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.

• [1] https://www.raspberrypi.com/documentation/computers/os.html#rpi-update
• [2] https://www.raspberrypi.com/documentation/computers/raspberry-pi.html#raspberry-pi-4-boot-eeprom
• [3] https://www.raspberrypi.com/documentation/computers/config_txt.html#overclocking-options

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

License

MIT

Author Information

I'm Gaëtan Trellu (goldyfruit), let's discuss :) - 2021