2520Package%2520Development%2520Guide%2Fkernel_custom.html%23wwpID0E0SD0HA[/url]

or

[url]https://docs.nvidia.com/jetson/archives/l4t-archived/l4t-282/index.html#page/Tegra%2520Linux%2520Driver%2520Package%2520Development%2520Guide%2Fkernel_custom.html%23wwpID0E0HD0HA[/url]

5

You can also get the source via the “source_sync.sh” script with each driver package (and if you’ve flashed via JetPack, then the driver package is already there). You would need to know which L4T release though. Find the output of this on the Jetson:

head -n 1 /etc/nv_tegra_release

Assuming it is R28.2.1, then it would go something like this for kernel source (which has the hardware subdirectory):

./source_sync.sh -k tegra-l4t-r28.2.1
6

Thanks, vickyy, linuxdev !!
I found some power profile files
In this document ‘https://developer.nvidia.com/embedded/dlc/jetson-tx1-tx2-voltage-current-config’,
‘tegra186-quill-p3310-1000-a00-powermon.dtsi’ file is a key to control power limit of tx2 but there is no information about power, voltage or current limit.

  1. So, Which file do I need to edit?
  2. Also, if I edit some files, do I need to rebuild kernel?
7

Actually, I want to measure a performance of some tasks changing power budget(limit) of supply, CPU, GPU with own DVFS system, if possible, dynamically changing the power limit durint a task.