AMD GPU power cap

gpu_power_cap.sh

#!/bin/bash

# Note: make sure the card / hwmon indexes correspond to your GPU!
# They can differ depending on your set up.

gpu_hwmon="/sys/class/drm/card0/device/hwmon/hwmon2"

# Takes cap parameter in Watts. "max" sets it to max allowed.
cap_watts=$1

# Internal caps values are in microwatts
min_cap=$(cat "${gpu_hwmon}/power1_cap_min")
max_cap=$(cat "${gpu_hwmon}/power1_cap_max")
cur_cap=$(cat "${gpu_hwmon}/power1_cap")

function show_caps() {
  echo "Current GPU power cap: ${cur_cap} ($((cur_cap / 1000000)) Watts)."
  echo "Maximum GPU power cap: ${max_cap} ($((max_cap / 1000000)) Watts)."
  echo "Minimum GPU power cap: ${min_cap} ($((min_cap / 1000000)) Watts)."
}

if (($# == 0)); then
   show_caps
   exit 0
fi

if [[ "$cap_watts" == "max" ]]; then
  cap_microwatts=$max_cap
else
  cap_microwatts="${cap_watts}000000"
fi

num_regex='^[0-9]+$'
if (($# > 1)) || ! [[ "$cap_microwatts" =~ $num_regex ]] || (( ($cap_microwatts < $min_cap) || ($cap_microwatts > $max_cap) )); then
   echo "Invalid parameters! Set numeric cap between $((min_cap / 1000000)) and $((max_cap / 1000000)) Watts."
   exit 1
fi

echo $cap_microwatts | sudo tee "${gpu_hwmon}/power1_cap" > /dev/null
cur_cap=$(cat "${gpu_hwmon}/power1_cap")
show_caps