moved raspberry specific settings to raspberrypi role

roles/raspberrypi/tasks/main.yml

@@ -0,0 +1,48 @@
+---
+- name: Test for raspberry pi /proc/cpuinfo
+  command: grep -E "Raspberry Pi|BCM2708|BCM2709|BCM2835|BCM2836" /proc/cpuinfo
+  register: grep_cpuinfo_raspberrypi
+  failed_when: false
+  changed_when: false
+
+- name: Test for raspberry pi /proc/device-tree/model
+  command: grep -E "Raspberry Pi" /proc/device-tree/model
+  register: grep_device_tree_model_raspberrypi
+  failed_when: false
+  changed_when: false
+
+- name: Set raspberry_pi fact to true
+  set_fact:
+    raspberry_pi: true
+  when:
+    grep_cpuinfo_raspberrypi.rc == 0 or grep_device_tree_model_raspberrypi.rc == 0
+
+- name: Set detected_distribution to Raspbian
+  set_fact:
+    detected_distribution: Raspbian
+  when:
+   - raspberry_pi|default(false)
+   - ansible_facts.lsb.id|default("") == "Raspbian" or ansible_facts.lsb.description|default("") is match("[Rr]aspbian.*")
+
+- name: Set detected_distribution to Raspbian (ARM64 on Debian Buster)
+  set_fact:
+    detected_distribution: Raspbian
+  when:
+    - ansible_facts.architecture is search("aarch64")
+    - raspberry_pi|default(false)
+    - ansible_facts.lsb.description|default("") is match("Debian.*buster")
+
+- name: Set detected_distribution_major_version
+  set_fact:
+    detected_distribution_major_version: "{{ ansible_facts.lsb.major_release }}"
+  when:
+    - detected_distribution | default("") == "Raspbian"
+
+- name: execute OS related tasks on the Raspberry Pi
+  include_tasks: "{{ item }}"
+  with_first_found:
+    - "prereq/{{ detected_distribution }}-{{ detected_distribution_major_version }}.yml"
+    - "prereq/{{ detected_distribution }}.yml"
+    - "prereq/{{ ansible_distribution }}-{{ ansible_distribution_major_version }}.yml"
+    - "prereq/{{ ansible_distribution }}.yml"
+    - "prereq/default.yml"

roles/raspberrypi/tasks/prereq/Raspbian.yml

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+---
+- name: Activating cgroup support
+  lineinfile:
+    path: /boot/cmdline.txt
+    regexp: '^((?!.*\bcgroup_enable=cpuset cgroup_memory=1 cgroup_enable=memory\b).*)$'
+    line: '\1 cgroup_enable=cpuset cgroup_memory=1 cgroup_enable=memory'
+    backrefs: true
+  notify: reboot
+
+- name: Flush iptables before changing to iptables-legacy
+  iptables:
+    flush: true
+  changed_when: false   # iptables flush always returns changed
+
+- name: Changing to iptables-legacy
+  alternatives:
+    path: /usr/sbin/iptables-legacy
+    name: iptables
+  register: ip4_legacy
+
+- name: Changing to ip6tables-legacy
+  alternatives:
+    path: /usr/sbin/ip6tables-legacy
+    name: ip6tables
+  register: ip6_legacy

roles/raspberrypi/tasks/prereq/Ubuntu.yml

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+---
+- name: Enable cgroup via boot commandline if not already enabled for Ubuntu on ARM
+  lineinfile:
+    path: /boot/firmware/cmdline.txt
+    backrefs: yes
+    regexp: '^((?!.*\bcgroup_enable=cpuset cgroup_memory=1 cgroup_enable=memory\b).*)$'
+    line: '\1 cgroup_enable=cpuset cgroup_memory=1 cgroup_enable=memory'
+  when:
+    - ansible_distribution == 'Ubuntu'
+    - ( ansible_facts.architecture is search("arm") or
+        ansible_facts.architecture is search("aarch64") )
+
+- name: Reboot to enable cgroups for Ubuntu on ARM
+  reboot:
+  when:
+    - ansible_distribution == 'Ubuntu'
+    - ( ansible_facts.architecture is search("arm") or
+        ansible_facts.architecture is search("aarch64") )

roles/raspberrypi/tasks/prereq/default.yml

@@ -0,0 +1 @@
+---