Information is needed to write backend functionality for Intel handhelds. The following commands should provide the data to make backend calls for testing
sudo dmesg | grep locked if anything doesn't work may show if RAPL is locked by BIOS
cat /sys/devices/virtual/powercap/intel-rapl/intel-rapl:0/enabled is RAPL config enabled?
echo 1 | sudo tee /sys/devices/virtual/powercap/intel-rapl/intel-rapl:0/enabled can it be enabled?
Name/function of each constraint:
cat /sys/devices/virtual/powercap/intel-rapl/intel-rapl:0/constraint_0_namecat /sys/devices/virtual/powercap/intel-rapl/intel-rapl:0/constraint_1_namecat /sys/devices/virtual/powercap/intel-rapl/intel-rapl:0/constraint_2_name
Can we edit the contsraints?
echo "8000000" | sudo tee /sys/class/powercap/intel-rapl/intel-rapl:0/constraint_0_power_limit_uw set to 8W
if there is anything in /sys/devices/virtual/powercap/intel-rapl related to MMIO, newer chips use that and it might be a little different.
if it does it probably has both. its not well documented though so experimenting will be needed.
ruineka
commented
2 years ago 
Information is needed to write backend functionality for Intel handhelds. The following commands should provide the data to make backend calls for testing
sudo dmesg | grep lockedif anything doesn't work may show if RAPL is locked by BIOScat /sys/devices/virtual/powercap/intel-rapl/intel-rapl:0/enabledis RAPL config enabled?echo 1 | sudo tee /sys/devices/virtual/powercap/intel-rapl/intel-rapl:0/enabledcan it be enabled?Name/function of each constraint:
cat /sys/devices/virtual/powercap/intel-rapl/intel-rapl:0/constraint_0_namecat /sys/devices/virtual/powercap/intel-rapl/intel-rapl:0/constraint_1_namecat /sys/devices/virtual/powercap/intel-rapl/intel-rapl:0/constraint_2_nameDefault values:
cat /sys/class/powercap/intel-rapl/intel-rapl:0/constraint_0_power_limit_uwcat /sys/class/powercap/intel-rapl/intel-rapl:0/constraint_1_power_limit_uwcat /sys/class/powercap/intel-rapl/intel-rapl:0/constraint_2_power_limit_uwCan we edit the contsraints?
echo "8000000" | sudo tee /sys/class/powercap/intel-rapl/intel-rapl:0/constraint_0_power_limit_uwset to 8Wif there is anything in
/sys/devices/virtual/powercap/intel-raplrelated to MMIO, newer chips use that and it might be a little different. if it does it probably has both. its not well documented though so experimenting will be needed.