prepi

Ansible Role: Prepi

This Ansible role will apply some configurations to obtain the best performances from a Raspberry Pi 4B board and later.

prepi stands for "Prepare Raspberry Pi".

First, a major, MAJOR caveat: You are responsible of the choices made with this role, you decide which firmware[1], which EEPROM[2] you want to use. The same rule applies to the overclocking[3] feature. Remember that overclocking requires a proper active cooling system.

That being said, this role performs the following tasks (depending your wishes):

Update Raspberry Pi OS to the latest version
Add Debian backports repository (customizable)
Update firmware using the next branch which provide kernel 5.10 and edge firmware (customizable)
Update EEPROM using the beta version which provide edge features (customizable)
Setup initial_turbo to speedup the boot process
Overclock the Raspberry Pi to 2Ghz (customizable)
Mount /tmp on a RAMDisk
Optimize / partition mount options to improve SDcard read/write
Manage I2C, SPI & UART interfaces (customizable)
Set CPU governor to performance to avoid context switching between the idle* kernel functions (customizable)
Install and configure PulseAudio (non-system wide) (customizable)
Reboot the Raspberry Pi when new firmware or EEPROM are installed (customizable)

This role has been developed on a Raspberry Pi 4B with Raspberry Pi OS 64-bit.

Please read the documentation links below before taking any decisions.

Requirements

Raspberry Pi 4B board and later
Raspberry Pi OS 64-bit (required for board with more than 4GB of RAM)

Role Variables

Available variables are listed below, along with default values (see defaults/main.yml):

---
# System user to add to system group such as gpio, audio, etc...
prepi_pi_user: pi

# Set the Raspberry Pi hostname
prepi_hostname: smartgic-pi4b8-13

# Set the CPU governor
#  - ondemand (less power consumption but less performances)
#  - performance (more power consumption but more performances)
prepi_cpu_governor: performance

# Use fast DNS nameservers (CloudFlare and Google)
# Keep in mind that if you are using a DHCP server these changes will be override
prepi_nameservers:
  - 1.1.1.1
  - 8.8.8.8

# Update the firmware
prepi_firmware_update: yes

# Which firmware branch to use
#  - master (stable)
#  - next (edge firmware and kernel)
prepi_firmware_branch: next

# Which EEPROM release to use
#  - critical (rarely updated)
#  - stable (updated when new/advanced features have been successfully beta tested)
#  - beta (new or experimental features are tested here first)
prepi_eeprom: beta

# Overclock CPU/GPU
prepi_overclock: yes

# Use with caution, this parameter allows to use an higher voltage
prepi_force_turbo: no

# CPU frequence to overclock
# If the Raspberry Pi is unstable try to reduce the clock
prepi_cpu_freq: 2000

# GPU frequence to overclock
prepi_gpu_freq: 650

# Voltage to use, the higher the CPU clock will be the higher the voltage should be
# 6 is the limit when prepi_force_turbo is set to no, higher voltage could damage your board
prepi_voltage: 6

# Enable I2C interface
prepi_i2c_enable: yes

# Enable SPI interface
prepi_spi_enable: yes

# Disable UART interface
prepi_uart_enable: no

# Install and configure PulseAudio
prepi_pulseaudio: yes

# PulseAudio persistent when user disconnect and start at boot time.
prepi_pulseaudio_daemon: yes

# Enable Debian backports repository to get the latest packages
prepi_backports_enable: yes

# Reboot the Raspberry Pi when new firmware or EEPROM are installed
prepi_reboot: yes

# Disable the onboarding screen configuration (when using the Raspberry Pi OS desktop version)
prepi_disable_onboarding_screen: yes

Dependencies

Same as for the requirements section.

Example Playbook

Inventory file with rpi group which has one host named rpi4b01 with the IP address 192.168.1.97.

[rpi]
rpi4b01 ansible_host=192.168.1.97 ansible_user=pi

Basic playbook running on rpi group using the pi user to connect via SSH (based on the inventory) with some custom variables.

---
- hosts: rpi
  gather_facts: no
  become: yes

  # Install Python using raw module to make sure requirements are installed
  pre_tasks:
    - name: Install Python 3.x Ansible requirement
      raw: apt-get install -y python3
      changed_when: no

- hosts: rpi
  become: yes

  vars:
    prepi_hostname: smartgic-pi4b8-13
    prepi_cpu_freq: 2000
    prepi_cpu_governor: performance
    prepi_force_turbo: yes

  tasks:
    - import_role:
        name: smartgic.prepi
      tags:
        - prepi
        - raspberry