From f42442dd0e89ff9d91429d9abd435d77937ad012 Mon Sep 17 00:00:00 2001
From: Jordan Holt <jordan@vimium.com>
Date: Sat, 3 Aug 2024 20:11:11 +0100
Subject: [PATCH] Add skycam host

---
 flake.nix                               |  1 +
 hosts/common.nix                        |  4 +-
 hosts/skycam/README.md                  | 22 ++++++++
 hosts/skycam/default.nix                | 71 +++++++++++++++++++++++++
 hosts/skycam/hardware-configuration.nix | 33 ++++++++++++
 5 files changed, 129 insertions(+), 2 deletions(-)
 create mode 100644 hosts/skycam/README.md
 create mode 100644 hosts/skycam/default.nix
 create mode 100644 hosts/skycam/hardware-configuration.nix

diff --git a/flake.nix b/flake.nix
index b9bdfc7..4a3ddef 100644
--- a/flake.nix
+++ b/flake.nix
@@ -104,6 +104,7 @@
         mail = mkNixosSystem { system = "x86_64-linux"; name = "mail"; };
         odyssey = mkNixosSystem { system = "x86_64-linux"; name = "odyssey"; };
         pi = mkNixosSystem { system = "aarch64-linux"; name = "pi"; extraModules = [ nixos-hardware.nixosModules.raspberry-pi-4 ]; };
+        skycam = mkNixosSystem { system = "aarch64-linux"; name = "skycam"; extraModules = [ nixos-hardware.nixosModules.raspberry-pi-4 ]; };
         vps1 = mkNixosSystem { system = "x86_64-linux"; name = "vps1"; };
       };
 
diff --git a/hosts/common.nix b/hosts/common.nix
index 85fb6e3..6fe3fe9 100644
--- a/hosts/common.nix
+++ b/hosts/common.nix
@@ -1,4 +1,4 @@
-{ config, lib, pkgs, ... }:
+{ config, pkgs, ... }:
 
 {
   time.timeZone = "Europe/London";
@@ -15,7 +15,7 @@
     LC_TELEPHONE = "en_GB.UTF-8";
     LC_TIME = "en_GB.UTF-8";
   };
-  
+
   console.keyMap = "uk";
 
   security.sudo.execWheelOnly = true;
diff --git a/hosts/skycam/README.md b/hosts/skycam/README.md
new file mode 100644
index 0000000..de64288
--- /dev/null
+++ b/hosts/skycam/README.md
@@ -0,0 +1,22 @@
+# Skycam
+
+## Overview
+Raspberry Pi 4-based webcam
+
+## Specs
+* SoC - Broadcom BCM2711
+* CPU - ARM Cortex-A72 @ 1.8 GHz
+* Memory - 8 GB LPDDR4
+
+### Disks
+Device | Partitions _(filesystem, usage)_
+--- | ---
+SD card | `/dev/mmcblk0` (ext4, NixOS Root)
+
+### Networks
+- DHCP on `10.0.1.0/24` subnet.
+- Tailscale on `100.64.0.0/10` subnet. FQDN: `skycam.mesh.vimium.net`.
+
+## Devices and connections
+- Camera Module 3 with wide-angle lens
+
diff --git a/hosts/skycam/default.nix b/hosts/skycam/default.nix
new file mode 100644
index 0000000..53e2c4c
--- /dev/null
+++ b/hosts/skycam/default.nix
@@ -0,0 +1,71 @@
+{ config, pkgs, ... }:
+
+{
+  imports = [
+    ./hardware-configuration.nix
+    ../server.nix
+  ];
+
+  hardware = {
+    raspberry-pi."4" = {
+      apply-overlays-dtmerge.enable = true;
+      audio.enable = false;
+      fkms-3d.enable = true;    # VideoCore with 512 MB CMA reservation
+      tc358743.enable = true;   # HDMI-to-CSI-2 converter
+      xhci.enable = false;
+    };
+    firmware = with pkgs; [
+      firmwareLinuxNonfree
+      wireless-regdb
+    ];
+  };
+
+  networking = {
+    hostId = "731d1660";
+    firewall = {
+      enable = true;
+      allowedTCPPorts = [ 8080 ];
+      allowedUDPPorts = [ 8080 ];
+    };
+  };
+
+  systemd.services.ustreamer = {
+    enable = true;
+    description = "uStreamer service";
+    unitConfig = {
+      Type = "simple";
+    };
+    serviceConfig = {
+      ExecStartPre = ''${pkgs.v4l-utils}/bin/v4l2-ctl \
+        --device=/dev/video0 \
+        --fix-edid-checksums \
+        --info-edid
+      '';
+      ExecStart = ''${pkgs.unstable.ustreamer}/bin/ustreamer \
+        --device=/dev/video0 \
+        --resolution=1280x720 \
+        --format=uyvy \
+        --encoder=m2m-image \
+        --workers=3 \
+        --persistent \
+        --dv-timings \
+        --drop-same-frames=30 \
+        --host=0.0.0.0 \
+        --port=8080
+      '';
+    };
+    wantedBy = [ "network-online.target" ];
+    confinement.mode = "chroot-only";
+  };
+
+  environment.systemPackages = with pkgs; [
+    git
+    neovim
+    libraspberrypi
+    raspberrypi-eeprom
+    v4l-utils
+    unstable.ustreamer
+  ];
+
+  system.stateVersion = "24.05";
+}
diff --git a/hosts/skycam/hardware-configuration.nix b/hosts/skycam/hardware-configuration.nix
new file mode 100644
index 0000000..b11d39c
--- /dev/null
+++ b/hosts/skycam/hardware-configuration.nix
@@ -0,0 +1,33 @@
+{ config, lib, modulesPath, ... }:
+
+{
+  imports = [
+    (modulesPath + "/installer/sd-card/sd-image-aarch64.nix")
+  ];
+
+  boot = {
+    kernelModules = [ "bcm2835-v4l2" ];
+    loader.raspberryPi.firmwareConfig = ''
+      start_x=1
+      gpu_mem=256
+    '';
+    supportedFilesystems = lib.mkForce [ "f2fs" "vfat xfs" ];
+    tmp.cleanOnBoot = true;
+  };
+
+  nixpkgs.overlays = [
+    (final: super: {
+      makeModulesClosure = x:
+        super.makeModulesClosure (x // { allowMissing = true; });
+    })
+  ];
+
+  fileSystems = {
+    "/" = {
+      device = "/dev/disk/by-label/NIXOS_SD";
+      fsType = "ext4";
+      options = [ "noatime" ];
+    };
+  };
+}
+