Revert "Update rpi base"

This reverts commit 5903eb650a.

hosts/skycam/default.nix

@@ -6,11 +6,49 @@
     ../server.nix
   ];
 
-  raspberry-pi-nix = {
-    board = "bcm2711";
-    libcamera-overlay.enable = false;
+  hardware = {
+    raspberry-pi."4" = {
+      apply-overlays-dtmerge.enable = true;
+      audio.enable = false;
+      xhci.enable = false;
+    };
+    deviceTree = {
+      enable = true;
+      filter = "*rpi-4-*.dtb";
+      # From https://github.com/Electrostasy/dots/blob/3b81723feece67610a252ce754912f6769f0cd34/hosts/phobos/klipper.nix#L43-L65
+      overlays =
+        let
+          mkCompatibleDtsFile = dtbo:
+            let
+              drv = pkgs.runCommand "fix-dts" { nativeBuildInputs = with pkgs; [ dtc gnused ]; } ''
+                mkdir "$out"
+                dtc -I dtb -O dts ${dtbo} | sed -e 's/bcm2835/bcm2711/' > $out/overlay.dts
+              '';
+            in
+              "${drv}/overlay.dts";
+
+          inherit (config.boot.kernelPackages) kernel;
+        in
+          [
+            {
+              name = "imx708.dtbo";
+              dtsFile = mkCompatibleDtsFile "${kernel}/dtbs/overlays/imx708.dtbo";
+            }
+            {
+              name = "vc4-kms-v3d-pi4.dtbo";
+              dtsFile = mkCompatibleDtsFile "${kernel}/dtbs/overlays/vc4-kms-v3d-pi4.dtbo";
+            }
+          ];
+    };
+    firmware = with pkgs; [
+      firmwareLinuxNonfree
+    ];
   };
 
+  services.udev.extraRules = ''
+    SUBSYSTEM="dma_heap", GROUP="video", MODE="0600"
+  '';
+
   networking = {
     hostId = "731d1660";
     firewall = {