# Fix T480 / T480s / X1C6 Throttling on Linux
Workaround for Linux throttling issues on Lenovo T480 / T480s / X1C6 notebooks as described [here](https://www.reddit.com/r/thinkpad/comments/870u0a/t480s_linux_throttling_bug/).

This script forces the CPU package power limit (PL1/2) to **44 W** (29 W on battery) and the temperature trip point to **97 'C** (85 'C on battery) by overriding default values in MSR and MCHBAR every 5 seconds (30 on battery) to block the Embedded Controller from resetting these values to default.

## Requirements
The python module `python-periphery` is used for accessing the MCHBAR register by memory mapped I/O. 

## Installation
```
git clone https://github.com/erpalma/lenovo-throttling-fix.git
sudo -H pip install python-periphery
sudo make install
sudo systemctl enable lenovo_fix.service
sudo systemctl start lenovo_fix.service
```

## Configuration
The script can be configured by editing `lenovo_fix.py` directly. There exist two profiles `AC` and `BATTERY`:
```
config = {
    'AC': {
        'UPDATE_RATE_SEC': 5,  # Update the registers every this many seconds
        'PL1_TDP_W': 44,  # Max package power for time window #1
        'PL1_DURATION_S': 28,  # Time window #1 duration
        'PL2_TDP_W': 44,  # Max package power for time window #2
        'PL2_DURATION_S': 0.002,  # Time window #2 duration
        'TRIP_TEMP_C': 97  # Max allowed temperature before throttling
    },
    'BATTERY': {
        'UPDATE_RATE_SEC': 30,  # Update the registers every this many seconds
        'PL1_TDP_W': 29,  # Max package power for time window #1
        'PL1_DURATION_S': 28,  # Time window #1 duration
        'PL2_TDP_W': 44,  # Max package power for time window #2
        'PL2_DURATION_S': 0.002,  # Time window #2 duration
        'TRIP_TEMP_C': 85  # Max allowed temperature before throttling
    },
}
```

## Disclaimer
This script overrides the default values set by Lenovo. I'm using it without any problem, but it is still experimental so use it at your own risk. This script can be probably adapter/used on other notebooks too.