Changes to rpi setup

hosts/pi-main/hardware.nix

@@ -2,56 +2,37 @@
 
 # Hardware configuration for the primary Raspberry Pi 4 (8 GB).
 #
-# SD card layout assumed:
-#   /dev/mmcblk0p1  — /boot/firmware  (FAT32, ~256 MB)
-#   /dev/mmcblk0p2  — /              (ext4)
+# nixos-raspberrypi's raspberry-pi-4.base module (imported in flake.nix)
+# provides everything that nixos-hardware.raspberry-pi-4 previously did:
+#   - linuxPackages_rpi4 vendor kernel + matching firmware
+#   - u-boot bootloader with /boot/firmware partition management
+#   - initrd modules (xhci_pci, usbhid, usb_storage, vc4, pcie_brcmstb, etc.)
+#   - config.txt generation
+#
+# This file adds only host-specific overrides on top of that.
 #
 # External HD:
 #   Set homey.storage.device to the by-id path of your USB drive.
-#   Example: /dev/disk/by-id/usb-WD_Elements_12345-0:0-part1
 #   Find it with: ls -la /dev/disk/by-id/
 #
-# To generate this file fresh after installing NixOS on the Pi, run:
-#   nixos-generate-config --show-hardware-config
-# and merge the output here.
+# TODO: Verify SD card partition labels after first flash.
+#   The config assumes labels NIXOS_SD (root) and FIRMWARE (boot).
+#   Check with: lsblk -o NAME,LABEL
+#   Update fileSystems entries below if they differ.
 
 {
-  imports = [
-    (modulesPath + "/installer/scan/not-detected.nix")
-  ];
+  # tmpfs for /tmp — keep the SD card writes down
+  boot.tmp.useTmpfs = true;
 
-  # -------------------------------------------------------------------------
-  # Boot loader — Raspberry Pi 4 uses U-Boot / extlinux
-  # -------------------------------------------------------------------------
-  boot = {
-    loader = {
-      grub.enable          = false;
-      generic-extlinux-compatible.enable = true;
-    };
-
-    # Pi 4 kernel — use the mainline kernel with RPi patches
-    kernelPackages = pkgs.linuxPackages_rpi4;
-
-    # tmpfs for /tmp — keep the SD card writes down
-    tmp.useTmpfs = true;
-
-    # Modules needed for USB storage (external HD)
-    initrd.availableKernelModules = [ "xhci_pci" "usbhid" "usb_storage" "uas" ];
-    kernelModules = [];
-    extraModulePackages = [];
-  };
-
-  # -------------------------------------------------------------------------
   # Filesystems
-  # -------------------------------------------------------------------------
   fileSystems."/" = {
-    device  = "/dev/disk/by-label/NIXOS_SD";  # label the root partition NIXOS_SD when flashing
+    device  = "/dev/disk/by-label/NIXOS_SD";
     fsType  = "ext4";
     options = [ "noatime" ];
   };
 
   fileSystems."/boot/firmware" = {
-    device  = "/dev/disk/by-label/FIRMWARE";  # FAT32 boot partition
+    device  = "/dev/disk/by-label/FIRMWARE";
     fsType  = "vfat";
     options = [ "fmask=0022" "dmask=0022" ];
   };
@@ -61,24 +42,9 @@
 
   swapDevices = [];
 
-  # -------------------------------------------------------------------------
-  # Hardware
-  # -------------------------------------------------------------------------
-  hardware = {
-    # Enable the RPi firmware (needed for GPU, WiFi, Bluetooth)
-    raspberry-pi."4".apply-overlays-dtmerge.enable = true;
-
-    # Disable GPU memory split for a headless server (gives more RAM to OS)
-    # Set via config.txt if needed: gpu_mem=16
-  };
-
-  # -------------------------------------------------------------------------
   # Platform
-  # -------------------------------------------------------------------------
   nixpkgs.hostPlatform = lib.mkDefault "aarch64-linux";
 
-  # -------------------------------------------------------------------------
   # Power management
-  # -------------------------------------------------------------------------
   powerManagement.cpuFreqGovernor = lib.mkDefault "ondemand";
 }